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The visceral system can influence consciousness and emotions. In this paper, we investigated whether the processing of short-term emotional stimuli along different phases of the cardiac cycle is selectively regulated. Emotional and neutral faces were presented to the volunteers during cardiac systole, when the release of blood from the heart causes arterial baroreceptors to centrally signal the strength and time of the heartbeat, and in diastole, the period between heartbeats when the baroreceptors are at rest. Participants passively observed the faces appearing in the oddball paradigm in immersive virtual reality (VR). Combining electroencephalography and electrocardiography, cardio synchronous ERP was recorded. The ERP data at the occipital Oz electrode demonstrate the dependence of emotional stimuli in respect to the cardiac cycle. ERP in VR were higher during diastole than systole. More specifically, the cardiac phase influenced late component P300 of the ERP, did not influence early P100 and affected P200 only to angry face. This new evidence that events related to cardiac function can modulate emotional perception in virtual reality might be one more prime example of how body feedback shapes emotions.

The paper focuses on studying the rheological properties of erythrocytes in patients with a new coronavirus infection in the acute period and during early convalescence. A significant decrease in erythrocyte membrane plasticity was found in all patients in the acute period of the disease and every second recovering patients in the early post-COVID period. An increase in the degree and rate of erythrocyte aggregation in a quarter of cases, regardless of the observation period, was accompanied by inhibition of erythrocyte disaggregation mechanisms, which can serve as a pathophysiological basis for the formation of hemorheological disorders both in the micro- and macrovasculature in the first 3 months after recovery.

B. pumilus metalloproteinase was firstly isolated and characterized by Kazan Federal University scientists. Primary structure analysis showed that the novel enzyme has no analogs among prokaryotic enzymes and occupies an intermediate position between two large families of the metzinkin clan metalloproteinases – adamalysins and astacins. These families are mainly represented by eukaryotic enzymes, which play an important role in human life and health. A more detailed study of the structure and functions of novel metalloproteinase requires an efficient expression system. B. pumilus metalloproteinase gene (mprBp) was cloned into the pGP382 expression vector under a strong constitutive promoter of the degQ36 gene (P_degQ36). The resulting construct was used to transform B. subtilis Δ6 strain. This strain was constructed by CRISPR/Cas9 genome editing technology with deletion of some prophage genes of B. subtilis 168. The functional role of prophage genes is poorly understood. It is possible that prophage deletion will increase the expression of secreted enzymes. For the transformed strain we determined the dynamics of growth and accumulation of proteolytic activity by hydrolysis of azocasein. The dynamics of proteolytic activity accumulation by this strain has a different character in contrast to the protease-deficient strains carrying the gene of the investigated enzyme. The result of this work was to obtain an effective producer strain of adamalizin-like metalloproteinase of B. pumilus, which can be used in the production of the enzyme for subsequent studies.

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.

The dynamics of electroencephalographic (EEG) reactions were analyzed under a combination of resonance scanning and EEG-guided adaptive neurostimulation in the process of the cognitive rehabilitation of patients with post-COVID syndrome (PCS). It has been shown that the introduction of resonant scanning before adaptive neurostimulation makes it possible to observe the dynamics of resonant EEG reactions, provides activation of potential EEG oscillators of the brain, and increases the responsiveness of the brain to subsequent adaptive neurostimulation. Complex treatment procedures, due to the progressive involvement of resonant and adaptive mechanisms and mechanisms of neuroplasticity, contribute to the cognitive rehabilitation of patients with PCS, which manifests itself in the normalization of the EEG, a decrease in stress levels, and an improvement in emotional state and mood of the patients.