Vol 23, No 3 (2016)

Polychlorinated biphenyls (PCB) are ones of most widespread toxic xenobiotics being resistant to environmental degradation. Recovery of natural ecosystems from PCB contamination is primarily related to activity of microorganisms capable of degrading these compounds. In order to study the bacterial communities of degraders from the PCB-contaminated grounds from the area of the JSC «Middle-Volga Chemical Plant» (the City of Chapaevsk, Samara Region), there was evaluated a number of bacteria-degraders in the grounds; the taxonomic composition of these communities was determined and most efficient bacterial associations degrading the PCB were selected. The ground samples taken from this enterprise territory have shown that the PCB concentration varied within 0.21-1.07 mg/kg. The amount of bacteria-degraders of biphenyl/PCB in the grounds under study was estimated as 4.0x106 - 1.5x107. Meanwhile, with the increase of the PCB concentration in the grounds, there was detected elevated number of bacteria-degraders. It was determined that bacterial degraders were represented by genera Achromobacter, Pseudomonas, Arthrobacter, Microbacterium, Acinetobacter, Bacillus, and Rhodococcus. Bacterial associations of degraders were selected that effectively degraded the PCB commercial mixtures «Delor 103» and «Sovol». These bacterial associations may be used for development of new biotechnologies, for remediation of PCB-contaminated soils and grounds.

In the article, there have been presented the results of assessment of working conditions' impact on workers of a vessel metal hulls assembly shop of a machine building plant on levels of morbidity with temporal disability (MTD). The assessment of the working conditions has been made according to the results of the assessment of workplaces, the levels of MTD - on the ground of the longterm average annual indices for 2005-2014. The cause-and-effect relations between the working conditions and the MTD levels have been established by means of a comparison of the working conditions' classes according to the results of the workplaces' assessment and the MTD levels characterizing the impact of harmful factors on the most vulnerable human body organs and systems. According to the study results, it has been established that the MTD levels of the respiratory viral infections, diseases of the respiratory organs, diseases of the locomotor system and connective tissue, diseases of the genitourinary system were statistically significantly connected with the effect of low air temperatures, high concentrations of harmful chemical substances in the working zone air, high levels of local vibration and high labor burden.

The article is devoted to the study of biological activity, including pathogenicity factors, of marine bacteria isolated from water in areas with different anthropogenic load, both coastal zones with high levels of different pollutants and pure zones with no human impact. To maintain the experimental integrity, we excluded Enterobacteriaceae from the obtained collection of marine microorganisms. Then we worked with the rest of the isolates for detection of their hydrolytic activity toward organic substrates, antibiotic resistance and such pathogenicity factors as: cytotoxicity, hemolytic activity, plasma coagulase and hyaluronidase activities. Comparative studies of hydrolytic activity in microorganisms isolated from sea water with different anthropogenic load have not revealed any differences in these indicators. However, the strains isolated from water areas with great impact of industrial, domestic and river drains, were highly antibiotic-resistant, highly adhesive and cytotoxic compared to the strains isolated from pure sea water. It is assumed that pollution of marine environment results in manifestation of aggressive properties of microorganisms, as a response to impact of stress factors that is both of general biological, ecological and epidemiological significance.

A new approach to the problem of significant youthification of arterial hypertension and its fast progression in non-indigenous populations of the polar and arctic regions has been presented. The hypertension progression in high latitudes is combined with influence of climate change biological stressful pace in the Arctic area and influence of adverse space, geophysical, weather, chronobiologi-cal factors. Research scientists of the Russian polar and arctic regions have identified a number of leading elements of the northern climatic-geographic chronic stress which make the main contribution to formation and progression of hypertension in the North. The most characteristic manifestations of climatic-geographic stress in uncomfortable and extreme regions of the North and Siberia are reactions of the central nervous and endocrine systems, metabolic changes and development of "oxidative stress". In addition to these manifestations the polisindromatic climatic stress may include: deficit of detoxification processes and barrier organs, northern metabolic type disorders, northern tissue hypoxia, immune deficiency, blood hypercoagulation, multiple endocrine disorders, regenerative and plastic failure, violation of electromagnetic homeostasis, functional dissymmetry of interhemispheric relations, desynchronosis, emotional stress, meteopathies. Obviously, creation of advanced innovative preventive and therapeutic technologies to reduce spread of hypertension among population in the polar and arctic regions require active study of the northern stress mechanisms' role in progression of this severe cardiovascular pathology.

This paper presents an approach to implementing institution-wide surveillance of healthcare-associated infections by means of regular point-prevalence surveys. We explain the methods of data collection and statistical analysis in details. Healthcare-associated infections are defined as localized or systemic conditions which was not present on admission or within the first 48 hour of hospital stay (or 30 days for surgical site infections). The prevalence of different categories of healthcare-associated infections varies in different hospitals that can be explained by variations in hospital stocks, types of medical units, treatment, age of patients and others. According to different published sources, the incidence of healthcare-associated infections in Russia exceeds the official data. An inconstancy in published results probably indicates under-registration of healthcare-associated infections and demonstrates a need for alternative surveillance measures to provide a basis to enhance the practice of infection control. Repeated prevalence surveys are known as simple surveillance options, which are efficiently used in the European countries. This method allows to obtain data on prevalence of different categories of healthcare-associated infections and factors associated with occurrence of infections in different hospital units. The results allows to identify areas requiring improvement in the hospital and develop specific prevention strategy for every hospital unit.