Introduction. Cerebrovascular diseases are a medical and social problem for developed countries in the second half of the 20th century and the beginning of the 21^st century. The study of special mortality rates makes it possible to study in depth the nature of this pathology, its intensity among the population and to formulate reasoned program solutions aimed at reducing its frequency in the population.
The aim of the research is to identify trends and features of the dynamics of mortality in connection with cerebrovascular diseases in different age and sex groups of Irkutsk Region population.
Materials and methods. The subject of the research is deaths from cerebrovascular diseases among Irkutsk Region population for the period of 2000–2020. A continuous method of statistical observation was used; the grouping of the material was carried out by distributing the deceased by sex and five-year age interval, with subsequent calculation of mortality tables. The dynamics of the quantitative measure of mortality was determined by calculating the matrix of time series indicators.
Results and discussion. For the period of 2000–2020, in the Irkutsk Region, there was a decrease in mortality rates from cerebrovascular diseases both among the male and female population. Mortality rates by sex are higher among the male population, as indicated by the ratio of the ratio of mortality between men and women in all age intervals. The multiplicity of the ratio of indicators increases during the research period from the maximum values of 2.1 times in 2000 to 5.0 times in 2020. The maximum difference shifts from the age of 55–59 to the age group of 40–44. The intensity of mortality reduction in the dynamics of 2000–2020 among the female population is higher than the male. Based on the results of the analysis of the time series, it was found that the age-specific exponent of mortality in the content of 1 % of the mortality increase has a more pronounced quantitative measure for the male population.
Conclusion. As the result of the research, for twenty-year observation period a decrease in mortality rates from cerebrovascular diseases was revealed. The age-specific mortality rate from cerebrovascular diseases in the male population is higher than in the female population. The maximum intensity of the difference in mortality between men and women is reached in the working age groups. The content of the indicator 1% of increase in deaths in the male population is higher than that of the female. State policy in the development and implementation of target-oriented programs for reduction of mortality should be based on thorough analysis of data of administrative districts.

The aim. To study the prevalence of various combinations of polymorphic variants of genes markers of endothelial function and vascular-platelet hemostasis in the development of diabetic foot syndrome.
Materials and methods. In 198 patients with uncomplicated diabetes mellitus and 199 patients with diabetic foot syndrome, the frequency of polymorphic variants of the NOS 786C>T, END1 Lys198Asn, ITGB3 1565T>C (Leu33Pro), F5 1691G>A, F2 20210G>A, MMP9 8202A>G, MTHFR 1298A>C, VEGFA-634C>G genes was studied. Using binary logistic regression analysis, the relationship of various combinations of polymorphisms of the studied genes with the development of diabetic foot was assessed.
Results. In diabetic foot syndrome, the most significant contribution is made by the combination of polymorphic variants of the ITGB3 1565T>C (Leu33Pro) and MTHFR 1298A>C genes. With the development of this complication of diabetes mellitus, a combination of the 1565 TC polymorphism of gene ITGB3 and the 1298AA polymorphism of gene MTHFR is 2.1 times more common. The association of the 1565TT polymorphism of gene ITGB3 and the 1298AC polymorphism of gene MTHFR is 2 times more common in diabetes mellitus without complications.
Conclusion. The combination of the 1565TС polymorphism of gene ITGB3 and the 1298АА polymorphism of gene MTHFR is associated with the risk of developing a diabetic foot and increases the risk of developing this complication by 2.4 times. The presence of a combination of the 1565TT polymorphisms of gene ITGB3 and the 1298AC polymorphism of gene MTHFR is more common in uncomplicated diabetes mellitus, which suggests its protective effect against the development of diabetic foot syndrome.

The purpose of this review was to systematize data on molecular genetic markers of increased risk of cardiotoxic effects, as well as to search for risk and protective variants of candidate genes. Today, the therapy of malignant neoplasms is based on the use of anthracyclines – drugs of the cytostatic mechanism of action. Along with their effectiveness, these drugs can have a cardiotoxic effect on cardiomyocytes by increasing the amount of reactive oxygen species and disrupting mitochondrial biogenesis. Pathological disorders lead to an increased risk of myocardial dysfunction and a number of other cardiovascular pathologies in patients receiving chemotherapy using anthracyclines. The cardiotoxic effect of anthracyclines leads to cardiomyopathy, heart failure, myocardial infarction, and thrombosis. Early detection of cardiotoxic damage leads to reducing the negative effects of these drugs due to changes in chemotherapy tactics. It is known that the risk of cardiotoxic myocardial damage is genetically determined and controlled by more than 80 genes. In this review, the description of basic molecules such as ATP-binding cassette transporters and solute carrier family (SLC transporters), carbonyl reductase, molecules of antioxidant defense, xenobiotic and iron metabolism was performed. In addition, a special attention is paid to the study of epigenetic and post-translational regulation. The available data are characterized by some inconsistency that may be explained by the ethnic differences of the studied populations. Thus, a more detailed research of various ethnic groups, gene-gene interactions between potential candidate genes and epigenetic regulation is necessary. Thus, understanding the contribution of genetic polymorphism to the development of cardiotoxicity will help to assess the individual risks of cardiovascular pathology in patients with various types of cancer, as well as reduce the risk of myocardial damage by developing individual preventive measures and correcting chemotherapy.

