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Retriever1300
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Review: How Forage Feeding Early in Life Influences the Growth Rate, Ruminal Environment, and the Establishment of Feeding Behavior in Pre-Weaned Calves.
The provision of forage to pre-weaned calves has been continuously researched and discussed by scientists, though results associated with calf growth and performance have remained inconsistent. Multiple factors, including forage type, intake level, physical form, and feeding method of both solid and liquid feed, can influence the outcomes of forage inclusion on calf performance. In the current review, we summarized published literature in order to get a comprehensive understanding of how early forage inclusion in diets affects calf growth performance, rumen fermentation, microbiota composition, and the development of feeding behavior. A small amount of good quality forage, such as alfalfa hay, supplemented in the diet, is likely to improve calf feed intake and growth rate. Provision of forage early in life may result in greater chewing (eating and ruminating) activity. Moreover, forage supplementation decreases non-nutritive oral and feed sorting behaviors, which can help to maintain rumen fluid pH and increase the number of cellulolytic bacteria in the rumen. This review argues that forage provision early in life has the potential to affect the rumen environment and the development of feeding behavior in dairy calves. Continued research is required to further understand the long-term effects of forage supplementation in pre-weaned calves, because animal-related factors, such as feed selection and sorting, early in life may persist until later in adult life.
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No pos
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Retriever1301
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Ploy and counterploy in predator-prey interactions: Orb-weaving spiders versus bombardier beetles.
Bombardier beetles (Brachinus spp.) offered to orb-weaving spiders are either captured or lost, depending on the attack strategy of the spider. Nephila clavipes grasps a beetle directly and attempts to bite it outright, but is repelled by the beetle's defensive spray. As the spider recovers from the spray, the beetle makes its escape from the web. Argiope first imprisons the beetle by wrapping it delicately in silk, without causing it to spray. When the spider then proceeds to bite, the wrapping protects it against the full effects of the spray. The wrapping strategy may be generally effective against chemically protected insects, and it is suggested that this may be one of its principal adaptive justifications.
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No pos
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No neg
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Retriever1302
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Physiological and morphological responses of Lead or Cadmium exposed Chlorella sorokiniana 211-8K (Chlorophyceae).
The heavy metal pollution in soils and aquatic environments is a serious ecological problem. In the green-microalga Chlorella sorokiniana 211-8K (Chlorophyceae) exposed to ions of lead (Pb) and cadmium (Cd) we studied the metabolic responses to the toxicity of these two heavy metals. Our data indicate that both the pollutants alter the alga cell ultrastructure and its physiological characteristics (growth, photosynthesis, respiration, enzyme activities). The toxic effects of the two metals resulted time-dependent to the exposure. After 24 h of treatment with 250 μM Pb or Cd, photosynthesis was inhibited until to 77 and 86%, however respiration was strongly enhanced up to 300 and 350%, respectively. In the algal cells Pb or Cd exposure induced a reduction in the content of the total chlorophylls and a decrease of the soluble protein levels, significantly compromising the growth, particularly in cultures cadmium-treated. We report data on ultrastructural changes induced by the two heavy metals; they affected overall chloroplast ultrastructure of the alga. Most importantly, the O-acetyl-L-serine(thiol)lyase (OASTL) activity was appreciably increased after only 2 h of Cd exposure, indicating the existence of a link between the metal contamination and cysteine synthesis. Then, Chlorella sorokiniana cells seem to better tolerate high concentrations of Pb while appear to be more sensitive to Cd ions. These results provide some additional information that can lead to better understand consequences of heavy metal poisoning in microalgae.
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Retriever1303
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Dipeptidyl peptidase-4 inhibitor MK-626 restores insulin secretion through enhancing autophagy in high fat diet-induced mice.
Autophagy is cellular machinery for maintenance of β-cell function and mass. The current study aimed to investigate the regulatory effects of MK-626, a dipeptidyl peptidase-4 inhibitor, on insulin secretion through the activation of autophagy in high fat diet-induced obese mice. C57BL/6 mice were fed with a rodent diet containing 45 kcal% fat for 16 weeks to induce obesity and then were received either vehicle or MK-626 (3 mg/kg/day) orally during the final 4 weeks. Mouse islets were isolated. Phosphorylation of serine/threonine-protein kinase mTOR and levels of light chain 3B I (LC3B I), LC3B II, sequestosome-1 (SQSTM1/p62) and autophagy-related protein-7 (Atg7) were examined by Western blotting. Glucagon like-peptide-1 (GLP-1) level and insulin secretion were measured by ELISA. GLP-1 level in plasma was decreased in obese mice, which was elevated by dipeptidyl peptidase-4 inhibitor MK-626. In the islets of obese mice, phosphorylation of mTOR, ratio of LC3B I and LC3B II, and level of p62 were elevated and the expression of Atg7 and insulin secretion were reduced compared to those of C57BL/6 mice. However, such effects were reversed by MK-626. Autophagy activator rapamycin stimulated insulin secretion in obese mice but autophagy inhibitor chloroquine treatment inhibited insulin secretion in obese mice administrated by MK-626. Furthermore, the beneficial effects of MK-626 were inhibited by GLP-1 receptor antagonist exendin 9-39. The present study reveals the activation of autophagy to mediate the anti-diabetic effect of GLP-1.
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Retriever1304
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Non-invasive assessment of left ventricular performance at rest and during exercise by T-M mode echocardiography.
The evaluation methodology of the cardiac performance has had during the last period of time the important contribution of the echocardiography. Sports cardiology is an ideal field for the use of the T-M echocardiography, for the assessment of the left ventricular performance, because of its various possibilities and non-invasive character. The review based on the data of the literature and on the author's experiences in T-M echocardiography, practised on the teenagers at rest and exercise, presents the advantages, the technical difficulties, the work methodology and the limits of the method. The use of this technique allows the measurement of the dimensions of the interventricular septum, of the posterior wall of the left ventricle and its cavity, and the dimension of the aorta; the monitoring of the valvular dynamics of the mitral and aortic valve, of the interventricular septum and posterior wall of the left ventricle at rest and during exercise; the functional evaluation of the left ventricular inotropic status by means of the determination of the cardiac index, stroke volume, ejection fraction and myocardial contractility; the possibility of a systematical control of the training effects on the development of heart in the case of children practising performance sports; the detection of some cardiac diseases (e.g. cardiomyopathy, septal hypertrophy, "silent" mitral valve prolapse), which limit the adaptation of the heart to effort. Though there are a lot of studies, the author considers that the limits of the application of echocardiography in sports medicine cannot yet be seen. The development of the ultrasound machines will allow the extension of the investigation field.
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Retriever1305
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Deep Regionlets: Blended Representation and Deep Learning for Generic Object Detection.
In this article, we propose a novel object detection algorithm named "Deep Regionlets" by integrating deep neural networks and a conventional detection schema for accurate generic object detection. Motivated by the effectiveness of regionlets for modeling object deformations and multiple aspect ratios, we incorporate regionlets into an end-to-end trainable deep learning framework. The deep regionlets framework consists of a region selection network and a deep regionlet learning module. Specifically, given a detection bounding box proposal, the region selection network provides guidance on where to select sub-regions from which features can be learned from. An object proposal typically contains three - 16 sub-regions. The regionlet learning module focuses on local feature selection and transformations to alleviate the effects of appearance variations. To this end, we first realize non-rectangular region selection within the detection framework to accommodate variations in object appearance. Moreover, we design a "gating network" within the regionlet leaning module to enable instance dependent soft feature selection and pooling. The Deep Regionlets framework is trained end-to-end without additional efforts. We present ablation studies and extensive experiments on the PASCAL VOC dataset and the Microsoft COCO dataset. The proposed method yields competitive performance over state-of-the-art algorithms, such as RetinaNet and Mask R-CNN, even without additional segmentation labels.
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No pos
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Retriever1306
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Use of captive-bred monkeys for vaccine production.
Cynomolgus monkeys (Macaca fasicularis) were bred in captivity for the production and control of inactivated poliomyelitis vaccine. Compared to imported wild-caught animals the captive-bred monkeys contracted fewer virus infections, as evidenced by results of serological examination, and yielded remarkably clean cell cultures. These cultures could be grown in series and appear very suitable for the production of viral vaccines.
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No pos
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Retriever1307
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Sex Chromosome Analysis of Postmortem Corneal Endothelium After Sex-Mismatch Descemet Membrane Endothelial Keratoplasty.
PURPOSE
To identify the origin of corneal endothelial cells (host or donor) present on grafts at various time points after Descemet membrane endothelial keratoplasty (DMEK), using fluorescence in situ hybridization (FISH) of sex chromosomes on post mortem corneas with sex mismatch between the donor and host.
METHODS
Corneoscleral buttons of 6 post mortem DMEK eyes of 4 patients, operated for Fuchs endothelial dystrophy, with an average postoperative time of 2.6 (±1.8) years (range, 7 months-4.5 years), of 2.5 (±1.7) years (range, 7 months-4 years), were processed for FISH detection of XX (female) or XY (male)-labeling signals in corneal endothelial cells in the central area of the DMEK graft. Two male patients underwent bilateral DMEK with grafts from female donors, and 2 female patients underwent unilateral DMEK and received a graft from a male donor.
RESULTS
FISH consistently showed the presence of donor endothelial cells across the graft area, with signaling of sex chromosomes opposite to the sex of the host.
CONCLUSIONS
Donor endothelial cells may survive up to 4.5 years after DMEK. If so, the lower incidence of allograft rejection in DMEK may not be explained by early host cell replacement. Potential host cell migration may be limited by donor/recipient cell-cell contact inhibition.
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No pos
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No neg
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Retriever1308
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Alternative polyadenylation of MeCP2: Influence of cis-acting elements and trans-acting factors.
The human MeCP2 gene encodes a ubiquitously expressed methyl CpG binding protein. Mutations in this gene cause a neurodevelopmental disorder called Rett Syndrome (RS). Mutations identified in the coding region of MeCP2 account for approximately 65% of all RS cases. However, 35% of all patients do not show mutations in the coding region of MeCP2, suggesting that mutations in non-coding regions likely exist that affect MeCP2 expression rather than protein function. The gene is unusual in that is has a >8.5 kb 3' untranslated region (3' UTR), and the size of the 3'UTR is differentially regulated in various tissues because of distinct polyadenylation signals. We have identified putative cis-acting auxiliary regulatory elements that play a role in alternative polyadenylation of MeCP2 using an in vivo polyadenylation reporter assay and in a luciferase assay. These cis-acting auxiliary elements are found both upstream and downstream of the core CPSF binding sites. Mutation of one of these cis-acting auxiliary elements, a G-rich element (GRS) significantly reduced MeCP2 polyadenylation efficiency in vivo. We further investigated what trans-acting factor(s) might be binding to this cis-acting element and found that hnRNP F protein binds specifically to the element. We next investigated the MeCP2 3' UTRs by performing quantitative real-time PCR; the data suggest that altered RNA stability is not a major factor in differential MeCP2 3' UTR usage. In sum, the mechanism(s) of regulated alternative 3'UTR usage of MeCP2 are complex, and insight into these mechanisms will aid our understanding of the factors that influence MeCP2 expression.
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No pos
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No neg
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Retriever1309
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Endoscopic ultrasonography for diagnosis of submucosal invasion in early gastric cancer.
Endoscopic ultrasonography (EUS) is considered to be useful for deciding the treatment course for early gastric cancer. To determine reliable indications suggesting submucosal tumor invasion, we retrospectively analyzed EUS images of the hyperechoic third layer, which corresponds to the submucosa. The subjects enrolled in this study were 75 patients, with 78 gastric cancers (diagnosed as mucosal cancer without ulcerous changes on endoscopy and as histologically differentiated adenocarcinoma on biopsy), who were also examined by EUS. We retrospectively classified EUS features of the third layer (submucosa) into five groups: (1) irregular narrowing, (2) budding sign, (3) multiple echo-free spots, (4) unclear, and (5) no changes. In endoscopically diagnosed gastric mucosal cancer, 16 of the 78 lesions were associated with histologic submucosal invasion. EUS features that were associated with a high incidence of histological submucosal tumor invasion were irregular narrowing (submucosal invasion, 60.0%) and the budding sign (85.7%), and 90.9% of lesions with either of these features had submucosal invasion of tumors when tumorous changes in the third layer exceeded 1 mm in depth. Endosonographic irregular narrowing and a budding sign of more than 1 mm in depth in the third layer are useful for the diagnosis of submucosal invasion in gastric cancers that are diagnosed as mucosal cancers without ulcerous change on endoscopy.
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No pos
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No neg
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Retriever1310
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Screening of inhibitors of angiotensin-converting enzyme (ACE) employing high performance liquid chromatography-electrospray ionization triple quadrupole mass spectrometry (HPLC-ESI-QqQ-MS).
Angiotensin-converting enzyme (ACE) plays a key role in regulating blood pressure in the body by converting the angiotensin I (AI) into angiotensin II (AII). Angiotensin II is a potent vaso-active peptide that causes arterioles to constrict, resulting in increased blood pressure. A rapid and sensitive method for the identification of inhibitors of ACE was developed, and optimized employing HPLC-ESI-QqQ-MS. In this assay, angiotensin I substrate was converted into the product angiotensin II with the catalytic action of ACE. A calibration curve for depleting concentration of angiotensin I was developed and linearity of R2=0.999 with a remarkably low concentration of substrate range 20-200nM. The limit of detection and quantification of angiotensin I was found to be 1.93 and 5.84nM, respectively. The enzymatic reaction was optimized for incubation time, concentration, and volume of enzyme and substrate. All reactions were performed at 37°C at pH7.5 with standard incubation time of 20min. Two standard inhibitors, Captopril and Lisinopril, were checked through the newly developed method for their inhibitory potential, and their IC50 values were found to be 3.969 and 0.852μM, respectively. Reproducibility and precision analysis of different experiments showed <9.9% RSD. The developed method can be used for the identification of new ACE inhibitors.
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No pos
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No neg
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Retriever1311
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Hesperidin prevents retinal and plasma abnormalities in streptozotocin-induced diabetic rats.
Diabetic retinopathy is a complex disease that potentially involves increased production of advanced glycosylation end products (AGEs) and elevated aldose reductase (AR) activity, which are related with oxidative stress and inflammation. The aim of this study was to investigate the effects of hesperidin on retinal and plasma abnormalities in streptozotocin-induced diabetic rats. Hesperidin (100, 200 mg/kg daily) was given to diabetic rats for 12 weeks. The blood-retina breakdown (BRB) was determined after 2 weeks of treatment followed by the measurement of related physiological parameters with ELISA kits and immunohistochemistry staining at the end of the study. Elevated AR activity and blood glucose, increased retinal levels of vascular endothelial growth factor (VEGF), ICAM-1, TNF-α, IL-1β and AGEs as well as reduced retina thickness were observed in diabetic rats. Hesperidin treatment significantly suppressed BRB breakdown and increased retina thickness, reduced blood glucose, AR activity and retinal TNF-α, ICAM-1, VEGF, IL-1β and AGEs levels. Furthermore, treatment with hesperidin significantly reduced plasma malondialdehyde (MDA) levels and increased SOD activity in diabetic rats. These data demonstrated that hesperidin attenuates retina and plasma abnormalities via anti-angiogenic, anti-inflammatory and antioxidative effects, as well as the inhibitory effect on polyol pathway and AGEs accumulation.
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No pos
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No neg
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Retriever1312
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Who and how in the regulation of mitochondrial cristae shape and function.
Mitochondrial adaptation to different physiological conditions highly relies on the regulation of mitochondrial ultrastructure, particularly at the level of cristae compartment. Cristae represent the membrane hub where most of the respiratory complexes embed to account for OXPHOS and energy production in the form of adenosine triphosphate (ATP). Changes in cristae number and shape define the respiratory capacity as well as cell viability. The identification of key regulators of cristae morphology and the understanding of their contribution to the mitochondrial ultrastructure and function have become an strategic goal to understand mitochondrial disorders and to exploit as therapeutic targets. This review summarizes the known regulators of cristae ultrastructure and discusses their contribution and implications for mitochondrial dysfunction.
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No pos
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No neg
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Retriever1313
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Glucocorticoids upregulate FOXP3 expression and regulatory T cells in asthma.
