Introduction . Employees of medical organizations are a professional risk group for contracting bloodborne infections, which requires constant improvement of preventive measures, including optimization of approaches to the immunoprophylaxis of viral hepatitis B.

Materials and methods . In 2024–2025, the vaccination history and serological screening data of 1,380 medical organization employees for anti-HBs were analyzed. Laboratory tests were performed in the clinical and diagnostic laboratory of the UMMC-Health using enzyme immunoassay (the Vecto HBsAg-antibodies test system). Results . The proportion of people with anti-HBs ≥10 mIU/ml was 81.8 %. In binary logistic regression, prognostic factors affecting antibody concentrations were established: the age of employees, the period since the last vaccine was administered, and the number of vaccine doses ( p < 0.001). For modifiable factors, the linear regression model found that the concentration of anti-HBs decreased by 10.992 mIU/ml each year after immunization ( p < 0.001) and increased by 59.757 mIU/ml with each additional vaccine ( p < 0.001). Among the ROC curves, the model for the number of vaccines with a threshold value at the cut-off point was 4 (AUC = 0.745±0.018; 95 % CI: 0.709–0.781; sensitivity 83.2 %; specificity 57.0 %; p < 0.001).

Conclusion . The study made it possible to determine the prognostic factors affecting post-vaccination immunity to hepatitis B virus in medical workers, which justifies the need for further research to develop an optimal booster immunization strategy, taking into account a comprehensive analysis of the humoral and cellular immune response, clinical and anamnestic data and the general somatic status of staff.

Introduction . Tick-borne encephalitis (TBE) remains one of the most significant natural focal infections in the Russia. High incidence, severe clinical course, and diverse outcomes from full recovery to persistent disability and death underscore the medical and social significance of the problem.

The aim of the study is to analyze the possible causes of high mortality in a number of regions of the Northwestern Federal District (NWFD) and assess the adequacy of existing preventive measures against TBE, as well as propose measures to improve prevention.

Materials and Methods . Data from the state statistical form No. 2 “Information on Infectious and Parasitic Diseases” for 2014–2024, demographic indicators, and annual state reports “On the State of Sanitary and Epidemiological Well-being of the Population” for NWFD territories were used. Epidemiological (descriptive-evaluative and analytical) and statistical methods were applied. Data are presented as absolute and relative values.

Results . TBE incidence in the NWFD ((1.539±0.500) per 100 000 population) consistently exceeds the national average ((1.188±0.281) per 100 000). The case fatality rate was 3.70 % (95.00 % CI 2.63–5.14). The greatest burden of fatal outcomes (45.95 %) falls on Arkhangelsk Region, where vaccination coverage does not exceed 4.00 % and acaricidal treatments cover only 0.001 % of the territory. Vologda Region reported fatalities despite vaccination coverage >11.00 %.

Discussion . Key factors associated with adverse outcomes were identified: insufficient vaccination coverage, extremely low volumes of acaricidal treatments, and poor public awareness.

Conclusion . Reducing morbidity and disability requires mass immunization in endemic territories, scaling up anti-tick treatments, and intensifying public health education.

Introduction : Lymphopenia is one of the main laboratory signs of severe COVID-19 and a poor prognosis. The purpose of this study was to evaluate the content of lymphocyte subpopulations in lung tissue and spleen in patients who died from COVID-19.

Materials and methods . A study was conducted on autopsy material obtained from 17 patients who died from COVID-19. The control group consisted of 11 patients who died from other, non-infectious causes. The quantities of CD3+ lymphocytes and CD4+, CD8+, and CD20+ lymphocyte subpopulations were determined in lung tissue and spleen.

Results . An increase in the number of CD3+, CD4+, and CD8+ positive cells was found in the lungs of patients who died from COVID-19. CD4+ and CD8+ positive cells showed the most pronounced increase, with mean values 561 and 174 times higher than the control group, respectively. In the spleen of patients with COVID-19, a two-fold decrease in the number of CD3+ positive cells was observed compared to the control group. The most pronounced reduction was seen in CD8+ positive cells, whose mean value in COVID-19 patients was 2.8 times lower than in the control group. The median area of the splenic white pulp in patients with COVID-19 was 1.6 times smaller than in the control group.

Conclusion . Patients who died from severe forms of COVID-19 exhibit an accumulation in lung tissue and a depletion in the spleen. The identified reduction in the area of the splenic white pulp in COVID-19 patients indicates the development of immunosuppression.

COVID-19 in children causes significant changes in the immune and coagulation systems, which persist in the post-COVID period, which can lead to the formation of adverse consequences.

