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The problem of the influence of inflammation on the processes of higher nervous activity is still relevant. In particular, it implies an analysis of the safety and effectiveness of biological regulators’ effects with neurotropic and immunomodulatory potential. The study examined the effects of Salmonella tiphy LPS on behaviour and cognitive function in adult male Wistar rats with different levels of melatoninergic system activity, using various tests. It was found that daily injection of LPS to rats of the group А (50 μg/kg, i.p.) for 10 days leads to the formation of a special pattern of behavior with a low level of tentative research activity in the presence of increased anxiety. The rats of the group В received combined exposure to LPS (50 μg/kg, i.p.) and melatonin (5 mg/kg, orally) distinguished a higher level of various variants of motor and research activity in conditions of relatively low anxiety in contrast to the rats of the group А. The paper discusses the features and mechanisms of the formation of "painful" behavior in an experimental model of inflammation, depending on the level of activation of the components of the melatoninergic system. 

Noroviruses with the GII.P16 polymerase gene have long been considered rare. However, since 2015, there have been reports from different geographical regions about the spread of new recombinant strains of norovirus in which GII.P16 polymerase is associated with a capsid protein of various genotypes. In the autumn of 2016, a sharp increase in the frequency of detection of noroviruses was observed in Nizhny Novgorod, which coincided with the appearance of new recombinants GII.4_Sydney and GII.2 – with GII.P16 polymerase. Based on the sequences of the RNA-dependent RNA polymerase gene present in the GenBank database, a phylogenetic analysis of noroviruses with GII.P16 specificity was performed by constructing Bayesian phylogenetic trees. Analysis of amino acid sequences showed that representatives of the novel variant of the GII.P16 polymerase gene had five substitutions compared to earlier strains. These substitutions are located near sites responsible for the enzyme activity of polymerase and could affect the transmissivity of the virus. Acquisition of a novel variant of the GII.P16 polymerase gene by noroviruses with different capsid protein genotypes probably provides certain advantages for recombinants and creates prerequisites for their wide distribution.

Morganella morganii is an important clinical pathogen with fast-paced multidrug resistance and virulence. Probiotics with potent antimicrobial activity are considered as a promising alternative to antibiotics in infection treatment. We isolated 12 lactobacilli strains of human and plant origin and characterized their beneficial properties focusing on their antagonistic activity against M. morganii. Tolerance to the hostile gastrointestinal environment, surface properties (hydrophobicity and autoaggregation), and acidification rate values varied considerably between strains and were strain-specific. Most Lactobacillus strains showed antibiotic resistance profiles typical for lactobacilli. Lactobacilli demonstrated inhibitory activity towards the growth of M. morganii in the agar-overlay assay, produced bacteriocins and coaggregated with M. morganii cells, but did not affect the growth of the pathogen during co-culturing in the mixed-species biofilms. Lactiplantibacillus plantarum strain FCa3L was selected as the candidate strain with potential probiotic properties for further investigation.

Using fluorescence microscopy, morphological analysis of cell growth, and PCR analysis, we have shown that deletion of the Satb2 transcription factor in mouse cortical neurons results in impaired neuronal network development in vitro. It was found that primary cell cultures of the cerebral cortex obtained from Satb2-null mice are not able to form a developed network of neurites during 5 days of cultivation, while cells from control mice are characterized at this time by a fully developed network of neuronal processes. Analysis of protein kinases expression involved in the processes of neuron differentiation and neurites growth showed that deletion of Satb2 leads to suppression of the expression of genes encoding protein kinase C (PKC), protein kinase B (Akt/PKB), mitogen-activated protein kinase 8 (MAPK8) and Ca²⁺/ calmodulin-dependent protein kinase II (CaMKII), while not affecting the expression of phosphatidylinositol 3-kinase (PI3K). Activation of neurites outgrowth and differentiation of Satb2-null neurons was achieved by the application of exogenous activators of Akt/PKB, CaMKII and PI3K, but not PKC, the expression and activity of which is probably completely suppressed by the deletion of Satb2.

Pressure sores remain an important clinical problem with significant socioeconomic implications. The pressure sores treatment via reparative processes activation in tissues by low-temperature plasma discharges was studied in the present work. Low-temperature plasma discharges were initiated by high-frequency 0.11, 2.64, 6.78, and 13.56 MHz current. It is shown that the optimal current frequency for the generation of the cold plasma is 6.78 MHz. This current frequency was used in clinical studies of pressure sores treatment with cold plasma discharges of the glow type. The efficiency of treatment was evaluated by analysis of histological samples, histochemical and bacteriological methods. Low-temperature plasma discharge treatment improved the dynamic of pressure sore healing, activated reparative processes in injured tissues, and decreased bacteria numbers in a wound. The most pronounced effect was observed after 14-21 days. The low-temperature plasma discharges accelerated pressure sores healing from 14 to 16% compared with non-treated by cold plasma wound. The effect depended on the pressure sores etiology. Low-temperature plasma discharges of glow type may be considered as an effective approach to pressure sores therapy.