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Occurrence and Pathways of Manure-borne 17beta-Estradiol in Vadose Zone Water
Technology Transfer Automated Retrieval System (TEKTRAN)
Reproductive hormones, such as 17beta-estradiol (E2), can cause physiological and reproductive disorders in numerous species at low part per trillion concentrations. The persistence and transport pathways of manure-borne E2 in agricultural soils were determined by comparing the occurrence of E2 in t...
Technology Transfer Automated Retrieval System (TEKTRAN)
Hormones, such as 17beta-estradiol (E2), have the potential of causing widespread physiological and reproductive disorders in numerous species due to their potency and presence in the environment. The occurrence of E2 in the unsaturated zone (0.60 m depth) was determined with wick lysimeters and com...
[Levels of testosterone and 17-beta estradiol in the seminal plasma of bulls and boars].
Kozumplík, J; Vinkler, A
The levels of testosterone (T) and 17-beta-estradiol (E2) in seminal plasma were determined by the direct RIA method with tritium-labelled testosterone and 17-beta-estradiol. Testosterone was determined in 47 ejaculates and E2 in 132 ejaculates of seven bulls whose age ranged from 10 to 26 months, and in 60 ejaculates of two breeding boars old 20 months. The seminal plasma of bulls was found to contain 2.09 +/- 1.67 nmol/l testosterone and 2.75 +/- 1.94 nmol/l E2. Without respect to the age of the sires, the marginal values of the studied steroids showed a comparatively high fluctuation so that the average values are not very different between individual animals. No relation was found between the level of steroids and the concentration of fructose; this applies to the fertile bulls as well as to the bull suffering from epididymitis with the formation of epididymal cysts. Breeding boars had 0.338 nmol/ E2 (+/- 0.3) and 6.40 +/- 4.01 nmol/l testosterone in their seminal plasma. When the obtained values are recalculated to an average ejaculate volume, 5 ml of the seminal plasma of bulls will contain about 0.013 nmol E2 and 0.010 nmol T and 300 ml of the seminal plasma of boars will contain about 0.101 nmol E2 and 1.920 nmol T. PMID:6818748
2-Hydroxy-4-glutathion-S-yl-17beta-estradiol and 2-hydroxy-1-glutathion-S-yl-17beta-estradiol produce oxidative stress and renal toxicity in an animal model of 17beta-estradiol-mediated nephrocarcinogenicity.
Butterworth, M; Lau, S S; Monks, T J
Chronic exposure of male Syrian hamsters to a variety of estrogens has been linked with a high incidence of renal carcinoma. The basis of this species and tissue specificity remains to be resolved. We have recently shown that (i) 17beta-estradiol is nephrotoxic in the hamster in a manner dependent upon the activity of gamma-glutamyl transpeptidase and (ii) 17beta-estradiol is metabolized to a variety of catechol estrogen glutathione conjugates (Butterworth et al., Carcinogenesis, 18, 561-567, 1997). We report that the catechol estrogen glutathione conjugates exhibit redox properties similar to those of the catechol estrogens, and maintain the ability to generate superoxide radicals. Administration of 2-hydroxy-4-glutathion-S-yl-17beta-estradiol or 2-hydroxy-1-glutathion-S-yl-17beta-estradiol (0.27-5.0 micromol/kg) to Syrian hamsters, produces mild nephrotoxicity. Repeated daily administration of 2-hydroxy-4-glutathion-S-yl-17beta-estradiol causes a sustained elevation in urinary markers of renal damage and in the concentration of renal protein carbonyls and lipid hydroperoxides. Catechol estrogen oxidation and conjugation of glutathione in the liver, followed by the selective uptake of the redox active conjugates in tissues rich in gamma-glutamyl transpeptidase may contribute to 17beta-estradiol-induced renal tumors in the hamster. PMID:9472704
Modeling of Coupled Degradation, Sorption, and Transport of 17beta-Estradiol in Undisturbed Soil
Technology Transfer Automated Retrieval System (TEKTRAN)
The presence of 17 beta-estradiol in the environment, even at part-per trillion concentrations, may raise significant concern regarding the health of aquatic organisms. Once 17 beta-estradiol is released into the environment from human and animal sources, its fate and transport is controlled by fact...
Bioequivalence of a newly developed 17 beta-estradiol tablet versus an identical reference formulation
Gisclon; Bowen; O'Reilly; Lakewold; Curtin; Larson; Palmer; Natarajan; Wong
Two open-label, randomized studies determined the bioequivalence of a test preparation (Prefest) of micronized 17 beta-estradiol (E2, CAS 50-28-2) tablets as compared with a reference preparation of micronized E2 tablets in healthy postmenopausal women. In Study 1, 36 fasting subjects received 4 test preparation 0.5-mg E2 tablets in one period and 4 reference preparation 0.5-mg E2 tablets in the other period. In Study 2, 36 fasting subjects received 1 test preparation 2-mg E2 tablet in one period and 1 reference preparation 2-mg E2 tablet in the other period. Blood samples were collected before and after dosing to determine serum concentrations of E2, estrone, and estrone sulfate. The 90% confidence intervals for the ratios of mean Cmax and AUC values (test preparation/reference preparation) for all three analytes were within the prescribed 80%-125% range of bioequivalence. In conclusion, the test preparation 0.5-mg and 2-mg micronized E2 tablets are bioequivalent to the respective strength reference preparation micronized E2 tablets. PMID:11105233
17beta-estradiol protects male mice from cuprizone-induced demyelination and oligodendrocyte loss.
Taylor, Lorelei C; Puranam, Kasturi; Gilmore, Wendy; Ting, Jenny P-Y; Matsushima, Glenn K
In addition to regulating reproductive functions in the brain and periphery, estrogen has tropic and neuroprotective functions in the central nervous system (CNS). Estrogen administration has been demonstrated to provide protection in several animal models of CNS disorders, including stroke, brain injury, epilepsy, Parkinson's disease, Alzheimer's disease, age-related cognitive decline and multiple sclerosis. Here, we use a model of toxin-induced oligodendrocyte death which results in demyelination, reactive gliosis, recruitment of oligodendrocyte precursor cells and subsequent remyelination to study the potential benefit of 17beta-estradiol (E2) administration in male mice. The results indicate that E2 partially ameliorates loss of oligodendrocytes and demyelination in the corpus callosum. This protection is accompanied by a delay in microglia accumulation as well as reduced mRNA expression of the pro-inflammatory cytokine, tumor necrosis factor alpha (TNFalpha), and insulin-like growth factor-1 (IGF-1). E2 did not significantly alter the accumulation of astrocytes or oligodendrocyte precursor cells, or remyelination. These data obtained from a toxin-induced, T cell-independent model using male mice provide an expanded view of the beneficial effects of estrogen on oligodendrocyte and myelin preservation. PMID:20347981
17 beta-estradiol hydroxylation catalyzed by human cytochrome P450 1B1.
Hayes, C L; Spink, D C; Spink, B C; Cao, J Q; Walker, N J; Sutter, T R
The 4-hydroxy metabolite of 17 beta-estradiol (E2) has been implicated in the carcinogenicity of this hormone. Previous studies showed that aryl hydrocarbon-receptor agonists induced a cytochrome P450 that catalyzed the 4-hydroxylation of E2. This activity was associated with human P450 1B1. To determine the relationship of the human P450 1B1 gene product and E2 4-hydroxylation, the protein was expressed in Saccharomyces cerevisiae. Microsomes from the transformed yeast catalyzed the 4- and 2-hydroxylation of E2 with Km values of 0.71 and 0.78 microM and turnover numbers of 1.39 and 0.27 nmol product min-1.nmol P450-1, respectively. Treatment of MCF-7 human breast cancer cells with the aryl hydrocarbon-receptor ligand indolo[3,2-b]carbazole resulted in a concentration-dependent increase in P450 1B1 and P450 1A1 mRNA levels, and caused increased rates of 2-, 4-, 6 alpha-, and 15 alpha-hydroxylation of E2. At an E2 concentration of 10 nM, the increased rates of 2- and 4-hydroxylation were approximately equal, emphasizing the significance of the low Km P450 1B1-component of E2 metabolism. These studies demonstrate that human P450 1B1 is a catalytically efficient E2 4-hydroxylase that is likely to participate in endocrine regulation and the toxicity of estrogens. Images Fig. 1 PMID:8790407
17 beta-estradiol hydroxylation catalyzed by human cytochrome P450 1B1.
Hayes, C L; Spink, D C; Spink, B C; Cao, J Q; Walker, N J; Sutter, T R
The 4-hydroxy metabolite of 17 beta-estradiol (E2) has been implicated in the carcinogenicity of this hormone. Previous studies showed that aryl hydrocarbon-receptor agonists induced a cytochrome P450 that catalyzed the 4-hydroxylation of E2. This activity was associated with human P450 1B1. To determine the relationship of the human P450 1B1 gene product and E2 4-hydroxylation, the protein was expressed in Saccharomyces cerevisiae. Microsomes from the transformed yeast catalyzed the 4- and 2-hydroxylation of E2 with Km values of 0.71 and 0.78 microM and turnover numbers of 1.39 and 0.27 nmol product min-1.nmol P450-1, respectively. Treatment of MCF-7 human breast cancer cells with the aryl hydrocarbon-receptor ligand indolo[3,2-b]carbazole resulted in a concentration-dependent increase in P450 1B1 and P450 1A1 mRNA levels, and caused increased rates of 2-, 4-, 6 alpha-, and 15 alpha-hydroxylation of E2. At an E2 concentration of 10 nM, the increased rates of 2- and 4-hydroxylation were approximately equal, emphasizing the significance of the low Km P450 1B1-component of E2 metabolism. These studies demonstrate that human P450 1B1 is a catalytically efficient E2 4-hydroxylase that is likely to participate in endocrine regulation and the toxicity of estrogens. PMID:8790407
Effects of 17 beta-estradiol on serum hormone concentrations and estrous cycle in female Crl:CD BR rats: effects on parental and first generation rats.
Biegel, L B; Cook, J C; Hurtt, M E; O'Connor, J C
The recently passed Food Quality Protection Act of 1996 requires the U.S. EPA to implement screening strategies for endocrine active compounds (EACs) within the next 2 years. Interpreting results from screening tests is complicated by the absence of traditional dietary rodent bioassay data with model estrogenic compounds such as 17 beta-estradiol. Thus, a 90-day/one-generation reproduction study with 17 beta-estradiol was designed to: (1) provide such baseline data; (2) set dose levels for multigeneration reproduction and combined chronic toxicity/oncogenicity studies; and (3) evaluate various mechanistic/biochemical endpoints for inclusion in these follow-up studies. The current article describes the effects of dietary administration of 0, 0.05, 2.5, 10, and 50 ppm 17 beta-estradiol on the serum hormone concentrations and estrous cyclicity of female Crl:CD BR rats and evaluates a sampling strategy for measuring serum hormone levels in cycling female rats. Serum hormones were measured at three time points during a 90-day dietary exposure (1 week, 28 days, and 90 days) and in the F1 generation rats on postnatal day 98. Over the course of the 90-day feeding study for the P1 generation and from postnatal days 21 to 98 for the F1 generation, the estrous cycle was monitored daily in 10 rats/group. In P1 generation rats, dietary administration of 2.5, 10, and 50 ppm 17 beta-estradiol produced a dose-dependent increase in serum estradiol (E2) concentrations at all time points. In contrast, administration of 0.05, 2.5, 10, and 50 ppm 17 beta-estradiol produced a dose-dependent decrease in serum progesterone (P4) concentrations on test day 90, which correlated with an absence of corpora lutea and ovarian atrophy. At 10 and 50 ppm 17 beta-estradiol, serum luteinizing hormone (LH) concentrations were consistently decreased at all time points and were decreased at 2.5 ppm on test day 90. Serum prolactin (PRL) concentrations were increased at 50 ppm 17 beta-estradiol on test day 90. Serum follicle stimulating hormone (FSH) concentrations were either similar to the control levels or minimally changed at all time points. No F1 generation rats were produced at 10 or 50 ppm 17 beta-estradiol. In F1 generation rats, serum E2 concentrations were increased and P4 concentrations were decreased at a dietary concentration of 2.5 ppm 17 beta-estradiol, while serum concentrations of LH, FSH, and PRL were similar to the control. Dietary administration of 17 beta-estradiol at concentrations of 2.5 (both generations) and 10 and 50 ppm (P1 generation only) produced marked effects on the estrous cycle: decreased number of cycles, increased mean cycle length, and decreased number of normally cycling rats. The estrous cyclicity of rats fed 2.5 ppm 17 beta-estradiol appeared more severely affected in rats of the F1 generation than in rats of the P1 generation. Whether this increase in severity is related to an in utero exposure and/or greater mean daily intake of 17 beta-estradiol in the F1 generation rats in the postnatal period is unclear. Another goal of this study was to evaluate whether a single time point sampling strategy using cycling female rats could be used to detect compound-related changes in serum hormone concentrations. In evaluating a sampling strategy for measuring serum hormone levels, it appears that detection of compound-related alterations in serum hormone concentrations can be best detected by sampling during diestrus. Since the stage of the cycle dramatically influences hormone concentrations, large sample sizes (n = 50) are needed if serum hormone measurements are not matched with the stage of the cycle. The data indicate that this strategy of measuring serum hormone concentrations has utility in detecting compound-related effects within the confines of a traditional guideline study (subchronic, chronic, or multigenerational reproduction study). PMID:9742653
Effects of 17 beta-estradiol, progesterone and tamoxifen on in vitro proliferation of human pituitary adenomas: correlation with specific cellular receptors.
Caronti, B; Palladini, G; Bevilacqua, M G; Petrangeli, E; Fraioli, B; Cantore, G; Tamburrano, G; Carapella, C M; Jaffrain-Rea, M L
Six human pituitary adenoma cultures, characterized for estrogen and progesterone (Pg) receptors, were treated with 17 beta-estradiol (17 beta-E2), Pg and tamoxifen (TAM) at different concentrations, alone and in combination, for 2, 4 and 8 days. Cell proliferation data showed in most cases a stimulating effect of 17 beta-E2 and an inhibitory effect of Pg on cell growth, which appeared to be correlated with specific receptor expression, but independent of pituitary cell hormone content. A marked inhibitory effect of TAM on cell proliferation was present in all cases, but, on the contrary, was independent of estrogen receptor expression. PMID:8493452
Acute effects of 17beta -estradiol on femoral veins from adult gonadally intact and ovariectomized female pigs.
Bracamonte, M P; Jayachandran, M; Rud, K S; Miller, V M
Our experiments were designed to determine the acute effects of 17beta-estradiol on femoral veins from intact and ovariectomized female pigs. Rings of femoral veins with or without endothelium were suspended in organ chambers for measurement of isometric force. Concentration-response curves to 17beta-estradiol (10(-9) to 10(-5) M) were obtained in veins contracted with prostaglandin F(2alpha) in the absence and presence of inhibitors of either estrogen receptors (ICI-182780; 10(-5) M), nitric oxide synthase [N(G)-monomethyl-l-arginine (l-NMMA); 10(-4) M], soluble guanylate cyclase (1-H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one; 10(-5) M), or potassium channels (tetraethylammonium; 10(-2) M). Estrogen receptors were identified with the use of Western blotting and immunostaining in veins of both groups. 17beta-Estradiol caused acute endothelium-dependent relaxations in both groups. Relaxations to 17beta-estradiol were inhibited by l-NMMA and 1-H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one but not ICI-182780. Tetraethylammonium inhibited relaxations only in veins with endothelium from intact females. Results indicate that 17beta-estradiol causes acute endothelium-dependent relaxations in femoral veins. The relative contribution of nitric oxide and K(+) channels as mechanisms involved in relaxations to 17beta-estradiol in femoral veins is modulated by ovarian status. PMID:12388282
Stimulation of growth and changes in the hepatic transcriptome by 17beta-estradiol in the yellow perch (Perca flavescens).
Goetz, Frederick W; Rise, Matthew L; Rise, Marlies; Goetz, Giles W; Binkowski, Frederick; Shepherd, Brian S
The effects of dietary 17beta-estradiol (E(2)) on growth and liver transcriptomics were investigated in the yellow perch (Perca flavescens). After a 3-mo treatment, E(2) significantly stimulated an increase in length and weight of juvenile male and female perch relative to control animals. The increase was significantly greater in females compared with males. Separate, unnormalized cDNA libraries were constructed from equal quantities of RNA from 6 male and 6 female livers of E(2)-treated and control perch, and 3,546 and 3,719 expressed sequence tags (ESTs) were obtained, respectively. To characterize E(2)-regulated transcripts, EST frequencies between libraries were calculated within contiguous sequences that were assembled from the combined ESTs of both libraries. Frequencies were also determined in EST transcript groupings produced by aligning all of the ESTs from both libraries at the nucleotide level. From these analyses, there were 28 annotated transcripts that were regulated by 75% between libraries and for which there were at least 5 ESTs of the same transcript between libraries. Regulation of a subset (14) of these transcripts was confirmed by quantitative reverse transcription-polymerase chain reaction (QPCR). Transcripts that were upregulated by E(2) included reproduction-related proteins, binding proteins, and proteases and protease inhibitors. While not part of the transcript frequency analysis, QPCR showed significant upregulation of estrogen receptor esr1 and of insulin-like growth factor I (IGF-I) in E(2) livers. E(2)-downregulated transcripts represented a variety of functional categories including components of the respiratory chain, lipid transport and metabolism, glycolysis, amino acid and nitrogen metabolism, binding proteins, a hydrolytic enzyme, and a transcriptional regulator. In perch it appears that exogenous estrogen drastically shifts liver metabolism toward the production of lipoproteins and carbohydrate binding proteins, and that the growth-promoting action may involve an increase in hepatic IGF-I production. PMID:19549814
17beta-estradiol is protective in spinal cord injury in post- and pre-menopausal rats.
Chaovipoch, Pimonporn; Jelks, Karen A Bozak; Gerhold, Lynnette M; West, Eric J; Chongthammakun, Sukumal; Floyd, Candace L
The neuroprotective effects of 17 beta -estradiol have been shown in models of central nervous system injury, including ischemia, brain injury, and more recently, spinal cord injury (SCI). Recent epidemiological trends suggest that SCIs in elderly women are increasing; however, the effects of menopause on estrogen-mediated neuroprotection are poorly understood. The objective of this study was to evaluate the effects of 17beta-estradiol and reproductive aging on motor function, neuronal death, and white matter sparing after SCI of post- and pre-menopausal rats. Two-month-old or 1- year-old female rats were ovariectomized and implanted with a silastic capsule containing 180 microg/mL of 17beta-estradiol or vehicle. Complete crush SCI at T8-9 was performed 1 week later. Additional animals of each age group were left ovary-intact but were spinal cord injured. The Basso, Beattie, Bresnahan (BBB) locomotor test was performed. Spinal cords were collected on post-SCI days 1, 7, and 21, and processed for histological markers. Administration of 17beta-estradiol to ovariectomized rats improved recovery of hind-limb locomotion, increased white matter sparing, and decreased apoptosis in both the post- and pre-menopausal rats. Also, ovary-intact 1-year-old rats did worse than ovary-intact 2-month-old rats, suggesting that endogenous estrogen confers neuroprotection in young rats, which is lost in older animals. Taken together, these data suggest that estrogen is neuroprotective in SCI and that the loss of endogenous estrogen-mediated neuroprotective seen in older rats can be attenuated with exogenous administration of 17beta-estradiol. PMID:16774470
Enhancement of trypsin-induced contraction by in vivo treatment with 17beta-estradiol and progesterone in rat myometrium.
Aman, Murasaki; Hirano, Katsuya; Nishimura, Junji; Nakano, Hitoo; Kanaide, Hideo
We have previously reported that the contractile response to thrombin and trypsin was enhanced in the pregnant rat myometrium. We herein determined whether or not sex hormones contribute to this enhancement and the expression of protease-activated receptors (PARs). The nonpregnant rats received daily injections of either 17beta-estradiol or progesterone, and then the contractile response of the myometrium was examined ex vivo. Treatment with either 17beta-estradiol or progesterone had almost no significant enhancing effect on the high K(+)- or oxytocin-induced contraction. On the other hand, both 17beta-estradiol and progesterone dose-dependently enhanced the contractile response to trypsin. A maximal enhancement was obtained at 25 and 40 mg kg weight(-1) day(-1) for 17beta-estradiol and progesterone, respectively. The extent of the enhancement of the trypsin-induced contraction seen in the sex hormone-treated rats in the present study was comparable to that reported in the pregnant rats. However, the contractile response to thrombin and PAR1/PAR2-AP, SFLLRNP was not enhanced either by progesterone or 17beta-estradiol. PAR2-AP and PAR4-AP failed to induce contraction under any conditions. PAR1 mRNA was scarcely detected in the control myometrium by an RT-PCR analysis, while it slightly increased only in the progesterone-treated rats. Neither PAR2 nor PAR4 mRNA was detected. We thus conclude that the responsiveness to trypsin, but not thrombin, is controlled by sex hormones. A novel type of receptor, other than PAR1, PAR2 or PAR4, is suggested to mediate the trypsin-induced contraction as in the case of the pregnant rat myometrium. PMID:16056237
Fathead minnow vitellogenin: Complementary DNA sequence and messenger RNA and protein expression after 17{beta}-estradiol treatment
Korte, J.J.; Kahl, M.D.; Jensen, K.M.; Pasha, M.S.; Parks, L.G.; LeBlanc, G.A.; Ankley, G.T.
Induction of vitellogenin (VTG) in oviparous animals has been proposed as a sensitive indicator of environmental contaminants that activate the estrogen receptor. In the present study, a sensitive ribonuclease protection assay (RPA) for VTG messenger RNA (mRNA) was developed for the fathead minnow (Pimephales promelas), a species proposed for routine endocrine-disrupting chemical (EDC) screening. The utility of this method was compared with an enzyme-linked immunosorbent assay (ELISA) specific for fathead minnow VTG protein. Assessment of the two methods included kinetic characterization of the plasma VTG protein and hepatic VTG mRNA levels in male fathead minnows following intraperitoneal injections of 17{beta}-estradiol (E2) at two dose levels (0.5, 5.0 mg/kg). Initial plasma E2 concentrations were elevated in a dose-dependent manner but returned to normal levels within 2 d. Lover VTG mRNA was detected within 4 h, reached a maximum around 48 h, and returned to normal levels in about 6 d. Plasma VTG protein was detectable within 16 h of treatment reached maximum levels at about 72 h. and remained near these maximum levels for at least 18 d. While the RPA was about 1,000 times more sensitive than the ELISA, the ELISA appears superior for routine screening tests. The ELISA method is relatively simple to perform and, because males lack a clearance mechanism for VTG, the protein remains at relatively high concentrations in the plasma for an extended period of time. As part of the development of the RPA, the complementary DNA (cDNA) sequence for fathead minnow VTG was determined and the deduced amino acid sequence compared with VTG sequences for other fish species.
Local Delivery of 17-Beta-Estradiol Modulates Collagen Content in Coronary Porcine Arteries after PTCA and Stent Implantation
Pedro Geraldes; Pascale Geoffroy; Isabelle Cloutier; Martin G. Sirois; Jean-François Tanguay
Background: Percutaneous transluminal coronary angioplasty (PTCA) and stent implantation are associated with intimal hyperplasia and extracellular matrix (ECM) accumulation, resulting in restenosis. We showed that local delivery of 17-beta-estradiol (17?E) reduced restenosis following PTCA and stent implantation by 47 and 23%, respectively. Because estrogens decreased type I and type III collagen synthesis in vitro, we hypothesized that local delivery of
Rapid vascular escape of arterially injected 16alpha-radioiodo, 17beta-estradiol
Scharl, A.; Holt, J.A. (Univ. of Chicago, IL (United States))
The authors undertook this study because confirmation of a rapid vascular escape and slow release back into the circulatory system suggests that arterial injection of radiohalogenated steroid receptor ligands might provide an efficacious route of administration for imaging or treatment of receptor-rich malignant tumors in peripheral tissues. The authors injected radiolabeled 16alpha-iodo, 17beta-estradiol ([I]-E) into the femoral artery of swine in a solution that contained [[sup 125]I]-E in a known ratio to [[sup 99]Tc]-labeled red blood cells. Fractions of femoral venous blood were collected at short intervals during 10 min. They looked for changes in the ratio of the radiolabeles. [[sup 99m]Tc]-labeled red blood cells are known to remain in the vascular system for an hour or more. After passage of the injectate through the capillary bed of the swine leg, a dramatic decrease of the initial [sup 125]I:[sup 99m]Tc ratio to only 10% was observed in the femoral venous blood. This ratio increased gradually during the next 10 min to approximately 30% of that in the injectate, indicating that a significant portion (approximately 90%) of the [[sup 125]I]-E was initially trapped in the limb and then slowly re-entered the vascular system. To obtain visual confirmation of the rapid vascular escape of iodo-estrogen, they injected either an imageable form of [I]-E ([[sup 123]I]-E) or [[sup 99m]Tc]-labeled red blood cells into the dorsal aorta of superovulated rabbits, whose smaller size allowed whole-body imaging. The biodistributions of these radiopharmaceuticals were surveyed continuously by real-time planar gamma imaging. A large fraction of [I]-E escapes from the vascular system during the first pass through an organ or limb, without regard to the estrogen receptor content of the tissue. 28 refs., 3 figs., 1 tab.
Degradation of 17beta-estradiol in aqueous solution by ozonation in the presence of manganese(II) and oxalic acid.
Jiang, Liying; Zhang, Lu; Chen, Jianmeng; Ji, Hong
Natural estrogens, such as 17beta-estradiol (E2), are the main substances responsible for estrogenic activity found in domestic sewage. In the work described herein, the degradation of E2 has been investigated by single ozonation and catalytic ozonation in the presence of manganese ion (Mn2+) and oxalic acid. The presence of Mn2+ and oxalic acid in the ozonation processes significantly improved the E2 degradation and, hence, the reduction of estrogenic activity in aqueous solution. The addition of Mn2+ and oxalic acid produced many more hydroxyl radicals in the catalytic ozonation system than in the single ozonation system. Oxidation products formed during ozonation of E2 have been identified by means of gas chromatography-mass spectrometry (GC-MS), on the basis of which a possible reaction pathway for E2 degradation by ozonation is proposed. E2 was first oxidized to hydroxyl-semiquinone isomers, and these were subsequently degraded to low molecular weight compounds such as oxalic acid and malonic acid. The latter were easily oxidized by ozone to form carbon dioxide (CO2). The results demonstrate that the ozonation-Mn(2+)-oxalic acid system may serve as a powerful tool for removing E2, and the addition of Mn2+ and oxalic acid is favourable for the complete removal of estrogenic activity induced by steroid estrogens in aqueous solution. PMID:23530323
Differential effects of 17beta-estradiol, conjugated equine estrogen, and raloxifene on mRNA expression, aggregation, and secretion in platelets.
Jayachandran, Muthuvel; Mukherjee, Rajarshi; Steinkamp, Thomas; LaBreche, Peter; Bracamonte, Margarita P; Okano, Hiroya; Owen, Whyte G; Miller, Virginia M
Changes in platelet functions could contribute to thrombotic risk associated with estrogen treatments. This study was designed to test the hypothesis that three clinically relevant estrogenic treatments affect platelet function comparably. Adult female pigs were ovariectomized and randomized to either no treatment or treatment with oral 17 beta-estradiol (2 mg/day), conjugated equine estrogen (0.625 mg/day), or raloxifene (60 mg/day) for 4 wk. Platelet turnover, aggregation, and secretion were assessed before and after treatment. Platelet turnover and mRNA increased significantly only in pigs treated with 17 beta-estradiol. Expression of estrogen receptors increased with ovariectomy and decreased with all treatments. Platelet aggregation and secretion of ATP, platelet-derived growth factor, and matrix metalloproteinase-2 increased with ovariectomy. All treatments reduced both aggregation and secretion. Expression of mRNA for constitutive endothelial nitric oxide synthase (eNOS), but not eNOS protein, increased with ovariectomy. Only eNOS mRNA decreased with all treatments, but only treatment with 17 beta-estradiol increased secretion of nitric oxide from intact platelets. Platelets from 17 beta-estradiol-treated animals caused relaxation of coronary arteries, which was sensitive to inhibition of nitric oxide. Although three different estrogenic treatments reversed increases in platelet aggregation caused by ovariectomy, only 17 beta-estradiol increased platelet RNA and release of platelet-derived nitric oxide. These differences reflect transcriptional and posttranscriptional regulation of protein synthesis in bone marrow megakaryocytes and circulating platelets. PMID:15653758
Gamma irradiation for terminal sterilization of 17beta-estradiol loaded poly-(D,L-lactide-co-glycolide) microparticles.
Mohr, D; Wolff, M; Kissel, T
17beta-Estradiol-loaded microparticles using poly-(D, L-lactide-co-glycolide) polymer (PLG) were prepared by a modified spray-drying method and the effects of gamma-irradiation on drug substance, polymer and microparticles were investigated. Irradiation doses ranging from 5.1 to 26.6 kGy were applied using a 60Co-radiation source. 17beta-Estradiol drug substance showed excellent stability against gamma-irradiation in the investigated dose range, whereas microencapsulated estradiol seems to be converted to conjugation products with PLG, and to a lesser extent to the degradation product 9,11-dehydroestradiol. The weight-average molecular weight of the PLG polymers decreased with increasing irradiation dose while polydispersity indices (M(w)/M(n)) remained nearly unchanged, compatible with a random chain scission mechanism in lactide/glycolide-copolymer degradation. In vitro drug release studies showed accelerated kinetics with increasing irradiation doses due to dose dependent polymer degradation. Microbiological process monitoring showed decreasing bioburden with increasing spraying time, which was successfully further reduced by applying irradiation sterilization. Microencapsulated test spore suspensions of Bacillus pumilus ATCC 27142, the official test specimen for the gamma-sterilization process, revealed effective reduction of bioburden, confirming its published D(10) value. In conclusion, our studies demonstrated efficacy of gamma-irradiation as terminal sterilization method for poly-(D,L-lactide-co-glycolide) polymer-based drug delivery systems. The sterilization conditions need to be carefully adjusted for the final dosage form. PMID:10469916
Human chorionic gonadotropin (hCG) prevents the transformed phenotypes induced by 17 beta-estradiol in human breast epithelial cells.
Kocdor, Hilal; Kocdor, Mehmet A; Russo, Jose; Snider, Kara E; Vanegas, Johana E; Russo, Irma H; Fernandez, Sandra V
Human chorionic gonadotropin (hCG), a hormone produced during pregnancy, can elicit life-long refractoriness to carcinogenesis by differentiation of the breast epithelium. Human breast epithelial cells MCF-10F form tubules in collagen, mimicking the normal ductules. We have shown that 17 beta-estradiol (E2) alter the ductulogenic pattern of these cells. The effect of the recombinant hCG (rhCG) in vitro was evaluated on the transformation of MCF-10F induced by E2. MCF-10F cells were treated with 70 nM E2 alone or in combination with 50 IU/ml rhCG during 2 weeks, while the controls were treated with DMSO (the solvent in which E2 was dissolved) or rhCG alone. At the end of treatment, the cells were plated in type I collagen matrix (3D-cultures) for detecting 2 main phenotypes of cell transformation, namely the loss of ductulogenic capacity and the formation of solid masses. Although E2 significantly increased solid mass formation, this effect was prevented when MCF-10F cells were treated with E2 in combination with rhCG. Furthermore, E2 increased the main duct width (p < 0.001), and caused a disruption of the luminal architecture, whereas rhCG increased the length of the tubules (p < 0.001) and produced tertiary branching. In conclusion, rhCG was able to abrogate the transforming abilities of estradiol, and had the differentiating property by increasing the branching of the tubules formed by breast epithelial cells in collagen. These results further support our hypothesis, known as the terminal differentiation hypothesis of breast cancer prevention, that predicts that hCG treatment results in protection from tumorigenic changes by the loss of susceptible stem cells 1 through a differentiation to refractory stem cells 2 and increase differentiation of the mammary gland. PMID:19647089
Treatment with raloxifene and 17beta-estradiol differentially modulates nitric oxide and prostanoids in venous endothelium and platelets of ovariectomized pigs.
Lewis, Debra A; Avsar, Murat; Labreche, Peter; Bracamonte, Margarita; Jayachandran, Muthuvel; Miller, Virginia M
Oral treatment with raloxifene, a synthetic estrogen receptor modulator (SERM), or 17beta-estradiol (E2) increases risk for venous thrombosis in women. Acute application of either substance releases endothelium-derived factors from isolated femoral veins but it is not known how their chronic use affects venous functions or the interaction of platelets with veins. This study tested the hypothesis that treatment of ovariectomized animals with oral raloxifene or E2 would increase release of proaggregatory factors from venous endothelium and platelets. Ovariectomized (OVX) pigs were either untreated or treated with oral raloxifene (60 mg/day) or E2 (2 mg/day) for 4 weeks. Plasma concentrations of nitric oxide were comparable in both treatment groups and greater than in OVX pigs. Ratio of plasma thromboxane to prostacyclin was twofold greater in raloxifene compared to E2-treated pigs. In isolated femoral veins, NG-monomethyl-L-arginine (L-NMMA; 10(-4) M) augmented endothelium-dependent relaxations to adenosine diphosphate in veins from E2-treated pigs but inhibited relaxations in veins from raloxifene-treated pigs. Addition of indomethacin (10(-5) M) reversed these effects. Endothelium-dependent relaxations to thrombin were inhibited by L-NMMA only in OVX and raloxifene-treated pigs. Autologous platelets contracted veins in all groups; the magnitude of contractions depended upon the number of platelets and existing tone. Basal release of thromboxane from platelets was greatest in raloxifene compared to OVX or E2-treated pigs. Raloxifene treatment compared to E2 increased production of contractile and proaggregatory prostanoids from venous endothelium and platelets. These differences, if found in humans, may contribute to varying degrees of thrombotic risk with the SERM compared to the natural hormone. PMID:17110805
Modulation of 17{beta}-estradiol-induced responses in fish by cytochrome P4501A1 inducing compounds
Anderson, M.J.; Hinton, D.E. [Univ. of California, Davis, CA (United States)
Some compounds which induce cytochrome P4501A1 (CYP1A1) are antiestrogenic in mammalian bioassay, and this effect is linked to aryl hydrocarbon (Ah) receptor. Liver of fish synthesizes estrogen-inducible egg yolk precursor protein vitellogenin (Vg) which is critical for oocyte maturation and ovarian development. To determine if Ah receptor-linked endocrine modulation could occur in fish liver, primary cultures of juvenile rainbow trout (Oncorhynchus mykiss) liver cells were co-administered 17{beta}-estradiol and CYP1A1 inducing compounds. Vitellogenin and albumin, estimated by ELISA measurement of concentration in the media 48 hrs after treatment, formed the basis for the test. Cellular CYP1A1 protein content and catalytic activity was estimated by ELISA and ethoxyresorufin-O-deethylase (EROD) activity assays respectively. Equivalent viability (mitochondrial dehydrogenase activity) and secretary functional capacity (albumin synthesis) were estimated and correlated with other results. In descending order, 2,3,4,7,8 pentachlorodibenzofuran (10{sup {minus}12} to 10{sup {minus}8} M) > 2,3,7,8 tetrachlorodibenzo-p-dioxin {approx_equal} 2,3,7,8 tetrachlorodibenzofuran (10{sup {minus}11} to 10{sup {minus}8} M) > {beta}-naphthoflavone (10{sup {minus}7} to 10{sup {minus}6} M) inhibited Vg synthesis in 17{beta}-estradiol treated liver cells. Potency of inhibition directly related to strength as an inducer of CYP1A1 protein. At 10-8 M, PCB congeners 77, 126, and 156 did not inhibit Vg synthesis and induced no or only moderate CYP1A1 protein. At 10-8 M, PCB congener 114, a weak CYP1A1 inducer, potentiated Vg synthesis relative to cells treated with 17{beta}-estradiol alone. This study increases their understanding of the consequences of hepatic CYP1A1 induction, forewarns of reproductive impairment of sexually maturing fishes exposed to CYP1A1 inducing compounds and argues for further, more detailed in vivo investigation.
Toxicogenomic profiling of the hepatic tumor promoters indole-3-carbinol, 17beta-estradiol and beta-naphthoflavone in rainbow trout.
Tilton, Susan C; Givan, Scott A; Pereira, Cliff B; Bailey, George S; Williams, David E
Indole-3-carbinol (I3C), from cruciferous vegetables, has been found to suppress or enhance tumors in several animal models. We previously reported that dietary I3C promotes hepatocarcinogenesis in rainbow trout (Oncorhynchus mykiss) at concentrations that differentially activated estrogen receptor (ER) or aryl hydrocarbon receptor (AhR)-mediated responses based on individual protein biomarkers. In this study, we evaluated the relative importance of these pathways as potential mechanisms for I3C on a global scale. Hepatic gene expression profiles were examined in trout after dietary exposure to 500 and 1500 ppm I3C and 3,3'-diindolylmethane (DIM), a major in vivo component of I3C, and were compared to the transcriptional signatures of two model hepatic tumor promoters: 17beta-estradiol (E2), an ER agonist, and beta-naphthoflavone, an AhR agonist. We demonstrate that I3C and DIM acted similar to E2 at the transcriptional level based on correlation analysis of expression profiles and clustering of gene responses. Of the genes regulated by E2 (fold change >or =2.0 or < or =0.50), most genes were regulated similarly by DIM (87-92%) and I3C (71%), suggesting a common mechanism of action. Of interest were upregulated genes associated with signaling pathways for cell growth and proliferation, vitellogenesis, and protein folding, stability, and transport. Other genes downregulated by E2, including those involved in acute-phase immune response, were also downregulated by DIM and I3C. Gene regulation was confirmed by qRT-PCR and Western blot. These data indicate I3C promotes hepatocarcinogenesis through estrogenic mechanisms in trout liver and suggest DIM may be an even more potent hepatic tumor promoter in this model. PMID:16192472
Transport of 17beta-estradiol and testosterone in a field lysimeter
Technology Transfer Automated Retrieval System (TEKTRAN)
17ß-estradiol (E2) and testosterone (T) are present in sources such as waste treatment effluent and manures, and can potentially disrupt aquatic organisms at low concentrations. Laboratory studies consistently indicate limited mobility and rapid attenuation of E2 and T in soils; however, these hormo...
Stimulation of catecholamine synthesis through unique estrogen receptors in the bovine adrenomedullary plasma membrane by 17{beta}-estradiol
Yanagihara, Nobuyuki [Department of Pharmacology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555 (Japan)]. E-mail: email@example.com; Liu, Minhui [Department of Pharmacology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555 (Japan); Toyohira, Yumiko [Department of Pharmacology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555 (Japan); Tsutsui, Masato [Department of Pharmacology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555 (Japan); Ueno, Susumu [Department of Pharmacology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555 (Japan); Shinohara, Yuko [Department of Pharmacology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555 (Japan); Takahashi, Kojiro [Department of Hospital Pharmacy, University Hospital, University of Occupational and Environmental Health, 1-1, Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555 (Japan); Tanaka, Kazumi [Department of Pharmacology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555 (Japan)
Incubation of cultured bovine adrenal medullary cells with 17{beta}-estradiol (E{sub 2}) (0.3-100 nM) or membrane-impermeable E{sub 2}-bovine serum albumin (100 nM) acutely increased {sup 14}C-catecholamine synthesis from [{sup 14}C]tyrosine. The stimulatory effect of E{sub 2} was not inhibited by ICI182,780, a nuclear estrogen receptor inhibitor. E{sub 2} also increased tyrosine hydroxylase activity and p44/42MAPK phosphorylation, the former of which was attenuated by U0126, an inhibitor of p44/42MAPK kinase. The plasma membrane isolated from the gland showed two classes of specific binding sites of [{sup 3}H]E{sub 2} with apparent K {sub d}s of 3.2 and 106 nM, and B {sub max}s of 0.44 and 8.5 pmol/mg protein, respectively. The high-affinity binding of [{sup 3}H]E{sub 2} was most strongly inhibited by E{sub 2} and phytoestrogens, and to lesser extents by other steroid hormones, while it was enhanced by ICI182,780 and environmental estrogenic pollutants. These findings suggest that E{sub 2} acutely stimulates catecholamine synthesis via activation of p44/42MAPK through unique estrogen receptors in the plasma membrane of bovine adrenal medulla.
Maternally derived testosterone and 17beta-estradiol in the eggs of Arctic-breeding glaucous gulls in relation to persistent organic pollutants.
Verboven, Nanette; Verreault, Jonathan; Letcher, Robert J; Gabrielsen, Geir W; Evans, Neil P
It is largely unknown if and how persistent organic pollutants (POPs) affect the transfer of maternal hormones to eggs. This occurs despite an increasing number of studies relating environmental conditions experienced by female birds at the time of egg formation to maternal hormonal effects. Here we report the concentrations of maternal testosterone, 17beta-estradiol and major classes of POPs (organochlorines, brominated flame retardants and metabolically-derived products) in the yolk of unincubated, third-laid eggs of the glaucous gull (Larus hyperboreus), a top-predator in the Arctic marine environment. Controlled for seasonal and local variation, positive correlations were found between the concentrations of certain POPs and testosterone. Contaminant-related changes in the relative concentrations of testosterone and 17beta-estradiol were also observed. In addition, yolk steroid concentrations were associated with contaminant profiles describing the proportions of different POPs present in the yolk. Eggs from nests in which two sibling eggs hatched or failed to hatch differed in POP profiles and in the relative concentrations of testosterone and 17beta-estradiol. Although the results of this correlative study need to be interpreted with caution, they suggest that contaminant-related changes in yolk steroids may occur, possibly affecting offspring performance over and above toxic effects brought about by POPs in eggs. PMID:18550446
Evaluation of the primary humoral immune response following exposure of male rats to 17beta-estradiol or flutamide for 15 days.
Ladics, G S; Smith, C; Nicastro, S C; Loveless, S E; Cook, J C; O'Connor, J C
There is a concern that certain industrial chemicals found in the environment may mimic or antagonize endogenous hormones and adversely affect the endocrine as well as the immune system. The objective of this study was to determine if exposure of Crl:CD (SD)BR male rats to 17beta-estradiol (17beta-E2), an estrogen receptor agonist, or flutamide (FLUT), an androgen receptor antagonist, would significantly alter the primary IgM humoral immune response to sheep red blood cells (SRBC). This study was conducted in the context of a male in vivo Tier I battery designed to identify endocrine-active compounds (EACs). The Tier I male battery consists of organ weights coupled with a comprehensive hormonal assessment. Rats were dosed by the intraperitoneal route for 15 days with vehicle or 0.001, 0.0025, 0.0075, or 0.050 mg/kg/day 17beta-E2 or 0.25, 1, 5, or 20 mg/kg/day FLUT. Six days prior to termination, selected rats were injected intravenously with SRBC for assessment of humoral immune function. Spleen cell number and spleen and thymus weights were obtained. Serum was analyzed for anti-SRBC IgM antibody by using an enzyme-linked immunosorbent assay. At 0.050 mg/kg/day 17beta-E2, mean final body and absolute thymus weights were significantly decreased to 84 and 65% of control, respectively. 17beta-E2 did not significantly alter spleen weight, spleen cell number, or the primary IgM humoral immune response to SRBC. The no-observed-adverse-effect level (NOAEL) for immune system alteration was 0.050 mg/kg/day 17beta-E2 since the decrease in absolute thymus weight was judged to be secondary to the decrements in body weight. In the Tier I male battery, responses to 17beta-E2 included decreased absolute testis and epididymis weights, decreased relative accessory sex gland unit weights, hormonal alterations (decreased serum testosterone (T), dihydrotestosterone (DHT), and luteinizing hormone (LH), and increased serum prolactin and E2 levels). The lowest-observed-adverse-effect level (LOAEL) for the reproductive indices was 0.001 mg/kg/day 17beta-E2 based on the hormonal alterations seen at this level; no NOAEL was established. Exposure to FLUT did not significantly alter mean final body, spleen, or absolute thymus weights, spleen cell number, or the primary IgM humoral immune response to SRBC. A significant increase (118% of control) in relative thymus weight was observed at 20 mg/kg/day FLUT. The NOAEL for immune system alteration was 5 mg/kg/day FLUT based on the increased relative thymus weights that were judged to be compound-related. In the Tier I male battery, responses to FLUT included decreased absolute epididymis and relative accessory sex gland unit weights and hormonal alterations (increased serum T, DHT, E2, and LH, and decreased follicle stimulating hormone levels). The LOAEL for the reproductive indices was 0.25 mg/kg/day FLUT based on the hormonal alterations seen at this level; no NOAEL was established. Based on these data, the reproductive and not the immune system appears to be the primary target organ of toxicity in young adult male rats treated with either 17beta-E2 or FLUT. PMID:9928670
Low 17beta-estradiol levels in CNR1 knock-out mice affect spermatid chromatin remodeling by interfering with chromatin reorganization.
Cacciola, Giovanna; Chioccarelli, Teresa; Altucci, Lucia; Ledent, Catherine; Mason, J Ian; Fasano, Silvia; Pierantoni, Riccardo; Cobellis, Gilda
The type 1-cannabinoid receptor, CNR1, regulates differentiation of spermatids. Indeed, we have recently reported that the genetic inactivation of Cnr1 in mice influenced chromatin remodeling of spermatids, by reducing histone displacement and then sperm chromatin quality indices (chromatin condensation and DNA integrity). Herein, we have studied, at both central and testicular levels, the molecular signals potentially involved in histone displacement. In particular, investigation of the neuroendocrine axis involved in estrogen production demonstrated down-regulation of the axis supporting FSH/estrogen secretion in Cnr1-knockout male mice. Conversely, Cnr1-knockout male mice treated with 17beta-estradiol showed a weak increase of pituitary Fsh-beta subunit mRNA levels and a rescue of sperm chromatin quality indices demonstrating that estrogens, possibly in combination with FSH secretion, play an important role in regulating chromatin remodeling of spermatids. PMID:23677985
Identification of centrarchid hepcidins and evidence that 17beta-estradiol disrupts constitutive expression of hepcidin-1 and inducible expression of hepcidin-2 in largemouth bass (Micropterus salmoides).
Robertson, Laura S; Iwanowicz, Luke R; Marranca, Jamie Marie
Hepcidin is a highly conserved antimicrobial peptide and iron-regulatory hormone. Here, we identify two hepcidin genes (hep-1 and hep-2) in largemouth bass (Micropterus salmoides) and smallmouth bass (Micropterus dolomieu). Hepcidin-1 contains a putative ATCUN metal-binding site in the amino-terminus that is missing in hepcidin-2, suggesting that hepcidin-1 may function as an iron-regulatory hormone. Both hepcidins are predominately expressed in the liver of largemouth bass, similar to other fish and mammals. Experimental exposure of pond-raised largemouth bass to 17beta-estradiol and/or the bacteria Edwardsiella ictaluri led to distinct changes in expression of hep-1 and hep-2. Estradiol reduced the constitutive expression of hep-1 in the liver. Bacterial exposure induced expression of hep-2, suggesting that hepcidin-2 may have an antimicrobial function, and this induction was abolished by estradiol. To our knowledge, this is the first report of the regulation of hepcidin expression by estradiol in either fish or mammals. PMID:19376234
Two experiments were performed to determine the rate of vitellogenin plasma accumulation and clearance in male sheepshead minnows (Cyprinodon variegatus) during and after exposure to either 17b-estradiol (E2) or para-nonylphenol (p-NP). Adult fish were continuously exposed to aqu...
17beta-estradiol matrixpatch removal and reapplication in postmenopausal women: theoretical predictions with an oscillating diffusion coefficient model.
Rohr, Uwe D; Saeger-Lorenz, Katrin
The pharmacokinetic performance of a matrix system for transdermal beta-estradiol (E(2)) delivery after multiple consecutive dosing in postmenopausal women undergoing hormone replacement therapy was investigated. The E(2) plasma profiles determined during the third application in 16 postmenopausal women were compared with results obtained in a published clinical study using the same patch in 24 postmenopausal women without E(2) pretreatment; they were compared with a theoretical diffusion/pharmacokinetic model. A conventional theoretical model with constant model parameter (CPM) obtained from in vitro mass balance experiments in a Franz cell type set up described successfully the transdermal E(2) bioavailability parameter AUC(0-96h) (4341.9 +/- 1513.1; calculated 4250.8) and C(average) (45.0 +/- 13.2; calculated 41.2). Also, experimentally, there was no significant drop in E(2) plasma values after patch removal and reapplication; this was corroborated by calculations. Accumulation of E(2) did not occur when several patches were applied consecutively over a period of 3 weeks. Steady state was achieved following application of the first patch. However, the differences between recorded E(2) plasma profiles and theoretical results detected at specific measurement points cannot be explained by the CPM model. Experimentally obtained plasma profiles were always lower in the morning and higher in the evening than predicted on the basis of the model. Measurements of in vivo skin temperature in the postmenopausal women showed oscillating temperature profiles in the form of a cosinor function: The temperature mesor of untreated postmenopausal women was 34.8 degrees C with an acrophase at 17.0 o'clock (95% CI: 14.30-19.30) and an amplitude of +/- 0.4 degrees C (p = 0.1). During the application of the patch the average temperature next to a patch rose 0.3 degrees C, which was statistically significant (p = 0.1). In the skin under the application of the matrix patch a mesor temperature was detected as 35.6 degrees C with an amplitude of +/- 0.5 degrees C with an acrophase at 17.51 o'clock (95% CI: 14.30-21.00) (p = 0.05). The temperature period was 24 h for all measurements and the maximum temperature was observed at about 16.30 h, and a minimum at about 5.00 h. A linear dependency was detected in in vitro experiments between the log of E(2) permeability and the temperature for stripped skin, epidermis/dermis layer, as well as for the matrix. Modeling of E(2) plasma profiles with oscillating diffusion coefficients (ODM1) with a sine wave function results in this equation: D(1) = D(0x) + Da(x).sin(k.t). D(0x) is the diffusion coefficient determined at 35.6 degrees C, k is 1/24 h, D(a) is the diffusion coefficient of the temperature amplitude, h is hour, and x stands for the respective diffusion layer. It was shown that the experimental E(2) plasma profile variations are more pronounced than can simply be explained by skin temperature variations alone (ODM1 model). A simplex fit with an oscillating diffusion coefficient in the form of a sine wave function for the stratum corneum (ODM2 model) resulted in a temperature amplitude of 1.1 degrees C, about twice as high as was determined in the in vivo measurements (ODM2 model). Therefore, other circadian parameterlike blood flow might superimpose the temperature profile. The improvement in data analysis by incorporating oscillating diffusion coefficients (ODM1 and 2) over CPM was judged from a comparison of experimental data with the calculated plasma profiles with the AIC, Akaikes model selection criterion, which allows ranking between models because it is independent of the scaling of the data points. ODM1 and ODM2 improved the data analysis over CPM by allowing better calculation of experimental C(max), t(max), the time to reach to C(max), and the fluctuation, f. No difference between CPM, ODM1, or ODM2 was found for the bioavailability parameter C(average) and AUC(0-96h). PMID:11920768
Beneficial effect of 17{beta}-estradiol on hyperglycemia and islet {beta}-cell functions in a streptozotocin-induced diabetic rat model
Yamabe, Noriko; Kang, Ki Sung; Zhu Baoting, E-mail: firstname.lastname@example.com
The modulating effect of estrogen on glucose homeostasis remains a controversial issue at present. In this study, we sought to determine the beneficial effect of 17{beta}-estradiol (E{sub 2}) on hyperglycemia and islet {beta}-cell functions in streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were injected i.p. with STZ to induce a relatively mild diabetic condition. The rats were then treated with E{sub 2} orally at 500 {mu}g/kg body weight/day for 15 days to evaluate the modulating effect on hyperglycemia, insulin secretion, and islet {beta}-cell proliferation. E{sub 2} administration for 10 days significantly lowered plasma glucose levels, increased plasma insulin levels, and improved glucose tolerance by attenuating insulin response to oral glucose loading. These beneficial effects of E{sub 2} were accompanied by increases in islet number and volume, rate of islet cell proliferation, and the amount of insulin secreted. The growth-stimulatory effect of E{sub 2} on islet cells was linked to the functions of the estrogen receptor {alpha}. Notably, these protective effects of E{sub 2} on diabetic conditions were basically not observed when the STZ-treated rats had a more severe degree of islet damage and hyperglycemia. Taken together, we conclude that E{sub 2} can promote the regeneration of damaged pancreatic islets by stimulating {beta}-cell proliferation in diabetic rats, and this effect is accompanied by improvements in glucose tolerance and a decrease in plasma glucose levels. These findings suggest that oral administration of E{sub 2} may be beneficial in diabetic patients with an accelerated loss of islet {beta}-cells.
In vitro antiestrogenic effects of aryl methyl sulfone metabolites of polychlorinated biphenyls and 2,2-bis(4-chlorophenyl)-1,1-dichloroethene on 17beta-estradiol-induced gene expression in several bioassay systems.
Letcher, Robert J; Lemmen, Josephine G; van der Burg, Bart; Brouwer, Abraham; Bergman, Ake; Giesy, John P; van den Berg, Martin
Methylsulfonyl (MeSO(2)) metabolites of polychlorinated biphenyls (PCBs) and 2,2-bis(4-chlorophenyl)-1,1-dichloroethene (4,4'-DDE), itself a metabolite of the insecticide 4,4'-DDT, are emerging as a major class of contaminants in the tissues of wildlife and humans. We investigated the antiestrogenic capacity and potencies of 3'- and 4'-MeSO(2)-2,2',4,5,5'-pentachlorobiphenyl (CB101) and -2,2',4,5'-tetrachlorobiphenyl (CB49), which are among the most environmentally persistent MeSO(2)-PCBs, and 3-MeSO(2)-4,4'-DDE on estrogen receptor (ER)-dependent gene expression in four cell-based bioassay systems. Congener- and concentration-dependent antagonism of 17beta-estradiol (E2)-induced gene expression, rather than induction of ER-dependent gene expression, was observed for the MeSO(2)-PCBs on lucifierase activity in stably transfected human breast adenocarcinoma T47D cells (ER-CALUX) and vitellogenin (vtg) production in primary hepatocytes from male carp fish (Cyprinus carpio) (CARP-HEP/vtg). 4'-MeSO(2)-CB101 and -CB49 had the highest antagonistic potency (i.e., maximum inhibition of about 70%, LOECs of 1.0 microM and 2.5 microM), whereas 3'-MeSO(2)-CB101 and -CB49 were less antagonistic; the precursor CB101 and MeSO(2)-PCB analog MeSO(2)-2,5-dichlorobenzene had no effect. Relative to the 4-MeSO(2)-PCBs, tamoxifen (IC(50), 0.06 microM and 0.7 microM) was about 40 and 7 times more potent in the ER-CALUX and CARP-HEP/vtg assays, respectively. Congener- and concentration-dependent effects on aryl hydrocarbon receptor-mediated induction of EROD activity (carp hepatocytes), luciferase expression (H4IIE rat hepatoma [H4IIE.luc] cell line), or cell viability were not observed. 3-MeSO(2)-4,4'-DDE was neither estrogenic nor antiestrogenic in either of the bioassays. Inhibitory trends for the MeSO(2)-PCBs in a bioassay based on stably transfected human embryonic kidney cell (HEK293-ERalpha-ERE) were similar to the ER-CALUX and CARP-HEP/vtg bioassays, whereas the antagonism was weaker in a related HEK293-ERbeta-ERE bioassay. Our findings suggest that the 4'-MeSO(2)-PCBs are antiestrogenic in vitro via a reversible or surmountable interaction with fish or human ER, and that the interaction with human ERalpha is apparently favored over ERbeta. MeSO(2)-PCB metabolites are persistent and bioaccumulative contaminants, and therefore, could be potentially active as environmental antiestrogens in wildlife and humans. PMID:12377985
Environmental Technology Verification Report for Abraxis 17ß-Estradiol (E2) Magnetic Particle Enzyme-Linked Immunosorbent Assay (ELISA) Test Kits
The EPA's National Risk Management Research Laboratory (NRMRL) and its verification organization partner, Battelle, operate the Advanced Monitoring Systems (AMS) Center under ETV. The AMS Center recently evaluated the performance of the Abraxis 17(beta)-estradiol (E2) magnetic p...
An inter-laboratory study on the variability in measured concentrations of 17Beta-estradiol, testosterone and 11-ketotestosterone in white sucker: implications and recommendations
Endocrine-disrupting chemicals (EDCs) are exogenous substances that can lead to impacts on the reproduction of fish sometimes by altering circulating concentrations of 17â-estradiol (E2), testosterone (T) and 11-ketotestosterone (11-KT). Common methods to measure steroids in pla...
FoxM1 influences embryo implantation and is regulated by 17 beta-estradiol and progesterone in mouse uteri and endometrium cells
Xie, Yunpeng; Cui, Dan; Kong, Ying
To be a successful implantation, endometrial receptivity should be established. Forkhead box M1 (FoxM1) is described as a major oncogenic transcription factor in tumor initiation, promotion, and progression. FoxM1 regulates the expression of lots of targeted genes important to cell differentiation, proliferation and apoptosis; cell-cycle progression; and tumor angiogenesis, migration, invasion, and metastasis. According to these functions, we believe that FoxM1 should also play an essential role in embryo implantation. To test our hypothesis, we observed the expression and distribution of FoxM1 during the early pregnancy of mouse. Then, we used Immunohistochemistry to examine the expression of FoxM1 induced by E2 and/or P4 in the ovariectomized mouse uterus and human endometrium cells. This study further investigated whether FoxM1 was an important factor in the implantation. Our results showed that FoxM1 expressed in the mouse uterus during early pregnancy (Day 1 to 5). The expression of FoxM1 gradually increased along pregnancy process; FoxM1 expression could be increased by E2. On the contrary, FoxM1 expression could be decreased by P4 and E2 plus P4. We also detected the proliferation of human endometrium cells. We found that E2 might promote cells proliferation, while P4 and E2 plus P4 inhibited cells proliferation; Inhibiting FoxM1 could interfere the embryo implantation of mouse. Amplification or inhibiting of FoxM1 in JAR cells can increase or decrease the adhesion rate to Rl95-2 and HEC-1A cells separately. Our data indicate that FoxM1 might play an important role during the process of mouse embryo implantation. PMID:25400737
The chemical behavior of estrone and 17beta-estradiol in the environment
Ullman, Jeffrey Layton
not affect mineralization rates. The compounds had partition coefficients ranging from 2 to 4.4 mL g-1, depending on soil characteristics. Estrone and 17�²-estradiol had a higher absorptivity to soils with greater clay content and organic matter. Once...
Lipocalin 2: a "sexy" adipokine that regulates 17Beta-estradiol and obesity
Technology Transfer Automated Retrieval System (TEKTRAN)
In this article we review the findings of Guo et. al. (Endocrinology, 153: 1183-1193) that the protein, Lipocalin 2 is more highly expressed in subcutaneous adipose tissue than in gondal tissue of female mice. Of particular interest is that the paper by Guo et. al. observed that ablation of the Lip...
Assessing the effects of exposure timing on biomarker expression using 17beta-estradiol
Temporal and spatial variability in estrogenicity has been documented for many treated wastewater effluents with the consequences of this variability on the expression of biomarkers of endocrine disruption being largely unknown. Laboratory exposure studies usually utilize constan...
The chemical behavior of estrone and 17beta-estradiol in the environment
Ullman, Jeffrey Layton
H. ..................................................................................... 27 Fig. 2.2. Estrone concentration profile at pH 4 during irradiation with UV-light. ........... 28 Fig. 3.1. Sorption isotherms for (a) estrone and (b) 17?-estradiol in Tremona loamy fine sand (?), Weswood silty clay loam (?) and Houston Black...., 2004). Affirmation that local cattle operations generated elevated 17?- estradiol concentrations in karst aquifers denotes potential estrogenic contamination of groundwater systems (Peterson et al., 2000). Treatment of agriculturally generated...
Ovariectomy and 17 beta-Estradiol Replacement Do Not Alter beta-Amyloid Levels in Sheep Brain
Anna Barron; Martin Cake; Giuseppe Verdile; Ralph Martins
The benefits of estrogen replacement as a preventative treatment for Alzheimer's disease (AD) are subject to debate. Because the effects of estrogen depletion and replacement on accumulation of the neurotoxic ?-amyloid (A?) peptide in transgenic animal models of AD have been variable, we examined A? levels and oxidative stress in a nontransgenic animal model. Sheep have traditionally been used as
A Computational Model of the Hypothalamic-pituitary-gonadal Axis in Male Fathead Minnows Exposed to 17 | *alpha* | -ethinylestradiol and 17 | *beta* | -estradiol
Estrogenic chemicals in the aquatic environment have been shown to cause a variety of reproductive anomalies in fish including full sex reversal, intersex, and altered population sex ratios. Two estrogens found in the aquatic environment, 17-ethinylestradiol and 17â-estradiol, h...
Uterine physiological responses and global gene expression in ovariectomized (ovx) rats treated with soy protein isolate (spi) or 17Beta-estradiol
Technology Transfer Automated Retrieval System (TEKTRAN)
Concerns regarding increased endometrial cancer risk have been raised in women who consume soy products as the result of the estrogenicity of phytochemical components such as the isoflavones genistein and daidzein. Female Sprague-Dawley rats (N = 20/group) were fed AIN-93G diets with casein or SPI a...
DNA arrays to monitor gene expression in rat blood and uterus following 17-b-estradiol exposure - biomonitoring environmental effects using surrogate tissues John C. Rockett, Robert J. Kavlock, Christy R. Lambright, Louise G. Parks, Judith E. Schmid, Vickie S. Wilson, Carmen W...
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...
Hepatic gene expression following consumption of soy protein isolate in female sprague-dawley rats differs from that produced by 17beta-estradiol treatment
Technology Transfer Automated Retrieval System (TEKTRAN)
Although soy foods have been recognized as an excellent source of protein, there have been recent concerns regarding potential adverse effects of isoflavone phytochemicals found in soy products, which are known to bind and activate estrogen receptors. Here we used global hepatic gene expression prof...
Mammary gland morphology and gene expression differ in female rats treated with 17 beta-estradiol or fed soy protein isolate
Technology Transfer Automated Retrieval System (TEKTRAN)
Soy foods have been suggested to have both positive health benefits and potentially adverse effects as a result of their content of phytoestrogens. However, studies on the estrogenicity of soy foods are lacking. Here we directly compared the effects of soy protein isolate (SPI), the protein in soy i...
Modulation of vitellogenin synthesis through estrogen receptor beta-1 in goldfish (Carassius auratus) juveniles exposed to 17-{beta} estradiol and nonylphenol
Soverchia, L. [Dipartimento di Medicina Sperimentale e Sanita Pubblica, Universita degli Studi di Camerino, via Scalzino 3, 62032 Camerino (Monaco) (Italy); Ruggeri, B. [Dipartimento di Scienze Morfologiche e Biochimiche Comparate, Universita degli Studi di Camerino, via Camerini 2, 62032 Camerino (Monaco) (Italy); Palermo, F. [Dipartimento di Scienze Morfologiche e Biochimiche Comparate, Universita degli Studi di Camerino, via Camerini 2, 62032 Camerino (Monaco) (Italy); Mosconi, G. [Dipartimento di Scienze Morfologiche e Biochimiche Comparate, Universita degli Studi di Camerino, via Camerini 2, 62032 Camerino (Monaco) (Italy); Cardinaletti, G. [Dipartimento di Scienze Morfologiche e Biochimiche Comparate, Universita degli Studi di Camerino, via Camerini 2, 62032 Camerino (Monaco) (Italy); Scortichini, G. [Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Campo Boario, 64100 Teramo (Italy); Gatti, G. [Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', Campo Boario, 64100 Teramo (Italy); Polzonetti-Magni, A.M. [Dipartimento di Scienze Morfologiche e Biochimiche Comparate, Universita degli Studi di Camerino, via Camerini 2, 62032 Camerino (Monaco) (Italy)]. E-mail: email@example.com
Many synthetic chemicals, termed xenoestrogens, have been shown to interact as agonists with the estrogen receptor (ER) to elicit biological responses similar to those of natural hormones. To date, the regulation of vitellogenesis in oviparous vertebrates has been widely used for evaluation of estrogenic effects. Therefore, Carassius auratus juveniles were chosen as a fish model for studying the effects of estradiol-17{beta} and different concentrations (10{sup -6} and 10{sup -7} M) of 4-nonylphenol (4-NP) on the expression of liver ER{beta}-1 subtype; plasma vitellogenin and sex steroids (androgens and estradiol-17{beta}) were also evaluated together with the bioaccumulation process, through mass-spectrometry. C. auratus is a species widespread in the aquatic environment and, on the toxicological point of view, can be considered a good 'sentinel' species. Juveniles of goldfish were maintained in tanks with only tap water or water with different concentrations (10{sup -6} and 10{sup -7} M) of 4-nonylphenol (4-NP), or 10{sup -7} M of estradiol-17{beta}. After 3 weeks of treatment, animals were anesthetized within 5 min after capture, and blood was immediately collected into heparinized syringes by cardiac puncture and stored at -70 deg. C; the gonads were fixed, then frozen and stored at -70 deg. C; the whole fish, liver, and muscle tissues were harvested and immediately stored at -70 deg. C for molecular biology experiments and bioaccumulation measurements. The estrogenic effects of 4-NP were evidenced by the presence of plasma vitellogenin in juveniles exposed both to estradiol-17{beta} and the two doses of 4-NP; moreover, exposure to 4-NP also increased aromatization of androgens, as suggested by decreasing androgens and increasing estradiol-17{beta} plasma levels. The changes of these parameters were in agreement with the increasing transcriptional rate of ER{beta}-1 mRNA in the liver, demonstrating that both estradiol-17{beta} and 4-NP modulate the vitellogenin rate through interaction with the ER{beta}-1 subtype. The present study also suggests that 4-NP at the concentration of 10{sup -6} M bioaccumulates in the liver.
Pathogenic infection confounds induction of the estrogenic biomarker vitellogenin in rainbow trout
Technology Transfer Automated Retrieval System (TEKTRAN)
To examine the behavior of the estrogenic biomarker vitellogenin (VTG) under the combined impact of estrogens and pathogens, parasite-infected or noninfected rainbow trout were exposed to two doses of 17 beta-estradiol (E2). Infected and E2-exposed fish showed significantly lower hepatic VTG mRNA le...
Differential effects of short term feeding of a soy protein isolate diet and estrogen treatment on bone in the pre-pubertal rat
Technology Transfer Automated Retrieval System (TEKTRAN)
Beneficial effects of a soy diet on bone quality have been assumed to be due to the putative estrogenic actions of isoflavones. We studied the effects of soy protein isolate (SPI) on bone quality and compared these effects to 17 beta-estradiol (E2) in pre-pubertal rats. Female rats were weaned to a ...
Sorption, fate, and transport of endogenous steroid hormones in soils
Technology Transfer Automated Retrieval System (TEKTRAN)
The natural hormones 17 beta-estradiol (E2) and testosterone (T) are present in animal manures that are applied to agricultural land as fertilizer and, potentially, may act as endocrine disruptors. Laboratory incubation, batch, and column experiments have been conducted on a series of soils and wer...
Kawato, Suguru
076 1. E2 E2 E2 E2 2. E2 E2 2 E2 1 1-10 nM E2 5), 7) E2 30 E2 7) E2 512076-0792011 Modulation of Learning and Memory slowly but also rapidly. Slow actions of estradiol (E2) occur via nuclear receptors (ER), while rapid E2
Estrogen Receptor Pathway Is Involved in the Regulation of Calbindin-D9k in the Uterus of Immature Rats
Geun-Shik Lee; Hoe-Jin Kim; Yong-Woo Jung; Kyung-Chul Choi; Eui-Bae Jeung
It has been demonstrated in our previous studies that Calbindin- D9k (CaBP-9k) is a potent biomarker for screening estrogen-like chemicals in the rat model. Although treatments with 17beta- estradiol (E2) and endocrine disrupting compounds resulted in the up-regulation of uterine CaBP-9k, the mechanism of CaBP-9k induction by these compounds through two subtypes of estrogen receptors (ERa and ERb) is unclear.
Estradiol-induced enhancement of object memory consolidation involves hippocampal extracellular signal-regulated kinase activation and membrane-bound estrogen receptors.
Fernandez, Stephanie M; Lewis, Michael C; Pechenino, Angela S; Harburger, Lauren L; Orr, Patrick T; Gresack, Jodi E; Schafe, Glenn E; Frick, Karyn M
The extracellular signal-regulated kinase (ERK) pathway is critical for various forms of learning and memory, and is activated by the potent estrogen 17beta-estradiol (E(2)). Here, we asked whether E(2) modulates memory via ERK activation and putative membrane-bound estrogen receptors (ERs). Using ovariectomized mice, we first demonstrate that intraperitoneal injection of 0.2 mg/kg E(2) significantly increases dorsal hippocampal levels of phosphorylated ERK protein 1 h after injection. Second, we show that E(2) administered intraperitoneally (0.2 mg/kg) or via intrahippocampal infusion (5.0 microg/side) immediately after training in an object recognition task significantly enhances memory retention, and that the beneficial effect of intraperitoneal E(2) is blocked by dorsal hippocampal inhibition of ERK activation. Third, using bovine serum albumin-conjugated 17beta-estradiol (BSA-E(2)), we demonstrate that E(2) binding at membrane-bound ERs can increase dorsal hippocampal ERK activation and enhance object memory consolidation in an ERK-dependent manner. Fourth, we show that this effect is independent of nuclear ERs, but is dependent on the dorsal hippocampus. By demonstrating that E(2) enhances memory consolidation via dorsal hippocampal ERK activation, this study is the first to identify a specific molecular pathway by which E(2) modulates memory and to demonstrate a novel role for membrane-bound ERs in mediating E(2)-induced improvements in hippocampal memory consolidation. PMID:18753366
NASA Technical Reports Server (NTRS)
Kelley, Richard L.
The Astro-E2 observatory is a rebuild of the original Astro-E observatory that was lost during launch in February 2000. It is scheduled for launch into low earth orbit on a Japanese M-V rocket in early 2005. The Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, is developing the observatory with major contributions from the US. The three instruments on the observatory are the high-resolution x-ray spectrometer (the XRS) featuring a 30-pixel x-ray microcalorimeter array, a set of four CCD cameras (the XIS) and a combination photo-diode/scintillator detector system (the HXD) that will extend the band pass up to nearly 700 keV. A significant feature of Astro-E2 is that all of the instruments are coaligned and operated simultaneously. With its high spectral resolution and collecting area for spectroscopy above 1 keV, Astro-E2 should enable major discovery space and pioneer new technology for use in space. Prime areas for investigation are supernova remnants, active galaxies and the measurement of black hole properties via relativistically-broadened Fe-K emission galaxies. A number of enhancements have been made for the Astro-E2/XRS, including a higher resolution microcalorimeter array, ii mechanical cooler for longer cryogen life, and an improved in-flight calibration system. The Astro-E2/XIS has also been improved to include two back-side-illuminated CCDs to enhance the low energy response. Improvements have also been made to the x-ray mirrors used for both the XRS and XIS to sharpen the point spread function and reduce the effects of stray light. In this talk we will present the essential features of Astro-E2, paying particular attention to the enhancements, and describe the major scientific strengths of the observatory.
Estradiol prevents olfactory dysfunction induced by A-? 25–35 injection in hippocampus
Background Some neurodegenerative diseases, such as Alzheimer and Parkinson, present an olfactory impairment in early stages, and sometimes even before the clinical symptoms begin. In this study, we assess the role of CA1 hippocampus (structure highly affected in Alzheimer disease) subfield in the rats' olfactory behavior, and the neuroprotective effect of 17 beta estradiol (E2) against the oxidative stress produced by the injection of amyloid beta 25–35. Results 162 Wistar rats were ovariectomized and two weeks after injected with 2 ?l of amyloid beta 25–35 (A-?25–35) in CA1 subfield. Olfactory behavior was evaluated with a social recognition test, odor discrimination, and search tests. Oxidative stress was evaluated with FOX assay and Western Blot against 4-HNE, Fluoro Jade staining was made to quantify degenerated neurons; all these evaluations were performed 24 h, 8 or 15 days after A-?25–35 injection. Three additional groups treated with 17 beta estradiol (E2) were also evaluated. The injection of A-?25–35 produced an olfactory impairment 24 h and 8 days after, whereas a partial recovery of the olfactory behavior was observed at 15 days. A complete prevention of the olfactory impairment was observed with the administration of E2 two weeks before the amyloid injection (A-?25–35 24 h?+?E2) and one or two weeks after (groups 8 A-? +E2 and 15 A-? +E2 days, respectively); a decrease of the oxidative stress and neurodegeneration were also observed. Conclusions Our finding shows that CA1 hippocampus subfield plays an important role in the olfactory behavior of the rat. The oxidative stress generated by the administration of A-?25–35 is enough to produce an olfactory impairment. This can be prevented with the administration of E2 before and after amyloid injection. This suggests a possible therapeutic use of estradiol in Alzheimer's disease. PMID:24059981
E2I EPRI Assessment Offshore Wave Energy Conversion Devices
E2I EPRI Assessment Offshore Wave Energy Conversion Devices Report: E2I EPRI WP 004 US Rev 1 #12;E2I EPRI Assessment - Offshore Wave Energy Conversion Devices Table of Contents Introduction ............................................................................... 26 Appendix E - Orecon
Ultrafast Electron Pulse (e,2e) Processes
NASA Astrophysics Data System (ADS)
Shao, Hua-Chieh; Starace, Anthony; Madsen, Lars
Techniques for producing ultrafast electron pulses have been proposedootnotetextP. Baum and A.H. Zewail, Proc. Natl. Acad. Sci. U.S.A. 104, 18409 (2007); S.A. Hilbert, C. Ulterwaal, B. Barwick, H. Betalaan, and A.H. Zewail, ibid. 106, 10558 (2009). and prospects for using such pulses to image electron dynamics in the H atom and the hydrogen molecular ion have been theoretically demonstrated.ootnotetextH.-C. Shao and A.F. Starace, Phys. Rev. Lett. 105, 263201 (2010). The (e,2e) process provides a means to directly image the momentum distribution of the target.ootnotetextM.A. Coplan, J.H. Moore, and J.P. Doering, Rev. Mod. Phys. 66, 985 (1994). We explore here the possibility of observing the time dependence of a coherent superposition of target orbitals by means of the (e,2e) process with ultrafast incident electron pulses. Using scattering theory for a longitudinally coherent beam,ootnotetextF. Robicheaux, Phys. Rev. A 62, 062706 (2000). we find that the momentum distribution of a coherent state of the H atom can be retrieved.