Relevance. The relevance of the study is due to the high significance of school anxiety in the formation of psychosomatic diseases and nervous disorders. Identification of risk factors for increased anxiety, one of which is low physical activity, is important for the timely organizing of preventive measures.
The aim: to assess the characteristics of physical activity and school anxiety among schoolboys of secondary school and the cadet corps.
Materials and methods. The observation group consisted of 47 schoolboys studying in a secondary general school at the age of 13–16; the comparison group consisted of 140 schoolboys of the cadet corps. The comparative assessment of physical activity bases on the analysis of the physical education implementation in educational organizations and the results of a survey according to the author’s questionnaire. A comparison was made of the parameters of bioimpedance analysis (BIA) of body composition, the content of cortisol and serotonin in the blood serum, and indicators of the Phillips school anxiety test.
The results. Physical activity in the school system was limited to 3 hours per week, and in the additional education system there are only 14.9 % of schoolboys who devote 6–8 hours a week to sports, which is 3 times less than in the comparison group (46.4 %). Lower values of indicators of physical activity and body composition were found in secondary school boys relative to those in cadet corps (p = 0.015–0.038). The level of cortisol in the blood serum was 1.4 times higher, and the serotonin was 1.2 times less in schoolboys of the schools comparatively to cadets (p = 0.001–0.037). In secondary school schoolboys, relative to cadets, significantly 1.9–3.9 times more often increased values were recorded for the factor general anxiety at school, frustration of the need to achieve success, fear of self-expression, fear of the situation of testing knowledge, fear of not meeting the expectations of others, problems and fears in relations with teachers and general anxiety oppositely directed correlations of weak and moderate strength were established between the frequency and duration of physical education, BIA parameters, cortisol in the blood serum and factors of school anxiety.
Conclusion. The values of the factors of school anxiety schoolboys of secondary general school are higher than in boys of the cadet corps and possibly they are associated with irregularity, relatively low duration of physical activity and the degree of development of metabolically active tissues.

Infectious complications after primary implantation of the hip joint are 0.5–3 %, and in the case of re-endoprosthetics, the risk of periprosthetic infection can reach 30 %. Also, we should not forget about the high percentage (16–20 %) of recurrence of periprosthetic infection of the hip joint, which leads to an unsatisfactory result of treatment up to amputation of a limb or even death of the patient. The reasons for the recurrence of the infectious process can be antibiotic resistance and antibiotic tolerance of microorganisms, as well as the ability of microorganisms to form biofilms on implants. In this regard, there is a constant need to search for alternative means of antimicrobial therapy, as well as to select the optimal ways of their delivery and deposition, which is of practical importance when performing surgical interventions in traumatology and orthopedics to protect the implantable structure from possible infection of the surgical site. One of the methods currently available to combat bacterial infections acquired antibiotic resistance and antibiotic tolerance is the use of natural viruses that infect bacterial bacteriophages. The above suggests a more effective suppression of periprosthetic infection, including persisters that deviate from antibiotics. It is, as a rule, associated with biofilms if used in conjunction with antibiotics and phages, when the use of bacteriophages predetermines the effectiveness of treatment. With the use of sensitive bacteriophages in the treatment of periprosthetic infections, a significant (p = 0.030) reduction in the rate of recurrence of infection (from 31 to 4.5 %) was observed. The use of lytic bacteriophages in traumatology and orthopedics is of great interest for phagotherapy of infections caused by antibiotic-resistant and biofilm-forming strains of bacteria. A clinical study using a single-stage surgical revision with simultaneous application of antibiotics and phages in the treatment of deep periprosthesis infection of the hip joint endoprosthesis, followed by 12 months follow-up for periprosthetic infection recurrence, demonstrated the effectiveness of the use of combined antibiotic and bacteriophages treatment.

Infectious disease COVID-19 caused by the SARS-CoV-2 coronavirus is characterized by high contagiousness, complexity of pathogenesis and unpredictability of the clinical course. In severe cases, which are especially susceptible to men, the elderly and people with underlying medical conditions such as obesity, diabetes, hypertension, cardiovascular and chronic respiratory diseases, the infection leads to respiratory failure and death due to the development of an extensive inflammatory reaction. As a result of many studies, it has been established that one of the leading causes of the severe course and death of patients with COVID-19 is the development of coagulopathy, that is, increased thrombus formation in small vessels due to excessive activity of neutrophils, which form the so-called neutrophil extracellular traps (NETs). Although NETs play a useful role in protecting their host from pathogens, their overgrowth can trigger a cascade of adverse reactions including: the production of antibodies against the host’s DNA (autoimmunization); damage to surrounding tissue; or the occurrence of thromboembolic complications. Therefore, extracellular neutrophil traps and their markers have been identified as targets for new therapeutic strategies aimed at reducing the severity of COVID-19 disease and/or mortality. This article describes the structure of NETs, as well as analyzes the molecular mechanisms that contribute to their overgeneration. In addition, the prospects for COVID-19 therapy aimed at regulating the formation of extracellular traps by creating drugs both limiting the production of NET structures and dissolving their excess amounts in the body of patients are discussed.