BACKGROUND
T regulatory (T reg ) cells are characterized by expression of suppressive cytokines and the transcription factor FOXP3. They play a key role in balancing immune responses and maintain peripheral tolerance against antigens and allergens. The loss of peripheral tolerance against allergens causes diseases that can be therapeutically controlled with glucocorticoids.
OBJECTIVE
The present study investigates whether glucocorticoids affect the activity of T reg cells on the basis of FOXP3 and cytokine expression.
METHODS
CD4 + T cells from healthy donors and glucocorticoid-treated asthmatic patients were isolated, and expression of FOXP3, along with IL-10 and TGF-beta1, was determined. The effect of glucocorticoids on T reg cells was measured in vivo before and after GC treatment and in in vitro cultures.
RESULTS
FOXP3 mRNA expression was significantly increased in asthmatic patients receiving inhaled glucocorticoid treatment, systemic glucocorticoid treatment, or both. FOXP3 tightly correlated with IL10 mRNA expression. No correlation of FOXP3 mRNA expression was observed in relation to a (GT)n microsatellite promoter polymorphism on chromosome Xp11.23 or total IgE level. The frequency of CD25 + memory CD4 + T cells and transient FOXP3 mRNA expression by CD4 + T cells significantly increased after systemic glucocorticoid treatment, whereas TGFB1 expression did not change. Furthermore, glucocorticoids induced IL10 and FOXP3 expression in short-term and long-term cultures in vitro.
CONCLUSION
These findings demonstrate that glucocorticoid treatment is not only immunosuppressive and anti-inflammatory but also promotes or initiates differentiation toward T R 1 cells by a FOXP3-dependent mechanism. Strategies that convert transient glucocorticoid-induced T reg activity into a stable phenotype might improve allergy and asthma therapy.
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No pos
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No neg
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Retriever1314
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Two early descriptions of restless legs syndrome and periodic leg movements by Boissier de Sauvages (1763) and Gilles de la Tourette (1898).
Boissier de Sauvages de La Croix and Gilles de la Tourette, French neurologists, noticed that patients with "anxiety in the lower limbs, shooting pain, tingling legs" may have an insomnia "at the time of wake-sleep transition [and] experience sudden jerks in the lower limbs." Their descriptions confirm that the clinical features of RLS were previously described in French literature in the 18th century.
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No pos
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No neg
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Retriever1315
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Lack of Data-driven Treatment Guidelines and Wide Variation in Management of Chronic Pelvic Pain in Adolescents and Young Adults.
STUDY OBJECTIVE
Current literature lacks data-driven guidelines for surgical treatment of adolescent and young adult (AYA) patients with chronic pelvic pain. We hypothesized that there is a significant variation in treatment of these patients, which might be an indicator of over- or undertreatment by some providers.
DESIGN AND SETTING
We completed a retrospective population-based analysis of the Nationwide Inpatient Sample from 1998 to 2016.
PARTICIPANTS
We included AYA patients aged 9-25 years whose primary diagnosis was adenomyosis, endometriosis, or chronic pelvic pain. Patients who might have undergone pelvic or abdominal procedures for other primary diagnoses were excluded.
INTERVENTIONS AND MAIN OUTCOME MEASURES
Trends of inpatient surgical intervention were calculated. Logistic regression was performed to determine the likelihood of undergoing an intervention, adjusted for patient demographic characteristics.
RESULTS
A total of 13,111 AYA patients were analyzed. Median age at diagnosis was 22 (interquartile range, 20-24) years. The overall inpatient intervention rate was 5879/13111 (45.0%) (2445/5897 (18.6%) for excision/ablation, 2057/5897 (15.7%) for hysterectomy, 1239/5897 (9.5%) for diagnostic laparoscopy, and 156/5897 (1.2%) for biopsy). Rate of hysterectomy increased in the late 2000s while rates of all other interventions decreased. Patients in the northeast were less likely to undergo an intervention than patients in the rest of the country. Rates of intervention also differed according to race, insurance status, and type of hospital.
CONCLUSION
There is wide variation in the use of surgical treatment for chronic pelvic pain in AYA patients across the country and between types of institutions. Of concern, the rate of hysterectomy has increased over time. There is a need for data-directed treatment guidelines for the management of AYA patients with chronic pelvic pain to ensure appropriate application of surgical treatments and expand high-value surgical care.
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No pos
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No neg
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Retriever1316
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Monitoring of Rho GTPase Activity in Podocytes.
The glomerulus is the filtration unit of the kidney, where the first step of urine formation occurs. Podocytes are characterized by their actin-based projections called foot processes. Podocyte foot processes play a critical role in the permselective filtration barrier, along with fenestrated endothelial cells and the glomerular basement membrane. The Rho family of small GTPases (Rho GTPases) is the master regulators of the actin cytoskeleton and functions as molecular switches. Recent studies have shown that disruption of Rho GTPase activity and subsequent changes in foot process structure cause proteinuria. Here, we describe an effector pull-down assay using GST-fusion proteins to monitor the activity of RhoA, Rac1, and Cdc42, which are prototypical Rho GTPases in podocytes.
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No pos
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No neg
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Retriever1317
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The c-FLIPL cleavage product p43FLIP promotes activation of extracellular signal-regulated kinase (ERK), nuclear factor κB (NF-κB), and caspase-8 and T cell survival.
Caspase-8 is now appreciated to govern both apoptosis following death receptor ligation and cell survival and growth via inhibition of the Ripoptosome. Cells must therefore carefully regulate the high level of caspase-8 activity during apoptosis versus the modest levels observed during cell growth. The caspase-8 paralogue c-FLIP is a good candidate for a molecular rheostat of caspase-8 activity. c-FLIP can inhibit death receptor-mediated apoptosis by competing with caspase-8 for recruitment to FADD. However, full-length c-FLIPL can also heterodimerize with caspase-8 independent of death receptor ligation and activate caspase-8 via an activation loop in the C terminus of c-FLIPL. This triggers cleavage of c-FLIPL at Asp-376 by caspase-8 to produce p43FLIP. The continued function of p43FLIP has, however, not been determined. We demonstrate that acute deletion of endogenous c-FLIP in murine effector T cells results in loss of caspase-8 activity and cell death. The lethality and caspase-8 activity can both be rescued by the transgenic expression of p43FLIP. Furthermore, p43FLIP associates with Raf1, TRAF2, and RIPK1, which augments ERK and NF-κB activation, IL-2 production, and T cell proliferation. Thus, not only is c-FLIP the initiator of caspase-8 activity during T cell activation, it is also an initial caspase-8 substrate, with cleaved p43FLIP serving to both stabilize caspase-8 activity and promote activation of pathways involved with T cell growth.
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No pos
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No neg
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Retriever1318
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Effect of 3 growth control substances on foreign body sarcomagenesis: IFN, IUdR, MGBG.
The purpose was to observe the effect on sarcomagenesis of 3 substances reported to inhibit neoplastic growth--interferon alpha-2/alpha-1 hybrid (IFN), 5-iodo-2-deoxyuridine (IUdR) and methylglyoxal bis(guanylhydrazone) (MGBG). Inhibitory effect might help diminish the sarcoma risk of human implants. The substances were applied respectively to groups of 25mm cellulose filters which were implanted subcutaneously 1 per animal in randomly assigned respective groups of 50 female BALB/c mice. The implant sites were palpated weekly. On detection of a tumour the animal was sacrificed. The number of tumours arising and the accumulated weeks of exposure to the implants were recorded per group and compared to those of controls with untreated filters. Tumour incidence in the 2 IFN groups was 33/45 and 35/48 mice--160 per cent that of the controls, 22/48 (chi-square p < 0.05). In the IUdR group tumour incidence was 24/44 mice--194 per cent that of controls (p < 0.05), and in the MGBG group 15/43--122 per cent that of controls (p < 0.75). Although the substances inhibit tumour growth in man, they did not inhibit but increased film sarcomagenesis, not significant for MGBG. Observation of the effects of such substances with dual neoplastic activity may furnish clues to the control processes of neoplasia.
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No pos
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No neg
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Retriever1319
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Adaptive cytoprotection by 0.25 M HCl is truly "cytoprotective" and may not depend upon elevated levels of prostaglandin synthesis.
The ability of a mild irritant to reduce ethanol-induced damage to the rat gastric mucosa was investigated using an ex vivo gastric chamber preparation. Exposure to 0.25 M hydrochloric acid (HCl) did not cause significant damage to the surface epithelium, but did reduce both the lesion area and the extent of superficial epithelial damage caused by subsequent exposure to 40% ethanol (EtOH). "Adaptive cytoprotection" was also demonstrated by the reduction of ethanol-induced changes in transmural potential difference and net K+ efflux, and by rapid recovery of these physiological parameters following the removal of ethanol from the chamber. Pretreatment of rats with indomethacin at a dose that has been shown to significantly inhibit gastric cyclooxygenase activity did not significantly affect the ability of 0.25 M HCl to reduce the effects of ethanol on lesion area, epithelial damage, potential difference, and net K+ efflux.
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No pos
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No neg
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Retriever1320
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Litigation Cases After Post-Bariatric Surgery: Lesson from the Past.
BACKGROUND
Due to the high demand of post-bariatric surgeries, the number of litigation cases is rapidly growing. Even if surgical mistakes still represent one of the main causes of medico-legal issues, many disputes depend on what happens in the post-operative course. In this article we analyzed the litigation cases that occurred in our Plastic Surgery Department, the current literature about medico-legal disputes and the importance of the doctor-patient relationship.
PATIENTS AND METHODS
The medical records of 788 post-bariatric surgeries, the post-operative complications and the related litigation cases from January 2015 to December 2019 were collected, analyzed and compared.
RESULTS
We performed 380 abdominoplasties, 28 torsoplasties, 65 breast reductions, 99 mastopexies, 94 brachioplasties, 52 thighplasties, 65 liposuctions and 5 facelifts between 2015 and 2019. Eight patients complained of medical issues and claimed for litigation. Despite in all cases the judges highlighted the risk of consent misinterpretation, the payout was granted only in one case.
CONCLUSION
Post-bariatric patients often mistake their preoperative condition and consider body contouring procedures as an aesthetic surgery treatment. Patients should be therefore clearly informed about the complexity of body contouring procedures after massive weight loss, which should never be compared to aesthetic surgery. Surgeons should always promote the communication with their patients and build a strong and trustworthy relationship. This attitude will allow to deal more easily with complications and, in the worst situations, with medico-legal litigations.
LEVEL OF EVIDENCE IV
This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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No pos
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Retriever1321
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Spatiotemporal variation in avian migration phenology: citizen science reveals effects of climate change.
A growing number of studies have documented shifts in avian migratory phenology in response to climate change, and yet there is a large amount of unexplained variation in the magnitude of those responses across species and geographic regions. We use a database of citizen science bird observations to explore spatiotemporal variation in mean arrival dates across an unprecedented geographic extent for 18 common species in North America over the past decade, relating arrival dates to mean minimum spring temperature. Across all species and geographic locations, species shifted arrival dates 0.8 days earlier for every °C of warming of spring temperature, but it was common for some species in some locations to shift as much as 3-6 days earlier per °C. Species that advanced arrival dates the earliest in response to warming were those that migrate more slowly, short distance migrants, and species with broader climatic niches. These three variables explained 63% of the interspecific variation in phenological response. We also identify a latitudinal gradient in the average strength of phenological response, with species shifting arrival earlier at southern latitudes than northern latitudes for the same degree of warming. This observation is consistent with the idea that species must be more phenologically sensitive in less seasonal environments to maintain the same degree of precision in phenological timing.
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No pos
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No neg
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Retriever1322
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E-cigarette use as a predictor of cigarette smoking: results from a 1-year follow-up of a national sample of 12th grade students.
OBJECTIVE
To prospectively examine vaping as a predictor of future cigarette smoking among youth with and without previous cigarette smoking experience. A secondary aim is to investigate whether vaping may desensitise youth to the dangers of smoking.
METHODS
Analysis of prospective longitudinal panel data from the nationally representative Monitoring the Future study. The analysis is based on 347 12th grade students who were part of a randomly selected subsample that completed in-school surveys in 2014 and were resurveyed 1-year later.
RESULTS
Among youth who had never smoked a cigarette by 12th grade, baseline, recent vapers were more than 4 times (relative risk (RR)=4.78) more likely to report past-year cigarette smoking at follow-up, even among youth who reported the highest possible level of perceived risk for cigarette smoking at baseline. Among 12th grade students who had smoked in the past but had not recently smoked at baseline, recent vapers were twice (RR=2.15) as likely to report smoking in the past 12 months at the follow-up. Vaping did not predict cessation of smoking among recent smokers at baseline. Among never-smokers at baseline, recent vapers were more than 4 times (RR=4.73) more likely to move away from the perception of cigarettes as posing a 'great risk' of harm, a finding consistent with a desensitisation process.
CONCLUSIONS
These results contribute to the growing body of evidence supporting vaping as a one-way bridge to cigarette smoking among youth. Vaping as a risk factor for future smoking is a strong, scientifically-based rationale for restricting youth access to e-cigarettes.
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No pos
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No neg
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Retriever1323
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Efficacy of Piper (Piperaceae) extracts for control of common home and garden insect pests.
Extracts from three species of the plant family Piperaceae, Piper nigrum [L.], Piper guineense [Schum & Thonn, and Piper tuberculatum [Jacq.], were tested for efficacy against insects from five orders. All three species contain isobutyl amides, plant secondary compounds that act as neurotoxins in insects. These materials are considered safe to mammals because Piper spp. were used for centuries for spice and medicinal purposes. When 24-h P. nigrum LC50 values were compared between common insect pests from eastern Canada and the northeastern United States, the most sensitive species in order of increasing lethal concentration were eastern tent caterpillar, Malacosoma americanum (F.) < European pine sawfly larvae, Neodiprion sertifer (Geoffroy) < spindle ermine moth larvae, Yponomeuta cagnagella [Hübner] < viburnum leaf beetle larvae, Pyrrhalta viburni [Paykull] < stripped cucumber beetle adults, Acalymma vittatum (F.) < Colorado potato beetle adults, Leptinotarsa decemlineata (Say) < Japanese beetle adults, Popillia japonica [Newman] < hairy chinch bug, Blissus leucopterus hirtis [Montandon]. The life stage tested was the point at which each species causes the greatest amount of damage to the host plant and the point at which most gardeners would likely choose to treat with a conventional synthetic insecticide. Greenhouse trials revealed that the pepper formulations also had a repellent activity, thus protecting plant leaves from 1) herbivory (lily leaf beetle, Lilioceris lilii [Scopoli], adults and larvae and stripped cucumber beetle adults) and 2) oviposition [European corn borer, Ostrinia nubilalis (Hübner)]. Combinations with other botanical extracts were additive at best in toxicity and repellent trials. Nontarget toxicity to beneficial invertebrates is a possibility because the P. nigrum LC50 for beneficial ladybird beetles was 0.2%. P. nigrum extracts can provide a reasonable level of control against lepidopteran and European pine sawfly larvae and also will work as a short-term repellent and feeding deterrent. It is recommended that the use of Piper extracts be restricted to small-scale spot treatments in residential areas where insect pest outbreaks have occurred.
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No pos
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No neg
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Retriever1324
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[Relationship between geratic frailty and cognitive dysfunction in the eldly].
OBJECTIVE
To analyze the current situation and correlation between frailty and cognitive dysfunction in the old patients of orthopedic emergency.
METHODS
Enrolling 248 elderly people( ≥65 years old) in orthopedic emergency department of Beijing Jishuitan Hospital from September to December 2018, the cognitive function of the subjects was assessed by Mini-mental State Examination( MMSE). The frailty situation was assessed by FRAIL Scale. In addition, ADL, exercise tolerance assessment, gripping power and geriatric nutritional risk index( GNRI) were also tested in this study.
