Intestinal spirochaetes colonizing aborigines from communities in the remote north of Western Australia. Intestinal spirochaetal bacteria were isolated from 59 of 181 (32.6%) faecal samples obtained from Aboriginal children and a few adults living in communities in the Kimberley region in the north of Western Australia. Colonization was more common in young Aborigines between 2 and 18 years of age than it was in adults, or in babies and children less than 2 years of age. Three of 22 Aboriginal children who were sampled on two consecutive years were colonized on both occasions. None of four other children were found to be consistently colonized with the bacteria when sampled on three sequential years, but three were positive on two consecutive visits and the other child was positive on the first and third sampling. Most Aboriginal children had abnormal or watery stools, and both abnormal and watery stool samples were significantly more likely to contain spirochaetes than were normal samples. However, it was not possible to prove that the spirochaetes were the cause of the diarrhoea. In contrast, spirochaetes were only recovered from 8 of 695 (1.2%) faecal samples that were obtained from other mainly non-Aboriginal children and adults in Western Australia or the Northern Territory of Australia, even though most of these individuals were suffering from gastrointestinal disturbances.


Vector potential of hospital houseflies with special reference to Klebsiella species. The vector potential of houseflies (Musca domestica) for Klebsiella spp. was investigated. Klebsiella spp. (mostly Klebsiella pneumoniae) were isolated from 36.7% of hospital flies and 28.1% of infected wounds of patients. Antibiograms of Klebsiella spp. showed that 82.0% of isolates from hospital flies and 96.3% from infected wounds were resistant to four or more commonly used antimicrobials. In contrast, from the control group, only 8.7% klebsiella isolates showed similar antimicrobial resistance pattern (P less than 0.001). Similar strains of Klebsiella spp. were encountered among patients and hospital houseflies. The results indicate that flies in the hospital environs are potential vectors of hospital resistant strains of Klebsiella spp.


Short-term predictions of HIV prevalence and AIDS incidence. Reports of AIDS cases in Amsterdam up to February 1990 were used to make predictions of future cases up to 1993. Two published methods were applied, which make extrapolations from current cases and simultaneously estimate the extent of delay in reporting. The choice of the exact model greatly influenced the predictions, as did predictions for distinct transmission groups. We present results for the homo/bisexual male group, and the total population of Amsterdam. The AIDS case predictions are used to predict the HIV prevalence using the ratio of HIV prevalence to AIDS incidence and through 'back calculation'. We suggest that the ratio is a simple technique that may be used to estimate HIV prevalence. The estimated number of cumulative HIV infected homo/bisexual males in Amsterdam in January 1990 was between 2100 and 4100 in a total of 2200-4600 infected people.


An outbreak of hepatitis A in Gloucester, UK. During an outbreak of hepatitis A that occurred in Gloucester, UK between September 1989 and January 1991, 162 clinical cases were identified through notifications and laboratory reports, a monthly attack rate of 1.05 per 10,000 residents. The highest attack rate was seen in 5-14-year-olds. There were significant correlations between hepatitis A attack rates in the electoral wards of Gloucester and with the Jarman UPA 8 scores for the wards and with overcrowding, unemployment, under 5-year-olds and ethnic minority. The use of human normal immune globulin prophylaxis (HNIG) for household contacts was unsuccessful in ending the outbreak, partly because only one third of cases reported a household contact with recent hepatitis A. Our experience does not support the use of HNIG in stopping community-wide outbreaks of hepatitis A. Two public health campaigns were mounted during the outbreak; both were followed by a fall in the number of cases. Greater priority should be given to the implementation and evaluation of public health campaigns in future community-wide outbreaks of hepatitis A.


Mycobacterium bovis in England and Wales: past, present and future. This report reviews the literature concerning tuberculosis resulting from infection with Mycobacterium bovis in man and cattle and summarises data derived from surveillance of M. bovis in England and Wales from 1986 to 1990. Of the 228 isolates of M. bovis examined in this period, 122 (53%) were from patients aged over 60 years and are largely the result of reactivation of infection acquired prior to the institution of control measures. However, eight isolates (3.5%) were from patients aged less than 30 years. The potential sources for these presumed primary infections include the few remaining cattle infected with M. bovis or infectious human cases in the United Kingdom. However, infections acquired abroad, especially in immigrants, may account for some of these cases. Outbreaks of tuberculosis due to M. bovis continue to occur in cattle. Wild animals, particularly badgers, have been implicated as reservoirs of the infection. However, man may also prove to be an important reservoir of M. bovis for cattle as well as humans.


Legionella pneumophila in residential water supplies: environmental surveillance with clinical assessment for Legionnaires' disease. Although cases of community-acquired Legionnaires' disease have been epidemiologically linked to residential water supplies, the risk of acquiring Legionnaires' disease from exposure to Legionella pneumophila in residential water systems is uncertain. The residential water supplies of 218 members of the American Legion in six different geographical areas in Pittsburgh were cultured for L. pneumophila. Residents of the homes provided a recent medical history and a blood sample for detection of antibodies to legionella. A urine sample for legionella urinary antigen testing was also requested from individuals residing in legionella-positive homes and individuals with a positive antibody test. Six percent (14/218) of the homes yielded L. pneumophila (range within six areas 0-22%). Lower hot water tank temperature was significantly associated with legionella positivity (P less than 0.01). Analysis of water samples for mineral content showed no association between legionella positivity and concentrations of calcium and magnesium. Water samples from the area where 22% of the homes surveyed were positive for legionella had a higher iron content than water samples from the other areas tested. None of the individuals residing in legionella-positive homes showed elevated antibody titres to legionella or the presence of legionella antigen in urine. For the immunocompetent hosts, the risk of contracting Legionnaires' disease from exposure to contaminated household water supplies in the Pittsburgh area appears to be low.


Restriction endonuclease fingerprinting of genomic DNA of Staphylococcus species of bovine origin. Fifty-one staphylococcal isolates from mammary secretions of cows with subclinical mastitis were examined by antibiograms and DNA restriction endonuclease fingerprinting (REF). DNA REF differentiated closely related strains of each species isolated from mammary secretions of different mammary glands of the same cow and from the same mammary gland at different periods of the lactation cycle. In addition, REF analysis provided evidence concerning persistence of infection in the same or different mammary gland over different periods of the lactation cycle, and occurrence of infection with similar and dissimilar strains of each Staphylococcus species. Antibiograms were of limited value in differentiating closely related strains. The ease by which REF analysis can be performed together with the reproducibility and clarity of REF patterns suggest that this technique is useful for differentiating closely related and unrelated strains of Staphylococcus species isolated from bovine mammary secretions.


Helicobacter pylori, musings from the epidemiologic armchair. The literature on Helicobacter pylori has become enormous, but the epidemiology of the infection remains an enigma. Guided by epidemiologic principles we have tried to interpret the available data on the epidemiologic aspects of H. pylori. We conclude that conflicting results on familial clustering and seroprevalence curves might have logical explanations. However, the exact way this organism spreads among humans remains to be solved.


A study into the mechanism of the Crystal Violet reaction in Staphylococcus aureus. The mechanism of the Crystal Violet (CV) reaction, a trait which has been related to biotype, source and pathogenicity in Staphylococcus aureus, was investigated in agar and broth studies. White reactions could be converted to purple and vice versa by altering the incubation conditions on agar. Broth reactions examined macroscopically and by spectrophotometry revealed that both white and purple human biotype strains take up CV but the former then progressively modify the dye more quickly than the latter. A cell-associated product of CV was detected in white and purple strains by reverse-phase thin-layer chromatography of methanol extracts. White strains appear to produce a second additional product from CV. The white reaction was not inhibited by chloramphenicol or azide but did depend on viable cells with a nutrient source. CV MICs and MBCs for 10 white and 10 purple reactors showed no gross differences in susceptibility, while a standardized assay for the rate of CV modifying activity (52 strains) demonstrated that the two categories comprise discrete populations which alter CV at different rates. Although most white strains belong to either or both of phage-typing groups V and II, purple strains with this pattern of susceptibility and white strains without it both occur. The capacity to modify CV slowly or rapidly appears to subdivide human biotype strains independently of their phage group and is associated in the former case with their capacity to produce hospital-acquired and invasive infections.


The epidemiology of ciprofloxacin resistance in coagulase-negative staphylococci in CAPD patients. Ciprofloxacin was used as empirical therapy for peritonitis in patients receiving continuous ambulatory peritoneal dialysis (CAPD) for 26 months, providing an opportunity to study the epidemiology of ciprofloxacin resistance amongst coagulase-negative staphylococci (CNS). Swabs were collected from the CAPD patients, staff, and clinic environment before, during and after the time this antibiotic was prescribed. Clinical isolates were also studied, and records kept of patient hospital attendance. Ciprofloxacin-resistant staphylococci were typed by antibiogram, biotype, plasmid profile, SDS-PAGE, and immunoblotting. No resistant strains were detected before the use of ciprofloxacin. During its use 30% of patients became skin carriers, and resistant strains caused 8% of peritonitis episodes in 7% of patients (38% of carriers). Resistant strains were isolated from the environment, but never from attending members of staff. A total of 208 resistant isolates with MIC's between 8 and 128 mg/l was collected and identified as Staphylococcus epidermidis or S. haemolyticus. Sixteen strain types were distinguished. There was epidemiological evidence for selection of resistant strains derived from the host commensal flora and also for cross-colonization, and cross-infection. Carriage of resistant strains fell to 15% of patients, 6 months after the use of ciprofloxacin had ceased.


Neuron addition in the postmetamorphic frog. Neuron number among somatic motoneurons, sensory neurons, and sympathetic postganglionic neurons that innervate the hindlimb was correlated with body length in the bullfrog, Rana catesbeiana. Two to three times more dorsal root and sympathetic ganglion neurons are found in the largest than the smallest specimens. Hindlimb motoneurons show a 20% increase in number, but this increase is restricted to the caudal third of the motor pool. Within this region, 60% more motoneurons are found among the largest frogs. Cell division does not appear to be the mechanism of neuron addition. Instead, we propose that a pool of undifferentiated neurons mature to maintain functional capabilities as the animal increases in size.


Aging and the neurocytoskeleton.

Aging and the neurocytoskeleton. It has been often demonstrated that during senescence some neurons undergo atrophic changes while others add new processes and terminals. Because microtubules form a substantial component of the dendritic and axonal cytoskeleton, we have studied the amount of tubulin and acetylated alpha-tubulin in three young (6 months) and three old (24 months) rats (Fischer 344). We have used sodium dodecyl sulfate (SDS) extracts of brain homogenates and Triton solubilized fractionated brain homogenates. With the first method we did not detect any age-related differences in total brain protein, total tubulin, or in relative amounts of acetylated alpha-tubulin. With the second method, we have observed a small systematic increase in relative amount of acetylated alpha-tubulin in the Ca2+/cold insoluble fraction. These results are similar to those reported in the literature, and they indicate a possible alteration in the cytoskeletal dynamics.


