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Biomedical subjects

V F Bulk

Publications and source records attributed to V F Bulk.

At least 19 recordsLinked to original sources
PubMed1992

[The use of monolaurates for removing endotoxins from preparations of cell-free pertussis vaccine].

The possibility of using monolaurates for removing endotoxin from acellular pertussis vaccines developed at the Laboratory of Immunomodulators, Mechnikov Research Institute for Vaccines and Sera (Moscow), has been studied. Monolaurates PEG-400 and PEG-600 obtained, respectively, from Fluka Chemie AG and Ferak GmbH (Germany) have been used. The use of monolaurate PEG-600 ensures the decrease of the toxicity of acellular pertussis vaccines by 2.34-6.3 times.

Animals↗
PubMed1988

[The growth and protein A accumulation of Staphylococcus aureus A-676 on a medium made from nonfood raw material].

In this research the experimental analytical method of balancing culture media, based on the determination of the yield of the target product, i.e. staphylococcal protein A, has been used. The medium, developed in the course of this research work on the basis of a hydrolysate of protein-containing waste products of the tanning industry, makes it possible to achieve the growth of producer strains similar to that achieved in peptone-yeast medium. The parameters of the growth of S. aureus strain A-676 and the biological activity of protein A obtained in the newly developed medium have been studied.

Bacteriological Techniques↗
PubMed1987

[Cell-free Pseudomonas vaccine: its immunochemical characteristics and immunogenicity].

Two variants of cell-free protein vaccine have been prepared from the mixture of 4 P. aeruginosa strains, serovars 02, 06, 07 and 011, and from a single P. aeruginosa strain, serovar 02. The preparation contains proteins with molecular weight ranging from 20,000 to 100,000 and the admixture of lipopolysaccharide in negligible amounts (not exceeding 0.08% of dry weight). The vaccine produces no signs of toxicosis in laboratory animals. The vaccine effectively protects mice challenged with P. aeruginosa of different O-serotypes and stimulates the formation of specific protective antibodies in rabbits.

Animals↗
PubMed1987

[Determination of ovalbumin-specific IgG antibodies in mouse sera by immunoenzyme analysis using horseradish peroxidase-conjugated staphylococcal protein A].

The article deals with the possibility of using staphylococcal protein A conjugated with horse-radish peroxidase for the detection of specific IgG-antibodies to ovalbumin in mice by the indirect and competitive EIA techniques. Studies on specifying the parameters of the EIA system for the detection of specific IgG-antibodies are in progress.

Animals↗
PubMed1987

[Immunoenzyme test system for the quantitative determination of tetanus antitoxin in vaccinated persons using horseradish peroxidase-conjugated staphylococcal protein A].

An enzyme immunoassay (EIA) system for assays of tetanus antitoxin in vaccinees has been developed. As conjugate, staphylococcal protein A labeled with horse-radish peroxidase is used in this system. The possibility of using the newly developed EIA system in seroepidemiological surveys of the population is shown.

Adult↗
PubMed1986

Immunochemical and immunological study of cell-wall proteins of Pseudomonas aeruginosa.

Crude aqueous extract was obtained from acetone-dried cells of Pseudomonas aeruginosa strain 868 (serogroup O2, Lányi and Bergan's schema) and subjected to ultracentrifugation (105,000 g, 3 h); the lipopolysaccharide (LPS)-containing precipitate was discarded and the supernatant containing water-soluble cell proteins was subjected to further fractionation. From a partially purified aqueous extract two fractions were obtained by step-wise precipitation with ammonium sulphate, namely, F1 (by 50% saturation), and F2 (by 80% saturation). By gel and ion-exchange chromatography from both fractions 9 subfractions were isolated differing in molecular weight, protein content, and LPS contamination. Subfractions 4 and 7 were practically free from LPS, and gave one precipitation line with antisera for strain 868. By immunoelectrophoresis subfraction 4 contained 2 cathodic and 1 anodic, whereas subfraction 7 mainly 1 anodic component. These subfractions were antigenically identical. With ELISA these subfractions were less active as compared to other subfractions, in particular to those of high molecular weight. The anti-subfraction 4 and anti-subfraction 7 sera were found to protect passively mice against intraperitoneal challenge by P. aeruginosa strain 8 (serogroup O2). These data support the authors' opinion that subfraction SF-4 and SF-7 are protective protein antigens (mol wt about 40,000 and 30,000, respectively), that are localized in the outer membrane of P. aeruginosa cell envelope.

Animals↗
PubMed1986

[Possibility of inactivation by formalin of staphylococcal protein A at different stages of its production].

The possibility of the formalin inactivation of material containing staphylococcal protein A in the process of obtaining the preparation has been studied. The inactivation of the material with formalin at a concentration of 5% (from the volume of the material) for 1 hour has been shown to ensure a complete bacteriostatic effect and the stability of the initial biological activity of staphylococcal protein A.

