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A study is made on a strain of higher basydiomycete Flammulia velutipes (Fr.) P. Karat. The conditions of maximum biomass production by Flammulia velutipes were studied. Soluble and insoluble fractions were isolated from mycelium. The composition of cultured mycelium and aqueous extracts from mycelium were investigated. These objects mainly contained carbohydrates (65.3 and 84.0% in insoluble and soluble fractions, respectively, and 56% mycelium), proteins (7.5-10.0% in fractions and 17.5% in mycelium), as well as an insignificant amount of mineral substances. The main carbohydrate component of fractions was glucose (53.6-78.8%); galactose and mannose were also present, as well as fucose and xylose in insignificant amounts. The aqueous extracts from mycelium demonstrated immunomodulating activity. They rendered a stimulating effect on the functional activity of macrophages--central cells of the reticluoendothelial system. The soluble fraction had a more pronounced effect than the insoluble fraction.

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It was demonstrated that passive immunization of pregnant female rats against MP65 and ACBP14/18 proteins leads to stable changes in offspring behavior (deviations in acquisition of active avoidance in a shuttle-box and changes in the open-field behavior). Immunomorphological data about localization of MP65 and ACBP14/18 proteins in brain slices of adult rats and rat embryos are presented. The obtained results are discussed in terms of the influence of maternal humoral immunity on the formation of fetal nervous system during intrauterine development.

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The ability of yeast exoglycans (from Cryptococcus laurentii, Cr. luteolus, and Sporobolomyces albo-rubescens) to absorb copper and lead ions has been studied. The sorption isotherms have been obtained, which indicates that the mechanism of interactions in the system polysaccharide-metal is complex. For the majority of the glycans, the absorption selectivity was considerably higher in the case of copper, as compared to lead. The observed discrepancy in the effects of pH and temperature on the absorption indicates that the bonds mediating ion absorption by glycans are of different nature. In conclusion, yeast exoglycans are efficient sorbents of copper and lead ions, and lutelan is the most active exoglycan in this respect.

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In vitro experiments were shown that native ecologically pure non-starch polysaccharide crylan bind the bile acid. Crylan was found to decrease hyperlipidemia induced in rats by means of diet enriched with cholesterol and 6-methylthiouracil. This effect of crylan was more pronounced as compare with the action of native nonspecific enterosorbent polyfepan.

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It was shown that the effect of polysaccharides such as hetero- and homoglycans, polyuronides and neutral polysaccharides on the functional status of macrophages was different by the activation level. The activity of the polysaccharides depended on the charge and polymeric properties of the molecules, glycoside bond configuration and supermolecular structure.

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Extracellular polysaccharides produced by some Cryptococcus species have been structurally investigated. These polymers have identical core structure, which was found to be alpha-1,3-mannan and different degrees of substitution of mannose in the core by xylose and glucuronic acid residues of side chains and different composition of side chains. Heteropolysaccharide from Cr. humicolus, the simplest one, has the same structure as the Cr. neoformans serotype D capsular polysaccharide. The Cr. skinneri polymer proved to be the most branched among Cryptococcus polysaccharides.

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Characteristics of the fraction composition of extracellular mannan produced by Rhodotorula rubra are presented. Various lots of the polysaccharide mainly contained two fractions similar by their chemical structures and differing in the solution relative viscosity. HPLC was used for determining the molecular weight of the samples. In the isolated fractions it differed 3-5 fold. Relationship between the fibrinolytic activity of the polysaccharide and its molecular weight was revealed. The samples of mannan with the molecular weight of 400-500 kD had the highest capacity for lowering the fibrinogen blood levels in rats. The polysaccharide with the molecular weight of less than 100 kD had practically no fibrinolytic activity.

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The effect of various carbon and nitrogen sources on the synthesis of the branched exopolysaccharide produced by Cryptococcus laurentii st 1803-K. was studied. The conditions favourable for a higher yield of the polymer were found. The carbon and nitrogen sources used do not affect the qualitative monosaccharide composition of the polysaccharide, however, the introduction of ammonium salts in the medium can cause a change in the monosaccharide ratio in the side chains of the polymer.

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The antimicrobial effect of cationic and anionic surface-active substances, i.e. catamine AB and sulphonol NP-3 respectively was studied in vitro with respect to gramnegative bacteria. In non-bactericidal concentrations catamine AB significantly increased the efficacy of tetracyclines, while the anionic compound had no such effect. The increase in the tetracycline activity was due to the antibiotic increased absorption (14C-oxytetracycline as an example) on the treatment of gramnegative bacteria with catamine AB and staphylococci with catamine AB and sulphonol NP-3, which was mainly associated with impairement of the cell membrane permeability by the surface-active substances.

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The antimicrobial effect of cationic surface-active substances, such as cetylpyridinyi chloride, alkylmethylbenzylammonium chloride ("roccal" and "catamine AB") and chlorhexidine was studied in vitro. The above compounds had a high bactericidal activity against poly-resistant staphylococcal strains. In non-bactericidal concentrations they significantly increased the efficacy of antibiotcs with different modes of action, i.e. penicillins, tetracyclines, amino-glycosides, macrolides. The effect of the cationic surface-active substances increasing the antibiotic activity against staphylococci did not depend on the resistance type, i.e. chromosomal or extrachromosomal. This was mainly associated with impairement of the function of the bacterial cytoplasmic membrane by these compounds. The cationic surface-active compounds were poor inhibitors of the specific enzyme of Bac. licheninformis 749/C, i.e. penicillinase. A marked inhibition of the enzyme was observed only at concentrations above the bactericidal ones and those damaging the cell membrane of staphylococci.

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The influence of catamine AB, sulfonol NP-3, sodium alkylsulfate homologues (C10-C16) and of syntanol DT-7 on the reaction of fibrin formation under the action of the partially purified coagulase was studied. Catamine and sulfonol inhibited the velocity of the reaction in the the concentrations over 0.002 and 0.01%, respectively. A reduction of the rate of reaction with catamine occurred chiefly as a result of the enzyme inactivation, whereas sulfonal influenced the intermediate products of the reaction. Inhibition of the rate of the reaction with the sodium alkylsulfate homologues was enhanced with the increase of the alkyl radical length and was the greatest for the tetradecyl sulfate sodium. Syntanol failed to influence the enzyme activity, but increased its amount in the staphylococcus culture on the medium with subbacteriostatic concentrations of sulfactants. Catamine, sulfonol and, to a lesser extent, syntanol retarded the coagulation process of human citrate plasma with pathogenic staphylococcus.

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