Being the core of the scientific community, scientific schools play a special role in the formation of civil society. In addition to purely subject content, a scientific school is essentially an effective model of education as a transmitter of cultural norms and values of the scientific community from the older to the younger generation.

The scientific school “Physiological and Medical Aspects of Health of Various Population Groups in the Sakha Republic (Yakutia)” is an example of organizing interdisciplinary research devoted to the problem of human health in the extreme conditions of the North and its interaction with the ecology of the environment. The article is dedicated to the founder of the scientific school, Academician of the Academy of Sciences of the Sakha Republic (Yakutia), Doctor of Medical Sciences, Professor Palmira Georgievna Petrova.

Diamond-Blackfan anemia (DBA) is a rare form of congenital red cell aplasia of hematopoiesis in infants and children, characterized by suppression of erythropoiesis and congenital malformations. The article presents an observation of a child with DBA. The girl was born with severe anemia. The diagnosis was established at the age of 3 months, genetically confirmed at 2 years. Since her birth, she had been receiving monthly transfusion therapy with red blood cells. Treatment with prednisolone, L-leucine was carried out without effect, the child remained transfusion-dependent. The only curative method for this disease is hematopoietic stem cell transplantation (HSCT). With a 14-year-old sibling not suitable, there was no other suitable related donor. By the age of 15, the child had developed serious complications caused by post-transfusion iron overload of the liver (grade 4), myocardium, pituitary gland with the development of liver and heart failure; endocrine disorders in the form of hypopituitarism, primary and secondary hypothyroidism, increased fasting glycemia. In addition, the girl has chronic viral hepatitis C. In order to remove excess iron from the body, the patient has been receiving chelation therapy since the age of 8.

The accumulation of iron in organs leads to irreversible dysfunction, reducing the life expectancy of patients with DBA, so early initiation of chelation therapy is necessary.

Compared to the year of the COVID-19 (COronaVIrus Disease 2019) pandemic outbreak, the year 2023 witnessed an increased number of cases when patients with new coronavirus infection were transferred from non-infectious hospitals to infectious ones, which led to the assumption of the transition of SARS-CoV-2 (Severe acute respiratory syndrome-related coronavirus 2) infection to the category of nosocomial infections.

Objective of the study: to study the dynamics of changes in the frequency of hospitalization of patients with a confirmed diagnosis of COVID-19 in the Irkutsk Regional Infectious Diseases Clinical Hospital from noninfectious hospitals to confirm the hypothesis about transition of the new coronavirus infection to the category of nosocomial infections.

Materials and methods of the study. A retrospective analysis of 510 inpatient observation medical records of patients with a confirmed diagnosis of COVID-19 who were admitted to the Irkutsk Regional Clinical Institution and were treated in 2020 (250 medical records) and 2023 (260 medical records) was carried out. Statistical processing of the study results was carried out using the data analysis package in Microsoft Excel and online calculators on the website https://medstatistic.ru/index.php. Statistical significance was assessed at p≤0.05.

Conclusion. The results obtained showed that over time the new coronavirus infection acquires features of nosocomial infections. This study demonstrates an increased average age of patients, as well as an increase in the number of patients with different comorbidities with a simultaneous shorter staying at hospital due to a decreased proportion of severely ill patients. In both the periods compared, women predominated among patients.

Meningococcal infection (MI) is a current disease with a wide range of clinical manifestations and an aggressive course. The clinical picture of meningococcal infection is characterized by polymorphism of manifestations from asymptomatic to extremely severe forms, leading to death within a few hours. The risk group for MI are children under 5 years of age. The GFMI can be caused by 6 serogroups: A, B, C, W, X and Y. Serotype W had not been registered in the Sakha Republic (Yakutia) until recently. With the MI caused by Neisseria meningitidis W, a number of authors note the polymorphism of the clinical picture of the generalized form of meningococcal infection. The presence of various atypical manifestations is characteristic. The article presents three clinical cases of patients with generalized meningococcal infection caused by Neisseria meningitidis, two of whom had the disease caused by serogroup W. Three young patients with similar clinical picture had no contacts confirmed by epidemiological investigation. All three had an atypical onset of the disease, with gastrointestinal syndrome. Eventually, all developed the clinical picture of severe meningoencephalitis. The peculiarity of these cases is isolated meningoencephalitis, without meningococcemia, which is the least common among generalized forms of meningococcal infection. Two patients were diagnosed with mixed infection with Epstein-Barr virus. One patient developed arthritis, according to the classification, related to rare forms of MI. In all patients, the outcome of the disease was sensorineural hearing loss.

