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Biomedical subjects

M Urban

Publications and source records attributed to M Urban.

At least 109 records · Page 6Linked to original sources
PubMed1996

Dupuytren's disease in children.

Although Dupuytren's disease of the hand has been reported in teenagers, it is generally considered to be a disease of adults. A series of nine children who developed Dupuytren's disease of the hand before the age of 13 years is presented. Eight had surgical removal of the diseased tissue and histological confirmation of the diagnosis before the age of 13 years and one at 14 years of age. The presence of the condition in young children and teenagers is discussed and the literature summarized.

Adolescent↗
PubMed1996

Glycoprotein H of human cytomegalovirus is a major antigen for the neutralizing humoral immune response.

A recombinant baculovirus expressing glycoprotein H (gpUL75) of human cytomegalovirus was used to examine the humoral immune response in naturally infected individuals. Recombinant baculovirus infected insect cells produced two forms of gH with molecular masses of 78-82 kDa and 94 kDa. The 94 kDa polypeptide was modified by high mannose oligosaccharide side-chains as shown by reduction in molecular mass after treatment with endoglycosidases H and F. The 78-82 kDa protein represented the non-glycosylated precursor which was resistant to the enzymes. In contrast to gH expressed in mammalian cells, the recombinant baculovirus expressed gH was transported to the cell surface. Glycoprotein H produced in insect cells was reactive with human convalescent sera and all tested neutralizing monoclonal antibodies recognizing either linear or conformational epitopes. Antibodies reacting with insect cell derived gH were detected in 96 percent of HCMV seropositive human sera. Using insect cells infected with the gH expressing recombinant baculovirus as immunoabsorbent, between 0 percent and 58 percent of the total virus neutralizing activity was removed from sera of individuals with a past HCMV infection. gH must therefore be considered a major antigen for the induction of neutralizing antibodies during natural infection.

Animals↗
PubMed1996

Rab3 proteins and SNAP-25, essential components of the exocytosis machinery in conventional synapses, are absent from ribbon synapses of the mouse retina.

GTP-binding rab proteins, present in synaptic vesicles and endocrine secretory granules, have been shown to be involved in the control of regulated exocytosis. We found rab3 proteins in immunoblots of diverse areas of the mouse central nervous system (spinal cord, olfactory bulb, hippocampus, cerebellum and neocortex). Immunohistochemical observations at light- and electron-microscopical levels in the hippocampus and other areas revealed rab3 proteins in virtually all synaptic fields and terminals of the areas investigated. In the retina, rab3A immunoreactivity was confined to the inner and outer plexiform layers. Ultrastructural examination revealed that rab3A was present in conventional terminals in the inner plexiform layer and in horizontal cell processes of the outer plexiform layer. In contrast ribbon synapses, which play a key role in transferring information from the photoreceptor cells to the central nervous system, were immunonegative. We also tested whether other proteins of the rab3 family are present in ribbon synapses. However, using an antibody recognizing rab3B and rab3C in addition to rab3A, we found no immunoreactivity in these synapses. Interestingly, we observed also no immunoreactivity for synaptosomal-associated protein 25 (SNAP-25) in ribbon synapses, but conventional synapses and horizontal cell processes were heavily stained. Our data show that the known rab3 and SNAP-25 isoforms, which are components of the secretory apparatus of conventional synapses, are absent from ribbon synapses of the retina. Our observations suggest different mechanisms of transmitter exocytosis in conventional and ribbon terminals.

Animals↗
PubMed1996

[Circadian rhythm of blood pressure in adolescents with hypertension and insulin dependent diabetes mellitus].

Assessment of blood pressure values and their circadian rhythm were performed a group of adolescents with borderline hypertension and in patients with insulin dependent diabetes mellitus. Higher values of blood pressure in children with IDDM in comparison with healthy children and slighter decrease of nocturnal blood pressure in the investigated groups of adolescents were shown.

Adolescent↗
PubMed1996

[Nitrite formation and nitrosation potential of heterotrophic biological denitrification of drinking water in laboratory conditions].

In a laboratory construction for heterotrophic biological denitrification of drinking water treatment, the formation of nitrite, the potency of nitrosation and the genotoxic activity were tested. Parameter as nitrate concentration, the water flow rate in the system, nitrite and morpholine addition and the pH-value were checked. For testing the potency of nitrosation and formation of nitrite in the reactor we took morpholine, a fast nitrosing amine. The results show for the break down rate of nitrate, there is no influence of the initial nitrate concentration (80-195 mg/L), the nitrite addition (5-20 mg/L) and the water flow rate (45-100 min) in the system. pH-values below 5.5 showed a little break down rate of nitrate. There was no correlation between the starting point of nitrate concentration and the formation of nitrite, although there was a positive correlation between the length of stay and the formation of nitrite. Nitrite concentrations of 5 mg/L with morpholine concentrations of 5 and 10 mg/L didn't show detectable formation of nitrosomorpholine. The analyses of different watertests in the construction didn't show significant results for DNA damage by the sister-chromatid exchange (SCE). The results of the Salmonella microsome assay (tester strain TA1535) didn't show any mutagenic effects relating to the potency of nitrosation. According to our experiments the potency of generalising nitrosamides or nitrosamines by drinking water denitrification seems to be low. There is no final assessment of detriment to health by denitrifying drinking water.

