The combined plasmid construct pcDNA_VEGF165/Ang-1 has a pronounced angiogenic effect under the conditions of the modeled experimental chronic insufficiency of arterial blood supply to the limb. A single local administration of pcDNA_VEGF165/Ang-1 at a dose of 100 μg into the ischemic skeletal muscle of laboratory animals starting from the 14th day after therapy stimulates the formation of microcirculatory bed vessels with a statistically significant increase in the number of capillaries. The use of the gene therapeutic substance pcDNA_VEGF165/Ang-1 allows for complete restoration of impaired blood supply in the muscles of the thigh and lower leg of the rats by the 28th day of observation, creates conditions for maintaining a long-term positive effect until the end of the experiment (42nd day) while maintaining the number of blood vessels in one muscle fiber not lower than the healthy tissue indicator.

Post-COVID syndrome is poorly defined complex of different symptoms predominantly functional disorders, which are diagnosed in 30–70 % of patients after COVID-19 infection.

To determine the pathogenic basis of neurological symptoms of post-COVID syndrome 105 patients (48 men, 40 women, mean age 47 [40; 54.5]) with post-COVID syndrome in the period from 3 months after COVID-infection and 10 people of the control group (4 men, 6 women, mean age 40 [28; 50]) were examined using structural magnetic resonance imaging (MRI) and magnetic resonance spectroscopy.

After dividing of post-COVID patients group into three subgroups according to the severity of complaints no significant morphological differences in brain structures were determined according to MRI data. However was revealed interhemispheric asymmetry as the cerebral cortex thinning in left frontal lobe ( p = 0.006) and higher left temporal horn of the side ventricle ( p = 0.007) in subgroup post COVID patients with severity symptoms. Was revealed decrease of the N-acetylaspartate/creatinine (NAA/Cr) ratio in the anterior part of the cingulate gyrus on both sides ( p = 0.025 on the right, p = 0.025 on the left) and in the center semiovale on the right sides ( p = 0.001), an increase of choline/creatinine (Cho/Cr) ratio in the anterior cingulate gyrus on both sides ( p < 0.01 on the right) and ( p = 0.04 on the left), right next to areas of decreased NAA/Cr ratio. It was also revealed decrease of the myoinositol/creatinine ratio in the center semiovale area on the right ( p = 0.038) and the middle cingulate gyrus on the left ( p = 0.027). According to the functional topography of the brain neuromediation changes in the anterior cingulate gyrus and center semiovale may have clinical correlates as impaired executive functions, memory and mood disturbance what is related to post-COVID syndrome.

Thus we found that neurological symptoms of post-COVID syndrome are based on multidirectional changes in the secretion of NAA and Cho in the cingulate gyrus of the brain without accompanying morphological pathology.

To evaluate the effectiveness of osteogenesis in the peri-implant defect using different scaffold matrices, it is necessary to perform accurate informative studies such as scanning electron microscopy and spectral analysis.

Objective: to study the structure and elemental composition of bone tissue on the surface of dental implants in the periimplant defect after the introduction of scaffolds based on a spongy-cortical mixture of allogeneic origin, collagen, and hydroxyapatite/β-tricalcium phosphate with pre-implanted ectomesenchymal cells.

On the obtained peri-implantitis model in 12 experimental one-year-old North Caucasian sheep, surgical treatment of the peri-implant defect was performed using scaffolds on a matrix of spongy-cortical mixture of allogeneic origin (group 1), collagen (group 2), and hydroxyapatite/β-tricalcium phosphate (group 3). Dental implants with SA-surface (1 subgroup in each group) and CA-surface (2 subgroup in each group) were installed. Scanning electron microscopy and spectral analysis were performed 3 months after extraction of dental implants together with bone regenerate.

Microelement composition of bone regenerate around dental implants of group 2 of subgroup 2 differed significantly from the composition of other samples. Content by weight of oxygen (53.9 %), calcium (11.36 %), phosphorus (7.04 %) corresponds to the composition of calcium hydroxyapatite, which indicates high mineralization of newly formed bone tissue.

The most effective osteogenesis was noted in the subgroup 2 of group 2, where the organic component – collagen – acted as a matrix for the scaffold.

Ischemic heart disease (IHD) remains a leading cause of mortality and disability worldwide despite advances in treatment. Genetic factors (polymorphisms of the genes) play a significant role in the pathogenesis of IHD. Studying polymorphisms may improve understanding of genetic predisposition to IHD and aid in personalizing therapeutic approaches.

The aim of the study is to investigate the distribution of genotypes and alleles of the Leu33Pro (rs5918) polymorphism in the ITGB3 gene and the Thr715Pro (rs6136) polymorphism in the SELP gene in groups of patients with IHD and healthy individuals.

The study included 209 participants divided into three groups: healthy individuals (n = 31), patients with chronic IHD without indications for invasive coronary angiography (n = 30), and patients with IHD who underwent elective PCI (n = 148). Genotyping of ITGB3 (Leu33Pro) and SELP (Thr715Pro) polymorphisms was performed using polymerase chain reaction with reagent kits manufactured by “Syntol” (Russia). Statistical analysis was conducted using the StatSoft STATISTICA 10.0 software. Non-parametric methods, including the Mann–Whitney test, Kruskal–Wallis test, and Fisher’s exact test, were used; the level of statistical significance was set at p < 0.05.