Objective of the study was to determine the risk factors for the development of long-term consequences of a new coronavirus infection in children.

Materials and methods . The assessment of the state of the immune and coagulation systems in children in the acute and long-term period, as well as the analysis of the health status of children who have had COVID-19 ( n = 132). Research was conducted to analyze the immune status of children with COVID-19 and their level of protection against vaccinepreventable infections ( n = 60).

Results . During the acute period of COVID-19, children’s immunograms showed an increase in the level of activated T-lymphocytes ( p < 0.001), a decrease in serum IgM and IgG ( p < 0.050), and a high level of CIC ( p < 0.050). In addition, patients over 8 years of age had leukopenia ( p < 0.05), lymphocytosis ( p < 0.05), neutropenia ( p < 0.001), and decreased neutrophil absorption activity ( p < 0.05). In the post-COVID period, there was a reduced level of immunoglobulins M and G, neutropenia, an increased level of activated T-lymphocytes, and a high level of CIC. Evaluation of coagulogram indicators at the debut of NCI showed the presence of reduced platelet aggregation ( p < 0.010), thrombin time ( p < 0.001), increased concentration of fibrinogen and D-dimer ( p < 0.001), euglobulin lysis time and high content of RFMC. After SARS-CoV-2 infection, increased values of fibrinogen, D-dimer, euglobulin lysis time, RFMC remained.

Discussion . The acute period of NCI was characterized by activation of the cellular and phagocytic links, insufficient levels of humoral protection, high levels of circulating immune complexes, and age-related differences. Changes in hemostasis indicators at the onset of COVID-19 were procoagulant and persisted in the post-COVID period. The identified laboratory changes and health abnormalities provide a basis for identifying risk groups among those who have recovered from the disease.

Conclusion . Persistent abnormalities in the immune, coagulation, and health systems of children during the post-COVID period, as well as a low level of protection against infectious diseases and vaccine-preventable infections, are predisposing factors for the development of adverse consequences and allow for the formation of risk groups among children based on their development.

Introduction . The early neonatal period in premature infants is complicated by oxidative stress caused by immaturity of antioxidant defenses.

Objective . To conduct a comparative analysis of metabolic adaptation indicators in premature infants less than 32 weeks of gestation, taking into account the methods of respiratory support used.

Materials and methods . The study included 25 newborns with a gestational age of less than 32 weeks. Patients were divided into two groups: 1) CPAP therapy ( n = 11); 2) mechanical ventilation ( n = 14). The content of superoxide dismutases (SOD1, SOD2, SOD3), glutathione peroxidase (GPO1), malondialdehyde, total antioxidant activity (AOA), and basic metabolic parameters were determined using ELISA and spectrophotometry methods.

Results . In the newborns of the 2nd group, a pronounced intensity of catabolism was revealed at birth. The Ritis coefficient in this group was 20.7 (9.0–21.3), in the 1st 8.5 (6.9–11.3) ( p = 0.046). Serum AOA was significantly lower: 1.4 (1.3–1.5), versus 1.7 (1.5–1.9) mmol/l in group 1 ( p = 0.046). By the 4th day of life, normalization of the blood anabolic reserve and a decrease in the intensity of catabolism were observed in both groups. However, in patients on mechanical ventilation, the antioxidant protection indices were significantly lower than in the CPAP group: SOD1240.5 (230.6–251.1) versus 256.4 (246.9–262.4) ng/ml ( p = 0.006); SOD2–1.9 (1.5–5.5) versus 4.7 (4.6–7.2) ng/ml ( p = 0.005); and GPO1–22.6 (17.1–26.7) versus 26.6 (23.0–29.9) mg/ml ( p = 0.010); in addition, children in group 2 showed a statistically significant decrease in SOD2 over the course of observation ( p = 0.032).

Conclusions . Children requiring mechanical ventilation to manage respiratory distress experience more pronounced depletion of antioxidant capacity and activation of peroxidation. Children who require only CPAP therapy experience a more gentle approach, with metabolic adaptation occurring more physiologically and preserving protective mechanisms by 4 days of life.

Pathological aging of the kidneys is characterized by cellular senescence, inflammation, and fibrosis. The main regulator in this process is TGF-β1, which is secreted as part of the senescence-associated secretory phenotype (SASP). We have modeled accelerated aging using H2S and CsA, which induce oxidative stress.

The aim of the study was to evaluate the effect of H₂S and CsA, both individually and in combination, on the expression of TGFβ1 and the development of senescent changes in the kidneys of aged laboratory rats.