Animals↗
PubMed1995

Purification of cell populations from human fetal brain using flow cytometric techniques.

We recently established primary cultures from dissociated second trimester human fetal brains using a novel spin seeding method and characterized cellular populations with distinct phenotypes in these cultures. Here, we report that these neural cultures can be dissociated to single-cell suspensions, sorted by size using flow cytometry and re-seeded to yield cultures selectively enriched for the neuronal and glial cell populations. Sorted neurons were highly homogeneous, viable and extended processes, by one day after re-seeding. These neurons expressed immunoreactivity for neurofilament protein, retained their GABAergic phenotype and were electrically excitable. Re-seeded astrocytes proliferated in culture and expressed glial fibrillary acidic protein. We describe the conditions required for the flow cytometric sorting and tissue culture assays as well as the morphological, immunocytochemical and electrophysiological characteristics of the sorted neuronal population.

Brain↗
PubMed1995

Conventional film-screen versus computed storage phosphor radiography. Simulated miliary lung disease in an anthropomorphic phantom.

RATIONALE AND OBJECTIVES: In this experimental study, the authors examined whether laser printed hardcopies from digital storage phosphor radiographs yield diagnostic performance equal to conventional film-screen radiographs in the detection of simulated miliary disease, using a standardized object. METHODS: A commercially available anthropomorphic chest phantom was used for radiographic evaluation. Miliary disease was simulated by superimposing one to four sheets of millet seeds on the lungs, resembling a miliary disease pattern with varying degrees of detectability. An observer study (receiver-operating characteristic) with eight radiologists was conducted to compare the reader performance using hardcopies of computed storage phosphor radiography versus the conventional film-screen system, optimized for chest x-rays. The digitally generated images were presented as a double-image hardcopy, with a conventionally adopted version and an edge enhanced image version. RESULTS: When analyzed separately, one out of the eight observers performed slightly better using the conventional films. When treated as a group, analysis of the areas under the receiver-operating characteristic curves demonstrated no significant difference in reader performance for each of the systems under investigation (t = 0.286). The Wilcoxon test could not prove a statistical difference. CONCLUSION: Storage phosphor technology is a method that yields equal diagnostic performance as conventional film in evaluating miliary disease of the chest.

Adult↗
PubMed1995

Anaesthetic management of bone marrow transplant recipients less than two years of age.

The charts and anaesthetic records of 97 infants less than two years of age who underwent bone marrow transplantation at the University of Minnesota from 1978-1992 were retrospectively reviewed. These infants underwent 564 general anaesthetics. There were 48 perioperative complications, most (39) involving the airway. There were 20 difficult intubations occurring in 13 patients. The causes of the difficult intubations were anatomical abnormalities (12), mucositis (4), pharyngeal oedema (3) and emesis upon induction of anaesthesia (1). Four intraoperative deaths occurred. The deaths were caused by haemorrhage (2), pulmonary embolism (1) and myocardial ischaemia (1). Four patients died within 72 h of surgery; one from cerebral oedema following an intraoperative cardiac arrest, one from fungal septicaemia, one from haemorrhage and one from multiple organ failure following an intracerebral haematoma. Infants undergoing bone marrow transplantation are at high risk for perioperative morbidity and mortality, particularly from complications involving the airway, bleeding or sepsis.

Anesthesia, General↗
PubMed1995

[Oxidants and antioxidants. Biological effects and therapeutic perspectives].

The main oxidizing free radicals (FR) are oxygen-derived metabolites (superoxide anion O2-, hydrogen peroxide H2O2, hydroxyl radical OH (zero)), hypochloric acid, chloramines, nitrogen dioxide, ozone and lipid peroxides. They are produced continually by living organisms, either in the intracellular compartment by the mitochondrial respiratory chain and mixed function oxidase system, or in the extracellular compartment, especially by phagocytes. The body possesses complex protective antioxidant systems against this potentially toxic production, such as dismutase superoxides, catalase, the glutathione enzyme system, metallic ion sequestration, enzymes degrading proteins injured by FR, metabolising hydroperoxides, and repairing DNA, and vitamins E, C, P, and betacarotene. A physiological steady-state is established under normal conditions between the production of oxidants and their neutralization by antioxidants. Oxidative lesions result from a disturbance of the oxidant-antioxidant balance. Oxygen-derived metabolites act on polyunsaturated cell membrane lipids, induce genetic alterations, and oxidize sulfhydryl groups of proteins, thereby modifying their functions. FR are involved in major physiological mechanisms such as phagocytosis, the inflammatory reaction, and the reperfusion ischaemia phenomenon observed during organ storage. The therapeutic use of enzymatic (SOD, catalase, GSH) and nonenzymatic antioxidants (vitamins E, N-acetylcysteine, allopurinol and oxypurinol) has yet to be evaluated. The current state of our knowledge indicates the extreme complexity of these systems and calls for caution in the therapeutic use of antioxidant substances.

