Silatrane-Sulfonamide Hybrids as Promising Antibacterial Agents.

At the A. E. Favorsky Irkutsk Institute of Chemistry, a series of silatrane-sulfonamide hybrids 1a-d and 2a-d was synthesized. The antibacterial activity of 1a, 1b, 1d, 2a, and 2b against test strains of bacteria Yersinia pestis EV NIIEG, Yersinia enterocolitica 628/1, Listeria monocytogenes 766, and Starhylococcus aureus ATCC 6538-P (FDA 209-Р) was evaluated. The minimum inhibitory concentration for silatrane-sulfonamide hybrids was 100-200 mg/liter. Silatrane-sulfonamide hybrid 1d was the most active against all tested strains: minimum inhibitory concentration 100 mg/liter. Exposure to silatrane-sulfonamide hybrids in a doses of 100-200 mg/liter inhibited culture growth by 50-75%.

[Phagocytic functional and metabolic activities in the interaction with F. tularensis subspecies of various virulence].

There is evidence that the facultatively intracellular pathogen affects the functional capacity of phagocytes, which is associated with their bactericidal against a tularemic microbe with varying phenotypic properties. The tularemic microbe of the subspecies Francisella subsp. tularensis and F. tularensis subsp. mediaasiatica is shown to influence the phagocytic capacity of immunocompetent cells, resulting in incomplete phagocytosis. This is corroborated by the lower functional activity of neutrophils and macrophages in the interaction with tularemic microbe of the subspecies tularensis and mediaasiatica to a greater extent than in that with the representatives of other studied F. tularensis subspecies. The low content of cationic protein and the suppressed activity of NO-synthase may be associated with the loss of activity of the enzyme and cationic protein during phagocytosis of the tularemic microbe. The findings are of prognostic value in characterizing the severity of a pathological process caused by F. tularensis and in designing diagnostic and prophylactic agents.

[Comparative study of immunomodulating effects of natural experimental preparations on phagocytosis of Yersinia pseudotuberculosis]. / Sravnitel'noe izuchenie immunokorregiruiushchikh svoistv éksperimental'nykh preparatov prirodnogo proiskhozhdeniia pri fagotsitoze Yersinia pseudotuberculosis.

To correct defects of the body's phagocytic system, the authors used experimental agents, such as vital activity products of plant cells, which were obtained by biotechnology. These included arabinogalactan, syringin, K-212, and DFEGP. The study agents activate the oxidative metabolism of macrophages, the production of active forms of oxygen, and thus enhance its bactericidal effect against Yersinia pseudotuberculosis. Syringin and arabinogalactan produce a more pronounced stimulating macrophageal effect in Yersinia pseudotuberculosis phagocytosis than do K-212 and DFEGP. The findings indicate that further studies of the effects of these tested and other agents on humoral and cellular immunity are required.

[Characteristics of phagocytosis of Yersinia pseudotuberculosis with various sets of plasmids]. / Osobennosti fagotsitoza Yersinia pseudotuberculosis s raznym naborom plazmid.

The study used the selected aplasmid strain of Y. Pseudotuberculosis 53 and I-716, which contains plasmids that have molecular weights of 48 and 82 mD, and I-727 that has only virulence plasmid pYV48. The study has indicated that the fact that Yersinias have pVM82 and pYV48 enhances their resistance to phagocytosis. The Y. pseudotuberculosis strains carrying these plasmids suppress the responsiveness of phagocytes, inhibit an "oxidative explosion", lower the activities of superoxide dismutase and myeloperoxidase, thus suppressing their bactericidal capacity.