Vol 27, No 4 (2020)

National programs for monitoring chloro-organk compounds (С0С) in the human body have been introduced in different countries. In Russia, this monitoring began at the end of the 20th century. In the Russian Far East, only preliminary data on the accumulation of chloro-organk compounds in the human body have been published so far warranting further research. Thus, the aim of this study was to assess the accumulation of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in breast milk of women in the South of the Russian Far East and the compare the findings with the data from 2017. Methods. Breast milk was collected in health institutions in the region (Primorsky Krai). The age of the women ranged from 20 to 49 years. The concentrations of OCPs and PCBs in breast milk samples werestudied by gas chromatography mass-spectrometry. Results. The content of ГОС (EHCHs + EDDTs + EPCBs) in the samples ranged from 23 to 878 ng / g lipids. The concentration ranges of OCPs (EHCHs + EDDTs) and PCBs were 2.8-291 and 3.2-720 ng / g lipids, respectively. Conclusions. The total OCP content in the samples taken in 2018 year was greater than the corresponding data from 2017 (p = 0.035) in all age groups of women. HCH concentrations in 2018 significantly exceed those in 2017 (p = 0.016 and p = 0.008 - according to different evaluation criteria). DDT and its metabolites were below the detection limit in 50 % of samples. The total concentration of PCBs in 2018 was lower than in 2017.

The aim of the study was to assess physical performance over a five-years period in young male cross-country skiers living in the Russian North. Methods. Anthropometric data and parameters of blood circulation, respiration and energy expenditure were studied in 20 skiers aged 15-20 years in the Komi Republic. A bicycle ergometer with Oxycon Pro system (Germany) was the main assessment instrument. Tests were performed twice - at the beginning and in the end of a five-years period. Results. A statistically significant increase in body weight and body mass index, a decrease in heart rate (HR), systolic blood pressure, pulse pressure, double product (DP) and the vegetative Kerdo index at rest were observed indicating an increase in physical fitness. At a load of 200 W, a decrease in heart rate, DP, oxygen consumption and energy expenditure and an increase in efficiency were found suggesting economization of blood circulation and energy reactions during standard operation. However, at maximum load an increase in blood pressure from (185.0 ± 15.2) to (195.0 ± 11.6) mm Hg p = 0.038; a decrease in the maximum oxygen consumption from (67.4 ± 6.20) to (61.4 ± 7.21) ml / min x kg, p = 0.012; decreased oxygen consumption on the brink of anaerobic metabolism from (4,036 ± 594) to (3,623 ± 593) ml / min, P = 0.040; and heart rate on the brink of anaerobic metabolism from (171.0 ± 11.6) to (157.0 ± 16.5) bpm, p = 0.005 was revealed suggesting a decrease in the maximum functional capabilities of the body. Physiological costs of a unit of work for various indicators of blood circulation, respiration, and energy expenditure have not changed over a five-years period (p values varied from 0.082 to 0.935). Conclusions. The observed decrease in the level of physical performance by aerobic and anaerobic thresholds may suggest not only the beginning of age-related changes in the body of athletes in the North, but may also reflect possible negative impact of living conditions in the North.

The article summarizes the evidence on the biological role of copper and the role of copper metabolism disorders in neurodegenerative processes and pathogenesis of autism. The neuromodulating effects of copper ions and their role for cognitive functions are described. The results of original studies on copper metabolism in children with autistic disorders (AD) arepresented. Our review suggests that the current evidence is contradictory. While several publications indicate an increased level of copper in blood, hair, teeth, nails of AD patients, other studies do not report any difference in the concentration of copper between AD and healthy children. It isassumed that the dysregulation of copper metabolism in children with AD is associated with dysfunction of transport proteins. Data on copper involvement in the processes of management of free radical in children with AD arediscussed. Monitoring of metal-ligand homeostasis in children with AD iswarranted as well as the development of effective methods of correction of copper metabolism disorders.

The aim of this paper is to study the age-related features of the components of the postural balance (CPB) in elderly women with preserved postural stability. Methods. In total, 424 women aged 60-69 years who did not experience a single fall in the last 12 months were examined. Women were divided into two groups: 60-64 years old (n = 251) and 65-69 years old (n = 173). To assess the CPB, a Sensory Organization Test (SOT) of the Computerized Dynamic Posturography «Smart Equitest Balance Manager» was performed. Results. When analyzing the quality indicators of the equilibrium function in functional tests 1-4 and 6, as well as the postural maintaining strategy (PMS) in 1-6 SOT conditions, no statistically significant differences were found between the groups (p > 0.1), but quality indicators of the equilibrium function in test 5 in women 65-69 years old were greater (p = 0.045) than in their younger counterparts. Quality indicators of the equilibrium function and SOT PMS did not differ between the groups indicating that women 65-69 years old who did not experience falls did not show changes in adaptive capabilities, as well as static and statodynamic neurophysiological mechanisms to maintain the balance. Analysis of somatosensory and visual (visual-spatial) information in balance control also did not reveal age-related changes between the groups. However, vestibular information indicators in monitoring balance maintenance in women 65-69 years old were higher (p = 0.045). Conclusions. The indicators of the equilibrium function in test 5 and the effectiveness of vestibular information in controlling the balance of women after 64 years will determine the preservation of postural stability functions and may have a beneficial effect on their life expectancy, and also determine the risk of premature changes in CPB.