Magnetic reversal in Dy-doped DyF e2/YF e2 superlattice films
NASA Astrophysics Data System (ADS)
Stenning, G. B. G.; Bowden, G. J.; de Groot, P. A. J.; van der Laan, G.; Figueroa, A. I.; Bencok, P.; Steadman, P.; Hesjedal, T.
Reversible magnetic exchange springs can be formed in the magnetically soft YF e2 layers of epitaxial DyF e2/YF e2 multilayer films. Here we show that the insertion of just two monolayers of DyF e2 , placed directly in the middle of the YF e2 layers, brings about substantial changes. Results are presented for a Dy-doped (110)-oriented [DyFe2(60Ĺ) /YFe2(120 Ĺ ) /DyFe2(8 Ĺ ) /YFe2(120 Ĺ ) ] 15 multilayer film, measured at 100 K in fields of up to ±10 T. Using bulk magnetometry, micromagnetic modeling, and Dy-specific x-ray magnetic circular dichroism, it is shown that Dy doping substantially increases the number of spin states available to the system. Altogether 12 distinct spring states are identified which bring additional complexity to the magnetic reversal process. In particular, the exchange springs are no longer reversible, exhibiting magnetic exchange-spring collapse. Full and partial magnetic loops are presented for fields applied along the in-plane easy [001] axis and the in-plane hard [1 Ż10 ] axis. In particular, it is demonstrated that exchange-spring collapse is sharpest when the field is applied along a hard in-plane [1 Ż10 ] axis.
Mouse Development with a Single E2F Activator
Tsai, Shih-Yin; Opavsky, Rene; Sharma, Nidhi; Wu, Lizhao; Naidu, Shan; Nolan, Eric; Feria-Arias, Enrique; Timmers, Cynthia; Opavska, Jana; de Bruin, Alain; Chong, Jean-Leon; Trikha, Prashant; Fernandez, Soledad A.; Stromberg, Paul; Rosol, Thomas J.; Leone, Gustavo
The E2F family is conserved from C. elegans to mammals with some family members having transcription activation functions and others having repressor functions1, 2. Whereas C. elegans3 and Drosophila melanogaster4, 5 have a single E2F activator and repressor proteins, mammals evolved to have at least three activator and five repressor proteins1, 2, 6. Why such genetic complexity evolved in mammals is not known. To begin to evaluate this genetic complexity, we targeted the inactivation of the entire subset of activators, E2f1, E2f2, E2f3a and E2f3b, singly or in combination in mice. We demonstrate that E2f3a is sufficient to support mouse embryonic and postnatal development. Remarkably, expression of E2f3b or E2f1 from the E2f3a locus (E2f3a3bki; E2f3a1ki) suppressed all the postnatal phenotypes associated with the inactivation of E2f3a. We conclude that there is significant functional redundancy among activators and that the specific requirement for E2f3a during postnatal development is dictated by regulatory sequences governing its selective spatiotemporal expression and not by its intrinsic protein functions. These findings provide a molecular basis for the observed specificity among E2F activators during development. PMID:18594513
Mouse development with a single E2F activator.
Tsai, Shih-Yin; Opavsky, Rene; Sharma, Nidhi; Wu, Lizhao; Naidu, Shan; Nolan, Eric; Feria-Arias, Enrique; Timmers, Cynthia; Opavska, Jana; de Bruin, Alain; Chong, Jean-Leon; Trikha, Prashant; Fernandez, Soledad A; Stromberg, Paul; Rosol, Thomas J; Leone, Gustavo
The E2F family is conserved from Caenorhabditis elegans to mammals, with some family members having transcription activation functions and others having repressor functions. Whereas C. elegans and Drosophila melanogaster have a single E2F activator protein and repressor protein, mammals have at least three activator and five repressor proteins. Why such genetic complexity evolved in mammals is not known. To begin to evaluate this genetic complexity, we targeted the inactivation of the entire subset of activators, E2f1, E2f2, E2f3a and E2f3b, singly or in combination in mice. We demonstrate that E2f3a is sufficient to support mouse embryonic and postnatal development. Remarkably, expression of E2f3b or E2f1 from the E2f3a locus (E2f3a(3bki) or E2f3a(1ki), respectively) suppressed all the postnatal phenotypes associated with the inactivation of E2f3a. We conclude that there is significant functional redundancy among activators and that the specific requirement for E2f3a during postnatal development is dictated by regulatory sequences governing its selective spatiotemporal expression and not by its intrinsic protein functions. These findings provide a molecular basis for the observed specificity among E2F activators during development. PMID:18594513
([ital e],2[ital e]) spectroscopy
Coplan, M.A. (Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742 (United States)); Moore, J.H. (Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742 (United States)); Doering, J.P. (Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218 (United States))
Most of our knowledge of the electronic structure of atoms and molecules is derived from excitation energies and transition probabilities. These observable quantities are related to the electronic wave functions by integrals over unmeasured variables. Another observable more directly related to the wave function than energy or transition probability is the single-electron momentum density, the probability that an electron in a well-defined orbital has a given value of momentum. Over the last twenty years a technique has been developed for measuring momentum densities in atoms and molecules. The technique, ([ital e],2[ital e]) spectroscopy, is based on electron-impact ionization with complete determination of the momenta of both incoming and outgoing electrons. The conditions necessary to extract momentum-density information from the ionization experiments are examined and related to general theories of electron scattering. Different experimental arrangements are reviewed and momentum-density results from selected examples are discussed.
Wogonin inhibits inducible prostaglandin E 2 production in macrophages
Ichiro Wakabayashi; Kenichi Yasui
Effects of 5,7-dihydroxy-8-methoxyflavone (wogonin) on cyclooxygenase-2 (COX-2)-mediated prostaglandin E2 production in macrophages were investigated. Stimulation with lipopolysaccharide (LPS; 1 ?g\\/ml) greatly increased prostaglandin E2 production in RAW 264.7 murine macrophages. The stimulated prostaglandin E2 production was abolished in the presence of indomethacin (1 ?M) or cycloheximide (2 ?M), suggesting that the increased production of prostaglandin E2 by LPS reflects the
A novel anticancer agent, icaritin, induced cell growth inhibition, G1 arrest and mitochondrial transmembrane potential drop in human prostate carcinoma PC-3 cells.
Huang, Xin; Zhu, Danyan; Lou, Yijia
Icariin and icaritin with prenyl group have been demonstrated for their selective estrogen receptor modulating activities. We screened their effects on cell growth in human prostate carcinoma PC-3 cell line (estrogen receptor positive) in vitro. PC-3 cell line was used for the measurement of anti-carcinoma activities of 0-100 micromol/l icaritin and 30 micromol/l icariin. 1 micromol/l 17-beta estradiol (E(2)) served as the estrogen positive control, and 1 micromol/l ICI 182,780 [7 alpha-[9 (4,4,5,5,5-pentafluoropentyl) sulfinyl] nonyl]-estra-1,3,5(10)-triene-3,17h-diol
Association of Pur? and E2F-1 suppresses transcriptional activity of E2F-1
Nune Darbinian; Gary L Gallia; Mondira Kundu; Natalia Shcherbik; Anna Tretiakova; Antonio Giordano; Kamel Khalili
Protein-protein interaction can play an important role in the control of several biological events including gene transcription, replication and cell proliferation. E2F-1 is a DNA-binding transcription factor which, upon interaction with its target DNA sequence, induces expression of several S phase specific genes allowing progression of the cell cycle. Evidently, the activity of this protein is modulated by its cellular
Diabetes and exocrine pancreatic insufficiency in E2F1/E2F2 double-mutant mice
Iglesias, Ainhoa; Murga, Matilde; Laresgoiti, Usua; Skoudy, Anouchka; Bernales, Irantzu; Fullaondo, Asier; Moreno, Bernardino; Lloreta, José; Field, Seth J.; Real, Francisco X.; Zubiaga, Ana M.
E2F transcription factors are thought to be key regulators of cell growth control. Here we use mutant mouse strains to investigate the function of E2F1 and E2F2 in vivo. E2F1/E2F2 compound-mutant mice develop nonautoimmune insulin-deficient diabetes and exocrine pancreatic dysfunction characterized by endocrine and exocrine cell dysplasia, a reduction in the number and size of acini and islets, and their replacement by ductal structures and adipose tissue. Mutant pancreatic cells exhibit increased rates of DNA replication but also of apoptosis, resulting in severe pancreatic atrophy. The expression of genes involved in DNA replication and cell cycle control was upregulated in the E2F1/E2F2 compound-mutant pancreas, suggesting that their expression is repressed by E2F1/E2F2 activities and that the inappropriate cell cycle found in the mutant pancreas is likely the result of the deregulated expression of these genes. Interestingly, the expression of ductal cell and adipocyte differentiation marker genes was also upregulated, whereas expression of pancreatic cell marker genes were downregulated. These results suggest that E2F1/E2F2 activity negatively controls growth of mature pancreatic cells and is necessary for the maintenance of differentiated pancreatic phenotypes in the adult. PMID:15146237
New plant vectors for protein tagging with E2 epitope
Lenne Nigul; Allan Olspert; Merike Meier; Heiti Paves; Tiit Talpsep; Erkki Truve
E2Tag has been used for tagging of bacterial, yeast, and mammalian proteins. A set of plant expression vectors was constructed\\u000a for tagging proteins with E2Tag. Detection of E2-tagged proteins with specific antibodies inNicotiana benthamiana andNicotiana tabacum was easily done without any nonspecific background activity. No effect on the biological activity of the enzyme GUS, used\\u000a as a marker, was detected.
Emerging links between E2F control and mitochondrial function.
Benevolenskaya, Elizaveta V; Frolov, Maxim V
The family of E2F transcription factors is the key downstream target of the retinoblastoma tumor suppressor protein (pRB), which is frequently inactivated in human cancer. E2F is best known for its role in cell-cycle regulation and triggering apoptosis. However, E2F binds to thousands of genes and, thus, could directly influence a number of biologic processes. Given the plethora of potential E2F targets, the major challenge in the field is to identify specific processes in which E2F plays a functional role and the contexts in which a particular subset of E2F targets dictates a biologic outcome. Recent studies implicated E2F in regulation of expression of mitochondria-associated genes. The loss of such regulation results in severe mitochondrial defects. The consequences become evident during irradiation-induced apoptosis, where E2F-deficient cells are insensitive to cell death despite induction of canonical apoptotic genes. Thus, this novel function of E2F may have a major impact on cell viability, and it is independent of induction of apoptotic genes. Here, we discuss the implications of these findings in cancer biology. PMID:25634216
e2f translations (www.e2f.com) Rf. : Offre de stages 2013-04-17
Halazonetis, Thanos
stagiaires ŕ l'issue de leur stage. Offre de stages réservées ŕ des étudiants BAC + 4 minimum Stage de fin d'études Stage en alternance Année de césure aprčs le M1 Lieu du stage : Toulouse (Saint Orens) Stage rémunéré 4e2f translations (www.e2f.com) Réf. : Offre de stages 2013-04-17 OFFRE DE STAGE e2f translations
E2F6 in axial skeletal development and gliosis
Friesenhahn, Laurie Beth
E2F transcription factors were originally identified as regulators of cell cycle and cellular proliferation. In vivo mouse models have uncovered novel roles for these proteins in different developmental processes. This ...
Sibling rivalry in the E2F family.
Trimarchi, Jeffrey M; Lees, Jacqueline A
The E2F transcription factor family determines whether or not a cell will divide by controlling the expression of key cell-cycle regulators. The individual E2Fs can be divided into distinct subgroups that act in direct opposition to one another to promote either cellular proliferation or cell-cycle exit and terminal differentiation. What is the underlying molecular basis of this 'push-me-pull-you' regulation, and what are its biological consequences? PMID:11823794
Homeotic transformations of the axial skeleton that accompany a targeted deletion of E2f6
Jörg Storre; Hans-Peter Elsässer; Miriam Fuchs; Diana Ullmann; David M. Livingston; Stefan Gaubatz
E2F transcription factors play an important role in regulating mammalian cell proliferation. E2F6, the most recently identified E2F family member, is a transcriptional repressor. In an effort to ascertain the in vivo biological function of E2F6, we have generated an E2f6 mutant mouse strain. Mice lacking E2F6 are viable and healthy. Surprisingly, E2f6?\\/? embryonic fibroblasts proliferate normally. However, E2f6?\\/? animals
UHMWPE carrying estradiol to treat the particle-induced osteolysis-Processing and characterizing.
Liu, Aiqin; Qu, Shuxin; Chao, Mengmeng; Zhu, Minhao; Weng, Jie; Zhou, Zhongrong
The objective of this study was to explore the possibility of UHMWPE implant used as the drug carrier to treat particle-induced osteolysis. 17beta-estradiol (E2), which had the potential application on osteolysis treatment and the high melting point, was added into UHMWPE powder to produce UHMWPE-E2 composites through hot press processing. The hydrophobicity, crystallinity, mechanical properties, and wear performance of the UHMWPE-E2 were characterized compared with the control UHMWPE. The thermal analysis and Fourier Transform Infrared Spectroscopy results demonstrated that the hot press processing would not alter the functional groups of E2 in this study. There were no significant differences in the hydrophobicity and crystallinity between the UHMWPE-E2 and UHMWPE. The UHMWPE-E2 showed satisfying mechanical properties, including ultimate tensile strength (47.2 +/- 3.6 MPa), yield strength (25.0 +/- 0.6 MPa) and elongation at break (320 +/- 25.5 %), which were similar with the control UHMWPE. The friction coefficients and worn scars were similar between the UHMWPE-E2 and the control UHMWPE. The wear mechanism of the UHMWPE-E2 and UHMWPE both were abrasive wear under dry friction. The UHMWPE-E2 possesses the approving mechanical properties and wear performance compared with the control UHMWPE, which might be used as the potential implanted drug carrier to prevent the particle-induced osteolysis in joint replacements. PMID:18563828
Large Scale Genotype Comparison of Human Papillomavirus E2-Host Interaction Networks Provides New Insights for E2 Molecular Functions
Muller, Mandy; Jacob, Yves; Jones, Louis; Weiss, Amélie; Brino, Laurent; Chantier, Thibault; Lotteau, Vincent; Favre, Michel; Demeret, Caroline
Human Papillomaviruses (HPV) cause widespread infections in humans, resulting in latent infections or diseases ranging from benign hyperplasia to cancers. HPV-induced pathologies result from complex interplays between viral proteins and the host proteome. Given the major public health concern due to HPV-associated cancers, most studies have focused on the early proteins expressed by HPV genotypes with high oncogenic potential (designated high-risk HPV or HR-HPV). To advance the global understanding of HPV pathogenesis, we mapped the virus/host interaction networks of the E2 regulatory protein from 12 genotypes representative of the range of HPV pathogenicity. Large-scale identification of E2-interaction partners was performed by yeast two-hybrid screenings of a HaCaT cDNA library. Based on a high-confidence scoring scheme, a subset of these partners was then validated for pair-wise interaction in mammalian cells with the whole range of the 12 E2 proteins, allowing a comparative interaction analysis. Hierarchical clustering of E2-host interaction profiles mostly recapitulated HPV phylogeny and provides clues to the involvement of E2 in HPV infection. A set of cellular proteins could thus be identified discriminating, among the mucosal HPV, E2 proteins of HR-HPV 16 or 18 from the non-oncogenic genital HPV. The study of the interaction networks revealed a preferential hijacking of highly connected cellular proteins and the targeting of several functional families. These include transcription regulation, regulation of apoptosis, RNA processing, ubiquitination and intracellular trafficking. The present work provides an overview of E2 biological functions across multiple HPV genotypes. PMID:22761572
Hepatitis C Virus E2 Envelope Glycoprotein Core Structure
Kong, Leopold [The Scripps Research Inst., La Jolla, CA (United States); Giang, Erick [The Scripps Research Inst., La Jolla, CA (United States); Nieusma, Travis [The Scripps Research Inst., La Jolla, CA (United States); Kadam, Rameshwar U. [The Scripps Research Inst., La Jolla, CA (United States); Cogburn, Kristin E. [The Scripps Research Inst., La Jolla, CA (United States); Hua, Yuanzi [The Scripps Research Inst., La Jolla, CA (United States); Dai, Xiaoping [The Scripps Research Inst., La Jolla, CA (United States); Stanfield, Robyn L. [The Scripps Research Inst., La Jolla, CA (United States); Burton, Dennis R. [The Scripps Research Inst., La Jolla, CA (United States); Ward, Andrew B. [The Scripps Research Inst., La Jolla, CA (United States); Wilson, Ian A. [The Scripps Research Inst., La Jolla, CA (United States); Law, Mansun [The Scripps Research Inst., La Jolla, CA (United States)
Hepatitis C virus (HCV), a Hepacivirus, is a major cause of viral hepatitis, liver cirrhosis, and hepatocellular carcinoma. HCV envelope glycoproteins E1 and E2 mediate fusion and entry into host cells and are the primary targets of the humoral immune response. The crystal structure of the E2 core bound to broadly neutralizing antibody AR3C at 2.65 angstroms reveals a compact architecture composed of a central immunoglobulin-fold ? sandwich flanked by two additional protein layers. The CD81 receptor binding site was identified by electron microscopy and site-directed mutagenesis and overlaps with the AR3C epitope. The x-ray and electron microscopy E2 structures differ markedly from predictions of an extended, three-domain, class II fusion protein fold and therefore provide valuable information for HCV drug and vaccine design.
Hepatitis C virus E2 envelope glycoprotein core structure.
Kong, Leopold; Giang, Erick; Nieusma, Travis; Kadam, Rameshwar U; Cogburn, Kristin E; Hua, Yuanzi; Dai, Xiaoping; Stanfield, Robyn L; Burton, Dennis R; Ward, Andrew B; Wilson, Ian A; Law, Mansun
Hepatitis C virus (HCV), a Hepacivirus, is a major cause of viral hepatitis, liver cirrhosis, and hepatocellular carcinoma. HCV envelope glycoproteins E1 and E2 mediate fusion and entry into host cells and are the primary targets of the humoral immune response. The crystal structure of the E2 core bound to broadly neutralizing antibody AR3C at 2.65 angstroms reveals a compact architecture composed of a central immunoglobulin-fold ? sandwich flanked by two additional protein layers. The CD81 receptor binding site was identified by electron microscopy and site-directed mutagenesis and overlaps with the AR3C epitope. The x-ray and electron microscopy E2 structures differ markedly from predictions of an extended, three-domain, class II fusion protein fold and therefore provide valuable information for HCV drug and vaccine design. PMID:24288331
Hepatitis C virus E2 envelope glycoprotein core structure
Kong, Leopold; Giang, Erick; Nieusma, Travis; Kadam, Rameshwar U.; Cogburn, Kristin E.; Hua, Yuanzi; Dai, Xiaoping; Stanfield, Robyn L.; Burton, Dennis R.; Ward, Andrew B.; Wilson, Ian A.; Law, Mansun
Hepatitis C virus (HCV), a Hepacivirus, is a major cause of viral hepatitis, liver cirrhosis and hepatocellular carcinoma. HCV envelope glycoproteins E1 and E2 mediate fusion and entry into host cells and are the primary targets of the humoral immune response. The crystal structure of the E2 core bound to broadly neutralizing antibody AR3C at 2.65 Ĺ reveals a compact architecture composed of a central Ig-fold ?-sandwich flanked by two additional protein layers. The CD81 receptor-binding site was identified by EM and by site-directed mutagenesis and overlaps with the AR3C epitope. The x-ray and EM E2 structures differ markedly from predictions of an extended, three-domain, class II fusion protein fold and therefore provide invaluable information for HCV drug and vaccine design. PMID:24288331
Impaired secretion of apolipoprotein E2 from macrophages.
Fan, Daping; Qiu, Shenfeng; Overton, Cheryl D; Yancey, Patricia G; Swift, Larry L; Jerome, W Gray; Linton, Macrae F; Fazio, Sergio
Human apoE is a multifunctional and polymorphic protein synthesized and secreted by liver, brain, and tissue macrophages. Here we show that apoE isoforms and mutants expressed through lentiviral transduction display cell-specific differences in secretion efficiency. Whereas apoE3, apoE4, and a natural mutant of apoE4 (apoE-Cys(142)) were efficiently secreted from macrophages, apoE2 and a non-natural apoE mutant (apoE-Cys(112)/Cys(142)) were retained in the perinuclear region and only minimally secreted. The secretory block for apoE2 in macrophages was not affected by the ablation of LDLR (low density lipoprotein receptor), ABCA-1, or SR-BI (scavenger receptor class B type I) but was released in the absence of low density lipoprotein receptor related protein (LRP). In co-immunoprecipitation experiments, an anti-apoE antibody pulled down two times more LRP in apoE2-transduced macrophages than in apoE3-expressing macrophages. Non-reducing SDS-PAGE/Western blot analyses showed that macrophage apoE2 is mostly dimeric and multimeric, whereas apoE3 is predominantly monomeric. ApoE2 retention and multimer formation also occurred in human macrophages derived from the monocyte cell line THP-1. These results were specific for macrophages, as in transduced mouse primary hepatocytes: 1) ApoE2 was secreted as efficiently as apoE3 and apoE4; 2) all isoforms were exclusively in monomeric form; 3) there was no co-immunoprecipitation of apoE and LRP. A microsomal triglyceride transfer protein (MTP) inhibitor nearly deleted apoB100 secretion from hepatocytes without affecting apoE secretion. These data show that macrophages retain apoE2, a highly expressed protein carried by about 8% of the human population. Given the role of locally produced apoE in regulating cholesterol efflux, modulating inflammation, and controlling oxidative stress, this unique property of apoE2 may have important impacts on atherogenesis. PMID:17341585
Random phage mimotopes recognized by monoclonal antibodies against the pyruvate dehydrogenase complex-E2 (PDC-E2).
Cha, S; Leung, P S; Van de Water, J; Tsuneyama, K; Joplin, R E; Ansari, A A; Nakanuma, Y; Schatz, P J; Cwirla, S; Fabris, L E; Neuberger, J M; Gershwin, M E; Coppel, R L
Dihydrolipoamide acetyltransferase, the E2 component of the pyruvate dehydrogenase complex (PDC-E2), is the autoantigen most commonly recognized by autoantibodies in primary biliary cirrhosis (PBC). We identified a peptide mimotope(s) of PDC-E2 by screening a phage-epitope library expressing random dodecapeptides in the pIII coat protein of fd phage using C355.1, a murine monoclonal antibody (mAb) that recognizes a conformation-dependent epitope in the inner lipoyl domain of PDC-E2 and uniquely stains the apical region of bile duct epithelium (BDE) only in patients with PBC. Eight different sequences were identified in 36 phage clones. WMSYPDRTLRTS was present in 29 clones; WESYPFRVGTSL, APKTYVSVSGMV, LTYVSLQGRQGH, LDYVPLKHRHRH, AALWGVKVRHVS, KVLNRIMAGVRH and GNVALVSSRVNA were singly represented. Three common amino acid motifs (W-SYP, TYVS, and VRH) were shared among all peptide sequences. Competitive inhibition of the immunohistochemical staining of PBC BDE was performed by incubating the peptides WMSYPDRTLRTS, WESYPDRTLRTS, APKTYVSVSGMV, and AALWGVKVRHVS with either C355.1 or a second PDC-E2-specific mAb, C150.1. Both mAbs were originally generated to PDC-E2 but map to distinct regions of PDC-E2. Two of the peptides, although selected by reaction with C355.1, strongly inhibited the staining of BDE by C150.1, whereas the peptide APKTYVSVSGMV consistently inhibited the staining of C355.1 on biliary duct epithelium more strongly than the typical mitochondrial staining of hepatocytes. Rabbit sera raised against the peptide WMSYPDRTLRTS stained BDE of livers and isolated bile duct epithelial cells of PBC patients more intensively than controls. The rabbit sera stained all size ducts in normals, but only small/medium-sized ductules in PBC livers. These studies provide evidence that the antigen present in BDE is a molecular mimic of PDC-E2, and not PDC-E2 itself. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8855289
Estrogen Levels in House Wren (Troglodytes aedon) Egg Yolks
V. BrookWaggoner
Estrogen, when present in early embryonic development, regulates sexual differentiation in the avian nestling and adult. In this study, I developed a procedure to extract and quantify levels (by radioimmunoassay) of the estrogen, 17[beta]-estradiol, in house wren (Troglodytes aedon) egg yolk. Levels of 17[beta]-estradiol found in one clutch of eggs increased with the order of laying, indicating female house wrens
Imperial College London EEE 1L1 Autumn 2009 E2.2 Analogue Electronics E2.2 Analogue Electronics
Papavassiliou, Christos
Imperial College London EEE 1L1 Autumn 2009 E2.2 Analogue Electronics E2.2 Analogue Electronics Autumn 2009 E2.2 Analogue Electronics What analogue electronics is · Engineering, i.e. the analysis EEE 3L1 Autumn 2009 E2.2 Analogue Electronics analogue electronics is not only · CMOS integrated
Low-energy behavior of $E2$ strength functions
R. Schwengner
Electric quadrupole strength functions have been deduced from averages of a large number of $E2$ transition strengths calculated within the shell model for the nuclides $^{94}$Mo and $^{95}$Mo. These strength functions are at variance with phenomenological approximations as provided by the Reference Input Parameter Library RIPL-3 for calculations of reaction rates on the basis of the statistical model.
E-2C Loads Calibration in DFRC Flight Loads Lab
NASA Technical Reports Server (NTRS)
Schuster, Lawrence S.
Objectives: a) Safely and efficiently perform structural load tests on NAVAIR E-2C aircraft to calibrate strain gage instrumentation installed by NAVAIR; b) Collect load test data and derive loads equations for use in NAVAIR flight tests; and c) Assist flight test team with use of loads equations measurements at PAX River.
US Army Corps of Engineers public web site for the "Environmental Effects of Dredging and Disposal" ("E2-D2") searchable database of published reports and studies about environmental impacts associated with dredging and disposal operations. Many of the reports and studies are ava...
Ameliorative effects of Anoectochilus formosanus extract on osteopenia in ovariectomized rats.
Shih, C C; Wu, Y W; Lin, W C
The purpose of this study was to determine ameliorative effects of crude aqueous extract of Anoectochilus formosanus (AFE) on osteopenia in ovariectomized (OVX) rats. First, all of the rats were divided into sham and OVX groups. The OVX rats were allowed to lose bone for 6 weeks. At 6 weeks post-OVX, the OVX rats were divided into four groups treated with water, 17beta-estradiol (30 microg/kg, daily s.c. injection) or AFE (0.5, 2 g/kg, daily, orally) for 12 weeks. In OVX rats, the increases of body weight and serum total cholesterol were significantly decreased by AFE or 17beta-estradiol treatment. In OVX rats, atrophy of uterus and vagina was preserved by treatment with 17beta-estradiol, but not by AFE. The decreased weight of pituitary was increased by treatment with both 17beta-estradiol and AFE. There were decreases in bone density and calcium content including the right femur and the fourth lumbar vertebra, when compared with the sham control rats. Treatment with either 17beta-estradiol or AFE ameliorated these changes induced by OVX. In addition, ovariectomy increased serum alkaline phosphatase levels. The increases were suppressed by the treatment with 17beta-estradiol and AFE. Our results demonstrated that AEF could ameliorate ovariectomy-induced osteopenia. PMID:11535369
The effect of estrogen synthesis inhibition on hippocampal memory.
Bayer, Janine; Rune, Gabriele; Schultz, Heidrun; Tobia, Michael J; Mebes, Imke; Katzler, Olaf; Sommer, Tobias
17-Beta-estradiol (E2) facilitates long term-potentiation (LTP) and increases spine synapse density in hippocampal neurons of ovariectomized rodents. Consistent with these beneficial effects on the cellular level, E2 improves hippocampus-dependent memory. A prominent approach to study E2 effects in rodents is the inhibition of its synthesis by letrozole, which reduces LTPs and spine synapse density. In the current longitudinal functional magnetic resonance imaging (fMRI) study, we translated this approach to humans and compared the impact of E2 synthesis inhibition on memory performance and hippocampal activity in post-menopausal women taking letrozole (n=21) to controls (n=24). In particular, we employed various behavioral memory paradigms that allow the disentanglement of hippocampus-dependent and -independent memory. Consistent with the literature on rodents, E2 synthesis inhibition specifically impaired hippocampus-dependent memory, however, this did not apply to the same degree to all of the employed paradigms. On the neuronal level, E2 depletion tended to decrease hippocampal activity during encoding, whereas it increased activity in the anterior cingulate and the dorsolateral prefrontal cortex. We thus infer that the inhibition of E2 synthesis specifically impairs hippocampal functioning in humans, whereas the increased prefrontal activity presumably reflects a compensatory mechanism, which is already known from studies on cognitive aging and Alzheimer's disease. PMID:25863445
Estradiol uptake, toxicity, metabolism, and adverse effects on cadmium-treated amphibian embryos.
Fridman, Osvaldo; Corró, Lucrecia; Herkovits, Jorge
The exposure of Bufo arenarum embryos to 25 micromol/L 17beta-estradiol (E2) resulted in 100% lethality within 48 hr, whereas 10 micromol//L E2 was the no observed effect concentration value for short-term chronic (7 days) exposure. The toxicity profile curves show that lethal effects were proportional to the E2 concentration and the time of exposure. The E2 uptake resulted in 20.1 ng E2/mg embryo at 8 hr posttreatment, but 67.3% of this value was achieved during the first 30 min of incubation with this estrogen. Regarding metabolism, the embryos synthesize estrone (E1) from E2 by means of 17beta-hydroxysteroid dehydrogenase. Simultaneous treatments of Bufo arenarum embryos with 1 mg/L Cd2+ and 0.1, 1, or 10 micromol/L E2 enhanced the lethality exerted by cadmium in 76.7, 80, and 83.3% of embryos, respectively. The results indicate that estrogenic endocrine disruptors could have an adverse effect on amphibian embryos and enhance the toxic effect of Cd on amphibian embryos. This study points to the possibility of using the AMPHITOX test as a screening method for potential endocrine disruption as well as the combined effects of chemical mixtures. PMID:15175173
E2-transition probabilities for NiXVIII
NASA Astrophysics Data System (ADS)
Ray, Hasi
Accurate theoretical data for the transition probabilities are highly demanding in astrophysics and in the study of plasma in astrophysical objects and fusion devices. Na-like highly stripped ions of iron group, specially NiXVIII is very important in this respect. A highly improved basis in a relativistic many-body coupled-cluster method (CCM) to include correlation properly is employed to calculate excitation energies, the electric quadrupole (E2) transition line strengths and transition probabilities for NiXVIII. The effect of correlation is studied thoroughly. The present improved data for different atomic/ionic properties are compared with the available theoretical and/or experimental data and they are in agreement. Some E2 transition data are reported for the first time.
Formulation of Ames 24E2 IR-black coating
NASA Technical Reports Server (NTRS)
Smith, Sheldon M.
The formulation of Ames 24E2 IR-black coating and a rationale for the selection of its components are given. The objective was to make a very rough, very thick, and highly absorbing coating to attenuate the specular reflectance of telescope baffles at far-IR wavelengths. Application and curing instructions are also given. Outgassing measurements are quite low following a 24-hour radiative cure.
Generalized seniority and E 2 transitions in the tin isotopes
NASA Astrophysics Data System (ADS)
Morales, Irving O.; Van Isacker, P.; Talmi, I.
Recently, a shallow minimum was discovered in B(E2) values in even Sn isotopes around the middle of the neutron major shell. A peak in that region was expected according to calculations using generalized seniority. In a model calculation we show that the observed shape is consistent with generalized seniority. It seems to be due to the order of filling of j-orbits.
Advanced Stirling Convertor (ASC-E2) Characterization Testing
NASA Technical Reports Server (NTRS)
Williams, Zachary D.; Oriti, Salvatore M.
Testing has been conducted on Advanced Stirling Convertor (ASC-E2) convertors at NASA Glenn Research Center in support of the Advanced Stirling Radioisotope Generator (ASRG) Project. This testing has been conducted to understand sensitivities of convertor parameters due to environmental and operational changes during operation of the ASRG in missions to space. This paper summarizes test results and explains in terms of operation of the ASRG during space missions.
Advanced Stirling Convertor (ASC-E2) Characterization Testing
NASA Technical Reports Server (NTRS)
Williams, Zachary D.; Oriti, Salvatore M.
Testing has been conducted on Advanced Stirling Convertors (ASCs)-E2 at NASA Glenn Research Center in support of the Advanced Stirling Radioisotope Generator (ASRG) project. This testing has been conducted to understand sensitivities of convertor parameters due to environmental and operational changes during operation of the ASRG in missions to space. This paper summarizes test results and explains the operation of the ASRG during space missions
Multicilin drives centriole biogenesis via E2f proteins.
Ma, Lina; Quigley, Ian; Omran, Heymut; Kintner, Chris
Multiciliate cells employ hundreds of motile cilia to produce fluid flow, which they nucleate and extend by first assembling hundreds of centrioles. In most cells, entry into the cell cycle allows centrioles to undergo a single round of duplication, but in differentiating multiciliate cells, massive centriole assembly occurs in G0 by a process initiated by a small coiled-coil protein, Multicilin. Here we show that Multicilin acts by forming a ternary complex with E2f4 or E2f5 and Dp1 that binds and activates most of the genes required for centriole biogenesis, while other cell cycle genes remain off. This complex also promotes the deuterosome pathway of centriole biogenesis by activating the expression of deup1 but not its paralog, cep63. Finally, we show that this complex is disabled by mutations in human Multicilin that cause a severe congenital mucociliary clearance disorder due to reduced generation of multiple cilia. By coopting the E2f regulation of cell cycle genes, Multicilin drives massive centriole assembly in epithelial progenitors in a manner required for multiciliate cell differentiation. PMID:24934224
Multicilin drives centriole biogenesis via E2f proteins
Ma, Lina; Quigley, Ian; Omran, Heymut; Kintner, Chris
Multiciliate cells employ hundreds of motile cilia to produce fluid flow, which they nucleate and extend by first assembling hundreds of centrioles. In most cells, entry into the cell cycle allows centrioles to undergo a single round of duplication, but in differentiating multiciliate cells, massive centriole assembly occurs in G0 by a process initiated by a small coiled-coil protein, Multicilin. Here we show that Multicilin acts by forming a ternary complex with E2f4 or E2f5 and Dp1 that binds and activates most of the genes required for centriole biogenesis, while other cell cycle genes remain off. This complex also promotes the deuterosome pathway of centriole biogenesis by activating the expression of deup1 but not its paralog, cep63. Finally, we show that this complex is disabled by mutations in human Multicilin that cause a severe congenital mucociliary clearance disorder due to reduced generation of multiple cilia. By coopting the E2f regulation of cell cycle genes, Multicilin drives massive centriole assembly in epithelial progenitors in a manner required for multiciliate cell differentiation. PMID:24934224
Estradiol affects liver mitochondrial function in ovariectomized and tamoxifen-treated ovariectomized female rats
Moreira, Paula I. [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Physiology, Faculty of Medicine, University of Coimbra, 3005-504 Coimbra (Portugal); Custodio, Jose B.A. [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3005-504 Coimbra (Portugal); Nunes, Elsa [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Physiology, Faculty of Medicine, University of Coimbra, 3005-504 Coimbra (Portugal); Moreno, Antonio [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Department of Zoology, Faculty of Sciences and Technology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Marine Research, University of Coimbra, 3005-504 Coimbra (Portugal); Seica, Raquel [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Physiology, Faculty of Medicine, University of Coimbra, 3005-504 Coimbra (Portugal); Oliveira, Catarina R. [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Biochemistry, Faculty of Medicine, University of Coimbra, 3005-504 Coimbra (Portugal); Santos, Maria S. [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal) and Department of Zoology, Faculty of Sciences and Technology, University of Coimbra, 3005-504 Coimbra (Portugal)]. E-mail: firstname.lastname@example.com
Given the tremendous importance of mitochondria to basic cellular functions as well as the critical role of mitochondrial impairment in a vast number of disorders, a compelling question is whether 17{beta}-estradiol (E2) modulates mitochondrial function. To answer this question we exposed isolated liver mitochondria to E2. Three groups of rat females were used: control, ovariectomized and ovariectomized treated with tamoxifen. Tamoxifen has antiestrogenic effects in the breast tissue and is the standard endocrine treatment for women with breast cancer. However, under certain circumstances and in certain tissues, tamoxifen can also exert estrogenic agonist properties. We observed that at basal conditions, ovariectomy and tamoxifen treatment do not induce any statistical alteration in oxidative phosphorylation system and respiratory chain parameters. Furthermore, tamoxifen treatment increases the capacity of mitochondria to accumulate Ca{sup 2+} delaying the opening of the permeability transition pore. The presence of 25 {mu}M E2 impairs respiration and oxidative phosphorylation system these effects being similar in all groups of animals studied. Curiously, E2 protects against lipid peroxidation and increases the production of H{sub 2}O{sub 2} in energized mitochondria of control females. Our results indicate that E2 has in general deleterious effects that lead to mitochondrial impairment. Since mitochondrial dysfunction is a triggering event of cell degeneration and death, the use of exogenous E2 must be carefully considered.
E2F1 and E2F2 induction in response to DNA damage preserves genomic stability in neuronal cells.
Castillo, Daniela S; Campalans, Anna; Belluscio, Laura M; Carcagno, Abel L; Radicella, J Pablo; Cánepa, Eduardo T; Pregi, Nicolás
E2F transcription factors regulate a wide range of biological processes, including the cellular response to DNA damage. In the present study, we examined whether E2F family members are transcriptionally induced following treatment with several genotoxic agents, and have a role on the cell DNA damage response. We show a novel mechanism, conserved among diverse species, in which E2F1 and E2F2, the latter specifically in neuronal cells, are transcriptionally induced after DNA damage. This upregulation leads to increased E2F1 and E2F2 protein levels as a consequence of de novo protein synthesis. Ectopic expression of these E2Fs in neuronal cells reduces the level of DNA damage following genotoxic treatment, while ablation of E2F1 and E2F2 leads to the accumulation of DNA lesions and increased apoptotic response. Cell viability and DNA repair capability in response to DNA damage induction are also reduced by the E2F1 and E2F2 deficiencies. Finally, E2F1 and E2F2 accumulate at sites of oxidative and UV-induced DNA damage, and interact with ?H2AX DNA repair factor. As previously reported for E2F1, E2F2 promotes Rad51 foci formation, interacts with GCN5 acetyltransferase and induces histone acetylation following genotoxic insult. The results presented here unveil a new mechanism involving E2F1 and E2F2 in the maintenance of genomic stability in response to DNA damage in neuronal cells. PMID:25892555
E2F7 and E2F8 promote angiogenesis through transcriptional activation of VEGFA in cooperation with HIF1
Weijts, Bart G M W; Bakker, Walbert J; Cornelissen, Peter W A; Liang, Kuo-Hsuan; Schaftenaar, Frank H; Westendorp, Bart; de Wolf, Charlotte A C M T; Paciejewska, Maya; Scheele, Colinda L G J; Kent, Lindsey; Leone, Gustavo; Schulte-Merker, Stefan; de Bruin, Alain
The E2F family of transcription factors plays an important role in controlling cell-cycle progression. While this is their best-known function, we report here novel functions for the newest members of the E2F family, E2F7 and E2F8 (E2F7/8). We show that simultaneous deletion of E2F7/8 in zebrafish and mice leads to severe vascular defects during embryonic development. Using a panel of transgenic zebrafish with fluorescent-labelled blood vessels, we demonstrate that E2F7/8 are essential for proper formation of blood vessels. Despite their classification as transcriptional repressors, we provide evidence for a molecular mechanism through which E2F7/8 activate the transcription of the vascular endothelial growth factor A (VEGFA), a key factor in guiding angiogenesis. We show that E2F7/8 directly bind and stimulate the VEGFA promoter independent of canonical E2F binding elements. Instead, E2F7/8 form a transcriptional complex with the hypoxia inducible factor 1 (HIF1) to stimulate VEGFA promoter activity. These results uncover an unexpected link between E2F7/8 and the HIF1-VEGFA pathway providing a molecular mechanism by which E2F7/8 control angiogenesis. PMID:22903062
The First Human Epitope Map of the Alphaviral E1 and E2 Proteins Reveals a New E2 Epitope with Significant Virus Neutralizing Activity
Ann R. Hunt; Shana Frederickson; Toshiaki Maruyama; John T. Roehrig; Carol D. Blair
BackgroundVenezuelan equine encephalitis virus (VEEV) is responsible for VEE epidemics that occur in South and Central America and the U.S. The VEEV envelope contains two glycoproteins E1 (mediates cell membrane fusion) and E2 (binds receptor and elicits virus neutralizing antibodies). Previously we constructed E1 and E2 epitope maps using murine monoclonal antibodies (mMAbs). Six E2 epitopes (E2c,d,e,f,g,h) bound VEEV-neutralizing antibody
Astro-E2 Magnesium Diboride High Current Leads
NASA Technical Reports Server (NTRS)
Panek, J. S.; Tuttle, J. G.; Riall, S.; Mustafi, S.; Gray, A.; Edmonds, R.; Marrero, V.
The recent discovery of superconducting properties in MgB_2 and rapid development of small diameter steel-clad wires has opened up the possibility of enhancing the design of the baseline Astro-E2 high current lead assembly. Replacing YBCO filaments with MgB_2 wires and modifying the heat sink location can give much higher margins against quench from temperature oscillations of the 4 K heat sink, although wih some overall thermal penalty. The design and performance of a new lead assembly during flight qualification is discussed, with emphasis on thermal, structural, and electrical test results.
Astro-E2 Magnesium Diboride High Current Leads
Panek, J.S.; Tuttle, J.G.; Marrero, V.; Mustafi, S.; Edmonds, R.; Gray, A.; Riall, S. [Cryogenics and Fluids Branch/Code 552, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
The recent discovery of superconducting properties in MgB2 and rapid development of small diameter steel-clad wires has opened up the possibility of enhancing the design of the baseline Astro-E2 high current lead assembly. Replacing YBCO filaments with MgB2 wires and modifying the heat sink location can give much higher margins against quench from temperature oscillations of the 4 K heat sink, although with some overall thermal penalty. The design and performance of a new lead assembly during flight qualification is discussed, with emphasis on thermal, structural, and electrical test results.
Scattering properties of the 2 e-2 e+ polyelectronic system
NASA Astrophysics Data System (ADS)
Daily, K. M.; von Stecher, Javier; Greene, Chris H.
We study the 2 e-2 e+ equal-mass charge-neutral four-body system in the adiabatic hyperspherical framework. The lowest few adiabatic potentials are calculated for zero orbital angular momentum, positive parity, and charge conjugation symmetries. Propagating the R matrix, the low-energy s -wave scattering lengths of the singlet-singlet and triplet-triplet spin configurations are calculated. Last, we calculate the S matrix for energies above the ionic threshold to estimate the transition rates between the single ionic fragmentation channel and the lowest few dimer-dimer fragmentation channels.
Reduced Probabilities of E2-Transitions in {sup 174}Yb
Okhunov, A. A. [Quantum Science Center Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Institute for Nuclear Physics, Academy Science of Uzbekistan, 100214 Tashkent (Uzbekistan); Kassim, Hasan Abu [Quantum Science Center Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)
This paper describes the ground (gr) and exited states of even-even deformed nuclei with a phenomenological model, which takes into account the mixing of gr states, 0{sub n}{sup +}({beta}{sub n})-, 2{sub n}{sup +}({gamma}{sub n})- and {Kappa}{sup {pi}} 1{sub n}{sup +}- rotational bands. The calculation has been done for the isotope Yb. The energy spectra are found to be consistent with the energies from experimental data. The reduced probabilities of the electric quadrupole E2-transitions from {beta}{sub n} and {gamma}{sub n} band states are calculated and agree quite well with the experimental values.
Effects of aromatase inhibitors on in vitro steroidogenesis by Atlantic salmon (Salmo salar) gonadal and brain tissue.
Lee, Peter S; Pankhurst, Ned W; King, Henry R
In order to assess the efficacy of selected aromatase inhibitors on Atlantic salmon (Salmo salar) ovarian and brain tissue, in vitro systems were developed for measuring 17beta-estradiol (E(2)) production by these tissues. Isolated vitellogenic follicles, or homogenised whole brains were incubated at 10 degrees C in complete Cortlands solution for 18 or 42 h respectively, and E(2) levels in the medium were determined by RIA. The addition of testosterone to the medium increased E(2) production in all preparations. E(2) production by whole brain homogenate was reduced by co-incubation with the aromatase inhibitors 1,4,6-androstatriene-3,17-dione (ATD), 4-androstene-4-ol-3,17-dione (OHA), aminoglutethimide, fadrozole or miconazole. Fadrozole, ATD, and OHA reduced E(2) production by vitellogenic follicles at a medium concentration of 0.1 microg mL(-1), whereas miconazole was only effective at 10 microg mL(-1). This study demonstrates a simple and rapid screening method for assessing the efficacy of aromatase inhibitors on fish tissues, and that the aromatase inhibitors ATD, OHA and fadrozole are potent inhibitors of both brain and gonadal aromatase in vitro, in Atlantic salmon. PMID:16870481
RWD Domain as an E2 (Ubc9)-Interaction Module.
Alontaga, Aileen Y; Ambaye, Nigus D; Li, Yi-Jia; Vega, Ramir; Chen, Chih-Hong; Bzymek, Krzysztof P; Williams, John C; Hu, Weidong; Chen, Yuan
An RWD domain is a well conserved domain found through bioinformatic analysis of the human proteome sequence; however, its function has been unknown. Ubiquitin-like modifications require the catalysis of three enzymes generally known as E1, E2, and E3. We solved the crystal structure of the E2 for the small ubiquitin-like modifiers (SUMO) in complex with an RWD domain and confirmed the structure using solution NMR analysis. The binding surface of RWD on Ubc9 is located near the N terminus of Ubc9 that is known to be involved in noncovalent binding of the proteins in the conjugation machinery, including a domain of E1, SUMO, and an E3 ligase. NMR data indicate that the RWD domain does not bind to SUMO and E1. The interaction between RWD and Ubc9 has a Kd of 32 ± 4 ?m. Consistent with the structure and binding affinity and in contrast to a previous report, the RWD domain and RWDD3 have minimal effects on global SUMOylation. The structural and biochemical information presented here forms the basis for further investigation of the functions of RWD-containing proteins. PMID:25918163
Selective hydrogenation of ( E)-2-hexenal to ( E)-2-hexen-1-ol over Co-based bimetallic catalysts
Chie Ando; Aya Ikumoto; Hideki Kurokawa; Kazuo Sugiyama; Hiroshi Miura
Hydrogenation of (E)-2-hexenal was carried out in a liquid phase using Co-based bimetallic catalysts (M–Co\\/Al2O3, M=Pd, Pt, Ru, Rh, Sn, Fe, or Cu). Pd–Co\\/Al2O3 showed the highest activity among the catalysts tested and catalyzed the hydrogenation of C?C bond predominantly to produce hexanal and 1-hexanol. Pt–Co\\/Al2O3 was more active than monometallic Co\\/Al2O3 for the hydrogenation of C?O bond. The excellent
Direct coating of culture medium from cells secreting classical swine fever virus E2 antigen on ELISA plates for detection of E2-specific antibodies.
Cheng, Ta-Chun; Pan, Chu-Hsiang; Chen, Chien-Shu; Chuang, Kuo-Hsiang; Chuang, Chih-Hung; Huang, Chien-Chaio; Chu, Yu-Yi; Yang, Ya-Chun; Chu, Pei-Yu; Kao, Chien-Han; Hsieh, Yuan-Chin; Cheng, Tian-Lu
The envelope glycoprotein E2 of classical swine fever virus (CSFV) is widely used as a marker for measuring vaccine efficacy and antibody titer. The glycosylation profile of E2 may affect the immunogenicity of the vaccine and the timing of re-vaccination. In this study, a human embryonic kidney cell line was used to secrete fully-glycosylated CSFV E2, which was then coated onto ELISA plates without purification or adjustment. The resulting E2-secreting medium-direct-coating (E2-mDc) ELISA was successfully used to measure anti-E2 antibody titers in vaccinated and field pig sera samples. Compared with a virus neutralization test (as standard), the E2-mDc ELISA was found to be more accurate (90%) than a commercial CSFV antibody diagnostic kit (62%). In conclusion, the mammalian cell-secreted antigen can provide cheap, accurate and effective assays for vaccine efficacy and disease diagnoses. PMID:25975854
HIF proteins connect the RB-E2F factors to angiogenesis
Bakker, Walbert. J.; Weijts, Bart G.M.W.; Westendorp, Bart; de Bruin, Alain
Recently, we showed that E2F7 and E2F8 (E2F7/8) are critical regulators of angiogenesis through transcriptional control of VEGFA in cooperation with HIF.1 Here we investigate the existence of other novel putative angiogenic E2F7/8-HIF targets, and discuss the role of the RB-E2F pathway in regulating angiogenesis during embryonic and tumor development. PMID:23412359
Evaluation of Emerging Contaminants of Concern at the South District Wastewater Treatment Plant Based on Seasonal Events, Miami-Dade County, Florida, 2004
Lietz, Arthur C.; Meyer, Michael T.
The Comprehensive Everglades Restoration Plan has identified highly treated wastewater as a possible water source for the restoration of natural water flows and hydroperiods in selected coastal areas, including the Biscayne Bay coastal wetlands. One potential source of reclaimed wastewater for the Biscayne Bay coastal wetlands is the effluent from the South District Wastewater Treatment Plant in southern Miami-Dade County. The U.S. Geological Survey, in cooperation with the Comprehensive Everglades Restoration Plan Wastewater Reuse Technology Pilot Project Delivery Team, initiated a study to assess the presence of emerging contaminants of concern in the South District Wastewater Treatment Plant influent and effluent using current wastewater-treatment methods. As part of the study, 24-hour composite and discrete samples were collected at six locations (influent at plants 1 and 2, effluent pump, reuse train, chlorine dioxide unit, and ultraviolet pilot unit) at the plant during: (1) a dry-season, low-flow event on March 2-3, 2004, with an average inflow rate of 83.7 million gallons per day; (2) a wet-season, average-flow event on July 20-21, 2004, with an average inflow rate of 89.7 million gallons per day; and (3) high-rate disinfection tests on October 5 and 20, 2004, with average flow rates of 84.1 and 119.6 million gallons per day, respectively. During these four sampling events, 26, 27, 29, and 35 constituents were detected, respectively. The following transformations in concentration were determined in the waste stream: -100 to 180 percent at the effluent pump and -100 to 85 percent at the reuse train on March 2-3, 2004, and -100 to 1,609 percent at the effluent pump and -100 to 832 percent at the reuse train on July 20-21, 2004; -100 to -37 percent at the effluent pump, -100 to -62 percent at the reuse train, -100 to -56 percent at the chlorine dioxide unit, and -100 to -40 percent at the ultraviolet pilot unit on October 5, 2004; and -100 to -4 percent at the effluent pump, -100 to 17 percent at the reuse train, -100 to -40 percent at the chlorine dioxide unit, and -100 to -14 percent at the ultraviolet pilot unit on October 20, 2004. Samples were tested for detection of household and industrial (organic) wastewater compounds, pharmaceutical compounds, antibiotic compounds, and hormones in influent. Two 'known' endocrine disrupting compounds?17 beta-estradiol (E2) and diethoxynonylphenol? and four 'suspected' endocrine-disrupting compounds?1,4-dichlorobenzene, benzophenone, tris(2-chloroethyl) phosphate, and tris(dichloroisopropyl) phosphate?were detected during these sampling events. Phenanthrene and indole showed the greatest concentration ranges and highest concentrations for the organic wastewater compounds. Acetaminophen showed the greatest concentration range and highest concentration, and warfarin showed the smallest concentration range for the pharmaceutical compounds. Sulfamethoxazole (a sulfonamide) showed the greatest concentration range and highest concentration, and sulfathiozole (also a sulfonamide) showed the smallest concentration range for the antibiotic compounds. Two hormones, 17 beta-estradiol (E2) and estrone (E1), were detected in influent. Samples were also tested for detection of organic wastewater compounds, pharmaceutical compounds, antibiotic compounds, and hormones in effluent. Indole showed the greatest concentration range and highest concentration, and triphenyl phosphate showed the smallest concentration range for the organic wastewater compounds. Dehydronifedipine showed the greatest concentration range and highest concentration, and warfarin had the smallest concentration range for the pharmaceutical compounds. Anhydro-erythromycin (a macrolide degradation product) showed the greatest concentration range, and sulfadiazine (a sulfonamide) and tetracycline showed the lowest concentration ranges for the antibiotic compounds. One hormone, 17 beta-estradiol (E2), was det
Triply differential (e,2e) studies of phenol
NASA Astrophysics Data System (ADS)
da Silva, G. B.; Neves, R. F. C.; Chiari, L.; Jones, D. B.; Ali, E.; Madison, D. H.; Ning, C. G.; Nixon, K. L.; Lopes, M. C. A.; Brunger, M. J.
We have measured (e,2e) triple differential cross sections (TDCS) for the electron-impact ionisation of phenol with coplanar asymmetrical kinematics for an incident electron energy of 250 eV. Experimental measurements of the angular distribution of the slow outgoing electrons at 20 eV are obtained when the incident electron scatters through angles of -5°, -10°, and -15°, respectively. The TDCS data are compared with calculations performed within the molecular 3-body distorted wave model. In this case, a mixed level of agreement, that was dependent on the kinematical condition being probed, was observed between the theoretical and experimental results in the binary peak region. The experimental intensity of the recoil features under all kinematical conditions was relatively small, but was still largely underestimated by the theoretical calculations.
Three body effects in low energy (e,2e) processes
Rasch, J. [Institut de Physique, Laboratoire de Physique Moleculaire et des Collisions, Technopole Metz 2000, Rue Arago (France); Whelan, Colm T. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge, CB3 9EW (United Kingdom)
Within the last two years a number of highly refined measurements have been performed on H targets which have yielded accurate absolute data for a range of energies and geometries and it would appear that the experimental situation for this, the simplest of atomic targets is now resolved. The theoretical situation is however far from satisfactory and in this paper we will analysis some of the main approaches and characterize their strengths and their weaknesses. We have developed a numerical method which allows us to evaluate triple differential cross sections (TDCS) using the most complex position dependent analytic ansatz wave function and we will present results, using this for low energy (e,2e) processes. We will see that this approach fails when incident channel effects, such as target polarization are likely to be strong.
Triply differential (e,2e) studies of phenol
Silva, G. B. da [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Universidade Federal de Mato Grosso, Barra do Garças, MT 78600-000 (Brazil); Neves, R. F. C. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Instituto Federal do Sul de Minas Gerais, Câmpus Poços de Caldas, MG (Brazil); Departamento de Física, UFJF, Juiz de Fora, 36036-330, MG (Brazil); Chiari, L.; Jones, D. B. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Ali, E.; Madison, D. H. [Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409 (United States); Ning, C. G. [Department of Physics, State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084 (China); Nixon, K. L.; Lopes, M. C. A. [Departamento de Física, UFJF, Juiz de Fora, 36036-330, MG (Brazil); Brunger, M. J., E-mail: firstname.lastname@example.com [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia)
We have measured (e,2e) triple differential cross sections (TDCS) for the electron-impact ionisation of phenol with coplanar asymmetrical kinematics for an incident electron energy of 250 eV. Experimental measurements of the angular distribution of the slow outgoing electrons at 20 eV are obtained when the incident electron scatters through angles of ?5°, ?10°, and ?15°, respectively. The TDCS data are compared with calculations performed within the molecular 3-body distorted wave model. In this case, a mixed level of agreement, that was dependent on the kinematical condition being probed, was observed between the theoretical and experimental results in the binary peak region. The experimental intensity of the recoil features under all kinematical conditions was relatively small, but was still largely underestimated by the theoretical calculations.
E2F mediates enhanced alternative polyadenylation in proliferation
Background The majority of mammalian genes contain multiple poly(A) sites in their 3' UTRs. Alternative cleavage and polyadenylation are emerging as an important layer of gene regulation as they generate transcript isoforms that differ in their 3' UTRs, thereby modulating genes' response to 3' UTR-mediated regulation. Enhanced cleavage at 3' UTR proximal poly(A) sites resulting in global 3' UTR shortening was recently linked to proliferation and cancer. However, mechanisms that regulate this enhanced alternative polyadenylation are unknown. Results Here, we explored, on a transcriptome-wide scale, alternative polyadenylation events associated with cellular proliferation and neoplastic transformation. We applied a deep-sequencing technique for identification and quantification of poly(A) sites to two human cellular models, each examined under proliferative, arrested and transformed states. In both cell systems we observed global 3' UTR shortening associated with proliferation, a link that was markedly stronger than the association with transformation. Furthermore, we found that proliferation is also associated with enhanced cleavage at intronic poly(A) sites. Last, we found that the expression level of the set of genes that encode for 3'-end processing proteins is globally elevated in proliferation, and that E2F transcription factors contribute to this regulation. Conclusions Our results comprehensively identify alternative polyadenylation events associated with cellular proliferation and transformation, and demonstrate that the enhanced alternative polyadenylation in proliferative conditions results not only in global 3' UTR shortening but also in enhanced premature cleavage in introns. Our results also indicate that E2F-mediated co-transcriptional regulation of 3'-end processing genes is one of the mechanisms that links enhanced alternative polyadenylation to proliferation. PMID:22747694
Modulation of the cytosolic androgen receptor in striated muscle by sex steroids
NASA Technical Reports Server (NTRS)
Rance, N. E.; Max, S. R.
The effects of orchiectomy (GDX) and of subsequent administration of testosterone propionate (TP) or 17(beta)-estradiol (E2) on the maximum binding (Bmax) and apparent Kd of the cytosolic androgen receptor in levator ani (LA) and skeletal muscles of adult male Sprague-Dawley rats are investigated experimentally. The results are presented in graphs and discussed. In LA, BMAX is found to rise from a control level of 2.5 fmol/mg protein to 280, 600, 478, and 133 percent of control at 12 h, 14 d, 30 d, and 44 d after GDX, respectively, while Kd increased only insignificantly (from 680 to 960 fM); Bmax is held at control levels for 6 h by cycloheximide given at GDX, is unaffected by TP given at 30 d, and is further increased (by 480 percent at 44 d) by administration of E2 at 30 d. Bmax in skeletal muscles is found to increase to 139, 212, 220, and 158 percent of control at 12 h, 14 d, 30 d, and 44 d, respectively; Bmax is returned to control at 44 d by TP at 30 d but is not affected by E2. The effect of E2 in LA is attributed to either induction of the cytosolic receptor or a decreased rate of receptor degradation.
Effect of sex-steroid hormones, testosterone and estradiol, on humoral immune parameters of gilthead seabream.
Cuesta, A; Vargas-Chacoff, L; García-López, A; Arjona, F J; Martínez-Rodríguez, G; Meseguer, J; Mancera, J M; Esteban, M A
The role of sex-steroid hormones, testosterone (T) and 17beta-estradiol (E2), on the humoral immune parameters of the teleost gilthead seabream Sparus aurata was studied attempting to deepen on the knowledge of the immune-reproductive system interactions. Fish were injected intraperitoneally with coconut oil containing different dosages of T (0, 2, or 5 microg g(-1) body weight [bw]) or E2 (0, 1, or 2 microg g(-1) bw) and sampled 1, 3, and 7 days later. Hormonal levels and immune parameters (complement, peroxidase and antiprotease activities and IgM levels) were determined in plasma. Plasma hormone levels peaked at 1 day post-injection decreasing thereafter. Treatment with T significantly increased both complement and peroxidase activities after 3 days of injection but antiprotease activity and IgM levels remained unchanged. Treatment with E2 enhanced complement activity 1 day post-injection while decreased it after 3 and 7 days. However, peroxidase activity increased at 3 and 7 days post-injection while total IgM levels decreased. Implications of T and E2 in the immune-reproductive system interactions were discussed. PMID:17349804
Prostaglandin E2 Prevents Disuse-Induced Cortical Bone Loss
NASA Technical Reports Server (NTRS)
Jee, Webster S. S.; Akamine, T.; Ke, Hua Zhu; Li, Xiao Jian; Tang, L. Y.; Zeng, Q. Q.
The object of this study was to determine whether prostaglandin E2 (PGE2) can prevent disuse (underloaded)-induced cortical bone loss as well as add extra bone to underloaded bones. Thirteen-month-old retired female Sprague-Dawley breeders served as controls or were subjected to simultaneous right hindlimb immobilization by bandaging and daily subcutaneous doses of 0, 1, 3, or 6 mg PGE2/kg/d for two and six weeks. Histomorphometric analyses were performed on double-fluorescent labeled undecalcified tibial shaft sections (proximal to the tibiofibular junction). Disuse-induced cortical bone loss occurred by enlarging the marrow cavity and increasing intracortical porosity. PGE2 treatment of disuse shafts further increased intracortical porosity above that in disuse alone controls. This bone loss was counteracted by enhancement of periosteal and corticoendosteal bone formation. Stimulation of periosteal and corticoendosteal bone formation slightly enlarged the total tissue (cross-sectional) area and inhibited marrow cavity enlargement. These PGE2-induced activities netted the same percentage of cortical bone with a different distribution than the beginning and age related controls. These findings indicate the PGE2-induced increase in bone formation compensated for the disuse and PGE2-induced bone loss, and thus prevented immobilization induced bone loss.
The role of E2f4 in cell cycle exit and bone development
Miller, Emily S. (Emily Sun Young)
Members of the E2F family of transcription factors are critical downstream effectors of the pocket protein family and mediate the regulation of genes required for cellular proliferation. The repressive E2Fs act in association ...
Reproductive and thyroid hormone profiles in captive Western fence lizards (Sceloporus occidentalis) after a period of brumation.
Brasfield, Sandra M; Talent, Larry G; Janz, David M
Seasonal fluctuation in serum concentrations of sex steroid (testosterone [T] and 17beta-estradiol [E(2)]) and thyroid (triiodothyronine [T(3)] and thyroxine [T(4)]) hormones was determined in captive Western fence lizards (Sceloporus occidentalis). Samples were collected from male and female breeding pairs weekly for a 4-month period after their emergence from artificial brumation. Circulating levels of E(2) corresponded with the expected vitellogenic and ovulatory cycles in females, and surprisingly, E(2) in males followed a similar pattern, indicating a possible role in breeding behavior. Serum T was elevated in male lizards for the first 6 weeks after emergence from brumation, possibly related to an increase in the onset of active spermatogenesis. Thyroid hormones showed little cyclical activity throughout the breeding period, with the exception of small increases of T(3) at weeks 8 and 16, possibly implying an active role of this hormone with ovulation in females. Overall, these baseline hormone data are not only useful in developing this animal as a laboratory reptile model for assessment of endocrine-mediated toxicity, but also of value for understanding herpetological endocrinology and for application in the conservation of threatened species. Zoo Biol 27:36-48, 2008. (c) 2007 Wiley-Liss, Inc. PMID:19360602
Uterine progesterone receptors in the aged golden hamster.
Blaha, G C; Leavitt, W W
Uterine capacity to form cytoplasmic progesterone receptor was compared in ovariectomized golden hamsters at three months and 15-17 months of age. A dose-response test with 17beta-estradiol(E2) showed that the uterine content of progesterone receptor (pmole/uterus) was equal in young and old at all dose levels. However, heavier old uteri had less receptor per gm tissue. Old and young hamsters were mated, ovariectomized on day 7 post coitum and after two weeks, all were given the same dose of E2. Endometrium was separated from myometrium before analysis of progesterone receptor. Myometrium was analyzed for both estrogen and progesterone receptors. Myometrium of both groups had comparable levels of both receptors. The mean concentration of progresterone receptor (pmole/gm tissue) was higher in old endometrium. Some old animals with liver, kidney and adrenal disease had more endometrial reaction after E2 treatment. A few with low endometrial receptor levels had normal livers but at least one sterile uterine horn. There was, however, no general decline with age in intrinsic uterine capacity to form progesterone receptors. PMID:744855
Effects of postoperative adjuvant chemotherapy and radiotherapy on ovarian function in women undergoing treatment for soft tissue sarcoma
Shamberger, R.C.; Sherins, R.J.; Ziegler, J.L.; Glatstein, E.; Rosenberg, S.A.
Ovarian function was evaluated in 11 women 16 to 43 years of age at treatment who received doxorubicin, cyclophosphamide, and high doses of methotrexate with or without radiotherapy in adjuvant therapy of soft tissue sarcoma. Five women (16-33 yr old) who received chemotherapy alone or combined with radiotherapy only at sites distant from the ovaries (chest wall, thigh, and leg) had minimal menstrual irregularities or temporary cessation of menses during therapy; cyclic menses returned promptly after therapy. Gonadotropin levels (expressed as means +/- SD (follicle-stimulating hormone (FSH), 10 +/- 5 mlU/ml; luteinizing hormone (LH), 10 +/- 4 mlU/ml) and 17 beta-estradiol (E2) levels (means +/- SD, 208 +/- 147 pg/ml) were normal. By contrast, 4 older women (ages 36-43 yr) who received similar treatment developed persistent amenorrhea with postmenopausal levels of gonadotropin (FSH, 108 +/- 29 mlU/ml; LH, 72 +/- 19 mlU/ml) and E2 (19 +/- 8 pg/ml). Two additional women (ages 21 and 39 yr) who received radiation (7,000 rad) to the pelvis plus chemotherapy developed prompt cessation of menses and became functional castrates (FSH, 77 and 80 mlU/ml; LH, 40 and 58 mlU/ml; E2, 10 and 19 pg/ml). However, this result would be expected from the radiation dose alone. The data demonstrated that ovarian dysfunction may follow the use of doxorubicin, cyclophosphamide, and high doses of methotrexate and that the injury is age related.
Effect of polar day on plasma profiles of melatonin, testosterone, and estradiol in high-Arctic Lapland Longspurs.
Hau, Michaela; Romero, L Michael; Brawn, Jeff D; Van't Hof, Thomas J
In polar habitats, continuous daylight (polar day) can prevail for many weeks or months around the summer solstice. In the laboratory, continuous light conditions impair or disrupt circadian rhythms in many animals. To determine whether circadian rhythms are disrupted under natural polar day conditions in a species that is only a summer resident in polar regions we analyzed diel rhythms in plasma concentrations of melatonin, testosterone (T), and 17-beta estradiol (E(2)) during the summer solstice in Arctic-breeding Lapland Longspurs (Calcarius lapponicus). We compared these profiles to those of conspecifics housed in outdoor aviaries at a mid-latitude site in Seattle, Washington, during spring, summer, fall, and winter. Under polar day conditions plasma melatonin concentrations of Lapland Longspurs were strongly suppressed, but still showed a significant diel rhythm. Likewise, plasma T in males, and E(2) in females, showed significant diel changes in Arctic birds. Lapland Longspurs housed at mid-latitude in Seattle showed high-amplitude melatonin cycles at all times of the year, and the duration of the nightly melatonin secretion was positively correlated with the duration of the dark phase. We found no diel changes in plasma T in Seattle males in May, but Seattle females showed significant day/night differences in plasma E(2) in May. The data suggest that even under polar day conditions diel rhythms can persist. The maintenance of hormone rhythms could provide a physiological basis to reports of rhythmic behavior in many birds during the Arctic summer. PMID:11944971
Characterization of the nuclear localization signal of high risk HPV16 E2 protein
Kristin Klucevsek; Mary Wertz; John Lucchi; Anna Leszczynski; Junona. Moroianu
The E2 protein of high risk human papillomavirus type 16 (HPV16) contains an amino-terminal (N) domain, a hinge (H) region and a carboxyl-terminal (C) DNA-binding domain. Using enhanced green fluorescent protein (EGFP) fusions with full length E2 and E2 domains in transfection assays in HeLa cells, we found that the C domain is responsible for the nuclear localization of E2
E2F-1 Potentiates Cell Death by Blocking Antiapoptotic Signaling Pathways
Andrew C Phillips; Mary K Ernst; Stewart Bates; Nancy R Rice; Karen H Vousden
The E2F family of transcription factors plays an essential role in promoting cell cycle progression, and one member of the family, E2F-1, is also capable of inducing apoptosis. We show here that E2F-1 can induce apoptosis by a death receptor–dependent mechanism, by downregulating TRAF2 protein levels and inhibiting activation of antiapoptotic signals including NF-?B. In this way, E2F-1 expression can
In vivo delivery of bovine viral diahorrea virus, E2 protein using hollow mesoporous silica nanoparticles
NASA Astrophysics Data System (ADS)
Mahony, D.; Cavallaro, A. S.; Mody, K. T.; Xiong, L.; Mahony, T. J.; Qiao, S. Z.; Mitter, N.
Our work focuses on the application of mesoporous silica nanoparticles as a combined delivery vehicle and adjuvant for vaccine applications. Here we present results using the viral protein, E2, from bovine viral diarrhoea virus (BVDV). BVDV infection occurs in the target species of cattle and sheep herds worldwide and is therefore of economic importance. E2 is a major immunogenic determinant of BVDV and is an ideal candidate for the development of a subunit based nanovaccine using mesoporous silica nanoparticles. Hollow type mesoporous silica nanoparticles with surface amino functionalisation (termed HMSA) were characterised and assessed for adsorption and desorption of E2. A codon-optimised version of the E2 protein (termed Opti-E2) was produced in Escherichia coli. HMSA (120 nm) had an adsorption capacity of 80 ?g Opti-E2 per mg HMSA and once bound E2 did not dissociate from the HMSA. Immunisation studies in mice with a 20 ?g dose of E2 adsorbed to 250 ?g HMSA was compared to immunisation with Opti-E2 (50 ?g) together with the traditional adjuvant Quillaja saponaria Molina tree saponins (QuilA, 10 ?g). The humoral responses with the Opti-E2/HMSA nanovaccine although slightly lower than those obtained for the Opti-E2 + QuilA group demonstrated that HMSA particles are an effective adjuvant that stimulated E2-specific antibody responses. Importantly the cell-mediated immune responses were consistently high in all mice immunised with Opti-E2/HMSA nanovaccine formulation. Therefore we have shown the Opti-E2/HMSA nanoformulation acts as an excellent adjuvant that gives both T-helper 1 and T-helper 2 mediated responses in a small animal model. This study has provided proof-of-concept towards the development of an E2 subunit nanoparticle based vaccine.Our work focuses on the application of mesoporous silica nanoparticles as a combined delivery vehicle and adjuvant for vaccine applications. Here we present results using the viral protein, E2, from bovine viral diarrhoea virus (BVDV). BVDV infection occurs in the target species of cattle and sheep herds worldwide and is therefore of economic importance. E2 is a major immunogenic determinant of BVDV and is an ideal candidate for the development of a subunit based nanovaccine using mesoporous silica nanoparticles. Hollow type mesoporous silica nanoparticles with surface amino functionalisation (termed HMSA) were characterised and assessed for adsorption and desorption of E2. A codon-optimised version of the E2 protein (termed Opti-E2) was produced in Escherichia coli. HMSA (120 nm) had an adsorption capacity of 80 ?g Opti-E2 per mg HMSA and once bound E2 did not dissociate from the HMSA. Immunisation studies in mice with a 20 ?g dose of E2 adsorbed to 250 ?g HMSA was compared to immunisation with Opti-E2 (50 ?g) together with the traditional adjuvant Quillaja saponaria Molina tree saponins (QuilA, 10 ?g). The humoral responses with the Opti-E2/HMSA nanovaccine although slightly lower than those obtained for the Opti-E2 + QuilA group demonstrated that HMSA particles are an effective adjuvant that stimulated E2-specific antibody responses. Importantly the cell-mediated immune responses were consistently high in all mice immunised with Opti-E2/HMSA nanovaccine formulation. Therefore we have shown the Opti-E2/HMSA nanoformulation acts as an excellent adjuvant that gives both T-helper 1 and T-helper 2 mediated responses in a small animal model. This study has provided proof-of-concept towards the development of an E2 subunit nanoparticle based vaccine. Electronic supplementary information (ESI) available: Desorption studies of Opti-E2 bound HMSA. See DOI: 10.1039/c4nr01202j
Regulation of E2F-1 gene expression in human breast cancer cells
Ngwenya, Sharon Khethiwe
that hormonal activation of pE2F-1jm1 and pM-NFYA are dependent on non-genomic pathways in which E2 activates cAMP/protein kinase A. Hormone-dependent regulation of E2F-1 gene expression in ZR-75 and MCF-7 involves different mechanisms, demonstrating...
Molecular Links between the E2 Envelope Glycoprotein and Nucleocapsid Core in Sindbis Virus
Baker, Timothy S.
