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I V Rubtsov

Publications and source records attributed to I V Rubtsov.

At least 37 records · Page 2Linked to original sources
PubMed1984

[Effect of gamma radiation on the immunobiological and immunochemical properties of cholera exotoxin. I. Change in the biological activity of nonpurified cholera exotoxin as affected by ionizing radiation].

Crude cholera exotoxin (filtrate toxin) was irradiated with increasing doses of gamma radiation. A significant drop in enterotoxicity, in the activity of the permeation factor and a decrease in toxicity were shown to occur as radiation doses increased. Radiation doses of 50-70 kGy were found to completely inactivate enterotoxicity in liquid toxic preparations. A higher radioresistance of dried preparations in comparison with liquid ones was registered: inactivation occurred at 150-200 kGy. Different batches of the initial filtrate toxin had varying radiosensitivity. The sterilizing effect of gamma radiation was achieved at doses of 20 kGy for liquid preparations and 30 kGy for dried preparations. During the prolonged storage of the irradiated preparations of crude toxin (the term of observation being 1.5 years) at different temperatures no reversion of toxicity was found to occur, while their immunogenic properties remained unchanged.

Animals↗
PubMed1983

[Quantitative determination of the soluble antigens of intestinal bacteria using a method of immunoenzyme analysis. I. Processing of the parameters of the method].

The parameters of the assay based on the quantitative evaluation of the neutralization of specific antibodies by the antigen under study and the subsequent detection of free antibodies on the fixed reference antigen with the aim of the quantitative determination of the specific O-antigens of Salmonella, groups D, B, C1, as well as those of Shigella sonnei and Shigella flexneri, have been developed. The proposed method makes it possible to detect the O-antigen of the causative agent at concentrations of 0.001 micrograms/ml to 100 micrograms/ml.

Antigens, Bacterial↗
PubMed1983

[Diagnostic test-system for the immunoenzymatic detection of meningococcal antigen].

To detect meningococcal antigen, the use of the enzyme-labeled immunosorbent assay (ELISA), a new variant of the immunoenzymatic method, permitting one to carry out quantitative analysis, is proposed. The optimum conditions for the test to detect group A meningococcal antigen, as well as the procedure for the approbation of the test on patients with meningococcal infection and on healthy persons, have been worked out. The method is shown to be highly specific and sensitive.

Animals↗
PubMed1983

[Surface antigen structure of Neisseria meningitidis. I. The isolation of a serotypic antigenic complex of N. meningitidis strain B16B6 by direct detergent treatment and its immunochemical characteristics].

The method for obtaining a serotyping antigenic complex from N. meningitidis B16B6 by their direct treatment with the mixture of detergents (0.5% sodium desoxycholate and 0,5% cholic acid in the proportion 1 : 1) in 0.5 M KCl solution is proposed. Such treatment has been found to increase the yield of the preparation in terms of protein more than 4 times in comparison with earlier methods for obtaining serotyping antigens. The immunochemical study of the preparation has demonstrated its serological specificity and high immunological activity, not inferior to that of serotyping antigenic preparations from group B meningococci, obtained by the heretofore known methods.

Antigens, Bacterial↗
PubMed1982

[Clinico-immunological indices in different forms of dysentery].

A total of 100 patients with acute dysentery and 12 patients with chronic dysentery have been examined. The capacity of lymphocytes for blast transformation and spontaneous rosette-formation has been found to depend on the stage, form and severity of the disease. In patients with low characteristics of the T-system of immunity at the acute stage of the disease slower convalescence is observed. When the clinical signs of the disease disappear, the characteristics of the T-system of immunity approach the normal level, but not quite reach it. In patients with a severe or prolonged course of dysentery the results of the leukocyte migration inhibition test either do not differ from the normal level, or indicate that the stimulation of leucocyte migration occurs.

Adult↗
PubMed1981

[Parameters for constructing a test system for the isoenzymatic detection of meningococcal antibodies].