The new coronavirus infection (SARS-CoV-2), better known as COVID-19, quickly evolved into a worldwide pandemic with a significant public health burden. Currently, there are no approved drugs or preventive therapeutic strategies to combat infection. Decisions about prescribing many medications are made based on the results obtained in in vitro studies, or expert opinions. Most of the drugs currently used to treat COVID-19 are approved antivirals or antibodies against other diseases. However, there are hundreds of clinical studies underway around the world to discover effective treatments for COVID-19. This article summarizes the results of clinical studies of potential therapeutic drugs used as COVID-19 therapy. Based on this review, it can be concluded that there is still no high-quality evidence to support any of the drugs described below. Until the unambiguous results of randomized controlled trials are available, the use of any of the following drugs is not clinically proven as an effective treatment for COVID-19.

Cardiovascular disease has serious economic and social consequences that affect people, health systems and societies around the world. Ischemic heart disease is one of the main global causes of death of the population, and its growth is predicted in the coming years. This fact continues to be of serious concern to health, social and economic services. Cardiovascular disease remains the most common cause of death, and age-standardized rates are higher for men than for women. Cardiovascular comorbidity increases significantly with age.
The combination of ischemic heart disease and comorbid pathology is noted in cancer incidence, bronchial asthma, non-alcoholic fatty liver disease, type 2 diabetes mellitus, chronic obstructive pulmonary disease, periodontal disease, etc. It is necessary to analyze the existing disease with past diseases, risk factors and predictors available in the patient. The presence of concomitant diseases quite often requires additional diagnostic methods and changes in the tactics of treating coronary heart disease due to the fact that some of them are a contraindication to the use of certain groups of drugs. Periodontal disease includes a wide range of inflammatory conditions that affect the supporting structures of the teeth, which can lead to tooth loss and contribute to systemic inflammation. Periodontal disease is associated with several systemic diseases, one of which is coronary artery disease. It is imperative that clinicians understand the link between periodontal disease and cardiovascular disease. Comprehensive treatment of periodontitis and restoration of a healthy periodontium can help reduce overall inflammation in the body and reduce the risks of coronary heart disease.

This review is devoted to the European subtype of tick-borne encephalitis virus (TBEV). It summarizes and analyzes the information available at the scientific literature on the genetic and biological properties of strains of this virus subtype. A comparative analysis of the complete coding sequences of all currently recognized tick-borne flaviviruses was carried out. It was noted that the differences in TBEV strains included in the European subtype are minimal, which indicates a higher degree of their genetic homogeneity than in strains of the Far Eastern and Siberian subtypes. The level of differences in the genome of strains of the European subtype, depending on the region and the source of isolation, was analyzed. No relationship was found between the level of homology of nucleotide sequences of TBEV strains of the European subtype and the source of isolation. The proposed models for the evolution of TBE are described. The area of TBE of the European subtype in Eurasia is analyzed. The maps of the geographical distribution of the European subtype are presented. It shows the European subtype TBE is found in 14 regions of Russia. TBE of this subtype, as a rule, causes a disease with a milder course in comparison with TBE caused by a virus of the Far Eastern or Siberian subtypes. An analysis of the main vectors and reservoir hosts of the European subtype TBEV in Europe and in Siberia has been carried out. It is emphasized that in Eurasia the European TBEV circulates in territories that differ significantly in climatic conditions, relief, landscape, and characteristics of biotopes. However, analysis of scientific literature data showed that, despite these differences, it has a high degree of genome stability.

Ulcerative colitis is a chronic inflammatory bowel disease with unclear etiology. An insufficient amount of data on the etiopathogenetic mechanisms of the disease creates opportunities to research them at the cellular level, including the membrane level. Since the functional state of the cytoplasmic membrane largely depends on protein-lipid interactions, we studied the effect of the proportional ratio of three proteins (glucose transporter, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and glutathione-S-transferase (GST)) on the level of phosphatidylethanolamine and phosphatidylcholine in the erythrocyte membrane of patients with ulcerative colitis during an acute attack. The study involved 51 patients with ulcerative colitis during the acute attack and 26 clinically healthy individuals. The groups are comparable by gender and age to study the proteins of the cytoplasmic membrane, Laemmli electrophoresis technique in polyacrylamide gel was used, followed by an assessment of the intensity of protein bands staining on electropherograms. Phospholipid fractions were obtained using thin-layer chromatography and their content was assessed using the Mathcad 2001 Professional system. Statistical processing was carried out by the program Statistica 10.0 for Windows. Changes of phosphatidylcholine and phosphatidylethanolcholine levels in patients and healthy individuals are not of the same type and are interrelated with changes in the proportion of membrane proteins of the glucose transporter, GAPDH and GST. The proportions of proteins that affect the level of phospholipids have calculated. In patients with ulcerative colitis, a decrease in the level of the studied membrane lipids have revealed in comparison with the clinically healthy group, in addition, an increase in the proportion of the glucose transporter and a decrease in the proportion of GST have noted. In addition, the relationship between an increase in the level of the cytoplasmic membrane phospholipids in ulcerative colitis and a change in the proportion of GAFDH in a smaller direction, which slows down the process of glucose oxidation, was determined. The obtained data confirm the strengthening of the processes of antioxidant protection and the increased need for energy supply of the cell membrane in patients with ulcerative colitis during an acute attack.