This research says that lichen ruber planus (LRP) has a wide range of clinical manifestations in the oral cavity, where the main morphological element of the lesion is papular rashes accompanied by inflammatory and proliferative processes. At the same time, the etiological factors and pathogenetic mechanisms of development are currently not fully understood. In many pathological conditions of the body, oxidative stress plays a leading role in the mechanism of damage to the structure of cell membranes, violation of their permeability, which is associated with increased production of reactive oxygen species, which have a pronounced reactive effect. For the state of oxidative stress (OS), first of all, it is typical to have an imbalance in the ratio of the pro- and antioxidant systems in the direction of strengthening the former, which possibly contributes to the development of inflammatory and destructive lesions in the COPR with CPL. The aim of the study was to study the activity of free radical processes in the blood serum of patients with CPL COPR for a selective approach to the appointment of corrective therapy. Materials and methods of research. The study of biochemiluminescence parameters was carried out in 66 recipients with CPL SOPR, age group from 35 to 65 years and a control group that included 33 people of similar age, without clinical manifestations of diseases of SOPR. The intensity of free radical processes in blood serum was assessed by chemiluminescence (CML) using the LS 50B “PERKIN ELMER” spectrometer. Spontaneous, Fe2+-induced and H2O2-initiated chemiluminescence in the presence of luminol was recorded. The obtained data were displayed in relative units. Results. The obtained results by the method of chemiluminescence (CML) in serum in recipients with clinical LRP manifestations in the oral cavity determine the dynamic characteristic of intensification of free-radical processes. At the same time, actual data on the weakening of the antioxidant protection systems barrier (Ssp, h, Sind-1, Slum, H and Sind-2) were revealed compared to similar data of the control group. Discussion. CML indicators reflect an increase in the production of free radicals of a lipid nature and a weakening of the antioxidant barrier in individuals with CPL COPR, which indicates the development of OS in the body as a whole. Conclusion. Taking into account the development of the state of systemic OS in CPL COPR, it is justified to correct it in a timely manner by including antioxidants in the general treatment complex to reduce the duration of manifestations of lesions and to provide a positive effect of the therapy.

The relevance of studying viral hepatitis D is associated with the increasing prevalence of the disease worldwide and an aggressive clinical course compared to other parenteral hepatitis. The Sakha Republic (Yakutia) is a territory of the Russian Federation with a high level of prevalence of hepatitis D virus among the indigenous population. While effective antiviral therapy does not cover all patients in need, chronic HDV-infection leads to the rapid formation of disabling forms of liver disease. The aim of the work was to study the clinical and laboratory features of the course of HDV-infection among the indigenous population of the Sakha Republic (Yakutia) for further use of data in the development of a prognostic model to identify the risk of severe course such as HD-cirrhosis of the liver. We examined 157 patients at different stages of the disease: 71 men and 86 women, aged between 22 and 77 years, with the average age at 48 ± 10.5 years. It was found that 30.6 % of chronic hepatitis proceeds without severe liver fibrosis; 56.1 % of patients have cirrhosis; and 13.3 % have hepatocarcinoma. Liver cirrhosis develops on average 6.8 years after detection of anti-HDV. Epidemiologically significant risk factors for severe course are a history of acute hepatitis B (p=0.038) and intrafamilial contact (p=0.02). The study of the clinical and laboratory picture showed an increase in the severity of the patients’ condition with the formation of cirrhosis and liver cancer. Mixed replication of HBV/HDV was significantly more often (p<0.001) observed in patients with cirrhosis and HCC. The overall mortality rate among patients was 17.8 % and the main cause of death was progressive liver failure.

