№1, 2025, volume 21

The article presents the scientific and practical contribution of Professor L. I. Los to the development of hygienic science and sanitary affairs for the 50-year period of his work at the Kazan and Saratov Medical Institutes (1923-1974), as well as highlights the main scientific research conducted by the staff of the Department of General Hygiene, the Saratov Research Institute of Rural Hygiene and the Communal Department of the Saratov Regional Sanitary and Epidemiological Station under his leadership, the results of which were implemented in practical health care. The work reflects the issues of organizing the educational process at the Department of General Hygiene for students and the training of scientific and pedagogical personnel for medical universities of the country. His active social activity in scientific and medical societies and participation in АН-Union and All-Russian congresses, and conferences of hygienists are shown.

The article presents the main facts of the professional biography of Oleg Alexandrovich Tsarev, Doctor of Medical Sciences, Professor of the Department of Hospital Surgery, Faculty of Medicine, V. I. Razumovsky Saratov State Medical University, reflecting his achievements as a surgeon and scientist.

Objective: to analyze the antibacterial effect of bioformed silver nanoparticles on the museum and clinical strain of Pseudomonas aeruginosa in vitro. Material and methods. Silver nanoparticles were obtained using metabolites of the non-pathogenic bacterium Azospirillum brasilense SR80. The size, shape, homogeneity and degree of aggregation of the obtained nanoparticles were characterized by electron microscopy, UV-visible spectroscopy and dynamic light scattering. The antibacterial effect of various concentrations of silver nanoparticles was assessed by the level of metabolic activity of cells using the resazurin test. Results. Biosynthesized silver nanoparticles exhibited antibacterial activity against the reference strain P. aeruginosa ATCC 27853 and the clinical strain P. aeruginosa. A decrease in the metabolic activity of bacterial cells was shown, depending on the concentration of nanoparticles. Maximum antibacterial activity (100% cell death) for the reference strain P. aeruginosa was achieved when the cells were treated with silver nanoparticles at a concentration of 12,5 ug/ml, for the clinical strain, complete suppression of cell growth was noted when adding nanoparticles at a final concentration of 25 ug/ml. Conclusion. Silver nanoparticles obtained by the "green" synthesis method using the cell-free extract of Л. brasilense SR80 exhibit pronounced concentration-dependent antimicrobial activity against the clinical and standard strains of P. aeruginosa in vitro.

Objective: to analyze anatomical and hemodynamic transformations in the umbilical cord vascular bed during labor using computer modeling of physiological processes and the associated change in the external pressure gradient. Material and methods. The first stage of this work included three-dimensional modeling in Ansys Fluent 2021 of a single straight umbilical artery under external pressure of 120 mmHg. The second stage consisted of 3D modeling of the umbilical vessel organ complex surrounded by fetal mucous connective tissue under similar external pressure. Results. In an isolated straight umbilical artery, when exposed to external pressure, the blood flow velocity increases by 85.5%, intravascular pressure by 38.5%. In three-dimensional modeling of the entire umbilical cord under similar pressure, the blood flow velocity in the umbilical arteries increased by 20%, intravascular pressure increased by 8%. In this case, the blood flow velocity in the umbilical vein increased by 24%, intravascular pressure by 10%. The cross-sectional area of fetal mucous connective tissue, umbilical arteries and vein did not change, despite the external deformation of the umbilical cord, vascular wall and change in the lumen of the vessels. Conclusion. Anatomical and hemodynamic parameters in the umbilical vessels in the intranatal period undergo transformations of varying degrees of severity. These changes consist of an increase in intravascular blood flow velocity and pressure, deformation of the umbilical cord and vascular wall, narrowing of the lumen of the vessels, while maintaining the cross-sectional area of the umbilical cord and its vessels against the background of external pressure.

Objective: to assess the level of absenteism, presenteeism, general decline in productivity and daily activity in persons suffering from substance use disoders. Material and methods. The object of the study is patients undergoing treatment for addiction to a psychoactive substance in the inpatient department of a narcological dispensary. At the first stage, patients were determined to have an employment relationship within the last year. Then, at the second stage, the working patients answered the questions of the Work Productivity and Activity Impairment Questionnaire, which assesses the impact of the disease on indicators of labor activity. Results. The level of absenteism in patients was 7.1 hour per week, or 13.8%. The average value of presenteeism in the group of those who actually worked during the study period was 60.2% working hours, which in absolute value corresponds to an average of 31.0 hour per week per patient. The overall decrease in productivity (OSP) was 63.5%. Daily activity (PA) was reduced by 56.7% in all patients included in the study. Conclusion. Substance dependence syndrome has a significant impact on the ability to perform the work functions of patients, reducing them. A significant decrease in daily activity was also revealed.

Objective: to verify the characteristics of the social portrait of pregnant women with complicated pregnancies associated with prenatal risk. Material and methods. The study included 385 pregnant women. The average age is 29.0±0.5 years. Questionnaire and differentiation of respondents according to the degree of prenatal risk were carried out using the scale of prenatal risk factors V. E. Radzinsky et al., According to which respondents are divided into low, medium and high prenatal risk groups. Spearman's correlation coefficient was used for correlation analysis of the characteristics of the social portrait of respondents and the degree of prenatal risk of complicated pregnancy. Results. The characteristics of the social portrait of pregnant women associated with prenatal risk include: age and education of respondents, age and education of the husband of respondents, family composition, number of children, number of minor children, number of previous pregnancies, smoking and alcohol consumption. The most correlated with the degree of prenatal risk: the number of previous pregnancies +0.45 (p<0.001), the age of the husband +0.39 (p<0.001), the age of the woman +0.34 (p<0.001). Conclusion. The study verified the characteristics of the social portrait of pregnant women associated with the prenatal risk of complicated pregnancy. The relationship between the social characteristics of respondents and the degree of prenatal risk of complicated pregnancy was established.

