Ekologiya cheloveka (Human Ecology)

RATIONALE: At main pipeline transport facilities, the entry of harmful chemicals into the air of the working area can negatively affect the body of workers. The absence in the existing regulatory documents of clearly formulated criteria for the selection of specific harmful chemical compounds to control their content, especially if they are a multicomponent mixture, introduces certain difficulties in identifying pollutants in the air of the work area. The presence of criteria will allow the employer to correctly draw up a production program, the frequency of laboratory tests to obtain more objective and reliable information about the potential harmful effects of chemicals on workers and timely take measures to prevent their negative effects. AIM: Justification of the list of harmful substances for analytical monitoring of their content in the air of the working area of main pipeline transport facilities for oil and petroleum products. MATERIAL AND METHODS: Qualitative and quantitative analysis of the air in the working area was carried out at 12 oil pumping stations and 5 oil product pumping stations located in Russia. RESULTS: Using chromatography-mass spectrometry, the composition of the gas-air environment formed as a result of oil evaporation was determined, which made it possible to determine a list of harmful chemicals for further planned analytical monitoring of their content in the air of the working area. CONCLUSION: Sampling should be carried out in places with the highest probability of gas emissions into the air. When transporting oil, it is necessary to establish strict analytical control at workplaces over the content of aliphatic saturated hydrocarbons C₂-C₁₀, dihydrosulfide mixed with hydrocarbons, benzene in the air, when pumping petroleum products - benzene, gasoline or kerosene, i.e. depending on the type of petroleum product transported. 

AIM: This study explored associations between the -786T>C (rs2070744) genetic polymorphism of the NOS3 gene and the main indices of systemic hemodynamics and heart rate variability following an active orthostatic test in men living in the North. MATERIAL AND METHODS: Eighty-three healthy men aged 33.5±1.5 yеаrs on average, who were permanent residents of the Magadan Region, comprised the sample. The participants underwent both resting and active orthostatic testing modes. Cardiovascular system variables were recorded using an automatic tonometer. Hemodynamic indices were then calculated. Short-term heart rate variability in frequency and spectral areas was simultaneously measured using the Varikard hard&soft complex unit. Genotyping was conducted using polymerase chain reaction. The sample was then divided into two groups: Group 1 consisted of homozygotes with the TT genotype (n=34), while Group 2 comprised carriers of the NOS3*C allele variant (genotypes TC+CC) associated with reduced nitric oxide production (n=49). RESULTS: By examining the complex vasomotor, chrono- and inotropic reactions of hemodynamic and heart rate variables during the active orthostatic test, we were able to discern unique patterns in the response of the two groups under study. Men in Group 1 demonstrated an elevated cardiac output response during orthostatic changes, while maintaining consistent vascular resistance values. This was accompanied by a shift towards sympathetic autonomic activity and an increase in the very low-frequency component of heart rate variability. In Group 2, individuals with sympathetic insufficiency and increased vascular resistance during the orthostatic test showed a 35% increase in the low-frequency component of the cardiac rhythm reflecting the importance of this indicator as a stimulator of blood pressure rhythm fluctuations mediated by baroreflex mechanisms. CONCLUSION: Our findings suggest that men lacking the NOS3*С allele variant in their genotype demonstrate more favorable responses to the active orthostatic test. This may reflect higher level of cardiovascular functional reserves. The 786T>C (rs2070744) polymorphism of the NOS3 gene can be considered as a marker of cardiohemodynamic status and autonomic regulations during functional exercise, such as an active orthostatic test.

BACKGROUND: Myopia typically presents itself between the ages of 18 and 29, affecting both women (35%) and men (59.9%). The prevalence of impaired accommodation and refraction in modern individuals can be attributed to the increased strain on visual sensory systems resulting from the widespread digitalization of various aspects of human life. This increased strain poses a potential risk for alterations in cortical processes related to perception and information processing, increasing the risk of cognitive impairment. AIMS: To study the differences in the characteristics of evoked potentials P300 in 21–23 years old individuals with myopia compared to those without ophthalmic pathology. MATERIAL AND METHODS: An ophthalmological examination was conducted on a group of young individuals aged 21–23 years (average age 22.3±0.1 years) residing in the city of Arkhangelsk. The participants were university students, totaling 54 individuals of both genders (34 females and 20 males). During the examination, uncorrected visual acuity, best-corrected visual acuity, and clinical refraction value (in diopters) were assessed for each participant, along with qualitative changes. Additionally, the reserve of relative accommodation (in diopters) was estimated based on the results of the accommodation study. The study sample consisted of 32 participants without ophthalmic pathology and 22 individuals diagnosed with myopia. The parameters of cognitive evoked auditory potential P300 were measured using an electroencephalograph «NeuronSpectrum- 4/VPM» (Neurosoft, Russia) in both groups. The data were analyzed using the SPSS statistical software package. RESULTS: Students with myopia had longer decision-making times compared to individuals with normal vision, as indicated by auditory evoked potentials P300. This effect was observed in the temporal, mid-frontal, and left frontal regions of the brain. Additionally, the anterior-occipital gradient of P300 amplitude was attenuated, with a high amplitude P300 in the left occipital region. CONCLUSION: Assessment of myopia should be complemented with an examination of the functional status of the cerebral cortex. Extended auditory processing time, activation of both hemispheres and involvement of the occipital regions during the processing of auditory information may be a result of functional reorganization of the cerebral cortex in individuals with myopia.