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Introduction. In modern reality the effectiveness of disinfection measures is often complicated by rapid development of microbial resistance to known disinfectants, therefore a constant search for new effective, safe disinfectants and compositions is necessary. Polyoxometallates (POMs), especially Keggin’s heteropolyacids (HPAs), are a promising class of inorganic compounds with a broad biological activity, including antiviral and antibacterial ones. So the research of HPAs toxicity and bactericidal activity for the creation of new disinfectants or optimization of known disinfectants by combining with HPAs are essential and actual. Materials and methods. HPAs samples H3PW12O40, H3PMo12O40, H4SiW12O40, H4SiMo12O40, H4PMo11VO40, H5PMo10V2O40, H4PW11VO40 were evaluated by the cytotoxicity index (IC50) in three cell lines by the MTT method using MTT-reagent 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-2H-tetrazolium bromide. HPAs acute toxicity in white mice (administration into the stomach and intraperitoneally) was tested in accordance with GOST 12.1.007-76. Bactericidal activity of HPAs and compositions with hydrogen peroxide was determined against test microorganisms S. aureus and E. coli by the suspension method. The results were supplemented by electron microscopic examination. Results. Vanadium-containing HPAs structures had higher cytotoxicity. All HPAs corresponded to hazard class III in terms of acute toxicity. Bactericidal activity of HPAs and HPAs combinations with hydrogen peroxide was revealed. The incorporation of two vanadium atoms into HPAs structure increased the bactericidal activity. Electron microscopic examination showed more pronounced morphological changes in the ultrastructure of E.coli treated with HPAs / hydrogen peroxide combinations. Mechanism of the bactericidal activity may be associated with HPAs penetration through a damaged membrane of porin channels of bacterial cells. Explanations are also given for another possible mechanism of HPAs action. Limitations. The study is limited to researching toxicological characteristics and bactericidal properties of HPAs, their combinations with hydrogen peroxide. The limited number of HPAs and disinfectants samples is associated with the complexity of the biological experiments. The choice of three cell lines is determined by three different sources of their origin. The suspension method for assessing the antimicrobial activity of substances was performed under the relevant GOST. Test cultures of S. aureus and E. coli were used, other pathogens were not considered. The experiments in vivo were carried out under guidelines for the protection of experimental animals, and their limited number is due to the cost of animals and current ethical views on experiments in vivo. Conclusion. It has been shown that prospects of both HPAs research and combining HPAs with disinfectants having a different mechanism of action in order to enhance a disinfecting effect and reduce the risk of developing microbial resistance to disinfectants.

Research оbjective.To determine the effect of ozone therapy on clinical indicators and the state of immunity in children with moderate persistent allergic rhinitis. Material and methods. The study included children aged 5-10 years with moderate persis-tent allergic rhinitis, which were divided into two groups depending on the therapy. The first group of patients with allergic rhinitis received complex conventional therapy, the second group of patients with allergic rhinitis received complex treatment in combination with ozone therapy. Clinical parameters were studied in patients with allergic rhinitis, parameters of im-munological reactivity were investigated during periods of exacerbation of the disease and clinical remission. Results. It was found that the inclusion of ozone therapy in the complex treatment of patients of the second group ensured a faster onset of complete clinical remission (3.7 days earlier than in the first group of patients) and normalization of most immunity parameters, and also increased the expression of toll-like receptors on leukocyte cells. The duration of complete clinical remission in the group of patients with allergic rhinitis who received complex treatment in combination with ozone therapy (9.3 + 2 months) more than doubled (2.4 times) its duration in the group of patients with allergic rhinitis who received complex conventional therapy (3.9 + 0.3 months).

Objective. To determine the effect of ozonotherapy on the clinical indicators and immunological reactivity state in children with a moderate course of persisting allergic rhinitis. Materials and methods. Children aged 510 years with a moderate persisting allergic rhinitis were under observation. They were divided into two groups depending on the therapy applied. Group I of allergic rhinitis patients received a complex generally accepted therapy, group II of allergic rhinitis patients a complex therapy associated with ozonotherapy. Clinical indices and immunological reactivity parameters were studied during exacerbation and clinical remission in allergic rhinitis children. Results. Ozonotherapy, included into a complex treatment of group II patients, was established to promote a faster occurrence of full clinical remission and normalization of most parameters of immunological reactivity. Duration of a full clinical remission in the group of allergic rhinitis patients, who received a complex therapy associated with ozonotherapy, more than twofold exceeded its duration in the group of allergic rhinitis patients receiving a complex generally accepted therapy. Conclusions. The data obtained indicate high clinical, immunomodulating and antirelapsing effect of ozonotherapy that allows recommending its wide use in complex of medical measures among children with persisting allergic rhinitis.

Successful formation of electronic interfaces between living cells and electronic components requires both good cell viability and performance level. This paper presents a technology for the formation of nanostructured arrays of multi-walled carbon nanotubes (MWCNT) in biopolymer (albumin) layer for higher biocompatibility. The layer of liquid albumin dispersion was sprayed on synthesized MWCNT arrays by deposition system. These nanostructures were engineered using the nanosecond pulsed laser radiation mapping in the near-IR spectral range (λ = 1064 nm). It was determined that the energy density of 0.015 J/cm2 provided a sufficient structuring of MWCNT. The structuring effect occurred during the formation of C–C bonds simultaneously with the formation of a cellular structure of nanotubes in the albumin matrix. It led to a decrease in the nanotube defectiveness, which was observed during the Raman spectroscopy. In addition, laser structuring led to a more than twofold increase in the electrical conductivity of MWCNT arrays with albumin (215.8 ± 10 S/m). Successful electric stimulation of cells on the interfaces with the system based on a culture plate was performed, resulting in the enhanced cell proliferation. Overall, the MWCNT laser-structured arrays with biopolymers might be a promising material for extended biomedical applications.

In this study we have developed a biocompatible current-conductive coating based on carbon nanotubes and bovine serum albumin and have shown its efficiency in culturing cells in vitro. We investigate the proliferation of human embryonic fibroblast (HEF) cells, which were subjected to electrical stimulation when cultured on carbon nanotube surface. A weak increase in proliferation is demonstrated at stimulating field pulses up to 100 mV. It is assumed that the transport mechanism accompanied by higher synthesis of proteins and their polymerization may increase proliferative activity at low voltages. At higher voltages the motility and spatial organization of HEF cell is observed. As a result, a novel technique of supplying the cells with electric field through a system of micro- and nanosized electrodes and a biocompatible composite have been developed.