Vol 94, No 6 (2017)

Aim. Chracteristic of number and distribution of mosquitoes Ae. aegypti and Ae. albopictus in the Republic of Abkhazia and a risk assessment of virus Zika spread. Materials and methods. The accounting of mosquitoes number was made by the method «on the observer» in 20 minutes at the 70 nature landscapes points in april-oktober 2016. Results. The Black sea coast of the Republic of Abkhazia has favorable ecological conditions for the mosquitoes ingrowth of Ae. aegypti and Ae. albopictus. At 2016 the mosquitoes Ae. albopictus having vector competence to spread a Zika virus, has been revealed in the open stations in the territory from Ochamchirsky district to border with the Russian Federation. Their number is correlated with the air temperature in the region. The control of efficiency of the insecticidal works showed that in the open stations Ae. albopictus were not found within 3 - 7 days after the disinsection actions. However, their number of recovered as a result of settling from nearby natural biotopes. Conclusion. The risk of local Zika virus transmission has estimated as a low. Considering the gravity of the disease caused by the Zika virus carrying out a wider complex of the control methods of the mosquitoes number in areas of their dwelling, especially on the epidemiologically significant objects is necessary. The most effective of the population protection action is riddance of the reproduction mosquitoes places and sanitation of territory.

Aim. Study of the effect of antimicrobial peptides (AMP) on the sensitivity of the conditional pathogenic of bacteria to the action of antagonistic active of representatives mutualistically microflora. Materials and methods. The study used peptides from platelets of chicken obtained by the method of reversed-phase high-performance liquid chromatography in stepwise and linear gradients of increasing concentrations of organic solvent. The effect of AMP on the sensitivity of microorganisms to antagonistic active substances of the dominant bacteria of the genus Lactobacillus, and Enterococcus were investigated in a joint incubation. Antagonistic activity of bacteria studied the gup method. Results. Shown an increased expression of antagonistic activity of indigenous microflora in relation to associative microflora after concubinage with a peptide fractions from platelets of chicken. Conclusion. The obtained results allow to assume the existence of new mechanisms of formation of the colonization resistance of the biotope.

Aim. Norovirus infection (NVI) epidemiological characteristics evaluation in Moscow at municipal and district levels. Materials and methods. A retrospective analysis of NVI incidence rate was conducted according to the 2009 - 2016 state statistical reporting forms data. Results. In 2009 - 2016 NVI incidence rate has a trend to increase in Moscow, either at municipal and district levels. NVI cases were registered among children mostly (78% in the SEAD of Moscow, 80% in Moscow and 81% in Russia), at the same time adults proportion of NVI incidence rate increased significantly (up to 42,7% in Moscow and 13,9% in the Russian Federation) by 2016. The morbidity dynamics in different child population age groups was effected by the outbreaks cases. Totally in 2011 - 2016 33 outbreaks were registered in Moscow (24,3% from all acute diarrheal infection outbreaks in Moscow for the same period), where 64,3% with nonpercutaneous channel of infection and 35,7% alimentary. Outbreaks were more often recorded in children’s organized collectivity (69,7%). Conclusion. Nowadays in Moscow there is an NVI incidence increase trend is evidenced, with an increase of the adult population proportion in morbidity structure. At this stage, main contribution to group morbidity was made by children 7 - 14 and 15 - 17 years old. One of the reasons for the NVI incidence rate growth in Moscow (2016) could possibly be the lack of effective prevention measures. Actually, specific NVI diagnostics provided only in outbreaks, due to the lack of routine diagnostic tools. The main reason for the NVI group morbidity effective disease area formation is still sanitary and anti-epidemic regime violation at sites and facilities.

Aim. To characterize pool of Crohn’s disease-associated E.coli isolated from patients with Crohn’s disease. Materials and methods. 28 clinical stains were selected. Clinical isolates, as well as control samples, were tested for their possible belonging to a certain phylogenetic group, the ability to adhere and invade on the model of a monolayer of CaCo2 epithelial cells, the ability to form biofilms and their mobility. Results. We have shown that E.coli, isolated from a different biomaterial, belonged to different phylogenetic groups and differed in their ability to form biofilms. Adhesive-invasive E.coli were found mainly in the material of biopsy of the intestinal mucosa of patients with Crohn’s disease. Conclusion. There are reasons to suppose that adhesive-invasive E.coli formed at the junction of ecological niches of the lumen and the intestinal wall.