, amino acids; cdE1, cytoplasmic domain of E1; cdE2, cytoplasmic domain of E2; CHIKV, Chikungunya virusMolecular Links between the E2 Envelope Glycoprotein and Nucleocapsid Core in Sindbis Virus Jinghua; virus assembly; cytoplasmic domain A three-dimensional reconstruction of Sindbis virus at 7.0 Ĺ
The function of E2F6 in the Polycomb complex
Courel, María F. (María Federica)
The E2F family of transcription factors are known cell cycle regulators that function at the G1/S transition. Unlike other E2Fs, E2F6 does not activate transcription and is not regulated by pocket protein binding. Instead, ...
Inhibition of the entomopathogenic fungus Metarhizium anisopliae in vitro by the bed bug defensive secretions (E)-2-hexenal and (E)-2-octenal
Technology Transfer Automated Retrieval System (TEKTRAN)
The two major aldehydes (E)-2-hexenal and (E)-2-octenal emitted as defensive secretions by bed bugs Cimex lectularius L. (Hemiptera: Cimicidae), inhibit the in vitro growth of Metarhizium anisopliae (Metsch.) Sokorin (Hypocreales: Clavicipitaceae). These chemicals inhibit fungal growth by direct con...
Autoionization in electron - helium collisions: an (e, 2e) investigation
NASA Astrophysics Data System (ADS)
Samardzic, O.; Campbell, L.; Brunger, M. J.; Kheifets, A. S.; Weigold, E.
In this (e, 2e) study into the n = 2 autoionization resonances of helium we present results for the triple differential cross sections (TDCS) at an incident energy of 80 eV. The scattered-electron angle is 0953-4075/30/19/024/img8 and the range of ejected-electron scattering angles are between 0953-4075/30/19/024/img9 and 0953-4075/30/19/024/img10. The measured coincidence ejected-electron spectra are analysed in terms of the Shore - Balashov parametrization to obtain the direct TDCS 0953-4075/30/19/024/img11 and the resonance parameters 0953-4075/30/19/024/img12 and 0953-4075/30/19/024/img13 for the 0953-4075/30/19/024/img14 and 0953-4075/30/19/024/img15 resonances as a function of the ejected-electron momentum. As in our previous studies (1995 J. Phys. B: At. Mol. Phys. 28 728, 1997 J. Phys. B: At. Mol. Phys. 30 3267) these derived parameters are compared with the results of a calculation based within the distorted-wave Born approximation (DWBA) framework. The post-collision-interaction (PCI) related energy shift 0953-4075/30/19/024/img16 was also determined in the present experiments. Given the somewhat lower beam energy of this work compared to our earlier investigations (94.6 - 99.6 eV), we had anticipated that we would see larger PCI effects and that our DWBA calculation would prove to be too simplistic to provide a realistic description of the reaction mechanism. In fact, the calculated parameters 0953-4075/30/19/024/img17 agree quite well with the experimental results, both indicating strong correlations between the resonance amplitudes and the direct ionization amplitudes. Furthermore, 0953-4075/30/19/024/img16 was, to within the uncertainties in the data, found to be zero across the entire range of ejected-electron momenta studied.
Nucleotide sequence and regulation of the adenovirus type 3 E2A early promoter.
Heysen, A; Verwaerde, P; D'Halluin, J C
The nucleotide sequence of the adenovirus serotype 3 E2A early promoter has been determined. In contrast to Ad2, the Ad3 E2A early promoter possessed only one TATA-like box and one nuclear transcription factor E2F binding site and lacked the silencer sequences; however, as in Ad2, the ATF binding site was present. Moreover, the Ad3 E2A promoter harbored a protein binding sequence recognized by the SP1 factor. By transient expression analysis in HeLa cells, we demonstrated that the E1A gene products of Ad3 and Ad2 stimulated Ad3 E2A transcription. In competition experiments, the Ad3 E2A promoter was used in preference to the Ad2 E2A promoter. PMID:1825252
EGFR Signaling Inhibits E2F1-Induced Apoptosis in Vivo: Implications for Cancer Therapy
NSDL National Science Digital Library
Doron Ginsberg (Bar Ilan University; Mina and Everard Goodman Faculty of Life Science REV)
The retinoblastoma tumor suppressor (RB) restricts cell proliferation by regulating members of the E2F family of transcription factors. In human tumors RB is often inactivated, resulting in aberrant E2F-dependent transcription and uncontrolled proliferation. One of the E2F proteins, E2F1, can also induce apoptosis. The extent of E2F1-induced apoptosis is known to be tissue- and cell-specific, but until now, it has been unclear what variables determine cellular sensitivity to E2F1-induced apoptosis in vivo. A recent study reveals epidermal growth factor receptor (EGFR) signaling to be one such variable, as EGFR signaling cooperates with RB in inhibiting E2F1-induced apoptosis. This finding raises the possibility that therapeutic manipulation of EGFR signaling may specifically trigger the death of cancer cells with inactive RB, thereby enabling "targeted" cancer treatments.
The swine CD81 enhances E2-based DNA vaccination against classical swine fever.
Li, Wenliang; Mao, Li; Zhou, Bin; Liu, Xia; Yang, Leilei; Zhang, Wenwen; Jiang, Jieyuan
Classical swine fever (CSF) is a highly contagious and economically important viral disease that affects the pig industry worldwide. The glycoprotein E2 of CSFV can induce neutralizing antibodies and protective immunity, and is widely used for novel vaccine development. The objective of this study was to explore whether a tetraspanin molecule CD81 could improve the immune responses of an E2-based DNA vaccine. Plasmids pVAX-CD81, pVAX-E2 and pVAX-CD81-E2 were constructed and the expression of target proteins was confirmed in BHK-21 cells by indirect immunofluorescence assay. BALB/c mice were divided into 5 groups and immunized with different plasmids (pVAX-E2, pVAX-CD81-E2, pVAX-E2+pVAX-CD81, pVAX-CD81 and PBS) three times with two weeks interval. The results showed that the introduction of CD81 promoted higher humoral and cellular immune responses than E2 expression alone (P<0.05). In addition, immunization with pVAX-CD81-E2 induced stronger immune responses than pVAX-E2+pVAX-CD81. Furthermore, four groups of pigs were immunized with pVAX-E2, pVAX-CD81-E2, pVAX-CD81 and PBS, respectively. Humoral and cellular immune responses detection showed similar results with those in mice. Compared to pVAX-E2, pVAX-CD81-E2 induced higher titers of neutralizing antibodies after viral challenge and conferred stronger protection. These results confirmed the capacity of swine CD81 enhancing the humoral and cellular responses with an adjuvant effect on CSFV DNA vaccine. This is the first report demonstrating the adjuvant effect of CD81 to enhance the DNA vaccination for swine pathogen. PMID:26051512
Pumilio facilitates miRNA regulation of the E2F3 oncogene
Miles, Wayne O.; Tschöp, Katrin; Herr, Anabel; Ji, Jun-Yuan; Dyson, Nicholas J.
E2F transcription factors are important regulators of cell proliferation and are frequently dysregulated in human malignancies. To identify novel regulators of E2F function, we used Drosophila as a model system to screen for mutations that modify phenotypes caused by reduced levels of dE2F1. This screen identified components of the Pumilio translational repressor complex (Pumilio, Nanos, and Brain tumor) as suppressors of dE2F1-RNAi phenotypes. Subsequent experiments provided evidence that Pumilio complexes repress dE2F1 levels and that this mechanism of post-transcriptional regulation is conserved in human cells. The human Pumilio homologs Pum 1 and Pum 2 repress the translation of E2F3 by binding to the E2F3 3? untranslated region (UTR) and also enhance the activity of multiple E2F3 targeting microRNAs (miRNAs). E2F3 is an oncogene with strong proliferative potential and is regularly dysregulated or overexpressed in cancer. Interestingly, Pumilio/miRNA-mediated regulation of E2F3 is circumvented in cancer cells in several different ways. Bladder carcinomas selectively down-regulate miRNAs that cooperate with Pumilio to target E2F3, and multiple tumor cell lines shorten the 3? end of the E2F3 mRNA, removing the Pumilio regulatory elements. These studies suggest that Pumilio–miRNA repression of E2F3 translation provides an important level of E2F regulation that is frequently abrogated in cancer cells. PMID:22345517
Interaction between the catalytic site and the A-M3 linker stabilizes E2/E2P conformational states of Na+,K+-ATPase.
Toustrup-Jensen, Mads; Vilsen, Bente
The consequences of mutations Ile(265) --> Ala, Thr(267) --> Ala, Gly(271) --> Ala, and Gly(274) --> Ala for the partial reaction steps of the Na(+),K(+)-ATPase transport cycle were analyzed. The mutated residues are part of the long loop ("A-M3 linker") connecting the cytoplasmic A-domain with transmembrane segment M3. It was found that mutation Ile(265) --> Ala displaces the E(1)-E(2) and E(1)P-E(2)P equilibria in favor of E(1)/E(1)P, whereas mutations Thr(267) --> Ala, Gly(271) --> Ala, and Gly(274) --> Ala displace these conformational equilibria in favor of E(2)/E(2)P. The mutations affect both the rearrangement of the cytoplasmic domains (seen by changes in phosphoenzyme properties and apparent ATP/vanadate affinities) and the membrane sector (indicated by change in K(+)/Rb(+) deocclusion rate). Destabilization of E(2)/E(2)P in Ile(265) --> Ala, as well as a direct effect on the intrinsic affinity of the E(2) form for vanadate, may be explained on the basis of the E(2) crystal structures of the Ca(2+)-ATPase, showing interaction of the equivalent isoleucine with conserved residues near the catalytic region of the P-domain. The rate of phosphorylation from ATP was unaffected in Ile(265) --> Ala, indicating a lack of interference with the catalytic function in E(1)/E(1)P. The effects of mutations Thr(267) --> Ala, Gly(271) --> Ala, and Gly(274) --> Ala provide the first evidence in the literature of a relative stabilization of E(2)/E(2)P resulting from perturbation of the A-M3 linker region. These mutations may lead to increased strain of the A-M3 linker in E(1)/E(1)P, increased stability of the A3 helix of the A-M3 linker in E(2)/E(2)P, and/or a change of the orientation of the A3 helix, facilitating its interaction with the P-domain. PMID:15574410
Effects of estrogen and gender on cataractogenesis induced by high-LET radiation
Henderson, M.A.; Rusek, A.; Valluri, S.; Garrett, J.; Lopez, J.; Caperell-Grant, A.; Mendonca, M.; Bigsby, R.; Dynlacht, J.
Planning for long-duration manned lunar and interplanetary missions requires an understanding of radiation-induced cataractogenesis. Previously, it was demonstrated that low-linear energy transfer (LET) irradiation with 10 Gy of {sup 60}Co {gamma} rays resulted in an increased incidence of cataracts in male rats compared to female rats. This gender difference was not due to differences in estrogen, since male rats treated with the major secreted estrogen 17-{beta}-estradiol (E2) showed an identical increase compared to untreated males. We now compare the incidence and rate of progression of cataracts induced by high-LET radiation in male and female Sprague-Dawley rats. Rats received a single dose of 1 Gy of 600 MeV {sup 56}Fe ions. Lens opacification was measured at 2-4 week intervals with a slit lamp. The incidence and rate of progression of radiation-induced cataracts was significantly increased in the animals in which estrogen was available from endogenous or exogenous sources. Male rats with E2 capsules implanted had significantly higher rates of progression compared to male rats with empty capsules implanted (P = 0.025) but not compared to the intact female rats. These results contrast with data obtained after low-LET irradiation and suggest the possibility that the different types of damage caused by high- and low-LET radiation may be influenced differentially by steroid sex hormones.
Sex steroids levels in the plasma and testis during the reproductive cycle of lizard Podarcis s. sicula Raf.
Andň, S; Ciarcia, G; Panno, M L; Imbrogno, E; Tarantino, G; Buffone, M; Beraldi, E; Angelini, F; Botte, V
Progesterone (P), 17-OH-progesterone (17-OH-P), androstenedione (A), dehydroepiandrosterone (DHEA), testosterone (T), 5 alpha-dihydrotestosterone (5 alpha-DHT), and 17 beta-estradiol (E2) were measured by RIA in plasma and testes of 114 males of the oviparous lizard Podarcis s. sicula raf, a species that displays annual hibernating cycles. Hormones were determined each month from January until December, except for August. Testosterone peaked at 174.8 ng/ml of plasma after emergence (March), while 5 alpha-DHT and A peaked in April. Plasma DHEA increased during hibernation. During the refractory period there were progressive increases in P and E2 plasma levels. The testicular peak of T, in March, coincided with that observed in plasma. The striking increases in testicular T and A in early July occurred at a time when plasma androgen concentrations were low. 5 alpha-DHT increased in April when spermatogenesis with spermiation occurred and then decreased alongside a second peak of T. There is an apparent separation of plasma and testicular androgen concentrations during the reproductive cycle. PMID:1532946
Profiles of sex steroids, fecundity, and spawning of the curimată-pacu Prochilodus argenteus in the Săo Francisco River, downstream from the Tręs Marias Dam, Southeastern Brazil.
Arantes, Fábio P; Santos, Helio B; Rizzo, Elizete; Sato, Yoshimi; Bazzoli, Nilo
The present study evaluated for the first time sex steroid profiles and fecundity in females of Prochilodus argenteus from two sections of the Săo Francisco River Brazil, downstream from the Tręs Marias Dam, which influences characteristics of their water habitat. The model species in the study, P. argenteus, is an important commercial and recreational species in Brazil. In the region closest to the dam (section 1), females did not reach final oocyte maturation, failed to spawn, and displayed lesser circulating concentrations of testosterone, 17(-hydroxyprogesterone (17(-P) and 17beta-estradiol (E2) than those farther downstream of the dam (section 2). The endocrine and fecundity deficiencies probably are attributed to lower water temperature and oxygen concentration in (section 1). The follicular atresia rate in the region closest to the dam (26%) was greater than those fish captured farther downstream of the dam (13%), after the Abaeté River (section 2). Variations in testosterone, E2 and 17(-P concentrations in section 2, followed gonadal maturation which are typical features of species which have seasonal reproduction, group-synchronous oocyte development, and are single batch spawners such as P. argenteus. Results document the first evidence of endocrine and reproductive dysfunctions caused by inadequate water conditions in a wild population of the migratory species P. argenteus in the Săo Francisco River, downstream from the Tręs Marias dam. PMID:19683404
Homeobox gene HOPX is epigenetically silenced in human uterine endometrial cancer and suppresses estrogen-stimulated proliferation of cancer cells by inhibiting serum response factor.
Yamaguchi, Shinichiro; Asanoma, Kazuo; Takao, Tomoka; Kato, Kiyoko; Wake, Norio
HOPX (homeodomain only protein X) is a newly identified homeobox gene whose loss of expression has been reported for several types of neoplasm. Although we found most human uterine endometrial cancers (HEC) defective in HOPX expression, genetic mutations in the HOPX gene were undetectable. As is the case with several tumor suppressor genes, the promoter region of HOPX is densely methylated in HEC tissue samples obtained by laser capture microdissection. HOPX mRNA and protein levels were reduced in the majority of samples, and this correlated with hypermethylation of the HOPX promoter. Forced expression of HOPX resulted in a partial block in cell proliferation, in vivo tumorigenicity and c-fos gene expression in HEC and MCF7 cells in response to 17beta-estradiol (E(2)) stimulation. Analysis of the serum response element (SRE) of c-fos gene promoter showed that the effect of HOPX expression is associated with inhibition of E(2)-induced c-fos activation through the serum response factor (SRF) motif. Knockdown of HOPX in immortalized human endometrial cells resulted in accelerated proliferation. Our study indicates that transcriptional silencing of HOPX results from hypermethylation of the HOPpromoter, which leads to HEC development. PMID:19173292
The use of modelling to predict levels of estrogens in a river catchment: how does modelled data compare with chemical analysis and in vitro yeast assay results?
Balaam, Jan L; Grover, Darren; Johnson, Andrew C; Jürgens, Monika; Readman, James; Smith, Andy J; White, Stefan; Williams, Richard; Zhou, John L
Effluent discharges at Rodbourne sewage treatment works (STWs) were assessed using chemical and in vitro biological analysis as well as modelling predictions. Results showed that Rodbourne STW discharged less estrone (E1) than expected, but similar 17beta-estradiol (E2) and 17alpha-ethinyl estradiol (EE2) to those predicted by a widely cited effluent prediction model. The Exposure Analysis Modelling System (EXAMS) model was set up using measured effluent concentrations as its starting point to predict estrogen concentrations along a 10 km length of the receiving water of the River Ray. The model adequately simulated estrogen concentrations along the river when compared to July 2007 measured data. The model predicted combined estrogen equivalents in reasonable agreement with estrogenicity as measured by passive sampler (POCIS) extracts using the yeast estrogen screen. Using gauged mean flow values for 2007 the model indicated that the most important determinand for estrogen exposure in the Ray was not season, but proximity to the Rodbourne effluent. Thus, fish in the first 3 km downstream of Rodbourne were typically exposed to two or even three times more estrogens than those living 7-10 km further downstream. The modelling indicated that, assuming the effluent estrogen concentrations measured in February 2008 were typical, throughout the year the whole length of the Ray downstream of Rodbourne would be estrogenic, i.e. exceeding the 1 ng/L E2 equivalent threshold for endocrine disruption. PMID:20673965
Effect of thyroid hormone on CYP19 expression in ovarian granulosa cells from gonadotropin-treated immature rats.
Hatsuta, Minoru; Tamura, Kazuhiro; Shimizu, Yoko; Toda, Katsumi; Kogo, Hiroshi
The present study was designed to determine the mechanisms by which serum estradiol levels are enhanced during gonadotropin-induced ovarian development in hypothyroid immature rats. Thyroidectomized (Tx)-immature rats receiving thyroidectomy on day 22 were treated with 8 IU equine chorionic gonadotropin (eCG) at 26 days of age to induce follicular development in ovaries. Ovaries or ovarian granulosa cells were collected on the first proestrus (day 28). Enhanced expression of aromatase (CYP19) mRNA induced by eCG treatment was inhibited by injection of thyroxine (T(4): 5 microg x 6 times) in Tx rats. Ovarian granulosa cells harvested from Tx rats were cultured for 24 h in chemically defined serum-free medium containing gonadotropin in the presence of 3,5,3'-triidothyronine (T(3)). Addition of low doses of T(3) (10(-8), 10(-7) M) to the medium significantly decreased 17beta-estradiol (E(2)) levels, whereas high doses of T(3) (10(-6), 10(-5) M) did not inhibit the levels. Similar effects of T(3) on CYP19 mRNA expression were observed. These results indicate that augmentation of E(2) production in hypothyroid animals may be mediated, in part, via the stimulation of CYP19 mRNA expression in granulosa cells, which is suppressed by thyroid hormone. PMID:15107582
Reduction of primordial follicles caused by maternal treatment with busulfan promotes endometrial adenocarcinoma development in donryu rats.
Yoshida, Midori; Watanabe, Gen; Shirota, Mariko; Maekawa, Akihiko; Taya, Kazuyoshi
Ovarian dysfunction leading to hormonal imbalance plays a crucial role in uterine carcinogenesis in rats as well as women. However, the effects of a reduction in primordial follicles at birth on uterine adenocarcinoma development have hitherto not been determined. The present study was therefore conducted using female Donryu rats, a high incidence rat strain of uterine adenocarcinoma. The animals were maternally exposed to 2.5 or 5.0 mg/kg of busulfan on gestation day 14 to reduce primordial follicles, and were then initiated by intrauterine treatment with N-ethyl-N'-nitro-N-nitrosoguanidine at 11 weeks of age. Both busulfan treatment doses caused earlier occurrence of persistent estrus, with dose-dependence as compared to controls. At 15 months of age, the rats were euthanized. The incidence of uterine adenocarcinomas and multiplicity of uterine neoplastic lesions were significantly increased by the 5.0 mg/kg, but not the 2.5 mg/kg busulfan treatment. Morphologically, the ovaries exposed to busulfan treatment exhibited severe atrophy, with few or no follicles and corpus lutea. Serum 17beta-estradiol (E2), progesterone, and inhibin levels were significantly decreased in the busulfan treatment groups, with a clear dose-relation. Interestingly, only the 5.0 mg/kg busulfan treatment elevated the E2/progesterone ratio. These results provide evidence that the reduction of primordial follicles promotes uterine adenocarcinoma development in rats in association with an earlier occurrence of the persistent estrus status. PMID:16177545
Effects of atrazine on hepatic metabolism and endocrine homeostasis in rainbow trout (Oncorhynchus mykiss)
Salaberria, Iurgi [Department of Zoology and Animal Cell Biology, University of the Basque Country, Apdo. 644, E-48080 Bilbao (Spain); Department of Biology, Norwegian University of Science and Technology, N-7491 Trondheim (Norway)], E-mail: email@example.com; Hansen, Bjorn Henrik [SINTEF Materials and Chemistry, Marine Environmental Technology, N-7465 Trondheim (Norway); Asensio, Vega [Department of Zoology and Animal Cell Biology, University of the Basque Country, Apdo. 644, E-48080 Bilbao (Spain); Olsvik, Pal A. [National Institute of Nutrition and Seafood Research (NIFES), Nordnes, N-5817 Bergen (Norway); Andersen, Rolf A.; Jenssen, Bjorn Munro [Department of Biology, Norwegian University of Science and Technology, N-7491 Trondheim (Norway)
The herbicide atrazine (ATZ) is one of the most widely used pesticides in the world and is now under scrutiny for its alleged capacity to disrupt the endocrine system. Exhibiting negligible interaction with the estrogen receptor (ER), ATZ's mode of action remains to be elucidated. ATZ may act as an inducer of the enzyme aromatase, which converts androgens to estrogens, although other mechanisms should also be taken into consideration such as impairment of hepatic metabolism. Therefore we administered juvenile rainbow trout (Oncorhynchus mykiss) a dose of either 2 or 200 {mu}g ATZ/kg, or of carrier control phosphate buffered saline (PBS) and we measured plasma concentrations of testosterone (T), 17beta-estradiol (E2) and vitellogenin (Vtg) 6 days after exposure. Simultaneously we analyzed hepatic gene expression of cytochrome P450 (CYP) 1A and pi-class glutathione S-transferase (GST-P), and catalase (CAT) activity. Although sex steroid levels showed no significant alterations, we found a dose-dependent increase in Vtg and a concomitant decrease in CYP1A. There was no effect of ATZ on GST-P mRNA levels but GST-P was positively correlated with CYP1A. Also, CYP1A was negatively correlated with liver CAT and E2, and varied with T concentrations in a hormetic manner. The results showed that ATZ can alter hepatic metabolism, induce estrogenic effects and oxidative stress in vivo, and that these effects are linked.
Skp2 suppresses apoptosis in Rb1 deficient tumors by limiting E2F1 activity
Lu, Zhonglei; Bauzon, Frederick; Fu, Hao; Cui, Jinhua; Zhao, Hongling; Nakayama, Keiko; Nakayama, Keiich I.; Zhu, Liang
One mechanism of tumor suppression by pRb is repressing E2F1. Hence, E2f1 deletion diminishes tumorigenesis following Rb1 loss. However, E2F1 promotes both proliferation and apoptosis. It therefore remains unclear how de-repressed E2F1 promotes tumorigenesis. Another mechanism of pRb function is repressing Skp2 to elevate p27 to arrest proliferation. However, Skp2 deletion induced apoptosis, not proliferation arrest, in Rb1 deficient pituitary tumorigenesis. Here, we show that Rb1 deletion induces higher expression of E2F1 target genes in the absence of Skp2. E2F1 binds less cyclin A but more target promoters when Rb1 is deleted with Skp2 knockout or p27T187A knockin, suggesting that stabilized p27 prevents cyclin A from binding and inhibiting E2F1. In Rb1 deficient pituitary tumorigenesis, Skp2 deletion or p27T187A mutation converts E2F1's role from proliferative to apoptotic. These findings delineate a pRb-Skp2-p27-cyclin A-E2F1 pathway that determines whether E2F1 is proliferative or apoptotic in Rb1 deficient tumorigenesis. PMID:24632684
Transcriptional regulation of human RANK ligand gene expression by E2F1
Hu Yan [Department of Stress Biology, Roswell Park Cancer Institute, Buffalo, NY 14263 (United States); Sun Meng [Department of Urology and Cancer Center, University of California at Davis, School of Medicine, 4860 Y Street, Suite 3500, Sacramento, CA 95817 (United States); Graduate Program of Pharmacology and Toxicology, University of California at Davis, Sacramento, CA 95817 (United States); Nadiminty, Nagalakshmi; Lou Wei [Department of Urology and Cancer Center, University of California at Davis, School of Medicine, 4860 Y Street, Suite 3500, Sacramento, CA 95817 (United States); Pinder, Elaine [Department of Urology and Cancer Center, University of California at Davis, School of Medicine, 4860 Y Street, Suite 3500, Sacramento, CA 95817 (United States); Graduate Program of Pharmacology and Toxicology, University of California at Davis, Sacramento, CA 95817 (United States); Gao, Allen C. [Department of Urology and Cancer Center, University of California at Davis, School of Medicine, 4860 Y Street, Suite 3500, Sacramento, CA 95817 (United States); Graduate Program of Pharmacology and Toxicology, University of California at Davis, Sacramento, CA 95817 (United States)], E-mail: firstname.lastname@example.com
Receptor activator of nuclear factor kappa B ligand (RANKL) is a critical osteoclastogenic factor involved in the regulation of bone resorption, immune function, the development of mammary gland and cardiovascular system. To understand the transcriptional regulation of RANKL, we amplified and characterized a 1890 bp 5'-flanking sequence of human RANKL gene (-1782 bp to +108 bp relative to the transcription start site). Using a series of deletion mutations of the 1890 bp RANKL promoter, we identified a 72 bp region (-172 to -100 bp) mediating RANKL basal transcriptional activity. Sequence analysis revealed a putative E2F binding site within this 72 bp region in the human RANKL promoter. Overexpression of E2F1 increased RANKL promoter activity, while down-regulation of E2F1 expression by small interfering RNA decreased RANKL promoter activity. RT-PCR and enzyme linked immunosorbent assays (ELISA) further demonstrated that E2F1 induced the expression of RANKL. Electrophoretic gel mobility shift assays (EMSA) and antibody competition assays confirmed that E2F1 proteins bind to the consensus E2F binding site in the RANKL promoter. Mutation of the E2F consensus binding site in the RANKL promoter profoundly reduced the basal promoter activity and abolished the transcriptional modulation of RANKL by E2F1. These results suggest that E2F1 plays an important role in regulating RANKL transcription through binding to the E2F consensus binding site.
Defensive roles of (E)-2-alkenals and related compounds in heteroptera.
Noge, Koji; Prudic, Kathleen L; Becerra, Judith X
We examined whether shared volatiles found in various heteropteran species and developmental stages function to repel predators. The nymphal dorsal abdominal gland secretions of Riptortus pedestris (Heteroptera: Alydidae) and Thasus acutangulus (Heteroptera: Coreidae), and the metathoracic scent gland secretion of Euschistus biformis (Heteroptera: Pentatomidae) adults were identified by gas chromatography/mass spectrometry (GC/MS). (E)-2-Hexenal, 4-oxo-(E)-2-hexenal (4-OHE), and (E)-2-octenal were found in all three species and deemed likely candidates for repelling predators. In addition to (E)-2-alkenals, the adult E. biformis secreted (E)-2-hexenyl acetate, (E)-2-octenyl acetate, and four hydrocarbons. We evaluated the potential predator repellent properties of these compounds and compound blends against a generalist, cosmopolitan insect predator, the Chinese praying mantid (Mantodea: Mantidae: Tenodera aridifolia sinensis). Mantids that experienced (E)-2-hexenal, (E)-2-octenal, and (E)-2-octenyl acetate moved away from the site of interaction, while 4-OHE and (E)-2-hexenyl acetate did not affect mantid behavior. The compound blends did not have additive or synergistic repellency effects on predator behavior. Compound repellency was not related to compound volatility. Instead, the repellent effect is likely related to predator olfaction, and the affinity of each compound to receptors on the antennae. Our results also suggest the repellents might intensify the visual defensive signals of aposematism (T. acutangulus nymphs) and mimicry (R. pedestris nymphs) in heteropteran bugs. PMID:23054031
Glycogenolytic and antiglycogenolytic prostaglandin E2 actions in rat hepatocytes are mediated via different signalling pathways.
Püschel, G P; Kirchner, C; Schröder, A; Jungermann, K
Prostaglandin E2 has been reported both to stimulate glycogen-phosphorylase activity (glycogenolytic effect) and to inhibit the glucagon-stimulated glycogen-phosphorylase activity (antiglycogenolytic effect) in rat hepatocytes. It was the purpose of this study to resolve this apparent contradiction and to characterize the signalling pathways and receptor subtypes involved in the opposing prostaglandin E2 actions. Prostaglandin E2 (10 microM) increased glucose output, glycogen-phosphorylase activity and inositol trisphosphate formation in hepatocyte cell culture and/or suspension. In the same systems, prostaglandin E2 decreased the glucagon-stimulated (1 nM) glycogen-phosphorylase activity and cAMP formation. The signalling pathway leading to the glycogenolytic effect of PGE2 was interrupted by incubation of the hepatocytes with 4 beta-phorbol 12-myristate 13-acetate (100 nM) for 10 min, while the antiglycogenolytic effect of prostaglandin E2 was not attenuated. The signalling pathway leading to the antiglycogenolytic effect of prostaglandin E2 was interrupted by an incubation of cultured hepatocytes with pertussis toxin (100 ng/ml) for 18 h, whereas the glycogenolytic effect of prostaglandin E2 was enhanced. The EP1/EP3 prostaglandin-E2-receptor-specific prostaglandin E2 analogue Sulproston had a stronger glycogenolytic potency than the EP3 prostaglandin-E2-receptor-specific prostaglandin E2 analogue Misoprostol. The antiglycogenolytic potency of both agonists was equal. It is concluded that the glycogenolytic and the antiglycogenolytic effects of prostaglandin E2 are mediated via different signalling pathways in hepatocytes possibly involving EP1 and EP3 prostaglandin E2 receptors, respectively. PMID:8281925
Preparation of Complexes Containing TidE, Ti2(-E)2, and Ti(2-E2) (E ) O, S) Functionalities from a Reactive Titanium Dinitrogen Complex
Hagadorn, John R.
Preparation of Complexes Containing TidE, Ti2(µ-E)2, and Ti(2-E2) (E ) O, S) Functionalities from/Hg amalgam reduction of the Ti(IV) amidinate, L2TiCl2 (L ) PhC(NSiMe3)2).17 The putative Ti- (II) intermediate was trapped using N2 to give the dark blue dinitrogen complex, (L2Ti)2(µ-N2),16 in moderate yield
Estrogen in a karstic aquifer.
Wicks, Carol; Kelley, Cheryl; Peterson, Eric
Adverse impacts on the health of some fish populations, such as skewed sex distributions, have been noted in surface waters and in laboratory experiments with relatively low concentrations (above 25 ng/L) of natural estrogen (17 beta-estradiol--E2). Sources of E2 to surface and ground waters can include avian, human, and mammalian waste products. The Ozark Plateau Aquifer (OPA) is a karstic basin that receives a significant portion of its water through losing reaches of rivers. Thus, there is a direct connection between surface water and ground water. The OPA was targeted for an E2 study to assess the potential for adverse health effects to aquatic organisms living in the system. Eight springs, which drain the aquifer, were sampled quarterly. The concentrations of E2 in the OPA ranged from 13 to 80 ng/L. For any one sampling event, the concentrations of E2 at the spring waters were statistically similar; however, the concentrations of E2 at all springs varied throughout the year. At Maramec Spring, one of the larger springs, the E2 concentration, was correlated with discharge. Based on the correlation between discharge and E2 concentration, aquatic organisms living in the plateau or in its discharged waters, including the threatened southern cavefish T. subterraneus, are exposed to concentration of E2 above 25 ng/L approximately 60% of the time. This implies that organisms living in karst basins throughout the OPA are likely exposed to E2 concentrations that may adversely impact their reproductive success for a significant portion of each year. PMID:15161155
The recognition of local DNA conformation by the human papillomavirus type 6 E2 protein
Elizabeth Hooley; Victoria Fairweather; Anthony R. Clarke; Kevin Gaston; R. Leo Brady
The E2 proteins are transcription\\/replication factors from papillomaviruses. Human papillomaviruses (HPVs) can be broadly divided in two groups; low- risk HPV subtypes cause benign warts while high- risk HPVs give rise to cervical cancer. Although a range of crystal structures of E2 DNA-binding domains (DBD) from both high- and low-risk HPV subtypes have been reported previously, structures of E2 DBD:DNA
Expression Patterns of Retinoblastoma and E2F Family Proteins during Corneal Development
Claudia M. Francesconi; Audrey E. K. Hutcheon; Eui-Hong Chung; Ana C. Dalbone; Nancy C. Joyce; James D. Zieske
PURPOSE. To determine the expression patterns of the retinoblastoma protein and the E2F tran- scription factor families in limbal and corneal epithelia and in corneal keratocytes in situ during corneal development and differentiation. METHODS. Retinoblastoma protein (pRb) and its family members p107 and p130; E2F-1, -2, and -4, members of the E2F family of transcription factors; and Ki67, a marker
Interplay Between Cyclin-Dependent Kinases and E2F-Dependent Transcription
Jun-Yuan Ji; Nicholas J. Dyson
\\u000a Precise control of cell proliferation is essential for normal development and survival of all multi-cellular organisms. The\\u000a deregulation of cell proliferation is a fundamental feature of all types of cancer. One of the key regulators of cell proliferation\\u000a is the E2F transcription factor. E2F controls the expression of many genes that are required for cells to divide and elevated\\u000a E2F
Identification of novel 17\\\\-estradiol (E2) target genes using cross-experiment gene expression datasets
Won Cheol Yim; Changwon Keum; Saehwan Kim; Yeojeong Cho; Byung-Moo Lee; Yongeun Kwon
17?-estradiol (E2) is an environmental estrogen-like chemicals that is known to affect mainly reproductive functions of exposed\\u000a targets. Although microarray based toxicogenomics approach allows the investigation of the potential risks of E2 in DNA level,\\u000a the underling mechanisms related to their toxic effect is not fully understood. In this work, we identified genes responding\\u000a toE2 by analyzing cross-experiment public gene
TRANSCRIPTION: Chromatin Control--a Place for E2F and Myc to Meet
NSDL National Science Digital Library
Nicholas B. La Thangue (University of Glasgow; Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences)
Access to the article is free, however registration and sign-in are required. The transcription factor E2F switches on target genes during the early G1 phase of the cell cycle. In his Perspective, La Thangue discusses new findings (Ogawa et al.) that reveal the importance of an E2F family member, E2F-6, for silencing genes in quiescent cells in G0 of the cell cycle.
Polymorphic genetic characterization of E2 gene of bovine viral diarrhea virus in China.
Lang, Yifei; Gao, Shandian; Du, Junzheng; Shao, Junjun; Cong, Guozheng; Lin, Tong; Zhao, Furong; Liu, Lihong; Chang, Huiyun
Bovine viral diarrhea virus (BVDV) is one of the wide distributed pathogenic viruses of livestock and wild animals worldwide. E2 glycoprotein is a major structural component of the BVDV virion and plays a key role in viral attachment to host cells and inducing immune responses against viral infection. In order to gain detailed information of the E2 coding region of BVDV circulating in China, 46 positive samples were tested by RT-PCR for the E2 coding region. The 1122 nt nucleotide sequences of full-length E2 were harvested and analyzed. The results suggested that full-length E2 was an ideal target for BVDV genotyping and divided the domestic BVDV isolates into 9 subgenotypes, namely BVDV-1a, -1b1, -1c, -1d, -1o, -1m, -1p, -1q and BVDV-2a, showing great diversity. The difference of nonsynonymous and synonymous substitution rates (dN-dS) inferred both positive and purifying selection of the E2. However, combination of positive and purifying selection at different points indicated purifying selection within the complete E2. Protein properties analysis based on glycosylation sites and epitope prediction demonstrated that the biological character of E2 among individual BVDV subgenotype was similar, but may alter due to amino acid changes. For the first time, the comprehensive collection of E2 sequences of Chinese BVDV isolates was elucidated, which would provide information for future vaccine design and BVD control in China. PMID:25465669
Characterization of the nuclear localization signal of high risk HPV16 E2 protein
Klucevsek, Kristin [Biology Department, Boston College, Higgins Hall, room 578, 140 Commonwealth Avenue, Chestnut Hill, MA 02467 (United States); Wertz, Mary [Biology Department, Boston College, Higgins Hall, room 578, 140 Commonwealth Avenue, Chestnut Hill, MA 02467 (United States); Lucchi, John [Biology Department, Boston College, Higgins Hall, room 578, 140 Commonwealth Avenue, Chestnut Hill, MA 02467 (United States); Leszczynski, Anna [Biology Department, Boston College, Higgins Hall, room 578, 140 Commonwealth Avenue, Chestnut Hill, MA 02467 (United States); Moroianu, Junona [Biology Department, Boston College, Higgins Hall, room 578, 140 Commonwealth Avenue, Chestnut Hill, MA 02467 (United States)]. E-mail: email@example.com
The E2 protein of high risk human papillomavirus type 16 (HPV16) contains an amino-terminal (N) domain, a hinge (H) region and a carboxyl-terminal (C) DNA-binding domain. Using enhanced green fluorescent protein (EGFP) fusions with full length E2 and E2 domains in transfection assays in HeLa cells, we found that the C domain is responsible for the nuclear localization of E2 in vivo, whereas the N and H domains do not contain additional nuclear localization signals (NLSs). Deletion analysis of EGFP-E2 and EGFP-cE2 determined that the C domain contains an {alpha} helix cNLS that overlaps with the DNA-binding region. Mutational analysis revealed that the arginine and lysine residues in this cNLS are essential for nuclear localization of HPV16 E2. Interestingly, these basic amino acid residues are well conserved among the E2 proteins of BPV-1 and some high risk HPV types but not in the low risk HPV types, suggesting that there are differences between the NLSs and corresponding nuclear import pathways between these E2 proteins.
Characterization of the Nuclear Localization Signal of High Risk HPV16 E2 Protein
Klucevsek, Kristin; Wertz, Mary; Lucchi, John; Leszczynski, Anna; Moroianu, Junona
The E2 protein of high risk human papillomavirus type 16 (HPV16) contains an amino-terminal (N) domain, a hinge (H) region and a carboxyl-terminal (C) DNA binding domain. Using enhanced green fluorescent protein (EGFP) fusions with full length E2 and E2 domains in transfection assays in HeLa cells we found that the C domain is responsible for the nuclear localization of E2 in vivo, whereas the N and H domains do not contain additional nuclear localization signals (NLSs). Deletion analysis of EGFP-E2 and EGFP-cE2 determined that the C domain contains an alpha helix cNLS that overlaps with the DNA binding region. Mutational analysis revealed that the arginine and lysine residues in this cNLS are essential for nuclear localization of HPV16 E2. Interestingly, these basic amino acid residues are well conserved among the E2 proteins of BPV-1 and some high risk HPV types but not in the low risk HPV types, suggesting that there are differences between the NLSs and corresponding nuclear import pathways between these E2 proteins. PMID:17097712
Role for the p53 homologue p73 in E2F-1-induced apoptosis
Meredith Irwin; Maria Carmen Marin; Andrew C. Phillips; Ratnam S. Seelan; David I. Smith; Wanguo Liu; Elsa R. Flores; Kenneth Y. Tsai; Tyler Jacks; Karen H. Vousden; William G. Kaelin Jr.
The transcription factor E2F-1 induces both cell-cycle progression and, in certain settings, apoptosis. E2F-1 uses both p53-dependent and p53-independent pathways to kill cells. The p53-dependent pathway involves the induction by E2F-1 of the human tumour-suppressor protein p14ARF, which neutralizes HDM2 (human homologue of MDM2) and thereby stabilizes the p53 protein. Here we show that E2F-1 induces the transcription of the
Characterization and regulation of E2F activity during Caco-2 cell differentiation.
Ding, Q; Wang, Q; Dong, Z; Evers, B M
The specific mechanisms controlling intestinal cell differentiation remain largely undefined. The retinoblastoma (Rb) proteins (pRb, p130, and p107) appear crucial to the terminal differentiation process of certain cells through their association and repression of E2F transcription factors. We have examined the expression of pRb-related proteins p130 and p107 as well as the regulation of E2F during spontaneous differentiation of the Caco-2 intestinal cell line. Nuclear protein levels of p130 and p107 were increased with Caco-2 differentiation. Induction of a slower-migrating E2F complex was noted in postconfluent (i.e., differentiated) Caco-2 cells; p130 protein was the predominant component of this E2F complex with a minor contribution from cyclin-dependent kinase-2. A small component of p107 binding was identified by deoxycholate release gel shift assays. In contrast, no pRb binding to E2F was noted in Caco-2 cells. In addition to increased association with p130, E2F-4 phosphorylation was markedly decreased in differentiated Caco-2 cells, whereas E2F protein levels remained unchanged. Taken together, our findings suggest that the regulation of E2F function may be an important contributing factor in the cell cycle block and spontaneous differentiation of Caco-2 cells. This regulation of E2F occurs most likely through its increased association with p130 as well as decreased phosphorylation. PMID:10644518
Atypical E2fs Control Lymphangiogenesis through Transcriptional Regulation of Ccbe1 and Flt4
Weijts, Bart G. M. W.; van Impel, Andreas; Schulte-Merker, Stefan; de Bruin, Alain
Lymphatic vessels are derived from venous endothelial cells and their formation is governed by the Vascular endothelial growth factor C (VegfC)/Vegf receptor 3 (Vegfr3; Flt4) signaling pathway. Recent studies show that Collagen and Calcium Binding EGF domains 1 protein (Ccbe1) enhances VegfC-dependent lymphangiogenesis. Both Ccbe1 and Flt4 have been shown to be indispensable for lymphangiogenesis. However, how these essential players are transcriptionally regulated remains poorly understood. In the case of angiogenesis, atypical E2fs (E2f7 and E2f8) however have been recently shown to function as transcriptional activators for VegfA. Using a genome-wide approach we here identified both CCBE1 and FLT4 as direct targets of atypical E2Fs. E2F7/8 directly bind and stimulate the CCBE1 promoter, while recruitment of E2F7/8 inhibits the FLT4 promoter. Importantly, inactivation of e2f7/8 in zebrafish impaired venous sprouting and lymphangiogenesis with reduced ccbe1 expression and increased flt4 expression. Remarkably, over-expression of e2f7/8 rescued Ccbe1- and Flt4-dependent lymphangiogenesis phenotypes. Together these results identified E2f7/8 as novel in vivo transcriptional regulators of Ccbe1 and Flt4, both essential genes for venous sprouting and lymphangiogenesis. PMID:24069224
E2F-1:DP-1 induces p53 and overrides survival factors to trigger apoptosis.
Hiebert, S W; Packham, G; Strom, D K; Haffner, R; Oren, M; Zambetti, G; Cleveland, J L
The E2F DNA binding activity consists of a heterodimer between E2F and DP family proteins, and these interactions are required for association of E2F proteins with pRb and the pRb-related proteins p107 and p130, which modulate E2F transcriptional activities. E2F-1 expression is sufficient to release fibroblasts from G0 and induce entry into S phase, yet it also initiates apoptosis. To investigate the mechanisms of E2F-induced apoptosis, we utilized interleukin-3 (IL-3)-dependent 32D.3 myeloid cells, a model of hematopoietic progenitor programmed cell death. In the absence of IL-3, E2F-1 alone was sufficient to induce apoptosis, and p53 levels were diminished. DP-1 alone was not sufficient to induce cell cycle progression or alter rates of death following IL-3 withdrawal. However, overexpression of both E2F-1 and DP-1 led to the rapid death of cells even in the presence of survival factors. In the presence of IL-3, levels of endogenous wild-type p53 increased in response to E2F-1, and coexpression of DP-1 further augmented p53 levels. These results provide evidence that E2F is a functional link between the tumor suppressors p53 and pRb. However, induction of p53 alone was not sufficient to trigger apoptosis, suggesting that the ability of E2F to override survival factors involves additional effectors. PMID:8524253
E2F1 enhances glycolysis through suppressing Sirt6 transcription in cancer cells
Wu, Minghui; Seto, Edward; Zhang, Jingsong
The fast proliferation of cancer cells requires reprogramming of its energy metabolism with aerobic glycolysis as a major energy source. Sirt6, a class III histone deacetylase, has been shown to down regulate glycolysis by inhibiting the expression of several key glycolytic genes. Based on the published study on the metabolic phenotype of E2F1 ?/? mice and SIRT6 ?/? mice, we hypothesize that E2F1 enhances glycolysis and inhibits the expression of Sirt6. Indeed, over-expressing of E2F1, but not its DNA binding deficient mutant, significantly enhanced glucose uptake and lactate production in bladder and prostate cancer cell lines. E2F1 over-expression also suppressed Sirt6 expression and function. Moreover, E2F1 directly bound to Sirt6 promoter and suppressed Sirt6 promoter activity under both normoxic and hypoxic culture conditions. E2F1 siRNA blocked the up-regulation of E2F1 under hypoxia, increased Sirt6 expression and decreased glycolysis compared to those of scrambled siRNA transected cells. Furthermore, HDAC1 deacetylated E2F1 and diminished its transcription suppression of Sirt6 promoter. Treatment with the HDAC inhibitor, trichostatin A (TSA), suppressed Sirt6 promoter activity with increased binding of acetylated E2F1 to Sirt6 promoter. Mutating the E2F1 binding site on the proximal Sirt6 promoter abolished the suppression of Sirt6 transcription by TSA. These data indicate a novel oncogenic role of E2F1, i.e. enhancing glycolysis by suppressing Sirt6 transcription. PMID:25816777
Context-Dependent Requirement for dE2F during Oncogenic Proliferation
Nicolay, Brandon N.; Frolov, Maxim V.
The Hippo pathway negatively regulates the cell number in epithelial tissue. Upon its inactivation, an excess of cells is produced. These additional cells are generated from an increased rate of cell division, followed by inappropriate proliferation of cells that have failed to exit the cell cycle. We analyzed the consequence of inactivation of the entire E2F family of transcription factors in these two settings. In Drosophila, there is a single activator, dE2F1, and a single repressor, dE2F2, which act antagonistically to each other during development. While the loss of the activator dE2F1 results in a severe impairment in cell proliferation, this defect is rescued by the simultaneous loss of the repressor dE2F2, as cell proliferation occurs relatively normally in the absence of both dE2F proteins. We found that the combined inactivation of dE2F1 and dE2F2 had no significant effect on the increased rate of cell division of Hippo pathway mutant cells. In striking contrast, inappropriate proliferation of cells that failed to exit the cell cycle was efficiently blocked. Furthermore, our data suggest that such inappropriate proliferation was primarily dependent on the activator, de2f1, as loss of de2f2 was inconsequential. Consistently, Hippo pathway mutant cells had elevated E2F activity and induced dE2F1 expression at a point when wild-type cells normally exit the cell cycle. Thus, we uncovered a critical requirement for the dE2F family during inappropriate proliferation of Hippo pathway mutant cells. PMID:18833298
Structural models of the membrane anchors of envelope glycoproteins E1 and E2 from pestiviruses
Wang, Jimin; Li, Yue; Modis, Yorgo
The membrane anchors of viral envelope proteins play essential roles in cell entry. Recent crystal structures of the ectodomain of envelope protein E2 from a pestivirus suggest that E2 belongs to a novel structural class of membrane fusion machinery. Based on geometric constraints from the E2 structures, we generated atomic models of the E1 and E2 membrane anchors using computational approaches. The E1 anchor contains two amphipathic perimembrane helices and one transmembrane helix; the E2 anchor contains a short helical hairpin stabilized in the membrane by an arginine residue, similar to flaviviruses. A pair of histidine residues in the E2 ectodomain may participate in pH sensing. The proposed atomic models point to Cys987 in E2 as the site of disulfide bond linkage with E1 to form E1–E2 heterodimers. The membrane anchor models provide structural constraints for the disulfide bonding pattern and overall backbone conformation of the E1 ectodomain. PMID:24725935
COMMENTARY Open Access CDK4, pRB and E2F1: connected to insulin
Paris-Sud XI, Université de
COMMENTARY Open Access CDK4, pRB and E2F1: connected to insulin Lluis Fajas1,2,3,4* , Emilie involved in the control of glucose homeostasis. This particular cell type controls insulin secretion-induced insulin secretion in pancreatic b- cells. Expression of Kir6.2 is lost in pancreas of E2f1-/- mice
The CDK4-pRB-E2F1 pathway controls insulin secretion
Boyer, Edmond
The CDK4-pRB-E2F1 pathway controls insulin secretion Jean-Sébastien Annicotte1, 2, 7 , Emilie equally to this work Running title : E2F1 and insulin secretion inserm-00418907,version1-22Sep2009 Author in the regulation of glucose-induced insulin secretion. We demonstrate, by in tissue chromatin immunoprecipitation
Regulation of the Arf tumor suppressor by E2F transcription factors
Iaquinta, Phillip John
Effective tumor suppression requires the appropriate function of two major signaling pathways, the pRB-E2F growth-control pathway and the p53 stress-response pathway. Members of the E2F family of transcription factors are ...
Daxx inhibits muscle differentiation by repressing E2A-mediated transcription
Gupta, Amitabh; Hou, Rong; Liu, Liming; Hiroyasu, Shungo; Hadix, Jennifer A.; Huggins, Gordon S.; Sibinga, Nicholas E. S.
The basic helix-loop-helix (HLH) E2A transcription factors bind to DNA as homodimers or as heterodimers formed with other basic HLH factors, activate gene expression, and promote differentiation of muscle, lymphoid, neuronal, and other cell types. These E2A functions can be inhibited by the Id proteins, HLH factors that sequester E2A in non-DNA binding dimers. Here we describe the direct interaction of E2A with Daxx, a broadly expressed non-HLH protein previously associated with apoptosis and transcriptional repression. Daxx inhibits E2A function, but not via an Id-like mechanism; rather, it recruits histone deacetylase activity to E2A-dependent promoters. Increased Daxx expression during muscle differentiation inhibits E2A-dependent expression of key myogenic genes and reduces myotube formation, while decreased Daxx expression promotes myotube formation. These results identify a new mechanism for limiting E2A activity and establish a link between Daxx-mediated gene regulation and control of cellular differentiation. PMID:19308989
Complete Genome Sequence of the Autographa californica Multiple Nucleopolyhedrovirus Strain E2.
Maghodia, Ajay B; Jarvis, Donald L; Geisler, Christoph
Many vectors that are commonly used in the baculovirus/insect cell system (BICS) are derived from the Autographa californica multiple nucleopolyhedrovirus (AcMNPV) strain E2. To facilitate work with these vectors, we sequenced the E2 genome, compared it to that of the AcMNPV C6 strain, and found that they are very similar overall. PMID:25502662
Complete Genome Sequence of the Autographa californica Multiple Nucleopolyhedrovirus Strain E2
Maghodia, Ajay B.; Jarvis, Donald L.
Many vectors that are commonly used in the baculovirus/insect cell system (BICS) are derived from the Autographa californica multiple nucleopolyhedrovirus (AcMNPV) strain E2. To facilitate work with these vectors, we sequenced the E2 genome, compared it to that of the AcMNPV C6 strain, and found that they are very similar overall. PMID:25502662
THE MUON CONTENT OF EXTENSIVE AIR SHOWERS WITH E 2 x 10 17
HE 3.4-7 THE MUON CONTENT OF EXTENSIVE AIR SHOWERS WITH E 2 x 10 17 EV. G.L. Cassiday, R. Cooper, S and the Michigan muon array are operating in coincidence, simultaneously measuring the energy, depth of shower maximum, and muon content of high energy (E 2 x 10 17 eV) extensive air showers. We present
26 CFR 1.669(e)-2A - Illustration of the provisions of section 669.
Code of Federal Regulations, 2011 CFR
...Internal Revenue 8 2011-04-01 2011-04-01 false Illustration of the provisions of section 669. 1.669(e)-2A...Beginning Before January 1, 1969 § 1.669(e)-2A Illustration of the provisions of section 669. The application...
26 CFR 1.669(e)-2A - Illustration of the provisions of section 669.
Code of Federal Regulations, 2014 CFR
...Internal Revenue 8 2014-04-01 2014-04-01 false Illustration of the provisions of section 669. 1.669(e)-2A...Beginning Before January 1, 1969 § 1.669(e)-2A Illustration of the provisions of section 669. The application...
26 CFR 1.669(e)-2A - Illustration of the provisions of section 669.
Code of Federal Regulations, 2010 CFR
...Internal Revenue 8 2010-04-01 2010-04-01 false Illustration of the provisions of section 669. 1.669(e)-2A...Beginning Before January 1, 1969 § 1.669(e)-2A Illustration of the provisions of section 669. The application...
26 CFR 1.669(e)-2A - Illustration of the provisions of section 669.
Code of Federal Regulations, 2013 CFR
...Internal Revenue 8 2013-04-01 2013-04-01 false Illustration of the provisions of section 669. 1.669(e)-2A...Beginning Before January 1, 1969 § 1.669(e)-2A Illustration of the provisions of section 669. The application...
26 CFR 1.669(e)-2A - Illustration of the provisions of section 669.
Code of Federal Regulations, 2012 CFR
...Internal Revenue 8 2012-04-01 2012-04-01 false Illustration of the provisions of section 669. 1.669(e)-2A...Beginning Before January 1, 1969 § 1.669(e)-2A Illustration of the provisions of section 669. The application...
Potencies of estrogenic compounds in in vitro screening assays and in life cycle tests with zebrafish in vivo.
Segner, H; Navas, J M; Schäfers, C; Wenzel, A
The objective of this study was to compare the estrogenic potency of environmental estrogens at two testing tiers: at the initial level of in vitro screening assays, and at the level of definitive fish reproduction tests in vivo. The in vitro tests included a recombinant yeast estrogen receptor (ER) assay, a competitive radioreceptor assay using the hepatic ER of carp (Cyprinus carpio), and assays on vitellogenin induction in cultured hepatocytes of rainbow trout (Oncorhynchus mykiss) and carp. In vivo, full life cycle tests with zebrafish (Danio rerio) were performed, using fertilization success as estrogen-sensitive reproductive endpoint. The test compounds included the natural estrogen 17beta-estradiol (E2) (only applied in the in vitro assays); the synthetic estrogen ethynylestradiol (EE2); and two xenoestrogens, 4-tert-octylphenol (OP) and bisphenol A (BPA). Among the in vitro assays, differences were observed in the relative ranking of the test substances, and in the absolute sensitivity (EC50 values), although the interassay differences of EC50 values were within one order of magnitude. The in vivo activity of the test compounds was not accurately predicted by the in vitro assays, with respect to neither sensitivity nor ranking. The in vitro assays tended to overestimate the relative potency of the xenoestrogens; i.e. the ratio between the activity of the reference compound, EE2, and that of the test compound. The best prediction of the in vivo fish test results was obtained from the recombinant yeast assay. PMID:12651187
Estrogenic activity of chemicals for dental and similar use in vitro.
Hashimoto, Y; Moriguchi, Y; Oshima, H; Nishikawa, J; Nishihara, T; Nakamura, M
The estrogenic activities of chemicals for dental and similar use were tested by a reporter gene assay (yeast two-hybrid system) and an estrogen/estrogen receptor (ER-alpha) competition binding assay (fluorescence polarization system). Among the 10 chemicals [bisphenol-A (BPA), bis-2-hydroxypropyl methacrylate (Bis-GMA), triethylene glycol dimethacrylate (TEGDMA), methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA), dibutyl phthalate (DBP), n-butyl benzyl phthalate (BBP), n-butyl phthalyl n-butyl glycolate (BPBG), di-2-ethylhexyl phthalate (DEHP), and di-2-ethylhexyl adipate (DOA)], which were diluted with DMSO to concentrations ranging from 5 x 10(-7) to 5 x 10(-3) M, and 17beta-estradiol (E2) as a positive control, BPA and BBP showed estrogenic activity in these two assays, while the remaining eight chemicals did not at the concentrations tested. Additional data, together with in vivo and epidemiological examinations, are required. Such investigations should also provide information on the validity of these methods for testing the estrogenic activity of chemicals. PMID:15347996
Effect of photoperiod on endocrine profiles and vitellogenin expression in European eels Anguilla anguilla during artificially induced ovarian development.
Parmeggiani, A; Govoni, N; Zannoni, A; Di Biase, A; Sirri, R; Forni, M; Mandelli, M; Mordenti, O
The aim of this work was to determine the effects of dark and light conditions on the E2, testosterone and thyroid hormones levels and on the gene expression levels (vitellogenin 1, vitellogenin 2, and estradiol receptor one) in European eels (Anguilla anguilla) during ovarian development induced by increasing doses of carp pituitary extracts (CPEs). The subjects were divided into 2 groups: 14-hour light:10-hour dark (Light Group) and 24-hour darkness (Dark Group). All the eels received intramuscular injections with CPE at a dosage of 10 mg/kg body weight (BW) once a week for the first 3 weeks, 20 mg/kg BW fourth-sixth week, 30 mg/kg BW seventh-ninth week, and 40 mg/kg up to the end of the experiment (13th week). Vitellogenin and estradiol receptor expression levels did not show significant differences between the two housing conditions whereas in both groups vitellogenin mRNA increased starting from first CPE injection. Testosterone and 17-beta estradiol plasma levels were significantly greater in the Dark Group compared with the Light Group starting from the ninth and the 13th week, respectively. These results suggest that darkness could be a useful variable for standardizing gonadal maturation in eels kept in captivity. PMID:25459031
The anti-inflammatory activities of Tanshinone IIA, an active component of TCM, are mediated by estrogen receptor activation and inhibition of iNOS.
Fan, Guan-Wei; Gao, Xiu-Mei; Wang, Hong; Zhu, Yan; Zhang, Ju; Hu, Li-Min; Su, Yan-Fang; Kang, Li-Yuan; Zhang, Bo-Li
Tanshinone IIA (Tan IIA) is a major compound extracted from a traditional herbal medicine Salvia miltiorrhiza BUNGE, which is used to treat cardiovascular diseases, cerebrovascular diseases and postmenopausal syndrome. It has also been shown to possess anti-inflammatory activity. Since Tan IIA has a similar structure to that of 17beta-estradiol (E(2)), the present study was undertaken to characterize the estrogenic activity of Tan IIA and to demonstrate a functional role of this activity in RAW 264.7 cells. In transient transfection assay, Tan IIA (10 microM) increases ERE-luciferase activity in an estrogen receptor (ER) subtype-dependent manner when either ERalpha or ERbeta were co-expressed in Hela cells. In LPS-induced RAW 264.7 cells, Tan IIA exerts anti-inflammatory effects by inhibition of iNOS gene expression and NO production, as well as inhibition of inflammatory cytokine (IL-1beta, IL-6, and TNF-alpha) expression via ER-dependent pathway. Therefore, it could serve as a potential selective estrogen receptor modulator (SERM) to treat inflammation-associated neurodegenerative and cardiovascular diseases without increasing the risk of breast cancer. PMID:19429433
Therapeutic Effects of Oligonol, Acupuncture, and Quantum Light Therapy in Chronic Nonbacterial Prostatitis
Öztekin, ?lhan; Akdere, Hakan; Can, Nuray; Aktoz, Tevfik; Turan, Fatma Nesrin
This research aimed to compare anti-inflammatory effects of oligonol, acupuncture, and quantum light therapy in rat models of estrogen-induced prostatitis. Adult male Wistar albino rats were grouped as follows: Group I, control (n = 10); Group II, chronic prostatitis (n = 10); Group III, oligonol (n = 10); Group IV, acupuncture (n = 10); Group V, quantum (n = 10); Group VI, oligonol plus quantum (n = 10); Group VII, acupuncture plus oligonol (n = 10); Group VIII, quantum plus acupuncture (n = 10); and Group IX, acupuncture plus quantum plus oligonol (n = 10). Chronic prostatitis (CP) was induced by the administration of 17-beta-estradiol (E2) and dihydrotestosterone (DHT). Oligonol was given for 6 weeks at a dose of 60?mg/day. Acupuncture needles were inserted at CV 3/4 and bilaterally B 32/35 points with 1-hour manual stimulation. Quantum therapy was administered in 5-minute sessions three times weekly for 6 weeks. Lateral lobes of prostates were dissected for histopathologic evaluation. Although all of the treatment modalities tested in this study showed anti-inflammatory effects in the treatment of CP in male rats, a synergistic effect was observed for oligonol plus quantum light combination. Monotherapy with oligonol showed a superior anti-inflammatory efficacy as compared to quantum light and acupuncture monotherapies. PMID:26064171
Estrogenic effects of two derivatives of icariin on human breast cancer MCF-7 cells.
Ye, H Y; Lou, Y J
The aims of the present study were to determine the estrogenic activities of icariin (ICA) and its derivatives and their structure-estrogenic activity relationship. Therefore, icaritin (ICT) and desmethylicaritin (DICT) were derived from ICA. The estrogenic activities of ICA, ICT and DICT were examined by cell proliferation and progestogen receptor mRNA expression of estrogen-receptor-positive MCF-7 cells. Current studies exhibited that ICT and DICT both markedly enhanced the proliferation of MCF-7 cells; as compared to estradiol (100%), their relative proliferative effects (RPE) were 90% and 94%, respectively. Cell proliferation induced by ICT and DICT was completely antagonized by ICI182,780. ICT and DICT increased progestogen receptor (PR) at mRNA levels at 48 h after treatment, although the effects were not as prominent as 17beta-estradiol (E2). Those phenomena were not observed with ICA. Results demonstrate that ICT and DICT (nonconjugated forms) possess estrogen-like activity; however, ICA appears to have no estrogenicity in the MCF-7 cell line model in vitro. PMID:16323292
Development of in vivo and in vitro assays to evaluate the physiological effects of environmental estrogens in fish
Tremblay, L.; Yao, Z.; Kraak, G. Van Der [Univ. of Guelph, Ontario (Canada). Dept. of Zoology
There are many reports of environmental chemicals that may act as estrogens by binding to the nuclear 17-{beta} estradiol (E{sub 2}) receptor. Experiments were conducted to evaluate whether the plant sterol {beta}-sitosterol and the detergent nonylphenol interact with hepatic estrogen receptors in fish. These compounds are estrogenic in mammals and are found in treated industrial and municipal sewage waters and in pulp and paper mill effluents. Specific high affinity binding sites were characterized in rainbow trout. Nonylphenol and sitosterol were found to have relative affinities of 0.009 and 0.0001 compared to E{sub 2}. To determine if these compounds act as E{sub 2} agonists, their ability to induce estrogen dependent processes was monitored. Induction of estrogen receptors is a common E{sub 2} dependent effect. While other groups have shown in other systems that induction of hepatic E2 receptor levels was estrogen dependent, the authors found that E{sub 2} did not increase E{sub 2} binding in goldfish. However, using isolated goldfish hepatocytes cells, E{sub 2}, sitosterol and nonylphenol induced vitellogenin production. Current studies are aimed at evaluating the structure and activity relationships of these compounds responsible for causing E{sub 2} binding and vitellogenin inductions. Other means to evaluate E{sub 2} binding in goldfish liver are also being investigated.
An optical immunosensor for rapid vitellogenin detection in plasma from carp (Cyprinus carpio).
Bulukin, E; Meucci, V; Minunni, M; Pretti, C; Intorre, L; Soldani, G; Mascini, M
Vitellogenin (vtg) has proven to be a sensitive and simple biomarker for assessing exposure of fish to environmental estrogens. The aim of this work was to develop a rapid, in the order of minutes, screening method for the detection of fish vtg. The surface plasmon resonance technique (Biacore Xtrade mark) was coupled with immunodetection for the determination of fish vtg in plasma and mucus from carp (Cyprinus carpio). Monoclonal anti-vtg antibodies were linked on the sensor surface through chemical cross-linking via a capturing antibody. A simple regeneration process allowed the reuse of the sensor surface. Sensor optimisation was carried out using carp vtg. The developed immunosensor was tested with vtg spiked samples and with plasma and mucus from fish exposed to 17beta-estradiol (E2). Vitellogenin could be detected in the ppm range in buffer as well as in plasma and mucus. Good discrimination between control and exposed samples was obtained. The results were compared with ELISA and a correlation coefficient of R(2)=0.85 (n=9) between the two methods indicated that the immunochemical biosensor could be used for the analysis of vtg in fish plasma samples. The assay time was 20min hence allowing for rapid sample screening. PMID:19071687
Exploration of potential ligands against cancer-causing transcription factor E2F3.
Hussain, Muzammal; Javeed, Aqeel; Ashraf, Muhammad; Siddique, Samerene; Riaz, Amjad; Mukhtar, Muhammad Mahmood
The transcription factor-based therapeutic approaches are the mainstay of current anticancer drug design options to develop highly selective agents with novel modes of action. In this paper, a homology model of DNA-binding domain of transcription factor E2F3 was generated according to X-ray structure of E2F4. As a first step of our proposed project aspired towards exploration of highly selective potential E2F3 ligands, we performed structure-based virtual screening of ZINC 3D chemical database by using Dock Blaster server. Then 31 compounds, selected by filtration step, were docked against the prominent DNA binding site residues of E2F3 model. Two of them have shown a promising interaction with respect to binding poses. The aim is to propose new active ligands against neoplasias characterized by overexpression of E2F3 transcription factor. PMID:23009996
Structure of a Pestivirus Envelope Glycoprotein E2 Clarifies Its Role in Cell Entry
El Omari, Kamel; Iourin, Oleg; Harlos, Karl; Grimes, Jonathan M.; Stuart, David I.
Summary Enveloped viruses have developed various adroit mechanisms to invade their host cells. This process requires one or more viral envelope glycoprotein to achieve cell attachment and membrane fusion. Members of the Flaviviridae such as flaviviruses possess only one envelope glycoprotein, E, whereas pestiviruses and hepacivirus encode two glycoproteins, E1 and E2. Although E2 is involved in cell attachment, it has been unclear which protein is responsible for membrane fusion. We report the crystal structures of the homodimeric glycoprotein E2 from the pestivirus bovine viral diarrhea virus 1 (BVDV1) at both neutral and low pH. Unexpectedly, BVDV1 E2 does not have a class II fusion protein fold, and at low pH the N-terminal domain is disordered, similarly to the intermediate postfusion state of E2 from sindbis virus, an alphavirus. Our results suggest that the pestivirus and possibly the hepacivirus fusion machinery are unlike any previously observed. PMID:23273918
Isolation of cDNA encoding the human NF-E2 protein.
Chan, J Y; Han, X L; Kan, Y W
The human homolog of mouse NF-E2 was isolated from the K562 cell line and found to encode a member of the basic leucine-zipper family of DNA-binding regulatory proteins. The deduced amino acid sequence of the mouse and human proteins exhibited near identity. Comparison to the related protein, Nrf1, revealed significant homologies at isolated regions, particularly within the basic domain, suggesting that NF-E2 and Nrf1 are members of a distinct subfamily of basic leucine-zipper proteins that share similar DNA-binding properties. High levels of human NF-E2 mRNA were observed in human erythroleukemic cell lines examined. Extensive survey of human tissue samples found NF-E2 expression not limited to erythropoeitic organs. Expression in the colon and testis suggests that NF-E2 may participate in the regulation of genes other than globin. Images Fig. 1 Fig. 3 Fig. 5 PMID:8248255
HCV E2 core structures and mAbs: something is still missing.
Castelli, Matteo; Clementi, Nicola; Sautto, Giuseppe A; Pfaff, Jennifer; Kahle, Kristen M; Barnes, Trevor; Doranz, Benjamin J; Dal Peraro, Matteo; Clementi, Massimo; Burioni, Roberto; Mancini, Nicasio
The lack of structural information on hepatitis C virus (HCV) surface proteins has so far hampered the development of effective vaccines. Recently, two crystallographic structures have described the core portion (E2c) of E2 surface glycoprotein, the primary mediator of HCV entry. Despite the importance of these studies, the E2 overall structure is still unknown and, most importantly, several biochemical and functional studies are in disagreement with E2c structures. Here, the main literature will be discussed and an alternative disulfide bridge pattern will be proposed, based on unpublished human monoclonal antibody reactivity. A modeling strategy aiming at recapitulating the available structural and functional studies of E2 will also be proposed. PMID:25172800
Measurement of the optical dielectric function of monolayer transition-metal dichalcogenides: MoS2, Mo S e2 , WS2, and WS e2
NASA Astrophysics Data System (ADS)
Li, Yilei; Chernikov, Alexey; Zhang, Xian; Rigosi, Albert; Hill, Heather M.; van der Zande, Arend M.; Chenet, Daniel A.; Shih, En-Min; Hone, James; Heinz, Tony F.
We report a determination of the complex in-plane dielectric function of monolayers of four transition-metal dichalcogenides: Mo S2 , Mo S e2 , W S2 , and WS e2 , for photon energies from 1.5 to 3 eV. The results were obtained from reflection spectra using a Kramers-Kronig constrained variational analysis. From the dielectric functions, we obtain the absolute absorbance of the monolayers. We also provide a comparison of the dielectric function for the monolayers with the corresponding bulk materials.
Direct visualization of Agrobacterium-delivered VirE2 in recipient cells
Li, Xiaoyang; Yang, Qinghua; Tu, Haitao; Lim, Zijie; Pan, Shen Q
Agrobacterium tumefaciens is a natural genetic engineer widely used to deliver DNA into various recipients, including plant, yeast and fungal cells. The bacterium can transfer single-stranded DNA molecules (T–DNAs) and bacterial virulence proteins, including VirE2. However, neither the DNA nor the protein molecules have ever been directly visualized after the delivery. In this report, we adopted a split-GFP approach: the small GFP fragment (GFP11) was inserted into VirE2 at a permissive site to create the VirE2-GFP11 fusion, which was expressed in A. tumefaciens; and the large fragment (GFP1–10) was expressed in recipient cells. Upon delivery of VirE2-GFP11 into the recipient cells, GFP fluorescence signals were visualized. VirE2-GFP11 was functional like VirE2; the GFP fusion movement could indicate the trafficking of Agrobacterium-delivered VirE2. As the natural host, all plant cells seen under a microscope received the VirE2 protein in a leaf-infiltration assay; most of VirE2 moved at a speed of 1.3–3.1 ?m sec?1 in a nearly linear direction, suggesting an active trafficking process. Inside plant cells, VirE2-GFP formed filamentous structures of different lengths, even in the absence of T-DNA. As a non-natural host recipient, 51% of yeast cells received VirE2, which did not move inside yeast. All plant cells seen under a microscope transiently expressed the Agrobacterium-delivered transgene, but only 0.2% yeast cells expressed the transgene. This indicates that Agrobacterium is a more efficient vector for protein delivery than T-DNA transformation for a non-natural host recipient: VirE2 trafficking is a limiting factor for the genetic transformation of a non-natural host recipient. The split-GFP approach could enable the real-time visualization of VirE2 trafficking inside recipient cells. PMID:24299048
Enhanced osteoblast proliferation and collagen gene expression by estradiol
Ernest, M.; Schmid, Ch.; Froesch, E.R. (University Hospital of Zurich (Switzerland))
Estrogens play a crucial role in the development of postmenopausal osteoporosis. However, the mechanism by which estrogens exert their effects on bone is unknown. To examine possible direct effects of 17{beta}-estradiol on bone-forming cells, the authors used pure rat osteoblast-like cells in vitro as a model. Osteoblast-like cells prepared from calvaria of newborn rats were cultured serum-free in methylcellulose-containing medium for 21 days. Osteoblast-like cells proliferate selectively into clonally derived cell clusters of spherical morphorlogy. 17{beta}-Estradiol at concentrations of 0.1 nM and 1 nM enhanced osteoblast-like cell proliferation by 41% and 68% above vehicle-treated controls. The biologically inactive stereoisomer 17{alpha}-estradiol (same concentrations) had no effect. Moreover, the antiestrogen tamoxifen abolished the stimulation of osteoblast-like cell proliferation by 17{beta}-estradiol. After 21 days of culture, RNA was prepared and analyzed in a dot-hybridization assay for the abundance of pro{alpha}1(I) collagen mRNA. Steady-state mRNA levels were increased in cultures treated with 17{beta}-estradiol in a dose-dependent manner with maximal stimulation at 1 nM and 10 nM. At the same concentrations, the percentage of synthesized protein (labeled by ({sup 3}H)proline pulse) that was digestible by collagenase was increased, indicating that 17{beta}-estradiol acts as pretranslational levels to enhance synthesis of bone collagen. These data show that the osteoblast is a direct target for 17{beta}-estradiol.
Oncogenic ETS fusions deregulate E2F3 target genes in Ewing sarcoma and prostate cancer
Bilke, Sven; Schwentner, Raphaela; Yang, Fan; Kauer, Maximilian; Jug, Gunhild; Walker, Robert L.; Davis, Sean; Zhu, Yuelin J.; Pineda, Marbin; Meltzer, Paul S.; Kovar, Heinrich
Deregulated E2F transcription factor activity occurs in the vast majority of human tumors and has been solidly implicated in disturbances of cell cycle control, proliferation, and apoptosis. Aberrant E2F regulatory activity is often caused by impairment of control through pRB function, but little is known about the interplay of other oncoproteins with E2F. Here we show that ETS transcription factor fusions resulting from disease driving rearrangements in Ewing sarcoma (ES) and prostate cancer (PC) are one such class of oncoproteins. We performed an integrative study of genome-wide DNA-binding and transcription data in EWSR1/FLI1 expressing ES and TMPRSS2/ERG containing PC cells. Supported by promoter activity and mutation analyses, we demonstrate that a large fraction of E2F3 target genes are synergistically coregulated by these aberrant ETS proteins. We propose that the oncogenic effect of ETS fusion oncoproteins is in part mediated by the disruptive effect of the E2F–ETS interaction on cell cycle control. Additionally, a detailed analysis of the regulatory targets of the characteristic EWSR1/FLI1 fusion in ES identifies two functionally distinct gene sets. While synergistic regulation in concert with E2F in the promoter of target genes has a generally activating effect, EWSR1/FLI1 binding independent of E2F3 is predominantly associated with repressed differentiation genes. Thus, EWSR1/FLI1 appears to promote oncogenesis by simultaneously promoting cell proliferation and perturbing differentiation. PMID:23940108
Transcriptional activation of the senescence regulator Lsh by E2F1.
