Effects of liposome form of triombrast on the state of blood and organ lipids in experimental animals

The authors studies the effect of liposomes carrying triombrast on blood and organ lipids contents in rats. Free triombrast doesn't influence the blood and organ lipids content; only in plasma it induced an increase in triglycerides content.     

Role of estrogens in phenobarbital induction of microsomal enzymes of the liver]

The action of estradiol dipropionate (250 microgram/kg) and of phenobarbitone-sodium salt (80 microgram/kg) was studied in separate and combined (a single injection of estradiol-dipropionate after a 4-day administration of the phenobarbital-sodium salt) administration. There was an increase in the H3-phenylalanine incorporation into the cell-free protein-synthesizing system by 86% in comparison with control ovariectomized group. Under these conditions estradiol-dipropionate increased the incorporation of the labeled amino acid by 53%. A combined administration of the estrogen and of the barbiturate was not accompanied by the summation of the given effect. There was revealed a correlation between the increase in the rate of the H3-phenylalanine incorporation in vitro and an increase in the content of the cytochrome P-450 in vivo in the microsomes of hepatocytes in separate and combined administration of the preparations. The role of phenobarbitone-sodium salt as an activator of estradiol metabolism in the hepatocytes is discussed.     

Plasma membrane of thymocytes--home of specific glucocorticoid binding sites

The incubation of rat thymocytes with 3H-cortisol in the presence of cortisol immobilized on polyvinylpyrrolidone (PVP-GC) produces a decrease in 3H-cortisol uptake by these cells. PVP-GC is shown to compete with cortisol for specific binding sites on thymocytes, without penetrating into cells. It is therefore, concluded that plasma membranes of thymocytes contain specific glucocorticoid binding sites.     

Analytical biotechnology of recombinant peptides and proteins: II. A confirmation of the primary structure of fusion protein containing human proinsulin and optimization of its proteolysis by trypsin

The kinetics of trypsin proteolysis of the fusion protein (FP) containing human proinsulin was studied by a set of analytical micromethods. These were the microcolumn reversed-phase HPLC and the qualitative identification by MALDI-TOF mass spectrometry and amino acid sequencing. The first stage of the proteolysis was shown to be the cleavage of FP into the leader fragment and proinsulin. The subsequent splitting off ofC-peptide from proinsulin results in the formation of Arg^B31-Arg^B32-insulin. The effect of temperature on the formation of de-Thr^B30-insulin, a by-product, was also studied. The structure of FP was confirmed by the peptide mapping technique, and the leader fragment was shown to contain noN-terminal Met residue. For communication I, see [1].     

Effects of nitroglycerin on intracellular concentration of calcium in human blood platelets]

It is shown that nitroglycerin has a calcium-blocking property in human platelets both at basal and ADP-induced calcium level, determined by fluorescence techniques (Fura-2). The study demonstrated a dose-dependent inhibitory effect of nitroglycerin on calcium rise, induced by ADP. 30-min preincubation with 60 microM nitroglycerin increased IC50 from 44 (without preincubation) to 320 microM, indicating the development of nitrate tolerance. It was suggested, that human platelet may be used as an experimental model of nitrate tolerance.     

Capacity of triterpene glycosides from holothurians to stimulate antibacterial resistance in a model of experimental murine salmonellosis

When injected intraperitoneally into mice in doses of 40.0-0.4 microgram, Cucumarioside, the preparation of triterpene glycosides obtained from sea cucumbers (Cusumaria japonica), enhanced the resistance of the animals to the subsequent challenge with Salmonella typhimurium. The study of the duration of the persistence of salmonellae in mice receiving the preparation in a dose of 0.001 microgram revealed a decrease in the contamination of their organs. The same dose of the preparation stimulated the phagocytic activity of peritoneal exudate cells with salmonellae showing decreased cytopathogenic action. This suggests that Cucumarioside enhances nonspecific protective factors, activates the macrophagal system and facilitates the development of complete phagocytosis.     

Immunomodulating activity of p-hydroxyphenyllactic and ascorbic acids

p-Hydroxyphenyl lactic acid (PHA) in a concentration of 5 . 10(-5) M produced a significant inhibition of cell proliferation in response to alloantigens in a one-way mixed lymphocyte culture (MLC) in colonic cancer patients and in blast transformation in response to suboptimal doses of Con A. Multiple administration of ascorbic acid in an optimal concentration to the culture increased the proliferative response of lymphocytes to alloantigens and Con A. PHA and ascorbic acid did not exhibit any immunomodulating action during the use of healthy donors' lymphocytes or lymphocytes from colonic cancer patients, transformed with optimal mitogen doses. PHA did not affect the production of cytotoxic T lymphocytes in the MLC of the spleens of allogeneic mice but inhibited lymphocyte proliferation in response to alloantigens in the MLC of the spleens obtained from B6 and vitamin A deficient animals.