Transition to machine learning, personalized medicine, and high-tech healthcare requires up-to-date medical personnel. The higher medical school is transforming the system of training specialists using modern digital technologies and is starting education in the associated pre-universities, thus necessitating research into effects of current technologies on the functional state of high school students. Materials and methods: In April 2019, based on voluntary informed consent, we examined 181 healthy Moscow medical pre-university students (15-17 years of age) and assessed the impact of learning on the central nervous system, musculoskeletal system, and visual analyzer. Results: Traditional lessons in the pre-university are combined with project activities and development of practical skills. Phantom and simulation technologies along with modular construction of the curriculum are used to form practical knowledge and skills. The study load of 38-40 hours a week exceeds hygienic standards. Individual project activities in small groups (up to five students) with teachers last 20 hours a week. Simulation classes are held once a week after the main classes and last 90 minutes with a 5-minute break. Classes using simulation technologies are not always hygienically rational. Study loads, specifics of the timetable and teaching techniques approximated to university ones are adequate to functional capabilities of the body of medical pre-university students. Simulation classes cause no pronounced deviations in the neuromuscular apparatus of students. Most students demonstrate high stress tolerance and a greater motivational readiness for simulation exercises. Emotional tension and high anxiety rates are almost similar during traditional lessons and simulation activities on phantoms. Conclusions: It is advisable to make wider use of modern digital (simulation, phantom, virtual) and design and research teaching technologies including in medical classes of educational institutions.

Introduction: Nowadays, studying the features of influence of mobile devices on stereotypes of children's behavior and communication between children and adults acquires special significance. In modern conditions, a child loses the need for verbal communication and physical activity devoting almost all leisure time to virtual space. As a result, along with the development of specific features of cognitive functions in children their physical activity reduces significantly posing health risks and contributing to excess body weight, obesity, diseases of cardiovascular and nervous systems. Our objective was to evaluate the effectiveness of restrictions imposed on the use of cellphones at schools. Materials and methods: The study was conducted in Novosibirsk in January - March 2020. It involved 454 school children including 228 children who did not use cellphones during school breaks (observation group) and 226 children who actively used cellphones during breaks and lessons (control group). Results: The observation group was characterized by significantly higher energy expenditures related to physical activities with a dynamic component during breaks (p ≤ 0.05) as confirmed by objective data collected by a Polar V800 pulsometer with Polar H10 heart rate sensors, a higher percentage of verbal communications (81.2% against 21.2%), a lower prevalence of posture disorders as detected by computer topography (32.8% against 65.8%) and signs of overexertion of the visual apparatus during the school day among the children having functional visual loss (34.6% against 69.2%). Conclusions: The results prove the effectiveness of restrictions imposed on the children's use of cellphones at school.

Background: Organization of school meals remains one of the important elements of preserving health of schoolchildren. The influence of the alimentary factor is most pronounced in the “sensitive periods” of childhood, one of which is primary school age. Our objective was to do hygienic assessment of nutrition of primary school children in the city of Smolensk and compliance of school diets with the principles of rational and adequate nutrition. Materials and methods: The object of the study included ten educational institutions representing all districts of Smolensk and contractors providing services for organization of school meals. The hygienic assessment of organization of school meals and actual nutrition of primary school children (grades 1-4, 7-11 years of age) was based on valid sanitary regulations. School breakfast and lunch were evaluated from a hygienic point of view. Results: We established that the school diets of younger schoolchildren in urban educational institutions were deficient in nutritional composition and caloric content, irrational and insufficiently balanced. School meals were characterized by a 1.5-1.6 times lower caloric content compared to the dietary reference intake due to a reduced content of proteins, fats, and carbohydrates. The contents of microelements and vitamins were on the average by 10-67% and 15-69% lower than the recommended norms of physiological requirements of schoolchildren of this age group. The lack of fresh fruit and milk in school meals was another unfavorable factor in nutrition of schoolchildren. Conclusion: Our results dictate the need to optimize the diets of schoolchildren and to strengthen production control and sanitary and epidemiologic surveillance of compliance with hygienic requirements for catering in urban educational institutions.