Antidotes↗
PubMed1995

[Treatment results of acute lymphoblastic leukemia in children from centers in Białostock and Szczecin].

The retrospective analysis was undertaken in order to assess treatment results of childhood ALL achieved in two "independent" units: in Białystok and Szczecin. It comprised 61 patients: 24 girls and 37 boys aged 10 - 197 months (median 64, mean 73 months), who between November 1987 and December 1992 were diagnosed as having ALL. 25 children, with risk factor greater than 0.8 were classified as intermediate risk patients. ALL 61 children were treated greater than 0.8 were classified as intermediate risk patients. ALL 61 children were treated according to BMF 86 protocol modification of the Polish Leukemia Study Group. The observation was closed in February 1993; the follow-up time was within the range of 10 - 72 months (median 32, mean 32 months). 7 patients (11.5%) did not enter remission, 4 children (6.6%) died in remission and 11 children (18.0%) relapsed. The probability of event-free survival (EFS) and disease-free survival (DFS) were 0.53 and 0.67 respectively. There was no statistical difference in p-EFS between standard and intermediate risk patients (SRG = 0.60 vs IRG = 0.53). It has been shown that p-EFS was not statistically influenced by age, sex, WBC, Hb level, paS-positive and acid-positive ALL. It has been suggested that protocol deviations were the main cause of the inferior (as compared to other domestic centers) treatment results.

Adolescent↗
PubMed1995

[Immunomodulation in Pseudomonas urinary infection].

The urological department is as a rule of department with the highest incidence of nosocomial infections. They are often caused by Pseudomonas aeruginosa. In 1992 the authors started to use prophylactic immunization with antipseudomonas vaccine PSAEVA in 58 patients indicated for surgery on account of an prostate adenoma. During and after operation the incidence of Pseudomonas infection in immunized and control patients was compared. In the immunized group the incidence after operation was 1.72%, in the control group 12%. The drop of Pseudomonas infections in operated patients immunized with the anti-pseudomonas vaccine as compared with non-immunized ones was by 10.28% lower which is statistically significant--p.0.05.

Bacterial Vaccines↗
PubMed1995

[Clinical and immunologic course of systemic lupus erythematosus in a 12-year-old girl].

The report presents the clinical course of a systemic lupus erythematosus in a 12-year-old girl, when the thrombocytopenia was the only symptom over the period of several months. In the subsequent stage of the clinical observation, in the coexistence of the subacute cutaneous lupus erythematosus with visceral changes were noted. The report emphasises the correlation between the clinical symptoms and the immunological disorders as well as the necessity of the complete immunological diagnostics in cases of isolate symptoms suggesting lupus erythematosus.

Child↗
PubMed1994

Pancreatitis associated with remote traumatic brain injury in children.

Vomiting, abdominal distension, and feeding intolerance are common findings following brain injury in children, and are usually attributed to the brain injury or to delayed gastric emptying: a specific cause is usually not sought. We report six children who developed mild to moderate pancreatitis at least 7 days following apparently isolated brain injury, a previously unreported association. Five of the six patients received drugs that are known or suspected pancreatotoxins; all recovered without changes in the medications. When children develop feeding intolerance or upper gastrointestinal symptoms following traumatic brain injury pancreatitis should be suspected.

Acute Disease↗
PubMed1994

Control of mating and development in Ustilago maydis.

In Ustilago maydis the a and b mating type loci control pathogenicity as well as sexual development. We review the function of these loci in controlling the cell fusion step, the switch from yeast-like to filamentous growth and subsequent pathogenic development. Our special emphasis will be the role of pheromones and pheromone signaling in these processes.

Alleles↗
PubMed1994

[Findings of digital intensive or bed lung radiographs at the monitor vs. hard copy: a clinical ROC study].

45 bedside chest examinations acquired with storage phosphorus radiography, were displayed on a viewing box as single-format hard copies and at a high-performance digital reporting console. 6 observers performed an ROC study. For the pathologies under question, significantly better results were shown in monitor reporting due to pneumonic infiltration whereas no significant differences were found for pulmonary or mediastinal masses, or for pneumothoraces.

Adult↗