Fifty-day-old fry of tilapia hybrids (Oreochromis aureus x niloticus) were placed in aquaria containing sediment with oocysts of Eimeria (sensu lato) vanasi Landsberg et Paperna. In the first 29 h after exposure sporulated oocysts in the stomach and free sporozoites in the gut could be found in examined fish. By 7 to 56 h after exposure, sporozoites, with their characteristic crystalloid body, were detected in intraepithélial lymphocyte-like and other leucocyte-like cells, but never in the epithelial cells. Infected cells were confined to the epithelial layer and did not enter the lamina propria. Within this time, some of the sporo-zoitcs divided by endodyogeny, once or twice in succession, to form daughter sporozoites. The parent’s sporozoite crystalline body was divided between the offspring of the primary and secondary divisions.
Atherogenesis involves the migration of leukocytes into vascular subendothelial space, a process mediated by endothelial and leukocyte cell adhesion molecules. Endothelial molecules are assessed indirectly via serum levels, but leukocyte molecules can be assessed directly. We have therefore hypothesized that leukocyte adhesion molecules are altered to a greater degree in hypercholesterolemia than serum endothelial adhesion molecules. We examined 29 subjects with hypercholesterolemia and 27 controls at baseline and after 12 weeks of atorvastatin treatment (20 mg/day). Expression of leukocyte integrins CD11a, CD11b, CD18, and CD49d and of L-selectin was measured by flow cytometry. Serum ICAM-1, E-selectin and von Willebrand factor were measured by ELISA. Expression of leukocyte adhesion molecules was significantly higher in patients at baseline than in the controls, except for CD11a. Expression significantly decreased after atorvastatin in most adhesion molecules except for CD11b. In contrast, there was no effect of hypercholesterolemia and/or atorvastatin on the serum endothelial molecules. Leukocyte but not endothelial adhesion molecules were influenced by hypercholesterolemia and by lipid lowering treatment. Leukocyte molecules may therefore be a more sensitive marker of atherogenesis than endothelial molecules. Our results support the role of increased leukocyte adhesiveness in atherogenesis., T. Štulc, M. Vrablík, Z. Kasalová, I. Marinov, H. Svobodová, R. Češka., and Obsahuje bibliografii a bibliografické odkazy
The quality of stored blood can be deteriorated by hemolysis caused by free radicals. The purpose of this study was to elucidate whether neutrophile leukocytes are the source of free radicals in stored blood as in hemodialyzed patients. Resuspensions with low (LL) or high (HL) leukocyte concentrations were prepared from samples of twenty healthy volunteers. The samples were incubated for 10 days at 4 °C and then for one day at 37 °C. Markers of hemolysis and free radical metabolism were examined before and after incubation in LL and HL samples. In spite of the difference of leukocytes counts in LL and HL resuspensions (p<0.0001), the pre-incubation values of all laboratory parameters were practically identical. In post-storage samples, superoxide dismutase and glutathione peroxidase activities did not differ in either group. Reduced glutathione in erythrocytes and extracellular antioxidant capacity were insignificantly lower in HL resuspensions, but the increase of malondialdehyde was much more pronounced in the HL samples (p<0.0001). The degree of hemolysis, expressed as the extracellular increase of potassium (p<0.001), hemoglobin (p<0.05) and lactate dehydrogenase (p<0.05), was higher in the HL samples. Our results support the hypothesis that leukocytes participate in free radical production in stored blood., J. Racek, R. Herynková, V. Holeček, J. Faltysová, I. Krejčová., and Obsahuje bibliografii