Background: The relevance of scientific research on the impact of digital devices on the well-being of schoolchildren is proved by high prevalence rates of school-related diseases in secondary school students. Our objective was to study various aspects of schoolchildren's vital activities associated with the use of digital devices and to assess their influence on the well-being of teenagers. Materials and methods: In 2019, we conducted an anonymous questionnaire-based survey of 121 sixth to ninth graders (13-15 years of age) of a Moscow school. Results: In 70.0% of the teenagers, a long-term use of digital devices was accompanied by various subjective health complaints including visual disturbances, musculoskeletal disorders attributed to excessive static loads, and nervous system disorders caused by information overload. We observed significant changes in life activities of the respondents: up to 39.0% reported going to bed after midnight and almost 70.0% reported sleeping less than 8 hours; we also noted a general decrease in the amount of time spent outdoors. Less than 32% of the school teens observed the rules of a safe use of digital devices. Conclusions: Two and more hours of using a tablet or a laptop on school days were typical of 39.0%-47.0% of the teenagers while on weekends the rate of those using the laptop more than 4 hours daily increased by 3.6 times. More than half of adolescents (up to 55.7%) reported four or more hours of a smartphone use daily. Sleep disturbances were more frequent among smartphone than in personal computer users (31.7% against 17.0%, p<0.05). Our findings indicate the necessity to pay serious attention to organization of rational leisure activities of adolescents and availability of various attractive forms of physical activity in order to reduce risks of health disorders. Development of sustainable safety skills and culture of the digital device use at school and at home remains relevant among schoolchildren.

Background: The lifestyle of primary school children has a direct impact on the level of physical activity that plays a crucial role in their health improvement. Our objective was to assess gender-specific characteristics of a physically active lifestyle of primary school children. Materials and methods: A questionnaire-based survey of 124 boys and 141 girls aged 8-10 years was conducted to collect information about the main lifestyle factors contributing to the increase in physical activity. Results: Only 12.1±2.7 % of girls and 24.2±3.8 % of boys reported sufficient duration of outdoor activities (р < 0.05). 71.8±4.0 % of boys and 74.5±3.7 % of girls attend sports clubs and take dance classes. The proportion of those doing martial arts and playing sports games was higher in boys than in girls: 35.5+4.3 % against 3.5±1.6 % (р < 0.001) and 20.2±3.6 % against 10.6±2.6 % (р < 0.05), respectively. On the opposite, more girls did complex coordinated sports and took dance classes compared to boys: 41.8±4.2 % against 8.1±2.4 % (р < 0.001). We established that 79.8±3.6 % of boys and 75.9±3.6 % of girls (р>0.05) engaged in physical activity independently and/or with parents. We also found that 16.9±3.4% of boys and 29.8±3.9% of girls did not take part in active рку during school breaks and at leisure (р<0.05). Physical education lessons were enjoyed by 84.7±3.2% of boys and 87.2±2.8% of girls (р>0.05). Conclusions: The lifestyle of modern primary school boys and girls has specific features that must be taken into account when implementing a sex-differentiated approach during physical education classes. It is expedient to engage boys in sports games and exercises that help develop coordination and flexibility and girls - in outdoor and sports games.

Introduction: Inadequate physical activity, eating disorders, irrational factors of the educational environment and a poor motivation for a healthy lifestyle are often observed among youngsters and act as their health risk factors. At the present stage, they hamper ensuring optimal living conditions and achieving better health of schoolchildren and require a new approach to solving the tasks. The objective of the study was to assess provision of sanitary and epidemiologic wellbeing at schools and health of schoolchildren to substantiate priorities for management decision making. Materials and methods: The study was conducted in two comprehensive schools of the city of Penza in 2017-2019 involving 2,672 children and 720 parents. We used sanitary, hygienic, physiological, sociological, and statistical methods of research. Results: The level of sanitary and epidemiologic wellbeing in the experimental school with an up-to-date model of hygienic education and development of a healthy lifestyle integrated in the educational process where students have the opportunity to receive health-improving and rehabilitation medical care, was significantly higher than in the control one. Introduction of the new model of upbringing and functioning of the department for disease prevention and rehabilitation contributed to an increase in students' motivation for a healthy lifestyle and skill consolidation in the behavior of youngsters as confirmed by a larger proportion of such students in the experimental school compared with the control one (75-89% against 50-74%, respectively; p < 0.001). Conclusion: Implementation of management decisions including the upgrade of the system of hygiene education, creation of a healthy lifestyle of students, and organization of the department for disease prevention and rehabilitation on the basis of the educational establishment had a positive effect on students' health.

