Effect of NO inhibitors on hypovolemic shock-induced hypotension.

In vivo effect of isothiourea derivatives on NO production was studied by the method of electron paramagnetic resonance spectroscopy with a spin trap. We evaluated the influence of these compounds on hemodynamic parameters in anesthetized rats with hypovolemic shock. A correlation was found between the size of S,N-substituents in isothiourea derivatives (methyl, ethyl, and isopropyl) and NO inhibitory activity of compounds.

Role of cyclooxygenases in the stimulatory effect of carcinogen 1,2-dimethylhydrazine on stem cell survival in the intestinal epithelium and bone marrow.

In vivo experimental studies showed that 1,2-dimethylhydrazine and product of its metabolism in the body azoximethane improve postradiation survival of two types of stem cells in the adult organism: hemopoietic stem cells and intestinal epithelial stem cells. This effect similar to the well-known radioprotective effect of E. coli lipopolysaccharide was observed, when the carcinogen was administered 1 day before gamma-irradiation.

Effect of factor VIII on tissue factor-initiated spatial clot growth.

Using time-lapse videomicroscopy, we studied the role of coagulation factor VIII (fVIII) in tissue factor-initiated spatial clot growth on fibroblast monolayers in a thin layer of non-stirred recalcified plasma from healthy donors or patients with severe Haemophilia A. Analysis of temporal evolution of light-scattering profiles from a growing clot revealed existence of two phases in the clot growth-initiation phase in a narrow (0.2 mm) zone adjacent to activator surface and elongation phase in plasma volume.

Hemophilia A and B are associated with abnormal spatial dynamics of clot growth.

To gain greater insight into the nature of the bleeding tendency in hemophilia, we compared the spatial dynamics of clotting in platelet-free plasma from healthy donors and from patients with severe hemophilia A or B (factor VIII:C or IX:C<1%). Clotting was initiated via the intrinsic or extrinsic pathway in a thin layer of nonstirred plasma by bringing it in contact with the glass or fibroblast monolayer surface. The results suggest that clot growth is a process consisting of two distinct phases, initiation and elongation.

Antibodies to morphine as indicators of chronic morphine intoxication and impaired immune reactivity.

Chronic morphine treatment of rats for 2 and 4 weeks led to an increase in morphine-binding cells in the spleen, despite the general reduction of mononuclear cell content in the spleen and thymus. Simultaneously, serum antibodies to morphine (AbM) in haemagglutination titres 1:20 and higher appeared in 50% and 80% of animals, respectively. Animals with high titres of AbM had much weaker immune response to a thymus-dependent antigen (sheep red blood cells).