Materials and methods S . The study was conducted on 44 male white rats older than 18 months in 4 groups: control, H2 (0.26 mmol/day, 10 days), CsA (20 mg/kg/day, 25 days), and H2S+CsA. The kidney paraffin sections were analyzed morphologically and immunohistochemically (QuPath TGFβ1positive cell percentage). Statistical analysis: Kruskal–Wallis test. Results . The highest percentage of TGF-β1positive cells was found in the combined exposure group: up to 7.86 [7,64; 8,03] % in the tubules and up to 7.77 [7,61; 7,95] % in the interstitium. In the isolated exposure to H2S and CsA, the percentage of TGF-β1-positive cells was less: 4.97 [4,68; 5,66] % и 5.71 [5,47; 5,81] % in the tubules, respectively. Conclusion . The combined effect of H₂S and CsA synergistically increases the proportion of TGF-β1-positive cells in the tubules and interstitium of the kidneys, promoting senescence and fibrotic remodeling. TGF-β1 acts as a key marker and driver of pathological kidney aging.

Introduction . The significance of gestational diabetes mellitus (GDM). The presence of a uterine scar worsens the perinatal prognosis.

Objective . To study the characteristics of the maternal history, pregnancy course, delivery, postpartum period, and morphological determinants of uterine scar defects in patients with gestational diabetes mellitus.

Materials and Methods . A retrospective cohort comparative study of the course and outcomes of pregnancy was conducted in 101 patients with a uterine scar following cesarean section (CS). Of these, 60 (the study group) were diagnosed with gestational diabetes mellitus. The comparison group consisted of 41 patients without GDM. Medical history, ultrasound data, and shear wave echo elastography were reviewed. Scar tissue was sent for histological examination. Results . The parity of pregnancy in patients of the main group is significantly higher; the anamnesis includes significantly more often induced abortions and obesity. The main complication of the current pregnancy is the threat of termination (OR 2.39 at 95 % CI [1.013–5.623]). Elastographic study revealed a significant positive correlation be_r_ tween the stiffness index and the presence of GDM ( = 0.82), the OR of uterine scar insufficiency in patients with gestational diabetes mellitus significantly increases and is 1.92 at 95 % CI [1.276–2.896]. When analyzing the clinical and morphological variants of scar insufficiency according to histological examination data, the “vascular” variant was confirmed significantly more often.

Conclusion . The main causes of uterine scar insufficiency in patients with gestational diabetes, increased tissue stiffness in diabetes, fetal macrosomia, and vascular wall changes are associated.

Introduction . Th e search for compounds capable of modulating key mechanisms of aging remains one of the pressing challenges of modern medicine. Fucoxanthin, a carotenoid derived from brown algae, possesses antioxidant and anti-infl ammatory properties; however, its eff ects on complex biomarkers of aging in mammals remain insuffi ciently studied.

Objective is to comprehensively evaluate the eff ects of long-term oral administration of fucoxanthin on biomarkers of aging, including pro-infl ammatory cytokines, advanced glycation end products, and metabolic parameters in aging mice.

Materials and methods . Th e study included 30 male ICR/CD1 mice divided into three groups: 1) mature controls (10 months), 2) aged controls (18 months), and 3) aged mice receiving fucoxanthin (18 months) at a dose of 20 mg/kg body weight per day for 8 months. Serum levels of IL-6, TNF-α, MCP-1, and AGEs, as well as biochemical parameters, were assessed.

Results . In aged control mice, all measured markers were signifi cantly higher than in mature controls. Fucoxanthin administration contributed to a reduction in IL-6, TNF-α, MCP-1, and AGEs levels, along with an improvement in the metabolic profi le (decreased glucose, triglycerides, ALT and AST activities, and increased HDL cholesterol and albumin).

Conclusion . Th e obtained results demonstrate a comprehensive geroprotective eff ect of fucoxanthin, refl ected in suppression of the senescence-associated secretory phenotype, reduction of carbonyl stress, and improvement of metabolic status. Th ese fi ndings support the potential of fucoxanthin as a promising geroprotector for further research in the prevention of age-associated diseases.

Introduction . Deep infiltrative endometriosis is a serious disease that often affects adjacent organs such as the bladder and intestines, which requires surgical treatment. At the same time, surgical intervention itself carries the risk of developing early postoperative and long-term undesirable consequences. A number of such consequences are known, in particular, detrusor dysfunction, but it is an extremely difficult task to take into account all possible options for the development of the postoperative period. Here is an example of a difficult-to-predict complication that occurred one year after laparoscopic bladder resection.

The purpose of the work is to describe a non-traumatic (spontaneous) bladder rupture associated with deep infiltrating endometriosis using a clinical case as an example.