The trigeminal nerve is a mixed fifth cranial nerve, consisting of motor and sensory components. The sensitive component receives somesthetic information from the skin and mucous membranes of the face into the central nervous system, and the motor component is responsible for the innervation of chewing muscles. One of the manifestations of the pathology of the trigeminal nerve is pain syndrome. Trigeminal neuralgia occupies the main place among neurogenic pain syndrome in the face, is characterized by а severe course and the absence of sufficiently effective methods of treatment. According to the World Health Organization (WHO), the prevalence of trigeminal neuralgia in different countries is 2–5 cases per 100 thousand people per year. Trigeminal neuralgia is classified into 3 etiologic categories. Idiopathic trigeminal neuralgia occurs without apparent cause. Classical trigeminal neuralgia is caused by vascular compression of the trigeminal nerve root. Secondary trigeminal neuralgia is the consequence of a major neurologic disease, e. g., a tumor of the cеrеbеllоpоntine angle or multiple sclerosis. Today, there are many different options for the surgical treatment of trigeminal neuralgia. microvascular decompression of the root, radiosurgical destruction of the Gasser’s node, radiofrequency destruction, glycerol rhizotomy, balloon microcompression are considered the main effective and proven surgical methods for treating trigeminal neuralgia. But the questions of diagnosing the cause of the disease and choosing an adequate surgical method for treating therapeutically resistant trigeminal neuralgia for a particular patient remain open. The development of surgical methods begins from ancient times to the present day. The main stages in the development of neurosurgical treatment methods are presented. The following surgical techniques are described: open method – microvascular decompression, and closed percutaneous destructive methods – radiofrequency destruction, glycerol rhizotomy, balloon compression, radiosurgery, cryodestruction, laser destruction, botulinum toxin injections.

Introduction. Cerebral salt-wasting syndrome and diabetes insipidus are serious complications of craniocerebral injury and spinal cord injuries. Each of the syndromes in some cases causes a life-threatening condition. This determines the importance of timely diagnosis and emergency intensive care measures. In the literature, there are only single descriptions of combinations of these symptoms in one patient.
Clinical case report. A victim with craniocerebral injury and cervical spinal cord injury underwent, according to emergency indications, emptying and drainage of a tense subgaleal hematoma of the fronto-parieto-occipital region, spinal cord decompression, and stabilization of the spine. Postoperative follow-up and intensive care: on the 1st day the rate of diuresis was 2.5 mL/kg/h, blood glucose level – 14.18 mmol/L, and sodium level – 148–158 mmol/L. The patient was diagnosed with diabetes insipidus, and a therapy with desmopressin at a dose of 0.6 mg/day, restoration of fluid volume with hypotonic solutions, and correction of hyperglycemia was started. On the 4th day blood sodium level was 133 mmol/L, and blood glucose level – 8.67 mmol/L. On the 5th day, hyponatremia of 126–115 mmol/L was noted with a diuresis rate of 4 mL/kg/h and glicemya level of 7.86 mmol/L. The development of cerebral salt-wasting syndrome was diagnosed, and the infusion of hydrocortisone 400 mg/day and of 10% NaCl solution was started. On the 6th day glucose level returned to normal. On the 9th day of follow-up, an increase in the volume of diuresis was again observed, and desmopressin therapy was continued. Stable normalization of water-electrolyte balance, urine output, and glucose levels were observed on the 16th day of follow-up.
Conclusion. Monitoring of fluid balance and electrolyte composition of blood serum, and adequate replacement therapy were the conditions for successful treatment of a rare combination of diabetes insipidus and cerebral salt-wasting syndrome in patients with concomitant craniocerebral and spinal cord injuries.

The identification of the PD-1 receptor by Tasuku Honjo and CTLA-4 by James Ellison marked the beginning of the study of new regulatory pathways activating the immune response. The term “immune checkpoints” was introduced to denote the system of inhibitory mechanisms that include these proteins. The review presents the literature data on the molecular characteristics of the membrane protein PD-1 (programmed cell death 1 receptor) and its role in the regulation of immunity. We consider the PD-1 pathways used of by tumor cells to escape the immune response. The discovery of immune checkpoints made it possible to develop a new type of targeting therapy for cancer. The review presents the results of clinical trials of drugs that block the interaction between the PD-1 and its ligands in various types of cancer. These drugs include nivolumab, pembrolizumab, and avelumab. Studies of these drugs efficacy in patients with various types of cancer localization were conducted within the CheckMate, KEYNOTE and JAVELIN Solid Tumor programs, with some research being in progress. We analyze the results of studying the clinical efficacy of the drugs in patients with melanoma, lung cancer, renal cell cancer, colorectal cancer, classical Hodgkin’s lymphoma, Merkel carcinoma and stomach cancer. Both positive and inconclusive results in the treatment of patients are noted. These data made it possible to identify promising directions for the use of the drugs in certain localizations of the malignant process, as well as to determine the dose and time of their use to obtain an objective positive response to treatment.