Insect systems for the study of programmed neuronal death. In the moth Manduca sexta and the fly Drosophila melanogaster, the emergence of the adult is followed by a period of neuronal death. The steroid hormones, the ecdysteroids, are involved in two aspects of this death. Ecdysteroid action early in metamorphosis is somehow essential for fixing the fates of the neurons that will die. The actual triggering of their death, however, occurs a few weeks later and requires the withdrawal of the steroid and, at least in some cases, a trans-synaptic signal. These "execution" events involve both RNA and protein synthesis and result in the onset of degeneration about 10 h later. The early "decision" of a neuron to opt for the degeneration fate is associated with an altered pattern of ecdysteroid receptor expression. A model is presented to relate how the levels of steroid receptors may be related to the activation of death-related genes.


Calcium as sculptor and destroyer of neural circuitry. This paper examines the hypothesis that intracellular calcium plays guiding roles in the formation and adaptive modification of neural circuits in development and adult plasticity and that imbalances in calcium regulation lead to the degeneration of neural circuits in aging and disease. The neuronal growth cone is the motile structure largely responsible for the generation of neuroarchitecture. Studies of developing neurons in culture demonstrated that environmental signals believed to play key roles in neural development (i.e., neurotransmitters and growth factors) regulate growth cones by altering neuronal calcium-regulating systems. Different components of neurite outgrowth (i.e., neurite elongation and growth cone motility) are based upon different cytoskeletal systems (microtubules and microfilaments) which are differentially affected by calcium. In addition, cytoskeleton-associated proteins such as tau and microtubule-associated protein 2 (MAP2) are likely candidates for regulation by calcium. "Natural" neuronal death in development may occur as the result of growth factor deficiency or excess excitatory activity leading to sustained elevations in intracellular calcium levels. With aging and in disease, a loss of calcium homeostasis may underlie the aberrant neurodegeneration that occurs. For example, neurons subjected to conditions (e.g., glutamate and beta-amyloid) that cause sustained rises in intracellular calcium exhibit changes in the cytoskeleton similar to those seen in neurofibrillary tangles of Alzheimer's disease and related disorders. Taken together, the data suggest that cellular systems for calcium homeostasis are integral to both the adaptive and aberrant neuroarchitectural changes that occur throughout the lifespan of the nervous system.


Age-dependent alterations of synaptic performance and plasticity in crustacean motor systems. Age-related changes in synaptic performance and plasticity are surveyed in crustacean neuromuscular systems. These systems are functionally differentiated into phasic and tonic types, with different attributes of synaptic function and plasticity. Conversion of phasic neuromuscular junctions to a more phasic phenotype can be brought about by altering the activity of selected neurons. This type of plasticity disappears in older animals in some motor neurons, but is retained in others. Developmental programs set constraints on the age-dependent modifications of plasticity. Crustacean motor neurons are often characterized by great longevity, with progressive addition of new branches and synapses to keep up with growth of innervated muscle cells. Certain age-related compensatory mechanisms found in neuromuscular junctions of other species may not be required in crustaceans.


Age-related remodeling of lobster neuromuscular terminals. Multiterminal innervation of a lobster limb muscle by an identified excitor motoneuron was examined during primary development and adult growth. To keep pace with the growth in the target muscle, axonal branches proliferate by sprouting from synaptic terminals; an increasingly complex branching pattern results. Neuromuscular synapses multiply in number, enlarge in size, and become perforated. Concomitantly, synapses tend to appear on the more distal axonal branches and to disappear on more proximal branches, providing for continual remodeling of multiterminal innervation. This plasticity in an identified motoneuron occurs over a long life span of several decades.


Compensatory plasticity of aging at the neuromuscular junction. Several age-related phenomena observed at the neuromuscular junction (NMJ) can be viewed as adaptations to cellular deficits. These compensatory mechanisms, which maintain functional and morphologic integrity, are those present in the adult animal. In the study of compensatory mechanisms with age, the choice of an appropriate animal model is important. Three adaptations are discussed: maintenance or increase of transmitter release despite reduced supply of synaptic vesicles; functional reactive sprouting after partial denervation despite reduced axonal transport; and maintenance of nerve terminal integrity in the face of increased outgrowth and retraction. In all cases, successful adaptation in old animals is obtained at the expense of a more fragile system. Either the compensations themselves or the resulting vulnerability may alter the reactions of the aging nervous system to changes in external and internal milieu.


Differences in aging in two neural pathways: proposed explanations from the nervous system of Aplysia. A basic question in studies of the neurobiology of aging is to what extent age-related changes are genetically preprogrammed or epigenetically mediated. Our approach to this question is to compare the effect of age on two neural pathways in the marine mollusc, Aplysia. The advantage of Aplysia as a model of neural aging is that age-sensitive properties in the pathways can be studied at the behavioral, physiological, and morphological levels. The two pathways we are investigating respond differently to aging; a comparison of the pathways' properties provides a means of distinguishing the effect of age from other variables in the same animal. Age effects are expressed in the gill withdrawal reflex pathway at the three levels but are minimal in the gill respiratory pathway. The behavioral and physiological expressions of the reflex pathway are weakened in old animals (250 days of age and older) when compared to those in mature ones (ca. 160 days of age). The major differences between the two pathways are: (1) the reflex pathway appears to exhibit more plasticity than the respiratory pathway, and (2) the level of use of the respiratory pathway is more regular and frequent than that of the reflex pathway. The greater plasticity intrinsic to the reflex pathway and its level of use may well be the characteristics upon which age-related changes depend. An interplay between genetic and epigenetic factors is suggested to help explain the differential aging in the two pathways.


Hormonally-induced alterations in synaptic organization in the adult nervous system. In recent years, there is growing evidence that vertebrate neural circuits involved in reproduction retain a considerable amount of plasticity in adulthood. Gonadal steroid hormones cause dramatic changes in the synaptic organization of these circuits to regulate the expression of reproductive behavior. Two model systems are described to illustrate such changes: the neural system controlling song in passerine birds, and the spinal nucleus of the bulbocavernosus system in the rat spinal cord.


Neuronal migration on laminin involves neuronal contact formation followed by nuclear movement inside a preformed process. Neuronal migration was investigated in rodent cerebellum in vitro and in vivo. Time-lapse video recording showed that cultured neurons migrated on laminin by first extending neurites that formed contacts with other neurons. This was followed by movement of the cell nucleus inside the preformed process. No guidance cues other than laminin were required. When the rodent premigratory (E18-P0) cerebellum was examined by immunocytochemistry, the radial glial cells were found to have extracellular punctate deposits of laminin along their fibers. Such punctate deposits of laminin were more numerous in the premigratory cerebellum than during the peak of neuronal migration (e.g., at 7-10 days postnatally). At the same time (E18-P0) L1 antigen- and neurofilament-positive, presumably granule cell processes extend radially from the external granule cell layer (EGL). These results imply that neuronal migration on laminin in vitro involves neuronal contact formation followed by nuclear movement inside a preformed process. That this mode of neuronal migration may occur in vivo is indicated by the fact that L1 antigen- and neurofilament-positive "pioneer neurites" colocalize with the punctate deposits of laminin deposited along the radial glial processes in the premigratory EGL. Taken together these results imply that the established glial dependency of the granule cell migration may in fact be dependency of the granule cells and their pioneer neurites on the punctate deposits of laminin produced and laid down by the glial cells.


Persistent innervation of the rat neocortex by basal forebrain cholinergic neurons despite the massive reduction of cortical target neurons. I. Morphometric analysis. In Alzheimer's disease, a characteristic neurochemical abnormality is the loss of cholinergic enzymes in the neocortex, reflecting the degeneration of basal forebrain neurons responsible for cholinergic innervation of the neocortex. It is hypothesized that basal forebrain neuronal degeneration results from a reduction in the level of trophic factors synthesized by neurons in the target regions of cholinergic projections. Data from a large number of animal lesioning studies tend to support this theory; however, most of these lesions also induce widespread, nonspecific injury responses in the CNS. To directly test the dependence of basal forebrain cholinergic neurons on target-derived neurotrophic support, pregnant Sprague-Dawley rats were injected with moderate doses of methylazoxymethanol acetate (MAM) on Gestational Days 14 and 15. Extensive morphometric analysis of offspring reveals that the prenatal administration of MAM during this period of neurogenesis results in the ablation of 40-70% of cortical neurons, without significant effects on the hippocampus or the genesis of basal forebrain cholinergic neurons. Examination of MAM-treated animals at several ages reveals no significant differences in neuronal density of cholinergic neurons as compared to controls. Extensive analysis of animal brains at several time points has failed to reveal any evidence of classical injury responses which might be responsible for preservation of basal forebrain neurons. These results contradict the theory that mature basal forebrain cholinergic neurons are critically dependent on the availability of target-derived neurotrophic factors and are therefore unlikely to be the major etiological factor in basal forebrain neuronal degeneration characteristic of Alzheimer's disease.


