[The efficacy and outlook for the study of live vaccines for the prevention of melioidosis]. / Effektivnost' i perspektivy issledovaniia zhivykh vaktsin dlia profilaktiki melioidoza.

The effect of immunization with Burkholderia pseudomallei, (Pur- and Ts), heterologous vaccines and the recombinant culture of Francisella tularensis RM2, carrying a plasmid with fragments of B. pseudomallei chromosome, was studied on four species of experimental animals, essentially differing by their sensitivity to melioidosis. B. pseudomallei mutants formed the statistically significant level of protection in subcutaneously challenged animals, moderately sensitive to melioidosis, but were not effective when tested, under the same conditions, in animals, highly sensitive to melioidosis. The effect produced by the experimental vaccines under study in animals of all species, subjected to aerogenic challenge, was leveled. The study showed good prospects for the use of tularemia vaccine with a view to create heterologous immunity to melioidosis and the possibility of its use as the basis of bivalent gene engineering vaccine.

[The outlook for the development of live vaccines for the prevention of melioidosis]. / Perspektivy razrabotki zhivykh vaktsin dlia profilaktiki melioidoza.

The effectiveness of immunization with Burkholderia pseudomallei attenuated strains (Pur and Ts), heterologous vaccines and the recombinant culture of Francisella tularensis RM2 carrying a plasmid with fragments of B. pseudomallei chromosome was studied in four species of experimental animals, essentially differing in their sensitivity to melioidosis. The most immunogenic B. pseudomallei mutants, introduced subcutaneously, created a statistically significant level of protection in animals, moderately sensitive to melioidosis, but proved to be ineffective in highly sensitive animal models when tested under the same conditions. In aerogenic infection the effectiveness of the experimental vaccines under study in all species of the animals was on the same level. The study showed good prospects of using tularemia vaccine for inducing heterologous immunity to melioidosis, as well as the possibility of its use as the basis of a bivalent gene-engineering vaccine.

[The immunogenicity and heterogeneity of Pseudomonas pseudomallei surface antigen 8]. / Immunogennost' i geterogennost' poverkhnostnogo antigena 8 Pseudomonas pseudomallei.

Surface antigen 8, one of pathogenicity factors of P.pseudomallei and having an antiphagocytic action, contains glycoprotein with a mol. wt. of 200 kD and proteins with mol wt. of 25, 30 and 34 kD. According to its chemical structure, the carbohydrate part of antigen 8 is the homogeneous polymer of 6-d-D-mannoheptose, and its protein component is a collection of monomer proteins with mol. wt. of 12-120 kD. The consecutive fractionation of antigen 8 by gel and ion exchange chromatography has made it possible to isolate its individual fragments, differing by the collection of antigenic components, as well as by their antiphagocytic and protective activity. Experiments have shown that glycoprotein with a mol. wt. of 200 kD is an active immunosuppressive agent, while protein with a mol. wt. of 34 kD produces a pronounced immunogenic effect.

Structure of the polysaccharide chains of Pseudomonas pseudomallei lipopolysaccharides.

The pathogenic bacterium Pseudomonas pseudomallei strain 57576 produces two partially O-acetylated O-antigenic polysaccharides (PS-I and PS-II). Methylation analysis and 1H and 13C NMR spectroscopy, including NOE experiments, showed PS-I to have the structure [formula: see text] and PS-II to have the structure [formula: see text] where 6dmanHep is the unusual higher sugar 6-deoxy-D-manno-heptose. PS-II is produced also by P. pseudomallei strains 100 and 110, and PS-I and O-deacetylated PS-II by strain 97.

[Problems of resistance of the causative agent of melioidosis to antibiotics]. / Problemy rezistentnosti vozbuditelia melioidoza k antibiotikam.

It was shown that the pathogen causing melioidosis was highly resistant to antibiotics including beta-lactams. Antibiotic sensitive mutants of P. pseudomallei were isolated after mutagenesis induced by nitrosoguanidine. Permeability for 3H-tetracycline and tetracycline sensitivity of the mutant cells was respectively 3 and 20 times as high as those of the initial parent strain. Gas liquid chromatography revealed quantitative and qualitative changes in separate sugars of the lipopolysaccharide structure in antibiotic sensitive mutants as compared to the initial strain.

Incidence of renal artery stenosis in a population having cardiac catheterization.

Patients with renovascular hypertension comprise only a small percentage of those with hypertension. In our study 102 consecutive patients who had cardiac catheterization were screened at the time of the procedure for renal artery stenosis. Only 65 (64%) of the 102 patients were hypertensive, and 14 of the total population (13.7%) had renal artery stenosis. Of these 14 patients, only five had more than 50% narrowing of the arterial lumen. By renal vein renin determination, only four of the five patients with significant renal artery stenosis had lateralizing renins. The frequency of significant renovascular hypertension does not justify the routine search for this problem during catheterization procedures, though it may be worthwhile if the patients are hypertensive. This area deserves further evaluation.

[Nature of Pseudomonas pseudomallei antigens common to some species of microorganisms]. / K prirode antigenov Pseudomonas pseudomallei, obshchikh dlia nekotorykh vidov mikroorganizmov.

An antigen, common for the infective agents of glanders , tularemia, plague, pseudotuberculosis, cholera and brucellosis, has been obtained from the aqueous saline extract of P. pseudomallei by means of affinity chromatography on antibody sorbent. The isolated antigen has proved to be of a protein-polysaccharide-lipid nature, to have insignificant cathode mobility and to constitute a component of O-antigen. It has also been found to be antigenically related to the tissues of melioidosis-sensitive animals and localized in the surface structure of the bacterial cell.

[Membrane antigens of the agents of glanders and melioidosis]. / Antigeny membran vozbuditelei sapa i melioidoza.

Double immunodiffusion in gel test was used to determine the antigenic composition of the preparations of membranes isolated from the lysozyme spheroplasts of glanders (strain No. 10230) and melioidosis (strain No. C-141) causative agents. The membranes of these microbes proved to contain antigens of cell walls, lipopolysaccharides and the thermolabile membrane antigen proper. A study of antimembrane sera in the agglutination and immunofluorescence tests demonstrated a heterogeneity of the glanders and melioidosis strains under study by the membrane thermolabile antigen.

[Obtaining spheroplasts from the agents of glanders and melioidosis and separation of membrane structures from them]. / Poluchenie sferoplastov iz vozbuditelei sapa i melioidoza i vydelenie iz nikh membrannykh struktur.

Spheroplasts were obtained from the causative agents of glanders and melioidosis under the effect of lysozyme and antibiotics. In the capacity of an inducing agent lysozyme was effective in high concentration only (0.4%); preliminary washing and incubation in sucrose were necessary to obtain glanders spheroplasts. Of the antibiotics studied penicillin was more useful for obtaining melioidosis spheroplasts and ampicillin--for glanders spheroplasts. Membrane preparations were derived from the spheroplasts of glanders and melioidosis causative agents.

[Comparative characteristics of the ultrastructure of the causative agents of glanders and melioidosis]. / Sravnitel'naia kharakteristika ul'trastruktury vozbuditelei sapa i melioidoza

The authors examined the ultrastructure of the causative agents of glanders and melio idosis. It was revealed that the structure of their cell wall and of the cytoplasmic membrane was characteristic of Gram negative bacteria. The cytoplasm of both types of the causative agents showed the presence of ribosomes, membrane structure, nucleoid, and also osmiophilic and osmiophobic inclusions.