Background. The diet of adolescents is an important factor in their future health. The diet is formed under the influence of biological, personal, family, socio-economic, environmental, and cultural factors.
The aim: to study the diet of adolescents in rural areas of Buryatia and compare the dietary intake of the Russian and Buryat ethnic groups.
Materials and methods. The study included 92 rural adolescents 11–17 years old (44 boys, 48 girls); 49 of them were Buryats, 43 – Russians. Dietary intake was assessed by the food record method. The intake of energy, macronutrients (proteins, fats and carbohydrates) and micronutrients (major groups of vitamins and trace elements) of the diet was determined. The values obtained were compared with references to daily energy and nutrient intake, and between groups of adolescents of different ethnicity.
Results. The diets of rural adolescents were not balanced. Only 7.6 % of adolescents include fish in their diet. Milk and dairy products are consumed by 38 % of the respondents. Daily energy intake was significantly lower the recommended guidelines. The diet is characterized by a deficiency of vitamins of groups A, C, and D, group B (with the exception of cobalamin), niacin, biotin, essential trace elements (calcium, phosphorus, iodine), high sodium intake. A significant deficiency of dietary fiber has been noted. The Buryats showed a shift in the ratio of proteins, fats and carbohydrates in the diet towards carbohydrates (1 : 1.2 : 5.3).
Conclusion. The results indicate significant disturbances in the composition of the diet in rural adolescents in Buryatia, more pronounced in the Asian subgroup. This can be a rationale for the development of targeted nutrition monitoring programs aimed at preserving the health of the youth.

Background. Harmful environmental factors and negative social trends have an adverse effect on the adaptive resources of the child’s body, which in combination reduces the health index in the child population. An ambiguous epidemiological situation, an increase in morbidity rates in children, a variety of clinical manifestations of Epstein – Barr viral infection, recurrent respiratory diseases, adenovirus infection complicate their differential diagnosis in the early stages. In this regard, the assessment of risk factors and early prognosis of the development of primary form of Epstein – Barr viral infection (EBVI), recurrent respiratory diseases (RRD), adenovirus infection (ADVI) in children is an urgent task.
The aim: to study the significance of risk factors influencing the development of diseases with lymphoproliferative syndrome in children.
Materials and methods. Clinical and laboratory examination and analysis of case histories of 336 children and adolescents held with diseases with lymphoproliferative syndrome. Data from 30 apparently healthy children and adolescents of the same age were used as a comparison group. The Bayesian method with sequential Wald analysis was used to assess risk factors. ROC-analysis was used to check the adequacy of the forecasting models. The quality of the built models was evaluated by their sensitivity and specificity.
Results. It has been established that predictors of diseases with lymphoproliferative syndrome in children are intrauterine fetal hypoxia, low or, on the contrary, high birth weight, neonatal jaundice, low Apgar score, as well as maternal factors (somatic pathology and SARS during pregnancy, gestosis, gestational anemias, young or mature age of the pregnant women). Additional predictors of the development of this pathology can be considered a decrease in the indicator of the cell-phagocytic potential to 337.1 ± 2.3 CU, a decrease in the immune-lymphocytic potential to 237.0 ± 8.2 CU, an increase in the load-erythrocyte coefficient to 0.67 ± 0.03 CU and a decrease in the leukocyte index of intoxication to 0.40 ± 0.05 CU.
Conclusion. The combination of clinical and anamnestic factors with indicators of general reactive potential increases the integral general informative value of the prognostic model. The accounting by specialists of the general medical and preventive network of the identified predictors of the development of diseases with lymphoproliferative syndrome will contribute to the timely diagnosis of the primary form of Epstein – Barr viral infection, recurrent respiratory diseases and adenovirus infection in children.

Metabolic syndrome (MS) is a very serious pathological condition that occurs in the clinical practice of doctors of various specialties. Often, the presence of MS aggravates the course of comorbidities, while various diseases can serve as a risk factor for its development. The significant prevalence of MS determines the need for its early diagnosis for timely correction and prevention of its long-term complications.
The aim. To systematize data on the prevalence of metabolic syndrome in various countries and populations and to discuss the most frequently used diagnostic criteria, including racially and ethnically differentiated ones.
Materials and method. A literary search was carried out using scientific databases: eLIBRARY, PubMed.NCBI, CyberLeninka, the official website of IDF for the period from 1999 to 2020.
Results. It was found that despite different diagnostic criteria used for MS, its prevalence in many countries is comparable (10–30 %) but differs in different populations. Thus, MS occurs more often in Caucasians than among Asians, and its prevalence is significantly higher in the newcomer vs the indigenous population. Nevertheless, a comparative analysis of the frequency of MS is difficult due to the use of research results based on different approaches to its diagnosis in the literature presented in the literature. Although the analysis of literature data indicates the existence of specific features of the prevalence of MS in different populations, the differentiated approaches to detecting MS depending on the race of patients, which are necessary for many countries, have not yet been sufficiently developed.

