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N N Sukhareva

Publications and source records attributed to N N Sukhareva.

18 recordsLinked to original sources

[Composition and immunological activity of membrane-bound surface glycoprotein from Crithidia oncopelti].

A membrane-bound glycoprotein with a molecular weight of 10000-12000 was isolated from Crithidia oncopelti and purified. The glycoprotein contained peptide, carbohydrate and lipid fragments and phosphorus. The peptide fragment was represented by 10 amino acids. The carbohydrate fragment was represented by 7 monosaccharides. The lipid part was mainly represented by stearic acid. The glycoprotein showed immunostimulating properties. It had a comitogenic effect on murine spleen cells in vitro and induced tumoricidal activity in murine peritoneal macrophages in vitro and in vivo.

Adjuvants, Immunologic↗

[Rubro-caudate projections in the cat].

A few neurons projecting to the caudate nucleus were found in the cat red nucleus by the horse-radish peroxidase (HRP) method. Rubro-caudate neurons were observed both in the magnocellular and parvocellular parts of the red nucleus. Organization of the reciprocal connections of red nucleus and striopallidal system is discussed.

Animals↗

[Astasian: A new stimulator of peritoneal macrophages].

Immunological properties of astasin, a novel substance isolated from Astasia longa was studied. 3-4 days after intraperitoneal administration of astasin in a dose of 1000 micrograms per a mouse (50 mg/kg) in the form of suspension in physiological solution or gel in dimethylsulfoxide there was observed maximum increase in the number of the Fc-receptor cells of the macrophage plasmatic membranes and intensity of sheep red blood cell phagocytosis (3.6-4 and 3.2-4-fold, respectively). Dimethylsulfoxide solution of astasin increased migration of the cells into the abdominal cavity by 5.8 times. The respective figure for the astasin suspension was 28. times. Therefore, differences in the nature of the effect and quantitative indices after the exposure to astasin in the above two forms were observed. Sodium chloride isotonic solution of astasin had a retarded but more prolonged effect on the macrophages which was probably due to gradual digestion of the polysaccharide phagocyted granules by the macrophages.

Animals↗

[Effect of astasilid on the stimulation of peritoneal macrophages].

The effect of astasilid, a sucrose monoester and the effect of mainly unsaturated fatty acids from the lipid fraction of Astasia longa on immunocompetent cells--macrophages of the mouse peritoneal cavity were studied. It was shown that astasilid increased 7.5-8.5-fold expression of Fc-receptors on the macrophage plasmic membranes and stimulated 5.5-6.5-fold the macrophage capacity for Fc-dependent phagocytosis of sheep red blood cells. Astasilid had no effect on migration of the macrophages into the abdominal cavity.

Adjuvants, Immunologic↗

[Trypanosome sensitivity to polyene antibiotics].

Swelling of the plasma membrane is one of the mechanisms of resistance to damages in pathogenic Protozoa. Polyenic antibiotics induce reconstruction of the cytoplasma membrane of unicellular eukaryotic organisms, i. e. fungi and Protozoa by binding the membrane lipids. The effect of 5 heptaene polyenic antibiotics, such as amphotericin B, mycoheptin, levorin, its sodium salt and levoridone on the growth of trypanosomides of Trypanosoma lewisi and Crithidia oncopelti was studied. The MIC and IC50 of these antibiotics were determined. It was found that these antibiotics were inhibitors of the trypanosomide growth and development. Levorin and amphotericin were most active with respect to C. oncopelti and levorin was most active with respect to T. lewisi. Physiological and morphological changes in the trypanosomides induced by the polyenic antibiotics were noted. The effect of levorin and amphotericin B on the content of lipids in the trypanosomide cells was studied. A decrease in the total content of the intracellular lipids due to the effect of the polyenes was shown. Differences in the rate of the inhibitory effect as dependent on the structure of the hydrophile part of the lactone ring of the heptaene polyenic antibiotics were found.

Anti-Bacterial Agents↗

[Effect of lipid preparations isolated from protozoa on experimental leishmaniasis in golden hamsters].

The effect of lipid preparations Nos. 59 and 60 isolated from Protozoa on experimental leishmaniosis of golden hamsters was studied. Preparations Nos. 59 and 60 are water-soluble derivatives of fatty acids isolated from Trypanosoma lewisi and Astasia longa respectively. It was found that both preparations administered to the animals simultaneously with the causative agent or after formation of the leishmaniosis infiltrates inhibited the development of the disease clinical signs. Such an effect of the preparations was observed only during the period of the animals exposure to them. After discontinuation of the treatment the development of the clinical process proceeded the same as in the control animals. The lipid preparation No. 60 differing from preparation No. 59 by high content of C20-poly-unsaturated fatty acids was more active and induced a significant decrease in the size of the leishmaniosis infiltrates formed. Preparation No. 60 was more effective in the treatment of the animals infected with L. tropica major than in the animals infected with L. tropica minor. Preparation No. 59 had no significant effect on multiplication and morphology of the parazites.