Conclusion: The territory of the Sakha Republic (Yakutia) is unfavorable in terms of the prevalence of chronic forms of HDV infection. The analysis confirmed a high risk of developing severe fibrosis among the indigenous population in 69 %, which requires strengthening measures for the early diagnosis of complications, as well as increasing the coverage of antiviral treatment for patients in the region.

The article presents data on the prevalence of enterovirus meningitis in the Far Eastern Federal District for the period from 2010 to 2023. Enterovirus meningitis was registered in all territories of the Far Eastern Federal District. The maximum incidence rates were detected in Khabarovsk Krai. The maximum indicators for Khabarovsk Krai, statistically exceeding all subjects of the Far Eastern Federal District, are probably the result of effective laboratory diagnostics, and not the presence of additional risk factors for the development of the epidemic process. Sakhalin Oblast ranked second, followed by Jewish Autonomous Oblast. In addition, clinical manifestations of enterovirus infection in the form of meningitis were steadily formed only in Primorsky Krai and Amur Oblast. These subjects can be considered as endemic for enterovirus infection, clinically manifested by meningitis. There are no grounds to classify Chukotka Autonomous Okrug, Magadan Oblast, Kamchatka Krai and the Sakha Republic as endemic for enterovirus infection manifested by meningitis. In some years, the proportion of enterovirus meningitis ranged from 8 to 58 % of enterovirus infection. Enteroviruses Echo (53.2 %), Coxsackie A (29.8 %) and Coxsackie B (17 %) were isolated from patients. No statistical association of enterovirus meningitis with certain serotypes of the pathogen was revealed. The main age groups of patients with enterovirus meningitis in the period from 2017 to 2022 were children of 3-6 years of age and 7-14-year-old schoolchildren. In the structure of computer patients, they accounted for 28.7-45.2 % and 39.3-62.6 %, respectively. A small proportion of cases (up to 3.4 %) occurred in children under the age of one year. From 3.1 to 14.2 % of the cases were represented by 1-2-year-old children. Persons aged 15-17 years accounted for 0.1-8.3 % of cases in the age structure of computer disease. The long-term dynamics of the incidence of enterovirus meningitis in endemic territories was characterized by the presence of cyclicity.

Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease within the spectrum of motor neuron disorders, selectively targeting central and peripheral motor neurons in the brain and spinal cord, with highly variable clinical manifestations. One rare form of ALS is progressive muscular atrophy (PMA), primarily characterized by the selective involvement of peripheral motor neurons and a slower, less aggressive progression compared to classical ALS. Currently, the scientific community lacks consensus on whether PMA should be classified as a distinct nosological entity or as a subtype of ALS.

Recent advancements in genetic research have identified that familial and hereditary forms of ALS are most frequently linked to mutations in the SOD1, TARDBP, C9orf72, and FUS genes, among others. Moreover, increasing progress in genetic testing now enables the identification of mutant genes responsible for various phenotypes. Understanding the genetic underpinnings of motor neuron diseases is crucial for elucidating their pathogenesis, which may pave the way for the development of novel diagnostic and therapeutic strategies.

This article presents a clinical case involving a patient with a PMA phenotype associated with the H49R mutation in the SOD1 gene. A comprehensive account of the patient’s anamnesis, clinical presentation, molecular-genetic findings, as well as results from instrumental investigations, including electromyography and magnetic resonance imaging, is provided. The article discusses the potential nosological autonomy of PMA and its association with the H49R mutation, referencing current data from both Russian and international studies. Additionally, the article highlights the challenges of differential diagnosis, particularly in distinguishing PMA from other neurodegenerative diseases with similar clinical profiles.

This case contributes to the expanding knowledge of the heterogeneity of motor neuron diseases and underscores the importance of molecular-genetic testing in predicting disease prognosis and guiding patient management.