Changes in brain polyamine levels following head injury. The changes in polyamines levels in the brain after closed head injury were studied in rats. At 1 and 15 min, 24 and 48 h after closed head injury cortical tissue from the site of injury, from the contralateral region, and from remote areas were taken. The levels of the diamine putrescine and the polyamines spermine and spermidine were assayed by thin layer liquid chromatography of their dansyl derivatives. Head injury induced a significant increase in putrescine at 48 h at the site of injury and in the frontal lobe of the injured hemisphere, respectively. In the contralateral hemisphere only minor changes in putrescine were found. Spermine and spermidine showed minor changes at that time course. We have previously shown that at 24-48 h after injury, severe edema is found at the site injury. In order to study the role of putrescine in edema formation in this model we treated the traumatized rats with alpha-difluoromethyl-ornithine (DFMO), an inhibitor of ornithine-decarboxylase, the rate limiting enzyme in putrescine biosynthesis. This drug did not affect the level of edema 4 or 48 h after injury although it abolished the increase in putrescine. The effect of DFMO on blood-brain barrier function was studied, using Evans blue extravasation, at the early post-traumatic period (15 min-4 h), where a massive amount of dye is taken up by traumatized brain. No changes in the amount of dye extracted was found after DFMO treatment. On the other hand, DFMO had a beneficial effect on the neurological outcome, as evaluated by a set of clinical criteria.(ABSTRACT TRUNCATED AT 250 WORDS)


Activity of ornithine decarboxylase and S-adenosylmethionine decarboxylase in transient cerebral ischemia: relationship to the duration of vascular occlusion. Mongolian gerbils were anesthetized with halothane and forebrain ischemia was induced by occluding both common carotid arteries. After 2, 4, 6, 8, or 10 min of vascular occlusion clips were removed and animals allowed to recover for 8 or 24 h. At the end of the experiments animals were reanesthetized and their brains frozen in situ. Tissue samples were taken from the cerebral cortex, striatum, hippocampus, and thalamus for determination of ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (SAMDC) activity by measurement of the release of 14CO2 from [14C]ornithine and S-[14C]adenosylmethionine, respectively. A transient increase in ODC activity was found after 8 h of recirculation following cerebral ischemia in all brain structures studied. ODC activity was significantly increased after 8 h of recirculation in the hippocampus of animals subjected to 4 min of ischemia, in the cortex and striatum after 6 min of ischemia, and in the thalamus after 8 min of vascular occlusion. ODC activity had already reached a plateau in the hippocampus after 4 min of vascular occlusion and in the cortex, striatum, and thalamus after 8 min, since there is no further increase in activity even after 10 min of ischemia. After cerebral ischemia and 24 h of recirculation ODC activity returned to control levels throughout the forebrain regardless of the duration of ischemia. SAMDC activity was significantly reduced after 8 h of recirculation following 4 to 10 min of ischemia in the cortex and 8 min of ischemia in the striatum.(ABSTRACT TRUNCATED AT 250 WORDS)


Analgesic and aversive effects of naloxone in BALB/c mice. Opioid antagonists have been shown to produce dose-dependent analgesia in the formalin test in BALB/c mice. In light of this paradoxical finding, the motivational-affective property of naloxone was examined in BALB/c mice. Naloxone produced a conditioned place aversion at doses which were also found to produce analgesia in the formalin test (1 and 10 mg/kg). In addition, the analgesia produced by 1 mg/kg naloxone was completely abolished in mice pretreated with nor-binaltorphimine, a highly selective kappa-opioid antagonist. Norbinaltorphimine on its own, however, had no effect. These results suggest that the analgesic actions of naloxone may be due to an interaction with kappa receptors.


Investigation of how different filters affect some biochemical properties of stored platelet concentrates. The aim of the present study was to investigate how four different filters, i.e. Imugard IG500 (Terumo, Japan), Miropore (Miramed, Italy), Pall P1-100 (Pall, USA) and Sepacell P1-10A (Asahi, Japan) affect some biochemical properties of platelet concentrates. The work was conducted using 42 pairs of platelet concentrates. After 2 days of storage, one of the preparations was filtered and the other served as an unfiltered control. Immediately after filtration, determination of the platelet count, desarginated activated complement factor 3 (C3a des arg) and the extracellular and total concentrations of platelet factor 4 (PF4) and lactate dehydrogenase (LDH) were carried out on both these platelet concentrates. After an additional storage period of 3 d, extracellular concentrations of PF4 and LDH were determined on both concentrates. A significant decrease of extracellular PF4 concentration was found immediately after filtration when Pall P1-100 and Imugard IG500 were used. During the 3-d storage after filtration, the concentrates filtered with Imugard IG500 and Pall P1-100 demonstrated significantly higher platelet lysis as compared to the unfiltered controls. It is concluded that the present work demonstrates storage instability after filtration with Imugard IG500 and Pall P1-100. Therefore, platelet concentrates filtered with these filters would not appear to be suitable for storage.


Normal mouse serum-derived factor(s) which inhibits growth of the interleukin-2-dependent cell line CTLL. Evidence is presented for the existence of a serum factor(s) (SF), which inhibits the growth of both the interleukin-2 (IL-2)-dependent cell line CTLL and the 2-day generation of CTL cells. This activity is found in the serum of both nude and euthymic mice and its suppressive effect can be detected about 18 hours after addition to CTLL cultures. The inhibitory activity elutes from a Sepharose 6B gel after the gamma globulin fraction (100-150 kD), and is precipitated by ammonium sulfate at 60 w/v% saturation. IL-3-mediated bone marrow colony formation is not inhibited by SF. It also does not suppress the growth of a panel of different tumor cell lines. The spleen cell responsiveness to both Con A and LPS activation is greatly reduced in the presence of SF. However, binding of radiolabelled IL-2 to CTLL cells was not blocked by SF, although the activity was greatly reduced by absorption to these cells. Our data support the existence of factor(s) in sera that may have a regulatory role on IL-2-mediated functions.


DDAVP-induced enhancement of platelet retention: its dependence on platelet-von Willebrand factor and the platelet receptor GP IIb/IIIa. Although DDAVP has been shown to be haemostatically efficacious in patients with various congenital or acquired platelet disorders, no reasonable explanation has been found for this effect. We have previously shown DDAVP to increase platelet adhesiveness as measured with a platelet retention test. The aim of the present study was to investigate the mechanism of action responsible for the increased platelet retention in response to DDAVP. Patients with vWD type III and type Ia, severe haemophilia and severe thrombasthenia, as well as healthy controls, were included in the study. The effect of different concentrations of vWF in plasma and platelets was explored, as was the effect on platelet function of apyrase and monoclonal antibodies against GP IIb/IIIa and GP Ib. We found the effect of DDAVP on platelet retention to be unaffected by changes in the plasma concentration of vWF. The enhanced platelet retention after DDAVP is apparently dependent on the presence of platelet-vWF and on a normal function of the GP IIb/IIIa. The effect is not mediated via ADP or thrombin. The platelet-stimulating effect of DDAVP may be one explanation for the positive haemostatic effect in patients with certain platelet disorders.


Smoking-induced changes in epithelial lining fluid volume, cell density and protein. Bronchoalveolar lavage has proved a useful research technique for recovering cellular and molecular contents of the lower respiratory tract. Because the recovered fluid is variably diluted, an accurate estimation of molecular and cellular concentrations can only be made if the epithelial lining fluid volume recovered is also known. It has been suggested that smoking may alter epithelial lining fluid volume by reducing clearance or by stimulating production and, thus, affect the interpretation of bronchoalveolar lavage studies. In this study, urea was used as an endogenous marker of epithelial lining fluid volume in a comparison of 26 smokers and 31 nonsmokers. The mean epithelial lining fluid volume recovered from smokers was significantly greater than that of nonsmokers (2.4 +/- 1.40 ml vs 1.2 +/- 0.75 ml, p less than 0.005). The total cellular concentration in the bronchoalveolar lavage fluid in smokers was also greater (94.2 +/- 46 x 10(6) vs 33.9 +/- 21.5 x 10(6) cells per 300 ml lavage), even when corrected for bronchoalveolar lavage volume recovered (63.1 +/- 32.5 x 10(6) vs 24.9 +/- 13.3 x 10(6) cells per 100 ml recovered lavage fluid). This was true for macrophage, lymphocyte and neutrophil cell numbers. However, when corrected for the apparent epithelial lining fluid volume, only the macrophage count remained significantly higher in the smokers compared with nonsmokers (30.66 +/- 20.7 x 10(6) vs 18.21 +/- 8.6 x 10(6) macrophages.ml-1 ELF). In addition, concentrations of albumin and immunoglobulin M (IgM) were significantly lower in smokers after correction for epithelial lining fluid volume. These results highlight smoking as a confounding factor in the interpretation of bronchoalveolar lavage data.(ABSTRACT TRUNCATED AT 250 WORDS)


Radiation-induced increase in hyaluronan and fibronectin in bronchoalveolar lavage fluid from breast cancer patients is suppressed by smoking. Bronchoalveolar lavage (BAL) fluid was analysed from 21 patients with breast cancer, stage T1N0M0, who had undergone tumour resection and post-operative local irradiation (accumulated dose 56 Gy). The lavage was performed two months after radiotherapy, in the anterior part of the lingula (left side) or of the right middle lobe (right side), depending on which side had been exposed to radiation. The patients had significantly increased concentrations of fibronectin (FN) (p less than 0.001), hyaluronan (HA) (p less than 0.01) and albumin (p less than 0.05) in BAL fluid compared with the healthy controls (n = 19). However, when the patients were separated, according to smoking history, it was obvious that the inflammatory reaction occurred entirely in the nonsmoking patient group (n = 10), whilst no difference could be found between the smoking patients (n = 11) and the controls. In the nonsmoking patient group, there was a sevenfold increase in BAL concentrations of FN and a threefold increase in HA. Moreover, four patients had detectable levels of procollagen III peptide in BAL, all were nonsmokers. The smoking habits of the controls had no influence on the BAL measurements. These findings indicate that smoking interferes with the radiation-induced early inflammatory connective tissue reaction of the lung. Finally, the results justify further investigation of interaction of smoking with cancer treatment, both from the view of therapy effectiveness and reduction of adverse effects.


Bronchiolitis obliterans organizing pneumonia (BOOP): the cytological and immunocytological profile of bronchoalveolar lavage. The cytological and immunocytological profile of bronchoalveolar lavage (BAL) was studied in 10 patients with idiopathic bronchiolitis obliterans organizing pneumonia (BOOP) and compared with the data in idiopathic pulmonary fibrosis (IPF) (n = 22), chronic eosinophilic pneumonia (CEP) (n = 9), and extrinsic allergic alveolitis (EAA) (n = 24). Lymphocyte subsets were enumerated using an immunoperoxidase slide assay. The BAL pattern in BOOP patients was characterized by several features: 1) colorful cell differentials with an increase in all cell types, most markedly in lymphocytes, and more moderately in neutrophils, eosinophils and mast cells, as well as the presence of foamy macrophages and, occasionally, of plasma cells; 2) decreased CD4/CD8 ratio; 3) normal percentage of CD57+ cells; and 4) increase in activated T-cells in terms of human leucocyte antigen-DR (HLA-DR) expression, and occasionally also interleukin-2 receptor (CD25) expression. The findings were most similar to those in EAA except for the CD25 expression, which was always normal, and the CD57+ cells, which were increased in EAA. The increase in lymphocytes discriminated best between BOOP and IPF. The eosinophils were significantly higher in CEP than in BOOP with little overlap. In conclusion, BAL may be of value to distinguish between BOOP and other interstitial lung disease.