Niu, Jing; Chen, Tianda; Han, Limin; Wang, Pan; Li, Na; Tong, Tanjun
Lsh, a protein related to the SNF2 family of chromatin-remodeling ATPases, is a major epigenetic regulator that is essential for DNA methylation and histone acetylation at repetitive elements. Lsh represses endogenous p16(INK4a) expression by recruiting HDAC to the p16(INK4a) promoter, which in turn delays cell senescence. However, the molecular mechanisms that govern loss of Lsh expression during cellular senescence have yet to be elucidated. Here we investigate the transcriptional regulation of the human Lsh promoter. We find that the minimal Lsh promoter is located between positions -216 and -119 relative to the transcription start site, and contains two putative E2F binding sites. Ectopic E2F1 increases expression of Lsh at both transcriptional and translational levels. E2F1 physically interacts with the Lsh promoter by binding to each of the two putative binding sites and transactivates the Lsh promoter. E2F1 also induces Lsh protein expression and transactivates the Lsh promoter in 2BS cells. At the same time, E2F1-induced Lsh promoter activity is reduced in senescent cells compared to young cells. These results indicate that E2F1 plays a crucial role in transcriptional control of the human Lsh gene and the decrease of Lsh expression in senescent cells is related to the repression of E2F1. PMID:21453717
E2F-7 couples DNA damage-dependent transcription with the DNA repair process.
Zalmas, Lykourgos-Panagiotis; Coutts, Amanda S; Helleday, Thomas; La Thangue, Nicholas B
The cellular response to DNA damage, mediated by the DNA repair process, is essential in maintaining the integrity and stability of the genome. E2F-7 is an atypical member of the E2F family with a role in negatively regulating transcription and cell cycle progression under DNA damage. Surprisingly, we found that E2F-7 makes a transcription-independent contribution to the DNA repair process, which involves E2F-7 locating to and binding damaged DNA. Further, E2F-7 recruits CtBP and HDAC to the damaged DNA, altering the local chromatin environment of the DNA lesion. Importantly, the E2F-7 gene is a target for somatic mutation in human cancer and tumor-derived mutant alleles encode proteins with compromised transcription and DNA repair properties. Our results establish that E2F-7 participates in 2 closely linked processes, allowing it to directly couple the expression of genes involved in the DNA damage response with the DNA repair machinery, which has relevance in human malignancy. PMID:23974101
E2F-7 couples DNA damage-dependent transcription with the DNA repair process
Zalmas, Lykourgos-Panagiotis; Coutts, Amanda S; Helleday, Thomas; La Thangue, Nicholas B
The cellular response to DNA damage, mediated by the DNA repair process, is essential in maintaining the integrity and stability of the genome. E2F-7 is an atypical member of the E2F family with a role in negatively regulating transcription and cell cycle progression under DNA damage. Surprisingly, we found that E2F-7 makes a transcription-independent contribution to the DNA repair process, which involves E2F-7 locating to and binding damaged DNA. Further, E2F-7 recruits CtBP and HDAC to the damaged DNA, altering the local chromatin environment of the DNA lesion. Importantly, the E2F-7 gene is a target for somatic mutation in human cancer and tumor-derived mutant alleles encode proteins with compromised transcription and DNA repair properties. Our results establish that E2F-7 participates in 2 closely linked processes, allowing it to directly couple the expression of genes involved in the DNA damage response with the DNA repair machinery, which has relevance in human malignancy. PMID:23974101
Rendezvous with Toutatis from the Moon: The Chang'e-2 mission
NASA Astrophysics Data System (ADS)
Huang, J.; Tang, X.; Meng, L.
Chang'e-2 probe was the second lunar probe of China, with the main objectives to demonstrate some key features of the new lunar soft landing technology, and its applications to future exploration missions. After completing the planned mission successfully, Chang'e-2 flew away from the Moon and entered into the interplanetary space. Later, at a distance of 7 million km from the Earth, Chang'e-2 encountered asteroid (4179) Toutatis with a very close fly-by distance and obtained colorful images with a 3-m resolution. Given some surplus velocity increment as well as the promotion of autonomous flight ability and improvement of control, propulsion, and thermal systems in the initial design, Chang'e-2 had the capabilities necessary for escaping from the Moon. By taking advantage of the unique features of the Lagrangian point, the first close fly-by of asteroid Toutatis was realized despite the tight constraints of propellant allocation, spacecraft-Earth communication, and coordination of execution sequences. Chang'e-2 realized the Toutatis flyby with a km-level distance at closest approach. In the absence of direct measurement method, based on the principle of relative navigation and through the use of the sequence of target images, we calculated the rendezvous parameters such as relative distance and image resolution. With the help of these parameters, some fine and new scientific discoveries about the asteroid were obtained by techniques of optical measurements and image processing. Starting with an innovative design, followed by high-fidelity testing and demonstration, elaborative implementation, and optimal usage of residual propellant, Chang'e-2 has for the first time successfully explored the Moon, L2 point and an asteroid, while achieving the purpose of 'faster, better, cheaper'. What Chang'e-2 has accomplished was far beyond our expectations. *J. Huang is the chief designer (PI) of Chang'e-2 probe, planned Chang'e-2's multi-objective and multitasking exploration mission.
HPV-16 E2 physical status and molecular evolution in vivo in cervical carcinomas.
Kahla, Saloua; Kochbati, Lotfi; Chanoufi, Mohamed Badis; Maalej, Mongi; Oueslati, Ridha
A key event in the development of cervical carcinoma is the deregulated expression of high-risk human papillomavirus (HR-HPV) oncogenes, most commonly due to HPV integration into host DNA. Here we explored whether HPV-16 E2 gene integrity is a biomarker of progressive disease with oncogenes expression. HPV-16 genome disruption was assessed by amplification of the entire E2 gene, while mRNA expression patterns of the E1, E2, E6, and E7 genes were evaluated by reverse transcription PCR (RT-PCR). As expected, E2 disruption was significantly higher among patients with cervical cancers than subjects with benign lesions (p=0.02). The status of the E2 gene correlated with tumorogenesis, and seemed also to correlate with the stage of the carcinomas, since integrated HPV-16 DNA was frequently detected in patients with advanced cancer stages (75% of stage III vs 60% stages I and II). In bivariate analysis, the lesions' grade was most significantly associated with HPV-16 DNA disruption (p<0.05). In cervical carcinoma the deletion pattern involved more frequently the E2 gene rather than the E1 gene (62.5% vs 45.8%). The prevalence of the E6/E7 HPV-16 transcripts in cervical carcinoma specimens and in benign cervical lesions were detected with frequencies of, respectively, 91.6% and 45.4%. The mRNA levels of the HPV-16 E6/E7 genes were expressed at approximately the same levels in each physical state. We consistently observed that E6/E7 were absent or weakly detectable in the presence of E2. However, in the absence of E2 the levels of E6/E7 markedly increased (p<0.05). This study underscores the significance of investigating alternative mechanisms of E2 expression and oncogenes E6/E7 transcripts in vivo as biomarkers for disease severity in cervical carcinomas. PMID:24170557
Ectopic Expression of E2F1 Stimulates ?-Cell Proliferation and Function
Grouwels, Gael; Cai, Ying; Hoebeke, Inge; Leuckx, Gunter; Heremans, Yves; Ziebold, Ulrike; Stangé, Geert; Chintinne, Marie; Ling, Zhidong; Pipeleers, Daniel; Heimberg, Harry; Van de Casteele, Mark
OBJECTIVE Generating functional ?-cells by inducing their proliferation may provide new perspectives for cell therapy in diabetes. Transcription factor E2F1 controls G1- to S-phase transition during the cycling of many cell types and is required for pancreatic ?-cell growth and function. However, the consequences of overexpression of E2F1 in ?-cells are unknown. RESEARCH DESIGN AND METHODS The effects of E2F1 overexpression on ?-cell proliferation and function were analyzed in isolated rat ?-cells and in transgenic mice. RESULTS Adenovirus AdE2F1-mediated overexpression of E2F1 increased the proliferation of isolated primary rat ?-cells 20-fold but also enhanced ?-cell death. Coinfection with adenovirus AdAkt expressing a constitutively active form of Akt (protein kinase B) suppressed ?-cell death to control levels. At 48 h after infection, the total ?-cell number and insulin content were, respectively, 46 and 79% higher in AdE2F1+AdAkt-infected cultures compared with untreated. Conditional overexpression of E2F1 in mice resulted in a twofold increase of ?-cell proliferation and a 70% increase of pancreatic insulin content, but did not increase ?-cell mass. Glucose-challenged insulin release was increased, and the mice showed protection against toxin-induced diabetes. CONCLUSIONS Overexpression of E2F1, either in vitro or in vivo, can stimulate ?-cell proliferation activity. In vivo E2F1 expression significantly increases the insulin content and function of adult ?-cells, making it a strategic target for therapeutic manipulation of ?-cell function. PMID:20299467
Materials characterization activities for %E2%80%9CTake Our Sons&Daughters to Work Day%E2%80%9D 2013.
Mowry, Curtis Dale; Pimentel, Adam S.; Sparks, Elizabeth Schares; Hanlon, Brittany Paula
We created interactive demonstration activities for Take Our Daughters&Sons to Work Day (TODSTWD) 2013 in order to promote general interest in chemistry and also generate awareness of the type of work our laboratories can perform. %E2%80%9CCurious about Mars Rover Curiosity?%E2%80%9D performed an elemental analysis on rocks brought to our lab using the same technique utilized on the planet Mars by the NASA robotic explorer Curiosity. %E2%80%9CFood is Chemistry?%E2%80%9D utilized a mass spectrometer to measure, in seconds, each participant's breath in order to identify the food item consumed for the activity. A total of over 130 children participated in these activities over a 3 hour block, and feedback was positive. This document reports the materials (including handouts), experimental procedures, and lessons learned so that future demonstrations can benefit from the baseline work performed. We also present example results used to prepare the Food activity and example results collected during the Curiosity demo.
Expression of bovine viral diarrhoea virus glycoprotein E2 by bovine herpesvirus-1 from a synthetic ORF and incorporation of E2 into recombinant virions
Jutta Schmitt; Paul Becher; M. Keil
Expression cassettes containing the codons for the pestivirus E rns signal peptide (Sig) followed by a chemically synthesized ORF that encoded the bovine viral diarrhoea virus (BVDV) strain C86 glycoprotein E2, a class I membrane glycoprotein, were constructed with and without a chimeric intron sequence immediately upstream of the translation start codon, and incorporated into the genome of bovine herpesvirus-1
Finite dimensional representations of the Euclidean algebra e(2) having two generators
Douglas, Andrew [Department of Mathematics, University of Toronto, Toronto, Ontario, M5S 2E4 (Canada)
The Euclidean algebra e(2) is the Lie algebra of the group E(2) of Euclidean transformations of the plane. This paper examines finite dimensional representations of e(2) having two generators. To each representation with two generators we associate a graph. In term of graphs, we give a criterion for the indecomposability of such representations and describe an invariant for indecomposable representations. We also classify the indecomposable representations of dimensions 5 and 6, regardless of the number of generators (dimensions less than 5 have been classified). In each case there are finitely many such representations. Next, we show that for each dimension {>=}8 there are infinitely many nonequivalent indecomposable representations.
B(E2) Evaluation for 01+?21+ Transitions in Even-Even Nuclei
NASA Astrophysics Data System (ADS)
Pritychenko, B.; Birch, M.; Horoi, M.; Singh, B.
A collaborative study by Brookhaven-McMaster-Central Michigan is underway to evaluate B(E2)? for 01+?21+ transitions. This work is a continuation of a previous USNDP evaluation and has been motivated by a large number of recent measurements and nuclear theory developments. It includes an extended compilation, data evaluation procedures and shell model calculations. The subset of B(E2)? recommended values for nuclei of relevance to the double-beta decay problem is presented, and evaluation policies of experimental data and systematics are discussed. Future plans for completion of the B(E2;01+?21+) evaluation project are also described.
Regulation of E2F-1 gene expression in human breast cancer cells
Ngwenya, Sharon Khethiwe
with an expression plasmid containing the yeast GAL4 DNA binding domain fused to pM-NFYA and a construct containing five tandem GAL4 response elements. Subsequent studies showed that hormonal activation of pE2F-1jm1 and pM-NFYA are dependent on non...-genomic pathways in which E2 activates cAMP/protein kinase A. Hormone-dependent regulation of E2F-1 iv gene expression in ZR-75 and MCF-7 involves different mechanisms, demonstrating the importance of cell context on transactivation pathways, even among ER...
A Proposal for Integrated Efficacy-to-Effectiveness (E2E) Clinical Trials
Selker, H P
We propose an "efficacy-to-effectiveness" (E2E) clinical trial design, in which an effectiveness trial would commence seamlessly upon completion of the efficacy trial. Efficacy trials use inclusion/exclusion criteria to ...
40 CFR Figure E-2 to Subpart E of... - Product Manufacturing Checklist
Code of Federal Regulations, 2012 CFR
... Protection of Environment 6 2012-07-01 2012-07-01 false Product Manufacturing Checklist E Figure E-2 to Subpart E of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...
40 CFR Figure E-2 to Subpart E of... - Product Manufacturing Checklist
Code of Federal Regulations, 2014 CFR
... Protection of Environment 6 2014-07-01 2014-07-01 false Product Manufacturing Checklist E Figure E-2 to Subpart E of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...
40 CFR Figure E-2 to Subpart E of... - Product Manufacturing Checklist
Code of Federal Regulations, 2011 CFR
... Protection of Environment 5 2011-07-01 2011-07-01 false Product Manufacturing Checklist E Figure E-2 to Subpart E of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...
40 CFR Figure E-2 to Subpart E of... - Product Manufacturing Checklist
Code of Federal Regulations, 2010 CFR
... Protection of Environment 5 2010-07-01 2010-07-01 false Product Manufacturing Checklist E Figure E-2 to Subpart E of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...
40 CFR Figure E-2 to Subpart E of... - Product Manufacturing Checklist
Code of Federal Regulations, 2013 CFR
... Protection of Environment 6 2013-07-01 2013-07-01 false Product Manufacturing Checklist E Figure E-2 to Subpart E of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...
E2GK: Evidential Evolving Gustafsson-Kessel Algorithm For Data Streams Partitioning Using
Paris-Sud XI, Université de
E2GK: Evidential Evolving Gustafsson-Kessel Algorithm For Data Streams Partitioning Using Belief. The algorithm enables an online partitioning of data streams based on two existing and efficient algorithms
The role of E2F4 in the growth suppressive properties of the retinoblastoma protein
Lee, Eunice Y. (Eunice Yoon)
The growth suppressive functions of the retinoblastoma protein (pRB), the first identified tumor suppressor, are considerably mediated through the repression of the E2F transcription factors. Functional inactivation of ...
26 CFR 48.4216(e)-2 - Limitation on aggregate of exclusions and price readjustments.
Code of Federal Regulations, 2010 CFR
...2010-04-01 true Limitation on aggregate of exclusions and price readjustments...48.4216(e)-2 Limitation on aggregate of exclusions and price readjustments...contributions to a local advertising program in connection with which he makes...
Identification of New Functional Regions in Hepatitis C Virus Envelope Glycoprotein E2?
Albecka, Anna; Montserret, Roland; Krey, Thomas; Tarr, Alexander W.; Diesis, Eric; Ball, Jonathan K.; Descamps, Véronique; Duverlie, Gilles; Rey, Felix; Penin, François; Dubuisson, Jean
Little is known about the structure of the envelope glycoproteins of hepatitis C virus (HCV). To identify new regions essential for the function of these glycoproteins, we generated HCV pseudoparticles (HCVpp) containing HCV envelope glycoproteins, E1 and E2, from different genotypes in order to detect intergenotypic incompatibilities between these two proteins. Several genotype combinations were nonfunctional for HCV entry. Of interest, a combination of E1 from genotype 2a and E2 from genotype 1a was nonfunctional in the HCVpp system. We therefore used this nonfunctional complex and the recently described structural model of E2 to identify new functional regions in E2 by exchanging protein regions between these two genotypes. The functionality of these chimeric envelope proteins in the HCVpp system and/or the cell-cultured infectious virus (HCVcc) was analyzed. We showed that the intergenotypic variable region (IgVR), hypervariable region 2 (HVR2), and another segment in domain II play a role in E1E2 assembly. We also demonstrated intradomain interactions within domain I. Importantly, we also identified a segment (amino acids [aa] 705 to 715 [segment 705-715]) in the stem region of E2, which is essential for HCVcc entry. Circular dichroism and nuclear magnetic resonance structural analyses of the synthetic peptide E2-SC containing this segment revealed the presence of a central amphipathic helix, which likely folds upon membrane binding. Due to its location in the stem region, segment 705-715 is likely involved in the reorganization of the glycoprotein complexes taking place during the fusion process. In conclusion, our study highlights new functional and structural regions in HCV envelope glycoprotein E2. PMID:21147916
Mre11 Complex and DNA Replication: Linkage to E2F and Sites of DNA Synthesis
We show that the Mre11 complex associates with E2F family members via the Nbs1 N terminus. This asso- ciation and Nbs1 phosphorylation are correlated with S-phase checkpoint proficiency, whereas neither is suf- ficient individually for checkpoint activation. The Nbs1 E2F interaction occurred near the Epstein-Barr virus origin of replication as well as near a chromosomal replication origin in the c-myc
Anatomy of the Replication Origin of Plasmid ColE2-P9
Masaru Yagura; Shin-ya Nishio; Hideki Kurozumi; Cheng-fu Wang; Tateo Itoh
The plasmid ColE2-P9 origin is a 32-bp region which is specifically recognized by the plasmid-specified Rep protein to initiate DNA replication. We analyzed the structural and functional organization of the ColE2 origin by using various derivatives carrying deletions and single-base-pair substitutions. The origin may be divided into three subregions: subregion I, which is important for stable binding of the Rep
Mitotic Kinesin-Like Protein 2 Binds and Colocalizes with Papillomavirus E2 during Mitosis
Ting Yu; Yu-Cai Peng; Elliot J. Androphy
MKlp2 is a kinesin-like motor protein of the central mitotic spindle required for completion of cytokinesis. Papillomavirus E2 is a sequence specific DNA binding protein that regulates viral transcription and replica- tion and is responsible for partitioning viral episomes into daughter cells during cell division. We demonstrate that MKlp2 specifically associates with the E2 protein during mitosis. Using chromatin immunoprecipitation,
Mitogenic Sonic hedgehog signaling drives E2F1-dependent lipogenesis in progenitor cells and Medulloblastoma
Bhatia, Bobby; Hsieh, Michael; Kenney, Anna Marie; Nahlé, Zaher
Deregulation of the Rb/E2F tumor suppressor complex and aberrantion of Sonic hedgehog (Shh) signaling are documented across the spectrum of human malignancies. Exaggerated de novo lipid synthesis is also found in certain highly proliferative, aggressive tumors. Here, we show that in Shh-driven medulloblastomas, Rb is inactivated and E2F1 is up-regulated, promoting lipogenesis. Extensive lipid accumulation and elevated levels of the lipogenic enzyme FASN mark those tumors. In primary cerebellar granule neuron precursors (CGNPs), proposed Shh-associated medulloblastoma cells-of-origin, Shh signaling triggers E2F1 and FASN expression while suppressing fatty acid oxidation (FAO), in a Smoothened-dependent manner. In the developing cerebellum, E2F1 and FASN co-localize in proliferating CGNPs. In vivo and in vitro, E2F1 is required for FASN expression and CGNP proliferation, and E2F1 knockdown impairs Shh-mediated FAO inhibition. Pharmacologic blockade of Rb inactivation and/or lipogenesis inhibits CGNP proliferation, drives medulloblastoma cell death, and extends survival of medulloblastoma-bearing animals in vivo. These findings identify a novel mechanism through which Shh signaling links cell cycle progression to lipid synthesis, through E2F1-dependent regulation of lipogenic enzymes. These findings pertinent to the etiology of tumor metabolism also underscore the key role of the Shh?E2F1?FASN axis in regulating de novo lipid synthesis in cancers, and as such its value as a global therapeutic target in hedgehog-dependent and/or Rb-inactivated tumors. PMID:20890301
Activation of BPV-1 replication in vitro by the transcription factor E2
NASA Astrophysics Data System (ADS)
Yang, Liu; Li, Rong; Mohr, Ian J.; Clark, Robin; Botchan, Michael R.
Soluble extracts from uninfected murine cells supplemented with purified viral E1 and E2 proteins support the replication of exogenously added papilloma virus DNA. The E2 transactivator stimulates the binding of the E1 replication protein to the minimal origin of replication and activates DNA replication. These results support the concept that transcription factors have a direct role in the initiation of DNA replication in eukaryotes by participating in the assembly of a complex at the origin of replication.
Functional processing and secretion of Chikungunya virus E1 and E2 glycoproteins in insect cells
S. W. H. Metz; C. Geertsema; Byron E. Martina; Paulina Andrade; J. Heldens; Oers van M. M; R. W. Goldbach; J. M. Vlak; G. P. Pijlman
Background - Chikungunya virus (CHIKV) is a mosquito-borne, arthrogenic Alphavirus that causes large epidemics in Africa, South-East Asia and India. Recently, CHIKV has been transmitted to humans in Southern Europe by invading and now established Asian tiger mosquitoes. To study the processing of envelope proteins E1 and E2 and to develop a CHIKV subunit vaccine, C-terminally his-tagged E1 and E2
Functional processing and secretion of Chikungunya virus E1 and E2 glycoproteins in insect cells
S. W. Metz; C. Geertsema; B. E. E. Martina; P. Andrade; J. G. M. Heldens; Oers van M. M; J. M. Vlak; G. P. Pijlman
Background: Chikungunya virus (CHIKV) is a mosquito-borne, arthrogenic Alphavirus that causes large epidemics in Africa, South-East Asia and India. Recently, CHIKV has been transmitted to humans in Southern Europe by invading and now established Asian tiger mosquitoes. To study the processing of envelope proteins E1 and E2 and to develop a CHIKV subunit vaccine, C-terminally his-tagged E1 and E2 envelope
Inactivation of Rb and E2f8 Synergizes To Trigger Stressed DNA Replication during Erythroid Terminal Differentiation
Ghazaryan, Seda; Sy, Chandler; Hu, Tinghui; An, Xiuli; Mohandas, Narla; Fu, Haiqing; Aladjem, Mirit I.; Chang, Victor T.; Opavsky, Rene
Rb is critical for promoting cell cycle exit in cells undergoing terminal differentiation. Here we show that during erythroid terminal differentiation, Rb plays a previously unappreciated and unorthodox role in promoting DNA replication and cell cycle progression. Specifically, inactivation of Rb in erythroid cells led to stressed DNA replication, increased DNA damage, and impaired cell cycle progression, culminating in defective terminal differentiation and anemia. Importantly, all of these defects associated with Rb loss were exacerbated by the concomitant inactivation of E2f8. Gene expression profiling and chromatin immunoprecipitation (ChIP) revealed that Rb and E2F8 cosuppressed a large array of E2F target genes that are critical for DNA replication and cell cycle progression. Remarkably, inactivation of E2f2 rescued the erythropoietic defects resulting from Rb and E2f8 deficiencies. Interestingly, real-time quantitative PCR (qPCR) on E2F2 ChIPs indicated that inactivation of Rb and E2f8 synergizes to increase E2F2 binding to its target gene promoters. Taken together, we propose that Rb and E2F8 collaborate to promote DNA replication and erythroid terminal differentiation by preventing E2F2-mediated aberrant transcriptional activation through the ability of Rb to bind and sequester E2F2 and the ability of E2F8 to compete with E2F2 for E2f-binding sites on target gene promoters. PMID:24865965
Temperature Dependent E2 Raman Modes in the ZnCoO Ternary Alloy
NASA Technical Reports Server (NTRS)
Samanta, K.; Bhattacharya, P.; Katiyar, R. S.
The anharmonic properties of low and high frequency E2 modes of ZnO and Co doped ZnO were investigated using Raman scattering spectroscopy. We have determined the behavior of frequency, linewidths, and lifetime of E2 modes in the temperature range from 80 to 800 K. In the case of E2(high) mode the frequency shift towards the lower energy side was analyzed in light of the theory of anharmonic phonon-phonon interaction and thermal expansion of the lattice, and the linewidth behavior was analyzed in terms of anharmonic effect of three-phonon decay mechanism. But in the case of E2(low), the linewidth and frequency behaved practically harmonic with respect to temperature and independent of Co substitutions. It is found that the E2(high) phonon anharmonicity is higher for ZnCoO alloys than in pure ZnO and it increases with the compositional disorder. The low temperature lifetime of E2 phonon in ZnO, 1 % and 3% Co doped ZnO were found to be 1.S2, 1.74, and 1.54 ps, respectively.
miR-98 delays skeletal muscle differentiation by down-regulating E2F5.
Kropp, Jeremie; Degerny, Cindy; Morozova, Nadezda; Pontis, Julien; Harel-Bellan, Annick; Polesskaya, Anna
A genome-wide screen had previously shown that knocking down miR-98 and let-7g, two miRNAs of the let-7 family, leads to a dramatic increase in terminal myogenic differentiation. In the present paper, we report that a transcriptomic analysis of human myoblasts, where miR-98 was knocked down, revealed that approximately 240 genes were sensitive to miR-98 depletion. Among these potential targets of miR-98, we identified the transcriptional repressor E2F5 and showed that it is a direct target of miR-98. Knocking down simultaneously E2F5 and miR-98 almost fully restored normal differentiation, indicating that E2F5 is involved in the regulation of skeletal muscle differentiation. We subsequently show that E2F5 can bind to the promoters of two inhibitors of terminal muscle differentiation, ID1 (inhibitor of DNA binding 1) and HMOX1 (heme oxygenase 1), which decreases their expression in skeletal myoblasts. We conclude that miR-98 regulates muscle differentiation by altering the expression of the transcription factor E2F5 and, in turn, of multiple E2F5 targets. PMID:25422988
Transcriptional control of stem cell fate by E2Fs and pocket proteins
Julian, Lisa M.; Blais, Alexandre
E2F transcription factors and their regulatory partners, the pocket proteins (PPs), have emerged as essential regulators of stem cell fate control in a number of lineages. In mammals, this role extends from both pluripotent stem cells to those encompassing all embryonic germ layers, as well as extra-embryonic lineages. E2F/PP-mediated regulation of stem cell decisions is highly evolutionarily conserved, and is likely a pivotal biological mechanism underlying stem cell homeostasis. This has immense implications for organismal development, tissue maintenance, and regeneration. In this article, we discuss the roles of E2F factors and PPs in stem cell populations, focusing on mammalian systems. We discuss emerging findings that position the E2F and PP families as widespread and dynamic epigenetic regulators of cell fate decisions. Additionally, we focus on the ever expanding landscape of E2F/PP target genes, and explore the possibility that E2Fs are not simply regulators of general 'multi-purpose' cell fate genes but can execute tissue- and cell type-specific gene regulatory programs. PMID:25972892
Analysis of the papillomavirus E2 and bromodomain protein Brd4 interaction using bimolecular fluorescence complementation.
Helfer, Christine M; Wang, Ranran; You, Jianxin
The human papillomavirus (HPV) vaccines effectively protect against new infections of up to four HPV subtypes. However, these vaccines are not protective against many other clinically relevant HPV subtypes and are ineffective at treating established HPV infections. There is therefore a significant need for antiviral treatments for persistent HPV infections. A promising anti-HPV drug target is the interaction between the HPV E2 protein and cellular bromodomain-containing protein 4 (Brd4) since this protein complex mediates several processes important for the viral life cycle including viral genome maintenance, replication, and transcription. Using bimolecular fluorescence complementation (BiFC) technology, we demonstrate the E2 and Brd4 interaction on both interphase chromatin and mitotic chromosomes throughout mitosis. The E2-Brd4 BiFC was significantly diminished by mutating the Brd4 binding sites in E2 or by a dominant negative inhibitor of the E2-Brd4 interaction, demonstrating the potential of BiFC for identifying inhibitors of this important virus-host interaction. Importantly, when Brd4 was released from chromatin using the bromodomain inhibitor JQ1(+), the E2-Brd4 interacting complex relocated into foci that no longer associate with mitotic chromosomes, pointing to JQ1(+) as a promising antiviral inhibitor of HPV genome maintenance during HPV persistent infection. PMID:24205059
Differential effects of raloxifene, tamoxifen and fulvestrant on a murine mammary carcinoma.
Lamb, Caroline A; Helguero, Luisa A; Fabris, Victoria; Lucas, Colombo; Molinolo, Alfredo A; Lanari, Claudia
The purpose of this study was to evaluate the effect of the selective estrogen receptor modulators raloxifene and tamoxifen and of the pure antiestrogen fulvestrant on tumor growth and progesterone receptor (PR) expression in an experimental model of breast cancer. The effects of these compounds on cell proliferation were studied in primary cultures of a progestin-dependent mammary carcinoma tumor line, in the presence of medroxyprogesterone acetate (MPA) or 17-beta-estradiol (E2). In in vivo studies the tumor was inoculated subcutaneously in BALB/c female mice treated with 20 mg MPA depot. Raloxifene (12.5 mg/kg) or tamoxifen (5 mg/kg) were administered in daily doses or E2 silastic pellets (5 mg) were implanted. When the tumors reached about 25-50 mm2 MPA was removed in half of the animals. E2 induced complete tumor regressions, tamoxifen inhibited tumor growth in vivo while raloxifene disclosed proliferative effects in animals in which MPA had been removed. In vitro, E2 inhibited cell proliferation at concentrations higher than 10(-14)M. Raloxifene and fulvestrant, but not tamoxifen, partially reverted E2-induced inhibition. Fulvestrant and tamoxifen inhibited MPA-induced cell proliferation while raloxifene had a stimulatory effect. Tamoxifen and E2 increased, raloxifene induced no effect, and fulvestrant significantly decreased PR expression. In this study we provide evidence for differential effects of tamoxifen and raloxifene on experimental mammary tumors. Since raloxifene is under evaluation for use in breast cancer prevention, these results may have important clinical implications. PMID:12779079
Rat lung cancer induced by malathion and estrogen.
Echiburú-Chau, C; Calaf, G M
Lung cancer can originate from exposure to exogenous and endogenous environmental carcinogens. The use of organophosphorus insecticides has significantly increased in agricultural environments and in urban settings. There is evidence that estrogen can increase lung cancer risk in women. The aim of the present study was to analyze morphological and molecular alterations induced by malathion (M) and 17beta-estradiol (E2) in rat lung tissues. There were four groups: saline solution (control) (100 microg/100 g body weight; BW), M (22 mg/100 g BW), E2 (30 microg/100 gr BW) and combination of both. The animals were injected over a 5-day period and sacrificed 240 days after treatments and lung tissues were excised and analyzed for morphological alterations. Morphometric analysis indicated that M plus E2-treated animals showed a significantly (P<0.05) higher incidence of parenchyma with alveolar proliferative lesions (PAPL), preneoplastic lesions in bronchiolar epithelium (hyperplasia, metaplasia, carcinoma in situ and invasive carcinoma) and atypical lymphatic morphology (lymphatic cell aggregates; LCA) than M or E2 alone-treated and control animals after 240 days. Molecular biology studies indicated that c-ErbB2 and Rho-A had higher protein expression in M plus E2-treated animals in comparison to control and either M- or E-treated animals. In summary, the combination of M and E2 sharply induced pathological lesions in lung alveolar parenchyma, bronchiolar epithelia and lymphatic tissues, in comparison to control animals or in animals treated with either substance alone. These results indicated an increase in risk of rodent lung tumor formation by environmental and endogenous substances. PMID:18695892
Ozonation attenuates the steroidogenic disruptive effects of sediment free oil sands process water in the H295R cell line.
He, Yuhe; Wiseman, Steve B; Zhang, Xiaowei; Hecker, Markus; Jones, Paul D; El-Din, Mohamed Gamal; Martin, Jonathan W; Giesy, John P
There is concern regarding oil sands process water (OSPW) produced by the oil sands industry in Alberta, Canada. Little is known about the potential for OSPW, and naphthenic acids (NAs), which are the primary persistent and toxic constituents of OSPW, to affect endocrine systems. Although ozonation significantly reduces concentrations of NAs and OSPW toxicity, it was hypothesized that oxidation of OSPW might produce hydroxylated products with steroidogenic activity. Therefore, untreated and ozone treated OSPW were examined for effects on sex steroid production using the H295R Steroidogenesis Assay. Untreated OSPW significantly decreased testosterone (T) and increased 17beta-estradiol (E2) concentrations at OSPW dilutions greater or equal to 10-fold. This effect was mainly due to decreased E2 metabolism. Analysis of CYP19A (aromatase) mRNA abundance and enzyme activity suggested that induction of this enzyme activity may have also contributed to these effects. Reduction of parent NA concentrations by 24% or 85% decreased the effect of OSPW on E2 production. Although T production remained significantly reduced in cells exposed to ozone treated OSPW, the effect was diminished. Aromatase mRNA abundance and enzyme activity were significantly greater in cells exposed to ozone treated OSPW, however the magnitude was less than in cells exposed to untreated OSPW. No change of E2 metabolism was observed in cells exposed to ozone treated OSPW, which may account for recovery of E2 levels. The results indicate that OSPW exposure can decrease E2 and T production, but ozonation is an effective treatment to reduce NA concentrations in OSPW without increasing affects on steroidogenesis. PMID:20466405
Inhibitory effects of technical grade methoxychlor on development of neonatal male mouse reproductive organs.
Cooke, P S; Eroschenko, V P
Effects of technical grade methoxychlor (MX), an estrogenic insecticide, and 17 beta-estradiol (E2) were examined on serum testosterone (T) concentrations and growth and histology of neonatal male mouse reproductive organs. Male NIH/Swiss mice received i.p. injections daily from birth to Day 9 with one of the following: 10 micrograms E2 or 0.1 or 1.0 mg MX or sesame oil vehicle. The mice were killed on Day 10. MX or did not affect body weights or mortality. Serum T concentrations in control mice were 0.29 +/- 0.03 ng/ml; T concentrations in males treated with MX or E2 were reduced. The 1.0-mg dose of both MX and E2 significantly decreased DNA contents of the seminal vesicles (SV), bulbourethral glands (BUG), and ventral prostate (VP) compared to controls. In the same animals, DNA contents of testes, epididymides, and efferent ductules were not decreased. The lower dose of MX (0.1 mg) decreased DNA content of only BUG and SV. DNA content of the ductus deferens was not affected by any treatment. E2 and both doses of MX also decreased epithelial morphogenesis in the SV and BUG, and inhibited the onset of mucin production in BUG epithelium and smooth muscle differentiation in the ductus deferens. In summary, our results indicate that technical grade MX, at doses as low as 0.1 mg/day, and E2 inhibit neonatal male reproductive tract development and decrease serum T concentrations. PMID:2340338
Estrogenic compounds in seawater and sediment from Halifax Harbour, Nova Scotia, Canada.
Robinson, Brian J; Hui, Joseph P M; Soo, Evelyn C; Hellou, Jocelyne
Abstract-Samples of seawater and surface sediment were collected from seven locations around Halifax Harbour, Nova Scotia, Canada, and analyzed for the presence of the organic estrogenic contaminants, bisphenol A (BPA), 17beta-estradiol (E2), and 17alpha-ethinylestradiol (EE2). Samples were extracted using solid phase extraction (seawater) or sonication (sediments), followed by fractionation on a two-layer alumina/silica gel column prior to analysis by liquid chromatography-tandem mass spectrometry (LCMS/MS) with negative-ion electrospray ionization. Levels of the three compounds consistently ranked as BPA > E2 > EE2. The least potent compound and plasticizer BPA reached levels of up to 2.6 ng/L in seawater and 9.5 ng/g in sediments; the natural product E2 was detected at concentrations up to 0.57 ng/L and 0.86 ng/g; while the synthetic estrogen EE2 was in most cases below the method detection limit (0.14 ng/L and 0.28 ng/g). The highest levels were observed in the influent of a secondary treatment plant that discharges into the harbor, with concentrations of 32.4 ng/L for BPA and 5.3 ng/L for E2. Overall, the results indicate that these compounds readily associate with suspended particles rather than remaining in the soluble phase. Measurement of the octanol-water partition coefficient (log K(OW)) confirmed these results, with values of 3.41, 3.89, and 4.16 for BPA, E2, and EE2, respectively. Partitioning experiments using spiked field samples further confirmed these findings, with sorption directly related to sediment total organic content and following the order EE2 > E2 > BPA. PMID:18702564
Efficient priming against classical swine fever with a safe glycoprotein E2 expressing Orf virus recombinant (ORFV VrV-E2)
Heiner Voigt; Catherine Merant; Daniel Wienhold; Angelika Braun; Evelyne Hutet; Marie-Frédérique Le Potier; Armin Saalmüller; Eberhard Pfaff; Mathias Büttner
An increasing demand in livestock animal husbandry for intervention or emergency vaccination strategies requires a rapid onset of protection linked to prevention of infectious agent spread. Using the new recombinant parapoxvirus (PPV) Orf virus (ORFV) as a vaccine expressing the CSFV E2 glycoprotein we demonstrate that a single intra-muscular application confers solid protection. In the prime only concept, multi-site application
Structure-function analysis of hepatitis C virus envelope glycoproteins E1 and E2.
Nayak, Aparajita; Pattabiraman, Nagarajan; Fadra, Numrah; Goldman, Radoslav; Kosakovsky Pond, Sergei L; Mazumder, Raja
Hepatitis C virus (HCV) is the leading cause of chronic liver disease in humans. The envelope proteins of HCV are potential candidates for vaccine development. The absence of three-dimensional (3D) structures for the functional domain of HCV envelope proteins [E1.E2] monomer complex has hindered overall understanding of the virus infection, and also structure-based drug design initiatives. In this study, we report a 3D model containing both E1 and E2 proteins of HCV using the recently published structure of the core domain of HCV E2 and the functional part of E1, and investigate immunogenic implications of the model. HCV [E1.E2] molecule is modeled by using aa205-319 of E1 to aa421-716 of E2. Published experimental data were used to further refine the [E1.E2] model. Based on the model, we predict 77 exposed residues and several antigenic sites within the [E1.E2] that could serve as vaccine epitopes. This study identifies eight peptides which have antigenic propensity and have two or more sequentially exposed amino acids and 12 singular sites are under negative selection pressure that can serve as vaccine or therapeutic targets. Our special interest is 285FLVGQLFTFSPRRHW299 which has five negatively selected sites (L286, V287, G288, T292, and G303) with three of them sequential and four amino acids exposed (F285, L286, T292, and R296). This peptide in the E1 protein maps to dengue envelope vaccine target identified previously by our group. Our model provides for the first time an overall view of both the HCV envelope proteins thereby allowing researchers explore structure-based drug design approaches. PMID:25245635
A genetic screen for modifiers of E2F in Drosophila melanogaster.
Staehling-Hampton, K; Ciampa, P J; Brook, A; Dyson, N
The activity of the E2F transcription factor is regulated in part by pRB, the protein product of the retinoblastoma tumor suppressor gene. Studies of tumor cells show that the p16(ink4a)/cdk4/cyclin D/pRB pathway is mutated in most forms of cancer, suggesting that the deregulation of E2F, and hence the cell cycle, is a common event in tumorigenesis. Extragenic mutations that enhance or suppress E2F activity are likely to alter cell-cycle control and may play a role in tumorigenesis. We used an E2F overexpression phenotype in the Drosophila eye to screen for modifiers of E2F activity. Coexpression of dE2F and its heterodimeric partner dDP in the fly eye induces S phases and cell death. We isolated 33 enhancer mutations of this phenotype by EMS and X-ray mutagenesis and by screening a deficiency library collection. The majority of these mutations sorted into six complementation groups, five of which have been identified as alleles of brahma (brm), moira (mor) osa, pointed (pnt), and polycephalon (poc). osa, brm, and mor encode proteins with homology to SWI1, SWI2, and SWI3, respectively, suggesting that the activity of a SWI/SNF chromatin-remodeling complex has an important impact on E2F-dependent phenotypes. Mutations in poc also suppress phenotypes caused by p21(CIP1) expression, indicating an important role for polycephalon in cell-cycle control. PMID:10471712
Characterization of Hepatitis C Virus Recombinants with Chimeric E1/E2 Envelope Proteins and Identification of Single Amino Acids in the E2 Stem Region Important for Entry
Carlsen, Thomas H. R.; Scheel, Troels K. H.; Ramirez, Santseharay; Foung, Steven K. H.
The hepatitis C virus (HCV) envelope proteins E1 and E2 play a key role in host cell entry and represent important targets for vaccine and drug development. Here, we characterized HCV recombinants with chimeric E1/E2 complexes in vitro. Using genotype 1a/2a JFH1-based recombinants expressing 1a core-NS2, we exchanged E2 with functional isolate sequences of genotypes 1a (alternative isolate), 1b, and 2a. While the 1a-E2 exchange did not impact virus viability, the 2a-E2 recombinant was nonviable. After E2 exchange from three 1b isolates, long delays were observed before spread of infection. For recovered 1b-E2 recombinants, single E2 stem region amino acid changes were identified at residues 706, 707, and 710. In reverse genetic studies, these mutations increased infectivity titers by ?100-fold, apparently without influencing particle stability or cell binding although introducing slight decrease in particle density. In addition, the 1b-E2 exchange led to a decrease in secreted core protein of 25 to 50%, which was further reduced by the E2 stem region mutations. These findings indicated that compensatory mutations permitted robust infectious virus production, without increasing assembly/release. Studies of E1/E2 heterodimerization showed no differences in intracellular E1/E2 interaction for chimeric constructs with or without E2 stem region mutations. Interestingly, the E2 stem region mutations allowed efficient entry, which was verified in 1a-E1/1b-E2 HCV pseudoparticle assays. A CD81 inhibition assay indicated that the mutations influenced a late step of the HCV entry pathway. Overall, this study identified specific amino acids in the E2 stem region of importance for HCV entry and for production of infectious virus particles. PMID:23152512
E2F-1 overexpression inhibits human gastric cancer MGC-803 cell growth in vivo
Wei, Wei-Yuan; Yan, Lin-Hai; Wang, Xiao-Tong; Li, Lei; Cao, Wen-Long; Zhang, Xiao-Shi; Zhan, Ze-Xu; Yu, Han; Xie, Yu-Bo; Xiao, Qiang
AIM: To evaluate the influence of E2F-1 on the growth of human gastric cancer (GC) cells in vivo and the mechanism involved. METHODS: E2F-1 recombinant lentiviral vectors were injected into xenograft tumors of MGC-803 cells in nude mice, and then tumor growth was investigated. Overexpression of transcription factor E2F-1 was assessed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting analysis. Apoptosis rates were determined using a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay. Expression levels of certain cell cycle regulators and apoptosis-related proteins, such as Bax, survivin, Bcl-2, cyclin D1, S-phase kinase-associated protein 2, and c-Myc were examined by Western blotting and RT-PCR. RESULTS: Xenograft tumors of MGC-803 cells in nude mice injected with E2F-1 recombinant lentiviral vectors stably overexpressed the E2F-1 gene as measured by semi-quantitative RT-PCR (relative mRNA expression: 0.10 ± 0.02 vs 0.05 ± 0.02 for control vector and 0.06 ± 0.03 for no infection; both P < 0.01) and Western blotting (relative protein expression: 1.90 ± 0.05 vs 1.10 ± 0.03 in control vector infected and 1.11 ± 0.02 for no infection; both P < 0.01). The growth-curve of tumor volumes revealed that infection with E2F-1 recombinant lentiviral vectors significantly inhibited the growth of human GC xenografts (2.81 ± 1.02 vs 6.18 ± 1.15 in control vector infected and 5.87 ± 1.23 with no infection; both P < 0.05) at 15 d after treatment. TUNEL analysis demonstrated that E2F-1 overexpression promoted tumor cell apoptosis (18.6% ± 2.3% vs 6.7% ± 1.2% in control vector infected 6.3% ± 1.2% for no infection; both P < 0.05). Furthermore, lentiviral vector-mediated E2F-1 overexpression increased the expression of Bax and suppressed survivin, Bcl-2, cyclin D1, Skp2, and c-Myc expression in tumor tissue. CONCLUSION: E2F-1 inhibits growth of GC cells via regulating multiple signaling pathways, and may play an important role in targeted therapy for GC. PMID:25593464
Analysis of murine B-cell epitopes on Eastern equine encephalitis virus glycoprotein E2.
EnCheng, Sun; Jing, Zhao; Tao, Yang; QingYuan, Xu; Yongli, Qin; WenShi, Wang; Peng, Wei; Liang, Sun; Jing, Sun; DongLai, Wu
The Eastern equine encephalitis virus (EEEV) E2 protein is one of the main targets of the protective immune response against EEEV. Although some efforts have done to elaborate the structure and immune molecular basis of Alphaviruses E2 protein, the published data of EEEV E2 are limited. Preparation of EEEV E2 protein-specific antibodies and define MAbs-binding epitopes on E2 protein will be conductive to the antibody-based prophylactic and therapeutic and to the study on structure and function of EEEV E2 protein. In this study, 51 EEEV E2 protein-reactive monoclonal antibodies (MAbs) and antisera (polyclonal antibodies, PAbs) were prepared and characterized. By pepscan with MAbs and PAbs using enzyme-linked immunosorbent assay, we defined 18 murine linear B-cell epitopes. Seven peptide epitopes were recognized by both MAbs and PAbs, nine epitopes were only recognized by PAbs, and two epitopes were only recognized by MAbs. Among the epitopes recognized by MAbs, seven epitopes were found only in EEEV and two epitopes were found both in EEEV and Venezuelan equine encephalitis virus (VEEV). Four of the EEEV antigenic complex-specific epitopes were commonly held by EEEV subtypes I/II/III/IV (1-16aa, 248-259aa, 271-286aa, 321-336aa probably located in E2 domain A, domain B, domain C, domain C, respectively). The remaining three epitopes were EEEV type-specific epitopes: a subtype I-specific epitope at amino acids 108-119 (domain A), a subtype I/IV-specific epitope at amino acids 211-226 (domain B) and a subtype I/II/III-specific epitope at amino acids 231-246 (domain B). The two common epitopes of EEEV and VEEV were located at amino acids 131-146 and 241-256 (domain B). The generation of EEEV E2-specific MAbs with defined specificities and binding epitopes will inform the development of differential diagnostic approaches and structure study for EEEV and associated alphaviruses. PMID:23512478
E2F1-Mediated Induction of NFYB Attenuates Apoptosis via Joint Regulation of a Pro-Survival Transcriptional Program
Jiang, Xiaolei; Nevins, Joseph Roy
The E2F1 transcription factor regulates cell proliferation and apoptosis through the control of a considerable variety of target genes. Previous work has detailed the role of other transcription factors in mediating the specificity of E2F function. Here we identify the NF-YB transcription factor as a novel direct E2F1 target. Genome-wide expression analysis of the effects of NFYB knockdown on E2F1-mediated transcription identified a large group of genes that are co-regulated by E2F1 and NFYB. We also provide evidence that knockdown of NFYB enhances E2F1-induced apoptosis, suggesting a pro-survival function of the NFYB/E2F1 joint transcriptional program. Bioinformatic analysis suggests that deregulation of these NFY-dependent E2F1 target genes might play a role in sarcomagenesis as well as drug resistance. PMID:26039627
Testing estrogenicity of known and novel (xeno-)estrogens in the MolDarT using developing zebrafish (Danio rerio).
Muncke, Jane; Junghans, Marion; Eggen, Rik I L
The MolDarT is a novel short-term assay for testing mechanism-based molecular effects in developing zebrafish embryos. The objective of this study was to evaluate the inducibility of vitellogenin1 mRNA (Vtg1) by the estrogenically active compounds 17beta-Estradiol (E2), 17alpha-Ethinylestradiol (EE2), Nonylphenol (NP), Bisphenol A (BPA), Cyproconazol, and the suspected xeno-estrogen Atrazin in the MolDarT. Freshly fertilized zebrafish eggs were exposed semistatically for 120 h. Using reverse transcription real-time PCR, the relative abundance of Vtg1 was measured. For EE2 a dose-response relationship was established with EC50 = 60.7 ng/L (205 pM). Induction of Vtg1 was significant at concentrations of 84 pM EE2 (25 ng EE2/L) and above, 10 nM E2 (2.7 microg E2/L), 100 nM E2 (27 microg E2/L), 10 microM BPA (2280 microg BPA/L), and 15 microM BPA (3420 microg BPA/L). At NP concentrations of 0.75 microM (165 microg NP/L) and 1.5 microM (330 microg NP/L) Vtg1 was significantly down-regulated. Both atrazine and cyproconazol showed no effect on relative Vtg1 abundance. With this study we further characterize the MolDarT assay and show its applicability for effect screening of compounds. PMID:17366571
Ovarian steroid hormone-regulated uterine remodeling occurs independently of macrophages in mice.
Care, Alison S; Ingman, Wendy V; Moldenhauer, Lachlan M; Jasper, Melinda J; Robertson, Sarah A
Macrophages are abundant in the uterine stroma and are intimately juxtaposed with other cell lineages comprising the uterine epithelial and stromal compartments. We postulated that macrophages may participate in mediating or amplifying the effects of ovarian steroid hormones to facilitate the uterine remodeling that is a characteristic feature of every estrus cycle and is essential for pregnancy. Using the Cd11b-Dtr transgenic mouse model with an ovariectomy and hormone replacement strategy, we depleted macrophages to determine their role in hormone-driven proliferation of uterine epithelial and stromal cells and uterine vascular development. Following diphtheria toxin (DT) administration, approximately 85% of EMR1-positive (EMR1?) macrophages, as well as 70% of CD11C? dendritic cells, were depleted from Cd11b-Dtr mice. There was no change in bromodeoxyuridine incorporation into epithelial cells induced to proliferate by administration of 17beta-estradiol (E2) to ovariectomized mice or into stromal cells induced to proliferate in response to E2 and progesterone (P4), and the resulting sizes and structures of the luminal epithelial and stromal cell compartments were not altered compared with those of leukocyte replete controls. Depletion of CD11B? myeloid cells failed to alter the density or pattern of distribution of uterine blood vessels, as identified by staining PECAM1-positive endothelial cells in the uterine stroma of E2- or E2 combined with P4 (E2P4)-treated ovariectomized mice. These experiments support the interpretation that macrophages are dispensable to regulation of proliferative events induced by steroid hormones in the cycling and early pregnant mouse uterus to establish the epithelial, stromal, and vascular architecture which is critical for normal reproductive competence. PMID:25061095
Gene expression analysis during tumor enhancement by the dietary phytochemical, 3,3'-diindolylmethane, in rainbow trout.
Tilton, Susan C; Hendricks, Jerry D; Orner, Gayle A; Pereira, Cliff B; Bailey, George S; Williams, David E
Indole-3-carbinol (I3C) and 3,3'-diindolylmethane (DIM), a primary I3C derivative, are known dietary chemopreventive agents also available as supplements. However, I3C has been found to act as a tumor promoter in rat (multi-organ) and trout (liver) models. I3C and DIM were previously found to be estrogenic in trout liver based on toxicogenomic profiles. In this study, we compare the post-initiation effects of DIM and 17beta-estradiol (E2) on aflatoxin B(1) (AFB(1))-induced hepatocarcinogenesis in trout. Trout were initiated as embryos with AFB(1) and juvenile fish were fed diets containing 0, 120 or 400 p.p.m. DIM or 5 p.p.m. E2 for 18 weeks. Tumor incidence was determined at 13 months and found to be significantly elevated in AFB(1)-initiated trout fed either 400 p.p.m. DIM or 5 p.p.m. E2 compared with control animals. To evaluate the mechanism of tumor enhancement, hepatic gene expression profiles were examined in animals fed promotional diets during the course of tumorigenesis and in hepatocellular carcinomas (HCCs) of initiated animals. We demonstrate that DIM alters gene expression profiles similar to E2 in liver samples during tumorigenesis and in HCC tumors. Further, HCCs from animals on DIM and E2 promotional diets had a transcriptional signature indicating decreased invasive or metastatic potential compared with HCCs from control animals. Overall, these findings are the first to demonstrate tumor promotion by DIM. They confirm the importance of estrogenic signaling in the mechanism of promotion by dietary indoles in trout liver and indicate a possible dual effect that enhances tumor incidence and decreases potential for metastasis. PMID:17272308
Estrogen-like response to p-nonylphenol in human first trimester placenta and BeWo choriocarcinoma cells.
Bechi, Nicoletta; Ietta, Francesca; Romagnoli, Roberta; Focardi, Silvano; Corsi, Ilaria; Buffi, Carlo; Paulesu, Luana
p-Nonylphenol (p-NP) is a metabolite of alkylphenol ethoxylates used as surfactants in the manufacturing industry. Although it is reported to have estrogenic activity and to be transferred from the mother to the embryo, no data are available on its effects on the development of the human placenta. In the present study, we investigated estrogen receptors' (ERs) expression in the first trimester human placenta. Using an in vitro model of chorionic villous explants, we then compared the effects of p-NP and 17beta-estradiol (17beta-E2). Finally, a trophoblast-derived choriocarcinoma cell line, BeWo, was used as a model of trophoblast cell differentiation. Our results showed that the first trimester placenta expresses three ER-alpha isoforms of 67, 46, and 39 kDa and one ER-beta isoform of 55 kDa. Immunohistochemistry revealed the expression of ER-alpha in the villous cytotrophoblast, whereas ER-beta was mainly expressed by the syncytiotrophoblast. Treatment of explant cultures with p-NP (10(-9)M) and 17beta-E2 (10(-9)M) significantly increased beta-hCG secretion and cell apoptosis but did not modify ER expression. After 72 h of exposure, hormone release was significantly higher in p-NP- than 17beta-E2-treated explant cultures. By this time, cleavage of caspase-3 was evident in cultures treated with 17beta-E2 and p-NP. In BeWo cells, a caspase-3 band of 20-16 kDa was evident after 1 h of treatment with p-NP and after 24 h of treatment with 17beta-E2 or forskolin. These findings suggest that the human trophoblast may be highly responsive to p-NP and raise concern about maternal exposure in early gestation. PMID:16790488
Anomalous DNA binding by E2 regulatory protein driven by spacer sequence TATA.
Xi, Zhiqun; Zhang, Yongli; Hegde, Rashmi S; Shakked, Zippora; Crothers, Donald M
We have investigated the anomalously weak binding of human papillomavirus (HPV) regulatory protein E2 to a DNA target containing the spacer sequence TATA. Experiments in magnesium (Mg(2+)) and calcium (Ca(2+)) ion buffers revealed a marked reduction in cutting by DNase I at the CpG sequence in the protein-binding site 3' to the TATA spacer sequence, Studies of the cation dependence of DNA-E2 affinities showed that upon E2 binding the TATA sequence releases approximately twice as many Mg(2+) ions as the average of the other spacer sequences. Binding experiments for TATA spacer relative to ATAT showed that in potassium ion (K(+)) the E2 affinity of the two sequences is nearly equal, but the relative dissociation constant (K(d)) for TATA increases in the order K(+ )< Na(+ )< Ca(2+ )< Mg(2+). Except for Mg(2+), K(d) for TATA relative to ATAT is independent of ion concentration, whereas for Mg(2+) the affinity for TATA drops sharply as ion concentration increases. Thus, ions of increasing positive charge density increasingly distort the E2 binding site, weakening the affinity for protein. In the case of Mg(2+), additional ions are bound to TATA that require displacement for protein binding. We suggest that the TATA sequence may bias the DNA structure towards a conformation that binds the protein relatively weakly. PMID:20185566
The Cellular Bromodomain Protein Brd4 has Multiple Functions in E2-Mediated Papillomavirus Transcription Activation
Helfer, Christine M.; Yan, Junpeng; You, Jianxin
The cellular bromodomain protein Brd4 functions in multiple processes of the papillomavirus life cycle, including viral replication, genome maintenance, and gene transcription through its interaction with the viral protein, E2. However, the mechanisms by which E2 and Brd4 activate viral transcription are still not completely understood. In this study, we show that recruitment of positive transcription elongation factor b (P-TEFb), a functional interaction partner of Brd4 in transcription activation, is important for E2's transcription activation activity. Furthermore, chromatin immunoprecipitation (ChIP) analyses demonstrate that P-TEFb is recruited to the actual papillomavirus episomes. We also show that E2's interaction with cellular chromatin through Brd4 correlates with its papillomavirus transcription activation function since JQ1(+), a bromodomain inhibitor that efficiently dissociates E2-Brd4 complexes from chromatin, potently reduces papillomavirus transcription. Our study identifies a specific function of Brd4 in papillomavirus gene transcription and highlights the potential use of bromodomain inhibitors as a method to disrupt the human papillomavirus (HPV) life cycle. PMID:25140737
Functional Selection of Hepatitis C Virus Envelope E2-Binding Peptide Ligands by Using Ribosome Display ?
Chen, Fang; Zhao, Yinglan; Liu, Min; Li, Dongqing; Wu, Hongyan; Chen, Haidan; Zhu, Yongzhe; Luo, Fengling; Zhong, Jin; Zhou, Yidan; Qi, Zhongtian; Zhang, Xiao-Lian
Small peptides that inhibit the hepatitis C virus (HCV) at the stage of viral entry have the potential to serve as attractive antiviral drugs. Ribosome display is a cell-free system for in vitro selection of peptides from large random peptide libraries. Thus, we utilized a ribosome display library technique for affinity selection of HCV envelope protein E2-binding peptide ligands. Through 13 rounds of selection, the ribosome display system generated high-affinity 12-mer peptides, and the selected peptide PE2D (MARHRNWPLVMV) demonstrated the highest specificity and affinity to the HCV E2 protein. Furthermore, amino acids 489 to 508 (YPPRPCGIVPAKSVCGPVYC) of E2 were identified as crucial for binding to PE2D. The selected peptides, especially PE2D, not only dramatically blocked E2 protein binding to hepatocytes but also dramatically inhibited HCV cell culture (HCVcc) entry into hepatocytes. HCVcc and HCV particles from HCV patient serum samples could also be specifically captured using PE2D. Our study demonstrates that the newly selected peptide ligand PE2D holds great promise for developing a new molecular probe, a therapeutic drug specifically for HCV, or an early-diagnostic reagent for HCV surface envelope antigen E2. PMID:20479194
Apolipoprotein E ?4 is superior to apolipoprotein E ?2 in predicting cognitive scores over 30 months
Regal, Paul; Nair, Balakrishnan; Hetherington, Eileen
Background The purpose of this study was to compare apolipoprotein E ?4 (Apo E ?4) and apolipoprotein E ?2 (Apo E ?2) as predictors of cognitive and functional trajectories over 30 months. Methods This prospective cohort study included 287 community-dwelling memory clinic patients with dementia, mild cognitive impairment, or no cognitive impairment. The Addenbrooke Cognitive Examination, Mini-Mental State Examination, Montreal Cognitive Assessment, Delirium Index, and Nottingham Instrumental Activities of Daily Living tests were administered to each subject. Results One hundred and nine subjects (40%) carried Apo E ?4 and 48 (16.7%) carried Apo E ?2. One hundred and nine ?4-positive subjects differed significantly from 178 ?4-negative subjects in 19/52 comparisons (36.5%), whereas 46 Apo E ?2-positive subjects had 0/52 significant differences from 239 ?2-negative subjects (P < 0.0001). The variables most affected by ?4 were the Delirium Index and Mini-Mental State Examination. Instrumental Activities of Daily Living score and residence were unrelated to Apo E ?4 or ?2. Conclusion Apo E ?4 positivity predicted four cognitive scores measured every 6 months over 30 months. Apo E ?2 scores predicted none of 52 comparisons. PMID:24204131
A Complex with Chromatin Modifiers That Occupies E2F- and Myc-Responsive Genes in G0 Cells
Hidesato Ogawa; Kei-ichiro Ishiguro; Stefan Gaubatz; David M. Livingston; Yoshihiro Nakatani
E2F-6 contributes to gene silencing in a manner independent of retinoblastoma protein family members. To better elucidate the molecular mechanism of repression by E2F-6, we have purified the factor from cultured cells. E2F-6 is found in a multimeric protein complex that contains Mga and Max, and thus the complex can bind not only to the E2F-binding site but also to
Transcription Factors ETF, E2F, and SP-1 Are Involved in Cytokine-Independent Proliferation of Murine
Timmer, Jens
Transcription Factors ETF, E2F, and SP-1 Are Involved in Cytokine-Independent Proliferation-regulated. The latter genes showed an overrepresen- tation of transcription factor binding sites (TFBS) for ETF (TEA hepatectomy con- tained overrepresented TFBS for ETF, E2F1, and SP-1 and displayed increased expression of E2F
B(E2) Evaluation for 0+ to 2+ Transitions in Even-Even Nuclei
B. Pritychenko; M. Birch; M. Horoi; B. Singh
A collaborative study by Brookhaven-McMaster-Central Michigan is underway to evaluate B(E2)$\\uparrow$ for 0$^{+}_{1}$ $\\rightarrow$ 2$^{+}_{1}$ transitions. This work is a continuation of a previous USNDP evaluation and has been motivated by a large number of recent measurements and nuclear theory developments. It includes an extended compilation, data evaluation procedures and shell model calculations. The subset of B(E2)$\\uparrow$ recommended values for nuclei of relevance to the double-beta decay problem is presented, and evaluation policies of experimental data and systematics are discussed. Future plans for completion of the B(E2;0$^{+}_{1}$ $\\rightarrow$ 2$^{+}_{1}$) evaluation project are also described.
TGF{beta}-mediated formation of pRb-E2F complexes in human myeloid leukemia cells
Hu Xiaotang [School of Natural and Health Science, Barry University, 11300 Northeast Second Avenue, Miami Shores, FL 33161 (United States)], E-mail: firstname.lastname@example.com
TGF{beta} is well known for its inhibitory effect on cell cycle G1 checkpoint kinases. However, its role in the control of pRb-E2F complexes is not well established. TGF{beta} inhibits phosphorylation of pRb at several serine and threonine residues and regulates the association of E2F transcription factors with pRb family proteins. Recent studies found that predominantly E2F-4, p130, and histone deacetylase (HDAC) are found to bind to corresponding E2F-responsive promoters in G0/G1 phase. As cells progress through mid-G1, p130-E2F4 complex are replaced by p107-E2F4 followed by activators E2F1, 2, and 3. pRb was not detectable in the promoters containing the E2F-responsive site in cycling cells but was associated with E2F4-p130 complexes or E2F4-p107 complexes during G0/G1 phase. In human myeloid leukemia cell line, MV4-11, TGF{beta} upregulated pRb-E2F-4 and p130-E2F-4, and downregulated p107-E2F-4 complexes. However, pRB-E2F1 and pRb-E2F3 complexes were found in proliferating cells but not in TGF{beta} arrested G1 cells. In addition, electrophoretic gel mobility shift assay (EMSA) could not detect pRb-E2F DNA-binding activities either in S or G1 phase but exhibited the existence of p107-E2F4 in proliferating cells and p130-E2F4 complexes in TGF{beta}-arrested G1 cells, respectively. Our data suggest that p107 and p130, but not pRb, and the repressor E2F, but not activator E2Fs, play a critical role in regulating E2F-responsive gene expression in TGF{beta}-mediated cell cycle control in human myeloid leukemia cells.
Control of Drosophila endocycles by E2F and CRL4Cdt2
Zielke, Norman; Kim, Kerry J.; Tran, Vuong; Shibutani, Shusaku T.; Bravo, Maria-Jose; Nagarajan, Sabarish; van Straaten, Monique; Woods, Brigitte; von Dassow, George; Rottig, Carmen; Lehner, Christian F.; Grewal, Savraj; Duronio, Robert J.
Endocycles are variant cell cycles comprised of DNA Synthesis (S)- and Gap (G)- phases but lacking mitosis1,2. Such cycles facilitate post-mitotic growth in many invertebrate and plant cells, and are so ubiquitous that they may account for up to half the world's biomass3,4. DNA replication in endocycling Drosophila cells is triggered by Cyclin E/Cyclin Dependent Kinase 2 (CycE/Cdk2), but this kinase must be inactivated during each G-phase to allow the assembly of pre-Replication Complexes (preRCs) for the next S-phase5,6. How CycE/Cdk2 is periodically silenced to allow re-replication has not been established. Here, using genetic tests in parallel with computational modeling, we show that Drosophila's endocycles are driven by a molecular oscillator in which the E2F1 transcription factor promotes CycE expression and S-phase initiation, S-phase then activates the CRL4Cdt2 ubiquitin ligase, and this in turn mediates the destruction of E2F17. We propose that it is the transient loss of E2F1 during S-phases that creates the window of low Cdk activity required for preRC formation. In support of this model over-expressed E2F1 accelerated endocycling, whereas a stabilized variant of E2F1 blocked endocycling by de-regulating target genes including CycE, as well as Cdk1 and mitotic Cyclins. Moreover, we find that altering cell growth by changing nutrition or TOR signaling impacts E2F1 translation, thereby making endocycle progression growth-dependent. Many of the regulatory interactions essential to this novel cell cycle oscillator are conserved in animals and plants1,2,8, suggesting that elements of this mechanism act in most growth-dependent cell cycles. PMID:22037307
Theory of Deep Minima in (e, 2e) Measurements of Triply Differential Cross Sections
Macek, Joseph H [ORNL; Sternberg, James [ORNL; Ovchinnikov, Serguei Yurevich [ORNL; Briggs, J. S. [University of Freiburg, Germany
Deep minima in He(e,2e)He{sup +} triply differential cross sections are traced to vortices in atomic wave functions. Such vortices have been predicted earlier, but the present calculations show that they have also been observed experimentally, although not recognized as vortices. Their observation in (e,2e) measurements shows that vortices play an important role in electron correlations related to the transfer of angular momentum between incident and ejected electrons. The vortices significantly extend the list of known features that summarize the general picture of electron correlations in impact ionization.
Second-order Born effect in coplanar doubly symmetric (e,2e) collisions for sodium
NASA Astrophysics Data System (ADS)
Wang, Yang; Jiao, Liguang; Zhou, Yajun
The second-order distorted wave Born approximation (DWBA) method is employed to investigate the triple differential cross sections (TDCS) of coplanar doubly symmetric (e,2e) collisions for alkali target sodium at excess energies of 6-60 eV. Comparing with the first-order DWBA calculations, the inclusion of second-order Born term in the scattering amplitude improves the degree of agreement with experiments, especially for backward scattering region of TDCS. This indicates the present second-order Born term is capable to give a reasonable correction to DWBA model in studying coplanar symmetric (e,2e) problems in low and intermediate energy range.
Choriogenin mRNA as a sensitive molecular biomarker for estrogenic chemicals in developing brackish medaka (Oryzias melastigma).
Chen, Xueping; Li, Vincent Wai Tsun; Yu, Richard Man Kit; Cheng, Shuk Han
Teleost choriogenins, precursors of the inner layer subunits of the egg envelope, are regarded as sensitive biomarkers for estrogenic pollutants. In this study, two full-length cDNAs, omChgH and omChgL, which encode the choriogenin H and L forms, respectively, were isolated from a brackish medaka, Oryzias melastigma. 17beta-Estradiol (E2; 10 microg/L)-dependent expression of omChgH and omChgL was observed starting at embryonic stage 34 and restricted exclusively to the liver. In hatchlings, E2 induction of omChgH was stronger than that of omChgL. Static exposure of adult fish to E2 (0, 1, 10, 100, and 500 ng/L), 17alpha-ethinylestradiol (EE2; 0, 1, 10, 100 and 500 ng/L), 4-nonylphenol (NP; 0, 1, 10, 100, and 200 microg/L), and bisphenol A (BPA; 0, 1, 10, 100, and 200 microg/L) in artificial seawater for 7 days resulted in dose-dependent induction of both genes in the liver. In the male livers, the sensitivity of omChgH to these estrogenic compounds was higher than that of omChgL; the lowest-observed-effect concentrations (LOECs) of E2, EE2, NP, and BPA on omChgH were 10 ng/L, 10 ng/L, 100 microg/L and 100 microg/L, respectively, and on omChgL were 100 ng/L, 100 ng/L, 100 microg/L, and 200 microg/L, respectively. All these suggest that omChgH can be used as a highly sensitive biomarker for monitoring estrogenic chemicals in the marine environment. PMID:18048097
A bench-scale assessment of ozone pre-treatments for landfill leachates.
Qiao, Yu; Do, Anh; Yeh, Daniel; Watt, Michael J
Leachate from stabilized landfill can pose unique challenges to conventional biological wastewater treatment. Ozone-based advanced oxidation processes have garnered recent consideration as an option to reduce the organic strength and recalcitrance of aged landfill leachate. With a bench-scale investigation, the reported work examines the potential for leachate conditioning for further biological treatment by treatment with low-mg/L doses of ozone (0-7.5 mg/L 03). While not sufficient for significant organics mineralization, the tested ozone doses could potentially produce both selective and non-selective oxidation of recalcitrant leachate organic compounds leaving bio-available products in the pre-treated leachate. Leachate conditioning by 03 or 03/H202 was assessed via monitoring of three anthropogenic organic leachate contaminants(tris-(2-chloroethyl) phosphate, tris-(butoxyethyl)-phosphate and 17beta-estradiol (E2)) with ozonation, and ozonation followed by anaerobic incubation. In addition, chemical oxygen demand (COD) and BOD5 analysis of the ozonated leachate, and methane and total gas formation during the anaerobic incubation were used to assess the degree of leachate conditioning. When treated with O3 alone, 58% removal of E2 was observed with an ozone dose of 4.5-5.4mg/L. Direct oxidation of the three leachate contaminants was limited with O3/H202 pre-treatment. However, this pre-treatment was observed to have significantly improved degradation of E2 during anaerobic incubation of ozonated leachates (removal rate of E2 was 53.7% with 15 days of incubation), indicating the potential for ozone synthesized co-metabolism. However, overall anaerobic microbial activity was not significantly impacted by the applied ozone pre-treatments, as measured by methane formation, total gas formation, and COD removal during incubation. PMID:24600851
Effects of sulfathiazole, oxytetracycline and chlortetracycline on steroidogenesis in the human adrenocarcinoma (H295R) cell line and freshwater fish Oryzias latipes.
Ji, Kyunghee; Choi, Kyungho; Lee, Sangwoo; Park, Saerom; Khim, Jong Seong; Jo, Eun-Hye; Choi, Kyunghee; Zhang, Xiaowei; Giesy, John P
Pharmaceuticals in the environment are of growing concern for their potential consequences on human and ecosystem health. Alterations in the endocrine system in humans or wildlife are of special interest because these alterations could eventually lead to changes in reproductive fitness. Using the H295R cell line, the potential endocrine disrupting effects of six pharmaceuticals including diclofenac, erythromycin, sulfamethazine, sulfathiazole, oxytetracycline, and chlortetracycline were investigated. After exposure to each target pharmaceutical for 48 h, production of 17beta-estradiol (E2) and testosterone (T), aromatase (CYP19) enzyme activity, or expression of steroidogenic genes were measured. Concentrations of E2 in blood plasma were determined in male Japanese medaka fish after 14 d exposure to sulfathiazole, oxytetracycline, or chlortetracycline. Among the pharmaceuticals studied, sulfathiazole, oxytetracycline and chlortetracycline all significantly affected E2 production by H295R cells. This mechanism of the effect was enhanced aromatase activity and up-regulation of mRNAs for CYP17, CYP19, and 3betaHSD, all of which are important components of steroidogenic pathways. Sulfathiazole was the most potent compound affecting steroidogenesis in H295R cells, followed by chlortetracycline and oxytetracycline. Sulfathiazole significantly increased aromatase activity at 0.2 mg/l. In medaka fish, concentrations of E2 in plasma increased significantly during 14-d exposure to 50 or 500 mg/l sulfathiazole, or 40 mg/l chlortetracycline. Based on the results of this study, certain pharmaceuticals could affect steroidogenic pathway and alter sex hormone balance. Concentrations of the pharmaceuticals studied that have been reported to occur in rivers of Korea are much less than the thresholds for effects on the endpoints studied here. Thus, it is unlikely that these pharmaceuticals are causing adverse effects on fish in those rivers. PMID:20630653
Endocrine control of sexual behavior in sneaker males of the peacock blenny Salaria pavo: effects of castration, aromatase inhibition, testosterone and estradiol.
Gonçalves, David; Alpedrinha, Joăo; Teles, Magda; Oliveira, Rui F
The effects of castration and sex steroid manipulations on the expression of sexual behavior were investigated in a small fish, the peacock blenny, Salaria pavo. In this species, large males defend nests and attract females while small "sneaker" males reproduce by imitating the female morphology and courtship behavior in order to approach nests during spawning events and parasitically fertilize eggs. Sneakers switch into nest holders in their second breeding season, thus displaying both male and female-like sexual behavior during their lifetime. We tested the effects of castration and of an aromatase inhibitor (Fadrozole, F), testosterone (T) or 17beta-estradiol (E(2)) implants on the expression of male and female-like behavior in sneakers. Sneakers were either sham-operated, castrated or castrated and implanted with vehicle, F, T+F or E(2)+F. Seven days after the treatment, sneakers were placed in a tank with a nesting male, two ripe females and an available nest. Castrated fish had lower levels of circulating T and increased the time spent displaying female typical nuptial coloration. T implants had the opposite effect, inhibiting the expression of female-like behavior and coloration. E(2) implants had no significant effect on the display of sexual behavior but the frequency of aggressive displays decreased. The results agree with previous findings in sneakers of S. pavo that demonstrated an inhibition of female-like behavior by 11-ketotestosterone (11-KT). The reported increase in T and 11-KT production when sneakers change into nest holders may thus contribute to behaviorally defeminize sneakers. Contrarily, both T and E(2) failed to promote male-like behavior, suggesting that behavioral masculization during tactic switching depends on other neuroendocrine mechanisms or that the time length of the experiment was insufficient to induce male-like behavioral changes in sneakers. PMID:17368457
Inhibitory effects of a dietary phytochemical 3,3'-diindolylmethane on the phenobarbital-induced hepatic CYP mRNA expression and CYP-catalyzed reactions in female rats.
