Biomedical subjects

W Debek

Publications and source records attributed to W Debek.

31 records · Page 2Linked to original sources

PubMed1995

Luminol-chemiluminescence in free peritoneal cells in hemorrhagic shock in rats treated with PAF-receptor-antagonist BN 52021.

The activity of rat peritoneal cells were assessed by the phorbol mirystinian acetate (PMA)-induced luminol chemiluminescence (LCL). Results in control groups (0 - no manipulation, and I - carotid artery cannulation) were compared with those in the untreated hemorrhagic shock (group II), in the shock treated with the standard polyelectrolyte solution (PES) (group III), and in shock treated with PAF receptor-antagonist BN 52021 + PES (group IV). The maximal and the most rapid LCL was observed in the group treated with BN 52021 (group IV), while chemiluminescent response in the the untreated shock (group II) and in shock treated with PES was minimally expressed and late. The findings indicate for a rapid activation of peritoneal cells during ca 1 hour of hemorrhagic shock. This leads to exhausting their ability to the superoxide anion generation 15 minutes later. Peritoneal cells obtained from the group treated with the BN 52021 revealed a preserved ability to the respiratory burst. It can be concluded that BN 52021 effectively inhibits activation of the PC during hemorrhagic shock.

Analysis of Variance↗

PubMed1995

Cathepsin D activity in the intestinal wall in experimental untreated hemorrhagic shock.

The total cathepsin D activities in the intestinal wall and in venous mesenteric and arterial systemic blood were investigated on the rats in untreated hemorrhagic shock lasting 60 minutes. We observed a decrease in cathepsin D activity in homogenates of respective segments of small and large bowels and an increase in the enzyme activity in blood serum of both origin. The shock resulted in lowering protein concentration in the intestinal wall and its increase in the mesenteric blood. We found a negative correlation between cathepsin D activity in the intestinal wall and its morphological destruction. Molecules of the enzyme, after liberation from lysosomes due to hemorrhagic shock, are translocated to the circulation and probably to the gut lumen. Liberation of the intestinal cathepsin D may contribute to the local damage and multiorgan failure in hemorrhagic shock.

Amino Acids↗

PubMed1995

Activity of exoglycosidases of the rat abdominal organs in untreated hemorrhagic shock.

Exoglycosidases catabolize glycoconjugates (proteoglycans, glycolipids and glycoproteins) at a rate depending on tissue and pathological changes. We determined exoglycosidase activity in successive sections of alimentary tract, spleen, liver and kidney of rats subjected to hemorrhagic shock. We found significant difference in exoglycosidase activity between alimentary tract segments in control animals and no significant changes in homologous tissues of the shocked rats comparing with control.

Animals↗

PubMed1995

Mast cells in the gastrointestinal tract.

The morphology and functions of gastrointestinal mast cells (MCs) under physiological and pathological conditions were described. Special attention was paid to the MCs origin, differentiation and morphological and biochemical aspects of their degranulation. Mast cells are important component of normal architecture of the gastrointestinal tract. Many substances released from MCs during degranulation are biologically active and mediate numerous processes: blood flow regulation, epithelial and endothelial permeability, mucosal secretion, gastrointestinal tract motility, immunological events related to the antigens of various origin, angiogenesis, cancer development. Thus MC is often considered as an important agent in pathogenesis of many gastrointestinal diseases. The gastrointestinal diseases which was described in this paper are following: bacterial and parasitic infections, peptic ulcer, ulcerative colitis, Leśniowski-Crohn's disease, inflammatory polyps, intestinal graft-versus-host reaction, neoplastic tumors, mastocytosis, intestinal ischemia.

Adrenergic Fibers↗

PubMed1995

Ginkgolide BN 52021 protects against hemorrhagic shock-induced renal injury in rats.

Degree of renal damage in experimental untreated and treated hemorrhagic shock was estimated in light microscopy. Histological preparations were scored with a semiquantitative scale concerning the changes which are typical for the acute renal failure. It was found that an early treatment with the PAF-receptor antagonist (ginkgolide BN 52021) considerably reduced morphological changes observed in rat kidney in hemorrhagic shock, comparing with untreated shock and in shock treated with a polyelectrolyte solution.

Acute Kidney Injury↗

PubMed1995

Oxygen-derived free radicals in kidney in experimental hemorrhagic shock treated by PAF-receptor antagonist BN 52021.

Renal damage in rat hemorrhagic shock model was assessed by estimation of the reactive oxygen metabolites generation (malondialdehyde measured as thiobarbituric acid reactive substances) and antioxidative potential (activity of Cu-, Zn- superoxide dismutase, activity of glutathione reductase and level of sulfhydryl compounds). It was found that treatment with BN 52021 (a platelet-activating factor antagonist), and polyelektrolyte solution had had a beneficial effect in comparison with both the untreated shock and shock treated by reperfusion only.

Analysis of Variance↗

PubMed1995

Megakaryocytes in the acute stage of experimental hemorrhagic shock. Part I. Megakaryocytes circulating in the blood.