Semi-quantitative X-ray microanalysis of bronchoalveolar lavage samples from silica-exposed and nonexposed subjects. To evaluate the possibility of quantifying alveolar dust burden in conditions of exposure to silica, four groups of subjects were submitted to bronchoalveolar lavage (BAL): 10 healthy control subjects and 39 patients affected by diffuse interstitial lung disease (DILD) never exposed to dust, 23 silicotic patients and 12 chronic bronchitis patients with a history of occupational exposure to silica dust. Five to ten million BAL recovered cells were analysed with an energy-dispersive X-ray microanalysis (EDXA) system to determine the silicon content, expressed in a semi-quantitative way as silicon to sulphur (Si/S) ratio. The results were independent of smoking habit. The Si/S median values (interquartile range in brackets) for the four groups were 0.53 (0.5-0.65), 0.60 (0.41-0.8), 1.23 (1.06-1.39), 1.31 (1.11-1.97), respectively. Silicotics and simply exposed individuals did not show a significant discrepancy, but they were both significantly different in comparison with normal and DILD patients without history of exposure (p less than 0.001). 14.3% false negative cases were found, and 4.1% false positive cases (none among normal subjects). We did not see any significant relationships between the amount of silicon and the duration of exposure or the degree of chest X-ray involvement. A study of cytocentrifuge slides from the same subjects by polarizing light microscopy revealed a lower sensitivity (34% false negative cases).(ABSTRACT TRUNCATED AT 250 WORDS)


Parenteral administration of trypsin triggers lung emphysema. Eight weeks after a single intravenous injection of trypsin, more than half of 26 treated rats showed pulmonary emphysema, as demonstrated by a significant increase of the mean linear intercept (MLI = 107 microns) in comparison with 11 controls (69 +/- 15 microns) (mean +/- SD). As observed 56 days after the injection, the intraperitoneal administration of trypsin (24 rats) also leads to lung emphysema (MLI = 101-106 microns), as does endotracheal instillation of elastase (13 rats), (MLI = 108 microns). The intraperitoneal administration of trypsin in animals constitutes a model close to human pathology with which lung alterations in acute pancreatitis may be studied. Having no elastolytic properties, trypsin cannot directly induce emphysema. The observation of a pulmonary leucostasis in eight rats sacrificed early after the trypsin injection suggested that leucocyte trapping and activation are important for the genesis of this trypsin-triggered emphysema.


Ultrastructural and immunohistochemical studies on the ontogenic development of bronchus-associated lymphoid tissue (BALT) in the rat: special reference to follicular dendritic cells. The ontogenic development of lymphoid and non-lymphoid cells in bronchus-associated lymphoid tissue (BALT) of the rat was studied ultrastructurally and immunohistochemically. In the late foetal period, only the alveolar macrophages showed a weak positivity for leucocyte common antigen, but no immune region associated (Ia) antigen was detected by monoclonal antibody, MAS 043. Mast cells were present. At 6 days of age, Ia-positive cells were observed in the alveolar wall and peribronchial interstitial tissue, and ultrastructurally there was an aggregation of the fibroblastoid mesenchymal cells. By 10 days of age, the aggregation of lymphoid cells together with S-100-positive reticulum cells had formed a BALT-like periarterial lymphoid sheath. In the adult animals, an obvious B-cell area was present in the central part and subepithelium of BALT, whilst in this area, S-100-positive, strongly Ia-positive cells with a dendritic form were observed. These dendritic cells appeared to be identical to the follicular dendritic cells (FDC) seen in the secondary follicles of lymphoid organs. Those cells may be derived from the fibroblastic reticulum cells, and may function to present antigen to lymphocytes.


Bronchial responsiveness and work-related asthma in aluminium potroom workers: effect of removal from exposure. Twelve subjects relocated from aluminium potrooms due to work-related asthma were followed up for 2-27 months (median 23 months). Repeated post-relocation examinations (numbering 3-7, median 6) of methacholine challenge, forced expiratory volume in one second (FEV1), eosinophil cell count and respiratory symptoms were carried out at regular intervals. At the time of relocation, bronchial hyperresponsiveness (provoking concentration producing a 20% fall in FEV1 (PC20) less than or equal to 8.0 mg.ml-1) was found in eight of the subjects. During the follow-up period a twofold increase in PC20 was found in 7 of the 8 subjects who had PC20 less than 8.0 mg.ml-1 at the time of relocation. There was an improvement of symptoms but no improvement in FEV1 or decrease of eosinophils during the follow-up examinations.


Diurnal variation in FEV1 after heart-lung transplantation. We have examined the diurnal variation in forced expiratory volume in one second (FEV1) in 25 heart-lung transplantation patients over a four week period in order to study the pathophysiological mechanisms underlying the increased mortality and morbidity which occurs at night in asthma. These patients do not have pulmonary autonomic nervous reflexes, but often have muscarinic receptor hypersensitivity. They also develop mixed cell infiltration of the lung tissue in the course of infection or rejection. Thus, they show many features in common with asthma. Seventeen patients (68%) showed a significant diurnal variation in airway calibre (mean amplitude of FEV1 was 4.6% (SD 3.7%)), which is similar to that reported in normal adults. One patient had a diurnal variation of 34.5% during an episode of rejection. This variation fell to 6.9% after steroid therapy, a change often seen in asthma. There was a correlation between increased amplitude of the variation and the presence in transbronchial biopsies of airway submucosal eosinophils and lymphocytes, associated with a histological diagnosis of acute rejection and with epithelial damage. No association was seen with muscarinic receptor sensitivity. The variation in FEV1 showed no alteration from the normal day/night synchronization, and the peak values were around 1300 h. We conclude that the diurnal variation in FEV1 after heart-lung transplantation is not dependent on autonomic nerve reflexes or muscarinic receptor sensitivity, but is related to the consequences of inflammation described above.


Adaptation of cough reflex with different types of stimulation. Inhalation cough challenge has become an accepted method of investigating antitussive agents. It is, therefore, important to examine the degree of tachyphylaxis seen with repeated cough challenge. In addition, different types of challenge may reveal important differences in the neuronal pathways involved in the cough reflex. Citric acid, distilled water and capsaicin were examined to determine adaptation of the cough response during acute and long-term inhalation studies in healthy subjects. To study acute tachyphylaxis two separate one minute continuous inhalation challenges (n = 13) were performed. Long-term tachyphylaxis (n = 10) was examined using citric acid and capsaicin inhalation at 10 min intervals for 40 min, and at 4 and 6 h. Cross-tachyphylaxis to citric acid and capsaicin was examined in a separate randomized crossover study (n = 10). Highly significant adaptation occurred between the first and last 10 s of the one minute challenge with citric acid (90-100%) and distilled water (74-84%), but was less pronounced with capsaicin (37-49%, at 2 microM). Cough during the whole of the second test was significantly reduced for citric acid (50%). During long-term challenge cough was attenuated over 40 min both with citric acid (100 mM, p less than 0.05; 300 mM, p less than 0.001; 1 M, p less than 0.001) and with capsaicin (3 microM, p less than 0.01; 10, 30, 100 microM, p less than 0.001 each). With higher doses, tachyphylaxis was still present at 180 min with both citric acid (300 mM, p less than 0.05) and capsaicin (100 microM, p less than 0.008).(ABSTRACT TRUNCATED AT 250 WORDS)


Adherence to entry criteria and one year experience of long-term oxygen therapy in Poland. The adherence to entry criteria and results of one year long-term oxygen therapy (LTOT) in Poland were analysed. Four hundred and seven patients with advanced respiratory failure due to chronic lung diseases qualified for LTOT were observed for one year in 12 regional LTOT centres. There were 315 patients with chronic obstructive pulmonary disease (COPD) and 92 with other chronic lung diseases. In 270 patients the prescription of oxygen was based on the single criterion of stable arterial oxygen tension (PaO2) less than or equal to 55 mmHg (7.3 kPa); and in the remaining 137 with less severe stable hypoxaemia (PaO2 56-65 mmHg) (7.4-8.6 kPa), on concomitant signs of cor pulmonale and/or of tissue hypoxia. Of 407 patients who started LTOT, 95 (23%) died during the first year of treatment. The mortality rate was 21% for COPD patients and 33% for patients with other lung diseases. After one year of LTOT 312 patients survived: 250 COPD patients and 62 with other lung diseases. Of these, 19 COPD patients (8%) and 9 with other chronic lung disease (15%) who had PaO2 less than or equal to 55 mmHg (7.3 kPa) when oxygen was prescribed, presented with PaO2 greater than 55 mmHg (7.3 kPa). From the 137 patients (106 with COPD and 31 with other lung diseases) who qualified with less severe hypoxaemia, 10 COPD patients (10%) and 5 (16%) with other lung disease had PaO2 greater than 65 mmHg (8.6 kPa).(ABSTRACT TRUNCATED AT 250 WORDS)


Changes in heart rate during obstructive sleep apnoea. The mechanisms behind the decrease in heart rate during apnoeas in patients with obstructive sleep apnoea (OSA) are little known. Recent findings in animal experiments indicate that stimulation of the upper airway activates postinspiratory and cardiac vagal neurones in the medullary respiratory centre, causing alterations in heart rate and respiratory rhythm. Since OSA leads to a collapse of the airway and consequent stimulation of upper airway receptors, we studied the interrelations between heart rate and respiratory rhythm during apnoea and during negative intrathoracic pressure generated by the Mueller manoeuvre (MM). Fifteen patients with OSA (apnoea hypopnoea index (AHI) 45 +/- 28.h-1) were studied by polysomnography, during a MM and a Valsalva manoeuvre, each of 15 s duration. The heart rate decrease (delta HRA) and the increase in total respiratory cycle duration (TOT) were evaluated during apnoea in non-rapid eye movement (REM) sleep. Patients with OSA demonstrated a decrease in heart rate during apnoea (-14.4 +/- 9.0 beats.min-1), and during MM (-11.5 +/- 13.5 in OSA vs 3.1 +/- 7.8 beats.min-1 in a control group). TOT increased during apnoea (4.6 +/- 3.1 s). There was a significant correlation between delta HRA and AHI (r = -0.64) as well as between delta HRA and increase in TOT (r = 0.62). These findings indicate that upper airway obstruction may cause an activation of receptors at the site of airway collapse or distortion leading to changes in heart rate and respiratory rhythm.