Parkin, Daniel R; Lu, Yongjian; Bliss, Robin L; Malejka-Giganti, Danuta
3,3'-diindolylmethane (DIM), derived from indole-3-carbinol (I3C), is used as a dietary supplement for its putative anticancer effects that include suppression of mammary tumor growth in female rats. The mechanism of action DIM may involve its interaction(s) with hepatic cytochromes P450 (CYPs) catalyzing oxidations of 17beta-estradiol (E2). Our study showed that DIM added to hepatic microsomes of female Sprague-Dawley rats was primarily a competitive inhibitor of beta-naphthoflavone (beta-NF)- or I3C-induced CYP1A1 probe activity, and a potent mixed or uncompetitive inhibitor of phenobarbital (PB)-induced CYP2B1 or CYP2B2 probe activity, respectively. Microsomal metabolites of DIM were tentatively identified as two mono-hydroxy isomers of DIM, each formed preferentially by CYP1A1- or CYP2B1/2-catalyzed reaction. Evaluation of the effects of co-treatment of rats with PB and DIM by a full factorial ANOVA showed that DIM decreased the PB-induced CYP2B1 and CYP2B2 mRNA expression levels, and the rates of 2- and 4-hydroxylation of E2, and total E2 metabolite formation. The results suggest that interactions of DIM, and/or its mono-hydroxy metabolites, with CYP2B1 and CYP2B2 found to occur in hepatic microsomes upon addition of DIM or co-treatment of rats with DIM affect the rates of relevant oxidations of E2, and potentially protect against estrogen-dependent tumorigenesis. PMID:18486294
Effects of sex, age, and season on plasma steroids in free-ranging Texas horned lizards (Phrynosoma cornutum).
Wack, Corina L; Fox, Stanley F; Hellgren, Eric C; Lovern, Matthew B
The Texas horned lizard (Phrynosoma cornutum) is protected in several states due to its apparently declining numbers; information on its physiology is therefore of interest from both comparative endocrine and applied perspectives. We collected blood samples from free-ranging P. cornutum in Oklahoma from April to September 2005, spanning their complete active period. We determined plasma concentrations of the steroids, progesterone (P), testosterone (T), and corticosterone (CORT) by radioimmunoassay following chromatographic separation and 17beta-estradiol (E2) by direct radioimmunoassay. T concentrations in breeding males were significantly higher than in non-breeding males. P showed no significant seasonal variation within either sex. CORT was significantly higher during the egg-laying season compared to breeding and non-breeding seasons for adult females and it was marginally higher in breeding than in non-breeding males (P=0.055). CORT concentrations also significantly increased with handling in non-breeding males and egg-laying females. Perhaps most surprisingly, there were no significant sex differences in plasma concentrations of P and E2. Furthermore, with respect to seasonal differences, plasma E2 concentrations were significantly higher in breeding females than in egg-laying or non-breeding females, and they were significantly higher in breeding than in non-breeding males. During the non-breeding season, yearling males exhibited higher E2 concentrations than adult males; no other differences between the steroid concentrations of yearlings and adults were detected. In comparison to other vertebrates, the seasonal steroid profile of P. cornutum exhibited both expected and unexpected patterns, and our results illustrate the value of collecting such baseline data as a springboard for appropriate questions for future research. PMID:18048031
Direct evidence for the localization of the steroid-binding site of the plasma sex steroid-binding protein (SBP or SHBG) at the interface between the subunits.
Sui, L. M.; Hughes, W.; Hoppe, A. J.; Pétra, P. H.
Complete dissociation of dimeric plasma sex steroid-binding protein (SBP or SHBG) was obtained in 6 M urea at 10 degrees C. Removal of urea resulted in the refolding of monomers, followed by reformation of dimeric SBP, which migrates with the same mobility as the native protein. Dimerization does not require Ca+2 or steroid. Renatured monomers yield dimers with dissociation constants for 5 alpha-dihydrotesterone (DHT) and 17 beta-estradiol (E2) indistinguishable from those of native human SBP. This phenomenon was also demonstrated by mixing human and rabbit SBPs that, upon renaturation, form a hybrid dimer composed of one human subunit and one rabbit subunit. The hybrid binds both DHT and E2 in contrast to rSBP, which only binds the androgen. Therefore, we conclude that (1) docking of the two subunits creates an asymmetric steroid-binding site located at the interface between the subunits, and (2) only one face of the dimer defines the specificity for binding E2 by encompassing portion of a structural motif that recognizes the flat ring A of E2. The remaining portion, which recognizes the saturated ring A of DHT, is shared by both faces of the dimer. Because native monomers do not exist alone, the often-asked question of whether the SBP monomer binds steroid can be considered meaningless; steroid-binding activity is expressed only in the dimeric state. Finally, formation of the hybrid indicates that SBP dimerization represents a conserved event during the molecular evolution of SBP, suggesting that the structural elements responsible for dimerization will be homologous in SBPs from other species. PMID:8976560
Differential Functions for the Transcription Factor E2A in Positive and Negative Gene Regulation in Pre-B Lymphocytes*
Greenbaum, Stephen; Lazorchak, Adam S.; Zhuang, Yuan
The transcription factors encoded by the E2A gene have been shown to play essential roles in the initiation and progression of lymphocyte development. However, there is still a lack of comprehensive understanding of E2A downstream genes in B-cell development. We previously developed a gene tagging-based chromatin immunoprecipitation (ChIP) system to directly evaluate E2A target genes in B-cell development. Here, we have improved this ChIP strategy and used it in conjunction with microarray analysis on E2A-deficient pre-B-cell lines to determine E2A target genes in lymphocyte development. Both microarray data and ChIP studies confirmed that E2A directly controls IgH gene expression. The microarray assay also revealed genes that were significantly up-regulated after E2A disruption. ChIP analysis showed that E2A was most likely to be directly involved in repression of some of these target genes such as Nfil3 and FGFR2. An inducible E2A reconstitution system further demonstrated that E2A-mediated repression of Nfil3 and FGFR2 was reversible. Collectively, these findings indicate that E2A is a positive regulator for one set of genes and a negative regulator for another set of genes in developing B lymphocytes. PMID:15310760
Techno - economic of collaborative based secondary spectrum usage - E2R research project outcomes overview
David Grandblaise; Clemens Kloeck; Klaus Moessner; Virgilio Rodriguez; Eiman Mohyeldin; M. K. Pereirasamy; Jijun Luo; I. Martoyo
The under-use of spectrum offers new perspective for a secondary usage of the spectrum. However, this can be achieved at the expense of a tight spectrum sharing control and management between the different involved parties (operators and users). This paper presents the latest research achievements of a major European research initiative (E2 R project) in the field of flexible spectrum
v-Abl activates c-myc transcription through the E2F site
Wong, Kwok-Kin; Merrell, K.T.; Zou, Xiaoming; Marcu, K.B. [Columbia Univ., New York, NY (United States)] [and others
This research explores the mechanism by which vAbl activates c-myc transcription by developing a cotransfection assay. v-Abl tyrosine kinase dependent changes in proteins binding c-myc E2F site were also demonstrated, which provides an important link between v-Abl, transcription, cell cycle regulation, and control of ceo growth. 67 refs., 8 figs.
J U N E 2 0 0 0 Research Report 2000/5
Flinn, Jason
J U N E 2 0 0 0 WRL Research Report 2000/5 Quantifying the Energy Consumption of a Pocket Computer Report Distribution Compaq Western Research Laboratory 250 University Avenue Palo Alto, CA 94301 U Research Laboratory 250 University Avenue Palo Alto, California 94301 USA #12;The Western Research
Dynamic Tensile Testing of Kevlar 49 Fabrics ; Barzin Mobasher, Ph.D., P.E.2
Mobasher, Barzin
Dynamic Tensile Testing of Kevlar 49 Fabrics Deju Zhu1 ; Barzin Mobasher, Ph.D., P.E.2 of strain. Kevlar-49 fabrics were tested in tension within a strain-rate range of 25 to 170 sŔ1 using a high nature of Kevlar-49 fabric results in large displacements and shape changes during tests. Noncontacting
Isoscalar E0, E1, and E2 strength in Ca-40
Youngblood, David H.; Lui, YW; Clark, HL.
The giant resonance region from 10 particles at small angles including 0 degrees. Strength corresponding to 97 +/- 11%, 108 +/- 12%, and 62 + 10-20 % of the isoscalar E0, E2, and E1 sum rules, respectively, was identified with centroids of 19...
Environment to Environment (E2E) Communication Systems for Collaborative Work
Reif, Rafael
Environment to Environment (E2E) Communication Systems for Collaborative Work Ish Rishabh irishabh with intelligent sensing of environments, to provide effective bi-directional communication which is free from, connecting environments, sentient communication. ACM Classification Keywords H5.1. Multimedia information
Stages of Change – Continuous Measure (URICA-E2): psychometrics of a Norwegian version
Lerdal, Anners; Moe, Britt; Digre, Elin; Harding, Thomas; Kristensen, Frode; Grov, Ellen K; Bakken, Linda N; Eklund, Marthe L; Ruud, Ireen; Rossi, Joseph S
Title Stages of Change – Continuous Measure (URICA-E2): psychometrics of a Norwegian version. Aim This paper is a report of research to translate the English version of the Stages of Change continuous measure questionnaire (URICA-E2) into Norwegian and to test the validity of the questionnaire and its usefulness in predicting behavioural change. Background While the psychometric properties of the Stages of Change categorical measure have been tested extensively, evaluation of the psychometric properties of the continuous questionnaire has not been described elsewhere in the literature. Method Cross-sectional data were collected with a convenience sample of 198 undergraduate nursing students in 2005 and 2006. The English version of URICA-E2 was translated into Norwegian according to standardized procedures. Findings Principal components analysis clearly confirmed five of the dimensions of readiness to change (Precontemplation Non-Believers, Precontemplation Believers, Contemplation, Preparation and Maintenance), while the sixth dimension, Action, showed the lowest Eigenvalue (0·93). Findings from the cluster analysis indicate distinct profiles among the respondents in terms of readiness to change their exercise behaviour. Conclusion The URICA-E2 was for the most part replicated from Reed's original work. The result of the cluster analysis of the items associated with the factor 'Action' suggests that these do not adequately measure the factor. PMID:19032513
DOE Hydrogen Program FY 2004 Progress Report II.E.2 Photoelectrochemical Hydrogen Production
DOE Hydrogen Program FY 2004 Progress Report II.E.2 Photoelectrochemical Hydrogen Production Eric L) 956-5337; Fax: (808) 956-2336; E-mail: firstname.lastname@example.com DOE Technology Development Manager: Roxanne Danz Phone: (202) 586-7260; Fax: (202) 586-9811; E-mail: email@example.com Objectives · To assist
Boyer, Edmond
THE EFFECT OF PROSTAGLANDIN E2 ON THYROIDAL SECRETION OF HORMONAL IODINE IN THE PIG G. CABELLO A. D a significant dose-dependent reduction in hormonal iodine secretion rate was observed. These results confirm secretion of hormonal iodine in the pig.. METHODS AND RESULTS The thyroid gland in 4 pigs was isolated
E.2. Electronic Appendix -Food Web Elements of the Fraser River Upper River (above rkm 210)
1 E.2. Electronic Appendix - Food Web Elements of the Fraser River Basin Upper River (above rkm 210) Food webs: Microbenthic algae (periphyton), detritus from riparian vegetation and littoral insects). Stressors: Water quality and habitat conditions have changed food webs in specific locations in the upper
Dynamical (e,2e) investigations of tetrahydrofuran and tetrahydrofurfuryl alcohol as DNA analogues
Wang, Yayu
Dynamical (e,2e) investigations of tetrahydrofuran and tetrahydrofurfuryl alcohol as DNA analogues previ- ous measurements on THF and tetrahydrofurfuryl alcohol to further understand the role-molecules is to be accurately simulated, we need to identify and understand the role of isolated chemical structures within them
Scattering operators for E1-E2 x-ray resonant diffraction
NASA Astrophysics Data System (ADS)
Marri, Ivan; Carra, Paolo
Resonant x-ray diffraction in noncentrosymmetric crystals is studied by considering E1-E2 processes in the fast-collision approximation. The scattering amplitude is expressed in terms of polar and magnetoelectric operators of the valence states, which are involved in the resonance. Near-edge Bragg peaks from ferroelectric, antiferroelectric, and magnetoelectric structures are predicted.
E2E blocking probability of IPTV and P2PTV? , Fernando Kuipers1
Van Mieghem, Piet
E2E blocking probability of IPTV and P2PTV? Yue Lu1 , Fernando Kuipers1 , Milena Janic2 and Piet for IPTV or P2PTV based on the Quality of Experience (QoE). In this paper, we investigate one important Qo different ways: either utilizing a mechanism on the IP layer (IPTV) or on the application layer (P2PTV
Crystal structure of glycoprotein E2 from bovine viral diarrhea virus.
Li, Yue; Wang, Jimin; Kanai, Ryuta; Modis, Yorgo
Pestiviruses, including bovine viral diarrhea virus, are important animal pathogens and are closely related to hepatitis C virus, which remains a major global health threat. They have an outer lipid envelope bearing two glycoproteins, E1 and E2, required for cell entry. They deliver their genome into the host cell cytoplasm by fusion of their envelope with a cellular membrane. The crystal structure of bovine viral diarrhea virus E2 reveals a unique protein architecture consisting of two Ig-like domains followed by an elongated ?-stranded domain with a new fold. E2 forms end-to-end homodimers with a conserved C-terminal motif rich in aromatic residues at the contact. A disulfide bond across the interface explains the acid resistance of pestiviruses and their requirement for a redox activation step to initiate fusion. From the structure of E2, we propose alternative possible membrane fusion mechanisms. We expect the pestivirus fusion apparatus to be conserved in hepatitis C virus. PMID:23569276
Equilibrium dissociation and unfolding of human papillomavirus E2 transactivation domain.
Singh, Nitu; Kanthaje, Shruthi; Bose, Kakoli
Papillomavirus E2 protein that performs essential functions such as viral oncogene expression and replication represents specific target for therapeutic intervention. DNA-binding activity is associated with its C-terminal DNA-binding domain (DBD), while the N-terminal transactivation domain (TAD) is responsible for replication and transactivation functions. Although both demonstrate large dependence on dimerization for mediating their functions, KD for N-terminal dimerization is significantly high suggesting more dynamic role of this domain. However, unlike DBD, very little information is available on TAD dimerization, its folding and stability. Therefore, with an aim at delineating the regulatory switch of its dimerization, we have characterized high-risk HPV18 E2 TAD. Our studies demonstrate that E2 TAD is a weak but thermodynamically stable dimer (KD ? 1.8 ?M, [Formula: see text] = 18.8 kcal mol(-1)) with ?2-?3 helices forming the interface. It follows a three-state folding pathway, in which unfolding involves dissociation of a dimeric intermediate. Interestingly, 90% of the conformational free energy is associated with dimer dissociation (16.9 of 18.8 kcal mol(-1)) suggesting dimerization significantly contributes to its overall thermodynamic stability. These revelations might be important toward designing inhibitors for targeting dimerization or folding intermediates and hence multiple functions that E2 performs. PMID:26091566
Orbital M1 versus E2 strength in deformed nuclei: A new energy weighted sum rule
E. Moya de Guerra; L. Zamick
Within the unified model of Bohr and Mottelson we derive the following linear energy weighted sum rule for low energy orbital 1$^+$ excitations in even-even deformed nuclei $$S_{\\rm LE}^{\\rm lew} (M_1^{\\rm orb}) \\cong (6/5) \\epsilon (B(E2; 0^+_1 \\rightarrow 2_1^+ K=0)/Z e^2^2) \\mu^2_N$$ with B(E2) the E2 strength for the transition from the ground state to the first excited state in the ground state rotational band, $$ the charge r.m.s. radius squared and $\\epsilon$ the binding energy per nucleon in the nuclear ground state. It is shown that this energy weighted sum rule is in good agreement with available experimental data. The sum rule is derived using a simple ansatz for the intrinsic ground state wave function that predicts also high energy 1$^+$ strength at 2$\\hbar \\omega$ carrying 50\\% of the total $m_1$ moment of the orbital M1 operator.
Objective: To evaluate the use of vaginal misoprostol compared with vaginal prostaglandin E2 (PGE2) for labour induction at term. Design: Experimental. Setting: Gynae Unit III, Department of Obstetrics and Gynaecology SIMS \\/ Services Hospital Lahore. Methods: Patients were randomized to two groups with 100 patients in each group. One group received 50?g of misoprostol vaginally every four hours up till
Phage display identifies an Eastern equine encephalitis virus glycoprotein E2-specific B cell epitope.
Zhao, J; Sun, E C; Liu, N H; Yang, T; Xu, Q Y; Qin, Y L; Yang, Y H; Wu, D L
The present study identified a linear B-cell epitope in the Eastern equine encephalitis virus (EEEV) E2 glycoprotein by screening a phage-displayed random 12-mer peptide library using an EEEV E2 specific monoclonal antibody (mAb) 7C11 and defined L/F-E/R-Y-T-W-G/R-N-H/W-P as the consensus binding motif. A sequence ((321)EGLEYTWGNHPP(332)) encompassing this consensus motif was found in the EEEV E2 glycoprotein and synthesized for further epitope confirmation. Meanwhile, the corresponding epitope peptides in E2 protein of associated alphaviruses were synthesized for specificity identification. Results showed the mAb 7C11 and murine antisera all reacted strongly against the synthesized polypeptide of EEEV antigen complex, but no reaction with Western equine encephalitis virus (WEEV) and Venezuelan equine encephalitis virus (VEEV) was detected. The knowledge and reagents generated in this study may have potential applications in differential diagnosis and the development of epitope-based marker vaccines against EEEV. PMID:22824180
The E2F Transcription Factors Regulate Tumor Development and Metastasis in a Mouse Model of Metastatic Breast Cancer
Hollern, Daniel P.; Honeysett, Jordan; Cardiff, Robert D.
While the E2F transcription factors (E2Fs) have a clearly defined role in cell cycle control, recent work has uncovered new functions. Using genomic signature methods, we predicted a role for the activator E2F transcription factors in the mouse mammary tumor virus (MMTV)-polyomavirus middle T oncoprotein (PyMT) mouse model of metastatic breast cancer. To genetically test the hypothesis that the E2Fs function to regulate tumor development and metastasis, we interbred MMTV-PyMT mice with E2F1, E2F2, or E2F3 knockout mice. With the ablation of individual E2Fs, we noted alterations of tumor latency, histology, and vasculature. Interestingly, we noted striking reductions in metastatic capacity and in the number of circulating tumor cells in both the E2F1 and E2F2 knockout backgrounds. Investigating E2F target genes that mediate metastasis, we found that E2F loss led to decreased levels of vascular endothelial growth factor (Vegfa), Bmp4, Cyr61, Nupr1, Plod 2, P4ha1, Adamts1, Lgals3, and Angpt2. These gene expression changes indicate that the E2Fs control the expression of genes critical to angiogenesis, the remodeling of the extracellular matrix, tumor cell survival, and tumor cell interactions with vascular endothelial cells that facilitate metastasis to the lungs. Taken together, these results reveal that the E2F transcription factors play key roles in mediating tumor development and metastasis in addition to their well-characterized roles in cell cycle control. PMID:24934442
The E2F transcription factors regulate tumor development and metastasis in a mouse model of metastatic breast cancer.
Hollern, Daniel P; Honeysett, Jordan; Cardiff, Robert D; Andrechek, Eran R
While the E2F transcription factors (E2Fs) have a clearly defined role in cell cycle control, recent work has uncovered new functions. Using genomic signature methods, we predicted a role for the activator E2F transcription factors in the mouse mammary tumor virus (MMTV)-polyomavirus middle T oncoprotein (PyMT) mouse model of metastatic breast cancer. To genetically test the hypothesis that the E2Fs function to regulate tumor development and metastasis, we interbred MMTV-PyMT mice with E2F1, E2F2, or E2F3 knockout mice. With the ablation of individual E2Fs, we noted alterations of tumor latency, histology, and vasculature. Interestingly, we noted striking reductions in metastatic capacity and in the number of circulating tumor cells in both the E2F1 and E2F2 knockout backgrounds. Investigating E2F target genes that mediate metastasis, we found that E2F loss led to decreased levels of vascular endothelial growth factor (Vegfa), Bmp4, Cyr61, Nupr1, Plod 2, P4ha1, Adamts1, Lgals3, and Angpt2. These gene expression changes indicate that the E2Fs control the expression of genes critical to angiogenesis, the remodeling of the extracellular matrix, tumor cell survival, and tumor cell interactions with vascular endothelial cells that facilitate metastasis to the lungs. Taken together, these results reveal that the E2F transcription factors play key roles in mediating tumor development and metastasis in addition to their well-characterized roles in cell cycle control. PMID:24934442
E2F1 downregulation by arsenic trioxide in lung adenocarcinoma.
Lam, Sze-Kwan; Li, Yuan-Yuan; Zheng, Chun-Yan; Leung, Leanne Lee; Ho, James Chung-Man
Lung cancer is one of the most common cancers worldwide. Arsenic trioxide (ATO) has been approved by the US Food and Drug Administration for the treatment of acute promyelocytic leukemia. Nonetheless preliminary data have suggested potential activity of ATO in solid tumors including lung cancer. This study aimed to examine the underlying mechanisms of ATO in the treatment of lung adenocarcinoma. Using a panel of 7 lung adenocarcinoma cell lines, the effects of ATO treatment on cell viability, expression of E2F1 and its downstream targets, phosphatidylserine externalization, mitochondrial membrane depolarization and alteration of apoptotic/anti-apoptotic factors were studied. Tumor growth inhibition in vivo was investigated using a nude mouse xenograft model. ATO decreased cell viability with clinically achievable concentrations (8 µM) in all cell lines investigated. This was accompanied by reduced expression of E2F1, cyclin A2, skp2, c-myc, thymidine kinase and ribonucleotide reductase M1, while p-c-Jun was upregulated. Cell viability was significantly decreased with E2F1 knockdown. Treatment with ATO resulted in phosphatidylserine externalization in H23 cells and mitochondrial membrane depolarization in all cell lines, associated with truncation of Bid, downregulation of Bcl-2, upregulation of Bax and Bak, caspase-9 and -3 activation and PARP cleavage. Using the H358 xenograft model, the tumor growth was suppressed in the ATO treatment group during 8 days of treatment, associated with downregulation of E2F1 and upregulation of truncated Bid and cleaved caspase-3. In conclusion, ATO has potent in vitro and in vivo activity in lung adenocarcinoma, partially mediated through E2F1 downregulation and apoptosis. PMID:25174355
BMI1 is a target gene of E2F-1 and is strongly expressed in primary neuroblastomas
Nowak, Katrin; Kerl, Kornelius; Fehr, Daniel; Kramps, Christoph; Gessner, Christine; Killmer, Katrin; Samans, Birgit; Berwanger, Bernd; Christiansen, Holger; Lutz, Werner
The oncogene BMI1 encodes a polycomb group transcription factor that is required for embryonic development and self-renewal of stem cells. Despite these important functions little is known about the regulation of BMI1 expression. A cDNA microarray based search for target genes of E2F-1 in neuroblastoma cells expressing a 4-OHT-regulated E2F-1-ER fusion protein identified many hitherto unknown E2F-1 regulated genes. A total of 10% of these genes, including BMI1, encode proteins that function primarily in the regulation of gene expression. The BMI1 promoter contains a putative E2F binding site that was required for the activation of a BMI1 promoter-dependent reporter construct by E2F-1. Chromatin immunoprecipitation revealed 4-OHT-dependent binding of E2F-1-ER and binding of endogenous E2F-1 to the BMI1 promoter in tumor cells. We have previously shown activation of the oncogene MYCN by E2F. Thus, in neuroblastomas deregulated E2F-1 can activate two oncogenes, MYCN and BMI1 that are known to co-operate in tumor formation. Consistent with a role of Bmi1 in neuroblastoma tumorigenesis we found strong Bmi1 expression in primary neuroblastomas. Our results reveal a novel link between E2F and polycomb transcription factors and suggest a role of Bmi1 in neuroblastomas. PMID:16582100
How Does (E)-2-(Acetamidomethylene)succinate Bind to Its Hydrolase? From the Binding Process to the Final Result
Zhang, Ji-Long; Zheng, Qing-Chuan; Li, Zheng-Qiang; Zhang, Hong-Xing
The binding of (E)-2-(acetamidomethylene)succinate (E-2AMS) to E-2AMS hydrolase is crucial for biological function of the enzyme and the last step reaction of vitamin B6 biological degradation. In the present study, several molecular simulation methods, including molecular docking, conventional molecular dynamics (MD), steered MD (SMD), and free energy calculation methods, were properly integrated to investigate the detailed binding process of E-2AMS to its hydrolase and to assign the optimal enzyme-substrate complex conformation. It was demonstrated that the substrate binding conformation with trans-form amide bond is energetically preferred conformation, in which E-2AMS's pose not only ensures hydrogen bond formation of its amide oxygen atom with the vicinal oxyanion hole but also provides probability of the hydrophobic interaction between its methyl moiety and the related enzyme's hydrophobic cavity. Several key residues, Arg146, Arg167, Tyr168, Arg179, and Tyr259, orientate the E-2AMS's pose and stabilize its conformation in the active site via the hydrogen bond interaction with E-2AMS. Sequentially, the binding process of E-2AMS to E-2AMS hydrolase was studied by SMD simulation, which shows the surprising conformational reversal of E-2AMS. Several important intermediate structures and some significant residues were identified in the simulation. It is stressed that Arg146 and Arg167 are two pivotal residues responsible for the conformational reversal of E-2AMS in the binding or unbinding. Our research has shed light onto the full binding process of the substrate to E-2AMS hydrolase, which could provide more penetrating insight into the interaction of E-2AMS with the enzyme and would help in the further exploration on the catalysis mechanism. PMID:23308285
Estrogen-mediated endothelial progenitor cell biology and kinetics for physiological postnatal vasculogenesis.
Masuda, Haruchika; Kalka, Christoph; Takahashi, Tomono; Yoshida, Miyoko; Wada, Mika; Kobori, Michiru; Itoh, Rie; Iwaguro, Hideki; Eguchi, Masamichi; Iwami, Yo; Tanaka, Rica; Nakagawa, Yoshihiro; Sugimoto, Atsuhiko; Ninomiya, Sayaka; Hayashi, Shinichiro; Kato, Shunichi; Asahara, Takayuki
Estrogen has been demonstrated to promote therapeutic reendothelialization after vascular injury by bone marrow (BM)-derived endothelial progenitor cell (EPC) mobilization and phenotypic modulation. We investigated the primary hypothesis that estrogen regulates physiological postnatal vasculogenesis by modulating bioactivity of BM-derived EPCs through the estrogen receptor (ER), in cyclic hormonally regulated endometrial neovascularization. Cultured human EPCs from peripheral blood mononuclear cells (PB-MNCs) disclosed consistent gene expression of ER alpha as well as downregulated gene expressions of ER beta. Under the physiological concentrations of estrogen (17beta-estradiol, E2), proliferation and migration were stimulated, whereas apoptosis was inhibited on day 7 cultured EPCs. These estrogen-induced activities were blocked by the receptor antagonist, ICI182,780 (ICI). In BM transplanted (BMT) mice with ovariectomy (OVX) from transgenic mice overexpressing beta-galactosidase (lacZ) regulated by an endothelial specific Tie-2 promoter (Tie-2/lacZ/BM), the uterus demonstrated a significant increase in BM-derived EPCs (lacZ expressing cells) incorporated into neovasculatures detected by CD31 immunohistochemistry after E2 administration. The BM-derived EPCs that were incorporated into the uterus dominantly expressed ER alpha, rather than ER beta in BMT mice from BM of transgenic mice overexpressing EGFP regulated by Tie-2 promoter with OVX (Tie-2/EGFP/BMT/OVX) by ERs fluorescence immunohistochemistry. An in vitro assay for colony forming activity as well as flow cytometry for CD133, CD34, KDR, and VE-cadherin, using human PB-MNCs at 5 stages of the female menstrual-cycle (early-proliferative, pre-ovulatory, post-ovulatory, mid-luteal, late-luteal), revealed cycle-specific regulation of EPC kinetics. These findings demonstrate that physiological postnatal vasculogenesis involves cyclic, E2-regulated bioactivity of BM-derived EPCs, predominantly through the ER alpha. PMID:17656679
Benzophenone-1 and nonylphenol stimulated MCF-7 breast cancer growth by regulating cell cycle and metastasis-related genes via an estrogen receptor ?-dependent pathway.
In, Sol-Ji; Kim, Seung-Hee; Go, Ryeo-Eun; Hwang, Kyung-A; Choi, Kyung-Chul
Endocrine-disrupting chemicals (EDC) are defined as environmental compounds that produce adverse health manifestations in mammals by disrupting the endocrine system. Benzophenone-1 (2,4-dihydroxybenzophenone, BP1) and nonylphenol (NP), which are discharged from numerous industrial products, are known EDC. The aim of this study was to examine the effects of BP1 and NP on proliferation and metastasis of MCF-7 human breast cancer cells expressing estrogen receptors (ER). Treatment with BP1 (10(-5)-10(-7)M) and NP (10(-6)-10(-7) M) promoted proliferation of MCF-7 cells similar to the positive control 17 -beta-estradiol (E2). When ICI 182,780, an ER antagonist, was co-incubated with E2, BP1, or NP, proliferation of MCF-7 cells returned to the level of a control. Addition of BP1 or NP markedly induced migration of MCF-7 cells similar to E2. To elucidate the underlying molecular mechanisms produced by these EDC, alterations in transcriptional and translational levels of proliferation and metastasis-related markers, including cyclin D1, p21, and cathepsin D, were determined. Data showed increase in expression of cyclin D1 and cathepsin D and decrease in p21 at both transcriptional and translational levels. However, BP1- or NP-induced alterations of these genes were blocked by ICI 182,780, suggesting that changes in expression of these genes may be regulated by an ER?-dependent pathway. In conclusion, BP1 and NP may accelerate growth of MCF-7 breast cancer cells by regulating cell cycle-related genes and promote cancer metastasis through amplification of cathepsin D. PMID:25849766
Transcellular transport of organic anions across a double-transfected Madin-Darby canine kidney II cell monolayer expressing both human organic anion-transporting polypeptide (OATP2/SLC21A6) and Multidrug resistance-associated protein 2 (MRP2/ABCC2).
Sasaki, Makoto; Suzuki, Hiroshi; Ito, Kousei; Abe, Takaaki; Sugiyama, Yuichi
Human organic anion transporting polypeptide 2 (OATP2/SLC21A6) and multidrug resistance-associated protein 2 (MRP2/ABCC2) play important roles in the vectorial transport of organic anions across hepatocytes. In the present study, we have established a double-transfected Madin-Darby canine kidney (MDCK II) cell monolayer, which expresses both OATP2 and MRP2 on basal and apical membranes, respectively. The basal-to-apical transport of 17 beta estradiol 17 beta-d-glucuronide (E(2)17 beta G), pravastatin, and leukotriene C(4) (LTC(4)), which are substrates of OATP2 and MRP2, was significantly higher than that in the opposite direction in the double-transfected cells. Such vectorial transport was also observed for taurolithocholate sulfate, which is transported by rat oatp1 and Mrp2. The K(m) values of E(2)17 beta G and pravastatin for the basal-to-apical flux were 27.9 and 24.3 microm, respectively, which were comparable with those reported for OATP2. Moreover, the MRP2-mediated export of E(2)17 beta G across the apical membrane was not saturated. In contrast, basal-to-apical transport of estrone-3-sulfate and dehydroepiandrosterone sulfate, which are significantly transported by OATP2, but not by MRP2, was not stimulated by MRP2 expression. The double-transfected MDCK II monolayer expressing both OATP2 and MRP2 may be used to analyze the hepatic vectorial transport of organic anions and to screen the transport profiles of new drug candidates. PMID:11748225
Antiestrogenic activity of 2,3,7,8-tetrachlorodibenzo-p-dioxin: Effect on expression of pS2, a prognostic marker for human breast cancer
Gillesby, B.E.; Wu, Z.F.; Zacharewski, T. [Univ. of Western Ontario, London, Ontario (Canada). Dept. of Pharmacology and Toxicology; Stanostefano, M.; Safe, S. [Texas A and M Univ., College Station, TX (United States). Dept. of Veterinary Physiology and Pharmacology
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds modulate endocrine systems by altering hormone synthesis, enhancing ligand metabolism and down-regulating receptor levels and binding activity. Previous studies have demonstrated that TCDD inhibits the 17{beta}-estradiol (E2)-induction of pS2, a prognostic marker for breast cancer. This effect occurs at the transcriptional level and is an Ah receptor-mediated process. Computer analysis of the regulatory region identified three dioxin response element (DRE)-like motifs each containing a perfectly conserved DRE core. In order to identify the motif which mediated this inhibition, transient transfection experiments were performed in MCF-7 human breast cancer cells using pS2-regulated luciferase reporter genes. Deletion analysis indicates that the DRE-like motif (IDRE) located at {minus}527 to {minus}514 is required for TCOD-mediated suppression of E2-induced reporter gene activity. The introduction of a point mutation within this core motif (T to C at position {minus}518) abolishes the suppressive effects, further supporting a role for the IDRE- in the antiestrogenic activity of TCDD. UV-induced protein-DNA cross-linking studies and gel retardation assays demonstrate that the IDRE could bind and compete with the consensus DRE for Ah receptor complex binding. These results suggest that Ah receptor complexes interact with a specific motif in the 51 regulatory region to suppress E2-induction of pS2 expression. Therefore, the inhibition of gene expression may also contribute to the antiestrogenic activities of TCOD and related compounds.
Evaluation of the disodium salt of 4,4'-diamino-2,2'-stilbene disulfonic acid for estrogenic activity.
Hostetler, K A; Leach, M W; Hyde, T E; Wei, L L
4,4'-Diamino-2,2'-stilbene disulfonic acid (DAS), a key intermediate in the synthesis of dyes and fluorescent whitening agents, has been purported to have weak estrogenic properties based on apparent structural similarity with diethylstibestrol (DES) and unsubstantiated reports of male reproductive dysfunction in an industrial setting. In weanling rats, high doses of DAS (300 mg/kg ip; 1000-3000 mg/kg oral) have been associated with modest increases in the uterus/body weight ratio (Smith & Quinn, 1992). In order to more directly and definitively determine if DAS possesses estrogenic activity, in vitro studies were conducted to establish its relative binding affinity to the human estrogen receptor (ER) in MCF-7 cells, a well-characterized breast cancer cell line. At concentrations approaching its solubility limit (10(-4) M), DAS failed to display [3H]-17beta-estradiol (E2) from the ER. In contrast, DES and E2 demonstrated characteristic competitive binding curves (50% displacement of 3H-E2 at 3.33 x 10(-9) and 1.33 x 10(-8) M, respectively). Parallel in vivo comparisons of DAS (10 or 30 mg/animal) and DES (1 or 3 microgram/animal) were also conducted to assess uterotropic effects. After three daily subcutaneous injections, DAS did not induce uterine weight gain. In contrast, DES consistently and markedly increased uterine weight and induced uterine water imbibition, with the latter effect being absent in DAS-treated rats. Under these experimental conditions, DAS was shown to possess negligible, if any, estrogenic activity, despite apparent structural similarity with known estrogens. PMID:8642622
Effects of culture conditions on estrogen-mediated hepatic in vitro gene expression and correlation to in vivo responses
Fong, C.J. [Department of Biochemistry and Molecular Biology, National Food Safety and Toxicology Center and Center for Integrative Toxicology, Michigan State University, 501 Biochemistry Building, Wilson Road, East Lansing, MI 48824-1319 (United States); Burgoon, L.D. [Department of Biochemistry and Molecular Biology, National Food Safety and Toxicology Center and Center for Integrative Toxicology, Michigan State University, 501 Biochemistry Building, Wilson Road, East Lansing, MI 48824-1319 (United States); Zacharewski, T.R. [Department of Biochemistry and Molecular Biology, National Food Safety and Toxicology Center and Center for Integrative Toxicology, Michigan State University, 501 Biochemistry Building, Wilson Road, East Lansing, MI 48824-1319 (United States)]. E-mail: firstname.lastname@example.com
Refinement of in vitro systems for predictive toxicology is important in order to develop high-throughput early toxicity screening assays and to minimize animal testing studies. This study assesses the ability of mouse Hepa-1c1c7 hepatoma cell model under differing culture conditions to predict in vivo estrogen-induced hepatic gene expression changes. Custom mouse cDNA microarrays were used to compare Hepa-1c1c7 temporal gene expression profiles treated with 10 nM 17{beta}-estradiol (E2) in serum-free and charcoal-stripped serum supplemented media at 1, 2, 4, 8, 12, and 24 h. Stripped serum supplemented media increased the number gene expression changes and overall responsiveness likely due to the presence of serum factors supporting proliferation and mitochondrial activity. Data from both experiments were compared to a gene expression time course study examining the hepatic effects of 100 {mu}g/kg 17{alpha}-ethynyl estradiol (EE) in C57BL/6 mice at 2, 4, 8, 12, 18, and 24 h. Only 18 genes overlapped between the serum-free and in vivo studies, whereas 238 genes were in common between Hepa-1c1c7 cells in stripped serum data and C57BL/6 liver samples. Stripped serum cultured cells exhibited E2-elicited gene expression changes associated with proliferation, cytoskeletal re-organization, cholesterol uptake and synthesis, increased fatty acid {beta}-oxidation, and oxidative stress, which correlated with in vivo hepatic responses. These results demonstrate that E2 treatment of Hepa-1c1c7 cells in serum supplemented media modulate responses in selected pathways which appropriately model estrogen-elicited in vivo hepatic responses.
Induction of endometrial adenocarcinomas in persistent estrous Donryu rats by a single intra-uterine administration of N-ethyl-N'-nitro-N-nitrosoguanidine.
Takahashi, M; Ando-Lu, J; Iijima, T; Ishihara, R; Imai, S; Kitamura, T; Wakabayashi, K; Maekawa, A
Induction of endometrial adenocarcinomas in persistent estrous Donryu rats by a single intra-uterine administration of N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) was examined. Female Donryu rats were divided into four groups at 7 weeks of age. Rats in Croup 1 were controls under a 12-h light/12-h dark regimen while Groups 2-4 were persistent estrous animals maintained under 24-h light conditions. At 10 weeks of age, rats in Group 1 and 2 were given a single intra-uterine administration of polyethylene glycol(PEG), and those in Groups 3 and 4 received ENNG(20 mg/kg body weight), dissolved in PEG, in the same manner. Group 4 rats also received an s.c. 17 beta-estradiol(E2) implant one week thereafter. At the termination of the experiment (week 42 after the ENNG-treatment), all surviving rats were killed and the development of uterine proliferative lesions assessed. All groups demonstrated hyperplasias, the incidence and severity being higher in ENNG-treated animals. The incidence of uterine adenocarcinomas in Group 2(2/20, 10%) was slightly higher than that in Group 1(0/16, 0%), although this difference was not significant. In Groups 3(7/19, 37%) and 4(6/20, 30%) statistically significant induction of adenocarcinomas was noted, two lesions in the latter case being very large with prominent invasion of tumor cells into the perimetrium. At 10 and 25 weeks after ENNG-treatment, the E2-progesterone(E2:P) ratios in Groups 2, 3 and 4 were significantly higher than in Group 1.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7772735
Microbiological hydroxylation of estradiol: formation of 2- and 4-hydroxyestradiol by Aspergillus alliaceus.
Williamson, J; Van Orden, D; Rosazza, J P
Microorganisms known to hydroxylate alkaloids, amino acids, and aromatic substrates were examined for their potential to hydroxylate 17 beta-estradiol and estrone. Thin-layer chromatography of fermentation extracts revealed a wide range of steroid products. Aspergillus alliaceus (UI 315) was the only culture capable of producing good yields of catechol estrogens with 17 beta-estradiol. The organism also transformed estrone but not to catechol products. Analytical experiments with high-performance liquid chromatography revealed that A. alliaceus formed 4- and 2-hydroxyestradiol with yields of 45 and 16%, respectively. A preparative-scale incubation was conducted in 2 liters of medium containing 1 g of 17 beta-estradiol as substrate. 4-Hydroxyestradiol was isolated and identified by proton nuclear magnetic resonance and high-resolution mass spectrometry. Ascorbic acid was added to microbial reaction mixtures as an antioxidant to prevent the decomposition of unstable catechol estrogen metabolites. The microbial transformation of 17 beta-estradiol by A. alliaceus provides an efficient one-step method for the preparation of catechol estrogens. PMID:3994364
Degradation of estrogens by Rhodococcus zopfii and Rhodococcus equi isolates from activated sludge in wastewater treatment plants.
Yoshimoto, Takeshi; Nagai, Fumiko; Fujimoto, Junji; Watanabe, Koichi; Mizukoshi, Harumi; Makino, Takashi; Kimura, Kazumasa; Saino, Hideyuki; Sawada, Haruji; Omura, Hiroshi
We have isolated four strains of Rhodococcus which specifically degrade estrogens by using enrichment culture of activated sludge from wastewater treatment plants. Strain Y 50158, identified as Rhodococcus zopfii, completely and rapidly degraded 100 mg of 17beta-estradiol, estrone, estriol, and ethinyl estradiol/liter, as demonstrated by thin-layer chromatography and gas chromatography-mass spectrometry analyses. Strains Y 50155, Y 50156, and Y 50157, identified as Rhodococcus equi, showed degradation activities comparable with that of Y 50158. Using the random amplified polymorphism DNA fingerprinting test, these three strains were confirmed to have been derived from different sources. R. zopfii Y 50158, which showed the highest activity among these four strains, revealed that the strain selectively degraded 17beta-estradiol during jar fermentation, even when glucose was used as a readily utilizable carbon source in the culture medium. Measurement of estrogenic activities with human breast cancer-derived MVLN cells showed that these four strains each degraded 100 mg of 17beta-estradiol/liter to 1/100 of the specific activity level after 24 h. It is thus suggested that these strains degrade 17beta-estradiol into substances without estrogenic activity. PMID:15345411
Estradiol-Induced Object Recognition Memory Consolidation Is Dependent on Activation of mTOR Signaling in the Dorsal Hippocampus
ERIC Educational Resources Information Center
Fortress, Ashley M.; Fan, Lu; Orr, Patrick T.; Zhao, Zaorui; Frick, Karyn M.
The mammalian target of rapamycin (mTOR) signaling pathway is an important regulator of protein synthesis and is essential for various forms of hippocampal memory. Here, we asked whether the enhancement of object recognition memory consolidation produced by dorsal hippocampal infusion of 17[Beta]-estradiol (E[subscript 2]) is dependent on mTOR…
Structure Determination and Characterization of the Vitamin B[superscript 6] Degradative Enzyme (E)-2-(Acetamidomethylene)succinate Hydrolase
McCulloch, Kathryn M.; Mukherjee, Tathagata; Begley, Tadhg P.; Ealick, Steven E. (Cornell); (TAM)
The gene identification and kinetic characterization of (E)-2-(acetamidomethylene)succinate (E-2AMS) hydrolase has recently been described. This enzyme catalyzes the final reaction in the degradation of vitamin B{sub 6} and produces succinic semialdehyde, acetate, ammonia, and carbon dioxide from E-2AMS. The structure of E-2AMS hydrolase was determined to 2.3 {angstrom} using SAD phasing. E-2AMS hydrolase is a member of the {alpha}/{beta} hydrolase superfamily and utilizes a serine/histidine/aspartic acid catalytic triad. Mutation of either the nucleophilic serine or the aspartate resulted in inactive enzyme. Mutation of an additional serine residue in the active site causes the enzyme to be unstable and is likely structurally important. The structure also provides insight into the mechanism of hydrolysis of E-2AMS and identifies several potential catalytically important residues.
Exogenous 17?-oestradiol (E2) modifies thymus growth and regionalization in European sea bass Dicentrarchus labrax.
Seemann, F; Knigge, T; Olivier, S; Monsinjon, T
The effect of 17?-oestradiol (E2) on the growth of the thymus and its regionalization into cortex and medulla was investigated in juvenile European sea bass Dicentrarchus labrax as they find themselves close to sources of oestrogenic pollution whilst residing in their estuarine nursery areas. While the exposure to 2, 20 and 200 ng l(-1) in 60 days post-hatch (dph) fish tended to cause a non-monotonous dose-response curve with a significant difference of the cortex size between lowest and highest exposures, the exposure to 20 ng l(-1) E2 from 90 dph onwards resulted in a distinct enlargement of the cortex. It is probable that the alteration of the cortex size also affects the T-cell differentiation and proliferation. PMID:25683570
E2 enzyme inhibition by stabilization of a low affinity interface with ubiquitin
St-Cyr, Daniel J.; Ziemba, Amy; Garg, Pankaj; Plamondon, Serge; Auer, Manfred; Sidhu, Sachdev; Marinier, Anne; Kleiger, Gary; Tyers, Mike; Sicheri, Frank
Weak protein interactions between ubiquitin and the ubiquitin-proteasome system (UPS) enzymes that mediate its covalent attachment to substrates serve to position ubiquitin for optimal catalytic transfer. We show that a small molecule inhibitor of the E2 ubiquitin conjugating enzyme Cdc34A, called CC0651, acts by trapping a weak interaction between ubiquitin and the E2 donor ubiquitin binding site. A structure of the ternary CC0651-Cdc34A-ubiquitin complex reveals that the inhibitor engages a composite binding pocket formed from Cdc34A and ubiquitin. CC0651 also suppresses the spontaneous hydrolysis rate of the Cdc34A-ubiquitin thioester, without overtly affecting the interaction between Cdc34A and the RING domain subunit of the E3 enzyme. Stabilization of the numerous other weak interactions between ubiquitin and UPS enzymes by small molecules may be a feasible strategy to selectively inhibit different UPS activities. PMID:24316736
Second-order Born calculation of coplanar symmetric (e, 2e) process on Mg
NASA Astrophysics Data System (ADS)
Zhang, Yong-Zhi; Wang, Yang; Zhou, Ya-Jun
The second-order distorted wave Born approximation (DWBA) method is employed to investigate the triple differential cross sections (TDCS) of coplanar doubly symmetric (e, 2e) collisions for magnesium at excess energies of 6 eV-20 eV. Comparing with the standard first-order DWBA calculations, the inclusion of the second-order Born term in the scattering amplitude improves the degree of agreement with experiments, especially for backward scattering region of TDCS. This indicates that the present second-order Born term is capable to give a reasonable correction to DWBA model in studying coplanar symmetric (e, 2e) problems of two-valence-electron target in low energy range.
E2/M1 Mixing Ratios for Gamma Transitions in 151Sm
NASA Astrophysics Data System (ADS)
Yamada, Shigeru
Measurements of gamma-gamma angular correlations in 151Sm following the decay of 151Pm have been made. A dual parameter (4096 ch.×4096 ch.) coincidence method with two Ge(Li) detectors was used. Multipole mixing ratios (E2/M1) of 17 gamma rays were deduced. Among them, six mixing ratios were determined for the first time. The parity of the 663.4 keV and 773.8 keV levels was assigned to be negative. Experimental large absolute values of E2/M1 mixing ratios of ?349.8{=}2.46±0.911.43, ?597.7{=}-4.30±19.42.74, ?636.1{=}-3.41±0.320.29 and ?669.2{=}-69.3±?58.9 agree with a calculation which takes vibrational components into account.
M1-E2 interference in the Zeeman spectra of Bi I
Werbowy, S.; Kwela, J. [Institute of Experimental Physics, University of Gdansk, Wita Stwosza 57, 80-952 Gdansk (Poland)
Studies of the M1-E2 interference effect in the mixed-type forbidden lines 461.5, 647.6, and 875.5 nm of Bi I are reported. A special computer program considering the interference effect was designed to obtain the predicted contours of the Zeeman structures of the lines. By variation of free parameters describing the line shapes and the electric-quadrupole admixtures, the calculated profiles were fitted to the recorded spectra. The E2 admixtures found are (7.84{+-}0.14)%, (17.5{+-}0.4)%, and (0.70{+-}0.11)% for the 461.5, 647.6, and 875.5 nm lines, respectively. Our results are compared with recent theories and other experiments.
Host-pathogen interactome analysis of Chikungunya virus envelope proteins E1 and E2.
Dudha, Namrata; Rana, Jyoti; Rajasekharan, Sreejith; Gabrani, Reema; Gupta, Amita; Chaudhary, Vijay Kumar; Gupta, Sanjay
The envelope proteins of Chikungunya virus (CHIKV) are known to play crucial roles in viral infection and spread. Although the role of envelope proteins in viral infection has been studied, the cellular interactors of these proteins are still elusive. In the present study, the ectodomains of CHIKV envelope proteins (E1 and E2) have been used for a high throughput yeast two-hybrid (Y2H) screening to identify the interacting host protein partners. Following a comparative analysis between the viral-host protein interaction data generated from Y2H and computational approach, five host proteins interacting with E1 and three host proteins interacting with E2 common to both datasets were identified. These associations were further verified independently by pull down and protein interaction ELISA. The identified interactions shed light on the possible cellular machinery that CHIKV might be employing during viral entry, trafficking, and evasion of immune system. PMID:25563600
Purification, crystallization and initial crystallographic characterization of brazil-nut allergen Ber?e?2
Guo, Feng; Jin, Tengchuan; Howard, Andrew; Zhang, Yu-Zhu
Peanut and tree-nut allergies have attracted considerable attention because of their frequency and their lifelong persistence. Brazil-nut (Bertholletia excelsa) allergies have been well documented and the 11S legumin-like seed storage protein Ber?e?2 (excelsin) is one of the two known brazil-nut allergens. In this study, Ber?e?2 was extracted from brazil-nut kernels and purified to high purity by crystalline precipitation and gel-filtration chromatography. Well diffracting single crystals were obtained using the hanging-drop vapour-diffusion method. A molecular-replacement structural solution has been obtained. Refinement of the structure is currently under way. PMID:18007055
Vector infection determinants of Venezuelan equine encephalitis virus reside within the E2 envelope glycoprotein.
Brault, Aaron C; Powers, Ann M; Weaver, Scott C
Epizootic subtype IAB and IC Venezuelan equine encephalitis viruses (VEEV) readily infect the epizootic mosquito vector Aedes taeniorhynchus. The inability of enzootic subtype IE viruses to infect this mosquito species provides a model system for the identification of natural viral determinants of vector infectivity. To map mosquito infection determinants, reciprocal chimeric viruses generated from epizootic subtype IAB and enzootic IE VEEV were tested for mosquito infectivity. Chimeras containing the IAB epizootic structural gene region and, more specifically, the IAB PE2 envelope glycoprotein E2 precursor gene demonstrated an efficient infection phenotype. Introduction of the PE2 gene from an enzootic subtype ID virus into an epizootic IAB or IC genetic backbone resulted in lower infection rates than those of the epizootic parent. The finding that the E2 envelope glycoprotein, the site of epitopes that define the enzootic and epizootic subtypes, also encodes mosquito infection determinants suggests that selection for efficient infection of epizootic mosquito vectors may mediate VEE emergence. PMID:12021373
Recoil Ion Momentum Spectroscopy: A Complementary Technique to (e,2e) and (e,3e)
L. Spielberger; O. Jagutzki; R. Dörner; K. Froschauer; A. Gensmantel; H. Schmidt-Böcking; J. Ullrich; U. Buck
\\u000a The recently developed technique of recoil-ion momentum spectroscopy (RIMS) has shown its ability to be a powerful tool for\\u000a the investigation of ionisation processes induced by the impact of fast ions. We show results for the ionisation dynamics\\u000a in the collision system 3 MeV protons on helium using this technique and demonstrate the relevance for similar (e,2e)-investigations.\\u000a Since our method
Examen Temps-Frquence. M2-Pro MISSAO/E2S, 29 novembre 2007
Examen Temps-Fréquence. M2-Pro MISSAO/E2S, 29 novembre 2007 1h30. Sans documents. NB: l'énoncé est signal peut-on (a) recentrer le signal en temps (i.e. avoir t = 0) ? (b) recentrer le signal en fréquence (i.e. avoir = 0) ? (c) recentrer le signal ŕ la fois en temps et en fréquence (i.e. avoir t = 0
E2F Repression by C\\/EBP? Is Required for Adipogenesis and Granulopoiesis In Vivo
Bo T. Porse; Thomas Ĺ. Pedersen; Xiufeng Xu; Bo Lindberg; Ulla M. Wewer; Lennart Friis-Hansen; Claus Nerlov
The C\\/EBP? transcription factor is required for differentiation of adipocytes and neutrophil granulocytes, and controls cellular proliferation in vivo. To address the molecular mechanisms of C\\/EBP? action, we have identified C\\/EBP? mutants defective in repression of E2F-dependent transcription and found them to be impaired in their ability to suppress cellular proliferation, and to induce adipocyte differentiation in vitro. Using targeted
Genetic Variation in the Prostaglandin E2 Pathway Is Associated with Primary Graft Dysfunction
Akimova, Tatiana; Kazi, Altaf; Shah, Rupal J.; Cantu, Edward; Feng, Rui; Levine, Matthew H.; Kawut, Steven M.; Meyer, Nuala J.; Lee, James C.; Hancock, Wayne W.; Aplenc, Richard; Ware, Lorraine B.; Palmer, Scott M.; Bhorade, Sangeeta; Lama, Vibha N.; Weinacker, Ann; Orens, Jonathan; Wille, Keith; Crespo, Maria; Lederer, David J.; Arcasoy, Selim; Demissie, Ejigayehu; Christie, Jason D.
Rationale: Biologic pathways with significant genetic conservation across human populations have been implicated in the pathogenesis of primary graft dysfunction (PGD). The evaluation of the role of recipient genetic variation in PGD has thus far been limited to single, candidate gene analyses. Objectives: We sought to identify genetic variants in lung transplant recipients that are responsible for increased risk of PGD using a two-phase large-scale genotyping approach. Methods: Phase 1 was a large-scale candidate gene association study of the multicenter, prospective Lung Transplant Outcomes Group cohort. Phase 2 included functional evaluation of selected variants and a bioinformatics screening of variants identified in phase 1. Measurements and Main Results: After genetic data quality control, 680 lung transplant recipients were included in the analysis. In phase 1, a total of 17 variants were significantly associated with PGD, four of which were in the prostaglandin E2 family of genes. Among these were a coding variant in the gene encoding prostaglandin E2 synthase (PTGES2; P = 9.3 × 10?5) resulting in an arginine to histidine substitution at amino acid position 298, and three variants in a block containing the 5? promoter and first intron of the PTGER4 gene (encoding prostaglandin E2 receptor subtype 4; all P < 5 × 10?5). Functional evaluation in regulatory T cells identified that rs4434423A in the PTGER4 gene was associated with differential suppressive function of regulatory T cells. Conclusions: Further research aimed at replication and additional functional insight into the role played by genetic variation in prostaglandin E2 synthetic and signaling pathways in PGD is warranted. PMID:24467603
RBP1 induces growth arrest by repression of E2F-dependent transcription
Albert Lai; Richard C Marcellus; Hughes B Corbeil; Philip E Branton
Growth arrest and cell cycle progression are regulated by the retinoblastoma tumour suppressor pRB and related proteins p130 and p107 that bind to and inhibit the E2F family of transcription factors. Although the precise mechanism of this inhibition remains to be established, previous studies indicated the presence of transcriptional repression activity in the `pocket' of RB family members. We show
A novel 3 volts-only, small sector erase, high density flash E2PROM
S. Kianian; A. Levi; D. Lee; Yaw-Wen Hu
A split gate Flash E2PROM memory cell with Fowler-Nordhiem tunneling erase, and high efficiency hot electron programming is presented. Gate current measurements show that one out of every 300 channel electrons is injected into the gate under worst case programming conditions. The greater efficiency of cell allows the use of small on-chip multipliers for single 3v Vcc operation. High cell
Performance Verification of the Astro-E2 X-ray spectrometer in the flight configuration
N Ota; K R Boyce; G V Brown; J Cottam; R Fujimoto; T Furusho; Y Ishisaki; R L Kelley; C A Kilbourne; D McCammon; K Mitsuda; U Morita; F S Porter; Y Takei; M Yamamoto
The X-ray Spectrometer (XRS) is a high resolution, non-dispersive cryogenic detector on board the X-ray satellite, Astro-E2 (Suzaku), which was successfully launched on July 10, 2005. The XRS achieves an energy resolution of 6 eV at 6 keV (FWHM) and covers a broad energy range of â 0.07-10 keV. The XRS will enable powerful plasma diagnostics of a variety of
Down regulation by iron of prostaglandin E2production by human synovial fibroblasts
Naoko Hisakawa; Koji Nishiya; Kiyoshi Tahara; Akinori Matsumori; Kozo Hashimoto
OBJECTIVETo examine the effect of iron on the prostaglandin (PG) E2 production by human synovial fibroblasts in vitro.METHODSHuman synovial fibroblasts were isolated from synovial tissue of rheumatoid arthritis (RA) and osteoarthritis (OA) patients and cultured in medium. Synovial fibroblasts were stimulated by human recombinant interleukin (IL) 1? (0.1–10 ng\\/ml) with or without ferric citrate (Fe-citrate, 0.01–1 mM). The amount of
Advanced Stirling Convertor (ASC-E2) Performance Testing at NASA Glenn Research Center
NASA Technical Reports Server (NTRS)
Oriti, Salvatore; Wilson, Scott
The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) has been supporting development of the Advanced Stirling Radioisotope Generator (ASRG) since 2006. A key element of the ASRG Project is providing life, reliability, and performance testing of the Advanced Stirling Convertor (ASC). For this purpose, four pairs of ASCs capable of operating to 850 C and designated with the model number ASC-E2, were delivered by Sunpower of Athens, OH, to GRC in 2010. The ASC-E2s underwent a series of tests that included workmanship vibration testing, performance mapping, and extended operation. Workmanship vibration testing was performed following fabrication of each convertor to verify proper hardware build. Performance mapping consisted of operating each convertor at various conditions representing the range expected during a mission. Included were conditions representing beginning-of-mission (BOM), end-of-mission (EOM), and fueling. This same series of tests was performed by Sunpower prior to ASC-E2 delivery. The data generated during the GRC test were compared to performance before delivery. Extended operation consisted of a 500-hour period of operation with conditions maintained at the BOM point. This was performed to demonstrate steady convertor performance following performance mapping. Following this initial 500-hour period, the ASC-E2s will continue extended operation, controller development and special durability testing, during which the goal is to accumulate tens of thousands of hours of operation. Data collected during extended operation will support reliability analysis. Performance data from these tests is summarized in this paper.
Advanced Stirling Convertor (ASC-E2) Performance Testing at NASA Glenn Research Center
NASA Technical Reports Server (NTRS)
Oriti, Salvatore; Wilson, Scott
The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) has been supporting development of the Advanced Stirling Radioisotope Generator (ASRG) since 2006. A key element of the ASRG Project is providing life, reliability, and performance testing of the Advanced Stirling Convertor (ASC). For this purpose, four pairs of ASCs capable of operating to 850 C and designated with the model number ASC-E2, were delivered by Sunpower of Athens, Ohio, to GRC in 2010. The ASC-E2s underwent a series of tests that included workmanship vibration testing, performance mapping, and extended operation. Workmanship vibration testing was performed following fabrication of each convertor to verify proper hardware build. Performance mapping consisted of operating each convertor at various conditions representing the range expected during a mission. Included were conditions representing beginning-of-mission (BOM), end-of-mission (EOM), and fueling. This same series of tests was performed by Sunpower prior to ASC-E2 delivery. The data generated during the GRC test were compared to performance before delivery. Extended operation consisted of a 500-hr period of operation with conditions maintained at the BOM point. This was performed to demonstrate steady convertor performance following performance mapping. Following this initial 500-hr period, the ASC-E2s will continue extended operation, controller development and special durability testing, during which the goal is to accumulate tens of thousands of hours of operation. Data collected during extended operation will support reliability analysis. Performance data from these tests is summarized in this paper.
Regulation of urea permeability in frog urinary bladder by prostaglandin E 2
Vera T. Bachteeva; Ekaterina M. Fock; Elena A. Lavrova; Elena V. Naboka; Rimma G. Parnova
The present study was performed to investigate the role of prostaglandin E2 (PGE2) in the regulation of urea transport in the frog urinary bladder, which is known to occur via a specialized arginine-vasotocin- (AVT-) regulated urea transporter. The bladders isolated from Rana temporaria L. were filled with amphibian Ringer solution containing 370 Bq\\/ml (0.01 µCi\\/ml) of [14C]urea, and urea permeability
E2\\/M1 Mixing Ratios for Gamma Transitions in 151Sm
Shigeru Yamada
Measurements of gamma-gamma angular correlations in 151Sm following the decay of 151Pm have been made. A dual parameter (4096 ch.×4096 ch.) coincidence method with two Ge(Li) detectors was used. Multipole mixing ratios (E2\\/M1) of 17 gamma rays were deduced. Among them, six mixing ratios were determined for the first time. The parity of the 663.4 keV and 773.8 keV levels
Development of the HXD anti counters onboard Astro-E2
Kazutaka Yamaoka; Masanori Ohno; Yukikatsu Terada; S. Hong; J. Kotoku; Y. Okada; A. Tsutsui; M. Mori; K. Makishima; M. Kokubun; T. Murakami; D. Yonetoku; M. Nomachi; T. Kamae; T. Takahashi; K. Nakazawa; M. Tashiro; I. Takahashi; S. Watanabe; Y. Fukazawa
The hard X-ray detector (HXD) is one of the three instruments onboard Japanese X-ray astronomy satellite Astro-E2 scheduled for launch in 2005. This mission is very unique in a point of having a lower detector background than any other past missions in the 10-600 keV range. In the HXD, the large and thick BGO crystal are used as active shields
Stress responses: the contribution of prostaglandin E2 and its receptors
Shuh Narumiya; Tomoyuki Furuyashiki
Stress is a state of physiological or psychological strain caused by adverse stimuli; responses to stress include activation of the sympathetic nervous system, glucocorticoid secretion and emotional behaviors. Prostaglandin E2 (PGE2), acting through its four receptor subtypes (EP1, EP2, EP3 and EP4), is involved in these stress responses. Studies of EP-selective drugs and mice lacking specific EPs have identified the
Effect of Ciprofloxacin-Induced Prostaglandin E2 on Interleukin18Treated Monocytes
Hideo Kohka Takahashi; Hiromi Iwagaki; Dong Xue; Goutarou Katsuno; Sachi Sugita; Kenji Mizuno; Shuji Mori; Shinya Saito; Tadashi Yoshino; Noriaki Tanaka; Masahiro Nishibori
Ciprofloxacin, a fluorinated 4-quinolone, is useful for the clinical treatment of infections due to its anti- bacterial properties and also modulates the immune response of monocytes isolated from human peripheral blood mononuclear cells. In the present study, we found that ciprofloxacin induced the production of prosta- glandin E2 in monocytes in a concentration-dependent manner regardless of the presence of interleukin-18
Multiple Members of the E2F Transcription Factor Family are the Products of Oncogenes
Gangfeng Xu; David M. Livingston; Wilhelm Krek
The retinoblastoma gene product (pRB) is a known tumor suppressor, capable of arresting growth in mid-to-late G_1. Part of its growth suppression action arises from interaction(s) with one or more members of the E2F family of transcription factors. These proteins most likely contribute to progression from G_o to S phase in mammalian cells, and pRB binding most likely inhibits aspects
Novel cellular interacting partners of the human papillomavirus 16 transcription\\/replication factor E2
Winifred Boner; Iain M Morgan
Human papillomaviruses (HPVs) are causative agents in a number of human diseases. HPV can be divided into two groups: low risk that cause diseases such as genital warts, and high risk that cause ano-genital cancers. Of the high-risk group, HPV16 is the most commonly found in cervical cancer. All HPV encode an E2 protein and this protein regulates transcription from,
Inhibition of the bovine papillomavirus E2 protein activity by peptide nucleic acid
Reet Kurg; Ülo Langel; Mart Ustav
The bovine papillomavirus type-1 E2 protein is the master regulator of the papillomavirus transcription and replication, the activity of which is regulated through sequence-specific DNA binding. Peptide nucleic acid (PNA) is a nucleic acid analogue, which associates with high affinity to complementary DNA, RNA or PNA, yielding in formation of stable complexes. The potential use of PNA as a sequence-specific
Microarray detection of E2F pathway activation and other targets in multiple sclerosis peripheral blood mononuclear cells
Antonio H Iglesias; Sandra Camelo; Daehee Hwang; Raul Villanueva; George Stephanopoulos; Fernando Dangond
We performed microarray analysis of peripheral blood mononuclear cells (PBMCs) from multiple sclerosis (MS) patients and detected a profile of immune cell activation, autoantigen upregulation, and enhanced E2F pathway transcription. Accordingly, E2f1-deficient mice manifested only mild disability upon induction of experimental autoimmune encephalomyelitis (EAE). Furthermore, PBMCs from Avonex-treated patients had lower expression of E2F targets. The profile was enriched in
Novel E2F decoy oligodeoxynucleotides inhibit in vitro vascular smooth muscle cell proliferation and in vivo neointimal hyperplasia
J D Ahn; R Morishita; Y Kaneda; H S Kim; Y-C Chang; K-U Lee; J-Y Park; H W Lee; Y-H Kim; I-K Lee
The transcription factor, E2F, plays a critical role in the trans-activation of several genes involved in cell cycle regulation. Previous studies showed that the transfection of cis element double-stranded decoy oligodeoxynucleotides (ODNs) corresponding to E2F binding sites inhibited the proliferation of vascular smooth muscle cells (VSMCs) and neointimal hyperplasia in injured vessels. We have developed a novel E2F decoy ODN
A specific subset of E2 ubiquitin-conjugating enzymes regulate Parkin activation and mitophagy differently.
Fiesel, Fabienne C; Moussaud-Lamodičre, Elisabeth L; Ando, Maya; Springer, Wolfdieter
Loss-of-function mutations in the genes encoding PINK1 and Parkin (also known as PARK2) are the most common causes of recessive Parkinson's disease. Both together mediate the selective degradation of mitochondrial proteins and whole organelles via the proteasome and the autophagy-lysosome pathway (mitophagy). The mitochondrial kinase PINK1 activates and recruits the E3 ubiquitin ligase Parkin to de-energized mitochondria. However, the cognate E2 co-enzymes of Parkin in this ubiquitin-dependent pathway have not been investigated. Here, we discovered a total of four E2s that either positively or negatively regulate the activation, translocation and enzymatic functions of Parkin during mitochondrial quality control. UBE2D family members and UBE2L3 redundantly charged the RING-HECT hybrid ligase Parkin with ubiquitin, resulting in its initial activation and translocation to mitochondria. UBE2N, however, primarily operated through a different mechanism in order to mediate the proper clustering of mitochondria, a prerequisite for degradation. Strikingly, in contrast to UBE2D, UBE2L3 and UBE2N, depletion of UBE2R1 resulted in enhanced Parkin translocation and clustering upon mitochondrial uncoupling. Our study uncovered redundant, cooperative or antagonistic functions of distinct E2 enzymes in the regulation of Parkin and mitophagy that might suggest a putative role in Parkinson's disease pathogenesis. PMID:24928900
Investigation into the B(E2) anomaly in {sup 144}Nd using Coulomb excitation
Fitzpatrick, C. R. [WNSL, Yale University, New Haven, Connecticut 06511 (United States); University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Werner, V.; Casten, R. F.; Williams, E.; Ai, H.; Heinz, A.; McCutchan, E. A.; Meyer, D. A.; Novitski, E.; Qian, J.; Winkler, R. [WNSL, Yale University, New Haven, Connecticut 06511 (United States); Beausang, C. W. [WNSL, Yale University, New Haven, Connecticut 06511 (United States); University of Richmond, Richmond, Virginia 23173 (United States); Cakirli, R. B. [WNSL, Yale University, New Haven, Connecticut 06511 (United States); Istanbul University, Department of Physics (Turkey); Guerdal, G. [WNSL, Yale University, New Haven, Connecticut 06511 (United States); Clark University, Worcester, Massachusetts 01610 (United States)
The ratio of B(E2) strengths between the lowest lying members of the ground state band in {sup 144}Nd, B{sub 4/2}=B(E2;4{sub 1}{sup +}{yields}2{sub 1}{sup +})/B(E2;2{sub 1}{sup +}{yields}0{sub 1}{sup +}), which is used to quantify collectivity in nonmagic nuclei, has been remeasured by means of Coulomb excitation. Ambiguities in literature values for this ratio have been resolved. The results are discussed in terms of the interplay of collective and single-particle degrees of freedom, and in the context of the formation of collective structures in the A=140 mass region, and more generally near (sub)shell closures. In addition, the B{sub 4/2} ratio of {sup 148}Sm has been remeasured, and the quadrupole moment of the 4{sub 1}{sup +} state is found to be on the order of 1 e b.
Sequence Variation in the E2-Binding Domain of HPV16 and Biological Function Evaluation in Tunisian Cervical Cancers
Kahla, Saloua; Kochbati, Lotfi; Hammami, Samia; Chanoufi, Mohamed Badis; Maalej, Mongi; Oueslati, Ridha
HPV16 E2 variants have different effects on the transcriptional activity of the LCR. In this study, we examined the nucleotide and amino acid sequence variation within the HPV16 E2 gene and to correlate with disease progression. E2 gene disruption was detected by PCR amplification of the entire E2 gene using a single set of primers. Nucleotide variations were analyzed by bidirectional sequencing. mRNA expression patterns of E6 and E7 gene transcripts were evaluated by a reverse transcriptase-PCR method (RT-PCR). The detection of intact E2 genes was significantly higher among controls than cases (81.8% versus 37.5%, resp., P < 0.05). Among the E subgroup, variation at position 3684 C>A results in the amino acid substitution T310K and was more common among the E2 undisrupted cases (7/9; 77.7%), compared to controls (2/9; 22.2%). In addition, specific sequence variations identified in the E2 ORF at positions 3684 C>A were associated with increased viral oncogenes E6-E7 production. Besides HPV16 E2 disruption, the 3684 C>A variation within undisrupted E2 genes could be involved in an alternative mechanism for deregulating the expression of the HPV16 E6 and E7 oncogenes and appears to be a major factor contributing to the development of cervical cancer in Tunisian women. PMID:25032221
Sequence variation in the E2-binding domain of HPV16 and biological function evaluation in Tunisian cervical cancers.
Kahla, Saloua; Kochbati, Lotfi; Hammami, Samia; Chanoufi, Mohamed Badis; Maalej, Mongi; Oueslati, Ridha
HPV16 E2 variants have different effects on the transcriptional activity of the LCR. In this study, we examined the nucleotide and amino acid sequence variation within the HPV16 E2 gene and to correlate with disease progression. E2 gene disruption was detected by PCR amplification of the entire E2 gene using a single set of primers. Nucleotide variations were analyzed by bidirectional sequencing. mRNA expression patterns of E6 and E7 gene transcripts were evaluated by a reverse transcriptase-PCR method (RT-PCR). The detection of intact E2 genes was significantly higher among controls than cases (81.8% versus 37.5%, resp., P < 0.05). Among the E subgroup, variation at position 3684 C>A results in the amino acid substitution T310K and was more common among the E2 undisrupted cases (7/9; 77.7%), compared to controls (2/9; 22.2%). In addition, specific sequence variations identified in the E2 ORF at positions 3684 C>A were associated with increased viral oncogenes E6-E7 production. Besides HPV16 E2 disruption, the 3684 C>A variation within undisrupted E2 genes could be involved in an alternative mechanism for deregulating the expression of the HPV16 E6 and E7 oncogenes and appears to be a major factor contributing to the development of cervical cancer in Tunisian women. PMID:25032221
p1 RJM 4/05/07 CY3E2 Env FB Sys 2005 Exam Dr Richard Mitchell 2007
Mitchell, Richard
p1 RJM 4/05/07 CY3E2 Env FB Sys 2005 Exam © Dr Richard Mitchell 2007 CY3E2 2005 Exam 3. Host values of H and S. [6] #12;p2 RJM 4/05/07 CY3E2 Env FB Sys 2005 Exam © Dr Richard Mitchell 2007 S +- ++ +- -- -- dS/dt=0 dH/dt=0 9 H 10 S -+ 5 2 5 2 #12;p3 RJM 4/05/07 CY3E2 Env FB Sys 2005 Exam © Dr Richard
Targeted gene mutation of E2F1 evokes age-dependent synaptic disruption and behavioral deficits
Ting, Jenhao H.; Marks, David R.; Schleidt, Stephanie S.; Wu, Joanna N.; Zyskind, Jacob W.; Lindl, Kathryn A.; Blendy, Julie A.; Pierce, R. Christopher; Jordan-Sciutto, Kelly L.
