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S N Cherenkevich

Publications and source records attributed to S N Cherenkevich.

67 records · Page 4Linked to original sources
PubMedDate not supplied

[Study of temperature-dependent conformational changes in serum albumin using an adsorbed dye].

4-N (p-sulfoaniline),5-methoxy,1,2-benzoquinon (1) is bound by hydrophobic regions of the native molecule of bovine serum albumin (BSA). In the temperature interval 0--65 degrees C the interaction characteristics such as energy, entropy and the average number of the binding sites on a BSA molecule were determined. Under experimental conditions BSA is found in at least in two equilibrium conformational states distinguished by quantity of hydrophobic regions capable of binding with 1. Below 17 degrees C no conformational changes of BSA was observed. With the increase of temperature from 17 to 47 degrees C the equilibrium is driven in the direction of protein form with the hydrophobic binding sites which are more available for the solvent. Heating above 47 degrees C produces "predenaturation" structural changes in the BSA molecule. Hydrophobic regions of the BSA have different thermal stability.

Benzenesulfonates↗
PubMedDate not supplied

[Effect of ozone on the permeability of flat bilayer lipid membranes].

The influence of the liposome ozonolysis products on ionic permeability and stability of the planar bilayer lipid membrane ( PBLM ) was studied by electroconductivity . Addition of ozonized liposomes and PBLM preparation from the products of the ozonized lipids results in a decrease of the PBLM resistance. It is suggested that the enhancement of PBLM stability from ozonized lipids may be caused by production during lipid peroxidation of the intermolecular bonds between lipid molecules and by an increase of the lipid bilayer rigidity.

Electric Conductivity↗
PubMedDate not supplied

[Lipid peroxidation and development of dystrophic changes in the intervertebral disks during atherosclerosis].

Lipoproteins of intervertebral discs, spinal cord and blood were studied spectrofluorimetrically in experimental atherosclerosis. Lipoproteins and hydroperoxides accumulated in the intervertebral discs under dystrophic conditions. Blood serum lipoproteins were involved in pathogenesis of these atheromatous impairments in the intervertebral discs. Content of lipoproteins in the discs might be normalized by means of diet-fasting therapy.

Animals↗
PubMedDate not supplied

[H2O2 generation and human neutrophil aggregation as affected by lectins].

The effects of eight plant lectins on human neutrophils aggregation and H2O2 release were studied. Both processes were stimulated by lectins from Viscum album, Triticum vulgaris, Phaseolus vulgaris and Canavalia ensiformis while lectins from Solanum tuberosum, Sambucus nigra and Glycine mas displayed only aggregating activity and Arachis hypogaea lectin was not effective. Heating (46 degrees C) and UV-radiation during 4-5 min were found to suppress completely H2O2 release from neutrophils keeping the capacity of cells to be aggregated. The findings indicate that lectin-induced human neutrophils aggregation is necessary but not sufficient condition of respiratory burst of cells. The comparison of the aggregating activity of lectins with their ability to induce the H2O2 release is supposed to be the basis of screening of lectins with antitumor and immunomodulatory activity.

Cell Aggregation↗
PubMedDate not supplied

[The effect of hyperthermia (45 C) on lymphoid cell aggregation].

Hyperthermia (45 degrees C) has found to decrease the rate of rat thymocytes as well as splenocytes aggregation induced by lectins (concanavalin A, wheat germ agglutinin) and sulphated polysaccharides (heparin, dextran sulphate-500) and to increase those induced by cationic dye alcian blue. Shedding of plasma membrane glycoproteins and changes of surface charge are supposed to affect the aggregation.

Alcian Blue↗
PubMedDate not supplied

[The effect of metabolic inhibitors on resistance of mannose-specific contacts of Escherichia coli K12 and human neutrophils].

Human neutrophil aggregation induced by Escherichia coli K12 cells has been studied. D-mannose has been found to inhibit the process in the dose-dependent way causing the full blockage at 10 mM concentration. The process of disaggregation induced by the concentration is significantly higher at 10 degrees C than at 37 degrees C. The inhibitors of cellular oxygenation such as N-ethylmaleimide, nordihydroguaiaretic acid, trifluoperazine, and colchicine did not affect the aggregation process. Cellular aggregation was concomitant with production of H2O2, and this reaction was also blocked by D-mannose and depended on the number of bacteria present. The nordihydroguaiaretic acid and N-ethylmaleimide inhibited production of H2O2, while sodium azide enhanced the process. The results show the mannose-specific contact of bacteria and neutrophils to depend on the functional activity of phagocytes including their ability to produce H2O2.

Cell Aggregation↗
PubMedDate not supplied

[The effect of recombinant interleukin-1 beta on concanavalin A-induced lymphocyte reactions].

As revealed by investigations made by the use of the method of luminol-dependent chemiluminescence and light dispersion, the addition of concanavalin A (ConA) to the suspension of human peripheral blood lymphocytes and subsequent incubation with recombinant interleukin-1 beta leads to a sharp increase in the yield of chemiluminescence and the rate of cell aggregation in comparison with similar parameters obtained for cells, not treated with interleukin-1 beta. The study revealed the potentiating action of recombinant interleukin-1 beta on ConA-induced proliferative response of thymocytes in the culture. The mechanisms of the priming action of recombinant interleukin-1 beta on ConA-induced reaction of lymphocytes are discussed.

Animals↗
PubMedDate not supplied

[The free-radical mechanisms of the cytotoxic action of 1,2-benzoquinone derivatives].

The authors examined the interaction of 1,2-benzoquinone derivatives with HeLa cell cultures and ascite Ehrlich's cancer cells. 4-N (anilino)-5-methoxy-1,2-benzoquinone was found to produce a marked toxic effects against tumor cells. The cytotoxic effect is oxygen dependent and associated with the formation of oxygen radicals in quinone's redox cyclization reactions. The inhibitory analysis was used to show that the major mediators of the toxic action of the agent are superoxide radical-anion and hydrogen peroxide. It is concluded that the interaction of highly toxic oxygen radicals, which are generated in quinone redox cyclization, with plasma membrane cells is likely to be the mechanism responsible for cellular destruction when quinones act on tumor cells.

Animals↗
PubMedDate not supplied

[Relationship between the oxidation-reduction system of astrocytes with production of active forms of oxygen].

Cells of neuroglia--the astrocytes are of interest from the point of view of their participation in phagocytosis. Phagocyte ability to generate active oxygen forms (AOF) as used as the basic criterion of the estimation of their functional activity. For the purpose to clear up molecular and cellular mechanisms of phagocytosis a study of astrocyte redox-systems, participating in production of AOF, was undertaken. Registration of AOF in astrocytes was carried out using a method of luminol-dependent chemiluminescence. Primary culture of guinea pig astrocytes was used. Spontaneous chemiluminescence of low intensity was found for the astrocytes at the presence of luminol. The destruction of the cells was accompanied by a significant growth of the intensity of spontaneous chemiluminescence. Suspension of endocutosis inductors, particle of latex and phytohemagglutinin, added to astrocytes did not result in formation of AOF, characteristic for other cells, possessing phagocytosis. It was established, that addition of hydrogen peroxide destroys astrocytes at the presence of luminol and gives rise to the emission. Chemiluminescence was not observed in similar experiments with intact cells. A conclusion was made that inside astrocytes there are structures, which show peroxidase-like activity.

Animals↗