Animals↗

[The suppression of the chemiluminescence of mammalian cells by the metabolites of Crithidia oncopelti].

Effect of water-soluble (polypeptides) fraction (PF) of Crithidia oncopelti on the chemiluminescence of human blood cells and murine splenocytes was studied. The study has shown that PF possessed a capacity to inhibit oxygen-dependent killer system of polymorphonuclear leucocytes in dose-dependent manner. This effect was of a complex nature. The inhibitory effect of PF was demonstrated also in respect to murine mononuclear phagocytes and splenocytes. It was suggested that, in this case, the suppressor effect was related with the influence on membranous cytokines.

Animals↗

[The trypanocidal action of fluorouracil on Crithidia oncopelti in the presence of lipid metabolic modifiers].

Effect of fluorouracil in combination with ascorbate and L-valin, modifiers of lipid metabolism was studied in cultured protozoa Crithidia oncopelti. The inhibitory effect of preparation in a concentration of 100 mcg/ml gradually decreased in the course of cultivation. Its readdition to a 96-hour culture did not increase its effect on protozoa cells. Combined addition of fluorouracil and modifiers (100 mcg/ml each) resulted in insignificant decrease of the cell accumulation in the culture as compared with the effect of fluorouracil alone. When fluorouracil and modifiers were readded to the 96-hour culture, the trypanostatic effect of preparation was 2.5 times enhanced. This enhancement was confirmed by destructive alterations in cell morphology and by the culture lysis by 192 h of protozoa cultivation.

Animals↗

[New biologically active substances from protozoa and an evaluation of their action].

Novel biologically active substances were obtained from nonpathogenic for humans and free-living protozoa: Crithidia oncopelti, Trypanosoma lewisi, and Astasia longa. There were studied conditions of biosynthesis, composition and biological activity of the total lipid fraction from the protozoa species, sucrose ethers and fatty acids, the latter were isolated from A. longa--(astazilide preparation), reserve beta-1,3 glucan from A. longa (astazian preparation), and fraction of surface glycophospholipids and peptides from Crithidia oncopelti (GLP preparation). Two of three preparations studied (astazilide and GLP) are the complexes of natural substances with certain composition. Conditions of the protozoa cultivation were developed to provide standardization of the complex composition. Division of the complexes into separate components decreased or abolished the biological activity. It was established that the substances studied modify biological reactions, that is exert a systemic effect. They may be used for inhibiting the growth of experimental tumors and preventing the metastatic spreading in tumor-carrier animals. The substances obtained belong to the group of nonspecific stimulators for cellular immunity which can be used in medicine, veterinary medicine, food industry, pharmacologic industry and cosmetology.

Adjuvants, Immunologic↗

[The biological activity of complex esters of saccharose and higher fatty acids].

Sucrose/fatty acid ethers from Astasia longa culture have been studied. Biological activity of different ethers has been studied on calf kidney cells. The activity depends on the lipid component of the ethers. The highest stimulation of cell layer formation was observed with ethers of sucrose and polyunsaturated fatty acids.

Animals↗

[The membrane-bound surface glycoprotein of Crithidia oncopelti].

Membrane-associated surface glycoprotein from Crithidia oncopelti (MAG) has been isolated and studied. Its molecular weight constitutes 10-12 kDa. MAG contains 12% protein, 29% carbohydrates, 1.2% phosphate and a lipid fragment. Amino acid components of MAG include glutamine, asparagine, alanine, proline, valine, leucine, serine, threonine, lysine, glycine. Ethanolamine and glycerophosphate have also been found. MAG contains stearic and small amounts of palmitic, oleic and myristic fatty acids. Carbohydrate fragment of MAG consists of seven monomers.

Amino Acids↗

[The use of preparations of protozoan origin as agents for the prevention and early therapy of combined radiation-thermal injuries].

Radioprotective and therapeutic effects of astazian and astazilide, the drugs of protozoan origin, were studied in comparison with known modifiers of biological reactions (bacterial polysaccharides, synthetic polypeptides) in combined radiation-thermal injuries (CRTI). The efficiency of drugs under examination was found to be time- and dose-dependent. Application of the drugs of protozoan nature 24 hours prior to or 1 hour following CRTI provided 30 to 50% survival of experimental animals for 30 days as compared to 4.5% in the group of untreated mice. Administration of the drugs 3-7 days following CRTI exerted no therapeutic effect.

Animals↗

[The embryotoxic action of fragment C-I-6 of human interleukin-2].

The peptide C-I-6 is a modified fragment (sequence 59-72) of human interleukin-2 and stimulates regeneration of hepatic cells and tissues. Study of the possible embryotoxic and teratogenic properties of C-I-6 showed that in some cases it induces the following statistically significant changes: reduces the number of viable fetus, increases the occurrence of hydronephrosis and the number of external and internal hematomas, increases the weight and size of the embryo. It is concluded that intraperitoneal administration of C-I-6 causes a mild embryotoxic and teratogenic effect in rats.

Animals↗