Background: Scientific substantiation of a health-preserving potential of innovative educational technologies, learning modes, and non-traditional types of student furniture is one of the most important tasks of school medicine. The mode of dynamic postures presupposing alternation of sitting and standing positions at each lesson during the school day has got potential health-preserving resources. Our objective was to assess foot conditions in primary school children in years 1-3 studying in the mode of dynamic postures. Materials and methods: The study was conducted in 2015-2018 involving 42 children aged 7-10 years attending a gymnasium in the town of Balashikha, Moscow Region. The condition of the longitudinal foot arch was assessed by plantography using the Bauerfeind plantograph, Germany. For the same children, the Sztriter index was calculated in the beginning of year 1 and in the end of year 3. Results: The normal longitudinal foot arch was observed in 36.9% and 42.9% of schoolchildren studying in dynamic postures in years 1 and 3, respectively. Flat feet were detected in every fifth child and its prevalence did not change in the course of learning. The most pronounced positive dynamics expressed by a 5.9-fold decrease in the prevalence rate was observed for the higher arch of the foot noted in 21.4% of first graders and only in 3.6% of third graders. Conclusions: Our findings show positive dynamics in foot conditions related to the process of learning in the mode of dynamic postures and may serve as the basis for a wider introduction of this mode into educational practice.

Background: The Sverdlovsk Region is a large industrial area with a high demand for healthy workers. However, learning conditions in vocational schools, apart from study and work load, often have unsatisfactory sanitary and epidemiologic characteristics. Assessment of these factors is an important interdisciplinary task since they can affect health and professional fitness of graduates. Our objective was to analyze health indices in adolescents studying in secondary vocational schools of the Sverdlovsk Region. Materials and methods: We did a statistical analysis of health indices in 15 to 17-year-old adolescents based on data on seeking medical care, results of medical examinations, and disability rates in 2015-2019. Results: We observed a continuous increase in the regional rates of general morbidity and overall incidence (7.8% and 11.1%, respectively), pathological prevalence (16.8%), and disability (13.5%) among adolescents. One third of the regional teenagers studying in secondary vocational schools face additional medical, social, educational, and occupational risks. At present, it is impossible to assess health indicators by school types without conducting special studies. Conclusions: To preserve labor resources, it is necessary to introduce regular school-specific adolescent health monitoring and analysis. Investments in health protection of vocational school students will ensure high economic and social efficiency.

Introduction: A widespread intensive use of electronic devices by modern young people negatively affects their health emphasizing the importance of raising awareness of users about health risks of the uncontrolled use of gadgets and developing appropriate safety skills. High school students can get necessary information in medical institutions, at school, and at home. The objective was to study the role of parents, teachers, and healthcare professionals in forming knowledge, skills and abilities of the safe use of digital devices and related components of a healthy lifestyle in seniors. Materials and methods: In the light of the objective, a special online questionnaire-based survey was conducted in 2019 using Google Forms. It involved 200 schoolchildren in grades 9-11 (15-17 years of age), 251 parents, 389 school teachers, and 220 healthcare professionals. Results: The survey data demonstrated the lowest subjective assessment of risks of the uncontrolled use of digital devices among schoolchildren (p ≤ 0.05) and, at the same time, the highest prevalence of the considered risk factors among them. About 30% of the schoolchildren, 20% of parents and 20% of teachers underestimate behavioral risk factors of the uncontrolled use of gadgets (p ≤ 0.05). I established the leading role of parents in forming the skill of long-term screen time in young people and noted low competence of healthcare professionals in issues of the safe use of digital devices and related components of a healthy lifestyle (using devices in poor lighting, inappropriate places and positions, lacking regular breaks, underestimating risks of low physical activity and eating less than 3 meals a day). I also found that teachers, being aware of safety requirements, comply with them but do not use this experience in their professional activities. Only 65% of schoolchildren and parents and 60% of teachers (p ≤ 0.05) have skills of a safe screen use and take measures to preserve and maintain visual acuity. Conclusions: The survey revealed the importance of improving awareness of the population in issues of the safe use of digital devices, increasing the number of school subjects providing knowledge on this issue and contributing to the development of related healthy lifestyle components, and using all possible sources of transmission of relevant information.