Background. Head and neck squamous cell carcinoma are the sixth most common cancer in prevalence rate. Early diagnosis significantly reduces morbidity and mortality. Autofluorescence facilitates diagnosis the disease at the early stages, but it depends on the doctor’s skill in interpreting images.
The aim of the study: to analyze the results of reading autofluorescence images of the oral mucosa by dentists.
Materials and methods. The results of reading 10 autofluorescence images of potentially malignant diseases of the oral mucosa and 10 images of benign lesions and conditions were evaluated. The study involved 308 dentists. The assessment of the ability to recognize autofluorescence images was carried out with respect to gender, age, length of service, qualification category, academic degree, position of the head of the department.
Results. On the average, dentists correctly differentiated the results of visualization of potentially malignant diseases of the oral mucosa in 3.85 ± 2.47 cases, benign lesions together with other benign conditions – in 4.56 ± 2.47 cases. Images of benign lesions and conditions were identified by dentists better than images of potentially malignant diseases of the oral mucosa (t = –17.0; p < 0.001). There is a direct correlation between the correct differentiation of visualization of potentially malignant diseases of the oral mucosa with the correct interpretation of benign lesions and conditions (r = 0.956; p < 0.001). The interpretation of potentially malignant diseases of the oral mucosa is not related to gender (t = –1.62; p = 0.306), work experience (r = –0.002; p = 0.977), department head (t = –0.11; p = 0.910), qualification category (t = –0.50; p = 0.574), academic degree (t = –0.34; p = 0.731).
Conclusion. Dentists cannot recognize diseases of the oral mucosa well in autofluorescence images. The recognition skill is not related to general professional development.

Despite of intensive work on improving endoprosthetic replacement constructions, using minimally invasive techniques, developing methods of prevention for and treatment of periprosthetic joint infection, relapse of infection process can reach up to 52 % after treatment.
The aim of the study: to show the importance of identifying the risks of development and recurrence of periprosthetic infection after implantation of a knee joint endoprosthesis. A clinical case of the development of a deep periprosthetic infection in a patient after primary knee replacement and successful treatment of the resulting complication was demonstrated. The analysis of this case of an infectious complication using the proposed prognosis for the development of periprosthetic infection showed that before surgical treatment of the patient, the risk of an infectious process was not assessed, and appropriate preventive and therapeutic measures were not carried out.
Materials and methods. In the treatment of developed periprosthetic infection of the knee joint, the author’s algorithm for choosing surgical tactics was used, which allowed to determine the high risk of recurrence of periprosthetic infection, evaluate additional criteria and choose the optimal type of surgical intervention – two-stage revision endoprosthetic, which allowed to stop the infectious process.
New was the use of the proposed prognosis for the development of periprosthetic infection and the algorithm for choosing surgical tactics for periprosthetic infection, which make it possible to determine the necessary preventive measures to reduce the risk of an infectious complication and to apply the optimal type of surgical intervention to relieve periprosthetic knee infection.

Radial fracture is the most common trauma to the musculoskeletal system and accounts for 50 % of traumatic injuries to the bones of the upper limb. Disability in patients with fractures of the forearm bones ranges from 6 to 8 months, so the choice of the most effective method of treatment is very relevant. Currently, an important point is the tendency of optimizing the transosseous method by eliminating the disadvantages and looking for new advantages of external fixation. Bone fracture and associated surgical intervention are always accompanied by varying degrees of changes in the links of the central nervous system, hemodynamics and metabolism. In order to study the bioelectrical activity of the brain in 47 patients with a fracture of the radial diaphysis treated in the Traumatology Department of the Irkutsk Scientific Centre of Surgery and Traumatology, in the pre- and postoperative period we compared EEG indicators of two variants of the layout of the external fixation apparatus (EF): wire and rod. Analysis of the rhythms of bioelectrical activity of the brain in both groups in the preoperative period revealed a normal zonal distribution with the dominance of the alpha rhythm on the EEG, which generally reflects a rather high degree of organization of neuroactivity and indicates the stability of cerebral homeostasis. At the same time, in the group of patients with a wire-mounted EF device in the postoperative period, EEG indices significantly differed from the values of the norm and ndicators in the group with a rod-shaped arrangement. A decrease in the amplitude of alpha and beta rhythms was noted, as well as a shift in the frequency of bioelectric activity towards slow waves, which is a sign characteristic of discirculatory encephalopathy. An EEG study using the method of transosseous osteosynthesis with EF devise of a rod assembly showed its greater efficiency compared to the use of an EF device of a wire assembly during treatment and rehabilitation. Thus, the study of the bioelectric activity of the brain is a reliable method for assessing its functional state after an injury, as well as the effectiveness of the treatment.

The literature review provides data on tuberculosis of the urethra in men. This disease is rarely recorded, as a rule, at the stage of formation of the urethral stricture, which can develop many years after the onset of the disease. Urethral tuberculosis is usually secondary to other localizations of extrapulmonary tuberculosis, such as tuberculosis of the prostate, penis, kidney, and bladder, but there are also isolated forms of this disease. The most common symptoms of urethral tuberculosis are the presence of strictures, skin-urethral and recto-prostatic fistulas, and purulent urethritis. Almost always, with this disease, conservative specific therapy was carried out, which in some cases made it possible to completely eliminate the symptoms and ensure the patient’s clinical recovery. Tuberculous urethral strictures are operated on according to generally accepted rules, but there is no single algorithm for the surgical treatment of strictures of this etiology, often limiting itself only to urine diversion or urethral dilation. Of the urethroplasty, the most commonly used end-to-end urethral anastomosis. In our opinion, a promising direction is the use of various grafts for the surgical treatment of this disease.