RESULTS
In this research, 58( 23. 4%) were the elderly with normal cognitive function, 69( 27. 8%) were MCI, and 86( 34. 7%) were dementia and 35( 14. 1%) were severe dementia. The prevalence of seniors over 76 years old was significantly higher than that of the younger age group( χ~2= 39. 300, P < 0. 001), the prevalence of seniors below primary school was significantly higher than that of junior middle school and above( χ~2= 117. 082, P<0. 001), and the prevalence of dementia in patients with chronic obstructive pulmonary disease( COPD) was higher( χ~2= 11. 685, P = 0. 009). The study subjects were strong elderly, accounting for 69( 27. 8%), 114( 46. 0%) and 65( 26. 2%)were in prefrailty and frailty. The prevalence of prefrailty in 75-85 years old people was significantly higher than that in other groups, and the prevalence of prefrailty and frailty in85 years old people was both higher( χ~2= 45. 247, P<0. 001). In addition, education level( χ~2= 13. 909, P = 0. 008), hypertension( χ~2= 6. 892, P = 0. 032), COPD( χ~2= 8. 411, P =0. 015), cerebral infarction( χ~2= 7. 477, P = 0. 024) and GNRI( χ~2= 22. 942, P = 0. 001)were all the influencing factors of frailty. There were also significant differences in ADL, exercise tolerance and gripping power among the above factors. There were significant differences in cognitive function among subjects with different levels of frailty( χ~2=61. 259, P = 0. 000), ADL( χ~2= 54. 652, P<0. 001), exercise tolerance( χ~2= 77. 001, P =0. 000) and grip strength( χ~2= 54. 778, P < 0. 001). After adjusting for demographic characteristics and chronic diseases such as age, sex, education, BMI, coronary heart disease, hypertension and et al. Logistic regression analysis showed that the OR values of prefrailty, frailty, ADL and exercise tolerance affect cognition are 1. 918( 95% CI 0. 990-3. 716), 2. 732( 95%CI 1. 063-7. 023), 3. 217( 95% CI 1. 421-7. 285), 6. 440( 95% CI1. 803-22. 997).
CONCLUSION
Prefrailty and frailty are closely related to cognitive dysfunction in the elderly.
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No pos
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No neg
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Retriever1325
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Moving from bytes to bedside: a systematic review on the use of artificial intelligence in the intensive care unit.
PURPOSE
Due to the increasing demand for intensive care unit (ICU) treatment, and to improve quality and efficiency of care, there is a need for adequate and efficient clinical decision-making. The advancement of artificial intelligence (AI) technologies has resulted in the development of prediction models, which might aid clinical decision-making. This systematic review seeks to give a contemporary overview of the current maturity of AI in the ICU, the research methods behind these studies, and the risk of bias in these studies.
METHODS
A systematic search was conducted in Embase, Medline, Web of Science Core Collection and Cochrane Central Register of Controlled Trials databases to identify eligible studies. Studies using AI to analyze ICU data were considered eligible. Specifically, the study design, study aim, dataset size, level of validation, level of readiness, and the outcomes of clinical trials were extracted. Risk of bias in individual studies was evaluated by the Prediction model Risk Of Bias ASsessment Tool (PROBAST).
RESULTS
Out of 6455 studies identified through literature search, 494 were included. The most common study design was retrospective [476 studies (96.4% of all studies)] followed by prospective observational [8 (1.6%)] and clinical [10 (2%)] trials. 378 (80.9%) retrospective studies were classified as high risk of bias. No studies were identified that reported on the outcome evaluation of an AI model integrated in routine clinical practice.
CONCLUSION
The vast majority of developed ICU-AI models remain within the testing and prototyping environment; only a handful were actually evaluated in clinical practice. A uniform and structured approach can support the development, safe delivery, and implementation of AI to determine clinical benefit in the ICU.
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No pos
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No neg
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Retriever1326
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Therapeutic SERPINs: Improving on Nature.
Serine proteases drive important physiological processes such as coagulation, fibrinolysis, inflammation and angiogenesis. These proteases are controlled by serine protease inhibitors (SERPINs) that neutralize their activity. Currently, over 1,500 SERPINs are known in nature, but only 37 SERPINs are found in humans. Thirty of these are functional protease inhibitors. The inhibitory potential of SERPINs is in perfect balance with the proteolytic activities of its targets to enable physiological protease activity. Hence, SERPIN deficiency (either qualitative or quantitative) can lead to disease. Several SERPIN resupplementation strategies have been developed to treat SERPIN deficiencies, including concentrates derived from plasma and recombinant SERPINs. SERPINs usually inhibit multiple proteases, but only in their active state. Over the past decades, considerable insights have been acquired in the identification of SERPIN biological functions, their inhibitory mechanisms and specificity determinants. This paves the way for the development of therapeutic SERPINs. Through rational design, the inhibitory properties (selectivity and inhibitory potential) of SERPINs can be reformed and optimized. This review explores the current state of SERPIN engineering with a focus on reactive center loop modifications and backbone stabilization. We will discuss the lessons learned from these recombinant SERPINs and explore novel techniques and strategies that will be essential for the creation and application of the future generation of therapeutic SERPINs.
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No pos
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No neg
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Retriever1327
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Efficacy of pegylated interferon and ribavirin combination therapy for patients with hepatitis C virus infection after curative resection or ablation for hepatocellular carcinoma--A retrospective multicenter study.
The use of pegylated interferon (Peg-IFN) plus ribavirin combination therapy for chronic hepatitis C patients who received curative treatment for hepatocellular carcinoma is controversial. This study tried to clarify this. Ninety-nine chronic hepatitis C patients who received curative resection or radiofrequency ablation for primary hepatocellular carcinoma, met the Milan criteria and were treated with Peg-IFN plus ribavirin therapy were enrolled (75 males, 24 females; mean age, 65.0 ± 5.9 years; 79 HCV genotype 1, 20 genotype 2). Among them, 40 patients who had received curative treatment for a single carcinoma were analyzed for recurrence (observation period: 27.6 ± 18.1 months). The factors associated with recurrence were examined using a log-rank test and a Cox proportional-hazards model. The discontinuation rate of the Peg-IFN plus ribavirin combination therapy was 25% (25/99). Among the patients who completed the therapy, the sustained virologic response rates were 35% for the genotype 1 patients and 56% for the genotype 2 patients. The cumulative incidence rates of recurrence were 10.0% at 1 year and 40.8% at 3 years. On multivariate analysis, a virologic response and platelet counts served as independent factors of recurrence (sustained virologic response, hazard ratio = 0.190, P = 0.029; platelet counts <12 × 10(4) /mm(3), hazard ratio = 3.19, P = 0.019). It is concluded that patients with chronic hepatitis C virus infection after curative treatment for hepatocellular carcinoma can be candidates for anti-viral therapy to reduce the recurrence of hepatocellular carcinoma, especially patients with low platelet counts.
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No pos
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No neg
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Retriever1328
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Staphylococcal alpha-toxin kills human keratinocytes by permeabilizing the plasma membrane for monovalent ions.
Incubation of human keratinocytes with nanomolar concentrations of Staphylococcus aureus alpha-toxin leads to irreversible depletion of cellular ATP. The toxin forms hexamers in the target cell membranes, and rapid transmembrane flux of K+, Na+, and 86Rb+ is observed. Unexpectedly, pores formed in keratinocytes through application of low but lethal doses of alpha-toxin appeared to be considerably smaller than those formed in erythrocyte membranes. They permitted neither rapid influx of Ca2+ or propidium iodide, nor efflux of carboxyfluorescein. Larger pores allowing flux of all three markers did form when the toxin was applied at high concentrations. Flux of monovalent ions and reduction in cellular ATP levels evoked by low toxin doses correlated temporally with a fall in oxygen consumption, which was interpreted to reflect breakdown of mitochondrial respiration. The lethal event could not be thwarted by manipulating the extracellular K+ or Ca2+ concentrations. Realization that alpha-toxin may form very small pores in nucleated cells is important for future research on cellular toxin effects and membrane repair processes.
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No pos
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No neg
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Retriever1329
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TRPs: truly remarkable proteins.
The family of transient receptor potential cation channels has received in the last 10 years a tremendous interest because members of this family are involved in a plethora of cell functions and have been identified as causal for many hereditary and acquired diseases. We shortly introduce these channels, summarize nomenclature and chromosomal location of the 28 mammalian Trp genes, and list the available Trp-deficient mouse lines.
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No pos
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No neg
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Retriever1330
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Clinical profile of people referred to mental health nurses under the Mental Health Nurse Incentive Program.
The Mental Health Nurse Incentive Program (MHNIP) was established in Australia during 2007. The program enables mental health nurses to work in partnership with general practitioners (GPs) in the assessment and treatment of people with severe mental health problems. This paper provides insights into the demographic and clinical profile of 403 people enrolled in the MHNIP in the Ipswich area of Queensland. The clinical presentation (illness severity and symptoms) of those referred to the MHNIP is compared to that of: (i) people referred to a related program known as Access to Allied Psychological Services (ATAPS); and (ii) to clients admitted to acute inpatient care in Queensland. While people referred to the MHNIP presented with more severe problems than those referred to ATAPS, they had less severe problems than those admitted to acute inpatient care. The findings indicate that the MHNIP is meeting the needs of people with complex mental and physical health problems. Further evaluation work is required to determine if the findings from this study can be generalized more broadly. At the national level, consideration should be given to the routine collection of clinical, cost, and demographic data to enable the ongoing monitoring of the program.
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No pos
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No neg
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Retriever1331
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The home environments of children in the United States part I: variations by age, ethnicity, and poverty status.
Although measures of the home environment have gained wide acceptance in the child development literature, what constitutes the "average" or 'typical" home environment in the United States, and how this differs across ethnic groups and poverty status is not known. Item-level data from the National Longitudinal Survey of Youth on four age-related versions of the Home Observation for Measurement of the Environment-Short Form (HOME-SF) from five biennial assessments (1986-1994) were analyzed for the total sample and for four major ethnic groups: European Americans, Asian Americans, African Americans, and Hispanic Americans. The percentages of homes receiving credit on each item of all four versions of the HOME-SF are described. For the majority of items at all four age levels differences between poor and nonpoor families were noted. Differences were also obtained among African American, European American, and Hispanic American families, but the magnitude of the effect for poverty status was greater than for ethnicity, and usually absorbed most of the ethnic group effects on HOME-SF items. For every item at every age, the effects of poverty were proportional across European American, African American, and Hispanic American groups.
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No pos
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No neg
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Retriever1332
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Leiomyoma of the distal oesophagus mimicking achalasia.
An unusual case of a patient with symptoms suggestive of oesophageal achalasia is described. Most oesophageal tumour growths causing secondary achalasia are associated with malignant tumours. This patient had a large oesophageal leiomyoma closely mimicking achalasia. Treatment consisted of oesophagectomy by laparotomy and right-sided thoracotomy. A gastric tube was constructed with a cervical oesophago-gastrostomy. The patient responded well to the treatment and left the hospital after 13 days. Five other cases of benign oesophageal tumours inducing achalasia-like symptoms could be traced. Three of these were leiomyomas.
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No pos
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No neg
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Retriever1333
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Group selection and kin selection: two concepts but one process.
In a recent paper, Traulsen and Nowak use a multilevel selection model to show that cooperation can be favored by group selection in finite populations [Traulsen A, Nowak M (2006) Proc Natl Acad Sci USA 103:10952-10955]. The authors challenge the view that kin selection may be an appropriate interpretation of their results and state that group selection is a distinctive process "that permeates evolutionary processes from the emergence of the first cells to eusociality and the economics of nations." In this paper, we start by addressing Traulsen and Nowak's challenge and demonstrate that all their results can be obtained by an application of kin selection theory. We then extend Traulsen and Nowak's model to life history conditions that have been previously studied. This allows us to highlight the differences and similarities between Traulsen and Nowak's model and typical kin selection models and also to broaden the scope of their results. Our retrospective analyses of Traulsen and Nowak's model illustrate that it is possible to convert group selection models to kin selection models without disturbing the mathematics describing the net effect of selection on cooperation.
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No pos
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No neg
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Retriever1334
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Efficiency in milk production on Reunion Island: dealing with land scarcity.
This paper aims to analyze efficiency on dairy farms in Reunion Island, a French overseas district located in the Indian Ocean. On this island, dairy farming is promoted with financial and technical support from the European Union, with the French and local governments aiming at reducing dependency on imports of milk powder and dairy products and creating employment. A critical factor for increasing the local milk production is the limited availability of arable land because of the small size and the volcanic nature of the island. In this paper, we study the efficiency levels of dairy production on 34 farms by using a data envelopment analysis approach. The average technical efficiency score of farms, assuming constant returns to scale, was 0.927, with 19 out of 34 farms not being efficient. The technical efficiency with a variable returns to scale specification was 0.951. The efficiency with which farmers used their land (subvector efficiencies) was estimated in a second model. The average subvector efficiencies calculated with constant returns to scale and variable returns to scale models were lower than the technical efficiencies. The farmers on the efficiency frontier had a relatively higher milk production, milk production per cow, and land surface than those who were less efficient. A policy promoting better use of the land on inefficient farms should increase the milk production-to-land ratio. Possible on-farm strategies are improved feeding systems, farms having their own heifer breeding, and improved genetics.
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No pos
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No neg
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Retriever1335
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DNA extraction from skins of wild (Hydrochoerus hydrochaeris and Pecari tajacu) and domestic (Sus scrofa domestica) species using a novel protocol.
Sometimes, commercial products obtained from wild animals are sold as if they were from domestic animals and vice versa. At this point of the productive chain, legal control of possible wildlife products is difficult. Common in the commerce of northern Argentina, skins of two wild species, the carpincho and the collared peccary, look very similar to each other and to those of the domestic pig; it is extremely difficult to differentiate them after they have been tanned. Because there was no an adequate methodology to discriminate between leather of these three species, we developed a new methodology of DNA extraction from skin and leather. This new method involves digesting a leather sample using proteinase K, followed by precipitation of proteins with 5 M NaCl, cleaning with absolute isopropanol and DNA precipitation with 70% ethanol. DNA is hydrated in Tris-EDTA buffer. This protocol provided good-quality DNA suitable for analysis with molecular markers. This new protocol has potential for use in identifying leather products of these species using molecular markers based on RAPDs.
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No pos
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No neg
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Retriever1336
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Characterization of i(18p) in prenatal diagnosis by fluorescence in situ hybridization.
A case is presented in which chorionic villus direct preparation and cultured chorionic villus cells revealed a 47,XX+mar karyotype. The marker was a small metacentric chromosome and appeared to be i(18p)--isochromosome 18p. Follow-up studies in both amniotic fluid and fetal fibroblasts confirmed the karyotype. In order to characterize the marker, a panel of biotinylated DNA probes was used, including a whole chromosome 18 probe, chromosome 18-specific alpha satellite DNA, Yac clones, and a pan-telomeric probe. These studies show that the marker is a monocentric i(18p) in which about 80 per cent of chromosome 18 alpha satellite DNA has been lost.
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No pos
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No neg
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Retriever1337
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Evaluation of total IgE in diverse allergosis. Comparative study with other techniques. Part I.
Three hundred patients whose ages ranged between 10 and 50 years were studied. They were classified, according to the number of sensitizing allergens, their sensitization frequency, the clinical syndrome diagnosed, and the therapy followed by each one of them. Intracutaneous tests with twenty-nine groups of allergens and the determination of total IgE, were carried out on each of them. A statistical evaluation was performed on the results obtained, for the purpose of proving mathematically the certainty of these values. The results obtained lead to the following conclusions: 1) The mean values of IGE found coincide with those discovered by other authors, except in the cases of parasytosis and atopic dermatitis. 2) The expression "mean value of IgE" is incorrect for comparative effects with respect to normal levels, since a great diffusion of individual values with respect to this mean value, were observed in all the circumstances studied. 3) A different reaginic response is noticed in the patients studied: from 50 to 70% presented extremely elevated values of serum IgE. Points 1) and 3) are being submitted to an exhaustive re-examination.
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No pos
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No neg
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Retriever1338
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Sialoendoscopic and irrigation findings in chronic obstructive parotitis.
OBJECTIVES/HYPOTHESIS
To study the sialographic changes related to sialoendoscopic and irrigation fluid findings in chronic obstructive parotitis.
STUDY DESIGN
The sialographic changes were classified according to previous studies and related to sialoendoscopic and irrigation fluid findings.
