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Biomedical subjects

K Vass

Publications and source records attributed to K Vass.

70 records · Page 4Linked to original sources
PubMed1984

Ultracytochemical distribution of myelin basic protein after injection into the cerebrospinal fluid. Evidence for transport through the blood-brain barrier and binding to the luminal surface of cerebral veins.

Distribution of myelin basic protein (MBP) in the central nervous system (CNS) following injection into the cerebrospinal fluid (CSF) was studied by different qualitative and quantitative immunelectron -microscopic techniques. Endogenous MBP was present in myelin sheaths in injected as well as in control animals. After injection of exogenous MBP into CSF this protein was present in the subarachnoid space, on the surface of meningeal cells, on the surface of collagen fibers, in the basement membrane of the glia limitans, in vessel walls, and in the extracellular space of spinal roots. In meningeal veins, endothelial vesicles filled with peroxidase reaction product were found on the abluminal side of endothelial cells, in the endothelial cytoplasm and sometimes opening into the vascularllumen . In addition patchy staining of the luminal surface of endothelial cells was noted, indicating binding of antigen at this location. Quantitative immunelectron microscopy (an indirect technique with rabbit anti-MBP serum as primary layer and gold-labeled anti-rabbit IgG as secondary layer) revealed highly significant MBP binding on the luminal surface of endothelial cells after injection of this antigen into the CSF. The present results indicate that MBP, when liberated in CNS is transported through the blood-brain barrier and presented on the luminal surface of endothelial cells of the cerebral and meningeal veins. This observation may be important in interpretation of pathogenesis of initial inflammatory infiltrates in experimental allergic encephalitis (EAE).

Animals↗
PubMed1982

[Drug therapy of sleep disorders in shift workers].

The hypnotic action of a soporific may be of limited use in populations who live in contradiction to their "internal biological clock". In order to test the assumption 60 nurses who had a disturbance in their sleep-waking rhythm due to shift work participated in an one-week double blind study. Nurses were randomly assigned to receive either lormetazepam 1 mg (Noctamid) or placebo (n = 30 per group). In the nurses with disturbance of falling asleep, a normalization of the duration of falling asleep occurred in 15 of 17 cases under lormetazepam as compared to ten of 17 under placebo. In the nurses who slept too little the length of the sleeping time normalized in 15 of 16 cases under lormetazepam as compared to the nine of 16 under placebo. With simultaneous consideration of the duration of falling asleep, total duration of sleep and depth of sleep, a distinction was made between "normalization in all three parameters", "normalization in one or two parameters, but no deterioration in any parameter" and "no normalization" for evaluation of the therapy comparison. The action of lormetazepam was shown in higher improvement rates (p less than 0,05). Neurophysiological and social medical implications are being discussed.

Adolescent↗
PubMed1981

Cloning of a new mouse foetal beta-globin mRNA sequence.

A novel globin cDNA recombinant (pFG5) has been isolated from a 14-15 day Porton mouse foetal liver cDNA library. It codes for a beta-like globin mRNA expressed in foetal liver-derived erythroblasts and erythrocytes but not in adult reticulocytes nor in yolk sac derived nucleated erythrocytes. It is also found in Friend cells induced to differentiate by DMSO. The nucleotide sequence of pFG5 confirms that it does not code for the beta major or beta minor globin chains nor the embryonic epsilon Y2 globin chain; but it is identical to the published partial sequence of the epsilon Y3 globin gene over the region of overlap (78 nucleotides).

Animals↗
PubMed1981

Cerebellar glioblastoma presenting clinically as Wallenberg's syndrome.

The clinico-neuropathological report is given of a glioblastoma multiforme with primary site in the cerebellum. The patient presented clinically with Wallenberg's syndrome; morphological investigations revealed the tumor partly invading the dorsolateral region of medulla oblongata. There are some reports of Wallenberg's syndrome not caused by vascular stenosis or occlusion, but by metastatic tumors in the lateral medullary region. The present report is the first of a cerebellar glioblastoma causing the peculiar brainstem syndrome.

