Molecular Epidemiology of Hypervirulent K. pneumoniae and Problems of Health-Care Associated Infections.

The review describes virulence factors of hypervirulent K. pneumoniae (hvKp) including genes determining its virulence and discusses their role in the development of health-care associated infections. The contribution of individual virulence factors and their combination to the development of the hypervirulence and the prospects of using these factors as biomarkers and therapeutic targets are described. Virulence factors of hvKp and "classical" K. pneumoniae strains (cKp) with no hypervirulence genes were compared. The mechanisms of biofilm formation by hvKp and high incidence of its antibiotic resistance are of particular importance for in health care institutions. Therefore, the development of methods for hvKp identification allowing early prevention of severe hvKp infection and novel approaches to abrogate its spreading are new challenges for epidemiology, infection diseases, and critical care medicine. New technologies including bacteriological and molecular studies make it possible to develop innovative strategies to diagnose and treat infection caused by hvKp. These include monitoring of both genetic biomarkers of hvKp and resistance plasmid that carry of virulence genes and antibiotic resistance genes, creation of immunological agents for the prevention and therapy of hvKp (vaccines, monoclonal antibodies) as well as personalized hvKp-specific phage therapies and pharmaceuticals enhancing the effect of antibiotics. A variety of approaches can reliably prepare our medicine for a new challenge: spreading of life-threatening health-care associated infections caused by antibiotic-resistant hvKp strains.

[The study of tryptophan metabolite concentrations in blood serum and fecal extracts from obese children]. / Izuchenie soderzhaniia metabolitov obmena triptofana v syvorotke krovi i kalovykh ékstraktakh u detei s ozhireniem.

We found that changes in the concentrations of tryptophan metabolites in the blood serum and in the intestinal contents are one of the mechanisms for the formation of metabolic coupling in the system "macroorganism-intestinal microbiota", which undergoes significant changes in the development of obesity. Although blood kynurenine remained basically unchanged in obese children we found an increase in some of its serum metabolites: anthranilic, kynurenic and xanthurenic acids. It is noteworthy that in the analysis of fecal matter in obese children, revealed a 2-fold increase in the level of kynurenine while the concentration of kynurenine pathway metabolites corresponded to the level of the group of healthy children. This may indicate the metabolic activation of the microbiota associated with the intestinal mucosa. This is also supported by the absence of statistically significant differences in the concentration of indole in healthy children and in obese children in fecal analyses, and a significant increase in the concentration of indole-3-lactate and indole-3-acetate in the blood serum of obese children.

[Formation of biological films by microororganisms in food productions].

The aim of this review is to analyze the problem of biofilm formation by pathogenic bacteria in food enterprises and the risks associated with this phenomenon. The aspects of the formation of biofilms by pathogenic microorganisms at food industry enterprises have been considered from the point of view of the potential danger of infection and colonization of processing plants by biofilm-forming strains. Biofilms are the preferred form of bacteria existence. It is known that bacteria in a state of biofilm are protected from adverse environmental factors and antibacterial substances, they are often resistant to standard cleaning and disinfection procedures. The formation of biofilms on biotic and abiotic surfaces is a potential hazard, contributing to the constant circulation of pathogens in the conditions of food production and contamination of foods. The problem of biofilm formation is characteristic of all food enterprises.

Effect of Bacillus subtilis KATMIRA1933 and Bacillus amyloliquefaciens B-1895 on the productivity, reproductive aging, and physiological characteristics of hens and roosters.

The study aims at investigating the effect of preparations of two bacilli strains on laying hens and roosters. Preparations were based on the strains Bacillus subtilis KATMIRA1933 and Bacillus amyloliquefaciens B-1895. Several groups of roosters and hens received a preparation based on either strain, or a mixture of both, from the first day to the last day of poultry in production. These preparations improved egg production, quality of sperm production, quality/hatchery of eggs, and slowed down the reproductive aging of hens. These observations were confirmed by the mathematical model proposed herein. At the molecular level, the slowing down of aging was confirmed by a decrease in the amount of mitochondrial DNA damage. Monitoring the physiological parameters of the experimental and control groups of birds showed that live weight gain in all experimental groups was higher than in the control group, and the reproductive organs of hens were more developed. There was also an improvement in the biochemical parameters of blood, the quality of the sperm of roosters, the laying of laying hens, and the morphological and biochemical parameters of the eggs. One of the most significant results is an increase in egg fertilization and a decrease in embryo death during the first 7 days of incubation.