Objective: to assess the influence of the characteristics of marital and parent-child relationships on the formation of self-attitude in adolescents with chronic gastroduodenitis. 37 adolescents were examined, average age 15,5±1,2 years. The studies were conducted in a mother-child pair, a total of 37 pairs. Material and methods. «Questionnaire of Parental Attitudes to the Child» by AYa Varga, VV Stolin, «Family Life through the Eyes of the Mother» by ES Sheffer and RK Bella adapted by TV Neshcheret, «Parent-Child Relationships of Adolescents» by PV Troyanovskaya, the «SHSO» method — the family environment scale by EG Eidemiller, «Methodology for the Study of Self-Attitude» by SR Pantileev, the projective method «Unfinished Sentences» by D Saks — S Levy. The conversation method was used in the analysis of individual cases. Statistical method: linear regression analysis was performed to identify the contribution of predictors to the overall variance of the self-attitude indicator. Results. The contribution of predictors to the change in the self-attitude index of adolescents with chronic gastroduodenitis was determined, the significance level of their contribution to the variance of the dependent variable was p<0.05: authoritarian hypersocial-ization (R2=35%, (3=-0,037), hostility towards a spouse (R2=25%, (3=-0,313; R2=54%, (3=-0,397; R2=33%, (3=-0,278; R2=28%, (3—0,287; R2=31%, (3=0,369), intellectual-cultural orientation (R2=17%, (3=0,738); irritability, maternal temper (R2=13%, (3—0,141), autonomy promotion (R2=30%, (3=0,312), acceptance (R2=25%, (3=0,201), activity orientation (R2=20%, (3=0,868), emotional distance (R2=25%, (3=0,221), decision making (R2=37%, (3—0,259), demanding (R2=23%, (3=0,394), independent (R2=24%, (3—0,894). Conclusion. The presence of marital conflicts, the lack of mom's interest in the child impede the teenager's positive attitude towards herself and contribute to the formation of intrapersonal problems.

Objective: determine structural patterns of disease burden of atopic dermatitis (AD) and comorbid conditions in adult patients. Methodology for writing a review. A literature search was conducted using Medline, PubMed, and eLibrary databases. Search terms included: "atopic dermatitis", "burden of disease", "comorbid conditions". The number of sources considered is 53. For the final analysis on the issue under consideration, 32 sources from 2006 to 2023 were included, reflecting the influence of structural patterns on the quality of life of adult patients with AD. Conclusion. The disease burden of AD in an adult cohort of patients is reflected in the structural components of quality of life. Self-perception, psychosocial, academic and professional spheres are most affected by AD and are structural patterns of the true disease burden. Reduced physical activity and missed educational opportunities in childhood, affecting adulthood, reflect the hidden disease burden. Clinical features of the dermatosis: hereditary, chronic, recurrent nature of the disease, dysfunction of the skin barrier, increased risk of comorbid conditions reflect the individual disease burden. The degree of impact of AD on the quality of life of not only patients but also their family members demonstrates the cumulative burden of the disease. The economic component of the cost of the disease, as well as indirect costs associated with a decrease in the working capacity and productivity of patients, reflect the high index of the negative impact of AD.

Objective: identification of the relationship between the receipt of preferential drug provision and the development of recurrent vascular events and hospitalizations according to the data of the survey of patients who had suffered myocardial infarction. Material and methods. The study included 304 respondents (68% men, age 62 [47; 72] years, 63.4% — rural residents). At the time of the survey, 74.3% of the respondents were eligible for preferential drug provision. A sociological study using an original questionnaire was implemented through individual oral interviews. Re-sults. The overwhelming majority of respondents were aware of the possibility of undergoing rehabilitation measures (70%) and receiving preferential medications (90%) after suffering a myocardial infarction. Regularly, 188 (61.8%) patients take medications. Of these, 147 (78.2%) receive preferential drug provision. Dispensing of discounted medications to patients after vascular events showed a trend toward decreased seeking of medical care by this cohort of patients, with an odds ratio of 0.026 (95% confidence interval 0.012-0.056). Conclusion. In the Saratov region, there is a significant reduction in emergency medical calls and hospitalizations among patients receiving preferential drug provision within the framework of the Federal Project "Fight against Cardiovascular Diseases."

Objective: to study the effectiveness of multidrug- and pre-extensively drug-resistant tuberculosis (ТВ) chemotherapy regimens with the inclusion of linezolid (Lzd) and bedaquiline (Bq) in operated patients for pulmonary ТВ. Material and methods. A non-randomized continuous single-center retrospective study of the data of 154 patients operated of NMRC PhPL for drug-resistant pulmonary tuberculosis in the period from 2018 to 2023 was performed. A comparative analysis of the effectiveness of chemotherapy regimens was carried out depending on the inclusion of new anti-tuberculosis drugs in it. Results. The proportion of adverse reactions in both observation groups when prescribing anti-tuberculosis drugs, excluding the use of Lzd and Bq, was comparable. Undesirable side effects were observed in 24.1% (n=21/87) in group 1 and in 25.4% (n=17/67) in group 2. The inclusion of Lzd and Bq in the postoperative chemotherapy regimen allowed a statistically significant reduction in the duration of the course to 38.5±2.1 weeks compared with the control group, where this period was 44.6±2.2 weeks. Thus, the timing of a favorable outcome was reduced by 6.1 weeks (p<0.05). Adverse reactions occurred in 24.1 % of patients treated with Lzd and Bq. Conclusion. The inclusion of Lzd and Bq in the multidrug- and pre-extensively drug-resistant ТВ chemotherapy regimen makes it possible to reduce the total duration of the course until a favorable outcome occurs.