Aberrant expression and activation of the cell cycle protein E2F1 in neurons has been implicated in many neurodegenerative diseases. As a transcription factor regulating G1 to S phase progression in proliferative cells, E2F1 is often upregulated and activated in models of neuronal death. However, despite its well studied functions in neuronal death, little is known regarding the role of E2F1 in the mature brain. In the present study, we used a combined approach to study the effect of E2F1 gene disruption on mouse behavior and brain biochemistry. We identified significant age-dependent olfactory and memory related deficits in E2f1 mutant mice. In addition, we found that E2F1 exhibits punctated staining and localizes closely to the synapse. Furthermore, we found a mirroring age-dependent loss of postsynaptic protein-95 in the hippocampus and olfactory bulb as well as a global loss of several other synaptic proteins. Coincidently, E2F1 expression is significantly elevated at the ages in which behavioral and synaptic perturbations were observed. Lastly, we show that deficits in adult neurogenesis persist late in aged E2f1 mutant mice which may partially contribute to the behavior phenotypes. Taken together, our data suggest that the disruption of E2F1 function leads to specific age-dependent behavioral deficits and synaptic perturbations. PMID:24460902
Expression of the surface glycoprotein E2 of Bovine viral diarrhea virus by recombinant vesicular stomatitis virus.
Köhl, Wiebke; Gröne, Andrea; Moennig, Volker; Herrler, Georg
This study analysed the transport behaviour of the glycoprotein E2 of Bovine viral diarrhea virus (BVDV) expressed from recombinant vesicular stomatitis virus (rVSV). E2 protein was found to be retained at an intracellular compartment. A chimeric protein containing the membrane anchor and cytoplasmic tail of the VSV G protein, E2-G(MT), was transported to the cell surface. Only the latter protein was incorporated into rVSV particles in significant amounts. A soluble form of E2 lacking the membrane anchor, E2(MTdel), appeared to be affected in conformational stability. In contrast to both membrane-anchored forms of E2, expression of the soluble form was detectable only by immunofluorescence microscopy but not by Western blotting. These results are in agreement with reports of intracellular retention of the E2 protein due to a retention signal in the membrane anchor. However, in another analysis of E2 expressed from rVSV, E2 protein was reported to be transported to the cell surface and incorporated into VSV particles [Grigera, P. R., Marzocca, M. P., Capozzo, A. V. E., Buonocore, L., Donis, R. O. & Rose, J. K. (2000). Virus Res 69, 3-15]. Reasons for these contradictory results are discussed. PMID:17170448
Dose-response effects of estrogenic mycotoxins (zearalenone, alpha- and beta-zearalenol) on motility, hyperactivation and the acrosome reaction of stallion sperm
Background The aim of this study was to investigate the in vitro effects of the Fusarium fungus-derived mycotoxin, zearalenone and its derivatives alpha-zearalenol and beta-zearalenol on motility parameters and the acrosome reaction of stallion sperm. Since the toxic effects of zearalenone and its derivatives are thought to result from their structural similarity to 17beta-estradiol, 17beta-estradiol was used as a positive control for 'estrogen-like' effects. Methods Stallion spermatozoa were exposed in vitro to zearalenone, alpha-zearalenol, beta-zearalenol or 17beta-estradiol at concentrations ranging from 1 pM - 0.1 mM. After 2 hours exposure, motility parameters were evaluated by computer-assisted analysis, and acrosome integrity was examined by flow cytometry after staining with fluoroscein-conjugated peanut agglutinin. Results Mycotoxins affected sperm parameters only at the highest concentration tested (0.1 mM) after 2 hours exposure. In this respect, all of the compounds reduced the average path velocity, but only alpha-zearalenol reduced percentages of motile and progressively motile sperm. Induction of motility patterns consistent with hyperactivation was stimulated according to the following rank of potency: alpha-zearalenol >17beta-estradiol > zearalenone = beta-zearalenol. The hyperactivity-associated changes observed included reductions in straight-line velocity and linearity of movement, and an increase in the amplitude of lateral head displacement, while curvilinear velocity was unchanged. In addition, whereas alpha- and beta- zearalenol increased the percentages of live acrosome-reacted sperm, zearalenone and 17beta-estradiol had no apparent effect on acrosome status. In short, alpha-zearalenol inhibited normal sperm motility, but stimulated hyperactive motility in the remaining motile cells and simultaneously induced the acrosome reaction. Beta-zearalenol induced the acrosome reaction without altering motility. Conversely, zearalenone and 17beta-estradiol did not induce the acrosome reaction but induced hyperactive motility albeit to a different extent. Conclusions Apparently, the mycotoxin zearalenone has 17beta-estradiol-like estrogenic activity that enables it to induce hyperactivated motility of equine sperm cells, whereas the zearalenol derivatives induce premature completion of the acrosome reaction and thereby adversely affect stallion sperm physiology. The alpha form of zearalenol still possessed the estrogenic ability to induce hyperactivated motility, whereas its beta stereo-isomere had lost this property. PMID:21970729
Future Climate Change Simulated By Giss ModelE2 Under Representative Concentration Pathways
NASA Astrophysics Data System (ADS)
Nazarenko, L.; Tausnev, N.; Schmidt, G. A.
We examine the anthropogenically forced climate response for the twenty first century representative concentration pathway emission scenarios and their extensions for the period 2101-2500. The experiments were performed with ModelE2, a new version of the NASA Goddard Institute for Space Sciences coupled general circulation model that includes three different versions for the atmospheric composition components: a non-interactive version (NINT) with prescribed composition and a tuned aerosol indirect effect (AIE), the TCAD version with fully interactive aerosols, whole-atmosphere chemistry and the tuned AIE , and the TCADI version which further includes a parameterized first indirect aerosol effect on clouds. Each atmospheric version is coupled to two different ocean general circulation models: the Russell ocean model (GISS-E2-R) and HYCOM (GISS-E2-H). By 2100, global mean warming in the RCP scenarios ranges from 1.0şC to 4.5şC relative to 1850-1860 mean temperature in the historical simulations. In the RCP2.6 scenario, the surface warming in all simulations stays below a 2°C threshold at the end of the twenty-first century. For RCP8.5, the range is 3.5-4.5şC at 2100. Decadally averaged sea ice area changes are highly correlated to global mean surface air temperature anomalies and show steep declines in both hemispheres, with a larger sensitivity during winter months. By the year 2500, there are complete recoveries of the globally averaged surface air temperature for all versions of the GISS climate model in the low forcing scenario RCP2.6. TCADI simulations show enhanced warming due to greater sensitivity to CO2, aerosol effects and greater methane feedbacks. Both coupled models have decreases in the Atlantic overturning streamfunction by 2100. In RCP2.6 there is a complete recovery of the Atlantic overturning stream function by the year 2500 while with scenario RCP8.5. E2-R climate model produces a complete shutdown of the Atlantic overturning in the RCP8.5 while it reaches the equilibrium state of 35-40% of the control simulation in the E2-H model by the end of 25th century.
Downregulation of thymidylate synthase and E2F1 by arsenic trioxide in mesothelioma.
Lam, Sze-Kwan; Li, Yuan-Yuan; Zheng, Chun-Yan; Ho, James Chung-Man
Malignant pleural mesothelioma is a global health issue. Arsenic trioxide (ATO) has been shown to suppress thymidylate synthase (TYMS) in lung adenocarcinoma and colorectal cancer, and induce apoptosis in acute promyelocytic leukemia. With TYMS as a putative therapeutic target, the effect of ATO in mesothelioma was therefore studied. A panel of 5 mesothelioma cell lines was used to study the effect of ATO on cell viability, protein expression, mRNA expression and TYMS activity by MTT assay, western blot, qPCR and tritium-release assay, respectively. The knockdown of TYMS and E2F1 was performed with a specific siRNA. Phosphatidylserine externalization and mitochondrial membrane depolarization were measured by Annexin V and JC-1 staining respectively. The in vivo effect of ATO was studied using a nude mouse xenograft model. Application of ATO demonstrated anticancer effects in the cell line model with clinically achievable concentrations. Downregulation of TYMS protein (except H226 cells and 1.25 µM ATO in H2052 cells) and mRNA expression (H28 cells), pRB1 (H28 cells) and E2F1 and TYMS activity (except H226 cells) were also evident. E2F1 knockdown decreased cell viability more significantly than TYMS knockdown. In general, thymidine kinase 1, ribonucleotide reductase M1, c-myc and skp2 were downregulated by ATO. p-c-Jun was downregulated in H28 cells while upregulated in 211H cells. Phosphatidylserine externalization, mitochondrial membrane depolarization, downregulation of Bcl-2 and Bcl-xL, and upregulation of Bak and cleaved caspase-3 were observed. In the H226 xenograft model, the relative tumor growth was aborted, and E2F1 was downregulated while cleaved caspase-3 was elevated and localized to the nucleus in the ATO treatment group. ATO has potent antiproliferative and cytotoxic effects in mesothelioma in vitro and in vivo, partially mediated through E2F1 targeting (less effect through TYMS targeting). There is sound scientific evidence to support the clinical application of ATO in treatment of mesothelioma. PMID:25335113
The prostaglandin E2 receptor EP4 is integral to a positive feedback loop for prostaglandin E2 production in human macrophages infected with Mycobacterium tuberculosis.
Nishimura, Tomoyasu; Zhao, Xiaomin; Gan, Huixian; Koyasu, Shigeo; Remold, Heinz G
Prostaglandin E2 (PGE2) is an important biological mediator involved in the defense against Mycobacterium tuberculosis (Mtb) infection. Previously, we reported that in macrophages (M?s), infection with avirulent Mtb H37Ra resulted in inhibition of necrosis by an inhibitory effect on mitochondrial permeability transition via the PGE2 receptor EP2. However, human M?s also express EP4, a PGE2 receptor functionally closely related to EP2 that also couples to stimulatory guanine nucleotide binding protein, but the functional differences between EP2 and EP4 in Mtb-infected M?s have been unclear. EP4 antagonist addition to H37Ra-infected M?s inhibited the expression of cyclooxygenase 2 (COX2) and microsomal prostaglandin E synthase-1 (mPGES-1), which are involved in PGE2 production. Moreover, H37Ra infection induced PGE2 production through the Toll-like receptor (TLR) 2/p38 mitogen-activated protein kinase (MAPK) signaling pathway. Induction of COX2 and mPGES-1 expression by TLR2 stimulation or Mtb infection was increased after additional stimulation with EP4 agonist. Hence, in Mtb-infected M?s, PGE2 production induced by pathogen recognition receptors/p38 MAPK signaling is up-regulated by EP4-triggered signaling to maintain an effective PGE2 concentration. PMID:23759445
PPAR gene level differently affects lipid metabolism and inflammation in apolipoprotein E2 knock-in mice
Paris-Sud XI, Université de
1 PPAR gene level differently affects lipid metabolism and inflammation in apolipoprotein E2 knock metabolism and inflammation. PPAR is activated by fibrates, hypolipidemic drugs used in the treatment steatosis and inflammation compared to PPAR+/+ and PPAR+/- apoE2-KI mice, indicating a role of PPAR in liver
11 CFR 101.2 - Candidate as agent of authorized committee (2 U.S.C. 432(e)(2)).
Code of Federal Regulations, 2013 CFR
...agent of authorized committee (2 U.S.C. 432(e)(2)). 101.2 Section...CANDIDATE STATUS AND DESIGNATIONS (2 U.S.C. 432(e)) § 101.2 Candidate as agent of authorized committee (2 U.S.C. 432(e)(2)). (a) Any...
11 CFR 101.2 - Candidate as agent of authorized committee (2 U.S.C. 432(e)(2)).
Code of Federal Regulations, 2014 CFR
...agent of authorized committee (2 U.S.C. 432(e)(2)). 101.2 Section...CANDIDATE STATUS AND DESIGNATIONS (2 U.S.C. 432(e)) § 101.2 Candidate as agent of authorized committee (2 U.S.C. 432(e)(2)). (a) Any...
11 CFR 101.2 - Candidate as agent of authorized committee (2 U.S.C. 432(e)(2)).
Code of Federal Regulations, 2012 CFR
...agent of authorized committee (2 U.S.C. 432(e)(2)). 101.2 Section...CANDIDATE STATUS AND DESIGNATIONS (2 U.S.C. 432(e)) § 101.2 Candidate as agent of authorized committee (2 U.S.C. 432(e)(2)). (a) Any...
Functional p53 can modulate the relationship between E2F-1 expression and tumor kinetics in Hodgkin lymphoma.
Georgiadi, Eleni C; Dimtsas, Georgios S; Vassilakopoulos, Theodoros P; Pangalis, Gerassimos A; Kittas, Christos; Doussis-Anagnostopoulou, Ipatia A
E2F-1 is the best-described member of the E2F family of transcriptional factors and is particularly interesting in view of its often opposing roles. Our purpose was to examine the immunohistochemical expression of E2F-1 in Hodgkin lymphoma (HL) and to correlate it with proliferation and apoptosis of the tumor, clinicopathological parameters and patient outcome, as well as with expression of the downstream molecules p53 and p21. The median percentage of E2F-1-expressing Hodgkin Reed-Sternberg (HRS) cells was 80.2%. A significant positive correlation was found between expression of E2F-1 and p53 (p = 0.034). Following stratification of our cases, within the group harboring functional p53, a statistically significant inverse correlation was identified between E2F-1 and Topo IIa (p = 0.019). E2F-1 is up-regulated in the context of HL and its expression is inversely associated with proliferation. It seems that functional p53 can modulate the relationship between E2F-1 expression and tumor kinetics in HL. PMID:24925209
Structure of an E3:E2~Ub complex reveals an allosteric mechanism shared among RING/U-box ligases
Pruneda, Jonathan N.; Littlefield, Peter J.; Soss, Sarah E.; Nordquist, Kyle A.; Chazin, Walter J.; Brzovic, Peter S.; Klevit, Rachel E.
Despite the widespread importance of RING/U-box E3 ubiquitin ligases in ubiquitin (Ub) signaling, the mechanism by which this class of enzymes facilitates Ub transfer remains enigmatic. Here we present a structural model for a RING/U-box E3:E2~Ub complex poised for Ub transfer. The model and additional analyses reveal that E3 binding biases dynamic E2~Ub ensembles toward closed conformations with enhanced reactivity for substrate lysines. We identify a key hydrogen bond between a highly conserved E3 sidechain and an E2 backbone carbonyl, observed in all structures of active RING/U-Box E3/E2 pairs, as the linchpin for allosteric activation of E2~Ub. The conformational biasing mechanism is generalizable across diverse E2s and RING/U-box E3s, but is not shared by HECT-type E3s. The results provide a structural model for a RING/U-box E3:E2~Ub ligase complex and identify the long sought-after source of allostery for RING/U-Box activation of E2~Ub conjugates. PMID:22885007
Momentum Profile and Final Correlation Effects of Iso-butane Inner Valence by Binary (e, 2e) Spectroscopy
Wang, Yayu
Momentum Profile and Final Correlation Effects of Iso-butane Inner Valence by Binary (e, 2e Momentum Profile and Final Correlation Effects of Iso-butane Inner Valence by Binary (e, 2e) Spectroscopy) The binding energy spectra and the momentum distributions of the valence orbitals of iso-butane, also known
(e,2e) study of two-center interference effects in the ionization of N2 L. R. Hargreaves,1
Wang, Yayu
effects in triply differential cross sections TDCS , using the e,2e technique. An e,2e measurement requires the detection of both the ioniz- ing and ejected electron, in time coincidence. Hence, the TDCS by the integration of the TDCS over the momentum of one of the two final state continuum particles. Since integration
Recombinant pestivirus E2 glycoproteins prevent viral attachment to permissive and non permissive cells with different efficiency.
Asfor, A S; Wakeley, P R; Drew, T W; Paton, D J
Bovine viral diarrhoea virus (BVDV) is an economically important animal pathogen, which like other pestiviruses has similar molecular biological features to hepaciviruses, including human Hepatitis C virus. The pestivirus E2 glycoproteins are the major target for virus-neutralising antibodies, as well as playing a role in receptor binding and host range restriction. In this study, recombinant E2 glycoproteins (rE2) derived from three different pestivirus species were examined for their inhibitory effects on pestivirus infectivity in cell culture. Histidine-tagged rE2 glycoproteins of BVDV type 2 strain 178003, BVDV type 1 strain Oregon C24V and CSFV strain Alfort 187 were produced in Spodoptera frugiperda insect cells and purified under native conditions. The ability of rE2 glycoprotein to inhibit the infection of permissive cells by both homologous and heterologous virus was compared, revealing that the inhibitory effects of rE2 glycoproteins correlated with the predicted similarity of the E2 structures in the recombinant protein and the test virus. This result suggests that the sequence and structure of E2 are likely to be involved in the host specificity of pestiviruses at their point of uptake into cells. PMID:24874197
Mutations in Drosophila DP and E2F distinguish G1–S progression from an associated transcriptional?program
Royzman, Irena; Whittaker, Allyson J.; Orr-Weaver, Terry L.
The E2F transcription factor, a heterodimer of E2F and DP subunits, is capable of driving the G1–S transition of the cell cycle. However, mice in which the E2F-1 gene had been disrupted developed tumors, suggesting a negative role for E2F in controlling cell proliferation in some tissues. The consequences of disrupting the DP genes have not been reported. We screened for mutations that disrupt G1–S transcription late in Drosophila embryogenesis and identified five mutations in the dDP gene. Although mutations in dDP or dE2F nearly eliminate E2F-dependent G1–S transcription, S-phase still occurs. Cyclin E has been shown to be essential for S-phase in late embryogenesis, but in dDP and dE2F mutants the peaks of G1–S transcription of cyclin E are missing. Thus, greatly reduced levels of cyclin E transcript suffice for DNA replication until late in development. Both dDP and dE2F are necessary for viability, and mutations in the genes cause lethality at the late larval/pupal stage. The mutant phenotypes reveal that both genes promote progression of the cell cycle. PMID:9271122
A comprehensive framework of E2–RING E3 interactions of the human ubiquitin–proteasome system
van Wijk, Sjoerd J L; de Vries, Sjoerd J; Kemmeren, Patrick; Huang, Anding; Boelens, Rolf; Bonvin, Alexandre M J J; Timmers, H Th Marc
Covalent attachment of ubiquitin to substrates is crucial to protein degradation, transcription regulation and cell signalling. Highly specific interactions between ubiquitin-conjugating enzymes (E2) and ubiquitin protein E3 ligases fulfil essential roles in this process. We performed a global yeast-two hybrid screen to study the specificity of interactions between catalytic domains of the 35 human E2s with 250 RING-type E3s. Our analysis showed over 300 high-quality interactions, uncovering a large fraction of new E2–E3 pairs. Both within the E2 and the E3 cohorts, several members were identified that are more versatile in their interaction behaviour than others. We also found that the physical interactions of our screen compare well with reported functional E2–E3 pairs in in vitro ubiquitination experiments. For validation we confirmed the interaction of several versatile E2s with E3s in in vitro protein interaction assays and we used mutagenesis to alter the E3 interactions of the E2 specific for K63 linkages, UBE2N(Ubc13), towards the K48-specific UBE2D2(UbcH5B). Our data provide a detailed, genome-wide overview of binary E2–E3 interactions of the human ubiquitination system. PMID:19690564
Steroid determination in fish plasma using capillary electrophoresis.
Bykova, Liliya; Archer-Hartmann, Stephanie A; Holland, Lisa A; Iwanowicz, Luke R; Blazer, Vicki S
A capillary separation method that incorporates pH-mediated stacking is employed for the simultaneous determination of circulating steroid hormones in plasma from Perca flavescens (yellow perch) collected from natural aquatic environments. The method can be applied to separate eight steroid standards: progesterone, 17alpha,20beta-dihydroxypregn-4-en-3-one, 17alpha-hydroxyprogesterone, testosterone, estrone, 11-ketotestosterone, ethynyl estradiol, and 17beta-estradiol. Based on screening of plasma, the performance of the analytical method was determined for 17alpha,20beta-dihydroxypregn-4-en-3-one, testosterone, 11-ketotestosterone, and 17beta-estradiol. The within-day reproducibility in migration time for these four steroids in aqueous samples was < or =2%. Steroid quantification was accomplished using a calibration curve obtained with external standards. Plasma samples from fish collected from the Choptank and Severn Rivers, Maryland, USA, stored for up to one year were extracted with ethyl acetate and then further processed with anion exchange and hydrophobic solid phase extraction cartridges. The recovery of testosterone and 17beta-estradiol from yellow perch plasma was 84 and 85%, respectively. Endogenous levels of testosterone ranged from 0.9 to 44 ng/ml, and when detected 17alpha,20beta-dihydroxypregn-4-en-3-one ranged from 5 to 34 ng/ml. The reported values for testosterone correlated well with the immunoassay technique. Endogenous concentrations of 17beta-estradiol were < or =1.7 ng/ml. 11-Ketotestosterone was not quantified because of a suspected interferant. Higher levels of 17alpha,20beta-dihydroxypregn-4-en-3-one were found in male and female fish in which 17beta-estradiol was not detected. Monitoring multiple steroids can provide insight into hormonal fluctuations in fish. PMID:20821652
Inhibition of egg production in zebrafish by fluoxetine and municipal effluents: a mechanistic evaluation.
Lister, Andrea; Regan, Christine; Van Zwol, Jessica; Van Der Kraak, Glen
This study explored the impact of nominal concentrations of ethinylestradiol (EE(2); 10ng/L), fluoxetine (FLU; 0.32, 3.2, 32microg/L), and 1-50% treated municipal effluent on reproduction and liver function in sexually mature female zebrafish over a 7-day period. Compared with the control groups, FLU (32microg/L) and 50% effluent treatment significantly reduced the average eggs spawned by approximately 4.5 and 2 fold, respectively. FLU also decreased ovarian levels of 17beta-estradiol (E(2)) without affecting the gonadosomatic indices of the fish. The expression of ovarian genes involved in the production of prostaglandins, steroid biosynthesis, and gonadotropin receptors were quantified to determine a potential mechanism underlying the reduced egg production in FLU and effluent exposed fish. Quantitative real-time PCR analysis determined that ovarian aromatase, follicle stimulating hormone receptor (FSHr), and luteinizing hormone receptor (LHr) gene expression were significantly reduced by FLU suggesting that disruptions to the synthesis of ovarian steroids and the actions of gonadotropins may underlie the negative influence of FLU on ovarian E(2) and spawning levels. Potential mechanisms involved in the modest effects of the effluent on reproduction remain unknown, but the elevated levels of total ammonia and nitrite in the 50% effluent treatment groups compared with the other treatments should not be discounted. Liver expression of CYP3A65 was significantly induced by all treatments of effluent, while EE(2) caused a reduction in the expression levels of CYP1A1, PXR, and CYP3A65. The results of the present study suggest that SSRI may disrupt reproductive functioning at concentrations greater than those found in receiving environments; yet, more research is warranted into to the possible effects of low levels of synthetic estrogens on liver function in exposed fish, particularly the PXR-CYP3A pathway. PMID:19493577
Endocrine and metabolic responses of Anguilla anguilla L. caged in a freshwater-wetland (Pateira de Fermentelos--Portugal).
Teles, M; Pacheco, M; Santos, M A
The present short-term in situ study was carried out in a freshwater-wetland--Pateira de Fermentelos--considered an enlargement of Cértima River, in the centre of Portugal. This ecosystem is an important fishing and recreation place, receiving effluents from different origins namely, electroplating industrial effluents containing heavy metals, domestic wastes, as well as pesticides and fertilizers resulting from agriculture activities. The aim of the present research work was to monitor the effects induced by the contaminants present in Pateira de Fermentelos water, using Anguilla anguilla L. (European eel) as a bioindicator. The eels were caged for 48 h at four Pateira de Fermentelos sites, differing in their distances to the main known pollution source (Cértima River): A (close to the lagoon entrance), B, C and D (the farthest from the Cértima River). A reference site was selected near the Cértima river spring. The following parameters were measured: liver ethoxyresorufin-O-deethylase (EROD) and alanine transaminase (ALT) activities, plasma levels of cortisol, 17beta-estradiol (E2), thyroid-stimulating-hormone (TSH), free thyroxine (T4), free triiodothyronine (T3), as well as glucose and lactate. The erythrocytic nuclear abnormalities (ENA) frequency was also scored as a genotoxicity indicator. The results revealed increased plasma cortisol and glucose concentrations at all exposure sites, displaying a similar response pattern. Plasma T3 showed a significant decrease only at site A when compared to reference site, whereas plasma E2 increased at sites B and D when compared to all the other sites, including reference site. The present results indicate the Pateira de Fermentelos water contamination, demonstrating the usefulness of the adopted strategy. PMID:17150242
Organohalogen contaminants and reproductive hormones in incubating glaucous gulls (Larus hyperboreus) from the Norwegian Arctic.
Verreault, Jonathan; Letcher, Robert J; Ropstad, Erik; Dahl, Ellen; Gabrielsen, Geir W
Organohalogen contaminants detected globally in avian wildlife, including populations from the Arctic, have been related to various reproductive hormone potencies, and altered hormonal balance and functions. Besides legacy organochlorine (OC) substances, that is, polychlorinated biphenyls (PCBs) and OC pesticides and by-products, endocrine-disruptive properties have been defined for chemicals of new and emerging environmental concern, such as polybrominated diphenyl ethers (PBDEs) and metabolically derived products like methylsulfonyl (MeSO2)- and hydroxyl (OH)-PCBs. We investigated the relationships between plasma concentrations of selected legacy OCs, PBDEs, and MeSO2- and OH-PCB metabolites and the circulating reproductive hormones testosterone (T), 17beta-estradiol (E2), and progesterone (P4) in incubating male and female glaucous gulls (Larus hyperboreus) from the Norwegian Arctic. Principal component and regression analyses demonstrated that P4 levels in male glaucous gulls were associated positively with variations of sum (Y) PCB, dichloro-diphenyl-trichloroethane (sigmaDDT), chlordane (sigmaCHL), and sigmaPBDE concentrations, which were the most recalcitrant organohalogens determined in glaucous gulls. No such relationship was found for female glaucous gulls as well as between concentrations of any of the selected organohalogens and levels of T for both sexes. The E2 was not detected in any plasma samples. Present results were highly suggestive that exposure to high organohalogen concentrations in glaucous gulls, particularly the most persistent compound classes, may have the potential to interfere with steroidogenesis and impinge on circulating P4 homeostasis. Because significant effects were found in males exclusively, it cannot be completely ruled out that male glaucous gulls are more sensitive than females to organohalogen-mediated alteration of P4 synthesis and breakdown. PMID:17089723
Effect of menopause on the chemical control of breathing and its relationship with acid-base status.
Preston, Megan E; Jensen, Dennis; Janssen, Ian; Fisher, John T
This study examined the role of alterations in the chemoreflex control of breathing, acid-base balance, and their interaction in postmenopausal ventilatory adaptations. A modified iso-oxic hyperoxic and hypoxic CO(2)-rebreathing procedure was employed to evaluate central and peripheral chemoreflex drives to breathe, respectively, in 15 healthy postmenopausal and 20 premenopausal women of similar age. Arterialized venous blood samples were collected at rest for the estimation of arterial Pco(2) (Pa(CO(2))) and H(+) concentration ([H(+)]), plasma strong ion difference ([SID]) and total weak acid ([A](tot)) concentrations, and serum progesterone ([P(4)]) and 17beta-estradiol ([E(2)]) concentrations. In post- compared with premenopausal women, Pa(CO(2)), [SID], and the central chemoreflex ventilatory recruitment threshold for Pco(2) (VRTco(2)) were higher, whereas [P(4)] and [E(2)] were lower (all P < 0.05), with no significant change in central or peripheral chemoreflex sensitivity, peripheral chemoreflex VRTco(2), and [A](tot). The acidifying effect of an increased Pa(CO(2)) was offset by the alkalizing effect of an increased [SID], such that [H(+)] was preserved in post- compared with premenopausal women. Pa(CO(2)) correlated positively with the central chemoreflex VRTco(2) (r = 0.67, P < 0.01), which in turn correlated positively with [SID] (r = 0.53, P < 0.01) within the pooled data. In conclusion, the relative alveolar hypoventilation and attendant arterial hypercapnia in healthy post- compared with premenopausal women could be explained, in part, by the interaction of 1) reduced central, but not peripheral, chemoreflex VRTco(2), 2) increased [SID], and 3) reduced circulating female sex steroid hormone concentrations. PMID:19091912
Estrogenic activity of UV filter mixtures
Kunz, Petra Y. [University of Applied Sciences Northwestern Switzerland (FHNW), School of Life Sciences, Institute of Ecopreneurship, Gruendenstrasse 40, CH-4132 Muttenz (Switzerland) and University of Zuerich, Institute of Plant Biology, Limnology, CH-8802 Kilchberg (Switzerland)]. E-mail: firstname.lastname@example.com; Fent, Karl [University of Applied Sciences Northwestern Switzerland (FHNW), School of Life Sciences, Institute of Ecopreneurship, Gruendenstrasse 40, CH-4132 Muttenz (Switzerland) and Swiss Federal Institute of Technology (ETH), Department of Environmental Sciences, CH-8092 Zurich (Switzerland)]. E-mail: email@example.com
UV-absorbing chemicals (UV filters) are widely used for protection against UV radiation in sunscreens and in a variety of cosmetic products and materials. Depending on the breadth and factor of UV protection, they are added as single compounds or as a combination thereof. Some UV filters have estrogenic activity, but their activity and interactions in mixtures are largely unknown. In this work, we analyzed 8 commonly used UV filters, which are pure or partial hER{alpha} agonists, for their estrogenic activity in equieffective mixtures in a recombinant yeast assay carrying the human estrogen receptor alpha (hER{alpha}). Mixtures of two, four and eight UV filters alone, or in combination with 17 {beta} estradiol (E2), were assessed at different effect levels and no-observed-effect-concentrations (NOEC). Predictions of the joint effects of these mixtures were calculated by employing the concentration addition (Canada) and independent action (IA) model. Most binary mixtures comprising of pure hER{alpha} agonists showed a synergistic activity at all mixture combinations. Only in combination with benzophenone-1, antagonistic activity was observed at some effect levels. All mixtures of four or eight, pure or pure and partial hER{alpha} agonists, alone or including E2, showed synergistic activity at concentrations giving an increase of 10% of basal activity (BC10). This occurred even at concentrations that were at the NOEC level of each single compound. Hence, there were substantial mixture effects even though each UV filter was present at its NOEC level. These results show that significant interactions occur in UV filter mixtures, which is important for the hazard and risk assessments of these personal care products.
The link between the insecticide heptachlor epoxide, estradiol, and breast cancer.
Cassidy, Richard A; Natarajan, Sridhar; Vaughan, George M
Given the suspected effects of estrogens on breast cancer, xenoestrogenic insecticides may be a risk factor. Studies of the weak xenoestrogen, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), have failed to demonstrate a causal relationship, though another estrogenic organochlorine insecticide, dieldrin, belonging to the cyclodiene family, has recently been linked to breast cancer. Other cyclodienes such as heptachlor epoxide (HE) and oxychlordane (OC) present in breast tissue have not been evaluated as rigorously, presumably due to their lower concentration and lower recovery using solvent extraction procedures. We used sparging extraction coupled with gas chromatography to determine the levels of HE, OC, and DDE in adipose tissue within breast biopsies in a series of 34 women evaluated for breast abnormality. Of the three insecticides tested, only HE (p=0.007) was positively associated with prevalence of breast cancer in the biopsies. In rapid, non-genomic studies using isolated human leukocytes, flow cytometric methods were used to measure HE-induced oxidants and DNA damage. These studies indicated that HE, at concentrations similar to those in breast biopsies, induced an inverted-U increase in intracellular oxidants and DNA strand breaks [both blocked by specific nitric oxide- (NO-) synthesis blockade withL: -NMMA] in human polymorphonuclear leukocytes (PMNs). HE-treated PMNs also induced damage to surrounding lymphocytes in mixed-leukocyte incubations (also inhibited by NO blockade). The HE-induced changes in NO were inhibited by 17beta-estradiol-(17beta-E2) receptor antagonists and were mimicked by similar concentrations of 17beta-E2. The addition of tumor necrosis factor-alpha (TNF-alpha) increased intracellular oxidants and DNA damage and shifted the responses to lower HE concentrations. This study, along with others, suggests that HE-induced NO production may contribute to initiation, promotion, and progression of cancer. PMID:15770527
Effects of perfluorooctanesulfonate and perfluorobutanesulfonate on the growth and sexual development of Xenopus laevis.
Lou, Qin-Qin; Zhang, Yin-Feng; Zhou, Zhen; Shi, Ya-Li; Ge, Ya-Nan; Ren, Dong-Kai; Xu, Hai-Ming; Zhao, Ya-Xian; Wei, Wu-Ji; Qin, Zhan-Fen
Perfluorobutanesulfonate (PFBS), as a substitute for perfluorooctanesulfonate (PFOS), is widespread in the environment and biotic samples as well as PFOS. To investigate effects of PFOS and PFBS on the growth and sexual development of amphibians, we exposed Xenopus laevis tadpoles at a series of concentrations of PFOS and PFBS (0.1; 1; 100; 1,000 ?g/l) as well as 17-beta-estradiol (E2, 100 ng/l) and 5 alpha-androstan-17-beta-ol-3-one (DHT, 100 ng/l) from stage 46/47 to 2 months postmetamorphosis. We found that neither PFOS nor PFBS had a significant effect on the survival and growth. However, they caused hepatohistological impairment at higher concentrations (100; 1,000 ?g/l). Unlike E2, PFOS at all concentrations did not alter the sex ratio and induce intersex, but caused degeneration of spermatogonia in testes except for the lowest concentration. PFBS had no effect on the sex ratio and gonadal histology. PFOS and PFBS promoted expression of estrogen receptor (ER) and androgen receptor (AR), but not affected aromatase expression in the brain. The increase in expression of ER and AR suggests an increase in the responsiveness to the corresponding sex hormone and potential effects on sexual development. Our results show that PFBS as well as PFOS have adverse effects on hepato-histology and sexual development on X. laevis. Also, PFOS- and PFBS-induced increase in ER and AR expression highlights the need to further study effects of PFOS and PFBS on subsequently gonadal development, sexual dimorphism, and secondary sex characteristics in X. laevis. It is debatable that PFBS is widely used as a substitute of PFOS. PMID:23907449
Bodhankar, Sheetal; Offner, Halina
A major focus of our laboratory has been an in-depth evaluation as to how estrogens exert a pronounced protective effect on clinical and histological disease in the animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). An important issue regarding their therapeutic application has been the undesirable estrogenic side effects thought to be mediated primarily through 17?-estradiol (E2) binding to intracellular estrogen receptor alpha (ER?). With the discovery and characterization of GPR30 as the putative membrane estrogen receptor, we sought to study whether signaling through GPR30 was sufficient to mediate protection against EAE without engagement of ER?. Treatment of EAE in WT mice with G-1, a selective GPR30 agonist, retained estradiol's ability to protect against clinical and histological EAE without estrogenic side effects. G-1 treatment deviated cytokine profiles and enhanced suppressive activity of CD4+Foxp3+ Treg cells through a GPR30- and programmed death 1 (PD-1)-dependent mechanism. This novel finding was indicative of the protective effect of GPR30 activation in EAE and provides a strong foundation for the clinical application of GPR30 agonists such as G-1 in MS. However, future studies are needed to elucidate cross-signaling and evaluate possible additive effects of combined signaling through both GPR30 and ER-?. Deciphering the possible mechanism of involvement of GPR30 in estrogen-mediated protection against EAE may result in lowering treatment doses of E2 and GPR30 agonists that could minimize risks and maximize immunoregulation and therapeutic effects in MS. Alternatively, one might envision using E2 derivatives with reduced estrogenic activity alone or in combination with GPR30 agonists as therapies for both male and female MS patients. PMID:22247749
Eugenol triggers apoptosis in breast cancer cells through E2F1/survivin down-regulation
Background Breast cancer is a major health problem that threatens the lives of millions of women worldwide each year. Most of the chemotherapeutic agents that are currently used to treat this complex disease are highly toxic with long-term side effects. Therefore, novel generation of anti-cancer drugs with higher efficiency and specificity are urgently needed. Methods Breast cancer cell lines were treated with eugenol and cytotoxicity was measured using the WST-1 reagent, while propidium iodide/annexinV associated with flow cytometry was utilized in order to determine the induced cell death pathway. The effect of eugenol on apoptotic and pro-carcinogenic proteins, both in vitro and in tumor xenografts was assessed by immunoblotting. While RT-PCR was used to determine eugenol effect on the E2F1 and survivin mRNA levels. In addition, we tested the effect of eugenol on cell proliferation using the real-time cell electronic sensing system. Results Eugenol at low dose (2 ?M) has specific toxicity against different breast cancer cells. This killing effect was mediated mainly through inducing the internal apoptotic pathway and strong down-regulation of E2F1 and its downstream antiapoptosis target survivin, independently of the status of p53 and ER?. Eugenol inhibited also several other breast cancer related oncogenes, such as NF-?B and cyclin D1. Moreover, eugenol up-regulated the versatile cyclin-dependent kinase inhibitor p21WAF1 protein, and inhibited the proliferation of breast cancer cells in a p53-independent manner. Importantly, these anti-proliferative and pro-apoptotic effects were also observed in vivo in xenografted human breast tumors. Conclusion Eugenol exhibits anti-breast cancer properties both in vitro and in vivo, indicating that it could be used to consolidate the adjuvant treatment of breast cancer through targeting the E2F1/survivin pathway, especially for the less responsive triple-negative subtype of the disease. PMID:24330704
A study of autoionization phenomena in helium using (e, 2e) spectroscopy
NASA Astrophysics Data System (ADS)
Brunger, M. J.; Samardzic, O.; Kheifets, A. S.; Weigold, E.
Results are presented for the triple differential (e, 2e) cross sections in the region encompassing the helium n = 2 autoionization resonances at the respective incident energies 94.6, 96.6 and 99.6 eV. The scattered-electron angle in each case is 0953-4075/30/14/017/img1 and the range of ejected-electron angles are between 0953-4075/30/14/017/img2 and 0953-4075/30/14/017/img3. The measured coincidence ejected-electron spectra are analysed in terms of the Shore - Balashov parametrization to obtain the direct (e, 2e) cross section 0953-4075/30/14/017/img4 and the resonance parameters 0953-4075/30/14/017/img5 and 0953-4075/30/14/017/img6 for the 0953-4075/30/14/017/img7 and 0953-4075/30/14/017/img8 resonances as a function of ejected-electron momentum. These derived parameters are compared against the results of a calculation where configuration-interaction expansions for the resonances and helium ground state, which employed hydrogenic and multiconfiguration Hartree - Fock orbitals, respectively, were used. Here the distorted-wave Born approximation was employed for the (e, 2e) cross section calculation. The calculated parameters agree quite well with the experimental results indicating that the theoretical description of the reaction mechanism is physically realistic. Further, both experiment and theory show strong correlations between the resonance amplitudes and the direct ionization amplitudes. Finally, we report and discuss our results of an experimental investigation into the post-collision interaction effects for the present kinematical conditions.
Secondary-electron emission mechanism of LiF film by (e,2e) spectroscopy
NASA Astrophysics Data System (ADS)
Samarin, S.; Berakdar, J.; Suvorova, A.; Artamonov, O. M.; Waterhouse, D. K.; Kirschner, J.; Williams, J. F.
Secondary-electron emission (SEE) from LiF films deposited on Si(0 0 1) surface was studied using time-of-flight two-electron coincidence spectroscopy. A set of energy-distribution curves (EDCs) of secondary electrons excited from a LiF film by electrons with energies in the range of 20-50 eV exhibits emission features at about 7 and 11 eV. The energy positions of these maxima do not depend on the incident energy. To reveal the origin of these features, each of the EDCs was spanned in the second dimension E2 using two-electron coincidence spectroscopy. Two-dimensional mapping of the energy sharing between correlated electrons shows that above 25 eV incident energy, one electron of the pair is preferentially emitted with E1=7.2±0.3 eV energy and the second one with energy E2=( Ep-23.3)±0.5 eV, where Ep is the incident electron energy. At about 30 eV incident energy, a second favoured emission energy of 10.9 ± 0.3 eV is observed. The unique capability of (e,2e) spectroscopy established the links between electron energy loss process and emission features in the EDCs. It is suggested that the mechanism of SEE from LiF film includes the excitation of two collective excitations with subsequent decay via electron ejection. It was shown that the mechanism of secondary emission from LiF film depends on the film thickness and its structure.
[Induced abortion using prostaglandin E2 and F2alpha gel].
Lippert, T H; Modly, T
In this study of 20 patients in the 13th-17th week of pregnancy abortion was induced with intrauterine, extraamniotic application of prostaglandins (PG) E2 or F2 in gel form. The gel composition was as follows: 4% tylose MH 300, 2% glycerine, 1% chlorhexidine digluconate, 83% sterile distilled water and 10% PG stock solution. Both PGE2 and PGF2 gels were used. Final concentration was 2.5 mg E2 or 2.5 mg F2 per g of gel. Gel was applied via transcervical, extraamniotic polyethylene catheter every 2-3 hours. Results: PGE2-gel was used in 14 cases. After 3-4 applications both fetus and placenta were expelled. Average dose used was 4.6 mg E2/patient. First contractions started in 30 minutes; induction to expulsion time was 11 hours 35 minutes. F2-gel given to 6 patients resulted in expulsion of the fetus in all cases but placenta needed removal by curettage in 4 patients. Average dose per patient was 17.7 mg of F2; first contractions in 30 minutes, average expulsion time 17 hours 38 minutes. With both PGs there were painful contractions which were controlled with a combination of pentazocine and Valium. PGE2 caused vomiting in 5 patients. No increased bleeding or postabortion infection occurred. Follow-up curettage was done in all patients to ensure removal of all tissues. Overall evaluation of the PG-gels was considered good. PG stability in gel form is good; during 8 months of preservation in sterile aluminum tubes at -25 degrees Celsius no decline in clinical effectiveness was noted. The gel application is less expensive than the slow-injection pump method. PMID:4473406
Development of an (e,2e) electron momentum spectroscopy apparatus using an ultrashort pulsed electron gun
Yamazaki, M.; Kasai, Y.; Oishi, K.; Nakazawa, H.; Takahashi, M. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan)
An (e,2e) apparatus for electron momentum spectroscopy (EMS) has been developed, which employs an ultrashort-pulsed incident electron beam with a repetition rate of 5 kHz and a pulse duration in the order of a picosecond. Its instrumental design and technical details are reported, involving demonstration of a new method for finding time-zero. Furthermore, EMS data for the neutral Ne atom in the ground state measured by using the pulsed electron beam are presented to illustrate the potential abilities of the apparatus for ultrafast molecular dynamics, such as by combining EMS with the pump-and-probe technique.
Isoscalar E0, E1, and E2 strength in Ca-40
Youngblood, David H.; Lui, YW; Clark, HL.
in the scattering plane. The out- of-plane scattering angle was not measured. Position resolu- tion of approximately 0.9 mm and scattering angle resolution 0556-2813/2001/63~6!/067301~4!/$20.00 63 067301- E2 strength in 40Ca . Lui, and H. L. Clark , College... to their calculation in Fig. 4. The agreement is quite remark- able. This work was supported in part by the U.S. Department of Energy under Grant No. DE-FG03-93ER40773 and by The Robert A. Welch Foundation. @1# D. H. Youngblood, Y.-W. Lui, and H. L. Clark, Phys...
(e,2e) and (Î3,2e) Processes: Open and Closed Questions
NASA Astrophysics Data System (ADS)
An important breakthrough has been achieved recently in the description of (e,2e) and (Î3,2e) processes with the development of new ab-initio theories: the external complex scaling theory (ECS), the time dependent close coupling theory (TDCC), and the hyperspherical R-matrix theory with semiclassical outgoing waves (HRM-SOW). The principles of these various theories are summarized, their relations are considered, and their achievements are discussed with respect to the available experimental data regarding electron impact ionization of H and photo double ionization of He. Possible directions for future work are outlined.
Indole and (E)-2-hexenal, phytochemical potentiators of polymyxins against Pseudomonas aeruginosa and Escherichia coli.
Kubo, A; Lunde, C S; Kubo, I
Combinations of polymyxins and phytochemicals were tested for antimicrobial activity against two gram-negative bacteria. Various degrees of potentiation were found against Pseudomonas aeruginosa and Escherichia coli with (E)-2-hexenal and indole. Three-compound combinations were found to further increase the activity of polymyxin B sulfate and colistin methanesulfonate against both bacteria. Combinations with colistin against P. aeruginosa resulted in the highest degree of potentiation, with a 512-fold increase in colistin antimicrobial activity. These results indicate the potential efficacy of phytochemical combinations with antibiotics to enhance total biological activity. PMID:8726016
Future climate change under RCP emission scenarios with GISS ModelE2
Nazarenko, L.; Schmidt, G. A.; Miller, R. L.; Tausnev, N.; Kelley, M.; Ruedy, R.; Russell, G. L.; Aleinov, I.; Bauer, M.; Bauer, S.; et al
We examine the anthropogenically forced climate response for the 21st century representative concentration pathway (RCP) emission scenarios and their extensions for the period 2101–2500. The experiments were performed with ModelE2, a new version of the NASA Goddard Institute for Space Sciences (GISS) coupled general circulation model that includes three different versions for the atmospheric composition components: a noninteractive version (NINT) with prescribed composition and a tuned aerosol indirect effect (AIE), the TCAD version with fully interactive aerosols, whole-atmosphere chemistry, and the tuned AIE, and the TCADI version which further includes a parameterized first indirect aerosol effect on clouds. Each atmosphericmore »version is coupled to two different ocean general circulation models: the Russell ocean model (GISS-E2-R) and HYCOM (GISS-E2-H). By 2100, global mean warming in the RCP scenarios ranges from 1.0 to 4.5°#2;C relative to 1850–1860 mean temperature in the historical simulations. In the RCP2.6 scenario, the surface warming in all simulations stays below a 2#2;°C threshold at the end of the 21st century. For RCP8.5, the range is 3.5–4.5°#2;C at 2100. Decadally averaged sea ice area changes are highly correlated to global mean surface air temperature anomalies and show steep declines in both hemispheres, with a larger sensitivity during winter months. By the year 2500, there are complete recoveries of the globally averaged surface air temperature for all versions of the GISS climate model in the low-forcing scenario RCP2.6. TCADI simulations show enhanced warming due to greater sensitivity to CO?, aerosol effects, and greater methane feedbacks, and recovery is much slower in RCP2.6 than with the NINT and TCAD versions. All coupled models have decreases in the Atlantic overturning stream function by 2100. In RCP2.6, there is a complete recovery of the Atlantic overturning stream function by the year 2500 while with scenario RCP8.5, the E2-R climate model produces a complete shutdown of deep water formation in the North Atlantic.« less
On-orbit calibration of soft X-ray detector on Chang'E-2 satellite
Xiao, Hong; Wang, Huanyu; Cui, Xingzhu; Guo, Dongya
X-ray spectrometer is one of the satellite payloads on Chang'E-2 satellite. The soft X-ray detector is one of the device on X-ray spectrometer which is designed to detect the major rock-forming elements within 0.5-10keV range on lunar surface. In this paper, energy linearity and energy resolution calibration is done using a weak Fe55 source, while temperature and time effect is considered not take big error. The total uncertainty is estimated to be within 5% after correction.
On-orbit calibration of soft X-ray detector on Chang'E-2 satellite
Hong Xiao; Wenxi Penga; Huanyu Wang; Xingzhu Cui; Dongya Guo
X-ray spectrometer is one of the satellite payloads on Chang'E-2 satellite. The soft X-ray detector is one of the device on X-ray spectrometer which is designed to detect the major rock-forming elements within 0.5-10keV range on lunar surface. In this paper, energy linearity and energy resolution calibration is done using a weak Fe55 source, while temperature and time effect is considered not take big error. The total uncertainty is estimated to be within 5% after correction.
Berberine, an isoquinoline alkaloid, inhibits melanoma cancer cell migration by reducing the expressions of cyclooxygenase-2, prostaglandin E2 and prostaglandin E2 receptors
Singh, Tripti; Vaid, Mudit; Katiyar, Nandan; Sharma, Samriti; Katiyar, Santosh K.
Melanoma is the leading cause of death from skin disease due, in large part, to its propensity to metastasize. We have examined the effect of berberine, an isoquinoline alkaloid, on human melanoma cancer cell migration and the molecular mechanisms underlying these effects using melanoma cell lines, A375 and Hs294. Using an in vitro cell migration assay, we show that over expression of cyclooxygenase (COX)-2, its metabolite prostaglandin E2 (PGE2) and PGE2 receptors promote the migration of cells. We found that treatment of A375 and Hs294 cells with berberine resulted in concentration-dependent inhibition of migration of these cells, which was associated with a reduction in the levels of COX-2, PGE2 and PGE2 receptors (EP2 and EP4). Treatment of cells with celecoxib, a COX-2 inhibitor, or transient transfection of cells with COX-2 small interfering RNA, also inhibited cell migration. Treatment of the cells with 12-O-tetradecanoylphorbol-13-acetate (TPA), an inducer of COX-2 or PGE2, enhanced cell migration, whereas berberine inhibited TPA- or PGE2-promoted cell migration. Berberine reduced the basal levels as well as PGE2-stimulated expression levels of EP2 and EP4. Treatment of the cells with the EP4 agonist stimulated cell migration and berberine blocked EP4 agonist-induced cell migration activity. Moreover, berberine inhibited the activation of nuclear factor-kappa B (NF-?B), an upstream regulator of COX-2, in A375 cells, and treatment of cells with caffeic acid phenethyl ester, an inhibitor of NF-?B, inhibited cell migration. Together, these results indicate for the first time that berberine inhibits melanoma cell migration, an essential step in invasion and metastasis, by inhibition of COX-2, PGE2 and PGE2 receptors. PMID:20974686
Hyperforin, an Anti-Inflammatory Constituent from St. John's Wort, Inhibits Microsomal Prostaglandin E(2) Synthase-1 and Suppresses Prostaglandin E(2) Formation in vivo.
Koeberle, Andreas; Rossi, Antonietta; Bauer, Julia; Dehm, Friederike; Verotta, Luisella; Northoff, Hinnak; Sautebin, Lidia; Werz, Oliver
The acylphloroglucinol hyperforin (Hyp) from St. John's wort possesses anti-inflammatory and anti-carcinogenic properties which were ascribed among others to the inhibition of 5-lipoxygenase. Here, we investigated whether Hyp also interferes with prostanoid generation in biological systems, particularly with key enzymes participating in prostaglandin (PG)E(2) biosynthesis, i.e., cyclooxygenases (COX)-1/2 and microsomal PGE(2) synthase (mPGES)-1 which play key roles in inflammation and tumorigenesis. Similar to the mPGES-1 inhibitors MK-886 and MD-52, Hyp significantly suppressed PGE(2) formation in whole blood assays starting at 0.03-1 ?M, whereas the concomitant generation of COX-derived 12(S)-hydroxy-5-cis-8,10-trans-heptadecatrienoic acid, thromboxane B(2), and 6-keto PGF(1?) was not significantly suppressed up to 30 ?M. In cell-free assays, Hyp efficiently blocked the conversion of PGH(2) to PGE(2) mediated by mPGES-1 (IC(50)?=?1 ?M), and isolated COX enzymes were not (COX-2) or hardly (COX-1) suppressed. Intraperitoneal (i.p.) administration of Hyp (4?mg kg(-1)) to rats impaired exudate volume and leukocyte numbers in carrageenan-induced pleurisy associated with reduced PGE(2) levels, and Hyp (given i.p.) inhibited carrageenan-induced mouse paw edema formation (ED(50)?=?1?mg kg(-1)) being superior over indomethacin (ED(50)?=?5?mg kg(-1)). We conclude that the suppression of PGE(2) biosynthesis in vitro and in vivo by acting on mPGES-1 critically contributes to the anti-inflammatory efficiency of Hyp. PMID:21687502
Characterization and Epitope Mapping of Human Monoclonal Antibodies to PDC-E2, the Immunodominant Autoantigen of Primary Biliary Cirrhosis
Leung, Patrick S. C.; Krams, Sheri; Munoz, Santiago; Surh, Charles P.; Ansari, Aftab; Kenny, Thomas; Robbins, Dick L.; Fung, John; Starzl, Thomas E.; Maddrey, Willis; Coppel, Ross L.; Gershwin, M. Eric
Further to define the epitopes of PDC-E2, the major autoantigen in primary biliary cirrhosis (PBC), we have developed and characterized five human monoclonal antibodies. These antibodies were derived by fusing a regional hepatic lymph node from a patient with PBC with the mouse human heterohybrid cell line F3B6. Previous studies of epitope mapping ofPDC-E2 have relied on whole sera and have suggested that the immunodominant epitope lies within the inner lipoyl domain of the molecule. However, selective absorption studies using whole sera and a series of overlapping recombinant peptides of PDC-E2 have suggested that the epitope may also include a large conformational component. Moreover, several laboratories have suggested that autoantibodies against the 2-oxo acids dehydrogenase autoantigens are cross-reactive. The five Inonoclonal antibodies generated included three IgG2a and two IgM antibodies and were studied for antigen specificity using recombinant PDC-E2, recombinant BCKD-E2, histone, dsDNA, IgG (Fe), collagen and a recombinant irrelevant liver specific control, the F alloantigen. The antibodies were also used to probe blots of human, bovine, mouse and rat mitochondria. Finally, fine specificity was studied by selective ELISA and absorption against overlapping expressing fragments of PDC-E2. All five monoclonals, but none of the other mitochondrial auto antigens were specific for PDC-E2. In fact, although affinity purified antibodies to PDC-E2 from patients with PBC cross-reacted with protein X, the human monoclonals did not, suggesting that protein X contains an epitope distinct from that found on PDC-E2. Additionally, all three IgG2 monoclonals recognized distinct epitopes within the inner lipoyl domain of PDC-E2. PMID:1283300
Characterization of species-specific genes regulated by E2-2 in human plasmacytoid dendritic cells
Cheng, Menglan; Zhang, Xuyuan; Yu, Haisheng; Du, Peishuang; Plumas, Joël; Chaperot, Laurance; Su, Lishan; Zhang, Liguo
Dendritic cells (DCs) are sentinels of the immune system and comprise two distinct subsets: conventional DCs (cDCs) and plasmacytoid DCs (pDCs). Human pDCs are distinguished from mouse pDCs phenotypically and functionally. Basic helix-loop-helix protein E2-2 is defined as an essential transcription factor for mouse pDC development, cell fate maintenance and gene programe. It is unknown whether E2-2 regulation contributes to this species-specific difference. Here we investigated the function of E2-2 in human pDCs and screened human-specific genes regulated by E2-2. Reduced E2-2 expression in human pDC cell line GEN2.2 resulted in diminished IFN-? production in response to CpG but elevated antigen presentation capacity. Gene expression profiling showed that E2-2 silence down-regulated pDC signature genes but up-regulated cDC signature genes. Thirty human-specific genes regulated by E2-2 knockdown were identified. Among these genes, we confirmed that expression of Siglec-6 was inhibited by E2-2. Further more, Siglec-6 was expressed at a higher level on a human pDC subset with drastically lower expression of E2-2. Collectively, these results highlight that E2-2 modulates pDC function in a species-specific manner, which may provide insights for pDC development and functions. PMID:26182859
A naturally occurring substitution in the E2 protein of Salmonid alphavirus subtype 3 changes viral fitness.
Karlsen, Marius; Andersen, Linda; Blindheim, Steffen H; Rimstad, Espen; Nylund, Are
Phylogenetic analyses of the Salmonid alphavirus subtype 3 (SAV3) epizootic have suggested that a substitution from proline to serine in the receptor binding protein E2 position 206 has occurred after the introduction of virus from a wild reservoir to farmed salmonid fish in Norway. We modelled the 3D structure of P62, the uncleaved E3-E2 precursor, of SAVH20/03 based on its sequence homology to the Chikungunya virus (CHIKV), and studied in vitro and in vivo effects of the mutation using reverse genetics. E2(206) is located on the surface of the B-domain of E2, which is associated with receptor attachment in alphaviruses. Recombinant virus expressing the E2(206S) codon replicated slower and produced significantly less genomic copies than virus expressing the ancestral E2(206P) codon in vitro in Bluegill Fry (BF2) cells. The E2(206S) mutant was out-competed by the E2(206P) mutant after 5 passages in an in vitro competition assay, confirming that the substitution negatively affects the efficacy of virus multiplication in cell culture. Both mutants were highly infectious to Atlantic salmon (Salmo salar), produced similar viral RNA loads in gills, heart, kidney and brain, and induced similar histopathologic changes in these organs. The E2(206S) mutant produced a less persistent infection in salmon and was shed more rapidly to water than the E2(206P) mutant. Reduced generation time through more rapid shedding could therefore explain why a serine in this position became dominant in the viral population after SAV3 was introduced to farmed salmon from the wild reservoir. PMID:25445347
E2F transcription factor 1 regulates cellular and organismal senescence by inhibiting Forkhead box O transcription factors.
Xie, Qi; Peng, Shengyi; Tao, Li; Ruan, Haihe; Yang, Yanglu; Li, Tie-Mei; Adams, Ursula; Meng, Songshu; Bi, Xiaolin; Dong, Meng-Qiu; Yuan, Zengqiang
E2F1 and FOXO3 are two transcription factors that have been shown to participate in cellular senescence. Previous report reveals that E2F1 enhanced cellular senescence in human fibroblast cells, while FOXO transcription factors play against senescence by regulation reactive oxygen species scavenging proteins. However, their functional interplay has been unclear. Here we use E2F1 knock-out murine Embryonic fibroblasts (MEFs), knockdown RNAi constructs, and ectopic expression of E2F1 to show that it functions by negatively regulating FOXO3. E2F1 attenuates FOXO3-mediated expression of MnSOD and Catalase without affecting FOXO3 protein stability, subcellular localization, or phosphorylation by Akt. We mapped the interaction between E2F1 and FOXO3 to a region including the DNA binding domain of E2F1 and the C-terminal transcription-activation domain of FOXO3. We propose that E2F1 inhibits FOXO3-dependent transcription by directly binding FOXO3 in the nucleus and preventing activation of its target genes. Moreover, knockdown of the Caenorhabditis elegans E2F1 ortholog efl-1 significantly extends lifespan in a manner that requires the activity of the C. elegans FOXO gene daf-16. We conclude that there is an evolutionarily conserved signaling connection between E2F1 and FOXO3, which regulates cellular senescence and aging by regulating the activity of FOXO3. We speculate that drugs and/or therapies that inhibit this physical interaction might be good candidates for reducing cellular senescence and increasing longevity. PMID:25344604
Antifibrotic Effects of Noscapine through Activation of Prostaglandin E2 Receptors and Protein Kinase A*
Kach, Jacob; Sandbo, Nathan; La, Jennifer; Denner, Darcy; Reed, Eleanor B.; Akimova, Olga; Koltsova, Svetlana; Orlov, Sergei N.; Dulin, Nickolai O.
Myofibroblast differentiation is a key process in the pathogenesis of fibrotic disease. We have shown previously that differentiation of myofibroblasts is regulated by microtubule polymerization state. In this work, we examined the potential antifibrotic effects of the antitussive drug, noscapine, recently found to bind microtubules and affect microtubule dynamics. Noscapine inhibited TGF-?-induced differentiation of cultured human lung fibroblasts (HLFs). Therapeutic noscapine treatment resulted in a significant attenuation of pulmonary fibrosis in the bleomycin model of the disease. Noscapine did not affect gross microtubule content in HLFs, but inhibited TGF-?-induced stress fiber formation and activation of serum response factor without affecting Smad signaling. Furthermore, noscapine stimulated a rapid and profound activation of protein kinase A (PKA), which mediated the antifibrotic effect of noscapine in HLFs, as assessed with the PKA inhibitor, PKI. In contrast, noscapine did not activate PKA in human bronchial or alveolar epithelial cells. Finally, activation of PKA and the antifibrotic effect of noscapine in HLFs were blocked by the EP2 prostaglandin E2 receptor antagonist, PF-04418948, but not by the antagonists of EP4, prostaglandin D2, or prostacyclin receptors. Together, we demonstrate for the first time the antifibrotic effect of noscapine in vitro and in vivo, and we describe a novel mechanism of noscapine action through EP2 prostaglandin E2 receptor-mediated activation of PKA in pulmonary fibroblasts. PMID:24492608
Parametrizations of triaxial deformation and E2 transitions of the wobbling band
Shimizu, Yoshifumi R.; Shoji, Takuya [Department of Physics, Graduate School of Sciences, Kyushu University, Fukuoka 812-8581 (Japan); Matsuzaki, Masayuki [Department of Physics, Fukuoka University of Education, Munakata, Fukuoka 811-4192 (Japan)
There are various different definitions for the triaxial deformation parameter '{gamma}'. It is pointed out that the parameter conventionally used in the Nilsson (or Woods-Saxon) potential, {gamma}(pot:Nils) [or {gamma}(pot:WS)], is not appropriate for representing the triaxiality {gamma} defined in terms of the intrinsic quadrupole moments. The difference between the two can be as large as a factor two in the case of the triaxial superdeformed bands recently observed in Hf and Lu nuclei, i.e., {gamma}(pot:Nils){approx_equal}20 deg. corresponds to {gamma}{approx_equal}10 deg. In our previous work, we studied the wobbling excitations in Lu nuclei using the microscopic framework of the cranked Nilsson mean-field and the random phase approximation. The most serious problem was that the calculated B(E2) value is about factor two too small. It is shown that the origin of this underestimate can mainly be attributed to the small triaxial deformation parameter {gamma}{approx_equal}10 deg. that corresponds to {gamma}(pot:Nils){approx_equal}20 deg. If the same triaxial deformation parameter is used as in the analysis of the particle-rotor model, {gamma}{approx_equal}20 deg., the calculated B(E2) gives correct magnitude of the experimental data.
Association of the Apolipoprotein E 2 Allele with Concurrent Occurrence of Endometrial Hyperplasia and Endometrial Carcinoma
Ivanova, Tatiana I.; Krikunova, Ludmila I.; Ryabchenko, Nikolay I.; Mkrtchyan, Liana S.; Khorokhorina, Vera A.; Salnikova, Lyubov E.
Genes encoding proteins with antioxidant properties may influence susceptibility to endometrial hyperplasia (EH) and endometrial carcinoma (ECa). Patients with EH (n = 89), EH concurrent with ECa (n = 76), ECa (n = 186), and healthy controls (n = 1110) were genotyped for five polymorphic variants in the genes involved in metabolism of lipoproteins (APOE Cys112Arg and Arg158Cys), iron (HFE Cys282Tyr and His63Asp), and catecholamines (COMT Val158Met). Patients and controls were matched by ethnicity (all Caucasians), age, body mass index (BMI), and incidence of hypertension and diabetes. The frequency of the APOE E 2 allele (158Cys) was higher in patients with EH + ECa than in controls (P = 0.0012, PBonferroni = 0.018, OR = 2.58, 95% CI 1.49–4.45). The APOE E 4 allele (112Arg) was more frequently found in patients with EH than in controls and HFE minor allele G (63Asp) had a protective effect in the ECa group, though these results appeared to be nonsignificant after correction for multiple comparisons. The results of the study indicate that E 2 allele might be associated with concurrent occurrence of EH and ECa. PMID:25741405
Interferon-Inducible Ubiquitin E2, Ubc8, Is a Conjugating Enzyme for Protein ISGylation†
Kim, Keun Il; Giannakopoulos, Nadia V.; Virgin, Herbert W.; Zhang, Dong-Er
Protein ISGylation is unique among ubiquitin-like conjugation systems in that the expression and conjugation processes are induced by specific stimuli, mainly via the alpha/beta interferon signaling pathway. It has been suggested that protein ISGylation plays a special role in the immune response, because of its interferon-signal dependency and its appearance only in higher eukaryotic organisms. Here, we report the identification of an ISG15-conjugating enzyme, Ubc8. Like other components of the protein ISGylation system (ISG15, UBE1L, and UBP43), Ubc8 is an interferon-inducible protein. Ubc8 clearly mediates protein ISGylation in transfection assays. The reduction of Ubc8 expression by small interfering RNA causes a decrease in protein ISGylation in HeLa cells upon interferon treatment. Neither UbcH7/UbcM4, the closest homologue of Ubc8 among known ubiquitin E2s, nor the small ubiquitin-like modifier E2 Ubc9 supports protein ISGylation. These findings strongly suggest that Ubc8 is a major ISG15-conjugating enzyme responsible for protein ISGylation upon interferon stimulation. Furthermore, we established an assay system to detect ISGylated target proteins by cotransfection of ISG15, UBE1L, and Ubc8 together with a target protein to be analyzed. This method provides an easy and effective way to identify new targets for the ISGylation system and will facilitate related studies. PMID:15485925
New insights of asteroid 4179 Toutatis using China Chang'e-2 close flyby optical measurements
Bu, Yanlong; Tang, Geshi; Cao, Jianfeng; Hu, Songjie; Yang, Cheng; Liu, Chuankai [Aerospace Flight Dynamics Laboratory, Beijing Aerospace Control Center, PO Box 5130, Beijing 100094 (China); Di, KaiChang; Xu, Bin; Liu, Bin [Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100101 (China); Fa, Wenzhe [School of Earth and Space Sciences, Peking University, Peking 100871 (China); Hu, Tianjiang [College of Mechatronics and Automation, National University of Defense Technology, 410073 (China); Ding, Chibiao, E-mail: email@example.com, E-mail: email@example.com [Institute of Electronics, Chinese Academy of Sciences, 100190 (China)
The mysteries of near-Earth asteroid 4179 Toutatis have been more comprehensively unveiled by analyzing the optical images taken during the Chang'e-2 flyby in 2012. Compared with previous works, this paper concentrates on the photogrammetric relation between the Chang'e-2 spacecraft and Toutatis and the imaging shadow effect during the flyby. Accurate models of imaging and optical measurements are developed to study Toutatis's dimensions and rotational state at the time of imaging. As the illumination study shows, the shadowed region perpendicular to the long axis accounts for 27.78% of the Toutatis images, while the long axis of the body is fully captured. With a compensation on the shadow effect, the optical measurements reveal that Toutatis's long axis is 4354 ± 56 m, the maximum length is 4391 ± 56 m, and the spatial orientation described with the angles of direction cosine during the flyby is (126.°13 ± 0.°29, 122.°98 ± 0.°21, 126.°63 ± 0.°46). Furthermore, a new triaxial ellipsoid of 4354 × 1835 × 2216 m and a volume of 7.5158 km{sup 3} are proposed based on the previous Toutatis shape model. The effectiveness of the proposed method is validated, since typical features such as the neck and endpoints agree well with the results simultaneously observed by the ground radar. Moreover, it also potentially provides a feasible approach to precisely calculate the spin period of Toutatis.
The identification of prostaglandins E2, F2? and A2 from rabbit kidney medulla
Lee, J. B.; Crowshaw, K.; Takman, B. H.; Attrep, Katherine A.; Gougoutas, J. Z.
Rabbit kidney medulla (10kg.) was homogenized in 5mm-disodium hydrogen phosphate and deproteinized with ethanol, and the concentrated supernatant solution was extracted at pH8 with light petroleum and at pH2 with chloroform. The acidic lipids present in the chloroform phase were separated on silicic acid columns into three biologically active fractions. The first fraction contained only vasodepressor activity; the second fraction contained both vasodepressor and non-vascular-smooth-muscle-stimulating activity; the third fraction contained both vasopressor and non-vascular-smooth-muscle-stimulating activity. Purification of each fraction by reversed-phase partition and thick-layer chromatography yielded three pure acids. Thin-layer chromatographic, spectroscopic and mass-spectral analysis of the acids and their methyl esters established their structures as prostaglandins E2, F2? and A2. Evidence is presented demonstrating that part or all of the prostaglandin A2 is formed during the isolation procedures from endogenous prostaglandin E2. PMID:16742553
Pure E2 transitions: A test for BRICC Internal Conversion Coefficients
Gerl, J. [Gesellschaft fur Schwerionenforschung, GSI, 64291 Darmstadt (Germany); Sai, K. Vijay; Sainath, M.; Gowrishankar, R.; Venkataramaniah, K. [Department of Physics, Sri Sathya Sai University, Prasanthinilayam 515134, AP (India)
The most widely used theoretical internal conversion coefficient (ICC) tables are of Hager and Seltzer (HS), Rosel et al. and BRICC (Band et al. tables using BRICC interpolation code). A rigorous comparison of experimental ICCs with various theoretical tabulations is possible only when a large data on experimental ICCs is available at one place. For this reason, a compilation of all the available experimental ICCs, {alpha}{sub T}, {alpha}{sub K}, {alpha}{sub L} of E2 transitions for a number of elements in the range of 24{<=}Z{<=}94 is presented. Listing of experimental data includes 595 datasets corresponding to 505 E2 transitions in 165 nuclei across the nuclear chart. Data with less than 10% experimental uncertainty have been selected for comparison with the theoretical values of Hager and Seltzer, Rosel et al. and BRICC. The relative percentage deviation (%{delta}) have been calculated for each of the above theories and the average (%{delta}) are estimated. The Band et al. tables, using the BRICC interpolation code are seen to give theoretical ICCs closest to experimental values.
Detection of ethylene glycol - toward W51/e2 and G34.3+0.02
NASA Astrophysics Data System (ADS)
Lykke, Julie M.; Favre, Cécile
Ethylene glycol (HOCH2CH2OH), also commenly known as antifreeze, is the reduced alcohol version of glycolaldehyde (CH2OHCHO). Glycoladehyde - the simplest possible aldehyde sugar (Marstokk and Mřllendal 1973) - is the first intermediate step in the path toward forming more complex and biologically relevant molecules through the the formose reaction, which begins with formaldehyde (H2CO) and ends with the formation of sugars and ultimately ribose, the backbone of RNA (e.g., Larralde et al. 1995). The presence of glycolaldehyde is therefore an important indication that processes leading to biologically relevant molecules are taking place. It is however, still unclear as to how glycolaldehyde and ethylene glycol are formed in the ISM. It has been proposed that they share a common formation pathway through UV-irradiation of methanol (CH3OH) ices mixed with CO (Öberg et al. 2009). So far, ethylene glycol, in its lower energy con-former (g'Ga(CH2OH)2), has been detected toward SgrB2 (N) by Hollis et al. (2002), tentatively toward IRAS 16293-2422 (Jřrgensen et al. 2012) and marginally by Kalenskii and Johansson (2010) toward W51 e1/e2. Here we present a firm detection of ethylene glycol toward W51/e2 as well as a first detection toward G34.3+0.02 at 1mm and 3mm using the IRAM 30m telescope.
Plasma levels, metabolic clearance rates, and rates of secretion of testosterone and estradiol-l7 beta in the silver eel (Anguilla anguilla L. )
Querat, B.; Hardy, A.; Leloup-Hatey, J.
Testosterone (T) and 17 beta-estradiol (E2) plasma levels and metabolic clearance rates (MCR) were measured to investigate their ovarian production in immature silver eel. The dynamics of T and E2 metabolism were studied in catheterized eels using single injections of 0.2 to 0.5 microCi /sup 3/H-labeled steroid. The distribution volumes, biological half-life and MCR of nonconjugated tracers were calculated on the basis of a two-compartment model. At the end of the experiments, radioactivity was measured in different organs and tissues to localize the site of T and E2 catabolism. The volume of the inner compartment was 3.4% for T and E2. The outer compartment was larger for T (6.4%) than that for E2 (4.3%). The biological half-life was three to four times shorter for T (14.5 hr) than that for E2 (48.5 hr). The MCR for T (1.71 ml/kg body wt/hr) was higher than for E2 (0.51 ml/kg body wt/hr). Plasma levels were determined, using radioimmunoassay, on samples taken before injections of radiolabeled steroid. Free or protein-bound hormone levels were 0.12 and 0.31 ng/ml for T and E2, respectively. Conjugated T and E2 levels were, respectively, 0.13 and 0.23 ng/ml. Production rates were determined as the product of the MCR and the plasma concentration of the nonconjugated hormone. No significant differences were observed between the production rates of T and E2 (0.24 ng/kg body wt/hr). The liver was the principal site of metabolism for both hormones, which were excreted via the enterohepatic route. E2 injection gave rise to no metabolite in the plasma whereas after T injection a metabolite was produced, the concentration of which increased as a function of time. Its chromatographic properties were different from that of E2 or androstenedione, suggesting that no significant peripheral aromatization or 17-oxidoreduction occurs in the immature silver eel.
RING E3-Catalyzed E2 Self-Ubiquitination Attenuates the Activity of Ube2E Ubiquitin-Conjugating Enzymes.
