[The possibility of creating a vaccinal strain of Brucella abortus 19-BA with multiple antibiotic resistance]. / O vozmozhnosti sozdaniia vaktsinnogo shtamma Brucella abortus 19-BA s mnozhestvennoi ustoichivost'iu k antibiotikam.

The possibility of preparing B. abortus vaccine strain 19-BA with multiresistance to antibiotics was shown. The strain was obtained by the spontaneous induction of resistance to rifampicin with the subsequent transformation of nonconjugative hybrid plasmid pOVI which, in addition to rifampicin resistance, governed the resistance of brucellae to tetracycline, doxycycline, ampicillin, and streptomycin. Experiments on guinea pigs demonstrated the immunization with both multiresistant vaccine strain GSA1 and B. abortus initial vaccine strain 19-BA.

[Biological and physicochemical properties of Brucella isolated from murine rodents]. / Izuchenie biologicheskikh i fiziko-khimicheskikh svoistv brutsell, vydelennykh ot myshevidnykh gryzunov.

The comparative study of the chemical composition, immunobiological activity and some physico-chemical properties of lipopolysaccharide (endotoxin) of Brucella cultures isolated from myomorph rodents in the North Caucasus has been carried out. Lipopolysaccharide obtained from these cultures has been found to be most similar to B. suis lipopolysaccharide. The authors suggest that the strains isolated from myomorph rodents outside the foci of brucellosis affecting livestock should be regarded as a separate biotype of B. suis.

[Cell structure and the pathogenicity of Brucella at different stages of L transformation]. / Struktura kletki i patogennost' brutsell na raznykh étapakh L-transformatsii.

On the basis of changes in the biological properties and morphology of Br. abortus culture under the action of penicillin 3 stages of L-transformation in Brucella were determined. The prevalence of first bacilliform and then typical L-cells and rapid reversion hampering the determination of virulence were characteristic of the initial stage (passages 1-4). Typical L-cells with the wrinkled surface, deep depressions and holes as well as a decrease in virulence and slight pathomorphological changes in the organs of the infected animals were characteristics of the intermediate stage (passages 5-10). Typical L-cells and amorphous masses, a further decrease in virulence, pathomorphological changes of toxic character (only after the injection of L-culture in large doses) were characteristic of the late stage (from passage 11 and further on). At all stages of L-transformation Brucella cultures showed a high reproductive capacity, binary division, the formation of elementary bodies by budding both inside and on the surface of L-cells.

On the pathogenicity of nonstable Brucella L-forms and their revertants.

The pathogenicity of B. abortus 870 L-forms obtained by long-term passaging of virulent culture on media with penicillin and of revertants obtained in vitro and in vivo was studied. L-form cultures stimulated only a mild response of the reticulo-endothelial system of the animal organism, at the same time displaying a certain level of toxicity. In vitro revertants approximated to L-forms, while in vivo revertants stood closer to the initial virulent culture, as regards pathogenicity. This seems to be evidence of a potential danger of brucella L-forms for the human and animal organisms.

[Lysozyme concentration in the loose connective tissue of animals with different species sensitivity to brucellosis]. / Soderzhanie lizotsima v rykhloi soedinitel'noi tkani u zhivotnykh s razlichnoi vidovoi chuvstvitel'nost'iu k brutselleznoi infektsii.

Lysozyme content was determined in the subcutaneous cellular tissue of guinea pigs and albino rats differing by species resistance to brucella infection. Experiments were conducted on intact animals and those inoculated subcutaneously with live Br. abortus 19-BA vaccine. Connective tissue was taken from the site of the vaccine administration and from the contralateral side (control). Observations showed connective tissue of the animals highly sensitive to brucella infection to be exceedingly poor in this enzyme; as to connective tissue of albino rats with low sensitivity--it contained high amount of this enzyme. Lysozyme content increased considerably in the animals belonging to both species in the inflammatory focus developing at the site of the vaccine inoculation.

[Pathogenicity of the Shigella isolated from wild and game animals of the Far North of the USSR]. / O patogennosti brutsell, vydelennykh ot dikikh i promyslovykh zhivotnykh Krainego Svera SSSR.

Experiments were conducted on guinea pigs. A study was made of the pathogenicity of brucellae culture isolated from various wild and Game animals of the extreme North of the USSR (wolf, polar fox, ermine, glutton). The majority of the cultures under study proved to be highly pathogenic. Observations carried out led to the conclusion that brucella cultures circulating between the wild and domestic reindeers and migrating to other species of animals presented definite danger to the health of man.

[Character of the immune response in guinea pigs following immunization with brucellosis protective antigen]. / Kharakter immunogo otveta u morskikh svinok pri immunizatsii brutselleznym protektivnym antigenom

In studying guinea pigs immunized with brucella protective antigen and the immunological response in them it was found that the antigen could be determined for 30 days by the method of fluorescent antibodies in the cells of the lymph nodes and the spleen following its intravenous injection. The optimal immunizing dose was 0.6 mg; in difference from a dose of 2 mg it produced an earlier and a more pronounced humoral effect. The phagocytic activity of the peritoneal macrophages of guinea pigs immunized with low doses was much more intensive than of those immunized with high doses of the antigen. Brucella protective antigen in a dose of 2 mg produced a disturbance of the carbohydrate metabolism in phagocytes, this influencing negatively their phagocytic function.

[Role of clasmatosis of the phagocytes in immunogenesis]. / O roli klazmatoza fagotsitov v immunogeneze

With the aid of cytological and cytochemical studies it was shown that clasmatosis of phagocytes (micro- and macrophages) was primarily characteristic of active phagocytising cells, and not of dying cells as considered formerly. Experiements were conducted on guinea pigs in the course of vaccinal and infectious processes in brucellosis. As noted, clasmatosis of phagocytes known in intact animals was considerably enhanced during vaccinal and infectious processes. Pieces of cytoplasm separating from phagocytes were full of acid phosphatase, brucella antigen; fragments of macrophage cytoplasm in addition contained RNA. There are reasons to suppose that with the aid of clasmocytosis of phagocytes became intensified and the antigenic information spread rapidly in the animal organism.