The optimum conditions for the detection of specific humoral antibodies in patients with meningococcal infection by the immunoenzymatic method have been determined: the sensitizing dose of the antigen is 20 microgram of protein per 1 ml for group A meningococcal antigen and 25 microgram of protein per 1 ml for group C meningococcal antigen, the pH of the buffer solutions is 5.0-6.0 for group A meningococcal antigen and 12.0 for group C meningococcal antigen, the time and temperature of incubation should be 18-20 hours at 14 degrees C. The diagnostic test system developed in this research is capable of detecting antibodies with the accuracy of several ng.

Antibodies, Bacterial↗
PubMed1980

[Delayed hypersensitivity in the chronic cholera vibrio carrier state in animals with an absence of normal microflora].

The development of allergy in germ-free rats in chronic vibriocarriership was studied. The formation of specific delayed type hypersensitivity was found to occur to a limited extent in the animals devoid of normal microflora. The picture of hyperergic inflammation was revealed in the lymph nodes of vibriocarrier rats, the test for specific allergen being positive.

Allergens↗
PubMed1978

[Reactogenicity and immunological effectiveness study of a complex paratyphoid B antigen].

Reactogenic property and immunological efficacy of the paratyphoid preparation containing a complex of O-, K- and H-antigens obtained by single-stage antigens extraction were studied in a limited group of volunteers (22 persons). The antigen gave no untoward reactions and proved to be safe when given orally in doses of 25 to 150 mg. Paratyphoid B antigen was characterized by a marked immunization activity and stimulated formation of specific paratyphoid O-, K- and H-agglutinins and antibodies of the IgA,- IgG,- and IgM-classes.

Agglutinins↗
PubMed1978

[Study of Vibrio cholerae fractions. II. A comparison of the immunochemical and biological properties of preparations of alkaline extracts (vibrionin) and the endotoxin of Vibrio cholerae].

Comparative study of immuno-chemical and biological properties of vibrionin and cholera vibrio endotoxin showed vibrionin to contain up to 73.5% of protein, whereas endotoxin preparations contained only 25% of protein. Use of disc electrophoresis in polyacrylamide gel permitted to determine the relative electrophoretic mobility of the protein component bands of both preparations. Residual quantities of O-antigenic cholera vibrio determinants were revealed serologically in the vibrionin preparations. Study of biological properties of vibrionin (cholera allergen) demonstrated a possibility of using vibrionin in the capacity of a new bacterial allergen.

Animals↗
PubMed1978

[Study of Vibrio cholerae fractions. III. The gel chromatographic and immunochemical characteristics of vibrionin].

Three fractions differing by molecular weight (fraction 1--greater than 14 x 10(4)--less than 2 x 10(6) dalton, fraction 11--greater than 7 x 10(4)--less than 14 x 10(4) dalton, fraction III--greater than l0(4) less 35 x 10(3) dalton) were isolated from vibrionin, a preparation of cholera allergen, by gel chromatography on Sephadex G-150. These fractions possessed a different immunochemical activity and were capable of detecting the state of increased sensitivity to cholera vibrio.

Animals↗
PubMed1977

[Cholera vibrio fractions. I. Isolation of alkaline extracts of cholera vibrios and a study of their biological properties].

The authors suggest a well-reproducible method of preparation of a biologically-active fraction of an alkaline extract of cholera vibrio from the strain 569B of Inaba serological type consisting in a preliminary triple removal of endotoxin (O-antigen) of the causative agent from the microbial cell suspension with trichloracetic acid with the subsequent extraction of the microbial mass and neutralization of the extract obtained capable of effective detection of the state of specific sensitization of the organism to cholera vibrio. Preparations of the alkaline extracts (cholera allergen) obtained were standard by chemical composition, they were characterized by a high protein content (up to 77%) and were practically nontoxic. These preparations can be used as a bacterial allergen for the experimental investigations.

Allergens↗