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Prenatal hypoxia remains the leading cause of infant mortality and severe disability in newborns. Disturbances in the development of fetal brain structures and functions due to hypoxic damage are the main trigger for the development of severe neurological disorders and accelerated neurodegeneration processes and can also be the cause of epileptiform activity in the postnatal period. Herein, the role of chronic prenatal hypoxia on the functional state of C3H+C57Bl6 hybrid mice during the first three weeks of postnatal development and the risks of developing epileptiform activity when provoking audiogenic seizures were assessed. Exposure to chronic prenatal hypoxia was found to increase the risk of neonatal mortality and developmental delay in the surviving individuals in the first two weeks of the postnatal period. It was shown that one of the causes of the failure of adaptation might be the disruption of the functional activity of the mitochondrial apparatus of brain cells mediated by the disruption of the first and second respiratory chain complexes. Exposure to chronic prenatal hypoxia has no significant effect on the increased risk of seizure activity in mice during audiogenic stimulation in late postnatal development, does not activate the development of persistent neurological deficit, and does not significantly affect the cognitive functions and learning ability of animals.

The study of mitochondrial DNA (mtDNA), particularly the hypervariable segment (HVS1) region, is widely used to reconstruct a population's history, structure, and origin. The origin of the Sakha people living in the north-east of Russia has been discussed for more than 300 years, but up to the present time many aspects of their ethnogenesis remain unclear. In order to clarify the migration routes of the ancient ancestors of the Sakha, we analyzed the mitotypes of 69 unrelated representatives of this ethnic group, whose belonging to the ethnic group was traced to the third generation. In the studied Sakha group, we identified 33 mitotypes, the distribution of which by haplogroups approximately coincides with the data of other studies. The results of a comparative study of Sakha mitotypes according to EMPOP data and literature sources revealed a wide distribution of the identified mtDNA HVS1 haplotypes in many populations of Eurasia. A comparison of the obtained mitotypes with the results of mtDNA sequencing of ancient samples shows that most of the mtDNA lines of modern Sakha have long been located on the territory of Yakutia. West Eurasian and East Asian mtDNA lines were incorporated into the Sakha genome at different times in different ways. The results obtained contribute to a better understanding of the routes of ancient migrations of the ancestors of the Sakha population.

The aim of the work was established as to study the effect of low-intensity laser therapy (LILT) on the morphology of neutrophils by the method of interference microscopy in correlation with metabolic parameters in the use of modulators which permits to assess the contribution of various structures of neutrophils to the realization of LILT effect. There was in vitro research. The neutrophils of rats served as the object of research. The neutrophils were incubated with adrenalin, cortisol, and β-blockers of adrenoreceptors. The effect of LILT in combination with a preliminary incubation of these substances was studied. Autonomous laser shower MarsiK (R&D company “Petrolaizer,” Saint Petersbourg), a laser therapeutic complex for animals, was used as a laser irradiation source. The wavelength of the irradiation was 830 nm, and the total power was 90 MW. The phasometry of neutrophils was studied by the laser modulation interference microscopy method, the processes of lipid peroxidation were analyzed by the malondialdehyde concentration, and the ATP concentration was defined by spectrophotometry. LILT provoked unidirectional changes in indices in the groups where the neutrophils were incubated with adrenalin, cortisol, and adrenoreceptor blockers. It manifested in the intensification of lipid peroxidation, increase in ATP concentration, and on the other hand, an increase in phase diameter of neutrophils regarding indicators without the impact of LILT. It is shown that the LILT effect intensity may be modified depending on stress realizing hormones (adrenalin and cortisol), β-blocker of adrenoreceptors. It permits us to suppose that the LILT effects may be realized in different ways depending on the state of the cells.

At present, it can be noted that COVID-19 is the most serious challenge to the international health care system in its recent history. Extremely high rates of morbidity and mortality dictate the need for a more detailed study of the pathogenetic aspects of the developing infectious catastrophe. Besides respiratory distress syndrome, systemic inflammatory response syndrome, COVID-19 is characterized by polyvalent disorders of the mechanisms of systemic hemostasis, which has reflected in an increase in the number of venous thromboembolic complications in the overall structure of morbidity and mortality. The given literature summarizes the information on COVID-associated coagulopathy and its effect on changes in the clinical and epidemiological characteristics of venous thromboembolic complications.

Conditions were determined for the identification of cholesterol in erythrocyte membranes by the fluorescent method using amphotericin B as a probe. We performed a comparative analysis of electronic absorption and fluorescence spectra of cholesterol, amphotericin B, and the products of their interaction, and determined the optimal wavelengths for excitation (328 nm) and recording (468 nm) of fluorescence. Amphotericin B stained cholesterol in membranes was visualized by fluorescence microscopy. It was shown that the registration of emission band at 468 nm on fluorescence spectra of free and membrane-bound cholesterol can serve as a marker of the presence of this lipid in the samples.