Inguinal hernias (IH) are widespread in the human population and occur in 27–43 % of men and 3–6 % of women. Many risk factors for IH have been overestimated in the last decade: male gender is considered the leading factor (the ratio between men and women is approximately 1:7), less significant factors are heredity (most significant for women), physical activity (more significant for men), age (peak prevalence of IH occurs at 5 years and 70–80 years), congenital or acquired connective tissue dysplasia, history of prostatectomy, low body mass index.
Hernioplasty with the use of synthetic mesh prostheses remains the most popular technique for surgical correction of IH. Performing non-prosthetic hernioplasty is only recommended if mesh prostheses are not available, for example in poor countries. In open hernioplasty using mesh prostheses, different methods are used today: Plug & Patch, Prolene Hernia System, Parietene Progrip, sutureless plastic according to Trabucco, Stoppa, preperitoneal techniques TIPP (trans-inguinal pre-peritoneal), TREPP (transrectus pre-peritoneal), TEP (total extraperitoneal), however, none of them showed significant advantages over the gold standard of open hernioplasty – tensionfree repair according to Liechtenstein.
Laparoscopic IH correction is represented by the TAPP (transabdominal preperitoneal) technique, performed through the abdominal cavity, and TEP (total extraperitoneal) – extraperitoneal prosthetic hernioplasty. None of them has a significant advantage in the treatment of IH; therefore, when choosing a treatment method, the surgeon should be guided by the cost of the operation and the level of proficiency in one or another hernioplasty technique.

 Surgical treatment of patients with postoperative ventral hernias is one of the most pressing problems in herniology. Verification of the diagnosis of postoperative ventral hernia is usually not difficult. At the same time, there may be difficulties in diagnosis associated with determining the true size of the hernia orifices, the contents of the hernial sac. These moments are  determined by various factors: the location of the hernia on the anterior abdominal wall, the age, sex of the patient, as well as anamnesis of hernia and the volume of surgery previously performed. One of the very rare situations in external abdominal hernias is the situation when the content of  the hernial sac is the part of the parenchymal organ, the tumor process, as well as foreign bodies. The study presents the observation materials of three patients admitted for diagnosis and treatment to the surgical hospital clinics of Irkutsk State Medical University. When examined and treated, it was found that in one case the content of the hernia sac included a part of the left lobe of the liver, in another observation, the inguinal hernia sac contained metastatic carcinoma, in the third case – a foreign body was found. All patients underwent surgery (hernioplasty, hernioplasty). Diagnosis of hernia of the anterior abdominal wall was confirmed. A literary search was made for rare clinical examples in herniology. In the world literature, there are only eight observations when the content of the hernia sac was a part of the lobe of the liver; the presence of metastatic carcinoma and a free foreign body we found as single observations described by known specialists in herniology. 

It is known that the circadian rhythm of melatonin production depends on the intensity of illumination. Violation of the light regime leads to suppression of melatonin synthesis and the development of desynchronosis, which increases the risk of developing a number of pathologies. In this regard, it is relevant to search for opportunities to restore disturbed circadian rhythms and, especially, to correct immune dysfunctions that occur in these situations.
The aim of this study was to examine the effect of a complex of melatonin, aluminum oxide and polymethylsiloxane on the lymphocytes of the spleen of mice kept under round-the-clock lighting.
Materials and methods. Mice of the C57Bl/6J line were kept under round-the-clock lighting for 14 days, against which they were intragastrically injected with distilled water, aluminum oxide with polydimethylsiloxane, melatonin and a complex of melatonin, aluminum oxide and polymethylsiloxane (a new drug developed by the Research Institute of Clinical and Experimental Lymphology – Branch of the Federal Research Center Institute of Cytology and Genetics SB RAS; Patent of Russian Federation No. 2577580, 2016), represented by a complex of porous material (aluminum oxide with polydimethylsiloxane) and melatonin, immobilized in the pores, from which it is gradually released in a liquid medium. Intact animals kept under the light regime of ST 12/12 and under round-the-clock lighting served as a control. Immunophenotyping of spleen B- and T-lymphocytes was performed on a flow cytofluorimeter with monoclonal antibodies APC CD3 and FITC CD19. For studying the distribution of cells by stages of the cell cycle in splenocytes, the amount of intracellular DNA was measured by the level of inclusion of propidium iodide.
Results. Flow cytometry of the distribution of B- and T-lymphocytes of the spleen in male mice of the C57Bl/6J line kept under round-the-clock lighting conditions (KO 24/0 h) revealed a decrease in the percentage of B-lymphocytes and an increase in the number of T-lymphocytes, compared with animals kept under standard lighting conditions (the light/dark photoperiod – 14/10 hours). The ratio of CD19+/CD3+ lymphocytes of the spleen in mice under the conditions of KO significantly decreases (1.5 times) compared to intact animals (p ≤ 0.001). The administration of pure and modified melatonin (Complex M) to animals kept under round-the-clock lighting conditions has an equally pronounced normalizing effect on the cellular composition of B- (CD19) and T- (CD3) lymphocytes of the spleen, bringing the values of the studied parameters to the control values of the intact animals (p ≤ 0.001) Round-the-clock lighting affects the proliferative potential of splenocytes, reducing the number of cells in the G2/M phase, compared with animals treated with melatonin (p ≤ 0.050). The introduction of melatonin leads to an increase in the percentage of cells in the G2/M phase relative to the placebo group (p ≤ 0.050). In the group of mice treated with Complex M, the greatest increase in cells at the S + G2/M phases and the highest percentage of cells at the G2/M phase were revealed compared to the placebo control group (p ≤ 0.050).
Conclusion. The complex of melatonin, aluminum oxide and polymethylsiloxane has additional immunotropic properties in relation to the modifier molecule, which, apparently, are due to the joint immunostimulating effect of melatonin and the lymphostimulating effect of the sorbent. Melatonin in the composition of the complex shows its properties more stably.