Megakaryocytes were evaluated in the blood of the caval vein of rats in the acute stage of hemorrhagic shock. The number and morphological types of MK were analysed. Millipore filters were used for the evaluation. MK were found to be a physiological element of the blood. An increase in the MK number leaving the bone marrow in rats with the acute stage of hemorrhagic shock was observed. A rise in the total MK number was accompanied by an increase in the percentage of mature and "naked nucleus" MK.

Acute Disease↗

PubMed1995

Megakaryocytes in the acute stage of experimental hemorrhagic shock. Part II. Megakaryocytic regulation of cell release from the bone marrow.

The contribution of MK to the release of other marrow cells to the blood was evaluated in rats subjected to experimental hemorrhagic shock. The analysis was based on the frequency of emperipolesis phenomenon in megakaryocytes, which was evaluated in a light microscope on marrow smears and in ultrastructural examinations. A considerable increase was found in the number of marrow cells in the MK cytoplasm in the animals examined, which indicates a significant part of MK in the release of these cells to the blood and in the marrow-blood barrier formation by MK.

Acute Disease↗

PubMed1995

Megakaryocytes in the acute stage of experimental hemorrhagic shock. Part III. Histomorphometrical evaluation of megakaryocytes.

The authors presented the morphometrical evaluation of the bone marrow MK in rats in the acute stage of experimental hemorrhagic shock. The experiments used a semiautomatic computer programme. The total number of MK per 1 mm2 of the bone marrow was analysed with regard to various morphological forms of MK, their surface area, shape disorders, nuclear-cytoplasmic ratio and cluster forms. A considerable shift was observed in the MK parameters examined, suggesting a significant effect of hemorrhagic shock upon megakaryocytopoiesis.

Acute Disease↗

PubMed1994

Influence of brain hypoxia on megakaryocytic emperipolesis in rats.

An evaluation of frequency and intensity of the megakaryocytic emperipolesis in the rat bone marrow after unilateral carotid artery occlusion was performed. The results were compared with those obtained in the group undergoing a blood loss and the group not subjected to surgical procedures. A significant increase in the frequency of emperipolesis was found in the bled rats following a carotid artery cannulation, but also in animals exposed to the carotid artery occlusion only. In most cases the cytoplasm of megakaryocytes contained granulocytes and erythroblasts. The observed emperipolesis phenomenon is likely to be a result of brain hypoxia and a secondary neurogenic stimulation of the bone marrow activity.

Animals↗

PubMed1994

[Phenomenon of emperipolesis of bone marrow megakaryocytes in experimental hemorrhage shock in rats].

An evaluation of frequency and intensity degree of emperipolesis in megakaryocytes of the bone marrow in rats subjected to the hemorrhagic shock was performed. The results were compared with those obtained in the groups of animals undergoing a sham operation and not subjected to any surgical procedure at all. A statistically significant increase was found in the frequency of emperipolesis in the shocked rats compared with the remaining groups. The cytoplasm of megakaryocytes most frequently revealed the occurrence of granulocytes and erythroblasts. However, differences in the frequency of respective hematopoietic cells were not significant.

Animals↗

PubMed1993

[Study of platelet count and phagocytic activity in experimental hemorrhagic shock. II. Evaluation of phagocytic activity of platelets].

The platelets phagocytic activity has been measured in rats during experimental haemorrhagic shock determining the per cent of phagocytic platelets and phagocytic index. The authors have the decrease of phagocytic activity of platelets during haemorrhagic shock. Disturbances of phagocytic activity of platelets have been accompanied by changes of their shape and formation platelet aggregates.

Animals↗

PubMed1989

[Pulmonary megakaryocytes (MK) in experimental hemorrhagic shock].

Quantification of MK in blood and pulmonary sections was performed in rabbits with induced hemorrhagic shock (group I) and in control rabbits (group II). In electron transmission microscopy we studied the ultrastructure of pulmonary capillaries. Animals in group I were exsanguinated to achieve systemic blood pressure level of 40 mm Hg. This level was maintained for 1.5 hours and then the rabbits from both groups were sacrificed. Pulmonary arterial and venous blood was sampled in the amount of 10 ml and two sections from each pulmonary lobe were taken. The blood samples were then treated with Streptolysine 0 in order to isolate MK which were counted in the smears. In pulmonary sections MKs were counted per 1 cm2. In animals with shock we found an increase in MKs in the pulmonary artery (means = 4.9 MK/ml against means = 1 MK/ml in venous blood; corresponding values for group II were means = 1.7 MK/ml and 1 MK ml respectively). In the lungs of rabbits in group I we found considerable accumulation of MKs means = 22.4 MK/cm2 (corresponding value for group II means = 2 MK/cm2). It was found that hemorrhagic shock was probably the factor activating the release of MK from the bone marrow to the periferal blood, whereas pulmonary capillaries were an effective filter uptaking circulating MKs. Edematous changes in the capillary endothelium were probably the factors intensifying the process of pulmonary uptake of MK. We discussed the value of pulmonary accumulation of MK in the development of mechanisms leading to adult respiratory distress syndrome.

Animals↗