METHODS
This study included 26 patients with a long history of parotid swelling. All patients were examined by radiography and sialography and were diagnosed as having chronic obstructive parotitis without sialolithiasis. Sialoendoscopy was used to observe the ductal system and perform an irrigation treatment. The irrigated liquid was centrifuged, and the fluid deposits were stained and observed using light microscopy.
RESULTS
In all cases, sialoendoscopic examination showed the ductal system was filled with fiber-like substances and hyperemia of the ductal wall. Although a few of the thin and short fiber-like substances were found in the chronic obstructive parotitis patients with sialographic type I and type II changes, many thick and long wadding or lumpy fiber-like substances were revealed in chronic obstructive parotitis patients with sialographic type III and IV changes. Microstones were found in two chronic obstructive parotitis patients with sialographic type III changes, which were stained and identified using light microscopy. Irrigation fluid examination showed that the fiber-like substance was composed of desquamative duct epithelial cells, neutrophils, lymphocytes, and acidophils. Also, some epithelial cells were found in two microliths.
CONCLUSIONS
Sialoendoscopy can provide direct and more detailed observation of the ductal system compared with sialography. Fiber-like substances in the lumen of the ductal system are considered one of the obstructive factors associated with chronic obstructive parotitis.
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No pos
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No neg
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Retriever1339
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Quantitative and qualitative aspects of topoisomerase I and II alpha and beta in untreated and platinum/cyclophosphamide treated malignant ovarian tumors.
Quantitative and qualitative aspects of topoisomerase (Topo) I and II were studied in 17 malignant ovarian tumors [eight untreated and nine after platinum/cyclophosphamide (Pt/Cy) chemotherapy]. Median Topo II catalytic activity was lower (P < 0.05) in tumors after Pt/Cy chemotherapy in comparison to untreated tumors, while no differences were found for Topo I catalytic activity in tumors before and after chemotherapy, as was also found in a previous study (Van der Zee et al. Cancer Res., 51: 5915-5920, 1991). Teniposide (VM-26)-induced cleavable complex formation correlated (r = 0.60; P < 0.05) with Topo II activity, while Topo II decatenation activity was equally but incompletely inhibited by VM-26 in all tumors. No differences were found in Topo II cleavage site patterns in plasmid BR322 DNA for all tumors using an indirect end-labeling procedure. Cleavable complex formation of Topo I by camptothecin (Cpt) did not correlate with Topo I catalytic activity, while Topo I catalytic activity could equally and completely be inhibited by Cpt. By Western blotting, Topo II alpha protein expression was detected in four of eight untreated tumors and three of nine tumors after Pt/Cy chemotherapy, whereas in all tumors a M(r) 150,000 degradation product of Topo II beta was detected. Topo I protein was detected in all tumors at varying levels, but the protein levels did not correlate with Topo I catalytic activity or cleavable complex formation by Cpt. Our study shows that Topo I and II, isolated from human malignant tumors, can be stimulated by Cpt and VM-26, respectively, to induce DNA cleavage, which suggests that topoisomerases are real targets for chemotherapy in patients with ovarian cancer. From in vitro data from the literature it appears that the cleavable complex assay reflects both quantitative and qualitative changes as well as changes in the phosphorylation state of Topo I and II. In combination with the feasibility of the cleavable complex assay for Topo I and II in human malignant tumors, which was found in the present study, it appears that at present the determination of cleavable complex formation by tumors seems to be the most promising parameter of Topo I or II expression in human tumors to be related to response to Topo I- or II-targeted chemotherapy.
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No pos
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No neg
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Retriever1340
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Next-Generation Sequencing Somatic and Germline Assay Troubleshooting Guide Derived From Proficiency Testing Data.
CONTEXT.—
Next-generation sequencing-based assays are increasingly used in clinical molecular laboratories to detect somatic variants in solid tumors and hematologic malignancies and to detect constitutional variants. Proficiency testing data are potential sources of information about challenges in performing these assays.
OBJECTIVE.—
To examine the most common sources of unacceptable results from the College of American Pathologists Next-Generation Sequencing Bioinformatics, Hematological Malignancies, Solid Tumor, and Germline surveys and provide recommendations on how to avoid these pitfalls and improve performance.
DESIGN.—
The College of American Pathologists next-generation sequencing somatic and germline proficiency testing survey results from 2016 to 2019 were analyzed to identify the most common causes of unacceptable results.
RESULTS.—
On somatic and germline proficiency testing surveys, 95.9% (18 815/19 623) and 97.8% (33 890/34 641) of all variants were correctly identified, respectively. The most common causes of unacceptable results related to sequencing were false-negative errors in genomic regions that were difficult to sequence because of high GC content. False-positive errors occurred in the context of homopolymers and pseudogenes. Recurrent errors in variant annotation were seen for dinucleotide and duplication variants and included unacceptable transcript selection and outdated variant nomenclature. A small percentage of preanalytic or postanalytic errors were attributed to specimen swaps and transcription errors.
CONCLUSIONS.—
Laboratories demonstrate overall excellent performance for detecting variants in both somatic and germline proficiency testing surveys. Proficiency testing survey results highlight infrequent, but recurrent, analytic and nonanalytic challenges in performing next- generation sequencing-based assays and point to remedies to help laboratories improve performance.
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No pos
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No neg
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Retriever1341
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Screening of large numbers of Streptococcus pneumoniae isolates for mutations associated with fluoroquinolone resistance using an oligonucleotide probe assay.
Mutations at a relatively small number of sites in parC, parE and gyrA account for most of the fluoroquinolone resistance in Streptococcus pneumoniae clinical isolates. A high throughput oligonucleotide probe assay was developed to screen for mutations in the quinolone-resistance determining region (QRDR) of parC (Ser79), gyrA (Ser81) and parE (Asp435) of Streptococcus pneumoniae. Eight oligonucleotide probes (17mers) were used in the presence of tetramethyl ammonium chloride so that the melting temperature was dependent on length and not on base composition. Using this assay it was possible to accurately detect QRDR mutations from several hundred S. pneumoniae clinical isolates that were grown on nylon membranes.
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No pos
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No neg
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Retriever1342
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Regional blood flow and water content of the obstructed small intestine.
The effects of small-bowel obstruction on the regional distribution of blood flow and water content were studied in a new chronic dog model. Nonstrangulative obstruction was induced 40 cm proximal to the canine ileocolic valve. Blood flow was measured with 15-micron microspheres and hemodynamic and respiratory values were recorded before (experimental phase I) and five days after (experimental phase II) the induction of the obstruction. Two separate control groups of dogs were studied: baseline controls and sham-operative groups (phases I and II). Hemodynamic and respiratory values were stable in both phases in all groups. A comparison of sham phase-II data with the experimental phase-II data in the 120-cm segment of bowel proximal to the site of obstruction showed an 85% increase in blood flow (range, 49% to 106%); for the 280 cm of bowel proximal to the site of obstruction, there was a 6% increase in water content (range, 5% to 9%), and a 39% decrease in dry bowel weight (range, 34% to 46%). These findings help illustrate the pathophysiologic characteristics of microvascular changes in bowel obstruction, which are likely to have particular clinical significance for patients with cardiopulmonary diseases.
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No pos
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No neg
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Retriever1343
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Expression of a hepatitis A virus antigen in Lactococcus lactis and Escherichia coli and evaluation of its immunogenicity.
An epidemic shift in Hepatitis A virus (HAV) infection has been observed in recent years in rapidly developing countries, with increasing numbers of severe adult cases which has led to renewed interest in vaccination. Our approach in vaccine development uses recombinant expression of the highly immunogenic HAV antigen VP1-P2a in food-grade lactic acid bacterium Lactococcus lactis and in Escherichia coli. We used genetic constructs that enable nisin-controlled expression of the antigen in L. lactis in three different forms: (a) intracellularly, (b) on the bacterial surface and (c) on the bacterial surface fused with the fragment of the E. coli flagellin molecule that can act as a molecular adjuvant. Expression of the two surface forms of the antigen was achieved in L. lactis, and the resulting antigen-displaying bacteria were administered orally to mice. Half the animals in each of the two groups developed specific IgGs, with titers increasing over time and reaching 1:422 without flagellin and 1:320 with flagellin. A much higher titer 1:25,803 was observed with the parenterally administered antigen, which was purified from E. coli. With the latter, a significant mucosal IgA response was also observed. Despite significant titers, the IgGs elicited with oral or parenteral administration could not prevent HAV from infecting cells in a virus neutralization assay, suggesting that the antibodies cannot recognize viral surface epitopes. Nevertheless, orally administered HAV antigen expressed in L. lactis elicited significant systemic humoral immune response showing the feasibility for development of effective HAV vaccine for mucosal delivery.
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No pos
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No neg
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Retriever1344
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Europium chelate-loaded liposomes: a tool for the study of binding and integrity of liposomes.
Using the biotin-streptavidin interaction as a model, we investigated the suitability of lanthanide chelates as encapsulated liposomal labels in liposome-based binding assays. Large unilamellar phospholipid:cholesterol liposomes containing europium-DTPA chelate and biotinylated phosphatidylethanolamine were prepared by detergent dialysis. The resulting Eu-liposomes ([symbol: see text] 120 nm) bound specifically to streptavidin in microtiter wells as measured by time-resolved fluorometric assay (TRF). The intensity of fluorescence released from the bound liposomes was dependent on the concentration of biotin in the liposome membrane, the concentration of europium entrapped in the liposomes, the incubation time and the amount of liposomes used in the assay. The sensitivity of the TRF assay allowed the detection of binding of attomole quantities of liposomes. The streptavidin-immobilised liposomes subjected to porcine pancreatic phospholipase A2 (EC 3.1.1.4) and detergents displayed a dose-dependent release of the encapsulated europium. Lanthanide-chelate-liposomes should prove useful for studies addressing binding and stability of liposomes.
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No pos
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No neg
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Retriever1345
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Genome-Wide Identification of DNA Methylases and Demethylases in Kiwifruit (Actinidia chinensis).
DNA methylation plays an important role in a wide range of developmental and physiological processes in plants. It is primarily catalyzed and regulated by cytosine-5 DNA methyltransferases (C5-MTases) and a group of DNA glycosylases that act as demethylases. To date, no genome-scale analysis of the two kiwifruit (Actinidia chinensis) families has been undertaken. In our study, nine C5-MTases and seven DNA demethylase genes were identified in the kiwifruit genome. Through selective evolution analysis, we found that there were gene duplications in C5-MTases and demethylases, which may have arisen during three genome doubling events followed by selection during evolution of kiwifruit. Expression analysis of DNA methylases (C5-MTases) and demethylases identified changes in transcripts of DNA methylation and demethylation genes during both vegetative and reproductive development. Moreover, we found that some members of the two methylase/demethylase families may also be involved in fruit ripening and the regulation of softening. Our results help to better understand the complex roles of methylation/demethylation in plants and provide a foundation for analyzing the role of DNA methylation modification in kiwifruit growth, development and ripening.
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No pos
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No neg
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Retriever1346
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Hybrid Plasma-Liquid Functionalisation for the Enhanced Stability of CNT Nanofluids for Application in Solar Energy Conversion.
Macroscopic ribbon-like assemblies of carbon nanotubes (CNTs) are functionalised using a simple direct-current-based plasma-liquid system, with oxygen and nitrogen functional groups being added. These modifications have been shown to reduce the contact angle of the ribbons, with the greatest reduction being from 84° to 35°. The ability to improve the wettability of the CNTs is of paramount importance for producing nanofluids, with relevance for a number of applications. Here, in particular, we investigate the efficacy of these samples as nanofluid additives for solar-thermal harvesting. Surface treatments by plasma-induced non-equilibrium electrochemistry are shown to enhance the stability of the nanofluids, allowing for full redispersion under simulated operating conditions. Furthermore, the enhanced dispersibility results in both a larger absorption coefficient and an improved thermal profile under solar simulation.
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No pos
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No neg
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Retriever1347
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Impact of a 3-Day Introductory Oncology Course on First-Year International Medical Students.
Although only some medical students will choose cancer as their specialty, it is essential that all students have a basic understanding of cancer and its treatment. The purpose of this study was to evaluate the impact of an introductory clinical oncology course on first-year international medical students. Evaluation of the course involved a quantitative survey designed for this study that was given pre- and post-course completion. Participants included 29 first-year international medical students. Students reported that the course affected them emotionally more than they anticipated it would prior to beginning the course. By the end of the course, students felt more comfortable focusing on how to live with cancer, felt less afraid of dealing with death, and were better able to cope with uncomfortable emotional situations. The course had no significant effect on students' interest in specializing in oncology in the future. Our study provides evidence that an introductory oncology course can increase student comfort with issues related to living with cancer, with confronting and dealing with death and dying, and with coping with uncomfortable emotional situations as related to cancer care. In anticipation of growing shortages in oncology specialists in the coming years, the ability of an early course in oncology to attract more students to the field is of interest. Future research should examine ethnic and cultural differences in uptake of the clinical oncology courses across continents and should use direct observation in addition to self-report in evaluating outcomes.
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No pos
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No neg
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Retriever1348
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[Urinary tract hemangiopericytoma treated with radical surgery and neoadjuvant chemotherapy. Report of two cases.]
OBJECTIVE
Hemangiopericytoma is a tumor of vascular origin. It is very rare in the prostate. They are generally aggressive tumors. Currently, the treatment of choice is radical surgery. In the literature, there are less than 50 cases described, and neoadjuvant treatment has not been reported in any article. This treatment presents positive responses in another type of sarcomas. Our goal is to report two cases of malignant hemangiopericytoma. The first case was treated with radical surgery and the second case was treated with neoadjuvant chemotherapy before surgery.
METHODS
The first case is a 40 year old male. Obstructive urinary symptoms were his first symptoms. A prostate mass with tumor characteristics was seen on ultrasound. After transrectal biopsy, he was diagnosed with hemangiopericitoma. Because the tumor size, neoadjuvant chemotherapeutic prior to radical surgery was decided. The second case is a 77 year old male with an incidental diagnosis of renal mass. After radical nephrectomy, he was diagnosed with hemangiopericitoma. He did not receive adjuvant chemotherapy.
RESULTS
In the first case, after neoadjuvant therapy, tumor size was reduced significantly. A pelvic exenteration with radical cystoprostatectomy and rectal resection and Bricker type urinary diversion and colostomy were carried out. In the second case controls after radical nephrectomy were correct and he did not need any treatment.
CONCLUSIONS
In urinary tumors, the prostate hemangiopericytoma is a rare entity. Currently, neoadjuvant chemotherapy is not established as treatment for these tumors. For other sarcomas neoadyuvant treatment has good response. In our case, a good result was obtained with neoadjuvant chemotheraphy before surgery. However, a greater number of cases are necessary to establish the use of neoadjuvant chemotherapy in urinary hemangiopericytomas.
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No pos
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No neg
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Retriever1349
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Effects of atropine and L-NAME on cutaneous blood flow during body heating in humans.
We sought to investigate further the roles of sweating, ACh spillover, and nitric oxide (NO) in the neurally mediated cutaneous vasodilation during body heating in humans. Six subjects were heated with a water-perfused suit while cutaneous blood flow was measured with a laser-Doppler flowmeter. After a rise in core temperature (1. 0 +/- 0.1 degrees C) and the establishment of cutaneous vasodilation, atropine and subsequently the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) were given to the forearm via a brachial artery catheter. After atropine infusion, cutaneous vascular conductance (CVC) remained constant in five of six subjects, whereas L-NAME administration blunted the rise in CVC in three of six subjects. A subsequent set of studies using intradermal microdialysis probes to selectively deliver drugs into forearm skin confirmed that atropine did not affect CVC. However, perfusion of L-NAME resulted in a significant decrease in CVC (37 +/- 4%, P < 0.05). The results indicate that neither sweating nor NO release via muscarinic receptor activation is essential to sustain cutaneous dilation during heating in humans.
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No pos
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No neg
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Retriever1350
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Hypothermia as a neuroprotective strategy in subarachnoid hemorrhage: a pathophysiological review focusing on the acute phase.