The study demonstrated that the distribution of genotypes and alleles of the Leu33Pro (rs5918) polymorphism in the ITGB3 gene and the Thr715Pro (rs6136) polymorphism in the SELP gene in the studied population, as well as in each group, conforms to Hardy–Weinberg equilibrium. Analysis of genotype and allele frequencies across codominant, dominant, recessive, and overdominant inheritance models revealed no statistically significant differences between the groups. For the Leu33Pro (T˃C, rs5918) polymorphism in the ITGB3 gene, allele T predominated (ranging from 79.53 to 82.76 %); however, intergroup differences in genotypes and alleles did not reach statistical significance. A similar pattern was observed for the Thr715Pro (rs6136) polymorphism in the SELP gene, where genotype and allele frequencies did not differ between groups in any of the inheritance models analyzed.

The results of this study revealed no statistically significant differences in the distribution of genotypes and alleles for the two investigated polymorphisms (Leu33Pro (rs5918) in the ITGB3 gene and Thr715Pro (rs6136) in the SELP gene) between patients and healthy individuals. The absence of statistically significant differences highlights the importance of further largescale studies considering ethnic, and other risk factors.

The COVID-19 pandemic determines the relevance of conducting a study of the gender and age structure in hospitalized and deceased patients.The purpose of the study is to identify the patterns of the COVID-19 epidemic process in connection with the gender and age characteristics of hospitalized adults and to identify the gender and age groups wich most susceptible to hospitalization and mortality from COVID-19.

An analysis of the structure of hospitalized and deceased from COVID-19 by gender and age was carried out. Data from statistical registration forms of adults hospitalized in one of the city clinical hospitals in Moscow in 2020–2021 were used. Data processing was carried out using a set of standard statistical methods. To identify risk groups for hospitalization and mortality, statistical correction of the population composition by gender and age was used.

Data on risk groups for hospitalization and mortality among the population of Moscow at the early stage of the COVID-19 pandemic were obtained. It has been established that the risk group for hospitalization with COVID-19 is young men (average age 39.0 ± 5.0 years). They are 1.5 times more likely to be hospitalized with COVID-19 than younger women. According to COVID-19 mortality rate, the risk group is middle-aged (53.1 ± 4.3 years) and elderly (68.3 ± 4.5 years) men, for whom the mortality risk is higher than in women of the same age (3.3 and 2.2 times, respectively). Also at risk for mortality are men of age of 75–90 years, the mortality rate among them was 57 %.

The results of the study allow to identify true risk groups for hospitalization and mortality due to COVID-19, complement new knowledge into the patterns of epidemiological analysis, which is an important component of epidemiological surveillance for making management decisions to the spread prevention of SARS-CoV-2 spread prevention and planning for the provision of medical care for identified gender and age risk groups.

In an experiment on white rats, the parameters of mitochondrial oxidation of small intestine tissue during the incorporation of ¹³⁷Cs were studied by polarographic method. The animals of the experimental group received radioactive feed for 14–30 days, the control group was kept on a standard vivarium diet. Experimental groups with the level of accumulation of radionuclides of 600–800, 3 000–3 300 and 10 000 Bq/kg were formed. The assessment of absorbed doses of internal radiation was calculated from the content of ¹³⁷Cs in rat carcasses. The “inverted intestinal sac” method was used to obtain tissue fragments of the small intestine. Dosimetric control was carried out on a gamma-ray spectrometer LP 4900B (Finland). Experimental data were obtained when working with tissue fragments. The studies reflect the high sensitivity of the small intestine tissue to the effects of internal radiation. Significant changes in the studied indicators of energy metabolism have been revealed. A change in the integral index of mitochondrial oxidation (respiration rate on endogenous substrates) was noted, which consistently increased with an increase in the level of caesium incorporation. The greatest uncoupling effect of 2.4-DNF was detected at the incorporation level of 10 000 Bq/kg. It has been shown that the intensity of tissue respiration on both endogenous and exogenous substrates depends on the level of incorporation of ¹³⁷Cs. It has been shown that the intensity of tissue respiration on both endogenous and exogenous substrates depends on the level of incorporation of ¹³⁷Cs.

The purpose of the work is to establish optimal storage conditions for heparinized human whole blood before launching it into dynamic in vitro test systems of artificial blood flow to assess the hemocompatibility of medical devices.

To conduct the study, blood was collected from donors in a volume of 150 ml using a butterfly needle with a luer-adapter, a catheter and a syringe filled with heparin (1.5 IU/ml). Subsequently, heparinized blood was transferred into test tubes and kept in a thermostat at temperatures of 20, 25, 30 and 37 oC for 40, 50 and 60 minutes, simulating room temperature and human body temperature. As a control sample, solid blood obtained immediately after its fence in donors was used, with the addition of heparin. To study the effect of time and temperature of blood storage on its activation, a number of hematological and immunoenzyme parameters were studied.

Storing whole blood at room temperature initiated activation of platelets and coagulation mechanisms within 60 minutes. The effect of elevated temperatures of 30 and 37 oC was characterized by a statistically significant increase in the content of indicators such as beta-thromboglobulin (by 2.2–2.3 times), thromboxane B2 (by 2.0–2.1 times), prothrombin F1+2 (by 1.6– 1.8 times) and thrombin-antithrombin complex III (by 1.8–2.0 times) after 40 minutes of storage.

It was experimentally established that to assess the hem-proposal of medical products with optimal storage conditions for solid heparinized blood of a person is a storage time of not more than 50 minutes and room temperature of 20–25 °C. The data obtained will help improve the reliability of assessing the blood compatibility of medical devices and, as a result, reduce the risk of adverse consequences for patients.