Drug Stability↗
PubMed1985

[Dynamics of staphylococcal infection in guinea pigs with delayed hypersensitivity to Staphylococcus aureus surface antigens].

The relationship between delayed hypersensitivity (DH) to S. aureus surface antigens and the intensity of the infectious process induced by the sublethal infection of guinea pigs with S. aureus was studied. The protective effect, manifested by a decrease in the staphylococcal contamination of the spleen tissue and by an increase in the level of the activation of lymphocytes, was shown to correlate with DH induced by inactivated staphylococcal cells. In infected guinea pigs having DH to different staphylococcal antigens the disease either took a more severe course (in cases of DH to cell wall or peptidoglycan) than in the animals subjected only to infection, or no aggravation of the disease was observed (in cases of DH to protein A).

Animals↗
PubMed1985

[Protective protein antigens of Pseudomonas aeruginosa].

Partially purified water extract was obtained from the initial water extract by ultracentrifugation. Nine protein fractions differing in molecular weight, homogeneity and the content of lipopolysaccharide (LPS) were obtained by stepwise precipitation with ammonium sulfate and subsequent fractionation in columns packed with Sephadex G-100 and DEAE cellulose. Two protein fractions with a molecular weight of 30000 and 40000 daltons were practically free of LPS. These fractions were homogeneous as shown by analytical centrifugation and formed a single precipitation line with P. aeruginosa antiserum; both fractions were found to be antigenically identical. In the enzyme immunoassay these two fractions proved to be least active in comparison with the other protein fractions, but when used for the immunization of rabbits, they induced the formation of specific protective (for mice) antibodies. Both antisera were equally active in the experiments of the passive protection of mice. The isolated LPS-free proteins are supposed to be the proteins of the outer membrane of P. aeruginosa cell wall and have the properties of protective antigens.

Animals↗
PubMed1985

[Staphylococcal infection in guinea pigs with enhanced delayed hypersensitivity induced by Staphylococcus aureus surface antigens].

A comparative study was made of the relationship between the DHS phenomenon and certain staphylococcal antigens and the intensity of infectious process in sublethal infection of guinea-pigs by Staphylococcus aureus. The protective effect, which was manifested by reduced amounts of staphylococcal colonies in spleen tissues and elevated level of lymphocytes, and neutrophil activation, correlated with DHS induced by surface antigens under study (cell wall, peptidoglycan, protein A). Incomplete combination or certain antigens induced DHS but did not increase the resistance to the following infection.

Animals↗
PubMed1984

[Use of different media for growing the producer of the restriction enzyme XBA I].

The possibility of using culture media prepared from local ingredients and intended for growing the producers of restricting enzyme Xba 1 has been demonstrated. The yield of restricting enzyme Xba 1 per g of crude biomass, obtained with the use of peptone-yeast medium prepared from ingredients supplied by Difco Laboratories (USA), has proved to be 4 times greater than that obtained with the use of peptone-yeast medium prepared from local ingredients. At the same time the use of casein-saline medium ensures the yield of the enzyme, similar to that obtained with the use of peptone-yeast medium prepared from ingredients supplied by Difco Laboratories, but with a greater content of nonspecific nucleases.

Culture Media↗
PubMed1982

[Elaboration of a method of stabilizing the protective fraction of pertussis microbes].

A method for stabilizing adsorbed preparations of the protective fraction of B. pertussis has been developed; according to this method, a colloid suspension of protective protein in phosphate buffer is obtained, the protein is then adsorbed on aluminium hydroxide gel and lyophilized with 10% of sucrose. If stored at 4 degrees C, these dried preparations have been found to retain their immunogenicity for 1 year.

Adsorption↗
PubMed1982

[Cell-free Pseudomonas vaccine. IV. Laboratory trials of the effectiveness of experimental Pseudomonas vaccines].

Partially purified water-soluble cellular protein antigens have been obtained from 2 newly isolated P. aeruginosa strains and 1 museum P. aeruginosa strain, belonging to immunotypes 2, 3 and 7, by the method of preparative ultracentrifugation. Such trivalent P. aeruginosa vaccine (PV) has proved to be effective in direct and cross experiments of the active protection of mice. The method of ultrafiltration has been used to prepare monovalent PV from a newly isolated strain belonging to immunotype 3/7. This monovalent PV has been found to stimulate immunity to infection with homologous or heterologous P. aeruginosa strains in mice. The comparison of the results obtained in the study of PV prepared by the methods of ultracentrifugation and ultrafiltration suggests that both these methods for the isolation and purification of P. aeruginosa protective protein antigens are equally effective.

Animals↗