Materials and methods . Medical documentation, including surgical protocols, observations, and data from a comprehensive laboratory and instrumental examination of the patient, was used.

Results . A detailed analysis of a clinical case of non-traumatic bladder rupture was conducted. The patient’s subjective complaints, objective symptoms, diagnostic methods, and surgical treatment were studied. Recommendations for the treatment approach and subsequent postoperative management of patients with deep infiltrating endometriosis were formulated.

Conclusion . The given clinical example indicates the need for a comprehensive interdisciplinary approach to the treatment of endometriosis when the urinary tract is involved. When urination disorders occur, it is advisable to conduct diagnostic studies to identify the cause of the phenomena and correct them in a timely manner.

In modern obstetrics, the management of HIV-positive pregnancies has undergone a paradigm shift, primarily due to the widespread implementation of antiretroviral therapy. While these interventions have drastically reduced vertical transmission and maternal opportunistic infections, several clinicopathological challenges persist regarding the long-term impact on the maternal-fetal unit. Current scientific inquiry is focused on identifying biomarkers and genetic markers to enhance risk stratification.

The purpose of this review is to summarize current data on the course of pregnancy, childbirth, and the postpartum period in women with HIV-positive status, analyze available domestic and foreign clinical studies, and evaluate the effects of HIV infection on the placenta, including histological and immunohistochemical changes.

Materials and methods . When preparing the review article, publications from international and Russian scientific resources were used: PubMed/MEDLINE, Cochrane Library, as well as national databases eLibrary.ru and materials from specialized journals on obstetrics and gynecology, infectious diseases and epidemiology, and genetics. The analysis mainly included works from 2018–2026, with earlier key publications involved, if necessary. The search was carried out using combinations of keywords, as well as their Russian equivalents: “pregnancy, HIV infection, pregnancy complications, placenta, vertical transmission of HIV, genetics, preeclampsia”. The selected publications were critically evaluated, then divided into thematic areas and summarized.

Interleukin-6 (IL-6) is a prototype cytokine with pleiotropic and excessive functional activity. It regulates inflammatory infiltrate maturation, promotes neutrophil migration and mononuclear cell infiltration, and acts as a chemoreceptor for monocytes in the inflammation focus. These mechanisms are crucial in rheumatoid arthritis (RA) development and therapy. Small non-coding ribonucleic acids (microRNAs) can regulate IL-6 levels in peripheral blood and the inflammation focus by targeting the IL6 gene expression. Understanding the role of microRNAs in RA can help develop innovative diagnostic methods and personalized treatment approaches. This review aims to update knowledge on epigenetic biomarkers of RA and systematize the results of clinical studies evaluating the relationship between circulating microRNA expression and circulating IL-6 levels in RA patients. The authors searched PubMed, ClinicalKey, Scopus, Cochrane Database, Google Scholar, and eLIBRARY.ru for relevant publications using specific keywords and their combinations. Publications from 2014 to 2025, including original clinical studies of RA, were analyzed. This descriptive review demonstrates that circulating microRNAs can be considered promising molecular biomarkers of RA. However, implementing epigenetic study results into routine rheumatological practice remains challenging due to the ambiguous results of previous studies and the necessity to account for both direct and inverse relationships between changes in specific circulating microRNAs and IL-6 levels in the blood of RA patients.

Background . Hypogonadotropic amenorrhea (HA) is a common cause of menstrual absence in adolescent girls and young women. It is based on a violation of the neuroendocrine-metabolic mechanism that regulates the reproductive cycle in the female body, due to the complex combined action of various social, environmental, nutritional and psychological factors. The exact mechanisms underlying the pathophysiology of GA are complex, and their study is ongoing.

The aim of the study . Conducting a scientific analysis of domestic and foreign publications devoted to the problem of hypogonadotropic amenorrhea, using the example of functional hypothalamic amenorrhea to summarize the current understanding of its pathophysiological mechanisms and discuss the clinical significance and potential practical application of these findings.

Materials and methods . A search and analysis of scientific publications in open electronic databases was carried out PubMed, eLibrary for the period from 2015 to 2025.

Results and discussion . Hypogonadotropic amenorrhea is a complex neuroendocrine pathology with a number of serious consequences for the health of the female body, affecting not only the state of the reproductive system, but also the health of the musculoskeletal, cardiovascular and central nervous systems, as well as the metabolism of the adolescent body as a whole.

Conclusion . Deep understanding and analysis of the pathogenetic mechanisms of development and the clinical and biological consequences of hypogonadotropic amenorrhea using the example of functional hypothalamic amenorrhea is crucial for a practicing gynecologist in terms of preventing long-term consequences for somatic and reproductive health.