An analysis of literary sources characterizes the presence of numerous harmful factors, accompanying professional activities of dentists. The article considers the influence of harmful factors on the health of dentists, which cause the emergence and development of occupational pathological conditions. The main risk factors are psychoemotional professional burnout; stressful situations; constant noise from devices and equipment; prolonged uncomfortable positions of the doctor’s body when providing dental care; frequent contact with harmful substances, affecting the respiratory system and skin; proximity of the “operative field” when working with infected patients. Harmful occupational factors contribute to the development of hearing impairment, neurological and skin diseases, respiratory and musculoskeletal diseases, as well as infectious diseases. The relevance of an integrated approach to reduce the risk of developing occupational somatic pathology is substantiated. The main goal of work in medical and preventive institutions of the dental profile is to create optimal conditions for the work of medical personnel in accordance with the requirements of modern science and occupational health, to increase productivity and maintain strength and health. To date, the prevention of harmful factors in the profession of a dentist is an important aspect of ensuring his health and safety. At the same time, in order to reduce the harmful effect of various working factors in the work of a dentist, it is necessary to observe ergonomic principles of labor organization. In addition, compliance with sanitary and anti-epidemiological rules in the workplace should be combined with the allocation of time for rest and the restoration of the compensatory and adaptive potential of the body. One of the important factors in maintaining the psychological well-being of medical workers and their stress resistance is the prevention of professional emotional burnout of specialists. In this regard, timely training in stress management and psychological support in the team is an extremely important factor. At the same time, it is important to constantly comply with the rules of balanced nutrition. Paying attention to daily exercise and outdoor activities, it is also necessary to undergo timely examination and compliance with sanitary and hygienic rules contribute to the prevention of possible problems.

In the recent years, complications of drug therapy are an important medical problem. Data on adverse drug reactions (ADRs) in older patients were analyzed. The object of the study was notification cards for NR received from medical organizations (MO) of Irkutsk region for a five-year period. The Narangio scale was used to assess the causality (SST) between ADR and LS. Of the 1068 ADR notifications in patients over 60 years of age, 2/3 (705) are presented with ADR notifications in women, 363 (34.0 %) – in men. The presence of background diseases was registered in 940 notifications (88.0 %). There were no gender differences except for a higher incidence of chronic obstructive pulmonary disease in men (7.2 % and 3.5 %, respectively, p < 0.05) and diabetes mellitus in women (14.0 % and 3.5 %, respectively, p < 0.05). ARs for antibacterial agents amounted to 31.8 %, drugs for the treatment of cardiovascular diseases – 10.5 %, cases of therapeutic inefficiency – 5.4 %. The ADR data statement was in line with the recommended form of 76 %. The most common filling defect was incomplete patient information. The validity of the Narango PSS was high. The deadlines for reporting data were observed in 93 %. For effective interaction in the pharmacovigilance system, it is necessary for each MO to constantly inform about the procedure for pharmacovigilance, types of ADRs, the rules for their detection and the timing of data reporting. The work should be supervised by a trained specialist.

The article presents the results of the amino acid composition of urine in children with connective tissue disorders (undifferentiated connective tissue dysplasia syndrome – uCTD) living in the Republic of Sakha (Yakutia). Connective tissue disorders are associated with complex metabolic changes, including amino acid metabolism in children. However, currently available data are contradictory. The aim of this study was a comprehensive assessment of connective tissue disorders, as well as a comparative analysis of the amino acid levels in the urine of healthy children and children with uCTD. Materials and methods. The present study included 524 children who were part of the control group and 1266 children with undifferentiated connective tissue dysplasia syndrome included in the experimental group. The level of amino acids in the urine of 105 children was assessed using gas chromatography. Statistical analysis was performed using the SPSS program, version 22. Results and discussion. It has been established that the levels of amino acids in the urine of children provide information on the existing imbalance, which indicates, among other things, nutritional and metabolic disorders underlying a large number of diseases, including disorders associated with connective tissue. It is concluded that increased excretion of various amino acids in the urine of children with undifferentiated CTD syndrome may be a consequence of impaired protein synthesis due to the absence (or deficiency) of any amino acids in the diet.