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V S Zueva

Publications and source records attributed to V S Zueva.

At least 19 recordsLinked to original sources
PubMed1992

[Phage-mediated conjugative transfer of plasmids in Staphylococcus aureus].

It was shown possible to transfer nonconjugative plasmids during joint cultivation of the donor and recipient cells by transduction and phage-mediated conjugation. In the latter case it was necessary that the phage in the medium was free and the prophage was present in the recipient cells. Differences in the regularities of the transfer of the nonconjugative plasmids mobilized by the conjugative plasmid or phage were observed.

Calcium Chloride↗
PubMed1991

A new approach to establishing the set of phages for typing methicillin-resistant Staphylococcus aureus.

A new approach to using experimental phages for typing methicillin-resistant S. aureus (MRSA) non-sensitive to the phages of International Basic Set (IBS) is described. The collection Includes phage 85, modified on a culture of MRSA, and 5 phages induced from MRSA strains isolated in clinics of Moscow in 1975-76. Firstly, the modified phage selects cultures according to the specific character of its restriction-modification system, then the induced phages differentiate the selected strains into 5 groups (1, 2, 3, 4, 5) based on the specificity of the prophages they contain. Group 1 strains can further be differentiated into 5 subgroups (A, B, C, D, E) by additional phages. Forty-one MRSA strains isolated in 1987-90 in various hospitals of Moscow showing no sensitivity to IBS phages, were lysed by the modified phage, 15 of them belonging to Group 2 and isolated in the traumatological hospital, 26 belonging to Group 1 and were circulating in the burn center. Twenty-three strains of Group 1 appertain to subgroup 1B and were isolated over a 4-year period from the burned surface of patients and from the throat of a medical staff carrier.

Bacteriophage Typing↗
PubMed1991

Lysogeny of methicillin-resistant Staphylococcus aureus and the role of prophages in transfer of conjugative and non-conjugative plasmids.

The lysogenicity of 49 strains of methicillin-resistant S. aureus (MRSA) isolated in Moscow clinics in the 1970s and '80s was studied by the method of mitomycin C induction. It was found that one strain had phage of serogroup B, 33 strains had serogroup F phages and 15 strains had phages of both serogroups. In the course of genetic crossing on nitrocellulose filters it was demonstrated that serogroups B and F prophages contained in recipient cells 1) increase the frequency of transfer of conjugative plasmid pG873 and 2) mobilize transfer of non-conjugative plasmids pE994 and rms7.

Conjugation, Genetic↗
PubMed1991

[The effect of leukinferon on the activity of phagocytosing cells in human salmonellosis].

The functional activity of phagocytic cells in 52 salmonellosis patients was studied with regard to the following characteristics: percent share of phagocytosis, phagocytic index, nitro blue tetrazolium test results, digestive activity. In patients with the unfavorable course of salmonellosis (the formation of carrier state) disturbances in the bactericidal activity of neutrophils and monocytes were established. For 32 patients leukinferon was included in the complex of etiotropic and pathogenetic treatment. The preparation was introduced in 3 intramuscular injections of 10,000 I. U. at intervals of 48 hours (the course of treatment); 10 days after the last injection this course was repeated. The use of leukinferon restored the normal functioning of phagocytes and the number of T-lymphocytes.

Adolescent↗
PubMed1991

[Differentiation of methicillin-resistant strains of Staphylococcus aureus by prophage specificity].

By inducing with mitomycin C the following phages were isolated from all the tested 32 methicillin resistant strains of S. aureus: the serogroup B phage was isolated from 2 strains, the serogroup B and F phages were isolated from 5 strains and the serogroup F phage was isolated from 25 strains. The phages were divided into 5 groups by the antiphage immunity. In group 1 of the phages 4 additional phages were specified. By the specificity of the prophages in the cultures all the strains were divided into 5 groups. Group 1 of the cultures was divided into 5 subgroups (A, B, C, D and E).