Aneurysmal subarachnoid hemorrhage (SAH) remains a very prevalent challenge in neurosurgery associated with a high morbidity and mortality due to the lack of specific treatment modalities. The prognosis of SAH patients depends primarily on three factors: (i) the severity of the initial bleed, (ii) the endovascular or neurosurgical procedure to occlude the aneurysm and (iii) the occurrence of late sequelae, namely delayed ischemic neurological deficits due to cerebral vasospasm. While neurosurgeons and interventionalists have put significant efforts in minimizing periprocedural complications and a multitude of investigators have been devoted to the research on chronic vasospasm, the acute phase of SAH has not been studied in comparable detail. In various experimental studies during the past decade, hypothermia has been shown to reduce neuronal damage after ischemia, traumatic brain injury and other cerebrovascular diseases. Clinically, only some of these encouraging results could be reproduced. This review analyses results of studies on the effects of hypothermia on SAH with special respect to the acute phase in an experimental setting. Based on the available data, some considerations for the application of mild to moderate hypothermia in patients with subarachnoid hemorrhage are given.
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No pos
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No neg
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Retriever1351
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Hepatic fibrogenesis requires sympathetic neurotransmitters.
BACKGROUND AND AIMS
Hepatic stellate cells (HSC) are activated by liver injury to become proliferative fibrogenic myofibroblasts. This process may be regulated by the sympathetic nervous system (SNS) but the mechanisms involved are unclear.
METHODS
We studied cultured HSC and intact mice with liver injury to test the hypothesis that HSC respond to and produce SNS neurotransmitters to promote fibrogenesis.
RESULTS
HSC expressed adrenoceptors, catecholamine biosynthetic enzymes, released norepinephrine (NE), and were growth inhibited by alpha- and beta-adrenoceptor antagonists. HSC from dopamine beta-hydroxylase deficient (Dbh(-/-)) mice, which cannot make NE, grew poorly in culture and were rescued by NE. Inhibitor studies demonstrated that this effect was mediated via G protein coupled adrenoceptors, mitogen activated kinases, and phosphatidylinositol 3-kinase. Injury related fibrogenic responses were inhibited in Dbh(-/-) mice, as evidenced by reduced hepatic accumulation of alpha-smooth muscle actin(+ve) HSC and decreased induction of transforming growth factor beta1 (TGF-beta1) and collagen. Treatment with isoprenaline rescued HSC activation. HSC were also reduced in leptin deficient ob/ob mice which have reduced NE levels and are resistant to hepatic fibrosis. Treating ob/ob mice with NE induced HSC proliferation, upregulated hepatic TGF-beta1 and collagen, and increased liver fibrosis.
CONCLUSIONS
HSC are hepatic neuroglia that produce and respond to SNS neurotransmitters to promote hepatic fibrosis.
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No pos
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No neg
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Retriever1352
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Allogeneic adipose-derived stem cell transplantation on knee osteoarthritis rats and its effect on MMP-13 and DDR2.
This study investigated the efficacy of transplantation of allogeneic adipose-derived stem cells (ADMSCs) in rats with knee osteoarthritis (KOA) and the effect on the expression of matrix metalloproteinase 13 (MMP-13) and discoid domain receptor 2 (DDR2). In total, sixty rats were randomly selected. Eleven rats were selected as the blank group. Forty-four rat KOA models were established, and the remaining 5 rats were used for stem cell extraction. The rats were randomly divided into two groups, and the transplantation group was treated with ADMSCs transplantation. The KOA group was intragastrically administered with saline. The expressions of MMP-13 mRNA and DDR2 in rats were detected by RT-qPCR and immunohistochemistry. Correlation analysis was performed in MMP-13 mRNA and DDR2 expression levels in the KOA rats. After treatment, the indexes of Lequesne MG knee joints, MMP-13 mRNA and DDR2 in the transplanted rats were significantly lower than those in the KOA group (P<0.05). In the KOA rats, MMP-13 mRNA and DDR2 was positively correlated (r=0.830, P<0.001). Therefore, the transplantation of ADMSCs has a significant effect on the KOA rats, which can effectively improve the knee joint function of KOA rats and reduce the expression of MMP-13 mRNA and DDR2 in rats, and it is worthy of clinical promotion.
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No pos
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No neg
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Retriever1353
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NPS 1506 attenuates cognitive dysfunction and hippocampal neuron death following brain trauma in the rat.
Although several noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonists have been shown to be substantially efficacious in experimental models of brain trauma, side effects associated with this class of compounds have impeded clinical application. Therefore, new noncompetitive NMDA receptor antagonists have been developed, including NPS 1506, that appear to be nontoxic but retain efficacy. In the present study, we evaluated the efficacy of NPS 1506 in a model of parasagittal fluid percussion brain trauma in the anesthetized rat. Administration of 1 mg/kg NPS 1506 at both 10 min and 4 h posttrauma induced no changes in brain temperature, mean arterial pressure, pulse, or arterial blood gasses. At 1 week postinjury, animals treated with the same dosing regimen of NPS 1506 demonstrated a dramatic attenuation of memory dysfunction evaluated by a water maze task (P < 0.02) and had greatly reduced neuron death in the CA3 subfield of the hippocampus (P < 0.01). However, NPS 1506 treatment did not significantly affect the extent of cortical tissue loss following injury. Since memory dysfunction and hippocampal damage are common and potentially related consequences of brain trauma in humans, our results suggest that NPS 1506 treatment may have clinical utility.
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No pos
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No neg
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Retriever1354
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Rapid contrasting of extracellular elements in thin sections.
Standard methods for contrasting ultrathin sections generally have their greatest effect on cells and cellular components, whereas extracellular elements remain relatively electron-lucent. Occasionally, some extracellular elements even fail completely to react with the staining solutions. We describe a method for rendering a uniformly high contrast to extracellular tissue components. This consists of a brief prestaining of grids with diluted tannic acid in distilled water. Simple, rapid, and versatile, this procedure can be routinely applied to all tissue samples examined by electron microscopy. As an additional advantage, the method greatly enhances the electron density of intracellular glycogen. Higher concentrations of tannic acid give increased electron density, especially to elastin, and can therefore be used as an elastin stain.
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No pos
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No neg
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Retriever1355
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What's new in wound treatment: a critical appraisal.
With the growing demand for the specialized care of wounds, there is an ever expanding abundance of wound care modalities available. It is difficult to identify which products or devices enhance wound healing, and thus, a critical and continual look at new advances is necessary. The goal of any wound regimen should be to optimize wound healing by combining basic wound care modalities including debridement, off-loading, and infection control with the addition of advanced therapies when necessary. This review takes a closer look at current uses of negative pressure wound therapy, bioengineered alternative tissues, and amniotic membrane products. While robust literature may be lacking, current wound care advances are showing great promise in wound healing.
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No pos
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No neg
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Retriever1356
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Three explanations for biodiversity hotspots: small range size, geographical overlap and time for species accumulation. An Australian case study.
To understand the generation and maintenance of biodiversity hotspots, we tested three major hypotheses: rates of diversification, ecological limits to diversity, and time for species accumulation. Using dated molecular phylogenies, measures of species' range size and geographical clade overlap, niche modelling, and lineages-through-time plots of Australian Fabaceae, we compared the southwest Australia Floristic Region (SWAFR; a global biodiversity hotspot) with a latitudinally equivalent non-hotspot, southeast Australia (SEA). Ranges of species (real and simulated) were smaller in the SWAFR than in SEA. Geographical overlap of clades was significantly greater for Daviesia in the SWAFR than in SEA, but the inverse for Bossiaea. Lineage diversification rates over the past 10 Myr did not differ between the SWAFR and SEA in either genus. Interaction of multiple factors probably explains the differences in measured diversity between the two regions. Steeper climatic gradients in the SWAFR probably explain the smaller geographical ranges of both genera there. Greater geographical overlap of clades in the SWAFR, combined with a longer time in the region, can explain why Daviesia is far more species-rich there than in SEA. Our results indicate that the time for speciation and ecological limits hypotheses, in concert, can explain the differences in biodiversity.
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No pos
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No neg
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Retriever1357
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The effect of four different irrigation systems in the removal of a root canal sealer.
OBJECTIVES
The aim of this study was to compare the efficiency of sonic, ultrasonic, and hydrodynamic devices in the removal of a root canal sealer from the surface and from simulated irregularities of root canals.
MATERIALS AND METHODS
Fifty-three root canals with two standardized grooves in the apical and coronal parts of longitudinally split roots were covered with AH Plus root canal sealer. Compared were the effects of (control) syringe irrigation, (1) CanalBrush, (2) passive ultrasonic irrigation, (3) EndoActivator, and (4) RinsEndo on the removal of the sealer. The specimens were divided into four groups (N = 12) and one control group (N = 5) via randomization. The amount of remaining sealer in the root canal irregularities was evaluated under a microscope using a 4-grade scoring system, whereas the remaining sealer on the root canal surface was evaluated with a 7-grade scoring system.
RESULTS
Passive ultrasonic irrigation is more effective than the other tested irrigation systems or syringe irrigation in removing sealer from root canal walls (p < 0.01). None of the techniques had a significant effect on cleaning the lateral grooves.
CONCLUSIONS
Within the limitations of this study protocol ultrasonic irrigation shows a superior effect on sealer removal from the root canal surface during endodontic retreatment. Cleaning of lateral grooves seems not to be possible with one of the techniques investigated.
CLINICAL RELEVANCE
Incomplete removal of root canal sealer during re-treatment may cause treatment failure. Passive Ultrasonic irrigation seems to be the most effective system to remove sealer from a root canal.
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No pos
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No neg
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Retriever1358
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Wean Earlier and Automatically with New technology (the WEAN study): a protocol of a multicentre, pilot randomized controlled trial.
BACKGROUND
Weaning is the process during which mechanical ventilation is withdrawn and the work of breathing is transferred from the ventilator back to the patient. Prolonged weaning is associated with development of ventilator-related complications and longer stays in the Intensive Care Unit (ICU). Computerized or Automated Weaning is a novel weaning strategy that continuously measures and adapts ventilator support (by frequently measuring and averaging three breathing parameters) and automatically conducts Spontaneous Breathing Trials to ascertain whether patients can resume autonomous breathing. Automated Weaning holds promise as a strategy to reduce the time spent on the ventilator, decrease ICU length of stay, and improve clinically important outcomes.
METHODS/DESIGN
A pilot weaning randomized controlled trial (RCT) is underway in the ICUs of 8 Canadian hospitals. We will randomize 90 critically ill adults requiring invasive ventilation for at least 24 hours and identified at an early stage of the weaning process to either Automated Weaning (SmartCare) or Protocolized Weaning. The results of a National Weaning Survey informed the design of the Protocolized Weaning arm. Both weaning protocols are operationalized in Pressure Support mode, include opportunities for Spontaneous Breathing Trials, and share a common sedation protocol, oxygen titration parameters, and extubation and reintubation criteria. The primary outcome of the WEAN study is to evaluate compliance with the proposed weaning and sedation protocols. A key secondary outcome of the pilot RCT is to evaluate clinician acceptance of the weaning and sedation protocols. Prior to initiating the WEAN Study, we conducted a run-in phase, involving two patients per centre (randomizing the first participant to either weaning strategy and assigning the second patient to the alternate strategy) to ensure that participating centres could implement the weaning and sedation protocols and complete the detailed case report forms.
DISCUSSION
Mechanical ventilation studies are difficult to implement; requiring protocols to be operationalized continuously and entailing detailed daily data collection. As the first multicentre weaning RCT in Canada, the WEAN Study seeks to determine the feasibility of conducting a large scale future weaning trial and to establish a collaborative network of ICU clinicians dedicated to advancing the science of weaning.
TRIAL REGISTRATION NUMBER
ISRCTN43760151.
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No pos
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No neg
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Retriever1359
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Stepwise deprotonation of sumanene: electronic structures, energetics and aromaticity alterations.
The first comprehensive theoretical investigation of structural, energetic, and electronic changes in a sumanene skeleton, C21H12, upon a step-wise deprotonation process is performed. This study is complemented by a detailed consideration of aromaticity in target bowl-shaped systems, including neutral sumanene and its three deprotonated anions, namely C21H111-, C21H102-, and C21H93-. In order to obtain the most reliable and method-independent characteristics, a set of aromatic descriptors of different nature has been applied. It included structure-based HOMA, topological descriptors PDI and FLU, as well as magnetic NICS and ACID. The calculation results reveal that the neutral sumanene can be best described as mechanically bent triphenylene, in which π-conjugation is mostly localized over three peripheral 6-membered rings. Sequential deprotonation changed the system from the localized mono-anionic to semi-localized di-anionic, and eventually to the fully delocalized tri-anionic sumanenyl species. Structural changes, namely, bond equalization upon the deprotonation process, are in excellent agreement with alterations observed in electronic structures and aromaticity. Deprotonation results in a significant reduction of the barrier for a bowl-to-bowl transition only in the tri-anionic sumanenyl system, whereas the first and the second deprotonation steps show no notable effect. This clearly indicates that only complete aromatization of the sumanene core in C21H93- leads to a substantial increase of bowl flexibility.
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No pos
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No neg
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Retriever1360
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Nine children over the age of one year with full trisomy 13: a case series describing medical conditions.
Trisomy 13 (Patau syndrome), identified by Patau and colleagues [1960; Lancet 1: 790-793] is the third most common autosomal condition. Population studies indicate less than one in 10 children reaches their first birthday. In the face of mixed findings and recommendations for treatment, additional research is needed to further determine what contributes to longevity and implications for treatment for presenting medical conditions. The purpose of the present study is to report on presenting medical conditions and the presence or absence of the specific conditions (age at survey completion). Data on nine survivors (seven female, two male) with trisomy 13 indicated mean gestational age of approximately 36 weeks, birth weight ranging from 1100 to 3290 g and mean length of 45.3 cm. Length of hospital stay after birth varied. The majority of infants presented with well-known physical characteristics. Medical conditions and their treatment varied at birth and at survey completion. Notably, several infants' cardiac anomalies resolved without surgical intervention. Surgeries were provided for a range of conditions including gastrostomy tube placement to address feeding issues and removal of intestinal blockage. There were no reports of holoprosencephaly. Implications and recommendations are provided.
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No pos
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No neg
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Retriever1361
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The use of surface-enhanced Raman scattering for detecting molecular evidence of life in rocks, sediments, and sedimentary deposits.
Raman spectroscopy is a versatile analytical technique capable of characterizing the composition of both inorganic and organic materials. Consequently, it is frequently suggested as a payload on many planetary landers. Only approximately 1 in every 10(6) photons are Raman scattered; therefore, the detection of trace quantities of an analyte dispersed in a sample matrix can be much harder to achieve. To overcome this, surface-enhanced Raman scattering (SERS) and surface-enhanced resonance Raman scattering (SERRS) both provide greatly enhanced signals (enhancements between 10(5) and 10(9)) through the analyte's interaction with the locally generated surface plasmons, which occur at a "roughened" or nanostructured metallic surface (e.g., Cu, Au, and Ag). Both SERS and SERRS may therefore provide a viable technique for trace analysis of samples. In this paper, we describe the development of SERS assays for analyzing trace amounts of compounds present in the solvent extracts of sedimentary deposits. These assays were used to detect biological pigments present in an Arctic microoasis (a small locale of elevated biological productivity) and its detrital regolith, characterize the pigmentation of microbial mats around hydrothermal springs, and detect fossil organic matter in hydrothermal deposits. These field study examples demonstrate that SERS technology is sufficiently mature to be applied to many astrobiological analog studies on Earth. Many current and proposed imaging systems intended for remote deployment already posses the instrumental components needed for SERS. The addition of wet chemistry sample processing facilities to these instruments could yield field-deployable analytical instruments with a broadened analytical window for detecting organic compounds with a biological or geological origin.
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No pos
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No neg
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Retriever1362
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Tumour suppressor microRNAs contribute to drug resistance in malignant pleural mesothelioma by targeting anti-apoptotic pathways.