Banka, Prerana Agarwal; Behera, Adaitya Prasad; Sarkar, Sayani; Datta, Ajit B
Ubiquitination of a target protein is accomplished through sequential actions of the E1, E2s, and the E3s. E2s dictate the modification topology while E3 ligases confer substrate specificity and recruit the cognate E2. Human genome codes for ~35 different E2 proteins; all of which contain the characteristic ubiquitin-conjugating UBC core domain sufficient for catalysis. Many of these E2 enzymes also have N- or C-terminal extensions; roles of which are not very well understood. We show that the N-terminal extension of Ube2E1 undergoes intramolecular auto-ubiquitination. This self-ubiquitination activity is enhanced in the presence of interacting RING E3 ligases and results in a progressive attenuation of the E2 activity toward substrate/E3 modification. We also find that the N-terminal ubiquitination sites are conserved in all the three Ube2Es and replacing them with arginine renders all three full-length Ube2Es equally active as their core UBC domains. Based on these results, we propose that E3-catalyzed self-ubiquitination acts as a key regulatory mechanism that controls the activity of Ube2E class of ubiquitin E2s. PMID:25960396
E2F-Dependent Histone Acetylation and Recruitment of the Tip60 Acetyltransferase Complex to Chromatin in Late G1
Stefan Taubert; Chiara Gorrini; Scott R. Frank; Tiziana Parisi; Miriam Fuchs; Ho-Man Chan; David M. Livingston; Bruno Amati
E2F proteins can either activate or repress transcription. Following mitogenic stimulation, repressive E2F4-p130-histone deacetylase complexes dissociate from, while activating species (E2F1, -2, and -3) associate with, target promoters. Histones H3 and H4 simultaneously become hyperacetylated, but it remains unclear whether this is a prerequisite or a consequence of E2F binding. Here, we show that activating E2F species are required for
Phosphorylation of HPV-16 E2 at Serine 243 Enables Binding to Brd4 and Mitotic Chromosomes
Chang, Szu-Wei; Liu, Wei-Chen; Liao, Kuan-Yu; Tsao, Yeou-Ping; Hsu, Pang-Hung; Chen, Show-Li
The papillomavirus E2 protein is involved in the maintenance of persistent infection and known to bind either to cellular factors or directly to mitotic chromosomes in order to partition the viral genome into the daughter cells. However, how the HPV-16 E2 protein acts to facilitate partitioning of the viral genome remains unclear. In this study, we found that serine 243 of HPV-16 E2, located in the hinge region, is crucial for chromosome binding during mitosis. Bromodomain protein 4 (Brd4) has been identified as a cellular binding target through which the E2 protein of bovine papillomavirus type 1 (BPV-1) tethers the viral genome to mitotic chromosomes. Mutation analysis showed that, when the residue serine 243 was substituted by glutamic acid or aspartic acid, whose negative charges mimic the effect of constitutive phosphorylation, the protein still can interact with Brd4 and colocalize with Brd4 in condensed metaphase and anaphase chromosomes. However, substitution by the polar uncharged residues asparagine or glutamine abrogated Brd4 and mitotic chromosome binding. Moreover, following treatment with the inhibitor JQ1 to release Brd4 from the chromosomes, Brd4 and E2 formed punctate foci separate from the chromosomes, further supporting the hypothesis that the association of the HPV-16 E2 protein with the chromosomes is Brd4-dependent. In addition, the S243A E2 protein has a shorter half-life than the wild type, indicating that phosphorylation of the HPV-16 E2 protein at serine 243 also increases its half-life. Thus, phosphorylation of serine 243 in the hinge region of HPV-16 E2 is essential for interaction with Brd4 and required for host chromosome binding. PMID:25340539
5. Espais afins euclidians 5.1 Considerem en un pla afi euclidi`a una refer`encia {O; e1, e2} on e1e2 = 60
Casacuberta, Carles
5. Espais afins euclidians 5.1 Considerem en un pla af´i euclidi`a una refer`encia {O; e1, e2} on e. Calculeu les coordenades de la projecci´o ortogonal del punt (1, -2, 3) sobre el pla x - y + 2z = 0 entre ells. Trobeu la dist`ancia del punt al pla en tots dos casos. 5.3 Sigui {O; e1, e2, e3} una refer
Differential gene expression in response to methoxychlor and estradiol through ERalpha, ERbeta, and AR in reproductive tissues of female mice.
Waters, K M; Safe, S; Gaido, K W
The reproductive and developmental effects of 17beta-estradiol (E2) and methoxychlor (MXC) observed in treated rodents appear to be linked to some unique but also overlapping patterns of gene expression. The MXC metabolite 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (HPTE) was previously shown to have selective agonist activity through estrogen receptor alpha (ERalpha) and antagonist activity through ERbeta and androgen receptor (AR). To discover gene families regulated by HPTE and E2, and to characterize similarities and differences in patterns of gene expression induced by these selective ER ligands, we analyzed tissues from mice treated for 3 days with a combined treatment of E2 and HPTE (E2 + HPTE), or the antiandrogen flutamide (FLU). RNA from uteri and ovaries was analyzed with cDNA microarrays and real-time RT-PCR. Results indicate that HPTE and E2 acted similarly to regulate most gene families in the uterus, which expresses predominantly ERalpha. However, in both the uterus and the ovary, there were a few genes that displayed differential patterns of gene regulation by E2 or HPTE treatment, presumably through ERbeta, AR, or other unidentified pathways. In the uterus, progesterone receptor, ERalpha, AR, insulin-like growth factor 1, insulin-like growth factor binding protein 5, and clusterin mRNAs were significantly reduced with both E2 or HPTE treatments, whereas cathepsin B was induced. Conversely, in the ovary, induction of cathepsin B by E2 was reversed after cotreatment with HPTE, and ERbeta expression was induced similarly by HPTE and FLU but not by E2. In addition, E2 uniquely regulated glutathione peroxidase 3, glutathione S-transferase, and cytochrome P450 17alpha-hydroxylase, with no effect of HPTE or FLU treatments. This analysis demonstrated several gene families that appear to be regulated in a ligand-specific pattern, which may explain the unique but overlapping reproductive tissue pathologies following exposure to E2 and MXC. PMID:11509743
Generalization of the differential equation model for both B (E 2 ) ? and the excitation energy E (g .s . ?21+) of even-even nuclei, and its application to the study of the B (E 2 ) problem in 46Ar
NASA Astrophysics Data System (ADS)
Nayak, R. C.; Pattnaik, S.
We generalize the recently developed differential equation model for the reduced quadrupole transition probability B (E 2 ) ? to include the corresponding excitation energy E 2 for the transition from the ground state to the first 2+ state of a given even-even nucleus. Accordingly both these quantities of a given nucleus can satisfy a common differential equation, in which both of them individually can be expressed in terms of their derivatives with respect to the neutron and proton numbers. We use this equation to obtain two recursion relations in both of them connecting in each case three neighboring even-even nuclei from lower- to higher-mass numbers and vice versa. Then we demonstrate their numerical validity using the available E 2 data throughout the nuclear chart and also explore their possible utility in predicting the unknown E 2 values. Finally we apply the model to analyze ``the B (E 2 ) problem in 46Ar," which refers to the recent experimental observation of a large B (E 2 ) value contradicting its prevailing value.
Seniority, collectivity, and B(E2) enhancement in 72Ni
NASA Astrophysics Data System (ADS)
Chiara, C. J.; Walters, W. B.; Stefanescu, I.; Alcorta, M.; Carpenter, M. P.; Fornal, B.; Gürdal, G.; Hoffman, C. R.; Janssens, R. V. F.; Kay, B. P.; Kondev, F. G.; Królas, W.; Lauritsen, T.; Lister, C. J.; McCutchan, E. A.; Paw?at, T.; Rogers, A. M.; Seweryniak, D.; Sharp, N.; Wrzesi?ski, J.; Zhu, S.
Gamma rays assigned to 2872Ni44 have been identified with Gammasphere in deep-inelastic reactions involving a 450-MeV 76Ge beam and a 198Pt target. Using a combination of spectra produced by double gates on the known 454-, 843-, and 1095-keV members of the ground-state cascade, a coincident line at 199 keV has been identified and is tentatively assigned as the 8+?6+ transition. These ?-ray coincidences have been observed only in prompt events, indicating an 8+ half-life below 20 ns and requiring a large B(E2) enhancement compared to that expected from a seniority scheme. This value is consistent with models showing decay to a seniority ?=4, 6+ level that is depressed by the same two-body interaction responsible for the rather low 1095-keV 21+ energy, as compared to the valence-symmetry counterpart 4494Ru50.
B(E2) Transition Strengths of Neutron-rich Carbon Isotopes in a Seniority Scheme
NASA Astrophysics Data System (ADS)
Macchiavelli, A. O.; Petri, M.; Fallon, P.; Clark, R. M.; Cromaz, M.; Lee, I.-Y.; Paschalis, S.
Lifetime measurements of 16 , 18 , 20C isotopes using the DSAM technique have been recently carried out at NSCL,. The new data provide unique information about the structure of the Carbon isotopes. In this work we attempt to interpret the derived B(E2) transitions strengths in terms of a seniority inspired scheme. The analysis shows an important role played by proton excitations due to an effective reduction of the p3/2 - p1/2 spin-orbit splitting. The predicted behavior of spectroscopic factors for proton removal and magnetic moments can be tested experimentally. Supported by U.S. DOE under contract DE-AC02-05CH11231.
Up-regulation of cyclooxygenase-2 by product-prostaglandin E2
NASA Technical Reports Server (NTRS)
Tjandrawinata, R. R.; Hughes-Fulford, M.
The development of prostate cancer has been linked to high level of dietary fat intake. Our laboratory investigates the connection between cancer cell growth and fatty acid products. Studying human prostatic carcinoma PC-3 cells, we found that prostaglandin E2 (PGE2) increased cell growth and up-regulated the gene expression of its own synthesizing enzyme, cyclooxygenase-2 (COX-2). PGE2 increased COX-2 mRNA expression dose-dependently with the highest levels of stimulation seen at the 3-hour period following PGE2 addition. The NSAID flurbiprofen (5 microM), in the presence of exogenous PGE2, inhibited the up-regulation of COX-2 mRNA and cell growth. These data suggest that the levels of local intracellular PGE2 play a major role in the growth of prostate cancer cells through an activation of COX-2 gene expression.
E2-quasi-exact solvability for non-Hermitian models
NASA Astrophysics Data System (ADS)
Fring, Andreas
We propose the notion of E2-quasi-exact solvability and apply this idea to find explicit solutions to the eigenvalue problem for a non-Hermitian Hamiltonian system depending on two parameters. The model considered reduces to the complex Mathieu Hamiltonian in a double scaling limit, which enables us to compute the exceptional points in the energy spectrum of the latter as a limiting process of the zeros for some algebraic equations. The coefficient functions in the quasi-exact eigenfunctions are univariate polynomials in the energy obeying a three-term recurrence relation. The latter property guarantees the existence of a linear functional such that the polynomials become orthogonal. The polynomials are shown to factorize for all levels above the quantization condition leading to vanishing norms rendering them to be weakly orthogonal. In two concrete examples we compute the explicit expressions for the Stieltjes measure.
Characterization of lipophilicity and antiproliferative activity of E-2-arylmethylene-1-tetralones and their heteroanalogues.
Hallgas, B; Dobos, Zs; Osz, E; Hollósy, F; Schwab, R E; Szabó, E Z; Eros, D; Idei, M; Kéri, Gy; Lóránd, T
A molecular library based on E-2-arylmethylene-1-tetralone has been designed and synthesized. A reversed phase high performance liquid chromatographic (RP-HPLC) method has been developed and applied to separate them and to characterize their lipophilicity. The chromatographic method applied here was suitable to separate the structural (ortho and para) isomers of compounds and was sensitive enough to differentiate their lipophilicities. The measured (k') and computer calculated (CLOGP) lipophilicity values has been compared. Good linear correlation has been found in the case of these structurally related molecules. In vitro biological assay has been performed with Methylene blue dying to investigate the antiproliferative potency of the compounds synthesized in this work. The measured (k') and calculated (CLOGP) lipophilicities of the compounds were compared with the antiproliferative activities and an optimum value of lipophilicity has been found for these compounds. PMID:15833292
Dynamical (e,2e) studies of tetrahydropyran and 1,4-dioxane
Builth-Williams, J. D.; Chiari, L.; Jones, D. B., E-mail: firstname.lastname@example.com, E-mail: firstname.lastname@example.com [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Silva, G. B. da [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Universidade Federal de Mato Grosso, Barra do Garças, MT 78600-000 (Brazil); Chaluvadi, Hari; Madison, D. H. [Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409 (United States); Brunger, M. J., E-mail: email@example.com, E-mail: firstname.lastname@example.com [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia)
We present experimental and theoretical results for the electron-impact ionization of the highest occupied molecular orbitals of tetrahydropyran and 1,4-dioxane. Using an (e,2e) technique in asymmetric coplanar kinematics, angular distributions of the slow ejected electron, with an energy of 20 eV, are measured when incident electrons at 250 eV ionize the target and scatter through an angle of either ?10° or ?15°. The data are compared with calculations performed at the molecular 3-body distorted wave level. Fair agreement between the theoretical model and the experimental measurements was observed. The similar structures for these targets provide key insights for assessing the limitations of the theoretical calculations. This study in turn facilitates an improved understanding of the dynamics in the ionization process.
In vitro prostaglandin E2 stimulation of /sup 45/Ca mobilization from chick bone
Satterlee, D.G.; Amborski, G.F.; McIntyre, M.D.; Parker, M.S.; Jacobs-Perry, L.A.
The ability of prostaglandin E2 (PGE2) to mobilize /sup 45/Ca from chick embryo long bones was assayed in an in vitro bone culture system. Concentrations of PGE2 tested ranged from 10(-9) to 10(-5) M. The PGE2 was effective in stimulating release of /sup 45/Ca from prelabelled bones at all concentrations tested except at 10(-9) M. In addition, stimulation of /sup 45/Ca release could be produced daily for 4 consecutive days of PGE2 culture-pulsing at what appeared to be the optimal PGE2 concentration, 10(-7) M. The authors conclude, as in mammals, PGE2 is a potent stimulator of calcium mobilization from avian bone. The potential involvement of prostaglandins in eggshell formation is discussed.
Dynamical (e,2e) investigations of tetrahydrofuran and tetrahydrofurfuryl alcohol as DNA analogues
NASA Astrophysics Data System (ADS)
Jones, D. B.; Builth-Williams, J. D.; Bellm, S. M.; Chiari, L.; Chaluvadi, H.; Madison, D. H.; Ning, C. G.; Lohmann, B.; Ingólfsson, O.; Brunger, M. J.
Triple differential cross section measurements for the electron-impact ionization of the highest occupied molecular orbital of tetrahydrofuran (THF) are reported. Experimental measurements were performed using the (e,2e) technique in asymmetric coplanar kinematics with an incident electron energy of 250 eV and an ejected electron energy of 20 eV. With the scattered electrons being detected at -5°, the angular distribution of the ejected electrons was observed. These measurements are compared with calculations performed within the molecular 3-body distorted wave (M3DW) model, and against previous measurements on THF and tetrahydrofurfuryl alcohol to further understand the role that kinematics and structure play in electron-impact ionization.
Spectroscopic study and structure of ( E)-2-[(2-chlorobenzylimino)methyl]methoxyphenol
NASA Astrophysics Data System (ADS)
Ünver, Hüseyin; Y?ld?z, Mustafa; Özay, Hava; Durlu, Tahsin Nuri
( E)-2-[(2-Chlorobenzylimino)methyl]methoxyphenol has been synthesized from the reaction of 2-hydroxy-3-methoxy-1-benzaldehyde( o-vanillin) with 2-chlorobenzylamine. The title compound has been characterized by using elemental analysis, FT-IR, 1H NMR, 13C NMR and UV-vis spectroscopic techniques. The crystal structure of the title compound has also been examined cyrstallographically. It crystallizes in the orthorhombic space group Pbca with unit cell parameters: a = 7.208(1) Ĺ, b = 13.726(2) Ĺ, c = 27.858(4) Ĺ, V = 2756.0(1) Ĺ 3, Dc = 1.18 g cm -3 and Z = 8. The crystal structure was solved by direct methods and refined by full-matrix least squares to a find R = 0.046 for 2773 observed reflections.
Phenomenological analysis of B (E 2 ) transition strengths in neutron-rich carbon isotopes
NASA Astrophysics Data System (ADS)
Macchiavelli, A. O.; Petri, M.; Fallon, P.; Paschalis, S.; Clark, R. M.; Cromaz, M.; Lee, I. Y.
Recent experimental results related to the quadrupole collectivity in neutron-rich carbon isotopes are analyzed in a phenomenological approach. B (E 2 ;21+?01+) transitions rates derived from lifetime measurements are interpreted in terms of the mixing of basic neutron and proton 2+ excitations. A seniority inspired scheme is used to describe the neutron component. The observed increase in collectivity can be explained with a corresponding increased role of proton excitations. This is likely due to the reduction of the proton p3 /2-p1 /2 spin-orbit splitting caused by the tensor and two-body spin-orbit components of the force between the protons and the added neutrons in the (d5 /2+s1 /2 ) shells.
Mutations in the Gene Encoding the E2 Conjugating Enzyme UBE2T Cause Fanconi Anemia.
Hira, Asuka; Yoshida, Kenichi; Sato, Koichi; Okuno, Yusuke; Shiraishi, Yuichi; Chiba, Kenichi; Tanaka, Hiroko; Miyano, Satoru; Shimamoto, Akira; Tahara, Hidetoshi; Ito, Etsuro; Kojima, Seiji; Kurumizaka, Hitoshi; Ogawa, Seishi; Takata, Minoru; Yabe, Hiromasa; Yabe, Miharu
Fanconi anemia (FA) is a rare genetic disorder characterized by genome instability, increased cancer susceptibility, progressive bone marrow failure (BMF), and various developmental abnormalities resulting from the defective FA pathway. FA is caused by mutations in genes that mediate repair processes of interstrand crosslinks and/or DNA adducts generated by endogenous aldehydes. The UBE2T E2 ubiquitin conjugating enzyme acts in FANCD2/FANCI monoubiquitination, a critical event in the pathway. Here we identified two unrelated FA-affected individuals, each harboring biallelic mutations in UBE2T. They both produced a defective UBE2T protein with the same missense alteration (p.Gln2Glu) that abolished FANCD2 monoubiquitination and interaction with FANCL. We suggest this FA complementation group be named FA-T. PMID:26046368
MicroRNA-320 inhibits cell proliferation in glioma by targeting E2F1.
Sun, Ji-Yong; Xiao, Wei-Zhong; Wang, Fei; Wang, Yong-Qian; Zhu, You-Hou; Wu, Yi-Fang; Miao, Zeng-Li; Lin, Yu-Chang
MicroRNAs (miRs) are a class of small non-coding RNAs that are involved in the regulation of gene expression, and in cancer development and progression. In the present study, miR?320 expression was found to be significantly reduced in glioma tissue in comparison with that in adjacent healthy tissues. In the present study, in vitro analyses demonstrated that overexpression of miR?320 inhibited cell proliferation and metastasis, while antisense miR?320 oligonucleotides enhanced cell proliferation and migration in U251 and SHG?44 glioma cell lines, compared with that in negative control cells. Protein expression of E2F1, a cell?cycle regulator, was negatively regulated by miR?320. Therefore, the present study provides novel insights into the association between miR-320 and glioma development. PMID:25901521
Polarization effect in (e, 2e) reaction process for Ar (3s) in coplanar asymmetric geometry
NASA Astrophysics Data System (ADS)
Zhou, Li-Xia; Wang, Dian-Sheng; Yan, You-Guo; Wang, Cai-Ling
The (e, 2e) triple differential cross sections (TDCSs) of Ar (3s) are calculated by using distorted-wave Born approximation under coplanar asymmetric geometry. The incident electron energy is 113.5 eV, and the scattering electron angle ?1 is ?15°. The ejected electron energy is set at 10 eV, 7.5 eV, 5 eV, and 2 eV, respectively. The polarization effects have been discussed and the polarization potential Vpol changing from a second-order to a fourth-order term has been analyzed. Our calculated TDCSs have been compared with reported experimental and theoretical results, and the calculated TDCSs of polarization potential up to the fourth order could give a good fit with experimental results in the binary region, but fail to predict the correct recoil-to-binary ratio in most cases.
Investigation of the E2 and E3 matrix elements in 200Hg using inelastic scattering
NASA Astrophysics Data System (ADS)
Rand, E. T.; Garrett, P. E.; Ball, G. C.; Bildstein, V.; Faestermann, T.; Hadinia, B.; Hertenberger, R.; Jamieson, D. S.; Jigmeddorj, B.; Leach, K. G.; Svensson, C. E.; Wirth, H.-F.
A nuclear structure campaign has been initiated to investigate the isotopes of mercury near A = 199. Currently 199Hg provides the most stringent limit on an atomic electric dipole moment (EDM). The observation of a permanent EDM would represent a clear signal of CP violation from new physics beyond the Standard Model. Theoretical calculations for 199Hg are very difficult and give varied predictions for the excited-state spectrum. Understanding the E2 and E3 strengths in the neighbouring even-even isotopes of mercury will make it possible to develop a nuclear structure model for the Schiff strength based on these matrix elements, and thereby constrain present model predictions of the contribution of octupole collectivity to the Schiff moment of the nucleus.
Measurement of e+e-??+?-? (2 S ) via initial state radiation at Belle
NASA Astrophysics Data System (ADS)
Wang, X. L.; Yuan, C. Z.; Shen, C. P.; Wang, P.; Abdesselam, A.; Adachi, I.; Aihara, H.; Al Said, S.; Arinstein, K.; Asner, D. M.; Ayad, R.; Bakich, A. M.; Bansal, V.; Bhuyan, B.; Bobrov, A.; Bonvicini, G.; Bra?ko, M.; Browder, T. E.; ?ervenkov, D.; Chang, P.; Chekelian, V.; Chen, A.; Cheon, B. G.; Chilikin, K.; Chistov, R.; Cho, K.; Chobanova, V.; Choi, S.-K.; Choi, Y.; Cinabro, D.; Dalseno, J.; Danilov, M.; Doležal, Z.; Drásal, Z.; Drutskoy, A.; Dutta, K.; Eidelman, S.; Farhat, H.; Fast, J. E.; Ferber, T.; Gaur, V.; Garmash, A.; Getzkow, D.; Gillard, R.; Goh, Y. M.; Haba, J.; Hayasaka, K.; Hayashii, H.; He, X. H.; Hou, W.-S.; Iijima, T.; Inami, K.; Ishikawa, A.; Itoh, R.; Iwasaki, Y.; Joffe, D.; Julius, T.; Kang, K. H.; Kato, E.; Kawasaki, T.; Kiesling, C.; Kim, D. Y.; Kim, H. J.; Kim, J. B.; Kim, J. H.; Kim, M. J.; Kim, S. H.; Kim, Y. J.; Kinoshita, K.; Ko, B. R.; Kodyš, P.; Korpar, S.; Križan, P.; Krokovny, P.; Kuzmin, A.; Kwon, Y.-J.; Lange, J. S.; Lee, I. S.; Lewis, P.; Li, Y.; Li Gioi, L.; Libby, J.; Liventsev, D.; Lukin, P.; Matvienko, D.; Miyabayashi, K.; Miyata, H.; Mizuk, R.; Moll, A.; Mori, T.; Mussa, R.; Nakano, E.; Nakao, M.; Nanut, T.; Natkaniec, Z.; Nisar, N. K.; Nishida, S.; Ogawa, S.; Okuno, S.; Olsen, S. L.; Pakhlov, P.; Pakhlova, G.; Park, C. W.; Park, H.; Pedlar, T. K.; Pestotnik, R.; Petri?, M.; Piilonen, L. E.; Ribežl, E.; Ritter, M.; Rostomyan, A.; Ryu, S.; Sakai, Y.; Sandilya, S.; Santelj, L.; Sanuki, T.; Savinov, V.; Schneider, O.; Schnell, G.; Schwanda, C.; Semmler, D.; Senyo, K.; Shebalin, V.; Shibata, T.-A.; Shiu, J.-G.; Sibidanov, A.; Simon, F.; Sohn, Y.-S.; Sokolov, A.; Solovieva, E.; Stari?, M.; Steder, M.; Sumiyoshi, T.; Tamponi, U.; Tanida, K.; Tatishvili, G.; Teramoto, Y.; Trabelsi, K.; Uchida, M.; Uglov, T.; Unno, Y.; Uno, S.; Usov, Y.; Van Hulse, C.; Vanhoefer, P.; Varner, G.; Vinokurova, A.; Wagner, M. N.; Watanabe, Y.; Won, E.; Yashchenko, S.; Yusa, Y.; Zhang, Z. P.; Zhilich, V.; Zupanc, A.; Belle Collaboration
We report measurement of the cross section of e+e-??+?-? (2 S ) between 4.0 and 5.5 GeV, based on an analysis of initial state radiation events in a 980 fb-1 data sample recorded with the Belle detector. The properties of the Y (4360 ) and Y (4660 ) states are determined. Fitting the mass spectrum of ?+?-? (2 S ) with two coherent Breit-Wigner functions, we find two solutions with identical mass and width but different couplings to electron-positron pairs: MY (4360 )=(4347 ±6 ±3 ) MeV /c2 , ?Y (4360 )=(103 ±9 ±5 ) MeV , MY (4660 )=(4652 ±10 ±8 ) MeV /c2 , ?Y (4660 )=(68 ±11 ±1 ) MeV ; and B [Y (4360 )??+?-? (2 S )].?Y(4360 ) e+e-=(10.9 ±0.6 ±0.7 ) eV and B [Y (4660 )??+?-? (2 S )].?Y(4660 ) e+e-=(8.1 ±1.1 ±0.5 ) eV for one solution; or B [Y (4360 )??+?-? (2 S )].?Y(4360 ) e+e-=(9.2 ±0.6 ±0.6 ) eV and B [Y (4660 )??+?-? (2 S )].?Y(4660 ) e+e-=(2.0 ±0.3 ±0.2 ) eV for the other. Here, the first errors are statistical and the second systematic. Evidence for a charged charmoniumlike structure at 4.05 GeV /c2 is observed in the ?±? (2 S ) intermediate state in the Y (4360 ) decays.
E-2-hexenal promotes susceptibility to Pseudomonas syringae by activating jasmonic acid pathways in Arabidopsis
Scala, Alessandra; Mirabella, Rossana; Mugo, Cynthia; Matsui, Kenji; Haring, Michel A.; Schuurink, Robert C.
Green leaf volatiles (GLVs) are C6-molecules – alcohols, aldehydes, and esters – produced by plants upon herbivory or during pathogen infection. Exposure to this blend of volatiles induces defense-related responses in neighboring undamaged plants, thus assigning a role to GLVs in regulating plant defenses. Here we compared Arabidopsis thaliana ecotype Landsberg erecta (Ler) with a hydroperoxide lyase line, hpl1, unable to synthesize GLVs, for susceptibility to Pseudomonas syringae pv. tomato (DC3000). We found that the growth of DC3000 was significantly reduced in the hpl1 mutant. This phenomenon correlated with lower jasmonic acid (JA) levels and higher salicylic acid levels in the hpl1 mutant. Furthermore, upon infection, the JA-responsive genes VSP2 and LEC were only slightly or not induced, respectively, in hpl1. This suggests that the reduced growth of DC3000 in hpl1 plants is due to the constraint of JA-dependent responses. Treatment of hpl1 plants with E-2-hexenal, one of the more reactive GLVs, prior to infection with DC3000, resulted in increased growth of DC3000 in hpl1, thus complementing this mutant. Interestingly, the growth of DC3000 also increased in Ler plants treated with E-2-hexenal. This stronger growth was not dependent on the JA-signaling component MYC2, but on ORA59, an integrator of JA and ethylene signaling pathways, and on the production of coronatine by DC3000. GLVs may have multiple effects on plant–pathogen interactions, in this case reducing resistance to Pseudomonas syringae via JA and ORA59. PMID:23630530
Cell type specific transcriptional activities among different papillomavirus long control regions and their regulation by E2
Ottinger, Matthias; Smith, Jennifer A.; Schweiger, Michal-Ruth; Robbins, Dana; Powell, Maria L.C.; You, Jianxin; Howley, Peter M.
This study systematically examined the viral long control region (LCR) activities and their responses to E2 for human papillomavirus (HPV) types 11. 16 and 18 as well as bovine papillomavirus 1 (BPV1) in a number of different cell types, including human cervical cancer cell lines, human oral keratinocytes, BJ fibroblasts, as well as CV1 cells. The study revealed cell- and virus-type specific differences among the individual LCRs and their regulation by E2. In addition, the integration of the LCR into the host genome was identified as a critical determinant for LCR activity and its response to E2. Collectively, these data indicate a more complex level of transcriptional regulation of the LCR by cellular and viral factors than previously appreciated, including a comparatively low LCR activity and poor E2 responsive for HPV16 in most human cells. This study should provide a valuable framework for future transcriptional studies in the papillomavirus field. PMID:19836046
76 FR 71044 - International Conference on Harmonisation; E2B(R3) Electronic Transmission of Individual Case...
Federal Register 2010, 2011, 2012, 2013, 2014
...Case Safety Reports; Draft Guidance on Implementation; Data Elements and Message Specification; Appendix on Backwards and Forwards...Case Safety Reports (ICSRs): Implementation Guide--Data Elements and Message Specification'' (the draft E2B(R3)...
40 CFR Table E-2 to Subpart E of... - Spectral Energy Distribution and Permitted Tolerance for Conducting Radiative Tests
Code of Federal Regulations, 2012 CFR
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40 CFR Table E-2 to Subpart E of... - Spectral Energy Distribution and Permitted Tolerance for Conducting Radiative Tests
Code of Federal Regulations, 2014 CFR
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40 CFR Table E-2 to Subpart E of... - Spectral Energy Distribution and Permitted Tolerance for Conducting Radiative Tests
Code of Federal Regulations, 2011 CFR
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40 CFR Table E-2 to Subpart E of... - Spectral Energy Distribution and Permitted Tolerance for Conducting Radiative Tests
Code of Federal Regulations, 2010 CFR
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40 CFR Table E-2 to Subpart E of... - Spectral Energy Distribution and Permitted Tolerance for Conducting Radiative Tests
Code of Federal Regulations, 2013 CFR
...2013-07-01 false Spectral Energy Distribution and Permitted Tolerance for Conducting Radiative Tests E Table E-2 to Subpart E of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...
Evaluation of multiple antigenic peptides based on the Chikungunya E2 protein for improved serological diagnosis of infection.
Bhatnagar, Santwana; Kumar, Pradeep; Mohan, Teena; Verma, Priyanka; Parida, M M; Hoti, S L; Rao, D N
In recent years, Chikungunya virus (CHIKV) reemerged and numerous outbreaks were reported all over the world. After screening CHIKV-positive sera, we had already reported many dominant epitopes within the envelope E2 protein of CHIKV. In the present study, we aimed at developing a highly sensitive immunodiagnostic assay for CHIKV based on a multiple antigenic peptide (MAP) approach using selective epitopes of the E2 protein. MAPs in four different E2 peptide combinations were screened with CHIKV-positive sera. The MAPs reacted with all CHIKV-positive sera and no reactivity was seen with healthy or dengue-positive sera. Our results indicate that MAP 1 seems to be an alternate antigen to full-length protein E2 for immunodiagnosis of CHIKV infections with high sensitivity and specificity. PMID:25412351
The roles of Rb, p107, and E2f4 in bone formation and embryonic development
Berman, Seth D
The pocket proteins, through their interaction with the E2F transcription factors, ensure the proper regulation of cell proliferation. By doing so, these protein complexes affect other fundamental processes such as ...
TIP49, but not TRRAP, modulates c-Myc and E2F1 dependent apoptosis Kerri A Dugan1
Wood, Marcelo A.
TIP49, but not TRRAP, modulates c-Myc and E2F1 dependent apoptosis Kerri A Dugan1 , Marcelo A Wood1 modulates c-Myc-mediated apoptosis whereas disruption of TRRAP activity has no apparent effect on apoptosis differentially potentiate c-Myc and E2F1 functions. Oncogene (2002) 21, 5835 5843. doi:10.1038/sj.onc. 1205763
The Effect of Thyroid Hormone, Prostaglandin E2, and Calcium Gluconate on Orthodontic Tooth Movement and Root Resorption in Rats
Seifi, Massoud; Hamedi, Roya; Khavandegar, Zohre
Statement of the Problem A major objective of investigators is to clarify the role of metabolites in achievement of maximum tooth movement with minimal root damage during orthodontic tooth movement (OTM). Purpose The aim of this study was to determine the effect of administration of thyroid hormone, prostaglandin E2, and calcium on orthodontic tooth movement and root resorption in rats. Materials and Method Sixty four male Wistar rats were randomly divided into 8 groups of eight rats each: 1- 20µg/kg thyroxine was injected in traperitoneally after installation of the orthodontic appliance. 2- 0.1 ml of 1 mg/ml prostaglandin E2 was injected submucosally. 3- 10% (200 mg/kg) calcium gluconate was injected. 4- Prostaglandin E2 was injected submucosally and 10% calcium was injected intraperitoneally. 5- Thyroxine was injected intraperitoneally and prostaglandin E2 was injected submucosally. 6- 20µg/kg thyroxine with calcium was injected. 7- Prostaglandin E2 was injected submucosally with calcium and thyroxine. 8- Distilled water was used in control group. The orthodontic appliances comprised of a NiTi closed coil were posteriorly connected to the right first molar and anteriorly to the upper right incisor. OTM was measured with a feeler gauge. The mid-mesial root of the first molar and the adjacent tissues were histologically evaluated. The Data were analyzed by one-way ANOVA and Student-Newman-Keuls test. Results The highest mean OTM was observed in the thyroxine and prostaglandin E2 group (Mean±SD = 0.7375±0.1359 mm) that was significantly different (p< 0.05). A significant difference (p< 0.05) in root resorption was observed between the prostaglandin E2 (0.0192±0.0198 mm2) and the other groups. Conclusion It seems that the combination of thyroxine and prostaglandin E2, with a synergistic effect, would decrease the root resorption and increase the rate of orthodontic tooth movement in rats.
Hepatitis C Virus Protects Human B Lymphocytes from Fas-Mediated Apoptosis via E2-CD81 Engagement
Tong, Yimin; Hua, Xian; Zhu, Fenghui; Huang, Libin; Liu, Yuan; Luo, Yuan; Lu, Wei; Zhao, Ping; Qi, Zhongtian
HCV infection is often associated with B-cell regulatory control disturbance and delayed appearance of neutralizing antibodies. CD81 is a cellular receptor for HCV and can bind to HCV envelope protein 2 (E2). CD81 also participates to form a B cell costimulatory complex. To investigate whether HCV influences B cell activation and immune function through E2 -CD81 engagement, here, human Burkitt's lymphoma cell line Raji cells and primary human B lymphocytes (PHB) were treated with HCV E2 protein and cell culture produced HCV particles (HCVcc), and then the related cell phenotypes were assayed. The results showed that both E2 and HCVcc triggered phosphorylation of I?B?, enhanced the expression of anti-apoptosis Bcl-2 family proteins, and protected Raji cells and PHB cells from Fas-mediated death. In addition, both E2 protein and HCVcc increased the expression of costimulatory molecules CD80, CD86 and CD81 itself, and decreased the expression of complement receptor CD21. The effects were dependent on E2-CD81 interaction on the cell surface, since CD81-silenced Raji cells did not respond to both treatments; and an E2 mutant that lose the CD81 binding activity, could not trigger the responses of both Raji cells and PHB cells. The effects were not associated with HCV replication in cells, for HCV pseudoparticle (HCVpp) and HCVcc failed to infect Raji cells. Hence, E2-CD81 engagement may contribute to HCV-associated B cell lymphoproliferative disorders and insufficient neutralizing antibody production. PMID:21526201
Oncolytic adenovirus armed with human papillomavirus E2 gene in combination with radiation demonstrates synergistic enhancements of antitumor efficacy
W Wang; X Xia; S Wang; N Sima; Y Li; Z Han; Q Gao; A Luo; K Li; L Meng; J Zhou; C Wang; K Shen; D Ma
High-risk human papillomavirus (hr-HPV) E6 and E7 oncogenes are associated with resistance to radiotherapy in cervical cancer. Efforts have been taken to employ HPV E2, a crucial negative transcriptional modulator of HPV E6 and E7 oncogenes, and also an apoptosis-inducing agent, for therapeutic intervention. Despite being conceptually attractive, the potency and feasibility of current hr-HPV E2-based therapies remain limited. Here,
Mapping B-Cell Epitopes of Hepatitis C Virus E2 Glycoprotein Using Human Monoclonal Antibodies from Phage Display Libraries
Clinical and experimental evidence indicates that the hepatitis C virus (HCV) E2 glycoprotein (HCV\\/E2) is the most promising candidate for the development of an effective anti-HCV vaccine. Identification of the human epitopes that are conserved among isolates and are able to elicit protective antibodies would constitute a significant step forward. This work describes the mapping of the B-cell epitopes present
The prostaglandin E2 receptor-1 (EP1) mediates acid-induced visceral pain hypersensitivity in humans
Sanchoy Sarkar; Anthony R. Hobson; Andrew Hughes; Jim Growcott; Clifford J. Woolf; David G. Thompson; Qasim Aziz
Background & Aims: Central sensitization, an activity-dependent increase in spinal cord neuronal excitability, has been shown to contribute to esophageal pain hypersensitivity. Prostaglandin E2 (PGE2) is a mediator in both peripheral and central sensitization, in part via the prostaglandin E2 receptor-1 (EP-1), and may be a potential target for treating visceral pain. The purpose of this study was to determine
Comprehensive mapping of common immunodominant epitopes in the eastern equine encephalitis virus E2 protein recognized by avian antibody responses.
Sun, Encheng; Zhao, Jing; Sun, Liang; Xu, Qingyuan; Yang, Tao; Qin, Yongli; Wang, Wenshi; Wei, Peng; Sun, Jing; Wu, Donglai
Eastern equine encephalitis virus (EEEV) is a mosquito-borne virus that can cause both human and equine encephalitis with high case fatality rates. EEEV can also be widespread among birds, including pheasants, ostriches, emu, turkeys, whooping cranes and chickens. The E2 protein of EEEV and other Alphaviruses is an important immunogenic protein that elicits antibodies of diagnostic value. While many therapeutic and diagnostic applications of E2 protein-specific antibodies have been reported, the specific epitopes on E2 protein recognized by the antibody responses of different susceptible hosts, including avian species, remain poorly defined. In the present study, the avian E2-reactive polyclonal antibody (PAb) response was mapped to linear peptide epitopes using PAbs elicited in chickens and ducks following immunization with recombinant EEEV E2 protein and a series of 42 partially overlapping peptides covering the entire EEEV E2 protein. We identified 12 and 13 peptides recognized by the chicken and duck PAb response, respectively. Six of these linear peptides were commonly recognized by PAbs elicited in both avian species. Among them five epitopes recognized by both avian, the epitopes located at amino acids 211-226 and 331-352 were conserved among the EEEV antigenic complex, but not other associated alphaviruses, whereas the epitopes at amino acids 11-26, 30-45 and 151-166 were specific to EEEV subtype I. The five common peptide epitopes were not recognized by avian PAbs against Avian Influenza Virus (AIV) and Duck Plague Virus (DPV). The identification and characterization of EEEV E2 antibody epitopes may be aid the development of diagnostic tools and facilitate the design of epitope-based vaccines for EEEV. These results also offer information with which to study the structure of EEEV E2 protein. PMID:23922704
Endocrine disruption and consequences of chronic exposure to ibuprofen in Japanese medaka (Oryzias latipes) and freshwater cladocerans Daphnia magna and Moina macrocopa.
Han, Sunyoung; Choi, Kyungho; Kim, Jungkon; Ji, Kyunghee; Kim, Sunmi; Ahn, Byeongwoo; Yun, Junheon; Choi, Kyunghee; Khim, Jong Seong; Zhang, Xiaowei; Giesy, John P
Despite frequent detection of ibuprofen in aquatic environments, the hazards associated with long-term exposure to ibuprofen have seldom been investigated. Ibuprofen is suspected of influencing sex steroid hormones through steroidogenic pathways in both vertebrates and invertebrates. In this study, the effect of ibuprofen on sex hormone balance and the associated mechanisms was investigated in vitro by use of H295R cells. We also conducted chronic toxicity tests using freshwater fish, Oryzias latipes, and two freshwater cladocerans, Daphnia magna and Moina macrocopa, for up to 144 and 21d of exposure, respectively. Ibuprofen exposure increased 17beta-estradiol (E2) production and aromatase activity in H295R cells. Testosterone (T) production decreased in a dose-dependent manner. For D. magna, the 48 h immobilization EC50 was 51.4 mg/L and the 21 d reproduction NOEC was <1.23 mg/L; for M. macrocopa, the 48 h immobilization EC50 was 72.6 mg/L and the 7d reproduction NOEC was 25mg/L. For O. latipes, 120 d survival NOEC was 0.0001 mg/L. In addition, ibuprofen affected several endpoints related to reproduction of the fish, including induction of vitellogenin in male fish, fewer broods per pair, and more eggs per brood. Parental exposure to as low as 0.0001 mg/L ibuprofen delayed hatching of eggs even when they were transferred to and cultured in clean water. Delayed hatching is environmentally relevant because this may increase the risk of being predated. For O. latipes, the acute-to-chronic ratio of ibuprofen was estimated to be greater than 1000. Overall, relatively high acute-to-chronic ratio and observation of reproduction damage in medaka fish at environmentally relevant ranges of ibuprofen warrant the need for further studies to elucidate potential ecological consequences of ibuprofen contamination in the aquatic environment. PMID:20236711
Lonidamine affects testicular steroid hormones in immature mice
Traina, Maria Elsa [Department of Drug Research and Evaluation, Istituto Superiore di Sanita, Viale Regina Elena, 299. 00161 Rome (Italy)]. E-mail: firstname.lastname@example.com; Guarino, Maria [Department of Drug Research and Evaluation, Istituto Superiore di Sanita, Viale Regina Elena, 299. 00161 Rome (Italy); Natoli, Alessia [Department of Drug Research and Evaluation, Istituto Superiore di Sanita, Viale Regina Elena, 299. 00161 Rome (Italy); Romeo, Antonella [Department of Drug Research and Evaluation, Istituto Superiore di Sanita, Viale Regina Elena, 299. 00161 Rome (Italy); Urbani, Elisabetta [Department of Drug Research and Evaluation, Istituto Superiore di Sanita, Viale Regina Elena, 299. 00161 Rome (Italy)
The effects on the hypothalamus-pituitary-testicular axis of the well-known antispermatogenic drug lonidamine (LND) has not been elucidated so far. In the present study, the possible changes of the testicular steroid hormones were evaluated in immature mice for a better characterization of the LND adverse effects both in its use as antitumoral agent and male contraceptive. Male CD1 mice were orally treated on postnatal day 28 (PND28) with LND single doses (0 or 100 mg/kg b.w.) and euthanized every 24 h from PND29 to PND32, on PND35 and on PND42 (1 and 2 weeks after the administration, respectively). Severe testicular effects were evidenced in the LND treated groups, including: a) significant testis weight increase, 24 h and 48 h after dosing; b) sperm head counts decrease (more than 50% of the control) on PND29-32; c) damage of the tubule morphology primarily on the Sertoli cell structure and germ cell exfoliation. All these reproductive endpoints were recovered on PND42. At the same time, a significant impairment of the testicular steroid balance was observed in the treated mice, as evidenced by the decrease of testosterone (T) and androstenedione (ADIONE) and the increase of 17OH-progesterone (17OH-P4) on the first days after dosing, while the testicular content of 17{beta}-estradiol (E2) was unchanged. The hormonal balance was not completely restored afterwards, as levels of T, ADIONE and 17OH-P4 tended to be higher in the treated mice than in the controls, on PND35 and PND42. These data showed for the first time that LND affects intratesticular steroids in experimental animals. However further data are needed both to elucidate the mechanism responsible for the impairment of these metabolic pathways and to understand if the androgens decrease observed after LND administration could be partially involved in the testicular damage.
Expression of R-ras oncogenes in the hermaphroditic fish Kryptolebias marmoratus, exposed to endocrine disrupting chemicals.
Rhee, Jae-Sung; Lee, Young-Mi; Raisuddin, Sheikh; Lee, Jae-Seong
The hermaphroditic fish Krytolebias marmoratus is a potential fish model for study of tumour development. Recently, sequences and expression of some oncogenes and tumor suppressor gene have been studied in K. marmoratus. To get a better understanding of oncogene expression at different development stage, and in different tissues three R-ras genes were cloned and fully sequenced. Expression of these R-ras genes (R-ras1, R-ras2, R-ras3) was also studied in fish exposed to endocrine-disrupting chemicals (EDCs). Liver showed the highest level of expression compared to other tissues, even though each R-ras gene showed different expression patterns in tissues. Interestingly, in secondary male (ovary atresia stage), expression levels of three R-ras genes was lower compared to hermaphrodites. At different developmental stages, R-ras2 gene showed most pronounced expression at early embryogenesis but at stage 5 (hatchling stage) and juvenile stage, R-ras3 gene showed the highest expression. After the juvenile stage, R-ras1 gene was upregulated compared to other R-ras genes, which showed the highest expression at the hermaphroditic stage. When fish were exposed to 17-beta-estradiol (E2), a natural estrogen and tamoxifen, a nonsteroidal estrogen antagonist and three EDCs viz., 4-n-nonylphenol (NP), bisphenol A (BPA), and 4-tert-octylphenol (OP), all the three R-ras genes were induced, except in the fish exposed to tamoxifen. These results suggest that EDCs modulate the expression of R-ras genes and thus affect subsequent signal transduction and tumor development. PMID:19000778
Androgen-metabolizing enzymes show region-specific changes across the breeding season in the brain of a wild songbird.
Soma, K K; Bindra, R K; Gee, J; Wingfield, J C; Schlinger, B A
The Lapland longspur (Calcarius lapponicus) is an arctic-breeding songbird that shows rapid behavioral changes during a short breeding season. Changes in plasma testosterone (T) in the spring are correlated with singing but not territorial aggression in males. Also, T treatment increases song but not aggression in this species. In contrast, in temperate-zone breeders, song and aggression are highly correlated, and both increase after T treatment. We asked whether regional or temporal differences in androgen-metabolizing enzymes in the longspur brain explain hormone-behavior patterns in this species. We measured the activities of aromatase, 5alpha-reductase and 5beta-reductase in free-living longspur males. Aromatase and 5alpha-reductase convert T into the active steroids 17beta-estradiol (E(2)) and 5alpha-dihydrotestosterone (5alpha-DHT), respectively. 5beta-Reductase deactivates T via conversion to 5beta-DHT, an inactive steroid. We examined seven brain regions at three stages in the breeding season. Overall, aromatase activity was high in the hypothalamus, hippocampus, and ventromedial telencephalon (containing nucleus taeniae, the avian homologue to the amygdala). 5beta-Reductase activity was high throughout the telencephalon. Activities of all three enzymes changed over time in a region-specific manner. In particular, aromatase activity in the rostral hypothalamus was decreased late in the breeding season, which may explain why T treatment at this time does not increase aggression. Changes in 5beta-reductase do not explain the effects of plasma T on aggressive behavior. PMID:10512976
Induction of cells differentiation and ABC transporters expression by a myco-estrogen, zearalenone, in human choriocarcinoma cell line (BeWo).
Prouillac, Caroline; Videmann, Bernadette; Mazallon, Michelle; Lecoeur, Sylvaine
The mycotoxin zearalenone, produced by Fusarium species, is a worldwide contaminant of concern in cereals and other plant products. Due to its estrogenic activity, zearalenone (ZEA) is known to have toxicological effect in animals on reproductive system and the placental transfer of ZEA was suggested by in vivo studies. Although passive diffusion is the principal transport mechanism across the placenta, several carrier-mediated transport protein such as ABC transporter (P-gp, MRP1, MRP2, BCRP) have been identified in the placenta. In this work, we have investigated the effect of ZEA on trophoblast differentiation and ABC transporter expression by using an in vitro model of transplacental barrier, the BeWo cell line. In the presence of 10 microM ZEA morphological (syncytium formation) and biochemical (hCG secretion) differentiation of BeWo cells were observed after a 48h exposure. Results were compared to 17beta-estradiol (E2) and an inducer of syncytialisation (forskolin). The influence of cell differentiation and ZEA exposure on expression profiles of major ABC transporters was investigated in BeWo cells: expression of mRNA MRP1, MRP2 and BCRP was induced after 24h of ZEA exposure. Induction of P-gp, MRP1, and MRP2 protein was observed after 48h of ZEA exposure. Similar results were obtained after forskolin exposure. Our study reported for the first time the implication of a food contaminant in biological effect and ABC transporter expression modulation in human choriocarcinoma cells. PMID:19580841
Visualization of VirE2 protein translocation by the Agrobacterium type IV secretion system into host cells.
Sakalis, Philippe A; van Heusden, G Paul H; Hooykaas, Paul J J
Type IV secretion systems (T4SS) can mediate the translocation of bacterial virulence proteins into host cells. The plant pathogen Agrobacterium tumefaciens uses a T4SS to deliver a VirD2-single stranded DNA complex as well as the virulence proteins VirD5, VirE2, VirE3, and VirF into host cells so that these become genetically transformed. Besides plant cells, yeast and fungi can efficiently be transformed by Agrobacterium. Translocation of virulence proteins by the T4SS has so far only been shown indirectly by genetic approaches. Here we report the direct visualization of VirE2 protein translocation by using bimolecular fluorescence complementation (BiFC) and Split GFP visualization strategies. To this end, we cocultivated Agrobacterium strains expressing VirE2 tagged with one part of a fluorescent protein with host cells expressing the complementary part, either fused to VirE2 (for BiFC) or not (Split GFP). Fluorescent filaments became visible in recipient cells 20-25 h after the start of the cocultivation indicative of VirE2 protein translocation. Evidence was obtained that filament formation was due to the association of VirE2 with the microtubuli. PMID:24376037
Estrogen Rapidly Activates the PI3K/AKT Pathway and Hypoxia-Inducible Factor 1 and Induces Vascular Endothelial Growth Factor A Expression in Luminal Epithelial Cells of the Rat Uterus1
Kazi, Armina A.; Molitoris, Kristin Happ; Koos, Robert D.
We have previously shown that 17beta-estradiol (E2) increases vascular endothelial growth factor A (Vegfa) gene expression in the rat uterus, resulting in increased microvascular permeability, and that this involves the simultaneous recruitment of hypoxia-inducible factor 1 (HIF1) and estrogen receptor alpha (ESR1) to the Vegfa gene promoter. Both events require the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway. However, those studies were carried out using whole uterine tissue, and while most evidence indicates that the likely site of E2-induced Vegfa expression is luminal epithelial (LE) cells, other studies have identified stromal cells as the site of that expression. To address this question, the pathway regulating Vegfa expression was reexamined using LE cells rapidly isolated after E2 treatment. In addition, we further characterized the nature of the receptor through which E2 triggers the signaling events that lead to Vegfa expression using the specific ESR1 antagonist ICI 182,780. In agreement with previous results in the whole uterus, E2 stimulated Vegfa mRNA expression in LE cells, peaking at 1 h (4- to 14-fold) and returning to basal levels by 4 h. Treatment with E2 also increased phosphorylation of AKT in LE cells, as well as of the downstream mediators FRAP1 (mTOR), GSK3B, and MDM2. The alpha subunit of HIF1 (HIF1A) was present in LE cells before E2 treatment, was unchanged 1 h after E2, but was >2-fold higher by 4 h. Chromatin immunoprecipitation analysis showed that HIF1A was recruited to the Vegfa promoter by 1 h and was absent again by 4 h. The E2 activation of the PI3K/AKT pathway, HIF1A recruitment to the Vegfa promoter, and Vegfa expression were all blocked by ICI 182,780. In summary, the rapid E2-induced signaling events that lead to the expression of Vegfa observed previously using the whole uterus occur in LE cells and appear to be initiated via a membrane form of ESR1. PMID:19420388
Interplay between the E2F pathway and ?-adrenergic signaling in the pathological hypertrophic response of myocardium.
Major, Jennifer L; Salih, Maysoon; Tuana, Balwant S
The E2F/Pocket protein (Rb) pathway regulates cell growth, differentiation, and death by modulating gene expression. We previously examined this pathway in the myocardium via manipulation of the unique E2F repressor, E2F6, which is believed to repress gene activity independently of Rb. Mice with targeted expression of E2F6 in postnatal myocardium developed dilated cardiomyopathy (DCM) without hypertrophic growth. We assessed the mechanisms of the apparent failure of compensatory hypertrophic growth as well as their response to the ?-adrenergic agonist isoproterenol. As early as 2weeks, E2F6 transgenic (Tg) mice present with dilated thinner left ventricles and significantly reduced ejection fraction and fractional shortening which persists at 6weeks of age, but with no apparent increase in left ventricle weight: body weight (LVW:BW). E2F6-Tg mice treated with isoproterenol (6.1mg/kg/day) show double the increase in LVW:BW than their Wt counterparts (32% vs 16%, p-value: 0.007). Western blot analysis revealed the activation of the adrenergic pathway in Tg heart tissue under basal conditions with ~2-fold increase in the level of ?2-adrenergic receptors (p-value: 8.9E-05), protein kinase A catalytic subunit (PKA-C) (p-value: 0.0176), activated c-Src tyrosine-protein kinase (p-value: 0.0002), extracellular receptor kinase 2 (ERK2) (p-value: 0.0005), and induction of the anti-apoptotic protein Bcl2 (p-value 0. 0.00001). In contrast, a ~60% decrease in the cardiac growth regulator: AKT1 (p-value 0.0001) and a ~four fold increase in cyclic AMP dependent phosphodiesterase 4D (PDE4D), the negative regulator of PKA activity, were evident in the myocardium of E2F6-Tg mice. The expression of E2F3 was down-regulated by E2F6, but was restored by isoproterenol. Further, Rb expression was down-regulated in Tg mice in response to isoproterenol implying a net activation of the E2F pathway. Thus the unique regulation of E2F activity by E2F6 renders the myocardium hypersensitive to adrenergic stimulus resulting in robust hypertrophic growth. These data reveal a novel interplay between the E2F pathway, ?2-adrenergic/PKA/PDE4D, and ERK/c-Src axis in fine tuning the pathological hypertrophic growth response. E2F6 deregulates E2F3 such that pro-hypertrophic growth and survival are enhanced via ?2-adrenergic signaling however this response is outweighed by the induction of anti-hypertrophic signals so that left ventricle dilation proceeds without any increase in muscle mass. PMID:25944088
Analysis of Antigenicity and Topology of E2 Glycoprotein Present on Recombinant Hepatitis C Virus-Like Particles
Clayton, Reginald F.; Owsianka, Ania; Aitken, Jim; Graham, Susan; Bhella, David; Patel, Arvind H.
Purification of hepatitis C virus (HCV) from sera of infected patients has proven elusive, hampering efforts to perform structure-function analysis of the viral components. Recombinant forms of the viral glycoproteins have been used instead for functional studies, but uncertainty exists as to whether they closely mimic the virion proteins. Here, we used HCV virus-like particles (VLPs) generated in insect cells infected with a recombinant baculovirus expressing viral structural proteins. Electron microscopic analysis revealed a population of pleomorphic VLPs that were at least partially enveloped with bilayer membranes and had viral glycoprotein spikes protruding from the surface. Immunogold labeling using specific monoclonal antibodies (MAbs) demonstrated these protrusions to be the E1 and E2 glycoproteins. A panel of anti-E2 MAbs was used to probe the surface topology of E2 on the VLPs and to compare the antigenicity of the VLPs with that of truncated E2 (E2660) or the full-length (FL) E1E2 complex expressed in mammalian cells. While most MAbs bound to all forms of antigen, a number of others showed striking differences in their abilities to recognize the various E2 forms. All MAbs directed against hypervariable region 1 (HVR-1) recognized both native and denatured E2660 with comparable affinities, but most bound either weakly or not at all to the FL E1E2 complex or to VLPs. HVR-1 on VLPs was accessible to these MAbs only after denaturation. Importantly, a subset of MAbs specific for amino acids 464 to 475 and 524 to 535 recognized E2660 but not VLPs or FL E1E2 complex. The antigenic differences between E2660, FL E1E2, and VLPs strongly point to the existence of structural differences, which may have functional relevance. Trypsin treatment of VLPs removed the N-terminal part of E2, resulting in a 42-kDa fragment. In the presence of detergent, this was further reduced to a trypsin-resistant 25-kDa fragment, which could be useful for structural studies. PMID:12097581
Detection of a dense clump in a filament interacting with W51e2
NASA Astrophysics Data System (ADS)
Mookerjea, B.; Vastel, C.; Hassel, G. E.; Gerin, M.; Pety, J.; Goldsmith, P. F.; Black, J. H.; Giesen, T.; Harrison, T.; Persson, C. M.; Stutzki, J.
In the framework of the Herschel/PRISMAS guaranteed time key program, the line of sight to the distant ultracompact H ii region W51e2 has been observed using several selected molecular species. Most of the detected absorption features are not associated with the background high-mass star-forming region and probe the diffuse matter along the line of sight. We present here the detection of an additional narrow absorption feature at ~70 km s-1 in the observed spectra of HDO, NH3 and C3. The 70 km s-1 feature is not uniquely identifiable with the dynamic components (the main cloud and the large-scale foreground filament) so-far identified toward this region. The narrow absorption feature is similar to the one found toward low-mass protostars, which is characteristic of the presence of a cold external envelope. The far-infrared spectroscopic data were combined with existing ground-based observations of 12CO, 13CO, CCH, CN, and C3H2 to characterize the 70 km s-1 component. Using a non-LTE analysis of multiple transitions of NH3 and CN, we estimated the density (n(H2) ~ (1-5) × 105 cm-3) and temperature (10-30 K) for this narrow feature. We used a gas-grain warm-up based chemical model with physical parameters derived from the NH3 data to explain the observed abundances of the different chemical species. We propose that the 70 km s-1 narrow feature arises in a dense and cold clump that probably undergoes collapse to form a low-mass protostar, formed on the trailing side of the high-velocity filament, which is thought to be interacting with the W51 main cloud. While the fortuitous coincidence of the dense clump along the line of sight with the continuum-bright W51e2 compact H ii region has contributed to its nondetection in the continuum images, this same attribute makes it an appropriate source for absorption studies and in particular for ice studies of star-forming regions. Based on data acquired with Herschel and IRAM observatories. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. Warning, no authors found for 2014A&A...566A..55.
E2F7, a novel target, is up-regulated by p53 and mediates DNA damage-dependent transcriptional repression
Carvajal, Luis A.; Hamard, Pierre-Jacques; Tonnessen, Crystal; Manfredi, James J.
The p53 tumor suppressor protein is a transcription factor that exerts its effects on the cell cycle via regulation of gene expression. Although the mechanism of p53-dependent transcriptional activation has been well-studied, the molecular basis for p53-mediated repression has been elusive. The E2F family of transcription factors has been implicated in regulation of cell cycle-related genes, with E2F6, E2F7, and E2F8 playing key roles in repression. In response to cellular DNA damage, E2F7, but not E2F6 or E2F8, is up-regulated in a p53-dependent manner, with p53 being sufficient to increase expression of E2F7. Indeed, p53 occupies the promoter of the E2F7 gene after genotoxic stress, consistent with E2F7 being a novel p53 target. Ablation of E2F7 expression abrogates p53-dependent repression of a subset of its targets, including E2F1 and DHFR, in response to DNA damage. Furthermore, E2F7 occupancy of the E2F1 and DHFR promoters is detected, and expression of E2F7 is sufficient to inhibit cell proliferation. Taken together, these results show that p53-dependent transcriptional up-regulation of its target, E2F7, leads to repression of relevant gene expression. In turn, this E2F7-dependent mechanism contributes to p53-dependent cell cycle arrest in response to DNA damage. PMID:22802528
Regulation of a senescence checkpoint response by the E2F1 transcription factor and p14ARF tumor suppressor
Dimri, Goberdhan P.; Itahana, Koji; Acosta, Meileen; Campisi, Judith
Normal cells do not divide indefinitely due to a process known as replicative senescence. Human cells arrest growth with a senescent phenotype when they acquire one or more critically short telomere as a consequence of cell division. Recent evidence suggests that certain types of DNA damage, chromatin remodeling, or oncogenic forms of Rasor Raf can also elicit a senescence response. We show here that E2F1, a multifunctional transcription factor that binds the retinoblastoma (pRb) tumor suppressor and can either promote or suppress tumorigenesis, induces a senescent phenotype when overexpressed in normal human fibroblasts. Normal human cells stably arrested proliferation and expressed several markers of replicative senescence in response to E2F1. This activity of E2F1 was independent of its pRb binding activity, but dependent on its ability to stimulate gene expression. The E2F1 target gene critical for the senescence response appeared to be the p14ARF tumor suppressor. Replicatively senescent human fibroblasts overexpressed p14ARF, and ectopic expression of p14ARF in presenescent cells induced a phenotype similar to that induced by E2F1. Consistent with a critical role for p14ARF, cells with compromised p53 function were immune to senescence induction by E2F1, as were cells deficient in p14ARF. Our findings support the idea that the senescence response is a critical tumor suppressive mechanism, provide an explanation for the apparently paradoxical roles of E2F1 in oncogenesis, and identify p14ARF as a potentially important mediator of the senescent phenotype.
Dynamical Behaviors of Rb-E2F Pathway Including Negative Feedback Loops Involving miR449
Yan, Fang; Liu, Haihong; Hao, Junjun; Liu, Zengrong
MiRNAs, which are a family of small non-coding RNAs, regulate a broad array of physiological and developmental processes. However, their regulatory roles have remained largely mysterious. E2F is a positive regulator of cell cycle progression and also a potent inducer of apoptosis. Positive feedback loops in the regulation of Rb-E2F pathway are predicted and shown experimentally. Recently, it has been discovered that E2F induce a cluster of miRNAs called miR449. In turn, E2F is inhibited by miR449 through regulating different transcripts, thus forming negative feedback loops in the interaction network. Here, based on the integration of experimental evidence and quantitative data, we studied Rb-E2F pathway coupling the positive feedback loops and negative feedback loops mediated by miR449. Therefore, a mathematical model is constructed based in part on the model proposed in Yao-Lee et al. (2008) and nonlinear dynamical behaviors including the stability and bifurcations of the model are discussed. A comparison is given to reveal the implication of the fundamental differences of Rb-E2F pathway between regulation and deregulation of miR449. Coherent with the experiments it predicts that miR449 plays a critical role in regulating the cell cycle progression and provides a twofold safety mechanism to avoid excessive E2F-induced proliferation by cell cycle arrest and apoptosis. Moreover, numerical simulation and bifurcation analysis shows that the mechanisms of the negative regulation of miR449 to three different transcripts are quite distinctive which needs to be verified experimentally. This study may help us to analyze the whole cell cycle process mediated by other miRNAs more easily. A better knowledge of the dynamical behaviors of miRNAs mediated networks is also of interest for bio-engineering and artificial control. PMID:23028477
Osteoinductivity of demineralized bone matrix in immunocompromised mice and rats is decreased by ovariectomy and restored by estrogen replacement.
McMillan, J; Kinney, R C; Ranly, D M; Fatehi-Sedeh, S; Schwartz, Z; Boyan, B D
The osteoinduction potential of human demineralized bone matrix (DBM) in females with low estrogen (E2) is unknown. Moreover, the osteoinductivity of commercial human DBM is tested in male athymic rats and mice, but DBM performance in these animals may not reflect performance in female animals or provide information on E2's role in the process. To gain insight, human DBM was implanted bilaterally in the gastrocnemius of twenty-four athymic female mice (10 mg/implant) and twenty-four athymic female rats (15 mg/implant). Eight animals in each group were sham-operated (SHAM), ovariectomized (OVX), or ovariectomized with E2-replacement (OVX+E2) via subcutaneous slow release capsules of 17beta-estradiol. OVX and OVX+E2 animals were pair-fed to SHAM animals. Four animals from each group were euthanized at 35 days and four at 56 days. Animal weight, uterine weight, and blood estrogen levels confirmed that pair feeding, ovariectomy, and E2 replacement were successful. Histological sections of implanted tissues were evaluated qualitatively for absence or presence of DBM, ossicle formation, and new bone or cartilage using a previously developed qualitative scoring system (QS) and by histomorphometry to obtain a quantitative assessment of osteoinduction. OVX mice had a small but significant QS decrease at 35 days compared to SHAM mice, confirmed by quantitative measurement of ossicle, marrow space, and new bone areas. The QS in rats was not affected by OVX but histomorphometry showed decreased new bone in OVX rats, which was restored by E2. The QS indicated that the number of new bone sites was not reduced by OVX in rats or mice at 56 days, but the relative amount of new bone v. marrow space was affected and differed with animal species. Residual DBM was less in OVX animals, indicating that DBM resorption was affected. Cartilage was present in rats but not in mice, suggesting that endochondral ossification was slower and indicating that bone graft studies in these species are not necessarily comparable. These results show the importance of E2 in human DBM-induced bone formation and suggest that E2 may be needed for clinical effectiveness in post-menopausal women. PMID:16973427
Investigation of the E2 and E3 matrix elements in 200Hg using inelastic scattering
NASA Astrophysics Data System (ADS)
Rand, Evan; Bildstein, Vinzenz; Garrett, Paul; Hadinia, Baharak; Jamieson, Drew; Jigmeddorj, Badamsambuu; Leach, Kyle; Svensson, Carl; Ball, Gordon; Faestermann, Thomas; Hertenberger, Ralf; Wirth, Hans-Friedrich
A nuclear structure campaign has been initiated investigating the isotopes of mercury near A = 199. Currently 199Hg provides the most stringent limit on an atomic electric dipole moment (EDM). Theoretical calculations for 199Hg are very difficult and give varied predictions for the excited-state spectrum. Understanding the E2 and E3 strengths in the neighbouring even-even isotopes of mercury will make it possible to develop a nuclear structure model for the Schiff strength based on these matrix elements, and thereby constrain present model predictions of the contribution of octupole collectivity to the Schiff moment of the nucleus. The work presented here comprises two experiments using a 22 MeV deuterium beam impinging on an isotopically enriched target of 200Hg32S. The first experiment is an inelastic deuteron scattering experiment, which consists of 20 angles ranging from 10 to 115 degrees. The second experiment is a neutron-pickup reaction into 199Hg, and includes 10 angles from 5 to 50 degrees. These experiments were performed using the Q3D spectrograph at the Maier-Leibnitz Laboratory (MLL) in Garching, Germany. Preliminary results from these experiments will be presented.
Overexpressed TRPV3 ion channels in skin keratinocytes modulate pain sensitivity via prostaglandin E2
Huang, Susan M.; Lee, Hyosang; Chung, Man-Kyo; Park, Una; Yu, Yin Yin; Bradshaw, Heather B.; Coulombe, Pierre A.; Walker, J. Michael; Caterina, Michael J.
The ability to sense changes in the environment is essential for survival because it permits responses such as withdrawal from noxious stimuli and regulation of body temperature. Keratinocytes, which occupy much of the skin epidermis, are situated at the interface between the external environment and the body's internal milieu, and have long been appreciated for their barrier function against external insults. The recent discovery of temperature-sensitive TRPV ion channels in keratinocytes has raised the possibility that these cells also actively participate in acute temperature and pain sensation. To address this notion, we generated and characterized transgenic mice that overexpress TRPV3 in epidermal keratinocytes under the control of the keratin 14 promoter. Compared to wild-type controls, keratinocytes overexpressing TRPV3 exhibited larger currents as well as augmented prostaglandin E2 (PGE2) release in response to two TRPV3 agonists, 2-aminoethoxydiphenyl borate (2APB) and heat. Thermal selection behavior and heat-evoked withdrawal behavior of naďve mice overexpressing TRPV3 were not consistently altered. Upon selective pharmacological inhibition of TRPV1 with JNJ-7203212, however, the keratinocyte-specific TRPV3 transgenic mice showed increased escape responses to noxious heat relative to their wild-type littermates. Co-administration of the cyclooxygenase inhibitor, ibuprofen, with the TRPV1 antagonist decreased inflammatory thermal hyperalgesia in transgenic but not wild-type animals. Our results reveal a previously undescribed mechanism for keratinocyte participation in thermal pain transduction through keratinocyte TRPV3 ion channels and the intercellular messenger PGE2. PMID:19091963
Crystal structure of (E)-2-hydroxy-4?-methoxyazastilbene
Chantrapromma, Suchada; Kaewmanee, Narissara; Boonnak, Nawong; Chantrapromma, Kan; Ghabbour, Hazem A.; Fun, Hoong-Kun
The title azastilbene derivative, C14H13NO2 {systematic name: (E)-2-[(4-methoxybenzylidene)amino]phenol}, is a product of the condensation reaction between 4-methoxybenzaldehyde and 2-aminophenol. The molecule adopts an E conformation with respect to the azomethine C=N bond and is almost planar, the dihedral angle between the two substituted benzene rings being 3.29?(4)°. The methoxy group is coplanar with the benzene ring to which it is attached, the Cmethyl—O—C—C torsion angle being ?1.14?(12)°. There is an intramolecular O—H?N hydrogen bond generating an S(5) ring motif. In the crystal, molecules are linked via C—H?O hydrogen bonds, forming zigzag chains along [10-1]. The chains are linked via C—H?? interactions, forming a three-dimensional structure.
Seniority, collectivity, and B(E 2) enhancement in 72Ni
NASA Astrophysics Data System (ADS)
Chiara, C. J.; Stefanescu, I.; Walters, W. B.; Sharp, N.; Alcorta, M.; Carpenter, M. P.; Gürdal, G.; Hoffman, C. R.; Janssens, R. V. F.; Kay, B. P.; Kondev, F. G.; Lauritsen, T.; Lister, C. J.; McCutchan, E. A.; Rogers, A. M.; Seweryniak, D.; Zhu, S.; Fornal, B.; Królas, W.; Paw?at, T.; Wrzesi?ski, J.
Gamma rays assigned to 2872Ni44have been identified with Gammasphere in deep-inelastic reactions involving a 450-MeV 76Ge beam and a 198Pt target. Using a combination of spectra produced by double gates on the known 454-, 843-, and 1095-keV members of the ground-state cascade, a coincident line at 199 keV has been identified and is tentatively assigned as the 8+ -->6+ transition. These ?-ray coincidences were observed only in prompt events, indicating an 8+ half-life below 20 ns and requiring a large B(E 2) enhancement compared to that expected from a seniority scheme. This value is consistent with models showing decay to a seniority ? = 4 , 6+ level that is depressed by the same two-body interaction responsible for the rather low 1095-keV 21+ energy, as compared to the valence-symmetry counterpart
Cryo-mechanical tests of Ames 24E2 IR-black coating
NASA Technical Reports Server (NTRS)
Smith, Sheldon M.
In addition to the ambient condition tape test, five mechanical tests of the IR-black coating, Ames 24E2, were performed at either liquid helium or liquid nitrogen temperatures. Tensile strain in the coating at liquid nitrogen temperature was measured up to values of 4E-3, both before and after the coating was cycled down to liquid helium temperature. When applied to an aluminum substrate which was then bent in liquid nitrogen, the aluminum substrate always failed (permanently deformed) well before the coating failed. Sinusoidal accelerations up to 45 Gs in liquid nitrogen and 25 Gs in liquid helium did not crack or otherwise visibly damage the coating. Both sinusoidal and random acceleration at about 90 K of a representative baffle vane structure, at frequencies from 10 to 2000 Hz and up to 15 Gs, did not damage the coating, even at the intersection of a baffle with the telescope tube. Thus on a macroscopic level, cryogenic cooling and various levels of acceleration and strain did not affect this coating. However, on a microscopic scale, some loose particles were found associated with several tests. Outgassing data are also given.
Phenothiazine is a potent inhibitor of prostaglandin E2 production by Candida albicans biofilms.
Ells, Ruan; Kemp, Gabré; Albertyn, Jacobus; Kock, Johan L F; Pohl, Carolina H
Candida albicans is an important opportunistic yeast pathogen of humans and has the ability to form drug-resistant biofilms, with increased expression of multidrug ATP-binding cassette (ABC) transporters. These biofilms are also capable of secreting immune-modulating prostaglandin E2 (PGE2 ) from host-derived arachidonic acid (AA). Phenothiazine, an aromatic amine, and its derivatives display broad activity as inhibitors and antioxidants. These compounds have fungistatic and fungicidal activity against planktonic C. albicans and can inhibit ABC transporters of C. albicans. This study investigated the effect of phenothiazine on biofilm formation, ABC transporters and PGE2 production by C. albicans. This was carried out by growing C. albicans biofilms in the presence of AA and phenothiazine and measuring the biomass as well as reduction of 2,3-bis(2-methoxy-4-nitro-5-sulphophenyl)-5[(phenylamino) carbonyl]-2H tetrazolium hydroxide. The effect on ABC transporters was determined by rhodamine 6G efflux, and the concentration of PGE2 was determined by a monoclonal PGE2 enzyme-linked immunosorbent assay and LC/MS/MS. Our results indicate that phenothiazine can cause a reduction in both the metabolic activity and biomass of C. albicans biofilms, without affecting biofilm morphology or ABC transporters. However, it is a potent inhibitor of PGE2 production by C. albicans biofilms. PMID:24103090
Ibuprofen bioconcentration and prostaglandin E2 levels in the bluntnose minnow Pimephales notatus.