Haemodynamic effects of short-term nasal continuous positive airway pressure therapy in sleep apnoea syndrome: monitoring by a finger arterial pressure device. We have evaluated the effects of short-term nasal continuous positive airway pressure (nCPAP) therapy on systemic blood pressure and heart rate in patients with obstructive sleep apnoea syndrome. Twenty five consecutive patients were examined during baseline conditions (No-CPAP) and during one night of nCPAP treatment (CPAP). The mean value and the variation coefficient of cardiovascular variables, examined by a finger arterial pressure device (Finapres), were determined in wakefulness and sleep. Without nCPAP an increase in blood pressure from wakefulness to sleep was observed in all patients from 138 +/- 3 mmHg to 146 +/- 3 and 155 +/- 4 mmHg, and from 80 +/- 1 mmHg to 82 +/- 2 and 84 +/- 2 mmHg, respectively, for systolic and diastolic values in non rapid eye movement (NREM) and rapid eye movement (REM) sleep. Conversely, heart rate decreased from 75 +/- 2 beats.min-1 to 70 +/- 2 and 69 +/- 2 beats.min-1. In addition, variability of heart rate and blood pressure was greatly increased compared with the awake state. Short-term nCPAP therapy significantly reduced systolic pressure from 144 +/- 3 mmHg to 137 +/- 3 and 143 +/- 4 mmHg during NREM and REM sleep, respectively, associated with a decrease in heart rate (from 69 +/- 2 to 65 +/- 2 beat.min-1). In total sleep and in all sleep stages a significantly reduced variability (p less than 0.001) was found. No changes were observed for diastolic pressure during CPAP night compared with baseline conditions.(ABSTRACT TRUNCATED AT 250 WORDS)


Respiratory function during wakefulness and sleep among survivors of respiratory and non-respiratory poliomyelitis. The purpose of this study was to determine whether there is a difference in respiratory mechanics and gas exchange between polio survivors and healthy, age-matched controls during wakefulness and sleep. Polio survivors were divided into four groups. The first group included those who had evidence of respiratory muscle involvement originally (PRM) and the second group included those who had bulbar muscle involvement originally (PBM). The third and fourth groups had only limb involvement originally but were separated by absence (PSL) or presence of a scoliosis (PSS) at the time of their evaluation. Each subject completed baseline and one year follow-up measurements of lung volumes, diffusion, flow rates, respiratory muscle strength, central and peripheral chemoreflexes and arterial blood gases. Sleep measurements included a full respiratory polysomnographic study. Fifty polio survivors and 13 controls completed the study. The PRM and PSS groups had an elevated arterial carbon dioxide tension (PaCO2) (mean +/- SE 6.0 +/- 0.4 and 6.0 +/- 0.3 kPa, respectively), reduced vital capacity (2.8 +/- 0.3 and 2.9 +/- 0.3 l, respectively), reduced maximal inspiratory pressure (-5.9 +/- 0.7 and -5.4 +/- 0.8 kPa, respectively) and reduced maximal expiratory pressure (9.8 +/- 1.1 and 9.1 +/- 1.2 kPa, respectively), when compared with non-polio controls. During sleep PRM and PSS groups experienced a higher PaCO2 (6.5 +/- 0.5 and 6.7 +/- 0.4 kPa, respectively) and a lower arterial oxygen saturation (SaO2) (89 +/- 4 and 86 +/- 3%, respectively). There were no differences among groups for diffusion, flow rates and chemoreflexes. All other polio survivors showed essentially normal respiratory function.(ABSTRACT TRUNCATED AT 250 WORDS)


Respiratory mechanics studied by multiple linear regression in unsedated ventilated patients. Respiratory mechanics during artificial ventilation are commonly studied with methods which require a specific respiratory pattern. An alternative is to analyse the relationship between tracheal pressure (P) and flow (V') by multiple linear regression (MLR) using a suitable model. The value of this approach was evaluated in 12 unsedated patients, mechanically-ventilated for acute respiratory failure, and most with a history of chronic obstructive or restrictive respiratory disease. After correction for the non-linear resistance of the endotracheal tube, the data were analysed with the linear first order model: P = P0 + E.V + R.V' where E and R are total respiratory elastance and resistance, and P0 is the static recoil pressure at end-expiration. After exclusion of the cycles which clearly exhibited muscular activity, a good fit was observed in 25 out of 36 records (relative root-mean-square error less than 10%); the values of E and R were reproducible within cycles, and consistent with the patient's condition and the ventilatory mode. The intrinsic positive end-expiratory pressure (PEEPi), as derived from P0 and the applied PEEP, averaged 1.1 +/- 1.0 hPa. Using more sophisticated models, allowing for mechanical non-homogeneity or non-linearity of R or E, rarely improved the fit and often provided unrealistic data. In several subjects the discrepancy between the data and the first order model was consistent with expiratory flow limitation, which may severely impair the analysis. We conclude that, except in the case of expiratory flow limitation, the method is useful for routine clinical use and better implemented with the simple linear model.


Lung volumes measured by the forced rebreathing technique in children with airways obstruction. Forced rebreathings may recruit trapped gas into the mixing process. Therefore, we assessed the validity and reproducibility of measurements of residual volume (RVN2) by forced rebreathing in a closed circuit using N2 as indicator gas (N2FR) in children with airways obstruction. Validity was studied from measurements of RV obtained by N2FR, by helium dilution during resting ventilation, and by body plethysmograph at low panting frequency in young patients (8-18 yrs, 13 with asthma, forced expiratory volume in one second (FEV1) 93.0 +/- 22.8% pred; 12 with cystic fibrosis (CF), FEV1 80.4 +/- 16.4% pred). Reproducibility of RVN2 was assessed from duplicate measurements in 73 patients with asthma before and after bronchodilation (FEV1 81.4 +/- 13.7 and 99.6 +/- 11.5% pred, respectively), and in nine patients with CF; the total lung capacity (TLC) was unaffected by bronchodilation; 3,797 +/- 830 ml and 3,807 +/- 843 ml, respectively. Gas dilution methods gave comparable results in all subjects but gave lower values than plethysmography in patients with cystic fibrosis. Reproducibility was satisfactory, median differences between duplicate measurements of RVN2 and TLCN2 varying between 13 and 46 ml, respectively. We conclude that N2FR is quickly performed and well-tolerated. Lung volumes are highly reproducible and agree well with those obtained with the helium dilution method. Deep inspirations do not seem to overcome gas trapping in patients with CF.


Update on an exposure system for particles in the diagnosis of occupational asthma. We have previously designed a system for exposure to particles and described the preliminary results in 20 subjects exposed to occupational sensitizers in powder form (Cloutier Y, et al. - Eur Respir J, 1989; 2: 769). Modifications have been made to the particles generator, exposure chamber and sampling ports. Furthermore, in order to improve the stability of concentrations in the exposure chamber and to make the system easy to operate by a technician, it has been completely automated using closed-loop feedback regulated by a computer program.


Intraventricular rifampicin in severe tuberculous meningo-encephalitis. We present a patient acutely ill from severe tuberculous meningo-encephalitis, in whom acute hepatic and renal failure, due to intercurrent septic shock, precluded the administration of full systemic dosage of antituberculous drugs. Daily direct intraventricular administration of 5 mg rifampicin, via a subcutaneous Ommaya reservoir connected to a catheter placed in the right lateral cerebral ventricle, resulted in rapid improvement without neurological sequelae. Intraventricular rifampicin administration for 50 consecutive days was well-tolerated without local or systemic side-effects. In well-selected patients with severe tuberculous meningo-encephalitis, intraventricular rifampicin may safely and highly effectively be added to systemic antituberculous therapy.


Progesterone action through aggregation of a receptor on the sperm plasma membrane. Rapid steroid effects, reported in several cell types, have pointed out the possibility of non-genomic mechanisms of action, presumably on cell surface receptors. Here we analyzed the effects of antibody-mediated aggregation of a novel type of progesterone receptor on the plasma membrane of human sperm cells. We report that aggregation of hormone-receptor complexes induces Ca2+ influx and a Ca(2+)-dependent exocytotic event in this system. These data suggest a possible mechanism for rapid steroid-induced events. Further research is warranted to examined if a similar mechanism is involved in rapid steroid effects in other cell types.


Activation of protein kinase C by the 14-3-3 proteins homologous with Exo1 protein that stimulates calcium-dependent exocytosis. The 14-3-3 proteins are a family of acidic proteins found mainly in the brain and are suggested to have a role in monoamine synthesis based on their ability to activate tyrosine and tryptophan hydroxylases in the presence of type II Ca2+/calmodulin-dependent protein kinase. Recently, however, it has been demonstrated that a member of the 14-3-3 family, termed Exo1, stimulates Ca(2+)-dependent exocytosis in permeabilized adrenal chromaffin cells, suggesting that this protein family may influence the protein kinase C-mediated control of Ca(2+)-dependent exocytosis. Here we show that the 14-3-3 proteins activate protein kinase C at about 2-fold more than the known level of the activated protein kinase, i.e. the activity of protein kinase C in the presence of Ca2+ and phospholipids. This raises the possibility that the cellular activity of protein kinase C is regulated by diverse members of the 14-3-3 family and that the reported ability of Exo1 to reactivate Ca(2+)-dependent exocytosis is based on its stimulatory effect on protein kinase C activity. The 14-3-3 family, therefore, appears to be a multifunctional regulator of cell signalling processes mediated by two types of Ca(2+)-dependent protein kinase, protein kinase C and type II calmodulin-dependent protein kinase.


Over-expression of human phospholipase C-gamma 2 enhances platelet-derived growth factor-induced mobilization of intracellular Ca2+ and the release of arachidonic acid and prostaglandins in NIH 3T3 fibroblasts. Over-expression of human phospholipase C-gamma 2 in murine NIH 3T3 fibroblasts has been shown to result in an increased platelet-derived growth factor-mediated formation of inositol phosphates. Here we show that phospholipase C-gamma 2 over-expression is associated with an increased platelet-derived growth factor-mediated release of arachidonic acid, prostaglandin E2, 6-keto prostaglandin F1 alpha and prostaglandin F2 alpha. The phorbol ester, calcium ionophore- and fluoride-induced release of arachidonate and its metabolites is not affected by phospholipase C-gamma 2 over-expression. Over-expression of phospholipase C-gamma 2 is also associated with an enhancement of platelet-derived growth factor-induced change in intracellular Ca2+. These results demonstrate that stimulation of recombinant human phospholipase C-gamma 2 induces a change in the intracellular Ca2+ concentration, a release of arachidonic acid and formation of prostaglandins in NIH 3T3 cells. In control cells platelet-derived growth factor-induced activation of arachidonic acid cascade is rate-limited by the endogenous phospholipase C.


Purification and characterization of glycerol-3-phosphate dehydrogenase of Saccharomyces cerevisiae. The NAD-dependent glycerol-3-phosphate dehydrogenase (glycerol-3-phosphate:NAD+ oxidoreductase; EC 1.1.1.8; G3P DHG) was purified 178-fold to homogeneity from Saccharomyces cerevisiae strain H44-3D by affinity- and ion-exchange chromatography. SDS-PAGE indicated that the enzyme had a molecular mass of approximately 42,000 (+/- 1,000) whereas a molecular mass of 68,000 was observed using gel filtration, implying that the enzyme may exist as a dimer. The pH optimum for the reduction of dihydroxyacetone phosphate (DHAP) was 7.6 and the enzyme had a pI of 7.4. NADPH will not substitute for NADH as coenzyme in the reduction of DHAP. The oxidation of glycerol-3-phosphate (G3P) occurs at 3% of the rate of DHAP reduction at pH 7.0. Apparent Km values obtained were 0.023 and 0.54 mM for NADH and DHAP, respectively. NAD, fructose-1,6-bisphosphate (FBP), ATP and ADP inhibited G3P DHG activity. Ki values obtained for NAD with NADH as variable substrate and FBP with DHAP as variable substrate were 0.93 and 4.8 mM, respectively.