Aim: Aberrant microRNA expression is a common event in cancer drug resistance, however its involvement in malignant pleural mesothelioma (MPM) drug resistance is largely unexplored. We aimed to investigate the contribution of microRNAs to the resistance to drugs commonly used in the treatment of MPM. Methods: Drug resistant MPM cell lines were generated by treatment with cisplatin, gemcitabine or vinorelbine. Expression of microRNAs was quantified using RT-qPCR. Apoptosis and drug sensitivity assays were carried out following transfection with microRNA mimics or BCL2 siRNAs combined with drugs. Results: Expression of miR-15a, miR-16 and miR-34a was downregulated in MPM cells with acquired drug resistance. Transfection with miR-15a or miR-16 mimics reversed the resistance to cisplatin, gemcitabine or vinorelbine, whereas miR-34a reversed cisplatin and vinorelbine resistance only. Similarly, in parental cell lines, miR-15a or miR-16 mimics sensitised cells to all drugs, whereas miR-34a increased response to cisplatin and vinorelbine. Increased microRNA expression increased drug-induced apoptosis and caused BCL2 mRNA and protein reduction. RNAi-mediated knockdown of BCL2 partly recapitulated the increase in drug sensitivity in cisplatin and vinorelbine treated cells. Conclusion: Drug-resistant MPM cell lines exhibited reduced expression of tumour suppressor microRNAs. Increasing tumour suppressor of microRNA expression sensitised both drug resistant and parental cell lines to chemotherapeutic agents, in part through targeting of BCL2. Taken together, these data suggest that miR-15a, miR-16 and miR-34a are involved in the acquired and intrinsic drug resistance phenotype of MPM cells.
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No pos
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No neg
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Retriever1363
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Autonomy and care: respecting the wishes of the deceased patient.
In previous articles it has been established that a duty of care is owed to all those for whom we care, a duty not to cause harm, to continuously aim to provide the best possible care and treatment, to act at all times in the best interests of those for whom we care. This includes respecting the autonomous choices made by the person regarding the treatment of their body. Autonomy is the capacity to think, decide and act on the basis of such thought and decision, freely and independently (Gillon, 1986), in other words, deliberated self-rule.
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No pos
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No neg
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Retriever1364
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Leiomyosarcoma of scrotum--case report and review of literature.
Leiomyosarcoma of the scrotum is a rare tumor. Cutaneous and subcutaneous leiomyosarcomas constitute the two subtypes. We report a case of cutaneous leiomyosarcoma of the scrotum in a 73-year-old man. Cutaneous leiomyosarcoma arises from the smooth muscle of the dartos or arrectores pilorum. It is often mistaken for a benign lesion. We describe the clinical and pathologic features and review the published reports of this uncommon malignancy. It is best treated by wide local excision. Inguinal lymph node dissection is not advocated, unless a high degree of suspicion is present for lymph node metastasis. Long-term follow-up is essential, because of the risk of delayed local recurrence and distant metastasis.
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No pos
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No neg
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Retriever1365
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Role of angiotensin receptors in the medial amygdaloid nucleus in autonomic, baroreflex and cardiovascular changes evoked by chronic stress in rats.
This study investigated the role of AT1 , AT2 and Mas angiotensinergic receptors within the MeA in autonomic, cardiovascular and baroreflex changes evoked by a 10-day (1 hr daily) repeated restraint stress (RRS) protocol. Analysis of cardiovascular function after the end of the RRS protocol indicated increased values of arterial pressure, without heart rate changes. Arterial pressure increase was not affected by acute MeA treatment after the RRS with either the selective AT1 receptor antagonist losartan, the selective AT2 receptor antagonist PD123319 or the selective Mas receptor antagonist A-779. Analysis of heart rate variability indicated that RRS increased the sympathetic tone to the heart, which was inhibited by MeA treatment with either losartan, PD123319 or A-779. Baroreflex function assessed using the pharmacological approach via intravenous infusion of vasoactive agents revealed a facilitation of tachycardia evoked by blood pressure decrease in chronically stressed animals, which was inhibited by MeA treatment with losartan. Conversely, baroreflex responses during spontaneous fluctuations of blood pressure were impaired by RRS, and this effect was not affected by injection of the angiotensinergic receptor antagonists into the MeA. Altogether, the data reported in the present study suggest an involvement of both angiotensinergic receptors present in the MeA in autonomic imbalance evoked by RRS, as well as an involvement of MeA AT1 receptor in the enhanced baroreflex responses during full range of blood pressure changes. Results also indicate that RRS-evoked increase in arterial pressure and impairment of baroreflex responses during spontaneous variations of arterial pressure are independent of MeA angiotensinergic receptors.
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No pos
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No neg
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Retriever1366
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Structure of the Qbeta replicase, an RNA-dependent RNA polymerase consisting of viral and host proteins.
The RNA-dependent RNA polymerase core complex formed upon infection of Escherichia coli by the bacteriophage Qbeta is composed of the viral catalytic beta-subunit as well as the host translation elongation factors EF-Tu and EF-Ts, which are required for initiation of RNA replication. We have determined the crystal structure of the complex between the beta-subunit and the two host proteins to 2.5-A resolution. Whereas the basic catalytic machinery in the viral subunit appears similar to other RNA-dependent RNA polymerases, a unique C-terminal region of the beta-subunit engages in extensive interactions with EF-Tu and may contribute to the separation of the transient duplex formed between the template and the nascent product to allow exponential amplification of the phage genome. The evolution of resistance by the host appears to be impaired because of the interactions of the beta-subunit with parts of EF-Tu essential in recognition of aminoacyl-tRNA.
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No pos
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No neg
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Retriever1367
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The effect of parathion-methyl and antidotes on parotid and pancreatic glands: a pilot experimental study.
The objective of this study is to investigate the functions of parotid and pancreatic glands in response to intoxication with parathion-methyl (PM) and the effects of treatment in rats. Seventy-five male Wistar rats were divided equally into five groups: Group I, control; group II, received atropine and pralidoxime (2-PAM) for 24 h, but no PM; group III, oral PM but no atropine and 2-PAM; group IV, PM and atropine for 24 h and 2-PAM; group V, PM and atropine for 96 h and 2-PAM. After the administration of the chemicals, blood samples were drawn to test for amylase, lipase, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE), while pancreatic and parotid glands of each rat were removed for light microscopic examination. Amylase levels were found significantly elevated in groups II, III, IV, and V, whereas lipase levels were supranormal in groups III, IV, and V. The blood levels of AChE were decreased in groups III and IV and BChE were decreased in II, III, IV, and V. No evidence of pancreatitis and parotitis was identified in the histopathologic evaluation in any group in 96 h; however, hyperchromasia, irregularity in nuclei, and binuclear cells were observed in all parotid glands in group V. Parotitis and pancreatitis were not evident; however, hyperamylasemia and hyperlipasemia were found, whereas various histologic changes in parotid glands were documented in the groups that were administered organophosphate and treatment.
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No pos
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No neg
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Retriever1368
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A single expression site with a conserved leader sequence regulates variation of expression of the Pneumocystis carinii family of major surface glycoprotein genes.
The major surface glycoprotein (MSG) of Pneumocystis carinii is encoded by a family of related but distinct genes distributed throughout the P. carinii genome. Previous reports of the genomic and mRNA MSG structure suggested that there was a highly conserved 5'-untranslated region and a highly variable translated region. In the current study, we demonstrate that there is a single expression site for MSG expression and that different MSG genes are located downstream of this expression site. Isolation of a genomic clone containing the putative 5'-untranslated region has demonstrated that there was a single base sequencing error in what was considered to be the untranslated region. The corrected sequence reveals an extended open reading frame encoding a constant amino-terminal leader domain, with a typical signal peptide, for the MSG protein family. Since this constant amino-terminal domain is encoded by a single copy genomic sequence, a recombination/gene conversion-mediated antigenic switching event is required to effect the known variability in expressed MSG sequences. Therefore, like some bacterial and protozoan pathogens, the opportunistic fungal pathogen P. carinii contains a constant genomic site dedicated to MSG expression and a switchable downstream region for the variable part of the MSG gene family.
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No pos
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No neg
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Retriever1369
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Detecting parent of origin and dominant QTL in a two-generation commercial poultry pedigree using variance component methodology.
INTRODUCTION
Variance component QTL methodology was used to analyse three candidate regions on chicken chromosomes 1, 4 and 5 for dominant and parent-of-origin QTL effects. Data were available for bodyweight and conformation score measured at 40 days from a two-generation commercial broiler dam line. One hundred dams were nested in 46 sires with phenotypes and genotypes on 2708 offspring. Linear models were constructed to simultaneously estimate fixed, polygenic and QTL effects. Different genetic models were compared using likelihood ratio test statistics derived from the comparison of full with reduced or null models. Empirical thresholds were derived by permutation analysis.
RESULTS
Dominant QTL were found for bodyweight on chicken chromosome 4 and for bodyweight and conformation score on chicken chromosome 5. Suggestive evidence for a maternally expressed QTL for bodyweight and conformation score was found on chromosome 1 in a region corresponding to orthologous imprinted regions in the human and mouse.
CONCLUSION
Initial results suggest that variance component analysis can be applied within commercial populations for the direct detection of segregating dominant and parent of origin effects.
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No pos
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No neg
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Retriever1370
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Alcohol Use Disorder Criteria Exhibit Different Comorbidity Patterns.
BACKGROUND AND AIMS
Alcohol use disorder is comorbid with numerous other forms of psychopathology, including externalizing disorders (e.g., conduct disorder) and, to a lesser extent, internalizing conditions (e.g., depression, anxiety). Much of the time, overlap among alcohol use disorder and other conditions is explored at the disorder-level, assuming that criteria are co-equal indicators of other psychopathology even though alcohol use disorder criteria span numerous varied domains. Emerging evidence suggests that there are symptom clusters within the construct of alcohol use disorder that relate differentially with important external criteria, including psychopathology and allied personality traits (e.g., impulsivity, novelty seeking). The present study mapped individual alcohol use disorder criteria onto internalizing and externalizing dimensions. Design and participants We used multivariate and factor analytic modeling and data from 2 large nationally representative samples of past year drinkers (ns = 25,604; 19,454).
SETTING
USA MEASUREMENTS: Psychopathology was assessed using the Alcohol Use Disorder and Associated Disabilities Interview Schedule, yielding alcohol use disorder criteria, internalizing diagnoses (i.e., major depressive disorder, dysthymia, social anxiety disorder, generalized anxiety disorder, specific phobia, agoraphobia, and panic disorder), and externalizing diagnoses and symptoms (i.e., antisocial personality disorder, conduct disorder, and 3 impulsivity items drawn from borderline personality disorder criteria). Alcohol consumption was assessed in terms of past-year drinking frequency, usual amount of alcohol consumed on drinking days, binge drinking frequency, intoxication frequency, and maximum number of drinks in a 24-hour period.
FINDINGS
Four different patterns emerged. First, several alcohol use disorder criteria were relatively weakly associated with externalizing and internalizing. Second, withdrawal was associated with internalizing, but this association was not specific to distress. Third, there was a general lack of specificity between alcohol use disorder criteria and narrower forms of internalizing, despite what might be predicted by modern models of addiction. Fourth, recurrent use in hazardous situations reflected higher degrees of externalizing and lower internalizing liability.
CONCLUSIONS
Different symptom combinations appear to yield differential expressions of alcohol use disorder that are disorder-specific, or reflect broader tendencies toward externalizing, internalizing, or both.
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No pos
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No neg
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Retriever1371
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Protein tyrosine phosphatases expressed in the developing rat brain.
Previous studies of the developing nervous system have shown that cell-cell and cell-matrix interactions are involved in a variety of processes such as the proliferation, migration, and differentiation of neurons. While many cell-surface molecules have been identified, the signal transduction mechanisms through which they modify cellular responses are poorly understood. Recent studies have described a new and large family of enzymes, protein tyrosine phosphatases (PTPases), that may play a key role in transduction of cell surface events. Opposing the actions of protein tyrosine kinases (PTKs), PTPases can determine the state of tyrosine phosphorylation of a protein and regulate its function. Within the family of PTPases, two subgroups have been characterized: low-molecular-weight cytoplasmic (nonreceptor) PTPases and high-molecular-weight transmembrane (receptor) PTPases. Many receptor PTPases have fibronectin type III and/or Ig-like domains in their extracellular domains, suggesting that they have dual functions: cell adhesion and signal transduction. Such molecules may play a role in cellular recognition events that mediate the accurate assembly of the nervous system. Using polymerase chain reaction with degenerate primers and a neonatal rat cortex cDNA library, we have identified a number of putative PTPase domains expressed in brain. Three are characterized here. These three sequences are most abundantly expressed in the developing cortex and so are named cortex-enriched protein tyrosine phosphatases (CPTPs) 1, 2, and 3. CPTP1 and CPTP3 show sequence homology to receptor PTPases and detect multiple high-molecular-weight mRNAs that are expressed preferentially in the developing CNS. Analysis of a longer cDNA indicates that CPTP1 and CPTP3 are the first and second phosphatase domains of a single receptor PTPase. CPTP2 identifies a single, smaller mRNA species with sequence homology to nonreceptor PTPases. Within the CNS, mRNAs detected by all three CPTPs are expressed at highest levels during prenatal and early postnatal days and are downregulated in the adult. In situ hybridization demonstrates that the CPTPs are expressed by progenitor cells and developing neurons. The spatial and temporal regulation of CPTPs suggests that they may play a role in neuronal development.
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No pos
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No neg
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Retriever1372
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Brain chemistry and behaviour.
The functional organization of chemically transmitting synapses in the brain are described with special emphasis on recent studies demonstrating the localization of different transmitters to specific anatomical circuitries. The use of pharmacological tools for manipulating levels of chemical transmitters is referred to briefly, but particular attention is given to the problems of studying the function of these pathways with lesion techniques. Noradrenaline (NA) and dopamine (DA) are selected for detailed consideration and experimental evidence reviewed, suggesting that these two catecholamines in the forebrain serve different functions: NA with processes of attention essential for learning, and DA with the execution of appropriate responses. Hypotheses suggesting dysfunction of forebrain DA and NA systems in schizophrenia are discussed.
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No pos
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No neg
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Retriever1373
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Histological evaluation of bone response to pediatric endodontic pastes: an experimental study in guinea pig.
This study aimed to evaluate by the intra-osseous implant technique the most commonly used materials for pulp therapy in pediatric dentistry: calcium hydroxide (CH), Guedes Pinto paste and CTZ paste, according to FDI (1980) and ANSI/ADA (1982) recommendations. Thirty guinea pigs, 10 for each material, divided into experimental periods of 4 and 12 weeks received one implant on each side of the lower jaw symphysis. The external lateral tube wall served as control for the technique. At the end of the observation periods, the animals were euthanized and specimens were prepared for routine histological examination. It was observed that CH and CTZ paste induced severe inflammation, a large amount of necrotic tissue, lymphocytes, foreign body cells and bone resorption, while Guedes Pinto Paste induced little or no inflammation in the 4-week observation period. After 12 weeks, the reactions to CH and Guedes Pinto paste were also absent/mild, presenting a general pattern of replacement by recently formed bone tissue while a moderate to severe inflammatory response was observed with CTZ paste. Guedes Pinto paste presented acceptable biocompatibility levels in both analyzed periods; CH only showed acceptable biocompatibility in the 12-week period while CTZ paste showed no biocompatibility in both periods. Among the tested materials, only Guedes Pinto paste presented an acceptable biocompatibility.
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No pos
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No neg
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Retriever1374
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Chest wall resection and reconstruction: a true thoracoscopic approach.
We set out to perform resection of a chest wall mass with subsequent reconstruction using a pure thoracoscopic approach. Using video-assisted thoracic surgery via a three-incision approach, we successfully removed an 8.5 × 3.5-cm specimen en bloc. We then reconstructed the chest wall with 2-mm polytetrafluoroethylene. A total thoracoscopic approach to chest wall resection and reconstruction represent an additional option in this area of thoracic surgery. This approach avoids some of the drawbacks of more invasive procedures. This report outlines a totally thoracoscopic approach that we feel represents a safe and viable option for patients requiring chest wall resection and reconstruction.
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No pos
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No neg
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Retriever1375
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Lipids: a personal view of the past decade.
