[Investigation of molecular mechanisms of aminoglycoside resistance in Salmonella].

The spread of aminoglycoside resistance phenotype and respective genetic resistance determinants was evaluated in 243 Salmonella strains isolated within 1948-2010 and stored in the Culture Collection of the Russian State Research Institute for Control, Standardization and Certification of Veterinary Preparations (Moscow). The Salmonella strains showed resistance to streptomycin and gentamicin in 3.7% (n = 9) and 0.8% (n = 2) of the isolates respectively. Intermediate resistance to streptomycin was recorded in 9.9% (n = 24) of the isolates. To detect the genes responsible for the aminoglycoside resistance, primers for aadA1, aadA2, aadB, aphA1, aphA3, sat, strA, strB, aphA, aacC, rmtB, armA and rpsL genes amplification and sequencing were designed. The strains with lower susceptibility to streptomycin harbored aadA1, aadA2, strA, strB resistance genes encoding enzymes for aminoglicoside modification and rpsL mutant allele (K42N, G91D). Genetic mechanisms able to explain the gentamicin resistance development were not detected. Some strains carried genetic markers of streptomycine resistance but had no clinically sufficient resistance to it. In this regard, genetic testing is essential for prevention of drug resistance spreading due to horizontal transfer of genes in microbial population.

[Design of experimental approaches on the base of standard proteins for testing blood biopreparations and immunoperoxidase conjugates specific to human and animal immunoglobulines G].

Using standard forms of immunoglobulin (Ig) G and albumin, we have studied electrophoretic and chromatographic profiles of samples of pharmaceutical blood biopreparation batches. The usability of standard proteins was also demonstrated by testing analytical characteristics of immunoperoxidase conjugates specific to human and animal IgG (anti-IgG IPC). In particular, we suggest an additional estimation of analytical characteristics of anti-IgG IPC by the enzyme reaction kinetics with the standard dilution which is calculated by the direct enzyme-liked immunoassay on the homologous IgG-antigen.

Biomonitoring of selected persistent organic pollutants (PCDD/Fs, PCBs and PBDEs) in Finnish and Russian terrestrial and aquatic animal species.

BACKGROUND: The Finnish and Russian animal species (semi-domesticated reindeer, Finnish wild moose, Baltic grey seal and Baltic herring) samples were biomonitored in terrestrial and aquatic environments for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenylethers (PBDEs). RESULTS: Grey seal (Halichoerus grypus) was clearly the most contaminated species. The mean PBDE concentration in grey seal was 115 ng/g fat, and the highest WHO-PCDD/F-PCB-TEQ (toxic equivalent set by WHO) was 327 pg/g fat. In Finnish, reindeer WHO-PCDD/F-TEQ varied from 0.92 pg/g fat in muscle to 90.8 pg/g fat in liver. WHO-PCDD/F-TEQ in moose liver samples was in the range of 0.7-4.26 pg/g fat, and WHO-PCB-TEQ in the range of 0.42-3.34 pg/g fat. Overall moose had clearly lower PCDD/F and DL-PCB concentrations in their liver than reindeer. CONCLUSIONS: Terrestrial animals generally had low POP concentrations, but in reindeer liver dioxin levels were quite high. All Finnish and Russian reindeer liver samples exceeded the EU maximum level [8] for PCDD/Fs (10 pg/g fat), which is currently set for bovine animals.

[Phylogenetic analysis of swine fever virus strains]. / Filogeneticheskii analiz shtammov virusa chumy plotoiadnykh.

Amplification of H-gene fragment in combination with cDNA nucleotide sequencing can be used for indication and strain differentiation of classical swine fever virus.

Comparative study of the immunobiological properties of live brucellosis vaccines.

Findings from the comparative study of the immunobiological properties of live brucellosis vaccines in guinea pigs are presented in the article. Vaccines from strains Brucella abortus 19 (U.S.) and 82 (Russia), in the S and SR forms, respectively, exhibited the highest and most pronounced immunological efficacy, while vaccines from strains B. abortus 82-PS (in the RS form) and B. abortus RB-51 and 75/79-AB (in the R forms) exhibited the lowest. The live vaccine from strain B. abortus 82, together with a high immunological activity, possesses inagglutinogenic properties. The great advantage of this vaccine over the vaccine from strain B. abortus 19 is that after its use in animals the problem of the differential diagnosis of brucellosis becomes much simpler. The live vaccine from strain B. abortus 82 was adopted in veterinary practice in the Russian Federation; it is widely used for the targeted prevention of bovine brucellosis, but can also be used successfully for wild animals such as bison, deer, elk, and others.