Investigation of spatial relationships and energy transfer between complexes B800-850 and B890-RC from Chromatium minutissimum reconstituted into liposomes. Spatial relationships between different pigment-protein complexes in the membranes of the purple photosynthetic bacterium, Chromatium minutissimum, have been studied. The possibility of restoring the function of efficient excitation energy transfer from bacteriochlorophyll molecules to the reaction centers in the system of soybean liposomes, reconstituted with pigment-protein complexes B800-850 and B890-RC from C. minutissimum, has been explored. The chemical cross-linking method, together with stationary and picosecond spectrally resolved fluorescence measurements were employed. It has been shown that after the incorporation of the complexes into the liposome membranes conditions for directed excitation energy transfer from the light-harvesting pigments to the reaction centers are created, which are less optimal, however, than those in the native state. Possible reasons are considered.


Effect of RU 38486 on TNF production and toxicity. Glucocorticoid steroids provide considerable protection against the systemic toxicity of tumor necrosis factor-alpha (TNF-alpha, cachexin). In animal experiments RU 38486 (mifepristone), a steroid antagonist, increased the synthesis of TNF and sensitized the animals to the cytotoxic action of TNF. As compared to the control and methylprednisolone-treated groups, mifepristone significantly increased the level of TNF in the serum, liver and spleen of lipopolysaccharide (LPS)-treated animals. In tissue cultures RU 38486 induced the TNF synthesis of myeloid cells and increased the TNF production of genetically modified HeLa cells, which synthesize TNF constitutively. Normal and tumor cell cultures exhibited increased sensitivity toward TNF in the presence of mifepristone.


Mapping and sequence-specific identification of phosphopeptides in unfractionated protein digest mixtures by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. We have demonstrated a procedure for the rapid (minutes), sensitive (less than pmol), and sequence-specific identification of phosphopeptides in unfractionated digests of phosphoproteins using matrix-assisted UV laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry. The mass-dependent identification of one specific 13-residue phosphopeptide (S105-K117), observed among the 153 possible trypsin digest fragments of human beta-casein (211 residues), was confirmed by amino acid sequence analysis of the 33P-labeled peptide after isolation by reverse-phase HPLC. MALDI-TOF was also used to monitor the rate and extent to which an 18-residue N-terminal beta-casein peptide (R1-K18) was phosphorylated in vitro. These results demonstrate that MALDI-TOF may be used (i) to facilitate the identification of sequence-specific sites of protein phosphorylation and dephosphorylation, (ii) to monitor protein and peptide phosphorylation and dephosphorylation reaction rates, even in complex unfractionated mixtures, (iii) to determine the minimum primary structure necessary for the phosphorylation of specific protein surface domains, and (iv) to evaluate the effects of intact protein phosphorylation and dephosphorylation on susceptibility to subsequent proteolytic events.


Glycoprotein-binding site of dystrophin is confined to the cysteine-rich domain and the first half of the carboxy-terminal domain. Dystrophin, a protein product of the Duchenne muscular dystrophy gene, is thought to associate with the muscle membrane by way of a glycoprotein complex which was co-purified with dystrophin. Here, we firstly demonstrate direct biochemical evidence for association of the carboxy-terminal region of dystrophin with the glycoprotein complex. The binding site is found to lie further inward than previously expected and confined to the cysteine-rich domain and the first half of the carboxy-terminal domain. Since this portion corresponds well to the region that, when missing, results in severe phenotypes, our finding may provide a molecular basis of the disease.


Characterisation of a human bilirubin UDP-glucuronosyltransferase stably expressed in hamster lung fibroblast cell cultures. A cDNA encoding a human bilirubin UDP-glucuronosyltransferase has been isolated and stably expressed in Chinese hamster V79 lung fibroblast cell line. Western blotting of cell homogenates with anti-UGT antibody revealed a highly expressed protein of approx. 55.5 kDa in size. The expressed enzyme specifically catalysed the formation of bilirubin mono- and diglucuronides, and also catalysed the glucuronidation of two phenolic compounds, which are good substrates for other human UGT isoenzymes, at low rates.


Protein synthesis in HL-60 cells treated with DMSO and hypoxanthine. Short-term treatment of the HL-60 cells with DMSO and hypoxanthine, inducers of granulocytic differentiation, was reported to cause a rapid increase in protein synthesis. This effect was ascribed to the insertion of inosine in the wobble position of the tRNA anticodon and consequently increasing codon recognition potential. In this study we have re-investigated the effects of DMSO and/or hypoxanthine on protein synthesis. In contrast to their findings we were unable to demonstrate stimulated protein synthesis in either short- or long-term treatment with these agents. Polysome analysis under these conditions revealed that polysomes were disaggregated. Finally, the activity of tRNA-hypoxanthine ribosyltransferase, an enzyme responsible for the insertion of inosine in the anticodon, was also relatively low. Under these circumstances, we propose that tRNA modification is not essential in the regulation of protein synthesis.


Human immunodeficiency virus type 1 productive infection in staurosporine-blocked quiescent cells. Staurosporine, an antibiotic known to inhibit cellular protein kinases, can reversibly block the progress of normal and tumour cells into the cell cycle. The ability of HIV-1 to infect and replicate in cells blocked by staurosporine was investigated. The results show that blocked, non-cycling cells can be productively infected by HIV-1, steadily releasing infectious progeny virus for several weeks. This suggests that at least in some cases, HIV-1 can be found in a stable and active state in resting, non-proliferating T cells.


Production and secretion of plasminogen in cultured rat brain microglia. The production and secretion of plasminogen in cultured rat brain microglia was investigated. Urokinase-dependent caseinolytic activity was detected by zymography in microglial conditioned medium with a molecular weight of about 90 kDa. The 90-kDa protein was also detected by Western blotting with anti-rat plasminogen antiserum in the non-reducing condition. Immunoprecipitation with plasminogen antiserum following [35S]methionine labelling revealed that the plasminogen detected in microglial conditioned medium is synthesized in microglia. The amount of plasminogen in the conditioned medium was increased by stimulation with lipopolysaccharide. These results show that cultured microglia produce plasminogen and secrete it into the culture medium.


MAP kinase kinase from rabbit skeletal muscle. A novel dual specificity enzyme showing homology to yeast protein kinases involved in pheromone-dependent signal transduction. MAP kinase kinase (MAPKK) was purified 30,000-fold to homogeneity from extracts of rabbit skeletal muscle and shown to be a monomeric protein of apparent molecular mass 44 kDa. MAPKK activated the 42 kDa isoform of MAP kinase by phosphorylation of Thr-183 and Tyr-185, and phosphorylated itself slowly on tyrosine, threonine and serine residues, establishing that it is a 'dual specificity' protein kinase. Peptide sequences from MAPKK were homologous to other protein serine/threonine kinases, especially to the subfamily that includes yeast protein kinases that lie upstream of yeast MAP kinase homologues in the pheromone-dependent mating pathways.


Reversal of oxidative phosphorylation in submitochondrial particles using glucose 6-phosphate and hexokinase as an ATP regenerating system. During steady-state, the Pi released in the medium is derived from glucose-6-phosphate which continuously regenerates the ATP hydrolyzed. A membrane potential (delta psi) can be built up in submitochondrial particles using glucose-6-phosphate and hexokinase as an ATP-regenerating system. The energy derived from the membrane potential thus formed, can be used to promote the energy-dependent transhydrogenation from NADH to NADP+ and the uphill electron transfer from succinate to NAD+. In spite of the large differences in the energies of hydrolysis of ATP (delta G degrees = -7.0 to -9.0 kcal/mol) and of glucose-6-phosphate (delta G degrees = -2.5 kcal/mol), the same ratio between Pi production and either NADPH or NADH formation were measured regardless of whether millimolar concentrations of ATP or a mixture of ADP, glucose-6-phosphate and hexokinase were used. Rat liver mitochondria were able to accumulate Ca2+ when incubated in a medium containing hexokinase, ADP and glucose-6-phosphate. The different reaction measured with the use of glucose-6-phosphate and hexokinase were inhibited by glucose concentrations varying from 0.2 to 2 mM. Glucose shifts the equilibrium of the reaction towards glucose-6-phosphate formation thus leading to a decrease of the ATP concentration in the medium.


Nerve growth factor rapidly regulates VGF gene transcription through cycloheximide sensitive and insensitive pathways. Nerve growth factor (NGF) initiates and maintains a regulatory cascade, involving gene induction, which results in the neuronal differentiation of PC12 cells. The VGF gene encodes one of the most rapidly induced neuronal mRNAs identified in NGF-treated PC12 cells [Science, 229 (1985) 393-395; Mol. Cell Biol., 11 (1991) 2335-2349]. In this communication we show that NGF-treatment for 60-90 min maximally increases VGF gene transcription by 12- to 14-fold. VGF mRNA half-life was found to substantially decrease in PC12 cells treated with NGF for 9-25 h. Partial inhibition of VGF gene transcription and superinduction of cytoplasmic VGF mRNA levels in the presence of both NGF and cycloheximide suggests that the VGF gene may be regulated through multiple pathways, some of which can be activated in the presence of protein synthesis inhibitors as are the immediate early genes, while others require newly synthesized proteins.


Rat liver BiP/GRP78 is down-regulated by a peroxisome-proliferator, clofibrate. Administration of clofibrate in rat results in down-regulation of several liver proteins and a vast induction of peroxisomal proteins. One protein was identified as BiP/GRP78 using antibodies and cDNA cloning. The level of mRNA was reduced by the drug.


Is the cytosolic catalase induced by peroxisome proliferators in mouse liver on its way to the peroxisomes? Dietary treatment of male C57B1/6 mice with clofibrate, nafenopin or WY-14.643 resulted in a modest (at most 2-fold) increase in the total catalase activity in the whole homogenate and mitochondrial fraction prepared from the livers of these animals. On the other hand, the catalase activity recovered in the cytosolic fraction was increased 12- to 18-fold, i.e. 30-35% of the total catalase activity in the hepatic homogenate was present in the high-speed supernatant fraction after treatment with these peroxisome proliferators. A study of the time course of the changes in peroxisomal and cytosolic catalase activities demonstrated that the peroxisomal activity both increased upon initiation of exposure and decreased after termination of treatment several days after the increase and decrease, respectively, in the corresponding cytosolic activity. This finding suggests that the cytosolic catalase may be on its way to incorporation into peroxisomes.