[Generation of Antibiotic Tolerant Bacterial Persisters in Immunocompromized Patients with Hematologic and Malignant Diseases: A New Problem of Health-Care Associated Infections].

Background: Antibiotic tolerance (AT) represents one of the causes of the phenomenon of antibiotic resistance that allows escape of non-replicating metabolically inert microorganisms (persisters) from any antibiotics attack because molecular targets of antibiotics are lacking thereby creating the potential for chronic infections. Aims: Determine the heterogeneity of the strains of opportunistic pathogens E. coli and P. aeruginosa isolates from children with hematologic malignancies containing bacterial persisters that cause the AT phenomenon. Methods: Children with hematological malignancies were divided into 2 groups according to the intensity of antibiotic treatment of infectious complications. Ciprofloxacin-induced persisters were quantitatively determined in the biological materials obtained from sick children. Results: Within the clinical isolates of E. coli and P. aeruginosa, about a third of the strains belong to high-persisting. The numbers of persistent forms of bacteria did not correlate with a minimal inhibitory concentration values ciprofloxacin (r=0.148, n=25, p>0.05). Interestingly, higher level of formation of persistent E. coli and P. aeruginosa, is associated with higher frequencies of infection attacks, massive antibiotic use and unfavorable course of the disease in children. Conclusions: Therefore, detecting the persistent forms of bacterial pathogens including those associated with the health-care associated infection, specifically, in immunocompromised patients, should be included into the contemporary algorithms of microbiological observation and monitoring of patients and intrahospital environment.

[Actual nutrition of patients suffered from hemorrhagic fever with renal syndrome].

The aim of the article is to study actual ration of patients suffered from hemorrhagic fever with renal syndrome (HFRS) and its interaction with the development of arterial hypertension (AH). 296 men aged 20­59 suffered from HFRS were under the care of physician within the period of 1 to 6 years. Among this group 49 cases of arterial hypertension have been registered after HFRS. Frequency method of food product consumption was used to define nutrition. A Russian questionnaire published by Institute of Nutrition (1997) was used. Actual nutrition in men suffered from HFRS is marked by basic nutrients unbalance that is: excessive cholesterol and fat consumption (due to saturated fatty acid), polyunsaturated fatty acid deficiency, sugar overuse and animal protein prevalence over vegetable proteins in patient ration. Atherogenic shift in a ration of patients with AH and suffered from HRFS has been exposed more strongly in all aged group but mostly evident in patients aged 40 and after. Alcohol consumption in men with AH and suffered from HFRS is higher than in healthy peers. Interaction between atherogenic unbalance on the main nutrients in patients with HFRS and arterial hypertension has been defined. Consumatory behavior correction is to be taken to prevent arterial hypertension in recovered patients suffered from HFRS.

[Microbial dormancy and prevention of healthcare-associated infections].

Healthcare-associated infections (HCAI) remain one of the most challenges of modern health care and assume increasing social and medical significance. The specific features of HCAI are frequent recurrences and inefficiency of antibiotic therapy, a reason for which is antibiotic resistance in microorganisms. The review discusses antibiotic resistance, a form of antibiotic tolerance (AT), and its role in the development of HCAI. It also describes essential differences between AT and antibiotic tolerance at the cellular and molecular genetic levels. Relationships between AT and dormancy of microorganisms, pathogens of HCAI, are discussed. The paper gives the data available in the literature on how AT occurs in HCAI pathogens and discusses the diagnosis of this condition. It also analyzes the literature data on pharmacological attempts to overcome AT and discusses novel approaches to antibiotic therapy for HCAI.