Bhandari, Khageshor; Venables, Barney
Prostanoids are oxygenated derivatives of arachidonic acid with a wide range of physiological effects in vertebrates including modulation of inflammation and innate immune responses. Nonsteroidal anti-inflammatory drugs (NSAIDs) act through inhibition of cyclooxygenase (COX) conversion of arachidonic acid to prostanoids. In order to better understand the potential of environmental NSAIDS for interruption of normal levels of COX products in fishes, we developed an LC/MS/MS-based approach for tissue analysis of 7 prostanoids. Initial studies examining muscle, gut and gill demonstrated that prostaglandin E2 (PGE2) was the most abundant of the measured prostanoids in all tissues and that gill tissue had the highest and most consistent concentrations of PGE2. After short-term 48-h laboratory exposures to nominal concentrations of 5, 25, 50 and 100?g/L ibuprofen, 50?g/L and 100?g/L exposure concentrations resulted in significant reduction of gill tissue PGE2 concentration by approximately 30% and 80% respectively. The lower exposures did not result in significant reductions when compared to unexposed controls. Measured tissue concentrations of ibuprofen indicated that this NSAID had little potential for bioconcentration (BCF=1.3) and the IC(50) of ibuprofen for inhibition of PGE2 production in gill tissue was estimated to be 0.4?M. PMID:21111061
Improved red sensitivity deep depletion e2v devices for the Gemini North GMOS instrument
NASA Astrophysics Data System (ADS)
Roth, Katherine C.; Kleinman, Scot J.; Chiboucas, Kristin; Schiavon, Ricardo; Hanna, Kevin; Rippa, Mathew; White, John K.; Walls, Brian; Yamasaki, Chris; Murowinski, Richard; Labrie, Kathleen; Gimeno, German; Simpson, Mark
The GMOS-N instrument was upgraded with new CCDs in October 2011, improving the instrument sensitivity at both red and blue wavelengths. The deep depletion devices are manufactured by e2v (42-90 with multi-layer 3 coating) and extend the useful wavelength range of GMOS-N to 0.98 microns (compared to 0.94 microns previously). These detectors also exhibit much lower fringing than the original EEV detectors that had been in use since GMOS-N was commissioned in 2002. All other characteristics of the new detectors (readout speed, pixel size and format, detector controller, noise, gain) are similar to the original CCDs. Operating the new detectors in all amps mode (2 per CCD) has effectively improved the readout speed by a factor of 2. The new devices were selected to provide a quick and relatively simply upgrade route while technical issues with the Hamamatsu devices, originally planned for the upgrade, were investigated and resolved. We discuss the rationale for this interim upgrade, the upgrade process and attending issues. The new detectors have been used for science since November 2011. We present commissioning results illustrating the resulting gain in sensitivity over the original detector package. Gemini is still committed to installing Hamamatsu devices, which will further extend the useful wavelength range of GMOS to 1.03 microns, in both North and South GMOS instruments. We discuss the status of the Hamamatsu project and the current planned schedule for these future upgrades.
Crystal structure of (E)-2-hy-droxy-4'-meth-oxy-aza-stilbene.
Chantrapromma, Suchada; Kaewmanee, Narissara; Boonnak, Nawong; Chantrapromma, Kan; Ghabbour, Hazem A; Fun, Hoong-Kun
The title aza-stilbene derivative, C14H13NO2 {systematic name: (E)-2-[(4-meth-oxy-benzyl-idene)amino]-phenol}, is a product of the condensation reaction between 4-meth-oxy-benzaldehyde and 2-amino-phenol. The mol-ecule adopts an E conformation with respect to the azomethine C=N bond and is almost planar, the dihedral angle between the two substituted benzene rings being 3.29?(4)°. The meth-oxy group is coplanar with the benzene ring to which it is attached, the Cmeth-yl-O-C-C torsion angle being -1.14?(12)°. There is an intra-molecular O-H?N hydrogen bond generating an S(5) ring motif. In the crystal, mol-ecules are linked via C-H?O hydrogen bonds, forming zigzag chains along [10-1]. The chains are linked via C-H?? inter-actions, forming a three-dimensional structure. PMID:26090124
Prostaglandin E2 and muscle proteolysis: effect of burn injury and cycloheximide.
McKinley, C J; Turinsky, J
Rats were subjected to a single hindlimb scald, and 3 days later soleus muscles from the burned and contralateral unburned hindlimbs were studied in vitro. Burned limb muscle released 354% more prostaglandin E2 (PGE2) and 119% more tyrosine than the contralateral uninjured counterpart. Neither the rate of net proteolysis in the uninjured muscle nor the stimulated net proteolysis in the burned limb muscle could be reduced by 90% inhibition of PGE2 production with aspirin or indomethacin. Inhibition of tissue protein synthesis with 5 X 10(-5) M cycloheximide stimulated tyrosine release by soleus muscles of both hindlimbs, but the increment in the burned limb muscle was 167% greater than in the contralateral uninjured counterpart. Concomitantly, cycloheximide decreased PGE2 releases by injured and uninjured muscles 90 and 73%, respectively. This previously unrecognized action of cycloheximide was investigated in soleus muscles of normal uninjured rats. It was found that 1 X 10(-6) M cycloheximide produces a 70% inhibition of muscle PGE2 release and increasing the concentration of inhibitor up to 500-fold does not further decrease PGE2 production. Cycloheximide acts by reducing the availability of endogenous arachidonic acid for PGE2 synthesis. PMID:3080903
Lateral Load Testing of the Advanced Stirling Convertor (ASC-E2) Heater Head
NASA Technical Reports Server (NTRS)
Cornell, Peggy A.; Krause, David L.; Davis, Glen; Robbie, Malcolm G.; Gubics, David A.
Free-piston Stirling convertors are fundamental to the development of NASA s next generation of radioisotope power system, the Advanced Stirling Radioisotope Generator (ASRG). The ASRG will use General Purpose Heat Source (GPHS) modules as the energy source and Advanced Stirling Convertors (ASCs) to convert heat into electrical energy, and is being developed by Lockheed Martin under contract to the Department of Energy. Achieving flight status mandates that the ASCs satisfy design as well as flight requirements to ensure reliable operation during launch. To meet these launch requirements, GRC performed a series of quasi-static mechanical tests simulating the pressure, thermal, and external loading conditions that will be experienced by an ASC-E2 heater head assembly. These mechanical tests were collectively referred to as "lateral load tests" since a primary external load lateral to the heater head longitudinal axis was applied in combination with the other loading conditions. The heater head was subjected to the operational pressure, axial mounting force, thermal conditions, and axial and lateral launch vehicle acceleration loadings. To permit reliable prediction of the heater head s structural performance, GRC completed Finite Element Analysis (FEA) computer modeling for the stress, strain, and deformation that will result during launch. The heater head lateral load test directly supported evaluation of the analysis and validation of the design to meet launch requirements. This paper provides an overview of each element within the test and presents assessment of the modeling as well as experimental results of this task.
Prostaglandin E2 promotes MYCN non-amplified neuroblastoma cell survival via ?-catenin stabilization
Jansen, Sepp R; Holman, Rian; Hedemann, Ilja; Frankes, Ewoud; Elzinga, Carolina R S; Timens, Wim; Gosens, Reinoud; de Bont, Eveline S; Schmidt, Martina
Amplification of MYCN is the most well-known prognostic marker of neuroblastoma risk classification, but still is only observed in 25% of cases. Recent evidence points to the cyclic adenosine monophosphate (cAMP) elevating ligand prostaglandin E2 (PGE2) and ?-catenin as two novel players in neuroblastoma. Here, we aimed to define the potential role of PGE2 and cAMP and its potential interplay with ?-catenin, both of which may converge on neuroblastoma cell behaviour. Gain and loss of ?-catenin function, PGE2, the adenylyl cyclase activator forskolin and pharmacological inhibition of cyclooxygenase-2 (COX-2) were studied in two human neuroblastoma cell lines without MYCN amplification. Our findings show that PGE2 enhanced cell viability through the EP4 receptor and cAMP elevation, whereas COX-2 inhibitors attenuated cell viability. Interestingly, PGE2 and forskolin promoted glycogen synthase kinase 3? inhibition, ?-catenin phosphorylation at the protein kinase A target residue ser675, ?-catenin nuclear translocation and TCF-dependent gene transcription. Ectopic expression of a degradation-resistant ?-catenin mutant enhances neuroblastoma cell viability and inhibition of ?-catenin with XAV939 prevented PGE2-induced cell viability. Finally, we show increased ?-catenin expression in human high-risk neuroblastoma tissue without MYCN amplification. Our data indicate that PGE2 enhances neuroblastoma cell viability, a process which may involve cAMP-mediated ?-catenin stabilization, and suggest that this pathway is of relevance to high-risk neuroblastoma without MYCN amplification. PMID:25266063
Suppression of Alzheimer-associated inflammation by microglial prostaglandin-E2 EP4 receptor signaling.
Woodling, Nathaniel S; Wang, Qian; Priyam, Prachi G; Larkin, Paul; Shi, Ju; Johansson, Jenny U; Zagol-Ikapitte, Irene; Boutaud, Olivier; Andreasson, Katrin I
A persistent and nonresolving inflammatory response to accumulating A? peptide species is a cardinal feature in the development of Alzheimer's disease (AD). In response to accumulating A? peptide species, microglia, the innate immune cells of the brain, generate a toxic inflammatory response that accelerates synaptic and neuronal injury. Many proinflammatory signaling pathways are linked to progression of neurodegeneration. However, endogenous anti-inflammatory pathways capable of suppressing A?-induced inflammation represent a relatively unexplored area. Here we report that signaling through the prostaglandin-E2 (PGE2) EP4 receptor potently suppresses microglial inflammatory responses to A?42 peptides. In cultured microglial cells, EP4 stimulation attenuated levels of A?42-induced inflammatory factors and potentiated phagocytosis of A?42. Microarray analysis demonstrated that EP4 stimulation broadly opposed A?42-driven gene expression changes in microglia, with enrichment for targets of IRF1, IRF7, and NF-?B transcription factors. In vivo, conditional deletion of microglial EP4 in APPSwe-PS1?E9 (APP-PS1) mice conversely increased inflammatory gene expression, oxidative protein modification, and A? deposition in brain at early stages of pathology, but not at later stages, suggesting an early anti-inflammatory function of microglial EP4 signaling in the APP-PS1 model. Finally, EP4 receptor levels decreased significantly in human cortex with progression from normal to AD states, suggesting that early loss of this beneficial signaling system in preclinical AD development may contribute to subsequent progression of pathology. PMID:24760848
Prostaglandin E2 Regulates Liver versus Pancreas Cell Fate Decisions and Endodermal Outgrowth
Nissim, Sahar; Sherwood, Richard I.; Wucherpfennig, Julia; Saunders, Diane; Harris, James M.; Esain, Virginie; Carroll, Kelli J.; Frechette, Gregory M.; Kim, Andrew J.; Hwang, Katie L.; Cutting, Claire C.; Elledge, Susanna; North, Trista E.; Goessling, Wolfram
SUMMARY The liver and pancreas arise from common endodermal progenitors. How these distinct cell fates are specified is poorly understood. Here, we describe prostaglandin E2 (PGE2) as a regulator of endodermal fate specification during development. Modulating PGE2 activity has opposing effects on liver-versus-pancreas specification in zebrafish embryos as well as mouse endodermal progenitors. The PGE2 synthetic enzyme cox2a and receptor ep2a are patterned such that cells closest to PGE2 synthesis acquire a liver fate whereas more distant cells acquire a pancreas fate. PGE2 interacts with the bmp2b pathway to regulate fate specification. At later stages of development, PGE2 acting via the ep4a receptor promotes outgrowth of both the liver and pancreas. PGE2 remains important for adult organ growth, as it modulates liver regeneration. This work provides in vivo evidence that PGE2 may act as a morphogen to regulate cell fate decisions and outgrowth of the embryonic endodermal anlagen. PMID:24530296
Urinary Prostaglandin E2 Metabolite and Pancreatic Cancer Risk: Case-Control Study in Urban Shanghai
Zhao, Jing; Wang, Jing; Du, Jinfeng; Xu, Hongli; Zhang, Wei; Ni, Quan-Xing; Yu, Herbert; Risch, Harvey A.; Gao, Yu-Tang; Gao, Ying
Pancreatic cancer has been increasing in importance in Shanghai over the last four decades. The etiology of the disease is still unclear. Evidence suggests that the COX-2 pathway, an important component of inflammation, may be involved in the disease. We aimed to evaluate the association between urinary prostaglandin E2 metabolite (PGE-M) level and risk of pancreatic cancer. From a recent population-based case-control study in Shanghai, 200 pancreatic ductal adenocarcinoma cases and 200 gender- and age- frequency matched controls were selected for the present analysis. Urinary PGE-M was measured with a liquid chromatography/mass spectrometric assay. Adjusted unconditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). A positive association was observed between PGE-M leve and pancreatic cancer risk: OR = 1.63 (95% CI 1.01–2.63) for the third tertile compared to the first. Though the interactions were not statistically significant, the associations tended to be stronger among subjects with diabetes history (OR = 3.32; 95% CI 1.20–9.19) and higher meat intake (OR = 2.12; 95% CI 1.10–4.06). The result suggests that higher urinary PGE-M level may be associated with increased risk of pancreatic ductal adenocarcinoma. PMID:25679523
Up-regulation of nuclear factor E2-related factor 2 upon SVCV infection.
Yang, Yi; Huang, Jian; Li, Lijuan; Lin, Li; Zhai, Yanhua; Chen, Xiaoxuan; Liu, Xueqin; Wu, Zhixin; Yuan, Junfa
Nuclear factor E2 - related factor 2 (Nrf2) is a crucial transcription factor that regulates the basal and inducible expression of many antioxidant response element (ARE)-dependent genes, including heme oxygenase-1 (HO-1) and superoxide dismutase 1 (SOD1). The Nrf2/ARE pathway has been regarded as a critical switch in the initiation of cellular defence systems for surviving oxidative insults and viral infection. In this study, the Nrf2 gene of EPC cells, which is originally derived from Pimephales promelas, was cloned, and an investigation on the interactions between Nrf2 and spring viraemia of carp virus (SVCV) was performed. These results demonstrated that the virus facilitated the nuclear accumulation of Nrf2 and up-regulated its transcriptional and protein profiles in EPC cells. In addition, exogenous activation of Nrf2 conferred EPC cells with a higher cellular total antioxidant capacity via an increase in the expression of HO-1 and SOD1, but did not suppress the replication of SVCV. PMID:25038284
Inhibition of prostaglandin E2 production by flavone and its related compounds.
Kaneko, Tadayoshi; Chiba, Hiroshige; Horie, Norio; Kato, Takao; Kobayashi, Masaki; Hashimoto, Ken; Kusama, Kaoru; Sakagami, Hiroshi
We have previously reported that among 12 major ingredients of Sairei-to, Scutellariae radix inhibited prostaglandin E(2) (PGE(2)) production by lipopolysaccharide (LPS)-activated mouse macrophage-like RAW264.7 cells more efficiently than other ingredients, and wogonin, a major flavonoid from Scutellariae radix, showed greater inhibitory activity and membrane permeability than baicalein and baicalin. Here the effects of six other flavonoids, with similar structures, on membrane permeability and PGE(2) production were investigated. 7-Methoxyflavone inhibited the LPS-stimulated PGE(2) production to the greatest extent, followed by flavone>wogonin (5,7-dihydroxy-8-methoxyflavone)> 7,8-dimethoxyflavone>chrysin (5,7-dihydroxyflavone)> baicalein (5,6,7-trihydroxyflavone)>chromone. 7-Methoxyflavone also showed the highest membrane permeability, followed by flavone>chrysin>7,8-dimethoxy-flavone>wogonin>baicalein. When PGE(2) inhibitory activity was expressed per molecule incorporated into the cells, wogonin produced the greatest inhibition, further substantiating its anti-inflammatory potency. PMID:20133976
Highly charged ions with E1, M1, and E2 transitions within laser range
NASA Astrophysics Data System (ADS)
Berengut, J. C.; Dzuba, V. A.; Flambaum, V. V.; Ong, A.
Level crossings in the ground state of ions occur when the nuclear charge Z and ion charge Zion are varied along an isoelectronic sequence until the two outermost shells are nearly degenerate. We examine all available level crossings in the periodic table for both near-neutral ions and highly charged ions (HCIs). Normal E1 transitions in HCIs are in x-ray range; however, level crossings allow for optical electromagnetic transitions that could form the reference transition for high-accuracy atomic clocks. Optical E1 (due to configuration mixing), M1, and E2 transitions are available in HCIs near level crossings. We present scaling laws for energies and amplitudes that allow us to make simple estimates of systematic effects of relevance to atomic clocks. HCI clocks could have some advantages over existing optical clocks because certain systematic effects are reduced; for example, they can have much smaller thermal shifts. Other effects such as fine-structure and hyperfine splitting are much larger in HCIs, which can allow for richer spectra. HCIs are excellent candidates for probing variations in the fine-structure constant ? in atomic systems as there are transitions with the highest sensitivity to ? variation.
A preliminary result of self-calibration bundle adjustment of Chang'E-2 stereo imagery
NASA Astrophysics Data System (ADS)
Liu, Yiliang; Liu, Bin; Peng, Man; Di, Kaichang
The high resolution lunar global images acquired by Chang'E-2 (CE-2) CCD camera orbiter are of great importance for lunar science research as well as preparation of the landing and surface operation of Chang'E-3 (CE-3) lunar rover. In this paper, a rigorous geometric model of CE-2 CCD camera is developed based on the push-broom imaging principle. A self-calibration bundle adjustment (SCBA) method is proposed to eliminate the inconsistencies between forward- and backward-looking images, which are caused by the inaccuracy of exterior orientation (EO) parameters and the uncertain relationship between the two CCD line arrays of the camera. The interior orientation (IO) model is refined by adding several additional parameters and the EO parameters are fitted by a third-order polynomial model. Strategies for ensuring the robustness and reliability of the solution are also adopted, including EO pseudo observations selection, reasonable weight determination, and truncated singular value decomposition method. After adjustment, the inconsistencies between the forward- and backward-looking images are eliminated effectively by reducing the image-space residuals from around 20 pixels to sub-pixel. Based on the adjustment, high precision DEM (Digital Elevation Model) and DOM (Digital Ortho Map) of a local area at Sinus Iridum (pre-selected CE-3 landing site) are generated automatically.
Suppression of Alzheimer-Associated Inflammation by Microglial Prostaglandin-E2 EP4 Receptor Signaling
Woodling, Nathaniel S.; Wang, Qian; Priyam, Prachi G.; Larkin, Paul; Shi, Ju; Johansson, Jenny U.; Zagol-Ikapitte, Irene; Boutaud, Olivier
A persistent and nonresolving inflammatory response to accumulating A? peptide species is a cardinal feature in the development of Alzheimer's disease (AD). In response to accumulating A? peptide species, microglia, the innate immune cells of the brain, generate a toxic inflammatory response that accelerates synaptic and neuronal injury. Many proinflammatory signaling pathways are linked to progression of neurodegeneration. However, endogenous anti-inflammatory pathways capable of suppressing A?-induced inflammation represent a relatively unexplored area. Here we report that signaling through the prostaglandin-E2 (PGE2) EP4 receptor potently suppresses microglial inflammatory responses to A?42 peptides. In cultured microglial cells, EP4 stimulation attenuated levels of A?42-induced inflammatory factors and potentiated phagocytosis of A?42. Microarray analysis demonstrated that EP4 stimulation broadly opposed A?42-driven gene expression changes in microglia, with enrichment for targets of IRF1, IRF7, and NF-?B transcription factors. In vivo, conditional deletion of microglial EP4 in APPSwe-PS1?E9 (APP-PS1) mice conversely increased inflammatory gene expression, oxidative protein modification, and A? deposition in brain at early stages of pathology, but not at later stages, suggesting an early anti-inflammatory function of microglial EP4 signaling in the APP-PS1 model. Finally, EP4 receptor levels decreased significantly in human cortex with progression from normal to AD states, suggesting that early loss of this beneficial signaling system in preclinical AD development may contribute to subsequent progression of pathology. PMID:24760848
Gliotransmission by Prostaglandin E2: A Prerequisite for GnRH Neuronal Function?
Clasadonte, Jerome; Sharif, Ariane; Baroncini, Marc; Prevot, Vincent
Over the past four decades it has become clear that prostaglandin E2 (PGE2), a phospholipid-derived signaling molecule, plays a fundamental role in modulating the gonadotropin-releasing hormone (GnRH) neuroendocrine system and in shaping the hypothalamus. In this review, after a brief historical overview, we highlight studies revealing that PGE2 released by glial cells such as astrocytes and tanycytes is intimately involved in the active control of GnRH neuronal activity and neurosecretion. Recent evidence suggests that hypothalamic astrocytes surrounding GnRH neuronal cell bodies may respond to neuronal activity with an activation of the erbB receptor tyrosine kinase signaling, triggering the release of PGE2 as a chemical transmitter from the glia themselves, and, in turn, leading to the feedback regulation of GnRH neuronal activity. At the GnRH neurohemal junction, in the median eminence of the hypothalamus, PGE2 is released by tanycytes in response to cell–cell signaling initiated by glial cells and vascular endothelial cells. Upon its release, PGE2 causes the retraction of the tanycyte end-feet enwrapping the GnRH nerve terminals, enabling them to approach the adjacent pericapillary space and thus likely facilitating neurohormone diffusion from these nerve terminals into the pituitary portal blood. In view of these new insights, we suggest that synaptically associated astrocytes and perijunctional tanycytes are integral modulatory elements of GnRH neuronal function at the cell soma/dendrite and nerve terminal levels, respectively. PMID:22649391
Role of carbonic anhydrase in bone resorption induced by prostaglandin E2 in vitro
NASA Technical Reports Server (NTRS)
Hall, G. E.; Kenny, A. D.
The possible role of carbonic anhydrase in bone resorption induced by prostaglandin E2 (PGE2) was studied using an in vitro neonatal mouse calvarial culture system. PGE2 (10 to the -6th M) was effective in stimulating resorption, as assessed by calcium release into culture media. This enhanced resorption was accompanied by significant increases in calvarial carbonic anhydrase activity over control values at 48 and 96 h. At 48 h, bones treated with PGE2 had 20 percent more carbonic anhydrase activity than controls. By 96 h, treated bones contained 79 percent more carbonic anhydrase activity than controls. PGE2-induced bone resorption was inhibited by the carbonic anhydrase inhibitor acetazolamide in a dose-dependent fashion from 10 to the -5th to 10 to the -4th M with 77 percent inhibition observed at 10 to the -4th M. The acetazolamide analogue CL 13,850 (N-t-butylacetazolamide), which does not inhibit carbonic anhydrase, failed to inhibit PGE2-induced resorption. These results are consistent with the hypothesis that carbonic anhydrase is a necessary component of the osteoclastic bone resorptive mechanism.
Crosstalk between E2F3 and p19ARF/p53 in the regulation of cell cycle progression and tumorigenesis
Aslanian, Aaron Spencer
E2F activity was originally identified as a critical component of the cellular machinery responsible for promoting cell cycle progression that is co-opted during transformation and tumorigenesis. Classic E2F target genes ...
Isolation, characterization, and mapping of gene encoding dihydrolipoyl succinyltransferase (E2k) of human [alpha]-ketoglutarate dehydrogenase complex
Ali, G.; Cai, Xingang; Sheu, Kwan-Fu R.; Blass, J.P. (Cornell Univ. Medical College, White Plains, NY (United States)); Wasco, W.; Gaston, S.M.; Tanzi, R.E.; Cooper, A.J.L.; Gusella, J.F. (Massachusetts General Hospital, Charleston, MA (United States)); Szabo, P. (Cornell Univ. Medical College, New York, NY (United States))
The authors have isolated and sequenced cDNAs representing the full-length (2987-bp) gene for dihydrolipoyl succinyltransferase (E2k component) of the human [alpha]-ketoglutarate dehydrogenase complex (KHDHC) from a human fetal brain cDNA library. The E2k cDNA was mapped to human chromosome 14 using a somatic cell hybrid panel, and more precisely to band 14q24.3 by in situ hybridization. This cDNA also cross-hybridized to an apparent E2k pseudogene on chromosome 1p31. Northern analysis revealed the E2k gene to be ubiquitously expressed in peripheral tissues and brain. Interestingly, chromosome 14q24.3 has recently been reported to contain gene defects for an early-onset form of familial Alzheimer's disease and for Machado-Joseph disease. Future studies will be necessary to determine whether the E2K gene plays a role in either of these two disorders.
HCV E2 may induce apoptosis of Huh-7 cells via a mitochondrial-related caspase pathway
Chiou, H.-L. [School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China) and Department of Clinical Laboratory, Chung Shan Medical University Hospital, Taichung, Taiwan (China)]. E-mail: email@example.com; Hsieh, Y.-S. [Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Hsieh, M.-R. [Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Chen, T.-Y. [Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan (China); Department of Internal Medicine, Chung Shan Medical University Hospital, Taichung, Taiwan (China)
Introduction: One unusual characteristic of HCV is to establish chronic infection and the precise mechanisms remain unclear. Materials and methods: Huh-7 cells were transiently transfected with E2 and subjected to MTT assay, DNA fragmentation assay, and Western blotting to see the impact of E2 protein on apoptosis. Results and discussion: E2 may inhibit cell proliferation by inducing apoptosis and pro-caspases 3, 8, and 9 were cleaved and activated to result in the presence of active forms in a time-dependent fashion, which suggest that E2-induced apoptosis is caspase-dependent. Furthermore, the cytosolic level of cytochrome c was increased together with a gradually down-regulated Bcl-2 and up-regulated Bax protein expression. The continuing reduction of Bid protein and the gradual increase of tBid protein also indicated that a time-dependent increased turn-over of Bid protein into tBid. Taken together, our data suggested that HCV E2 may induce apoptosis through a mitochondrial damage-mediated caspase pathway.
Extensive amplification of the E2F transcription factor binding sites by transposons during evolution of Brassica species.
Hénaff, Elizabeth; Vives, Cristina; Desvoyes, Bénédicte; Chaurasia, Ankita; Payet, Jordi; Gutierrez, Crisanto; Casacuberta, Josep M
Transposable elements (TEs) are major players in genome evolution. The effects of their movement vary from gene knockouts to more subtle effects such as changes in gene expression. It has recently been shown that TEs may contain transcription factor binding sites (TFBSs), and it has been proposed that they may rewire new genes into existing transcriptional networks. However, little is known about the dynamics of this process and its effect on transcription factor binding. Here we show that TEs have extensively amplified the number of sequences that match the E2F TFBS during Brassica speciation, and, as a result, as many as 85% of the sequences that fit the E2F TFBS consensus are within TEs in some Brassica species. We show that these sequences found within TEs bind E2Fa in vivo, which indicates a direct effect of these TEs on E2F-mediated gene regulation. Our results suggest that the TEs located close to genes may directly participate in gene promoters, whereas those located far from genes may have an indirect effect by diluting the effective amount of E2F protein able to bind to its cognate promoters. These results illustrate an extreme case of the effect of TEs in TFBS evolution, and suggest a singular way by which they affect host genes by modulating essential transcriptional networks. PMID:24447172
A Molecular Model for Cocaine Binding by the Immunotherapeutic Human/Mouse Chimeric Monoclonal Antibody 2E2
Lape, Michael; Paula, Stefan; Ball, William J.
Immunotherapy by cocaine-binding monoclonal antibodies (mAbs) has emerged as a promising strategy for the treatment of cocaine addiction. The human (?1 heavy chain)/murine (? light chain) chimeric mAb 2E2 has excellent affinity and specificity for cocaine and recent animal studies have demonstrated 2E2's ability in vivo to reduce cocaine levels in the brain as well as alter cocaine self-administration behavior in rats. In this study, we used mAb 2E2 amino acid sequence information to create a homology model for the 3-D structure of its Fv fragment. Subsequent computational docking studies revealed the intermolecular interactions potentially responsible for mAb 2E2's cocaine binding properties. The driving force of cocaine binding was identified as a combination of hydrophobic interactions and a single hydrogen bond between a light chain tyrosine residue and a carbonyl oxygen atom of cocaine. The model also allowed for an in silico evaluation of single/double residue mutations in the heavy and light chain variable regions that might further enhance mAb 2E2's cocaine binding properties. PMID:20185210
Electrophysiological and behavioral activity of (E)-2-hexenal in the granary weevil and its application in food packaging.
Germinara, G S; Conte, A; De Cristofaro, A; Lecce, L; Di Palma, A; Rotundo, G; Del Nobile, M A
The purpose of this work was to develop a biodegradable carrier material to control insect pests in cereal products. To this aim, (E)-2-hexenal was used, being a natural compound with antimicrobial activity that is also commonly adopted as a flavoring agent. Three coating layers of polycaprolactone (PCL) were spread onto the internal side of a paperboard carton, the first being the active coating containing (E)-2-hexenal. The antennal sensitivity of Sitophilus granarius to a broad range of doses of (E)-2-hexenal was first demonstrated. Next, the ability of different concentrations of this compound to disrupt the orientation of adult S. granarius beetles to odors of intact wheat kernels was established in a two-choice pitfall bioassay. In addition, invasion tests were carried out over an 8-week period to highlight the effects of the biobased repellent packaging and their potential persistence. The results demonstrated that during the entire monitoring period, the percentage of S. granarius adults found in cartons coated with (E)-2-hexenal-loaded multilayer PCL was about 10 % of the total number of insects used in the bioassay, very low compared with the respective control samples, thus assessing both the effectiveness and persistence of the repellent system developed. Although the infestation level of treated packages was reduced relative to the infestation levels in the controls, any infestation of food packages is unacceptable to consumers, so further tests are required to determine whether infestation can be completely prevented using (E)-2-hexenal. PMID:22289599
Dioscorea japonica extract down-regulates prostaglandin E2 synthetic pathway and induces apoptosis in lung cancer cells
Suzuki-Yamamoto, Toshiko; Tanaka, Sayuri; Tsukayama, Izumi; Takafuji, Miki; Hanada, Takae; Arakawa, Toshiya; Kawakami, Yuki; Kimoto, Masumi; Takahashi, Yoshitaka
Prostaglandin E2 plays a role in an array of pathophysiological responses, including inflammation, carcinogenesis and so on. Prostaglandin E2 is synthesized from arachidonic acid by the enzymes cyclooxygenase and prostaglandin E synthase. In some pathological conditions, the isozymes cyclooxygenase-2 and microsomal prostaglandin E synthase-1 are transiently induced, leading to prostaglandin E2 overproduction. The present study showed that Dioscorea japonica extract suppresses mRNA expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 in human non-small-cell lung carcinoma A549 cells in a dose-dependent manner. The suppressive effects of Dioscorea japonica extract on the expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 were confirmed by Western blotting, cyclooxygenase activity and prostaglandin E2 production. Dioscorea japonica extract induced the translocation of nuclear factor-?B from the nucleus to the cytosol and inhibited the activity of the cyclooxygenase-2 promoter. Furthermore Dioscorea japonica extract suppressed the expression of the anti-apoptotic factor B-cell chronic lymphocytic leukemia/lymphoma 2 and enhanced apoptotic terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive intensity in A549 cells. These results suggest that Dioscorea japonica extract suppresses the expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1, with the regulation of the transcriptional activity of cyclooxygenase-2, and induces apoptosis in cancer cells. Thus, Dioscorea japonica may contribute to the prevention of prostaglandin E2-mediated pathophysiological responses such as carcinogenesis and inflammation. PMID:25411520
Presentation of the hydrophilic domains of hepatitis C viral E2 envelope glycoprotein on hepatitis B surface antigen particles.
Lee, I H; Kim, C H; Ryu, W S
Subviral particles of hepatitis B virus have been used to present foreign epitopes. We attempted to present the hydrophilic domains of E2 envelope protein of hepatitis C virus (HCV) as a fusion protein with hepatitis B virus surface antigen (HBsAg). The five hydrophilic domains of HCV E2 antigen were inserted into HBsAg such that the inserted hydrophilic domains were presented on the outer surface of HBV subviral particles. In addition, a fusion encoding the hypervariable region (HVR) of E2 antigen was also made. Cell lysate and culture medium were analyzed for the synthesis and secretion of the fusion proteins by immunoprecipitation with polyclonal anti-HBsAg antibody using recombinant vaccinia virus system. The results showed that the fusion proteins containing these six E2 domains were made in the cell, but only two out of six fusion proteins were secreted into culture medium. Further, cesium chloride density gradient analysis and electron microscopy revealed that these fusions were secreted into culture media as particles. It will be of interest to test immunogenicity of the HBsAg fusion particles containing the HCV E2 domains in animal model. PMID:8915880
Dioscorea japonica extract down-regulates prostaglandin E2 synthetic pathway and induces apoptosis in lung cancer cells.
Suzuki-Yamamoto, Toshiko; Tanaka, Sayuri; Tsukayama, Izumi; Takafuji, Miki; Hanada, Takae; Arakawa, Toshiya; Kawakami, Yuki; Kimoto, Masumi; Takahashi, Yoshitaka
Prostaglandin E2 plays a role in an array of pathophysiological responses, including inflammation, carcinogenesis and so on. Prostaglandin E2 is synthesized from arachidonic acid by the enzymes cyclooxygenase and prostaglandin E synthase. In some pathological conditions, the isozymes cyclooxygenase-2 and microsomal prostaglandin E synthase-1 are transiently induced, leading to prostaglandin E2 overproduction. The present study showed that Dioscorea japonica extract suppresses mRNA expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 in human non-small-cell lung carcinoma A549 cells in a dose-dependent manner. The suppressive effects of Dioscorea japonica extract on the expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 were confirmed by Western blotting, cyclooxygenase activity and prostaglandin E2 production. Dioscorea japonica extract induced the translocation of nuclear factor-?B from the nucleus to the cytosol and inhibited the activity of the cyclooxygenase-2 promoter. Furthermore Dioscorea japonica extract suppressed the expression of the anti-apoptotic factor B-cell chronic lymphocytic leukemia/lymphoma 2 and enhanced apoptotic terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive intensity in A549 cells. These results suggest that Dioscorea japonica extract suppresses the expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1, with the regulation of the transcriptional activity of cyclooxygenase-2, and induces apoptosis in cancer cells. Thus, Dioscorea japonica may contribute to the prevention of prostaglandin E2-mediated pathophysiological responses such as carcinogenesis and inflammation. PMID:25411520
Apoptosis induction by E2F-1 via adenoviral-mediated gene transfer results in growth suppression of head and neck squamous cell carcinoma cell lines
Ta-Jen Liu; Mary Wang; Randall L Breau; Ying Henderson; Adel K El-Naggar; Kimberly D Steck; Michael W Sicard; Gary L Clayman
E2F-1, a transcription factor by discovery, is thought to play a crucial role in regulating G1\\/S cell cycle progression. Its activity is modulated by complex formation with the retinoblastoma protein and related proteins. Overexpression of E2F-1 has been shown to induce apoptosis in quiescent fibroblasts. We constructed a recombinant E2F-1 adenovirus to test whether an overexpression of E2F-1 in head
1.2 TENSOR CONCEPTS AND TRANSFORMATIONS For e1, e2, e3 independent orthogonal unit vectors (base vectors), we may write any vector A as
California at Santa Cruz, University of
35 §1.2 TENSOR CONCEPTS AND TRANSFORMATIONS For e1, e2, e3 independent orthogonal unit vectors (base vectors), we may write any vector A as A = A1 e1 + A2 e2 + A3 e3 where (A1, A2, A3 vectors and A = (A · e1) e1 + (A · e2) e2 + (A · e3) e3. Select any three independent orthogonal vectors
Induction of immune responses in mice and pigs by oral administration of classical swine fever virus E2 protein expressed in rice calli.
Jung, Myunghwan; Shin, Yun Ji; Kim, Ju; Cha, Seung-Bin; Lee, Won-Jung; Shin, Min-Kyoung; Shin, Seung Won; Yang, Moon-Sik; Jang, Yong-Suk; Kwon, Tae-Ho; Yoo, Han Sang
Classical swine fever (CSF), caused by the CSF virus (CSFV), is a highly contagious disease in pigs. In Korea, vaccination using a live-attenuated strain (LOM strain) has been used to control the disease. However, parenteral vaccination using a live-attenuated strain still faces a number of problems related to storage, cost, injection stress, and differentiation of CSFV infected and vaccinated pigs. Therefore, two kinds of new candidates for oral vaccination have been developed based on the translation of the E2 gene of the SW03 strain, which was isolated from an outbreak of CSF in 2002 in Korea, in transgenic rice calli (TRCs) from Oriza sativa L. cv. Dongjin to express a recombinant E2 protein (rE2-TRCs). The expression of the recombinant E2 protein (rE2) in rE2-TRCs was confirmed using Northern blot, SDS-PAGE, and Western blot analysis. Immune responses to the rE2-TRC in mice and pigs were investigated after oral administration. The administration of rE2-TRCs increased E2-specific antibodies titers and antibody-secreting cells when compared to animals receiving the vector alone (p < 0.05 and p < 0.01). In addition, mice receiving rE2-TRCs had a higher level of CD8+ lymphocytes and Th1 cytokine immune responses to purified rE2 (prE2) in vitro than the controls (p < 0.05 and p < 0.01). Pigs receiving rE2-TRCs also showed an increase in IL-8, CCL2, and the CD8+ subpopulation in response to stimulation with prE2. These results suggest that oral administration of rE2-TRCs can induce E2-specific immune responses. PMID:25091740
Transcription Factor E2F-1 Is Upregulated in Response to DNA Damage in a Manner Analogous to That of p53
The transcription factor E2F-1 directs the expression of genes that induce or regulate cell division, and a role for E2F-1 in driving cells into apoptosis is the subject of intense discussion. Recently it has been shown that E2F-1 binds and coprecipitates with the mouse double-minute chromosome 2 protein (Mdm2). A domain of E2F-1 (amino acids 390 to 406) shows striking
Presence of bovine viral diarrhea virus (BVDV) E2 glycoprotein in VSV recombinant particles and induction of neutralizing BVDV antibodies in mice.
Grigera, P R; Marzocca, M P; Capozzo, A V; Buonocore, L; Donis, R O; Rose, J K
We generated a recombinant vesicular stomatitis virus (VSV-E2) encoding the bovine viral diarrhea virus (BVDV) E2 glycoprotein with the VSV-G protein signal peptide. Infection of BHK21 cells with VSV-E2 induced the synthesis of a recombinant E2 (rE2) that comigrated with authentic BVDV-E2 in PAGE-SDS gels. Non-reducing immunoblots showed that rE2 is a disulfide bond-linked homodimer with at least 10-fold higher avidity for conformation-dependent anti-BVDV-E2 antibodies than its reduced monomeric counterpart. Immunofluorescence microscopy also showed that rE2 was transported to the plasma membrane of infected cells and analysis of purified particles demonstrated that dimeric rE2 was incorporated into VSV-E2 virions in approximately 1:10 ratio with respect to the G glycoprotein. BALB/c mice inoculated intranasally with VSV-E2 doses of up to 10(7) plaque forming units (pfu) showed no symptoms of viral-induced disease and developed a specific BVDV neutralizing response that lasted for at least 180 days post inoculation. PMID:10989181
Vaginal Lactobacillus gasseri CMUL57 can inhibit herpes simplex type 2 but not Coxsackievirus B4E2.
Kassaa, Imad Al; Hober, Didier; Hamze, Monzer; Caloone, Delphine; Dewilde, Anny; Chihib, Nour-Eddine; Drider, Djamel
This study aimed at demonstrating the antiviral activity of Lactobacillus gasseri CMUL57 (L. gasseri CMUL57), L. acidophilus CMUL67 and L. plantarum CMUL140 against herpes simplex type 2 (HSV-2) and Coxsackievirus B4E2 (CVB4E2), which are enveloped and naked viruses, respectively. These lactobacilli were non-cytotoxic and were able to reduce the cytopathic effect induced by HSV-2 in Vero cell monolayers. However, lactobacilli were not active against CVB4E2. Tested lactobacilli displayed anti-HSV-2 activity when they were co-incubated with the virus prior to inoculating the mixture to Vero cell monolayers. The detection of HSV-2 DNA by PCR in pellets of bacteria/virus mixtures let us to hypothesize that anti-HSV-2 activity of lactobacilli resulted from the viruses' entrapment. This study showed the capabilities of vaginal lactobacilli to inhibit enveloped viruses such as HSV-2. PMID:25752765
Colicin E2 Expression in Lactobacillus brevis DT24, A Vaginal Probiotic Isolate, against Uropathogenic Escherichia coli
Trivedi, Disha
Novel therapeutic approaches are needed to combat the urinary tract infection in women. During menstruation elevated protein concentration and increase in oxygen and carbon dioxide concentrations with decrease in vaginal Lactobacilli all together contribute to urinary tract infections. Lactobacillus species are a predominant member of the vaginal microflora and are critical in the prevention of a number of urogenital diseases. In order to increase antimicrobial potential of vaginal Lactobacilli, bacteriocin colicin E2 which has specific activity against uropathogenic Escherichia coli has been overexpressed in vaginal probiotic Lactobacillus brevis DT24. Recombinant Lactobacillus brevis DT24 expressing colicin E2 showed much higher inhibitory activity against uropathogenic Escherichia coli than wild type L. brevis DT24 in vitro. Efficacy of probiotic Lactobacillus brevis DT24 expressing colicin E2 protein is required for further in vivo evaluation. PMID:24649377
Characterization of the prostaglandin E2 sensitive (EP)-receptor in the rat isolated trachea.
Lydford, S. J.; McKechnie, K.
1. Using a range of natural and synthetic prostanoid receptor agonists and antagonists, we have shown that the rat isolated trachea contains a heterogeneous population of prostaglandin receptor sub-types mediating both relaxation and contraction of the smooth muscle. Prostaglandin E2 (PGE2) elicits smooth muscle relaxation of pre-contracted preparations, the responses being well defined, with a mean potency (p[A50]) of 7.81 +/- 0.05. 2. 11-deoxy PGE1 16,16-dimethyl PGE2 and misoprostol were all full agonists at this receptor, whilst AH13205 was a low potency agonist, and sulprostone was inactive. 3. The EP1 receptor antagonist, AH6809 (5 microM), and the selective DP receptor antagonist, BW A868C (0.1 microM), had no significant effect on the concentration-effect (E/[A]) curves to PGE2. 4. The putative EP4-receptor antagonist, AH23848B, produced non-competitive antagonism of the PGE2 response curves; pA2 values of 5.07 +/- 0.15 and 5.24 +/- 0.19 were obtained at concentrations of 30 microM and 100 microM respectively. 5. The synthetic thromboxane A2 mimetic, U46619, caused smooth muscle contractions, with a mean p[A50] of 6.90 +/- 0.11. This response was antagonized by the TP receptor antagonist, GR32191B, yielding a mean pA2 of 8.31. 6. At concentrations of 1 microM and above, prostaglandin D2 (PGD2) and the IP-receptor agonist, cicaprost, generally elicited concentration-dependent relaxations of the rat trachea. Prostaglandin F2 alpha (PGF2 alpha) was without affinity or efficacy. 7. These data suggest that the rat isolated trachea contains EP-receptors, TP-receptors, and few, if any DP, IP or FP-receptors.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8032634
Exact Solutions of an Extended Bose-Hubbard Model with E 2 Symmetry
NASA Astrophysics Data System (ADS)
Pan, Feng; Zhang, Ningyun; Wang, Qianyun; Draayer, J. P.
An extended Bose-Hubbard (BH) model with number-dependent multi-site and infinite-range hopping is proposed, which, similar to the original BH model, describes a phase transition between the delocalized superfluid (SF) phase and localized Mott insulator (MI) phase. It is shown that this extended model with local Euclidean E 2 symmetry is exactly solvable when on-site local potentials are included, while the model without local potentials is quasi-exactly solvable, which means only a part of the excited states including the ground state being exactly solvable. As applications of the exact solution for the ground state, phase diagram of the model in 1D without local potential and on-site disorder for filling factor ? = 1 with M = 6, M = 10, and M = 14 sites are obtained. The ground state probabilities to detect n particles on a single site, P n , for n = 0, 1, 2 as functions of the control parameter U/ t in these cases are also calculated. It is shown that the critical point in P n and in the entanglement measure is away from that of the SF-MI transition determined in the phase analysis. It is also shown that the model-independent entanglement measure is related with P n , which, therefore, may be practically useful because P n is measurable experimentally. The ground state expectation value of local particle numbers, the ground state local particle number fluctuations, the ground state probabilities to detect n particles on every site, and the entanglement measure have also been studied in the model for N = M = 4 with the two-body onsite repulsion and a local confining harmonic potential. The connection between these quantities and the entanglement observed previously is verified.
Carnosol and Carnosic Acids from Salvia officinalis Inhibit Microsomal Prostaglandin E2 Synthase-1
Bauer, Julia; Kuehnl, Susanne; Rollinger, Judith M.; Scherer, Olga; Northoff, Hinnak; Stuppner, Hermann; Werz, Oliver; Koeberle, Andreas
Prostaglandin E2 (PGE2), the most relevant eicosanoid promoting inflammation and tumorigenesis, is formed by cyclooxygenases (COXs) and PGE2 synthases from free arachidonic acid. Preparations of the leaves of Salvia officinalis are commonly used in folk medicine as an effective antiseptic and anti-inflammatory remedy and possess anticancer activity. Here, we demonstrate that a standard ethyl acetate extract of S. officinalis efficiently suppresses the formation of PGE2 in a cell-free assay by direct interference with microsomal PGE2 synthase (mPGES)-1. Bioactivity-guided fractionation of the extract yielded closely related fractions that potently suppressed mPGES-1 with IC50 values between 1.9 and 3.5 ?g/ml. Component analysis of these fractions revealed the diterpenes carnosol and carnosic acid as potential bioactive principles inhibiting mPGES-1 activity with IC50 values of 5.0 ?M. Using a human whole-blood assay as a robust cell-based model, carnosic acid, but not carnosol, blocked PGE2 generation upon stimulation with lipopolysaccharide (IC50 = 9.3 ?M). Carnosic acid neither inhibited the concomitant biosynthesis of other prostanoids [6-keto PGF1?, 12(S)-hydroxy-5-cis-8,10-trans-heptadecatrienoic acid, and thromboxane B2] in human whole blood nor affected the activities of COX-1/2 in a cell-free assay. Together, S. officinalis extracts and its ingredients carnosol and carnosic acid inhibit PGE2 formation by selectively targeting mPGES-1. We conclude that the inhibitory effect of carnosic acid on PGE2 formation, observed in the physiologically relevant whole-blood model, may critically contribute to the anti-inflammatory and anticarcinogenic properties of S. officinalis. PMID:22511203
Carnosol and carnosic acids from Salvia officinalis inhibit microsomal prostaglandin E2 synthase-1.
Bauer, Julia; Kuehnl, Susanne; Rollinger, Judith M; Scherer, Olga; Northoff, Hinnak; Stuppner, Hermann; Werz, Oliver; Koeberle, Andreas
Prostaglandin E(2) (PGE(2)), the most relevant eicosanoid promoting inflammation and tumorigenesis, is formed by cyclooxygenases (COXs) and PGE(2) synthases from free arachidonic acid. Preparations of the leaves of Salvia officinalis are commonly used in folk medicine as an effective antiseptic and anti-inflammatory remedy and possess anticancer activity. Here, we demonstrate that a standard ethyl acetate extract of S. officinalis efficiently suppresses the formation of PGE(2) in a cell-free assay by direct interference with microsomal PGE(2) synthase (mPGES)-1. Bioactivity-guided fractionation of the extract yielded closely related fractions that potently suppressed mPGES-1 with IC(50) values between 1.9 and 3.5 ?g/ml. Component analysis of these fractions revealed the diterpenes carnosol and carnosic acid as potential bioactive principles inhibiting mPGES-1 activity with IC(50) values of 5.0 ?M. Using a human whole-blood assay as a robust cell-based model, carnosic acid, but not carnosol, blocked PGE(2) generation upon stimulation with lipopolysaccharide (IC(50) = 9.3 ?M). Carnosic acid neither inhibited the concomitant biosynthesis of other prostanoids [6-keto PGF(1?), 12(S)-hydroxy-5-cis-8,10-trans-heptadecatrienoic acid, and thromboxane B(2)] in human whole blood nor affected the activities of COX-1/2 in a cell-free assay. Together, S. officinalis extracts and its ingredients carnosol and carnosic acid inhibit PGE(2) formation by selectively targeting mPGES-1. We conclude that the inhibitory effect of carnosic acid on PGE(2) formation, observed in the physiologically relevant whole-blood model, may critically contribute to the anti-inflammatory and anticarcinogenic properties of S. officinalis. PMID:22511203
Configuration and Assessment of the GISS ModelE2 Contributions to the CMIP5 Archive
NASA Technical Reports Server (NTRS)
Schmidt, Gavin A.; Kelley, Max; Nazarenko, Larissa; Ruedy, Reto; Russell, Gary L.; Aleinov, Igor; Bauer, Mike; Bauer, Susanne E.; Bhat, Maharaj K.; Bleck, Rainer; Canuto, Vittorio; Clune, Thomas L.; Fainchtein, Rosalinda de; Genio, Anthony Del; Kiang, Nancy Y.; Lacis, Andy A.; LeGrande, Allegra N.; Matthews, Elaine E.; Miller, Ron L.; Oloso, Amidu O.; Putman, William M.; Rind, David; Shindell, Drew T.; Syed, Rahman A.; Zhang, Jinlun
We present a description of the ModelE2 version of the Goddard Institute for Space Studies (GISS) General Circulation Model (GCM) and the configurations used in the simulations performed for the Coupled Model Intercomparison Project Phase 5 (CMIP5). We use six variations related to the treatment of the atmospheric composition, the calculation of aerosol indirect effects, and ocean model component. Specifically, we test the difference between atmospheric models that have noninteractive composition, where radiatively important aerosols and ozone are prescribed from precomputed decadal averages, and interactive versions where atmospheric chemistry and aerosols are calculated given decadally varying emissions. The impact of the first aerosol indirect effect on clouds is either specified using a simple tuning, or parameterized using a cloud microphysics scheme. We also use two dynamic ocean components: the Russell and HYbrid Coordinate Ocean Model (HYCOM) which differ significantly in their basic formulations and grid. Results are presented for the climatological means over the satellite era (1980-2004) taken from transient simulations starting from the preindustrial (1850) driven by estimates of appropriate forcings over the 20th Century. Differences in base climate and variability related to the choice of ocean model are large, indicating an important structural uncertainty. The impact of interactive atmospheric composition on the climatology is relatively small except in regions such as the lower stratosphere, where ozone plays an important role, and the tropics, where aerosol changes affect the hydrological cycle and cloud cover. While key improvements over previous versions of the model are evident, these are not uniform across all metrics.
Interplay between the prostaglandin transporter OATP2A1 and prostaglandin E2-mediated cellular effects.
Bujok, Krystyna; Glaeser, Hartmut; Schuh, Wolfgang; Rau, Tilman T; Schmidt, Ingrid; Fromm, Martin F; Mandery, Kathrin
Prostaglandins such as prostaglandin E2 (PGE2) play a pivotal role in physiological and pathophysiological pathways in gastric mucosa. Little is known about the interrelation of the prostaglandin E (EP) receptors with the prostaglandin transporter OATP2A1 in the gastric mucosa and gastric carcinoma. Therefore, we first investigated the expression of OATP2A1 and EP4 in normal and carcinoma gastric mucosa. Different PGE2-mediated cellular pathways and mechanisms were investigated using human embryonic kidney cells (HEK293) and the human gastric carcinoma cell line AGS stably transfected with OATP2A1. Colocalization and expression of OATP2A1 and EP4 were detected in mucosa of normal gastric tissue and of gastric carcinomas. OATP2A1 reduced the PGE2-mediated cAMP production in HEK293 and AGS cells overexpressing EP4 and OATP2A1. The expression of OATP2A1 in AGS cells resulted in a reduction of [(3)H]-thymidine incorporation which was in line with a higher accumulation of AGS-OATP2A1 cells in S-phase of the cell cycle compared to control cells. In contrast, the expression of OATP2A1 in HEK293 cells had no influence on the distribution in the S-phase compared to control cells. OATP2A1 also diminished the PGE2-mediated expression of interleukin-8 mRNA (IL-8) and hypoxia-inducible-factor 1? (HIF1?) protein in AGS-OATP2A1 cells. The expression of OATP2A1 increased the sensitivity of AGS cells against irinotecan which led to reduced cell viability. Taken together, these data show that OATP2A1 influences PGE2-mediated cellular pathways. Therefore, OATP2A1 needs to be considered as a key determinant for the understanding of the physiology and pathophysiology of prostaglandins in healthy and tumorous gastric mucosa. PMID:25433165
Loss of 15-Hydroxyprostaglandin Dehydrogenase Increases Prostaglandin E2 in Pancreatic Tumors
Pham, Hung; Chen, Monica; Li, Aihua; King, Jonathan; Angst, Eliane; Dawson, David W.; Park, Jenny; Reber, Howard A.; O. Joe, Hines; Eibl, Guido
Objectives Prostaglandin E2 (PGE2) is a product of cyclooxygenase (COX) and prostaglandin E synthase (PGES) and deactivated by 15-hydroxyprostaglandin dehydrogenase (PGDH). Down-regulation of PGDH contributes to PGE2 accumulation in lung and colon cancers but has not been identified in pancreatic cancer. Methods Human pancreatic normal and tumor matched tissues as well as MiaPaCa-2 and BxPC-3 cell lines were assessed for COX-2, mPGES-1, PGDH, SNAI1 and SNAI2 expression by RT-PCR and Western blotting and PGE2 by ELISA. Results Normal tissues exhibited low COX-2 mRNA and protein expression, high PGDH mRNA and protein expression and PGE2 levels at 13 pg/mg protein. In contrast, tumor tissues exhibited high COX-2 mRNA and protein expression, low PGDH mRNA and protein expression and PGE2 levels at 32 pg/mg protein. Tumor tissues exhibited significantly elevated expression of SNAI2 mRNA and protein but not SNAI1 as SNAI1 and SNAI2 reportedly down-regulate PGDH expression. COX-2-positive BxPC-3 but not COX-2-negative MiaPaCa-2 treated with 100 nM of PGE2 induced pERK that was blocked by MEK inhibitor U0126, demonstrating the ability of PGE2 to activate ERK. Conclusions These results suggest that enhanced PGE2 production proceeds through the expression of COX-2 and mPGES-1 and down-regulation of PGDH by SNAI2 in pancreatic tumors. PMID:19820419
Mammalian oocytes are targets for prostaglandin E2 (PGE2) action
Background The ovulatory gonadotropin surge increases synthesis of prostaglandin E2 (PGE2) by the periovulatory follicle. PGE2 actions on granulosa cells are essential for successful ovulation. The aim of the present study is to determine if PGE2 also acts directly at the oocyte to regulate periovulatory events. Methods Oocytes were obtained from monkeys and mice after ovarian follicular stimulation and assessed for PGE2 receptor mRNA and proteins. Oocytes were cultured with vehicle or PGE2 and assessed for cAMP generation, resumption of meiosis, and in vitro fertilization. Results Germinal vesicle intact (GV) oocytes from both monkeys and mice expressed mRNA for the PGE2 receptors EP2, EP3, and EP4. EP2 and EP4 proteins were detected by confocal microscopy in oocytes of both species. Monkey and mouse oocytes responded to PGE2 as well as agonists selective for EP2 and EP4 receptors with elevated cAMP, consistent with previous identification of EP2 and EP4 as G?s/adenylyl cyclase coupled receptors. Incubation of mouse GV stage oocytes with PGE2 delayed oocyte nuclear maturation in vitro, but PGE2 treatment did not alter the percentage of mouse oocytes that fertilized successfully. PGE2 treatment also decreased the percentage of monkey oocytes that resumed meiosis in vitro. In contrast with mouse oocytes, the percentage of monkey oocytes which fertilized in vitro was lower after treatment with PGE2. Monkey oocytes with intact cumulus showed delayed nuclear maturation, but fertilization rate was not affected by PGE2 treatment. Conclusions Monkey and mouse oocytes express functional PGE2 receptors. PGE2 acts directly at mammalian oocytes to delay nuclear maturation. Surrounding cumulus cells modulate the effect of PGE2 to alter subsequent fertilization. PMID:21040553
Bromodomain and extraterminal proteins suppress NF-E2-related factor 2-mediated antioxidant gene expression.
Michaeloudes, Charalambos; Mercado, Nicolas; Clarke, Colin; Bhavsar, Pankaj K; Adcock, Ian M; Barnes, Peter J; Chung, Kian Fan
Oxidative stress, a pathogenetic factor in many conditions, including chronic obstructive pulmonary disease, arises due to accumulation of reactive oxygen species and defective antioxidant defenses in the lungs. The latter is due, at least in part, to impaired activation of NF-E2-related factor 2 (Nrf2), a transcription factor involved in the activation of antioxidant and cytoprotective genes. The bromodomain and extraterminal (BET) proteins, Brd2, Brd3, Brd4, and BrdT, bind to acetylated lysine residues on histone or nonhistone proteins recruiting transcriptional regulators and thus activating or repressing gene transcription. We investigated whether BET proteins modulate the regulation of Nrf2-dependent gene expression in primary human airway smooth muscle cells and the human monocytic cell line, THP-1. Inhibition of BET protein bromodomains using the inhibitor JQ1+ or attenuation of Brd2 and Brd4 expression using small interfering RNA led to activation of Nrf2-dependent transcription and expression of the antioxidant proteins heme oxygenase-1, NADPH quinone oxidoreductase 1, and glutamate-cysteine ligase catalytic subunit. Also, JQ1+ prevented H2O2-induced intracellular reactive oxygen species production. By coimmunoprecipitation, BET proteins were found to be complexed with Nrf2, whereas chromatin-immunoprecipitation studies indicated recruitment of Brd2 and Brd4 to Nrf2-binding sites on the promoters of heme oxygenase-1 and NADPH quinone oxidoreductase 1. BET proteins, particularly Brd2 and Brd4, may play a key role in the regulation of Nrf2-dependent antioxidant gene transcription and are hence an important target for augmenting antioxidant responses in oxidative stress-mediated diseases. PMID:24733848
Argon laser irradiation of rabbits' eyes-changes in prostaglandin E2 levels
Naveh, N.; Peer, J.; Bartov, E.; Weissman, C. (Tel Aviv Univ., Tel Hashomer (Israel))
Laser irradiation of the eye is a widely used therapeutic measure in various ocular disorders. We investigated in laser-treated rabbits' eyes the changes in prostaglandin E2 (PGE2) levels of the tissue affected by the laser (the retina/choroid) and of its adjacent vitreous over a two-week period. The parameters studied were; PGE2 in vitro production by the retina/choroid, as well as PGE2 and protein levels in the vitreous, the latter indicative of a break in the blood retinal barrier (BRB). The effect of noncoherent light exposure used for illumination, and that of the mechanical manipulation involved (sham exposure) were also studied. Following laser exposure vitreal PGE2 levels were increased two-fold above baseline (days three and 14), whereas light exposure resulted in a single peak. PGE2 in vitro production by the retina/choroid in the laser-exposed group was elevated throughout the observation period, peaking twice (days 3 and 14), in the light-exposed group the enhanced production was evident during a shorter period, whereas in the sham group it remained unchanged from baseline. An elevation in vitreal protein levels to above baseline levels occurred in both the laser- and, to a lesser degree, in the noncoherent light-exposed groups, but not in the sham group. Our study demonstrated an enhanced PGE2 in vitro production by retina/choroid of laser-exposed eyes, which might be attributable to the additive effect of the laser induced trauma, and the noncoherent light photochemical changes; the clinical significance of the recurrent increase in vitreal PGE2 levels in laser-treated eyes might be related to its anti-inflammatory properties.
Regulation of sulfated glycosaminoglycan production by prostaglandin E2 in cultured lung fibroblasts
Karlinsky, J.B.; Goldstein, R.H. (Boston Univ. School of Medicine, MA (USA))
Prostaglandin E2 (PGE2) has been shown to increase the synthesis of hyaluronic acid in cultured fibroblasts by increasing the activity of hyaluronate synthetase, a group of plasma membrane-bound synthetic enzymes. We examined whether PGE2 also increased the activity of those enzyme systems involved in the synthesis of sulfated glycosaminoglycan in the human embryonic lung fibroblast. Exposure of cells to PGE2 resulted in dose-dependent increases in glucosamine incorporation into all sulfated glycosaminoglycan subtypes. PGE2 at 10(-7) mol/L increased total glycosaminoglycan per dish to 21.6 +/- 3.1 micrograms versus 12.0 +/- 2.5 micrograms in control untreated cultures. Stimulation of endogenous PGE2 production by bradykinin had a similar effect on glycosaminoglycan synthesis. To examine whether PGE2 affected sulfated glycosaminoglycan protein core production, cells were labeled with tritiated glucosamine in the presence of cycloheximide. Under these conditions, incorporation of radiolabel into all glycosaminoglycan subtypes was reduced. However, when exogenous sulfated glycosaminoglycan chain initiator (p-nitrophenyl beta-D-xyloside) was added, incorporation of tritiated glucosamine into sulfated glycosaminoglycan increased but not to levels found in control cultures. Application of PGE2 to cultures treated with cycloheximide alone, or to cultures treated with cycloheximide plus xyloside, increased tritiated glucosamine incorporation into chondroitin, dermatan sulfate, and to a lesser extent into heparan sulfate. We conclude that PGE2 stimulates synthesis of all sulfated glycosaminoglycan even in the absence of new protein core production, probably by increasing activities of sulfated glycosaminoglycan synthetase enzymes. PGE2 stimulation of heparan sulfate synthesis is partially dependent on the availability of heparan sulfate-specific protein core.
Intrauterine Group A Streptococcal Infections are Exacerbated by Prostaglandin E2
Mason, Katie L.; Rogers, Lisa M.; Soares, Elyara M.; Bani-Hashemi, Tara; Downward, John Erb; Agnew, Dalen; Peters-Golden, Marc; Weinberg, Jason B.; Crofford, Leslie J.; Aronoff, David M.
Streptococcus pyogenes(Group A Streptococcus; GAS) is a major cause of severe postpartum sepsis, a reemerging cause of maternal morbidity and mortality worldwide. Immunological alterations occur during pregnancy to promote maternofetal tolerance, which may increase the risk for puerperal infection. Prostaglandin E2 (PGE2) is an immunomodulatory lipid that regulates maternofetal tolerance, parturition, and innate immunity. The extent to which PGE2 regulates host immune responses to GAS infections in the context of endometritis is unknown. To address this, both an in vivo mouse intrauterine (i.u.) GAS infection model and an in vitro human macrophage-GAS interaction model were utilized. In C57BL/6 mice, i.u. GAS inoculation resulted in local and systemic inflammatory responses and triggered extensive changes in the expression of eicosanoid pathway genes. The i.u. administration of PGE2 increased the mortality of infected mice, suppressed local IL-6 and IL-17A levels, enhanced neutrophilic inflammation, reduced uterine macrophage populations, and increased bacterial dissemination. A role for endogenous PGE2 in modulating anti-streptococcal host defense was suggested because mice lacking the genes encoding the microsomal PGE2 synthase-1 or the EP2 receptor were protected from death, as were mice treated with the EP4 receptor antagonist GW627368X. PGE2 also regulated GAS-macrophage interactions. In GAS-infected human THP-1 (macrophage-like) cells, PGE2 inhibited the production of MCP-1 and TNF-? while augmenting IL-10 expression. PGE2 also impaired the phagocytic ability of human placental macrophages, THP-1 cells, and mouse peritoneal macrophages in vitro. Exploring the targeted disruption of PGE2 synthesis and signaling to optimize existing antimicrobial therapies against GAS may be warranted. PMID:23913961
Pyrrole alkanoic acid derivatives as nuisance inhibitors of microsomal prostaglandin E2 synthase-1.
Wiegard, Andrea; Hanekamp, Walburga; Griessbach, Klaus; Fabian, Jörg; Lehr, Matthias
Microsomal prostaglandin E(2) synthase-1 (mPGES-1) is an enzyme, which is induced during the inflammatory response. Therefore, inhibitors of this enzyme are considered to be potential anti-inflammatory drugs. We have identified 3-(4-dodecanoyl-1,3,5-trimethylpyrrol-2-yl)propionic acid (12) as submicromolar inhibitor of mPGES-1. Surprisingly, structural variations made around this lead only resulted in a relatively small change of enzyme inhibitory potency. Such flat structure-activity relationships are reported to be typical for so called nuisance inhibitors, which exert their action not by directly binding to the enzyme, but by forming colloid-like aggregates at micromolar and sometimes submicromolar concentrations, which somehow sequester and inhibit enzyme targets without specificity. Since aggregate-based inhibition is highly sensitive to non-ionic detergents such as Triton X-100, we investigated some of our compounds for inhibition of human recombinant mPGES-1 also in presence of this detergent. The pyrrole derivatives 12, 67 and 81, which exhibited IC(50) values in absence of Triton X-100 in the range of 0.1 and 1?M, were virtually inactive at the highest test concentration of 10?M when 0.1% of the detergent was added. In the same way, the published mPGES-1 inhibitor 2-[(4-{[(1,1'-biphenyl)-4-ylmethyl]amino}-6-chloropyrimidin-2-yl)thio]octanoic acid (Cay10589) (6) totally lost its activity under these conditions. Therefore, these compounds have to be judged as nuisance inhibitors of the enzyme. In contrast, the known indole derivative 3-[3-(tert-butylthio)-1-(4-chlorobenzyl)-5-isopropylindol-2-yl]-2,2-dimethylpropionic acid (MK-886) (2) showed a considerable activity (75% inhibition at 10?M) also in the presence of Triton X-100. PMID:22209272
Transient receptor potential channels mediate the tussive response to prostaglandin E2 and bradykinin
Grace, Megan; Birrell, Mark A; Dubuis, Eric; Maher, Sarah A
Background Cough is the most frequent reason for consultation with a family doctor, or with a general or respiratory physician. Treatment options are limited and a recent meta-analysis concluded that over-the-counter remedies are ineffective and there is increasing concern about their use in children. Endogenous inflammatory mediators such as prostaglandin E2 (PGE2) and bradykinin (BK), which are often elevated in respiratory disease states, are also known to cause cough by stimulating airway sensory nerves. However, how this occurs is not understood. Methods We hypothesised that the transient receptor potential (TRP) channels, TRPA1 and TRPV1, may have a role as 'common effectors' of tussive responses to these agents. We have employed a range of in vitro imaging and isolated tissue assays in human, murine and guinea pig tissue and an in vivo cough model to support this hypothesis. Results Using calcium imaging we demonstrated that PGE2 and BK activated isolated guinea pig sensory ganglia and evoked depolarisation (activation) of vagal sensory nerves, which was inhibited by TRPA1 and TRPV1 blockers (JNJ17203212 and HC-030031). These data were confirmed in vagal sensory nerves from TRPA1 and TRPV1 gene deleted mice. TRPV1 and TRPA1 blockers partially inhibited the tussive response to PGE2 and BK with a complete inhibition obtained in the presence of both antagonists together in a guinea pig conscious cough model. Conclusion This study identifies TRPA1 and TRPV1 channels as key regulators of tussive responses elicited by endogenous and exogenous agents, making them the most promising targets currently identified in the development of anti-tussive drugs. PMID:22693178
Prostaglandin E2 promotes proliferation of skeletal muscle myoblasts via EP4 receptor activation.
Mo, Chenglin; Zhao, Ruonan; Vallejo, Julian; Igwe, Orisa; Bonewald, Lynda; Wetmore, Lori; Brotto, Marco
We recently demonstrated that conditioned media (CM) from osteocytes enhances myogenic differentiation of myoblasts, suggesting that signaling from bone may be important for skeletal muscle myogenesis. The effect of CM was closely mimicked by prostaglandin E2 (PGE2), a bioactive lipid mediator in various physiological or pathological conditions. PGE2 is secreted at high levels by osteocytes and such secretion is further enhanced under loading conditions. Although four types of receptors, EP1 to EP4, mediate PGE2 signaling, it is unknown whether these receptors play a role in myogenesis. Therefore, in this study, the expression of EPs in mouse primary myoblasts was characterized, followed by examination of their roles in myoblast proliferation by treating myoblasts with PGE2 or specific agonists. All four PGE2 receptor mRNAs were detectable by quantitative real-time PCR (qPCR), but only PGE2 and EP4 agonist CAY 10598 significantly enhance myoblast proliferation. EP1/EP3 agonist 17-phenyl trinor PGE2 (17-PT PGE2) and EP2 agonist butaprost did not have any significant effects. Moreover, treatment with EP4 antagonist L161,982 dose-dependently inhibited myoblast proliferation. These results were confirmed by cell cycle analysis and the gene expression of cell cycle regulators. Concomitant with the inhibition of myoblast proliferation, treatment with L161,982 significantly increased intracellular reactive oxygen species (ROS) levels. Cotreatment with antioxidant N-acetyl cysteine (NAC) or sodium ascorbate (SA) successfully reversed the inhibition of myoblast proliferation and ROS overproduction caused by L161,982. Therefore, PGE2 signaling via the EP4 receptor regulates myogenesis by promoting myoblast proliferation and blocking this receptor results in increased ROS production in myoblasts. PMID:25785867
Prostaglandin E2 inhibits spontaneous inhibitory postsynaptic currents in rat supraoptic neurones via presynaptic EP receptors.
Ibrahim, N; Shibuya, I; Kabashima, N; Sutarmo, S V; Ueta, Y; Yamashita, H
Prostaglandin E2 (PGE2) has been implicated in the excitatory regulation of magnocellular neurones in the supraoptic nucleus (SON). We have recently reported that PGE2 excited SON neurones by directly activating postsynaptic PGE2 receptors (EP receptors) of a subclass other than EP1-3, but did not affect excitatory postsynaptic currents (EPSCs). In the present study, we examined presynaptic effects of PGE2 on rat SON neurones by measuring spontaneous inhibitory postsynaptic currents (IPSCs) by a slice patch-clamp technique. PGE2 inhibited spontaneous IPSCs in a dose-dependent and reversible manner. PGE2 selectively suppressed the frequency of IPSCs without affecting the amplitude of IPSCs in the presence of tetrodotoxin, a blocker of Na+ channels, indicating that the effects were presynaptic. The inhibitory effects of PGE2 on the frequency of IPSCs were mimicked by the EP1/EP3 agonists, 17PT-PGE2 and sulprostone, and the EP2/EP3 agonist, misoprostol, whereas the EP2 agonist, butaprost, or the FP agonist, fluprostenol, had little effect. The effects of PGE2 on IPSCs were unaffected by the selective EP1 antagonist, SC-51322. They were unaffected also by antagonists of GABAB and alpha2 adrenergic receptors, which are present at presynaptic terminals of GABA neurones in the SON and cause suppression of spontaneous IPSCs. The inhibitor of PG synthesis, indomethacin, had little effect on spontaneous IPSCs and on the inhibitory effects of PGE2 as well as of the GABAB agonist, baclofen, and noradrenaline. These results suggest that PGE2 inhibits release of GABA from the GABAergic terminals innervating SON neurones by activating presynaptic EP receptors, presumably of the EP3 subclass, and that such a presynaptic mechanism may play a role in the excitatory regulation of SON neurones by PGE2. PMID:10520139
Transcription addiction: can we garner the Yin and Yang functions of E2F1 for cancer therapy?
Meng, P; Ghosh, R
Classically, as a transcription factor family, the E2Fs are known to regulate the expression of various genes whose products are involved in a multitude of biological functions, many of which are deregulated in diseases including cancers. E2F is deregulated and hyperactive in most human cancers with context dependent, dichotomous and contradictory roles in almost all cancers. Cancer cells have an insatiable demand for transcription to ensure that gene products are available to sustain various biological processes that support their rapid growth and survival. In this context, cutting-off hyperactivity of transcription factors that support transcription dependence could be a valuable therapeutic strategy. However, one of the greatest challenges of targeting a transcription factor is the global effects on non-cancerous cells given that they control cellular functions in general. Recently, there is growing realization regarding the possibility to target the oncogenic activation of transcription factors to modulate transcription addiction without affecting the normal activity required for cell functions. In this review, we used E2F1 as a prototype transcription factor to address transcription factor activity in cancer cell functions. We focused on melanoma considering that E2F1 executes critical functions in response to UV, an etiological factor of cutaneous melanoma and lies immediately downstream of the CDKN2A/pRb axis, which is frequently deregulated in melanoma. Further, activation of E2F1 in melanomas can also occur independent of loss of CDKN2A. Given its activated status and the ability to transcriptionally control a plethora of genes involved in regulating melanoma development and progression, we review the current literature on its differential role in controlling signaling pathways involved in melanoma as well as therapeutic resistance, and discuss the practical value of weaning melanoma cells from E2F1-mediated transcription dependence for melanoma management. PMID:25101673
Triptolide abrogates growth of colon cancer and induces cell cycle arrest by inhibiting transcriptional activation of E2F.
Oliveira, Amanda R; Beyer, Georg; Chugh, Rohit; Skube, Steven J; Majumder, Kaustav; Banerjee, Sulagna; Sangwan, Veena; Li, Lihua; Dawra, Rajinder K; Subramanian, Subbaya; Saluja, Ashok K; Dudeja, Vikas
Despite significant progress in diagnostics and therapeutics, over 50 thousand patients die from colorectal cancer annually. Hence, there is urgent need for new lines of treatment. Triptolide, a natural compound isolated from the Chinese herb Tripterygium wilfordii, is effective against multiple cancers. We have synthesized a water soluble analog of triptolide, named Minnelide, which is currently in phase I trial against pancreatic cancer. The aims of the current study were to evaluate whether triptolide/Minnelide is effective against colorectal cancer and to elucidate the mechanism by which triptolide induces cell death in colorectal cancer. Efficacy of Minnelide was evaluated in subcutaneous xenograft and liver metastasis model of colorectal cancer. For mechanistic studies, colon cancer cell lines HCT116 and HT29 were treated with triptolide and the effect on viability, caspase activation, annexin positivity, lactate dehydrogenase release, and cell cycle progression was evaluated. Effect of triptolide on E2F transcriptional activity, mRNA levels of E2F-dependent genes, E2F1- retinoblastoma protein (Rb) binding, and proteins levels of regulator of G1-S transition was also measured. DNA binding of E2F1 was evaluated by chromatin immunoprecipitation assay. Triptolide decreased colon cancer cell viability in a dose- and time-dependent fashion. Minnelide markedly inhibited the growth of colon cancer in the xenograft and liver metastasis model of colon cancer and more than doubles the median survival of animals with liver metastases from colon cancer. Mechanistically, we demonstrate that at low concentrations triptolide induces apoptotic cell death but at higher concentrations it induces cell cycle arrest. Our data suggest that triptolide is able to induce G1 cell cycle arrest by inhibiting transcriptional activation of E2F1. Our data also show that triptolide downregulates E2F activity by potentially modulating events downstream o