The ratio of the types of gliocytes in the cerebellar cortex of mice during malnutrition and subsequent nutritional rehabilitation

Different types of glial cells were counted on the semithin sections on the area 0.5 mkm2 of the cerebellar cortex of mice and percent relation of glyocytes-satellites of glyocyte types was determined. The malnutrition in early postnatal life has been found to cause the aberration in the process of glyocytes differentiation, especially in the population of oligodendrocytes. After the food rehabilitatin the processes of differentiation normalize that expresses in the increase of proportion of olygodendrocytes and olygodendrocytes satellities up to the control.     

The specificity of an immune serum to the exocellular lipopolysaccharide of Pseudomonas wieringae

The serum obtained to exocellular lipopolysaccharide (ELPS) of Pseudomonas wieringae selectively agglutinated strains of pathovar of P. syringae and did not agglutinated strains of P. cichorii, P. solanacearum, P. gladioli pv. allicola, P. fluoroviolaceus, strains of nonphytopathogenic pseudomonads as well as bacteria of the genera Erwinia, Bacillus, Xanthomonas, Klebsiella. Consequently, the antigen determinant common with antigen of the species Pseudomonas syringae is present in the composition of ELPS.     

Adipokinetic hormone counteracts oxidative stress elicited in insects by hydrogen peroxide: in vivo and in vitro study

The role of adipokinetic hormone (AKH) in counteracting oxidative stress elicited in the insect body is studied in response to exogenously applied hydrogen peroxide, an important metabolite of oxidative processes. In vivo experiments reveal that the injection of hydrogen peroxide (8 µmol) into the haemocoel of the firebug, Pyrrhocoris apterus L. (Heteroptera: Pyrrhocoridae) increases the level of AKH by 2.8‐fold in the central nervous system (CNS) and by 3.8‐fold in the haemolymph. The injection of hydrogen peroxide also increases the mortality of experimental insects, whereas co‐injection of hydrogen peroxide with Pyrap‐AKH (40 pmol) reduces mortality to almost control levels. Importantly, an increase in haemolymph protein carbonyl levels (i.e. an oxidative stress biomarker) elicited by hydrogen peroxide is decreased by 3.6‐fold to control levels when hydrogen peroxide is co‐injected with Pyrap‐AKH. Similar results are obtained using in vitro experiments. Oxidative stress biomarkers such as malondialdehyde and protein carbonyls are significantly enhanced upon exposure of the isolated CNS to hydrogen peroxide in vitro, whereas co‐treatment of the CNS with hydrogen peroxide and Pyrap‐AKH reduces levels significantly. Moreover, a marked decrease in catalase activity compared with controls is recorded when the CNS is incubated with hydrogen peroxide. Incubation of the CNS with hydrogen peroxide and Pyrap‐AKH together curbs the negative effect on catalase activity. Taken together, the results of the present study provide strong support for the recently published data on the feedback regulation between oxidative stressors and AKH action, and implicate AKH in counteracting oxidative stress. The in vitro experiments should facilitate research on the mode of action of AKH in relation to oxidative stress, and could help clarify the key pathways involved in this process.     

Assessment of the activity of tumor necrosis factor in normal state and in ovarian tumors

The cytotoxic activity of tumor necrosis factor of healthy individuals and patients with cystadenoma and adenocarcinoma of ovaries was investigated. Tumor necrosis factor (TNF) spontaneous activities of healthy donors and patients with cystadenoma of ovaries was the same. The level of TNF spontaneous activity of patients with adenocarcinoma was increased. LPS-induced TNF cytotoxicity in patients with cystadenoma was decreased. Mononuclear cells of patients with adenocarcinoma did not respond to LPS stimulation by increased TNF production.     

Various methodological approaches in controlled screening of antibiotic producers among the group of Coryneform bacteria]

A methodical system for directed screening of cultures producing broad-spectrum antibiotics among soil saprophytic coryneform bacteria was developed. To isolate such cultures, it was recommended to use the glucose-yeast medium supplemented with malt extract (No. 18/3) and soybean-glucose medium with sodium sulfate and cobalt chloride (No. 20/3). The preliminary alkaline treatment of the soil substrates and the use of acidic soil samples were found to favour isolation of the Mycobacterium type cultures. It was recommended to use gram-negative tests microbes with relatively low antibiotic resistance for screening cultures producing broad spectrum antibiotics. Various agarized and liquid fermentation media were compared in regard to detection of antibiotic activity in the soil coryneform bacteria. The corn medium supplemented with protein-vitamin concentrate, glucose, lactose and starch (No. 116) proved to be the most efficient.     

The drug resistance and DNA plasmid profiles of Shigella dysenteriae 1 in the USSR and abroad

The medicinal resistance and plasmid profiles of 62 S. dysenteriae strains 1, isolated in the USSR in 1986-1988 from Soviet and foreign citizens (from Afghanistan, Vietnam) and 8 strains obtained from India in 1987 were studied. Pronounced similarity between the phenotypes of medicinal, including conjugative, resistance in the strains of Soviet and foreign origin was established. In the Soviet S. dysenteriae strains 1 the presence of two main types of plasmid DNA profiles (140, 6, 4, 2 MD and 140, 35, 6, 2 MD), similar to those in the strains of Afghan and Indian origin, was shown. In the Vietnamese strain the plasmid DNA profile was found to be quite different (70, 35, 6, 2 MD). Similarity between the phenotypes of medicinal resistance and the plasmid DNA profiles in the Soviet, Afghan and Indian strains under study indicated that the intensive and permanent penetration of the infective agents of Grigor'ev-Shiga dysentery from Afghanistan to the territory of the USSR, especially to Uzbekistan, occurred during the period of the stay of Soviet troops in Afghanistan.     

Various properties of cathepsin G and elastase from swine peripheral blood neutrophils

Using gel filtration through Sephadex G-100 and bioaffinity chromatography on contrical-Sepharose, cathepsin G and elastase were isolated from pig peripheral blood neutrophil granules and purified to homogeneity. Both enzymes hydrolyzed the total histone from calf thymus as well as synthetic substrates--tert-butoxy-L-alanine p-nitrophenyl ester (elastase) and benzoyltyrosine ethyl ester (cathepsin G). The use of natural and synthetic protease inhibitors showed that both enzymes were related to the group of serine proteases. The molecular mass of the cathepsin G subunit as determined by SDS polyacrylamide gel electrophoresis is 28-29 kD, that of elastase--30-31 kD. The pH optima for the hydrolysis of proteinaceous and synthetic substrates for cathepsin G and elastase are 8.0-8.5 and 7.0-7.5, respectively. The isoelectric points for elastase and cathepsin G are 9.7-10.0 and greater than 10, respectively; the temperature optima--30-40 degrees C and 50-60 degrees C, respectively. The amino acid composition of the two enzymes from pig granulocytes revealed a high content of arginine and was similar to that of human granulocytes.     

Study methods for localizing enzymes in the cells of gram-negative bacteria (a review)

The present review systematizes the literature data on localization of enzymes in cells of Gram-negative bacteria. It centres round the methods used for studying the enzyme localization. The criteria according to which one can locate an enzyme in bacterial cells are discussed.