Background. Due to the growing light pollution and the development of new territories, including northern ones, the search for drugs that increase the adaptive capacity of the organism is promising.
The aim. We studied the effects of the exogenous melatonin (100 µg/day/animal) on antioxidant status of liver and small intestine in Syrian hamsters (Mesocricetus auratus) in the light conditions of North-West of Russia (Petrozavodsk, northern lighting – NL).
Materials and methods. Female hamsters were exposed to a 12/12 light/dark cycle (LD; n = 12) or NL for 3 months. In NL light conditions hamsters were divided into two groups: NL-control (received placebo; n = 12) and NL-mel (received melatonin; n = 12). The study was conducted from the period of the summer solstice – June 25 (NL: 19.36/4.24) to September 25 (NL: 12/12) (autumn equinox).
Results. Animals were kept in the NL conditions had decreased the levels of GSH and activities of antioxidant enzymes (superoxide dismutase (SOD) and catalase) at initial stage of experiment as well as increased TBA reactive substances (TBARS) level at the beginning and after a month of the experiment in the liver in comparison to control (LD). It was observed that in the small intestine the activities of SOD and the levels of GSH (initial and intermediate stages) and TBARS (end of the experiment) were significantly higher in NL in comparison to LD. Liver and small intestine TBARS concentrations after one and three months of the experiment were decreased in NL-mel in comparison to NL-control.
Conclusion. The results of the study indicate the sensitivity of the antioxidant defense system in the tissues of the liver and small intestine of Syrian hamster to the photoperiod and exogenous melatonin. The present study revealed that exogenous melatonin was able to reduce the level of TBARS and increase the activity of SOD and CAT in the light conditions of North-West of Russia.

Background. Currently, the COVID-19 pandemic in the world and in Russia remains the main event. In this regard, the study of the manifestations of the epidemic process of the new coronavirus infection COVID-19 and the patterns of its development are an urgent area of research. In the fight against this viral disease, an important role is assigned to the study of the development of population immunity to the SARSCoV-2 virus, which will make it possible to assess the dynamics of seroprevalence and the formation of post-infectious humoral immunity, forecasting the development of the epidemiological situation, elucidating the characteristics of the epidemic process, and will also contribute to planning activities for specific and non-specific prevention of the disease.
The aim: to determine the dynamics of population immunity to SARS-CoV-2 among the population of the Irkutsk region during the COVID-19 pandemic.
Materials and methods. As a part of the Rospotrebnadzor project of assessing population immunity to SARS-CoV-2 in the population of the Russian Federation, the research has being conducted among the population of the Irkutsk region in the periods from June 23, 2020 to July 19, 2020 (Stage 1), from September 16, 2020 to September 25, 2020 (Stage 2), from December 7, 2020 to December 18, 2020 (Stage 3) and from March 8, 2021 to March 14, 2021(Stage 4), taking into account the reacted one recommended by the WHO. The content of antibodies to SARS-CoV-2 was determined by ELISA using a set of tests for human serum or plasma for specific immunoglobulins of class G to the proteins of the SARS-CoV-2 coronavirus.
The results. The research of the humoral immunity of volunteers shows that during the period of an epidemic rise in the incidence of COVID-19 in the Irkutsk region, a low level of seroprevalence was formed (Stage 1 – 5.8 ± 0.5 %, Stage 2 – 12.1 ± 0.7 %), and in conditions of a long-term maximum increase in the incidence rate – 25.9 ± 1.0 % (Stage 3) and 46.2 ± 1.2 % (Stage 4). A significant proportion (Stage 1 – 82.2 ± 3.2 %, Stage 2 – 86.1 ± 2.3 %) of asymptomatic forms of infection characterizes the high intensity of the latently developing epidemic process in the first two stages. High levels of IgG in reconvalescents of COVID-19 persisted for an average of 3 to 5 months.
Conclusion. The results of assessing the population immunity to the SARS-CoV-2 virus in the population of the Irkutsk region indicate that the seroprevalence level at Stage 4 of the research was 46.2 %. After the disease, on average, 49.5 % of persons did not detect antibodies. The results obtained should be taken into account when organizing preventive measures, including vaccination, and predicting morbidity.