The past decade has witnessed considerable progress in the field of lipids. New drugs have been "rapidly" developed and some of these drugs have already been evaluated in event-based large trials. This evidence has led to the guidelines recommending new, more aggressive treatment goals for low-density lipoprotein cholesterol (LDL-C) levels. Although LDL-C remains the principal goal for cardiovascular disease (CVD) risk reduction, there has also been considerable interest in other lipid variables, such as high-density lipoprotein cholesterol, triglycerides, and lipoprotein(a). Statin intolerance is now considered a very important topic in daily clinical practice. This has resulted in more attention focusing on non-statin drugs [e.g., ezetimibe and proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitors] and statin-related side effects. The latter mainly involve muscles, but there is also a need to consider other adverse effects associated with statin use (e.g., new onset diabetes). New specific areas of statin use have attracted interest. For example, statin-loading before procedures (e.g., coronary stenting), the prevention of stroke, and the treatment of non-alcoholic fatty liver disease (NAFLD). Statins will remain the most widely used drugs to treat dyslipidaemia and decrease CVD risk. However, we also need to briefly consider some other lipid-lowering drugs, including those that may become available in the future.
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No pos
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No neg
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Retriever1376
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RBE of 25 kV X-rays for the survival and induction of micronuclei in the human mammary epithelial cell line MCF-12A.
The broad application of low energy X-rays below about 50 keV in radiation therapy and diagnostics and especially in mammography substantiates the precise determination of their relative biological effectiveness (RBE). A quality factor of 1 is stated for photons of all energies in the International Commission on Radiological Protection Recommendations. However, the RBE of low-energy X-rays compared to high-energy photons was found to be dependent on photon energy, cell line and endpoints studied, hence varying from less than one up to about four. In the present study, the human mammary epithelial cell line MCF-12A has been chosen due to the implementation of the results in the estimation of risk from mammography procedures. The RBE of 25 kV X-rays (W anode, 0.3 mm Al filter) relative to 200 kV X-rays (W anode, 0.5 mm Cu filter) was determined for clonogenic survival in the dose range 1-10 Gy and micronuclei (MN) induction in the range 0.5-3.5 Gy. The RBE for clonogenic survival was found to be significantly higher than 1 for surviving fractions in the range 0.005<S<0.2. The RBE decreased with increasing survival, with an RBE0.1 at 10% survival of 1.13+/-0.03. The effectiveness of soft X-rays for MN induction was found to be 1.40+/-0.07 for the fraction of binuclear cells (BNC) with MN and 1.44+/-0.17 for the number of MN per BNC. In contrast, the RBE determined from the number of MN per MN-bearing BNC was found to be 1.08+/-0.32. This indicates that the effectiveness of 25 kV X-rays results from an increase in the number of damaged cells, which, however, do not have higher number of MN per cell.
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No pos
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No neg
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Retriever1377
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Chromatic response of polydiacetylene vesicle induced by the permeation of methotrexate.
The noble vesicular system of polydiacetylene showed a red shift using two types of detecting systems. One of the systems involves the absorption of target materials from the outer side of the vesicle, and the other system involves the permeation through the vesicular layers from within the vesicle. The chromatic mixed vesicles of N-(2-aminoethyl)pentacosa-10,12-diynamide (AEPCDA) and dimethyldioctadecylammonium chloride (DODAC) were fabricated by sonication, followed by polymerization by UV irradiation. The stability of monomeric vesicles was observed to increase with the polymerization of the vesicles. Methotrexate was used as a target material. The polymerized mixed vesicles having a blue color were exposed to a concentration gradient of methotrexate, and a red shift was observed indicating the adsorption of methotrexate on the polydiacetylene bilayer. In order to check the chromatic change by the permeation of methotrexate, we separated the vesicle portion, which contained methotrexate inside the vesicle, and checked chromatic change during the permeation of methotrexate through the vesicle. The red shift apparently indicates the disturbance in the bilayer induced by the permeation of methotrexate. The maximum contrast of color appeared at the equal molar ratio of AEPCDA and DODAC, indicating that the formation of flexible and deformable vesicular layers is important for red shift. Therefore, it is hypothesized that the system can be applicable for the chromatic detection of the permeation of methotrexate through the polydiacetylene layer.
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No pos
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No neg
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Retriever1378
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Fermented wheat germ extract induced cell death and enhanced cytotoxicity of Cisplatin and 5-Fluorouracil on human hepatocellular carcinoma cells.
Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related death worldwide. Due to the difficulties of early diagnosis, curative treatments are not available for most patients. Palliative treatments such as chemotherapy are often associated with low response rate, strong adverse effects and limited clinical benefits for patients. The alternative approaches such as fermented wheat germ extract (FWGE) with anti-tumor efficacy may provide improvements in the clinical outcome of current therapy for HCC. This study aimed to clarify antitumor efficacy of FWGE and the combination drug effect of FWGE with chemotherapeutic agents, cisplatin and 5-fluorouracil (5-Fu) in human HCC cells, HepG2, Hep3B, and HepJ5. The present study indicated that FWGE exhibited potential to suppress HepG2, Hep3B, and HepJ5 cells, with the half maximal inhibitory concentrations (IC50) of FWGE were 0.494, 0.371 and 1.524 mg/mL, respectively. FWGE also induced Poly (Adenosine diphosphate ribose) polymerase (PARP) associated cell death in Hep3B cells. Moreover, the FWGE treatment further enhanced the cytotoxicity of cisplatin in all tested HCC cells, and cytotoxicity of 5-Fu in a synergistic manner in HepJ5 cells. Collectively, the results identified the anti-tumor efficacy of FWGE in HCC cells and suggested that FWGE can be used as a supplement to effectively improve the tumor suppression efficiency of cisplatin and 5-Fu in HCC cells.
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No pos
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No neg
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Retriever1379
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Effects of dietary thyme and rosemary essential oils on performance parameters with lipid oxidation, water activity, pH, colour and microbial quality of breast and drumstick meats in broiler chickens.
This study was aimed at determining the effects of different doses of thyme essential oil (TEO) and rosemary essential oil (REO) incorporated into broiler rations on performance parameters, including body weight gain, feed intake and feed conversion rate, as well as on the quality criteria of breast and drumstick meat. The study material comprised of 400 three-day-old male Ross 308 chicks, which were assigned to five groups, each of 80 broilers. Each group was divided into four sub-groups of 20 animals. In this study, the feed rations provided to the control group and groups TEO-150, TEO-300, REO-100 and REO-200 were supplemented with 0, 150 mg kg TEO, 300 mg kg TEO, 100 mg kg REO and 200 mg kg REO, respectively. Fattening performance parameters were statistically similar in the control group and all trial groups ( ). It was determined that, while dietary supplementation with TEO and REO significantly reduced total mesophilic aerobic bacteria (TMAB) counts throughout storage in drumstick meat and on days 0 and 8 of storage in breast meat ( ), it showed variable effects on other microbial counts and during other time points in both breast meat and drumstick meat. Dietary supplementation with TEO and REO was ascertained not to affect the pH value of breast and drumstick meat and to show limited and variable effects on colour parameters and water activity throughout the storage period of breast and drumstick meat. In all groups supplemented with TEO and REO, the thiobarbituric acid reactive substance (TBARS) levels of drumstick meat were observed to have significantly decreased on days 0, 2 and 4 of storage ( ). As a result, dietary supplementation with TEO and REO was determined to have a limited effect on performance parameters, but to improve the microbial quality of meat.
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No pos
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No neg
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Retriever1380
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Mapping cellular senescence networks in human diabetic foot ulcers.
Cellular senescence, a cell fate defined by irreversible cell cycle arrest, has been observed to contribute to chronic age-related conditions including non-healing wounds, such as diabetic foot ulcers. However, the role of cellular senescence in the pathogenesis of diabetic foot ulcers remains unclear. To examine the contribution of senescent phenotypes to these chronic wounds, differential gene and network analyses were performed on publicly available bulk RNA sequencing of whole skin biopsies of wound edge diabetic foot ulcers and uninvolved diabetic foot skin. Wald tests with Benjamini-Hochberg correction were used to evaluate differential gene expression. Results showed that cellular senescence markers, CDKN1A, CXCL8, IGFBP2, IL1A, MMP10, SERPINE1, and TGFA, were upregulated, while TP53 was downregulated in diabetic foot ulcers compared to uninvolved diabetic foot skin. NetDecoder was then used to identify and compare context-specific protein-protein interaction networks using known cellular senescence markers as pathway sources. The diabetic foot ulcer protein-protein interaction network demonstrated significant perturbations with decreased inhibitory interactions and increased senescence markers compared to uninvolved diabetic foot skin. Indeed, TP53 (p53) and CDKN1A (p21) appeared to be key regulators in diabetic foot ulcer formation. These findings suggest that cellular senescence is an important mediator of diabetic foot ulcer pathogenesis.
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No pos
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No neg
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Retriever1381
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Substrate specificities of murine C1s.
An early step in the initiation of the classical C pathway is the proteolytic activation of component C4 by subcomponent C1-s. We have examined the substrate specificity of murine C1-s (mC1-s) by measuring its proteolytic activity on human and murine C4, and on the murine C4 isotype designated sex-limited protein (Slp). The latter substrate was examined because previous studies have demonstrated that Slp is not cleaved by C1-s, and hence Slp has been assumed to be nonfunctional in the C pathways. Those earlier studies used human, not murine, C1-s, however; a recent report has suggested that Slp is an essential component of a novel complement activation pathway and that the previous failure to observe cleavage of Slp is probably the result of a species incompatibility between Slp and the heterologous human C1-s (hC1-s). The present studies do not support this idea, as we found no evidence of cleavage of Slp by homologous murine C1-s even at enzyme concentrations 10-fold higher than that necessary for 50% cleavage of murine C4 (mC4). We did find a species-specific affect in the cleavage of mC4, where mC1-s is about 10-fold more effective than heterologous hC1-s in cleaving mC4, but mC1-s itself does not distinguish between human and murine C4, cleaving both equally well. Hence mC1-s does not exhibit the species specificity previously found for hC1-s, which shows a several hundred-fold preference for homologous human C4 over murine C4.
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No pos
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No neg
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Retriever1382
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Disentangling the genetic bases of Saccharomyces cerevisiae nitrogen consumption and adaptation to low nitrogen environments in wine fermentation.
The budding yeast Saccharomyces cerevisiae has been considered for more than 20 years as a premier model organism for biological sciences, also being the main microorganism used in wide industrial applications, like alcoholic fermentation in the winemaking process. Grape juice is a challenging environment for S. cerevisiae, with nitrogen deficiencies impairing fermentation rate and yeast biomass production, causing stuck or sluggish fermentations, thus generating sizeable economic losses for wine industry. In the present review, we summarize some recent efforts in the search of causative genes that account for yeast adaptation to low nitrogen environments, specially focused in wine fermentation conditions. We start presenting a brief perspective of yeast nitrogen utilization under wine fermentative conditions, highlighting yeast preference for some nitrogen sources above others. Then, we give an outlook of S. cerevisiae genetic diversity studies, paying special attention to efforts in genome sequencing for population structure determination and presenting QTL mapping as a powerful tool for phenotype-genotype correlations. Finally, we do a recapitulation of S. cerevisiae natural diversity related to low nitrogen adaptation, specially showing how different studies have left in evidence the central role of the TORC1 signalling pathway in nitrogen utilization and positioned wild S. cerevisiae strains as a reservoir of beneficial alleles with potential industrial applications (e.g. improvement of industrial yeasts for wine production). More studies focused in disentangling the genetic bases of S. cerevisiae adaptation in wine fermentation will be key to determine the domestication effects over low nitrogen adaptation, as well as to definitely proof that wild S. cerevisiae strains have potential genetic determinants for better adaptation to low nitrogen conditions.
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No pos
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No neg
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Retriever1383
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Co-administration of L-Ascorbic Acid and α-Tocopherol Alleviates Arsenic-Induced Immunotoxicities in the Thymus and Spleen by Dwindling Oxidative Stress-Induced Inflammation.
Herein, we investigated whether L-ascorbic acid (L-AA) and α-tocopherol (α-T) co-administration has the potential to alleviate arsenic-induced immunotoxicities in the thymus, spleen, and circulating leukocytes. Forty-eight adult male Wistar rats were randomly divided into four groups before the treatment: group I (control); group II (sodium arsenite, 3 mg/kg/day/rat); group III (sodium arsenite + L-AA (200 mg/kg/day/rat) and α-T (400 mg/kg/day/rat)); group IV (L-AA and α-T). The result showed that sodium arsenite exposure (consecutive 30 days) caused weight reduction, structural alterations in the thymus and spleen, accompanied by a decrease in thymocyte and splenocyte count. Decreased superoxide dismutase and catalase activity, increased malondialdehyde and protein-carbonyl content, reduced Nrf2 and Bcl2 expression, and increased p-ERK, NF-kβ, Bax, and cleaved-caspase-3 expression were also observed in the thymus and spleen of arsenic-exposed rats. Enhanced plasma ACTH and corticosterone, ROS-induced apoptosis of lymphocytes were also observed. L-AA and α-T co-administration has the potential to abrogate the deleterious impact of arsenic on the thymus, spleen, and circulating lymphocytes. Whole transcriptome analysis of leukocytes revealed that arsenic treatment augmented the expression of Itga4, Itgam, and MMP9 genes, which might help in transient migration of the leukocytes through the endothelial cell layer. Co-administration with L-AA and α-T maintained Itga4, Itgam, and MMP9 gene expression within leukocytes at a lower level.
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No pos
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No neg
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Retriever1384
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Colforsin daropate improves contractility in fatigued canine diaphragm.
UNLABELLED
We studied the effects of colforsin daropate, a water-soluble forskoline derivative, on contractility in fatigued canine diaphragm. Dogs were randomly divided into 4 groups of 8 each. In each group, diaphragmatic fatigue was induced by intermittent supramaximal bilateral electrophrenic stimulation at a frequency of 20 Hz applied for 30 min. Immediately after the end of a fatigue-producing period, Group 1 received no study drug, Group 2 was infused with small-dose colforsin daropate (0.2 microg. kg(-1). min(-1)), Group 3 was infused with large-dose colforsin daropate (0.5 microg. kg(-1). min(-1)), and Group 4 was infused with nicardipne (5 microg. kg(-1). min(-1)) during colforsin daropate (0.5 microg. kg(-1). min(-1)) administration. After the fatigue-producing period, in each group transdiaphragmatic pressure (Pdi) at low-frequency (20-Hz) stimulation decreased from baseline values (P < 0.05), whereas there was no change in Pdi at high-frequency (100-Hz) stimulation. In Groups 2 and 3, during colforsin daropate administration, Pdi to each stimulus increased from fatigued values (P < 0.05). The increase in Pdi was larger in Group 3 than in Group 2 (P < 0.05). In Group 4, the augmentation of Pdi by colforsin daropate was abolished in fatigued diaphragm with an infusion of nicardipine. The integrated diaphragmatic electric activity did not change in any of the groups. We conclude that colforsin daropate improves, in a dose-dependent manner, contractility in fatigued canine diaphragm via its effect on transmembrane calcium movement.
IMPLICATIONS
Diaphragmatic fatigue is implicated as a cause of respiratory failure in normal subjects and in patients with chronic obstructive lung disease. Colforsin daropate improves contractile properties during diaphragmatic fatigue.
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No pos
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No neg
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Retriever1385
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The Ex Vivo Organ Culture of Bone.
The ex vivo organ culture of bone provides many of the advantages of both the whole organism and isolated cell strategies and can deliver valuable insight into the network of processes and activities that are fundamental to bone and cartilage biology. Through maintaining the bone and/or cartilage cells in their native environment, this model system provides the investigator with a powerful experimental protocol to address specific facets of skeletal growth and development. In this chapter, we outline the basic protocols and possible readouts of organ culture models to replicate; (a) linear bone growth (murine metatarsal culture model), (b) bone and cartilage metabolism (murine femoral head culture model), (c) bone response to mechanical stimulation (bovine trabecular core culture model), and (d) bone resorption and formation (murine calvaria culture model).
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No pos
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No neg
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Retriever1386
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Increased Evi-1 expression is frequently observed in blastic crisis of chronic myelocytic leukemia.