Phosphorescence and ODMR study of the binding interactions of acetylcholine receptor alpha-subunit peptides with alpha-cobratoxin. Optical detection of magnetic resonance (ODMR) and phosphorescence spectroscopy have been applied to synthetic peptides derived from the alpha-subunit of the nicotinic acetylcholine receptor of Torpedo californica and their complexes with alpha-cobratoxin (CBTX). The CBTX Trp phosphorescence is strongly quenched by the proximal disulfide linkage, while the emission wavelengths and ODMR frequencies of the 18-mer alpha 181-198 indicate a more hydrophobic Trp environment than in the 12-mer alpha 185-196. Binding to CBTX produces a subtle increase in the hydrophobicity of the Trp environment for the peptides, in qualitative agreement with a recently proposed binding model, in which a receptor Trp residue interacts strongly with a hydrophobic cleft of the toxin.


Endothelial cell injury secondary to surgical preparation of reversed and in situ saphenous vein bypass grafts. Failure of infra-inguinal vein grafts appears to be due to the development of intrinsic lesions (intimal hyperplasia, fibrous stenoses) within the graft which lead to narrowing of the lumen, poor blood flow and thrombosis. The cause of these lesions remains unknown but recently it has been suggested that endothelial injury might be an aetiological factor. The damage that can occur after preparation of reversed vein grafts includes loss of endothelial cells and functional impairment of those cells that remain, in that the ability to produce prostacyclin and endothelium-derived relaxing factor (EDRF) is reduced. The preparation of in situ grafts is different to that for reversed grafts in that a valvulotome is passed along the lumen of the vein to destroy the valves. However, little is known about the degree of endothelial injury that this technique causes. Vein samples were obtained from patients undergoing infra-inguinal and coronary artery bypass grafting. The veins were mounted in an organ bath system to measure isometric tension and exposed to the endothelium-dependent agents acetylcholine, bradykinin, adenosine, histamine and the endothelium-independent agent sodium nitroprusside. The results indicate that preparation of reversed vein grafts leads to some loss of endothelial cells with functional impairment of the cells that remain. However, preparation of in situ grafts leads to severe or total loss of endothelial cells which resulted in an absence of detectable EDRF release. These findings were confirmed by histological examination of the vein samples.


The effect of infrarenal aortic reconstruction on glomerular filtration rate and effective renal plasma flow. Compromised patients with aortic disease are vulnerable to various complications from aortic reconstruction. These complications are related to changes in systemic haemodynamics during aortic cross-clamping, which leads to cardiac stress and alteration in regional blood flow to different organs. One of the most important postoperative complications is renal failure which is associated with a high mortality rate. Circulatory alterations within the kidney must play a role in the pathogenesis of renal dysfunction that may follow infrarenal aortic cross-clamping and reconstruction. To study the effects of abdominal aortic reconstruction on renal function and perfusion, we measured prospectively the glomerular filtration rate (GFR, n = 59), effective renal plasma flow (ERPF, n = 38) and left ventricular ejection fraction (LVEF, n = 38) in patients undergoing elective infrarenal aortic reconstruction. Radionuclide techniques were used. The three parameters were measured at three time points: preoperatively, postoperatively and 6 months after surgery. The LVEF was measured in order to reflect the patient's cardiac status and pre-renal perfusion. We also measured the three parameters in two control groups of patients: a group of patients undergoing major colonic surgery and a group of patients with arterial disease under conservative management. Six months after surgery the GFR had decreased in 67% of aortic reconstruction patients. Overall GFR in the aortic reconstruction group decreased by a mean of 9 ml min-1 (p = 0.007). This was associated with a decrease in the ERPF in 48.5% of patients. The mean decrease in ERPF in the aortic reconstruction group was 74 ml min-1 (p = 0.05). The LVEF was unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)


The carotid stump syndrome.

The carotid stump syndrome. Transient ischaemic attacks (TIAs) following internal carotid artery occlusion are not uncommon. Micro-embolisation from an ipsilateral internal carotid artery stump has been implicated in the pathogenesis of such TIAs. We report six patients who had persistent TIAs in association with an occluded ipsilateral internal carotid artery and a carotid stump. Four patients who underwent surgery and stump exclusion remain asymptomatic at 2 years while of two patients who were treated with antiplatelet therapy, one remains asymptomatic and one died from a cerebro-vascular accident.


Ultrastructural analysis of pseudo-intimal hyperplasia of polytetrafluoroethylene prostheses implanted into the venous and arterial systems. To evaluate and compare the pathogenesis of pseudo-intimal hyperplasia (PH) of venous and arterial prostheses, a segment of the inferior vena cava (n = 16) or abdominal aorta (n = 16) was substituted by a 3 mm internal diameter polytetrafluoroethylene tube graft (PTFE, 3 cm long, 30 microns in nodal distance) in albino rabbits. At designated time intervals (3-28 days) after the replacement, graft patency was examined and the dry weights of the intraluminal deposits measured as an indicator of the degree of PH. The harvested grafts were then subjected to an ultrastructural analysis by means of light microscopy (LM), and scanning electron and transmission electron microscopy (SEM, TEM). All the grafts remained patent during the entire observation period. The PH judged by the dry weight was significantly more extensive in the venous than in the arterial prostheses. The PH on day 28, observed by light microscopes was apparently most extensive in the mid-portion of venous prostheses but in the arteria prostheses it was mostly seen at the anastomotic sites. The lining of the intraluminal surface of the prostheses with endothelial-like cells observed by SEM was faster and more extensive in venous than in arterial prostheses. The process of PH in venous prostheses observed by TEM may be divided into the following steps: early thrombosis, phagocytosis of the thrombus, appearance of fibroblasts, growth of endothelial-like cells, appearance of smooth muscle cells, and pseudointimal thickening and proliferation of fibroblasts producing collagen fibrils. The process in arterial prostheses was essentially identical to that in venous prostheses but was much slower and less extensive. From these observations, it was concluded that the formation of PH occurs much faster in venous than in arterial prostheses, although the mechanism of PH is mostly identical in venous and arterial prostheses.


The reproducibility of colour-coded duplex scanning in measuring arterial wall dimensions. Intimal hyperplasia continues to be a major problem following vascular surgery but experimental evidence suggests that it can be reduced pharmacologically. For clinical studies an accurate, reproducible and non-invasive image of the intima and lumen is required. We have assessed the value of the Acuson 128 Colour Duplex for such studies. Ten patients had their common femoral arteries scanned at a fixed point by two experienced observers on two separate occasions. External vessel diameter, luminal diameter and internal diameter (i.e. the diameter within the internal elastic lamina) were measured in both longitudinal and cross-sectional views. Cross-sectional area and degree of stenosis were all measured and all parameters expressed as limits of agreement. The mean external diameter of the common femoral arteries was 10.5 +/- 1.6 mm. Measurements in the longitudinal view were highly reproducible with limits of agreement ranging from -0.67 - +0.25 mm (internal diameter) to -1.49 - +1.31 mm (luminal diameter). In order to detect a meaningful change in longitudinal external diameter a real difference of 0.86 mm is required representing a change of less than 10%. Cross-sectional diameter measurements were similarly reproducible (-0.73 - +0.47 mm to -1.97 - +1.79 mm). However, cross-sectional area measurements had a wide variation so that the error in degree of stenosis was -25.4 - +30.2%. Thus, duplex ultrasound reproducibly images the layers of the arterial wall. Prospective studies of intimal hyperplasia are feasible but must be based on longitudinal and cross-sectional diameters rather than cross-sectional areas.


Endothelial cell seeding after carotid endarterectomy in a canine model reduces platelet uptake. Post-endarterectomy platelet deposition may play an important role not only in vessel wall healing, but also in the development of progressive stenosis. Using a canine model, we investigated the effect of endothelial cell seeding on platelet deposition on endarterectomised arteries. Thirteen dogs underwent bilateral carotid intimectomy (5 cm long) and one side was seeded with an average of 2 x 10(6) viable freshly harvested endothelial cells. Blood flow was restored 20 min after seeding. On the contralateral side, a sham-seeding was performed. Deposition of 111indium-labelled autologous platelets was studied with sequential gamma camera images 3-5 h, 1, 2, 3, 4 days and 4 weeks after surgery. Platelet uptake was statistically reduced on the seeded side. Animals were killed at 4 weeks (nine dogs) and 5 weeks (four dogs) after surgery. Seven arteries for each group were found to be occluded. We conclude that endothelial cell seeding on endarterectomised arteries is feasible and reduces platelet uptake. Improvement in the efficiency of seeding and reduction of endothelial cell loss might permit clinical application of this technique.


Storage in sodium chloride does not impair arterial prostacyclin release. Heparinised sodium chloride solution is often used for the storage of veins and to prevent clotting in the arterial tree during vascular surgery. Sodium chloride deranges the morphology of endothelial cells and has therefore been interpreted as "toxic" to the endothelial cell. Perfused human saphenous veins and rabbit aortas show the same pattern of prostanoid release even though veins have a lower release than arteries. Excised rabbit aortas were stored in either (a) 0.9% sodium chloride or (b) 0.9% sodium chloride with heparin 5 I.U. ml-1 prior to being mounted in a perfusion model. The vessels were perfused ex vivo for 5 x 15 min with either Hanks' balanced salt solution (HBSS), calcium- and magnesium-free HBSS or 0.9% sodium chloride. For the last period, arachidonic acid (AA) 4 micrograms ml-1 was added. The release of prostacyclin, measured as the stable degradation product 6-keto-PGF1 alpha by radioimmunoassay, was not altered by storage in sodium chloride, or 0.9% sodium chloride plus heparin when compared with control segments. Perfusion with 0.9% sodium chloride did, however, significantly (p greater than 0.05) decrease the prostacyclin production when AA was added. This is most likely to be due to the low pH of the sodium chloride solution. It is concluded that short-term storage of rabbit aorta in sodium chloride plus heparin or 0.9% sodium chloride does not impair the prostacyclin cascade from the vessel wall, which might be of importance when choosing storage medium for reversed veins and veins used for coronary bypass surgery.


