We developed a scheme of consecutive replacement of complex components of a known Brucella medium containing peptones and blood with simple analogs and created a synthetic medium for Helicobacter pylori culturing. H. pylori cells require hemic iron for their growth; an appreciable increment in biomass was ensured by hemoglobin, but not simpler hemocontaining compounds (hemin and cytochrome C). Glutamine (20 g/liter) was used as the main nitrogen-containing component, and other amino acids were added in trace amounts. Adhesion was provided by adding agarose gel (0.1%) also promoting the increase in biomass. The proposed medium of a certain chemical composition differs from the known foreign analogs by the presence of hemocontaining component (hemoglobin), short period of exponential growth, and appreciable accumulation of cell protein.

Atopic dermatitis (AD) is a multifactorial genetically determined inflammatory skin disease characterized by itching, chronic course, age-related features of localization and lesion morphology. Atopic dermatitis is caused by complex interactions between genetic, immunological, and environmental factors. The barrier function of the skin is impaired in atopic dermatitis. Antimicrobial peptides, e.g., LL-37, b-defensins are involved in maintaining the skin barrier function (especially, intercellular contacts). An imbalance of antimicrobial peptides may cause different disorders, including allergic pathologies. The aim of this study is to investigate gene expression profile of the HBD1 and LL37 encoding antimicrobial peptides in the samples of skin and blood mononuclear cells obtained from the children with moderate and severe atopic dermatitis before and after treatment. By means of real-time polymerase chain reaction, the levels of HBD1 and LL37 gene expression were evaluated in the samples. Statistical analysis showed significantly increased (p 0.017) expression levels of both HBD1 (H-test = 24.76; 2, n = 72; p = 0.00001), and LL37 genes (H-test = 15.69; 2, n = 72; p = 0.00039) in blood cells of AD patients compared to the control group, as well as decreased (p 0.05) levels of HBD1 expression in the affected skin compared to the control group. Our data on the cathelicidin gene in the skin do not differ from the literature data, since its expression is reduced in AD. In our series, an increase of the gene expression was revealed in PBMCs. The HBD1 peptide is expressed in both monocytes and macrophages, representing a link between innate and adaptive immunity. In our study, the expression of the HBD1 gene was increased only in blood, thus suggesting activation of innate immunity components at the systemic level in response to inflammation. Of importance, understanding the role of immunological markers in AD will help to develop novel prognostic approaches in management of the patients with atopic disorders. Therefore, one should understand pathogenetic mechanisms of allergic diseases.

Aim. In this study we developed and characterized a mouse model of secondary S. aureus and S. pneumoniae pneumonia following influenza virus infection with H1N1 pandemic and laboratory strains and their reassortment. Materials and methods. BALB/с mice were infected intranasally with A/California/04/2009/(H1N1 pndm), A/Puerto Rico/8/34 or their reassortment NIBRG-121xp followed by different strains of S. аureus и S. pneumoniae. The pathogenicity of infection was assessed by mouse survival and weight change, viral titre and bacterial count in the lungs. Results. It was shown that the infection of mice with three strains of the H1N1 influenza virus with a comparable level of pathogenicity leads to a different severity of secondary bacterial infection. The mouse adapted A/California/04/2009 pandemic strain possessed the greatest ability to alter antibacterial immunity. Conclusion. An experimental model of post-influenza bacterial pneumonia utilizing three strains of the H1N1 influenza virus and various strains of S. aureus or S. pneumoniae was established. The ability of viruses to provoke bacterial superinfection of different severity is characterized.

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A method for measuring urease activity in biopsy specimens and Helicobacter pylori cultures from these specimens is proposed. The method is based on measurement (with a portable pH-meter) of the rate of pH changes in a reaction mixture consisting of buffer, substrate (urea), and biopsy specimen or bacterial cells. This method revealed that urease activity of biopsy specimens correlated with that of H. pylori suspension in the same experiment. High urease activity was found in biopsy specimens containing the greatest number of Helicobacter cells; only one of 14 specimens free of H. pylori cells showed no urease activity. Introduction of this method into clinical practice will help to evaluate the contribution of H. pylori to the pathological process.