Bacteriophage Typing↗
PubMed1991

[Effect of prophages on transfer frequency of conjugative plasmid G 873].

Transfer of the conjugative plasmid G873 on filters and mixed cultivation of the donor and recipient cells in liquid media is described. In the both systems the use of the lysogenic recipient cells (phages of serogroups B and F) in the crossings increased mor than 100-fold the frequency of plasmid transfer. The conjugative transfer of the plasmid in the mixed cultivation system was proved. The conjugative transfer required the presence (while not obligatory) of calcium chloride and was restricted by the serum factors.

Animals↗
PubMed1990

[Clinical and laboratory effect of leukinferon in purulent infections].

Clinical trials of human leukocytic alpha-interferon for injections, leukinferon were performed in 51 patients with different forms of surgical purulent infections. It was shown that leukinferon lowered the terms of normalization of body's temperature, leukocytosis, respiratory neutrophilic outbreak and levels of active T-lymphocytes. The same was observed when leukinferon was used prophylactically in cardiosurgical patients. The effect of leukinferon depended on the level of radical operations on primary purulent foci and severity of the patient's state. Leukinferon had immunomodulatory properties and mainly influenced the system of neutrophilic phagocytes. The action was lymphocyte-mediated. The rapid effect of leukinferon makes it necessary to recommend it for treatment of patients with purulent infections as an agent of urgent immunomodulation.

Adjuvants, Immunologic↗
PubMed1989

Association between phage DNA injection and generation of the protonmotive force in Staphylococcus aureus.

Suppression of protonmotive force generators in staphylococci lead to a loss of phage infection efficiency. KCN inhibited phage infection by 49.5-53.5%; DCCD by 51.0-61.4%; CCCP by 59.2-68.8%. Suppression tock place at the stage of phage DNA transport. Valinomycin in concentration of 0.5 microM evoked dissipation of the membrane potential, nigericin caused a reduction of the gradient pH in the staphylococci membrane at a concentration of 12.0 microM. Individually, these antibiotics did not have an essential influence on the efficiency of phage infection but when combined, a maximum inhibition of phage infection (64.5%) occurred at the stage of introducing phage DNA into the bacterial cell implicating the participation of the membrane potential and pH gradient in the transportation of phage nucleic acid to the staphylococcal cell.

Biological Transport, Active↗
PubMed1988

[Changes in the bactericidal activity of macrophages from mice with various degrees of resistance to Salmonella typhimurium infection as affected by interferon].

The bactericidal activity of mouse macrophages with different sensitivity to Salmonella infection has been studied. The sensitivity of BALB/c mice to S. typhimurium infection is associated with the low bactericidal activity of their macrophages. The introduction of interferon stimulates the bactericidal activity of macrophages sensitive to Salmonella infection of mice, which sharply enhances the resistance of the animals to this infection.

Animals↗
PubMed1988

[Interferon activation of the production of a factor increasing the bactericidal properties of mouse macrophages].

It has been established that the administration of homologous interferon to mice activates the production by splenocytes of a factor increasing the bactericidal properties of macrophages in the peritoneal exudate. The activation effect was dose-dependent. The maximum production was noted on day 3 after the injection of interferon, type I, or its inducers. Cell-producers of the factor are mainly lymphocytes.

Animals↗
PubMed1987

[Effect of the synthetic preparation B 58 on the activity of natural killer and cytostatic cells of the mouse spleen].

The effect of the in vivo treatment with synthetic interferon inducer B-58 on natural killer (NK) and cytostatic cell activity was studied in CBA and A/Sn mice. A marked increase in NK cell activity against target cells YAC-1 was observed in the spleen of CBA mice within 4 days after treatment. On the other hand, NK activity in A/Sn mice was not affected by B-58. However, B-58 was shown to enhance cytostatic cell activity both in CBA and A/Sn mice, when tested against target cells P 815.

Animals↗