Inflammatory aortic aneurysms: characteristic appearance on magnetic resonance imaging. Ten to 15% of all aortic aneurysms show inflammatory change. They are characteristically covered on their anterior and lateral sides with thick white fibrous tissue. Peri-aortic fibrosis may spread into the retroperitoneum to encase and obstruct adjacent organs making operative treatment more difficult and increasing the operative morbidity and mortality. Fifteen patients with inflammatory aneurysms and 46 patients with simple non-inflammatory aneurysms were studied prospectively. Each patient underwent magnetic resonance imaging (MRI) using a Picker Vista MR2055 scanner operating at 0.5 tesla. Each scan was reviewed by a radiologist (G.G.H.) preoperatively and a diagnosis of inflammatory or non-inflammatory aneurysm made. At operation, the diagnosis of aneurysm type was made on macroscopic features of inflammatory change, and confirmed histologically using previously published criteria. The radiological diagnosis was found to correspond to the surgical and pathological diagnosis in all cases. In cases of inflammatory aortic aneurysm the aneurysm wall appeared laminated on MRI scan, showing three or more bright, high-signal layers. These appearances of inflammatory change are characteristic, and were present in all 15 patients with such aneurysms. There were no false positives among those patients with simple aneurysms, and no false negatives. Operative specimens of aortic wall were taken from four patients with inflammatory aortic aneurysms and four patients with simple non-inflammatory aortic aneurysms, and subjected to MRI scanning. The characteristic banding appeared only in the inflammatory aneurysm wall samples. Magnetic resonance imaging is a highly sensitive investigative technique for the detection of inflammatory aneurysms, showing characteristic changes. These changes are also seen in in vitro scans of wall samples from inflammatory aneurysms.(ABSTRACT TRUNCATED AT 250 WORDS)


Postural changes in femoral artery blood flow in normal subjects, patients with peripheral vascular occlusive disease and patients undergoing lumbar sympathectomy, measured by duplex ultrasound flowmetry. Regulatory peripheral vasoconstriction occurs in response to lower limb dependency. In mildly ischaemic limbs these responses are retained but are lost in patients with rest pain. Previously used methods have inherent difficulties when applied during postural change. We studied orthostatic responses in 12 normal subjects (aged 22-74 years, median 52 years) and 16 patients (aged 21-83 years, median 48 years) with mild and severe peripheral vascular disease using a duplex ultrasound flowmeter. In the normal subjects the 60-s mean common femoral artery volume flow values (ml min-1 +/- S.D.) were 77 +/- 83; -78 +/- 116; -190 +/- 136 for elevation, dependency and standing respectively. For claudicants (n = 7) the values were 18 +/- 37; -112 +/- 123; -216 +/- 103, respectively. In rest pain patients (n = 9) the responses were reversed, being -252 +/- 124; 131 +/- 89 and 184 +/- 85. Significant differences were apparent between elevation, dependency and standing flows, in each of the three groups (all p less than 0.0001). The rest pain group displayed characteristically different responses compared with both normal subjects and claudicants, for each postural change (p less than 0.0001 in all cases). Investigation of the dependency response was undertaken in eight further patients with rest pain before and after lumbar chemical sympathectomy and a characteristic pre-sympathectomy response predicted the clinical outcome.


Treatment of mycotic aneurysm of the aorta and its branches: the location determines the operative technique. Twenty-seven patients with mycotic aneurysms of the aorta and its major branches were operated on between 1969 and 1991. There were 24 males and three females ranging in age from 6 to 84 years (mean age for adults 63 years). Sixteen of the 27 (59%) aneurysms were ruptured and in situ repair was undertaken in 20 (74%) patients. The mean follow-up was 5.8 years (range: 8 months to 16 years). Four patients (15%) died during the hospital stay and 23 survived. There were eight late deaths, two of which were a direct result of the aneurysm. The estimated 1- and 5-year survival rates were 62 and 36%, respectively. Extra-anatomic reconstruction is the method of choice for the majority of patients with mycotic aneurysm of the infrarenal abdominal aorta and iliac arteries. In situ repair after an extensive debridement of the aneurysmal wall and all infected tissue combined with antibiotic therapy is a satisfactory method of treating mycotic aneurysms of other locations, and for a highly selected group of patients with infrarenal mycotic aortic aneurysms.


Popliteal embolectomy: does it still have a role? The failure of a femoral embolectomy presents a difficult problem. The role of popliteal embolectomy in the subsequent management is still not clear. A study of 12 patients who underwent a secondary popliteal embolectomy is reported. Nine of the 12 patients had successful results in terms of limb salvage. The question that has to be addressed is the role of popliteal embolectomy as opposed to thrombolysis. Recent studies tend to favour the latter approach. It is concluded that if an embolectomy catheter will not pass or will not clear the distal segment, the surgeon should consider intraoperative thrombolysis or popliteal embolectomy prior to embarking on a bypass procedure.


Bilateral mycotic axillary artery false aneurysms in an intravenous drug user: unsuspected broken needle-tips pose a risk to the treating personnel. Mycotic false aneurysms due to local arterial injury from attempted intravenous injections in drug addicts are increasing in frequency. The high incidence of HIV and hepatitis B virus in parenteral drug users may present a considerable risk to the treating personnel. This paper reports the unsuspected presence of broken needle-tips in the subcutaneous tissues of an intravenous drug abuser, in association with bilateral mycotic aneurysms of the axillary arteries. Broken needle-tips have the potential to cause needlestick injury to the operating team and the nursing staff, with the associated risk of transmission of HIV and hepatitis B virus infection. The presence of broken needle-tips should be suspected in drug users presenting with false aneurysms associated with local arterial injection injury and a specific history of needle-breakage should be sought. Preoperative plain radiographs should be performed of the planned operative field to exclude the presence of such needle-tips. Any soft tissue swelling in the vicinity of a major artery in an intravenous drug abuser should be suspected of being a false aneurysm until proven otherwise and should prompt immediate referral to a vascular surgeon for investigation and management.


Abdominal aortic aneurysmectomy in a renal transplant patient. Standard surgical techniques were modified to allow continued perfusion of a renal allograft during resection of a large symptomatic abdominal aortic aneurysm. Neither hypothermic perfusion nor temporary bypass were employed. No alteration in renal function was observed and the patient remains well. Complex methods of renal allograft protection are probably unnecessary when transplant recipients undergo aortic reconstruction. However simple modifications or technique can substantially reduce renal ischaemic time and further add to the safety of the procedure.


[Current aspects of the mechanism of action of calcium antagonists in patients with diabetes mellitus]. The review summarizes recent data about the use of calcium channel blockers for the treatment of cardiovascular complications in patients with diabetes mellitus. It is shown that disturbances of Ca ion homeostasis play an important role in the pathogenesis of such diabetic complications as cardiomyopathy, microangiopathy, hypertension and the use of modern calcium channel antagonists for their treatment seems to be quite justified. However, despite definite positive effects of such treatment, these drugs should be used with care, especially if combined with derivatives of sulphonylurea as activators of the beta-cell function. Calcium channel blockers may intervene in the mechanism of the activity of beta-cells in which activation of the calcium channels is an obligatory link for triggering insulin secretion. Nevertheless, according to most of the authors, in such cases Ca antagonists can be recommended in moderate doses under continuous control of the hormonal status of the patient.


[Age-related changes in inotropic effects of noradrenaline and acetylcholine on the myocardium of guinea pigs]. The inotropic effects of noradrenaline (10(-7)-10(-5) M) and acetylcholine (10(-8)-10(-6) M) were studied in experiments carried out on preparations of the right atria and on papillary muscles of the right ventricle in adult (4-5 months) and old (18-24 months) guinea pigs. An age-related decrease in inotropic noradrenaline effects and the displacement of dose-effect relationships to the right was revealed. Similar changes of the dose-related effects of acetylcholine superfused against the background of noradrenaline action were observed. The direct inotropic action of the acetylcholine did not change with ageing. A lack of the essential atrial-ventricular differences in age-related changes in myocardial reactivity is apparently very significant for support of effective functional coupling of cardiac chambers in ageing.


[Resonance oscillations in the human arterial system]. The paper summarizes the results of the experiments aimed at obtaining sphygmograms of peripheral and carotid arteries with due regard to the values of longitudinal dimensions of body and extremities in healthy subjects. Mathematical equations expressing the fact that dicrotic waves recorded on sphygmograms are the reflections of blood eigentones coinciding with resonance oscillations have been derived. It is proved that at least two partial vibration systems oscillating with different own frequencies are present in human arteries. Conditions under which the resonance of constituent frequencies of pulsatile pressure waves and output waves in arteries occurs have been determined. From this point of view a new explanation for the well-known phenomenon of the pulsatile wave amplitude increase from the heart towards peripheric regions is proposed.


[The role of the endothelium in the vascular effects of vintoperol]. The effects of vintoperol have been studied in the experiments on the vascular bed of femoral artery of 15 mongrel dogs under chlorazol-urethane narcosis and on isolated vascular preparations of rats. It is shown that ++de-endothelization of vascular bed using saponin and mechanical removal of endothelial stripes decreased the vasodilatation reaction and relaxation of stripes by 50-60% of the initial values. While infusing ventoperol (0.3 mg.kg-1 min-1) to ++de-endothelized vascular bed, the blood flow increased by 18 +/- 5% as against 47 +/- 3.9% of the initial value under intact endothelium. Blockade of guanylate cyclase by methylene blue decreased blood flow under vintoperol action to 24 +/- 3.5%. The similar results are obtained in the experiments in vitro. After ++de-endothelization of pulmonary artery++ the amplitude of relaxation of preactivated smooth muscles decreased vs. initial tone (21 +/- 3.7% vs. 56% +/- 5.3%). Inhibition of relaxation reaction of vascular stripe under vintoperol effect is also observed after treatment with gossypol, or methylene blue. Thus, endothelium is involved in the realization of vasodilating effect of vintoperol, its action being mediated by endothelium--derived relaxing factor.


[Experimental substantiation of the possibility to obtain anti-Proteus plasma]. The possibility to produce the anti-Proteus plasma is experimentally substantiated. It is determined that polyvalent Proteus antigen immunization permits producing blood immune preparation, that is the high-active anti-Proteus plasma. its antibodies belonging to the class of immunoglobulin G. The anti-Proteus plasma in liquid (at t = 6 degrees divided by 2 degrees C) and in frozen (at t = 20 degrees-5 degrees C) forms retains the specific activity for 3 days and 6 months, respectively.


[Effect of beta receptor blockaders on the status of the lysosomal system of peripheral blood neutrophils in rabbits with immobilization stress]. The investigation carried out on mature rabbits under conditions of beta-adrenoreceptors' blocking by obsidan has revealed that 12-hour immobilization caused neutrophilic leukocytosis in the peripheral blood, degranulation of neutrophils, increase of acid phosphatase activity. These changes occurred much earlier as compared with those in the control group were more pronounced and lasted for a less period of time. Consequently, beta-receptors are the necessary components in the formation of stress-syndrome under the influence of an +non-infectious stressor.