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V V Shevtsov

Publications and source records attributed to V V Shevtsov.

27 records · Page 2Linked to original sources
PubMedDate not supplied

[Activity of intracellular enzymes in Bacillus thuringiensis prospores and sporangia].

The activity of endocellular enzymes (alkaline phosphatase, protease, glucose dehydrogenase, aldolase, malate dehydrogenase, NADH dehydrogenase, NADH oxidase) was studied in isolated prospores and sporangia as well as in vegetative cells of Bacillus thuringiensis strains, one of which produced crystals and one did not. The activity of malate dehydrogenase and NADH dehydrogenase was high in prospores of the both strains at the fifth and sixth stages of spore formation. The strain which did not produce crystals differed from the parent strain by a higher aldolase activity at all of the growth stages and by an abrupt increase in the activity of hydrolytic enzymes in sporangia (in the cytoplasm of the parent cells).

Alkaline Phosphatase↗
PubMedDate not supplied

[Membrane-active properties of a preparation from a bacterial culture broth possessing autoregulation action].

The effect of a preparation obtained by butanol extraction of the culture fluid of B. cereus and Ps. carboxydoflava and previously termed an autoregulatory factor d1 on the respiration chain within intact bacterial cells and isolated membranes was investigated. In comparable concentrations this factor d1 inhibits the endogenous respiration of B. cereus and M. lysodeikticus as well as oxidase and dehydrogenase activities of isolated membranes from these bacteria and E. coli. The factor-induced decrease of the cell respiration rate is independent from disorders of the cell permeability osmotic barrier for respiration substrates. The factor d1 shows a higher effect at acidic pH values. It is concluded that the above preparation has membrane-active properties. It is also suggested that in the bacterial cell its target is the inner surface of the cytoplasmic membrane.

Bacillus cereus↗
PubMedDate not supplied

[Effect of temperature and aeration on Bacillus thuringiensis growth and sporulation].

The growth of Bacillus thuringiensis was studied as a function of temperature and aeration. The vegetative growth, the yield of viable spores and their thermoresistance did not depend, for all practical purposes, on the rate of aeration within the range of 25 to 60 mg O2 per litre per minute. A rise of temperature from 20 to 35 degrees C doubled the titre of spores and increased their thermoresistance. When the temperature of cultivation was increased to 40 degrees C, the process of spore formation was inhibited.

Aerobiosis↗
PubMedDate not supplied

[Resistance of resting cyst-like forms of Bacillus cereus to exposure to high temperature, ultraviolet rays and low-molecular alcohols].

The dormancy cyst-like forms of Bacillus cereus obtained under the action of an autoregulatory factor were shown to be more resistant to the action of such external factors of the medium as high temperatures, ultraviolet irradiation and low molecular weight alcohols comparing to the vegetative cells. Incubation at 80 degrees C for 15 min killed 98,5% vegetative cells and 86,5% of the dormancy refractile forms. U. V.--radiation treatment resulted in a loss of viability in 97% of the vegetative cells and in 75% of the refractile forms. Differences were also found in the resistance of the cyst-like forms and the vegetative cells to the action of ethanol, methanol and butanol. The resistance of the cyst-like forms of B. cereus to the action of the above damaging factors is consistent, in general, with the resistance of cysts, methylotrophic bacterial spores and other dormancy prokaryotic cells differing in the mode of their formation from endospores.

Alcohols↗
PubMedDate not supplied

[Effect of physicochemical factors on Bacillus thuringiensis sporulation].

Spore germination was studied in Bacillus thuringiensis subsp. galleriae. Optimal temperature regimes were selected for spore activation and initiation. The formation of spores and the rate of their subsequent germination were shown to depend on the composition of growth media in which the organism was cultivated. The paper describes changes in the fine structure of spores at different stages of their germination.

Bacillus thuringiensis↗
PubMedDate not supplied

[The efficacy of entomopathogenic bacilli against ancylostomide larvae--Nippostrongylus braziliensis Travassons, 1914].

Effects of seven bioinsecticides, containing Bacillus thuringiensis and B. sphaericus toxins, against N. braziliensis larvae were studied in vitro. Bitoxibacillin, astur-3, astur-4, gomelin, lepidocide, dendrobacillin, thuringin and sphaerix were found highly effective larvicides. Protein endotoxin was the principal component responsible for the larvicidal effect, the spores were of no importance.

Animals↗
PubMedDate not supplied

[Current aspects and prospects of the combined treatment of respiratory papillomatosis in children].

Treatment methods and outcomes have been analyzed for 313 children aged 9 months-14 years with respiratory papillomatosis (RP) admitted to ENT clinic in 1950-1995. Beginning from 1982 papillomas were removed by means of ultrasonic disintegration. A novel approach included extracorporeal detoxication and immunocorrection. 85% of patients responded to treatment with discrete plasmapheresis and T-activin. It is concluded that best treatment results were achieved in combination of conventional methods with advanced modalities such as extracorporeal detoxication and immunocorrection.

Adjuvants, Immunologic↗
PubMedDate not supplied

[Indicators of resistance to infection in children with respiratory papillomatosis].

The study was made of microbiological and immunological aspects of antiinfectious resistance (AIR) in children with respiratory papillomatosis (RP). At admission to hospital RP patients exhibited dysbacteriosis of the upper respiratory tract and colon. Immunological and microbiological response to the infection recurrences was adequate. Interrelated immunological and microbiological indices in RP objectively reflect the course of the pathological process and may be used in objective assessment of the disease and choice of its treatment.

Adolescent↗