Evi-1 is a transforming gene originally identified in a common integration site of murine leukemia retrovirus and mapped in human chromosome 3q26. It is not normally expressed in either human or murine hematopoietic cells, but is overexpressed in retrovirus-induced murine myeloid leukemias as well as human myeloid leukemias with 3q26 abnormalities, and thus thought to be responsible for both human and murine leukemogenesis. In this study, possible involvement of the Evi-1 gene in human leukemias was evaluated by Northern blot analysis in a total of 73 patients with various types of leukemias. We found that increased expression of the Evi-1 gene was most frequently observed in patients with CML in blastic crisis. It was found in 10 of 14 (71.0%) samples from CML in blastic crisis, three of 15 (20.0%) from acute myelocytic leukemia, three of 11 (27.3%) from MDS-derived leukemia, and one of 11 (9.1%) from acute lymphoblastic leukemia. Among 18 patients showing increased Evi-1 expression, none of 17 informative patients showed cytogenetic abnormalities involving 3q26. In addition, Southern blot analysis revealed neither amplification nor rearrangements of the Evi-1 gene in 11 Evi-1-positive patients whose DNA samples were available. Our results suggest that increased expression of the Evi-1 gene may play an important role in development of human leukemias, especially in progression from chronic phase to blastic crisis of CML even without 3q26 abnormalities.
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No pos
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No neg
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Retriever1387
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Circulating immune complexes in patients with lung neoplasms.
A search was made for circulating immune complexes in 42 patients with biopsy-proven lung cancer; sex- and age-matched healthy volunteers were used as normal controls. Two different mthods were employed: Clq--binding assay and the conglutinin-binding test. Patients and controls were also examined for delayed hypersensitivity by a skin testing using a set of recall antigens. A significant difference was found in the incidence of immune complexes and the response to skin tests between neoplastic subjects and normal controls. However, the incidence of immune complexes was not related to delayed hypersensitivity or the other clinical features investigated.
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No pos
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No neg
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Retriever1388
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Increased incidence and improved survival in endometrioid endometrial cancer diagnosed since 1989 in The Netherlands: a population based study.
OBJECTIVES
To measure progress against endometrioid endometrial carcinoma (EEC) in the Netherlands by analyzing trends in incidence, survival and mortality simultaneously.
STUDY DESIGN
Descriptive study of incidence, survival and mortality rates of women with EEC in the Netherlands. Rates were age-standardized to the European standard population. Population-based data were extracted from the nationwide Dutch Cancer Registry (NCR) between 1989 and 2009. Mortality data since 1989 came from Statistics Netherlands. European age standardized incidence rates were calculated according to age, histology and stage. Five year relative survival estimates were calculated in four periods. Optimal progress against cancer is defined as decreasing incidence and/or improving survival accompanied by declining mortality.
RESULTS
80% of the 32,332 patients newly diagnosed with a corpus uteri malignancy had an EEC. The incidence of EEC rose significantly from 11/100,000 to 15/100,000, being most pronounced in women with FIGO stage IB and in the group with grade 1&2 tumours (P<0.05). Coinciding with the increased incidence, 5-year relative survival increased, especially for patients aged 60-74 years, in women with FIGO stage I, and in histology group grade 1&2, being 87%, 94% and 93%, respectively, during 2005-2009.
CONCLUSION
The incidence of EEC (being 80% of corpus uteri cancer) increased markedly between 1989 and 2009, especially in women of 60-74 years. Five-year survival for patients with EEC increased from 83 to 85%. Progress against EEC has been less than was assumed previously, because mortality proportionally decreased only slightly, and because of the increasing incidence although survival improved.
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No pos
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No neg
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Retriever1389
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Transcriptome Sequencing to Identify Candidate Genes for Mycelium Period Metabolism of Chinese Caterpillar Mushroom, Ophiocordyceps sinensis (Ascomycetes), Exposed to Light Treatment.
The Chinese caterpillar mushroom, Ophiocordyceps sinensis, is rare in traditional Chinese herbal medicine. It was reported that the development of ascospores in sexual stage of Chinese Cordyceps requires certain UV irradiation, but whether light has effect on the asexual stage of O. sinensis is unclear. It is important and necessary to identify the candidate genes involved in asexual stages (mycelium period) metabolism of O. sinensis exposed to light treatment. In this study, the isolated and purified monoascospore strains from O. sinensis were treated with 10 days light (L10) and dark as control. Transcriptome sequencing (RNA-seq) was conducted to investigate the effect of light treatment on O. sinensis at the gene level and the changes in various metabolic pathways. The results showed that the colony surface was covered with villous aerial hyphae with a yellow circular mycelium ribbon in the center of the colony, and the content of polysaccharides, urea, adenosine, and cordycepin were significantly enhanced by L10 treatment. Kyoto Encyclopedia of Genes and Genomes (KEGG) functional annotation analysis showed that cell structure and catalytic metabolism were the significant items classified, and crucial genes affecting the anabolic pathways of polysaccharides, urea, adenosine, and cordycepin were also identified. In addition, the important roles of photoreceptor genes CRYD, WC-1, and FRQ were verified by combined analysis of qRT-PCR and transcriptome sequencing. Collectively, this study would be helpful to better understand the influence of light on the asexual stage of Chinese Cordyceps and provide a preliminary light treatment reference for Cordyceps artificial cultivation.
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No pos
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No neg
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Retriever1390
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Clinical application of protein-enhanced diet using mealworms in patients undergoing hepato-pancreato-biliary surgery.
OBJECTIVE
Patients with or without cancers who undergo major gastrointestinal surgery experience malnutrition owing to their catabolic status during the postoperative period. In this study, we evaluated the effect of the clinical application of protein-enhanced diet using mealworms in patients who underwent hepato-pancreato-biliary surgeries.
METHODS
This study was designed as a prospective, two-armed, and double-blinded phase III study. The target number of enrolled patients was 216, and the patients were randomized on a 1:1 basis, either to the trial group (consuming mealworms) or to the control group (consuming grain powder). The primary endpoint was to examine the changes in body composition, including phase angle. For secondary outcomes, the activities of immune cells were evaluated using the patients' blood samples.
RESULTS
No difference in the demographic characteristics of patients was observed. The ratio of the actual protein intake to the recommended daily intake in the trial group was significantly higher than that in the control group (110.03% vs. 98.80%, P = 0.023). In the data on body composition measured by InBody S-10 (Biospace, Seoul, South Korea), the ratios in body cell mass, fat free mass, muscle mass, and phase angle at the study endpoint compared with those at admission showed no statistically significant difference between the two groups. Immune cell analyses suggested that cytotoxic T cells in the trial group had higher activity than in the study group (1.192 vs. 0.974, P = 0.028).
CONCLUSIONS
In this study, protein-enhanced diet using mealworms clinically improved the activity of immune cells. However, it did not significantly improve the patients' nutritional status after they experienced hepato-pancreato-biliary surgeries.
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No pos
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No neg
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Retriever1391
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Energy Level Alignment at Metal/Solution-Processed Organic Semiconductor Interfaces.
Energy barriers between the metal Fermi energy and the molecular levels of organic semiconductor devoted to charge transport play a fundamental role in the performance of organic electronic devices. Typically, techniques such as electron photoemission spectroscopy, Kelvin probe measurements, and in-device hot-electron spectroscopy have been applied to study these interfacial energy barriers. However, so far there has not been any direct method available for the determination of energy barriers at metal interfaces with n-type polymeric semiconductors. This study measures and compares metal/solution-processed electron-transporting polymer interface energy barriers by in-device hot-electron spectroscopy and ultraviolet photoemission spectroscopy. It not only demonstrates in-device hot-electron spectroscopy as a direct and reliable technique for these studies but also brings it closer to technological applications by working ex situ under ambient conditions. Moreover, this study determines that the contamination layer coming from air exposure does not play any significant role on the energy barrier alignment for charge transport. The theoretical model developed for this work confirms all the experimental observations.
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No pos
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No neg
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Retriever1392
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[The significance of "A neuroanatomical basis for electroacupuncture to drive the vagal-adrenal axis" published in Nature for acupuncture research].
October 2021, Nature published an original research article entitled A neuroanatomical basis for electroacupuncture to drive the vagal-adrenal axis, which draws great attention and arouses extensive discussion in the acupuncture field. Based on previous findings, this study demonstrates that the abundant innervation of PROKR2-Cre neurons in deep fascia tissues mediates the anti-inflammatory effect induced by low-intensity electroacupuncture stimulation at "Zusanli"（ST36） or "Shousanli"(LI10) via the "vagal-adrenal axis". This study is one of milestones in the field of acupuncture basic research and represents a great achievement generated by multi-discipline integration of acupuncture and neuro-immunology. It reveals partial contributing factors involved in acupuncture's effect and the relative specificity of the neuroanatomical basis of acupoints in the context of immune modulation. This study is both very informative and instructive for the innovation and clinical translation of future acupuncture research. Acupuncture researchers are recommended to attach great importance to this study in terms of its research strategy,methods and findings.
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No pos
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No neg
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Retriever1393
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Interventions for preventing or controlling healthcare-associated infection amongst healthcare workers or patients within primary care facilities: a scoping review.
BACKGROUND
This review aimed to synthesize the evidence on infection prevention and control (IPC) interventions for the prevention of healthcare-associated infection (HAI) amongst healthcare workers (HCW) or patients within primary care facilities.
METHODS
PubMed, CINAHL, EMBASE and CENTRAL databases were searched for quantitative studies published between 2011-2022. Study selection, data extraction and quality assessment using Cochrane and Joanna Briggs tools, were conducted by independent review with additional sensitivity checking performed on study selection.
RESULTS
Four studies were included. A randomized trial and a cross-sectional survey, respectively, found no statistical difference in laboratory-confirmed influenza in HCW wearing N95 versus medical masks (p=0.18) and a significant inverse association between the implementation of tuberculosis (TB) control measures and TB incidence (p=0.02). For the prevention of surgical site infections following minor surgery, randomized trials found non-sterile gloves (8.7%; 95% CI, 4.9%-12.6%) to be non-inferior to sterile gloves (9.3%; 95% CI, 7.4%-11.1%) and no significant difference between prophylactic antibiotics compared to placebo (p=0.064). All studies had a high risk of bias.
CONCLUSION
Evidence for IPC interventions for prevention of HAI in primary care is very limited and insufficient to make practice recommendations. Nevertheless, the findings highlight the need for future research.
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No pos
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No neg
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Retriever1394
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Examining the subjective fairness of at-home and online tests: Taking Duolingo English Test as an example.
The Duolingo English Test, a language proficiency test offered online, is now getting prevalent worldwide. A recap of existing literature denotes that there is an insufficient examination of the DET, particularly on its issues of fairness. Besides, empirical test fairness research had mainly focused on the objective aspect but may have overlooked the importance of its subjective aspect. Additionally, compared with in-person tests, the fairness research of at-home tests lags far behind. Therefore, the current study investigated the DET fairness from test takers' perspectives. A DET Fairness Questionnaire based on (Kunnan's AJ, 2004) Test Fairness Framework (comprising validity, absence of bias, access, administration, and social consequences) was developed. Data were collected from 1,012 Chinese university students and processed through descriptive and factor analyses. The descriptive analyses revealed that test takers perceived the DET to be fair overall. Specifically, they perceived that they had equal access to the test, but the test was invalid; the factor analyses showed that test takers' perceptions of DET fairness (especially perceived validity and access) had a significant effect on their test performance. Such findings suggest that the subjective test fairness as an essential component could not be neglected in appraising an assessment as it influences test takers' performance, and DET developers may strive harder to enhance the validity of DET to provide a fairer testing environment for test takers.
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No pos
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No neg
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Retriever1395
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An insulator element located at the cyclin B1 interacting protein 1 gene locus is highly conserved among mammalian species.
Insulators are cis-elements that control the direction of enhancer and silencer activities (enhancer-blocking) and protect genes from silencing by heterochromatinization (barrier activity). Understanding insulators is critical to elucidate gene regulatory mechanisms at chromosomal domain levels. Here, we focused on a genomic region upstream of the mouse Ccnb1ip1 (cyclin B1 interacting protein 1) gene that was methylated in E9.5 embryos of the C57BL/6 strain, but unmethylated in those of the 129X1/SvJ and JF1/Ms strains. We hypothesized the existence of an insulator-type element that prevents the spread of DNA methylation within the 1.8 kbp segment, and actually identified a 242-bp and a 185-bp fragments that were located adjacent to each other and showed insulator and enhancer activities, respectively, in reporter assays. We designated these genomic regions as the Ccnb1ip1 insulator and the Ccnb1ip1 enhancer. The Ccnb1ip1 insulator showed enhancer-blocking activity in the luciferase assays and barrier activity in the colony formation assays. Further examination of the Ccnb1ip1 locus in other mammalian species revealed that the insulator and enhancer are highly conserved among a wide variety of species, and are located immediately upstream of the transcriptional start site of Ccnb1ip1. These newly identified cis-elements may be involved in transcriptional regulation of Ccnb1ip1, which is important in meiotic crossing-over and G2/M transition of the mitotic cell cycle.
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No pos
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No neg
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Retriever1396
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High power, ultrashort pulse control through a multi-core fiber for ablation.
Ultrashort pulse ablation has become a useful tool for micromachining and biomedical surgical applications. Implementation of ultrashort pulse ablation in confined spaces has been limited by endoscopic delivery and focusing of a high peak power pulse. Here we demonstrate ultrashort pulse ablation through a thin multi-core fiber (MCF) using wavefront shaping, which allows for focusing and scanning the pulse without requiring distal end optics and enables a smaller ablation tool. The intensity necessary for ablation is significantly higher than for multiphoton imaging. We show that the ultimate limitations of the MCF based ablation are the nonlinear effects induced by the pulse in the MCFs cores. We characterize and compare the performance of two devices utilizing a different number of cores and demonstrate ultrashort pulse ablation on a thin film of gold.
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No pos
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No neg
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Retriever1397
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Electronic effect of terminal acceptor groups on different organic donor-acceptor small-molecule based memory devices.
In this work, three new organic donor–acceptor small-molecules, in which bicarbazole served as the electron donor, and benzothiazole, nitryl or 1,1′-dicyanovinyl were used as the electron acceptor, were designed and synthesized in order to fabricate sandwiched memory devices. Acceptors with a variable electron-delocalized extent and electron-withdrawing strength were attached to the molecular backbone in order to investigate the effect on the devices switching behavior. The bi-n-butylcarbazole benzothiazole (BCZ-BT) based memory device exhibited volatile static random access memory (SRAM) switching behaviour, while the devices based on bi-n-butylcarbazole nitryl (BCZ-NO2) was found to exhibit stable nonvolatile write-once-read-many-times (WORM) data storage characteristics and the bi-n-butylcarbazole dicyanovinyl (BCZ-CN) device acted as rewritable flash memory with a higher ON/OFF current ratio of about 104. Therefore, tunable data storage devices synthesized by adjusting the terminal acceptor groups offer feasible guidance for the rational design of organic molecules to achieve superior memory performance.
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No pos
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No neg
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Retriever1398
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Predictors Associated with COVID-19 Deaths in Ethiopia.
Coronavirus disease is an infectious disease that causes a newly discovered coronavirus. Ethiopia is one of the most impacted countries relative to the proportion of COVID-19 case growth and infection. The purpose of this investigation was to identify the determinants of COVID-19 deaths in Ethiopia. The source of the data for this study was the 2020 Ethiopian Ministry of Health from March up to July using multiple linear regression models. Among 468,814 total tests, 9,027 were recovered, 20,900 were confirmed cases, and 365 were deaths from coronavirus diseases in Ethiopia. Critical cases (β= 0.570, p= 0.006) and average temperature (β= -35.061, p= 0.003) variables were statistically significant. Critical or serious cases significantly and positively affected the deaths from this pandemic disease, while the average temperature significantly and negatively affected the deaths from COVID-19 disease in Ethiopia.
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No pos
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No neg
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Retriever1399
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[A new description of the type strain of Halobacterium distributum].
The descriptions of strains assigned to the species Halobacterium distributum were supplemented with the results of chemo-and genotaxonomic studies. According to these data, H. distributum VKM B-1733, which was hitherto regarded as the type strain of H. distributum, cannot be assigned to this species. Instead, strain H. distributum VKM B-1739 is proposed as the type strain. It is also suggested that strain VKM B-1954 should be transferred to H. distributum.
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No pos
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No neg
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