Pseudomonas syringae is a widely distributed bacterial epiphyte of plants. When the temperature of the environment drops below zero, P. syringae can serve as biological ice nuclei due to the presence of specialized ice-nucleating proteins. This property has found application in various fields, but despite its evident importance, the molecular mechanisms behind protein-induced freezing have remained largely elusive. One of the problems in the study of the ice-nucleating process is the difficulty of carrying out experiments with freezing/melting solutions at near-zero temperatures. The experimental design implies special requirements for the equipment used and measurement technique. In this work, we used an experimental setup assembled from a dry thermostat that maintains a constant temperature and an accurate digital thermometer. We experimentally tested the possible sources of errors of the setup. As a result, we have shown that the accuracy of determining the freezing temperature of liquids and the coexistence of ice and water is mainly determined by the accuracy of the thermometer. The accuracy of determining the melting point of ice depends on the volume of the sample and is systematically underestimated in our setup. Using the proposed experimental technique, we performed a comparative study of P. syringae and E. coli cells, which revealed that P. syringae cells affect not only the freezing point of the solution but also the temperature of the coexistence of ice and water. The observed effect can be explained by the binding of P. syringae cells to the ice surface.

The widespread occurrence of drug-resistant urogenital mycoplasmas and the high rate of their genetic variability make it possible to consider Mycoplasma hominis as a natural reservoir of antibiotic resistance determinants. Multiple drug resistance of many bacterial types is due to the active elimination of the antibiotic from the cell through various efflux systems. The genome structure of ten clinical isolates Mycoplasma hominis was studied using next-generation sequencing. The molecular genetic characterization family MATE proteins of Russian isolates M. hominis genes using bioinformatics analysis was obtained in the first. It has been established that proteins of the transport systems (ABC-transporters) and MATE play an important role in the formation of antibiotic resistance in urogenital mycoplasmas. The activity and functioning of transport systems are associated with the presence of mutations in the genes encoding regulatory proteins. Efflux systems should be considered as promising potential targets in the creation of new generation antibacterial drugs.

Purpose of the study: substantiation of indications and assessment of results X-ray endovascular treatment of "critical" PE in patients with acute hemorrhagic cerebrovascular accident. Material and methods: the study included 47 patients with acute violation of cerebral circulation for hemorrhagic and mixed types complicated by massive pulmonary thromboembolism of high risk, with "critical" manifestations of right ventricular failure. Depending on the method of PE treatment used, the patients were divided into 2 groups: the study group (17 people), in which endovascular mechanical fragmentation of thromboembols was performed, and the control group (30 people), in which only basic intensive therapy was used. Results: patients of the study group underwent thromboembolic fragmentation in order to transfer embolism of the trunk and the main branches into embolism of smaller branches of the pulmonary artery. Technical success of the procedure (destruction of the central thromboembolus) was achieved in 100% of the cases. 14 patients (82.4%) showed positive clinical dynamics in the form of an improvement in the general condition, a decrease in pressure in the pulmonary artery, and a decrease in the volume of the lesion of the pulmonary bed according to CT angiography. Three patients (17.6%) died in the early postoperative period. In the control group of 30 patients, 25 patients died, hospital mortality was 83.3%. Conclusion: the method of catheter endovascular fragmentation of thrombi for the treatment of "critical" pulmonary embolism in patients with acute hemorrhagic cerebrovascular accident leads to a rapid and safe decrease in pulmonary artery pressure. 

The actuality of the problem of thermal trauma is determined by its high prevalence. Severe disorders of central, regional and peripheral hemodynamics are developing with a predominant violation of microcirculation and metabolic processes in the body during burn disease. Promising NO donors suitable for biomedical use are dinitrosyl iron complexes (DNIC). The aim of the study was to evaluate the effect of DNIC on the state of microcirculation in normal conditions and on the model of combined thermal trauma (CTT). The experiments were carried out on white male rats of the Wistar line. CTT (contact burn on the area of 20% of the body surface and thermal inhalation exposure to hot air and combustion products for 20-30 seconds) was applied under anesthesia. Animals with CTT were treated daily with intraperitoneal injections of a 10% DNIC solution (1 ml; 0.3 micromol/l). Laser Doppler flowmetry was used to assess the dynamics of the microcirculation state. The physiological and biochemical mechanisms of microcirculation disorders in CTT are revealed in the work. There was an increase in the endothelial, neurogenic and respiratory components of microcirculation, microhemodynamics of the border area of the burn, and the index of the microcirculation bypass. It was shown that when using 0.3 micromol/l of DNIC in rats under normal conditions, there is a decrease in the neurogenic and respiratory components, an increase in perfusion and the myogenic component of the microcirculatory channel. The role of 0.3 micromol/l of DNIC in the normalization of microcirculation in CTT was established.