Background: Surface reservoirs remain one of the priority sources of drinking water in the Russian Federation whereas the increasing anthropogenic effect on the environment does not exclude the possibility of contamination of surface waters with toxic compounds. The use of traditional methods of water disinfection with active chlorine aggravates the situation and leads to formation of highly toxic organochlorine compounds. In this regard, one of the urgent hygienic problems is to establish health effect of these toxicants in the population including its most sensitive groups. The objective of the study was to establish and quantify the relationship between concentrations of chloroform and its derivatives in drinking water and blood levels of organochlorine compounds in children consuming potable water with a higher content of chlorine and its derivatives. Materials and methods: The study was conducted on six territories of the Perm Region constituting an observation area where drinking water was noncompliant with hygienic standards by a number of indices, and a comparison area. The analysis of trihalomethanes in drinking water samples was carried out in accordance with the requirements of sanitary regulations SanPiN 2.1.4.1074-01. The levels of trihalomethanes (chloroform, carbon tetrachloride, dibromochloromethane, dichlorobromethane, and 1,2-dichloroethane) in children's blood samples were analyzed by capillary gas chromatography in combination with a specific detector to increase selectivity and sensitivity of determination. We used a Kristall-5000 gas chromatograph with an Optima-5 capillary column (25 m x 0.32 mm x 0.5 μL) and a selective electron capture detector (ECD). Results: The data of comprehensive chemical analyses of average levels of trihalomethanes in blood samples of children consuming drinking water with an increased content of determined compounds (up to 3.5 MPC) and the water complying with hygienic standards are presented. We observed significant differences (p<0.005) between two groups in the blood levels of chloroform, carbon tetrachloride, and 1,2-dichloroethane that were 5.6, 6 and 24 times higher in children of the test group compared to the controls. Conclusion: We revealed a statistically significant causal relationship between the increase in chloroform concentrations in drinking water and the increase in blood levels of chloroform in children described by the equation y=0.00188+0.01782x (R2=0.263, p=0.0018).

Introduction: HIV infection, the disease that develops as a result of infection with the human immunodeficiency virus, has moved from the category of fatal diseases to indolent manageable infections. Urologic diseases are a common complication observed already in the early stages of HIV infection, and the prevalence of kidney disease in these patients ranges from 5% to 30%. Our objective was to analyze urological morbidity in HIV-infected patients hospitalized for emergency and planned indications and to identify the main nosological forms of urological pathology in this population. Methods: For the analysis of epidemiological, immunological and virological characteristics of 91 HIV-infected patients admitted to the Urology Department from June 2016 to December 2019 we reviewed inpatient and outpatient medical histories, structured HIV-infected patients by urological nosologies, assessed stages of HIV infection and values of viral load and CD4+ T-lymphocytes, and established the presence of coinfections. Results: The total of 53 men (58.2%) and 38 women (41.8%) were hospitalized, their average age being 38.2 (± 9.0) years. The analysis revealed the prevalence of acute infectious and inflammatory diseases of the urinary system (pyelonephritis, prostatitis, orchiepidymitis, kidney abscess) and urolithiasis (27.5%), which in some cases required the immediate initiation of empirical antibiotic therapy and emergency drainage of the renal cavity system. Our findings are consistent with the results of studies previously conducted on a different population of HIV-infected patients. Conclusions: Since the Urology Department of Vladivostok Clinical Hospital No. 2 is the main hospital that provides both emergency and planned urology care, our data fully reflect urological morbidity of HIV-infected patients in the city district and can be used for optimization of medical care for this cohort of patients.