Cerebellar Neoplasms↗
PubMed1978

Ontogeny of human neutrophil granulocyte alkaline phosphatase.

Human embryonic neutrophils (N) in the liver (from 8.5 mm crown-rump length) are alkaline phosphatase (AP) negative during the first trimester of pregnancy. Early bone marrow granulocytes (from eleventh to sixteenth weeks of gestation) behave similarly. Only a small percentage of slightly AP positive cells could be found. Occasional cells with strong NAP reaction appear in the second trimester. NAP positivity greatly increases in the third trimester and term-babies have a somewhat higher than normal NAP activity in circulating blood. Unlike NAP reaction, naphthol-AS-D-chloroacetate esterase and peroxidase reactions are positive even in the earliest (AP negative) neutrophils.

Alkaline Phosphatase↗
PubMedDate not supplied

Role of circulatory disturbances in the development of post-ischemic brain edema.

Two post-ischemic circulatory disturbances that play a significant role in pathophysiology of an ischemic lesion are: (1) reactive hyperemia or hyperperfusion and (2) hypoperfusion. The reactive hyperemia promptly follows release of major cerebral artery occlusion, and it is associated with the opening of the blood-brain barrier to serum proteins and ensuing edema. Prevention or reduction of reactive hyperemia results in significant amelioration of edema and the resulting ischemic brain tissue injury. The post-ischemic hypoperfusion, studied in gerbils, develops soon after recirculation and usually lasts up to 6 h. Its relationship to post-ischemic edema is evident in repeated ischemic insults. In these studies, three ischemic insults of 5 min duration when applied at 1 h intervals, i.e., during the period of hypoperfusion, resulted in a cumulative effect, post-ischemic edema and tissue injury becoming considerably more pronounced that those following a single 15 min ischemia. There was no cumulative effect when the ischemic insults were spaced 3 min or longer than 6 h apart. These observations indicate that repeated ischemic insults taking place during the phase of post-ischemic hypoperfusion may significantly increase the development of edema and brain tissue injury.

Animals↗
PubMedDate not supplied

Prevalence of multiple sclerosis in Austria. Results of a nationwide survey.

The epidemiology of multiple sclerosis (MS) in Austria is almost unknown. We evaluated the prevalence of MS in Austria using data from questionnaires completed by neurologists, comprising information on a total of 1,006 MS patients who attended 30 out-patient specialized clinics nationwide. Additional data were collected from 2,414 MS patients, who received questionnaires from the Austrian MS Society or their doctor. A novel extrapolation model, based on frequencies of patients visits at MS clinics, was used to estimate the overall prevalence of MS. Considering either disability or the course of the disease, the prevalence of MS patients in Austria was estimated to be 98.5 per 100,000 people. The prevalence of MS in Austria was found to be similar to that of other countries in Central Europe. Epidemiological studies, such as this, provide a unique source of data from which key features of a disease and its impact on patients may be examined.

Adult↗
PubMedDate not supplied

Characteristics of smokers who attempt to quit and of those who recently succeeded.

Although a high percentage of smokers attempt to quit each year, success rates are low. Thus, public health strategies must not only convince some smokers to attempt cessation, but also improve the success rate among other smokers already motivated to quit. Specific cessation strategies may be required for smokers in these two groups. This study compares sociodemographic and health behavior characteristics of smokers who have and have not attempted to quit and of those who recently succeeded. To determine whether these characteristics vary for men and women, we stratified analyses on gender. Data were obtained from random sample health surveys conducted 1981-1982 and 1983-1984 in two New England communities. Analyses include data on 2,086 respondents who reported smoking cigarettes in the previous year. Men and women were equally likely both to attempt cessation and to quit. Except for an inverse association with age, attempting to quit was not associated with sociodemographic variables. In men and women, attempts were associated with encouraging others to quit and attempting to increase exercise. Successful cessation attempts were associated with not living with a smoker in women; marital status, attempted weight loss, and increased age in men; and with efforts to increase exercise in both men and women. These characteristics could be useful in targeting smokers who attempt to quit, but fail. Improving the success rate in this group could greatly reduce smoking prevalence in the community.

Adult↗