Aim. In this study we aimed to design the universal genetic construction expressing the light and heavy chains of a chimeric antibody, to develop methodological approaches for the production of chimeric antibodies with defined specificity using the monoclonal antibodies to diphtheria toxin (DT) DT-17 in the CHO cells as an example and to evaluate their immunochemical and effector properties. Materials and methods. Variable region genes of the light and heavy chains of mouse antibodies DT-17 to diphtheria toxin were obtained by PCR method and cloned into pCI-neo plasmid vector. The S V DT -17neo «supervector» containing the genes of a chimeric antibody was constructed by using of genetic engineering techniques. CHO cells were transfected with «supervector» and a highly productive clone secreting chimeric antibodies to DT were collected. Immunochemical methods were used to evaluate antibody activity, and affinity chromatography was used to prepare preparative amounts of the antibodies. Results. U ni versal vectors pLK DT -17 and pHG DT-17 containing light and heavy chain genes of the chimeric antibodies DT -17 to DT were constructed. The variable and constant region genes were flanked by endonuclease restriction sites, which allows to change the specificity of the antibodies. In the future it will make possible to study the modifications of the class and species specificity of the chimeric immunoglobulins. When the CHO cell culture was transfected with the designed vectors, the accumulation of antibodies to DT in the culture medium was detected. The yield of purified DT-17 chimeric antibodies was 4 mg per 1 liter of culture medium. The minimum concentration of chimeric antibodies necessary for DT neutralization in the CHO cells was 30 pg/mL. Conclusion. Universal plasmids encoding the synthesis of light and heavy chains of chimeric DT -17 antibody have been designed. On the basis of these vectors, a «supervector» and a highly productive clone secreting specific antibodies that had neutralizing activity against DT were obtained.

Aim. The development of the hepatitis E virus (HEV) genotype 1 recombinant capsid protein. Materials and methods. Escherichia coli strains, plasmid vectors, serological and clinical samples, ELISA reagent kits, molecular biological, bioinformatic, biotechnological, biochemical and serological methods. Results. Using HEV genotype 1 DNA copy of subgenomic virus RNA we made E.coli strains producing recombinabt capsid protein, containing C-terminal fragment of ORF2 protein fused to E.coli beta-galactosidase. Recombinant protein ORF2 had been isolated from the inclusion bodies of the E.coli biomass and purified by size exclusion chromatography. By Western blotting it had been shown specific interaction of the recombinant polypeptide with anti-HEV IgG from pool of positive sera. Antigenic specificity of the recombinant polypeptide had been confirmed by enzyme-linked immunosorbent assay with sera of hepatitis E patients and reference groups: healthy donors, patients with hepatitis А, В, C, infectious mononucleosis and cytomegalovirus infection, HIV-infected patients. Conclusion. HEV genotype 1 ORF2 recombinant antigen had been developed, and its possible use in diagnostic tests had been experimentally shown.

Aim. To estimate the dynamics changes in the population structure of the tuberculosis (ТВ) pathogen in the Irkutsk region by comparison of genotypes of M. tuberculosis from patients of different age groups. Materials and methods. 588 epidemiologically unrelated strains of M. tuberculosis isolates from 567 ТВ patients were characterized using 24-locus MIRU-VNTR typing. 160 strains belonged to patients of different age groups. 59 strains were isolated from the «young» people with ТВ who were bom after 1990 and 101 isolates from people who were born before 1955. Results. Two-thirds of the samples (427/567) were genotype Beijing with the dominance of two subtypes belonging to the modem epidemic clonal complexes CC1 and CC2. The high level of clustering profiles of CC1 and CC2 genotype Beijing in «older» and «young» patients in the Irkutsk region indicates the presence and active transmission of epidemic CC1 and CC2 subtypes over the past fifty years.

Presently Africa is one of the most affected regions of the world as regards cholera. More than 55 000 people are infected every year. The review contains the data on comparative assessment of epidemic manifestations associated with the current pandemic, caused by Vibrio cholerae biovar El Tor, and the preceding six pandemics, the agent of which was cholera vibrios of classical biovar. Studied have been the factors of large-scale cholera dissemination in Africa in the modern period and problems of its prophylaxis.