卷 50, 编号 5 (2024)

The localization of start and turn points in rhythmic sound movement created through the modeling of binaural beats (BB) was investigated. The BB-modeled broadband stimuli consisted of stationary initial and final segments with a section of cyclic motion between them. Spatial effects were induced by changes in the interaural time difference (ITD). During the experiment, subjects assessed the position of the movement trajectory ends or the position of reference points using a graphic tablet. It was discovered that the perception of rhythmic movement of the sound image was significantly influenced by the integrative ability of the binaural auditory system. The results indicated that with instantaneous switching between stationary segments, the perceived positions of the trajectory ends (start point and turn point) matched the positions of the reference points. Conversely, the smooth movement between the same extreme values showed a displacement of the trajectory ends: the turn points were localized further from the reference points compared to the start points, at all trajectory positions in space. Localization of the trajectory end crucially depended on the time that the sound had stayed near the turning point. These patterns were expressed stronger in the central area of the acoustic space compared to the periphery.

A comparative study of the volume-velocity parameters of the human external respiration system was carried out under the influence of an additional weight load: a body armor weighing 11 kg and a backpack weighing 15 kg. The nature of changes in the main spirometric parameters under the influence of an added mass is typical for restrictive disorders of pulmonary function. A marked decrease in forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV₁) values was observed when performing the test with a protective vest. In the conditions of a combination of body armor and a backpack, these changes were more pronounced (p < 0.01). At the same time, there were no significant changes in the Tiffno index values (FEV₁/FVC). In addition, a significant decrease in the values of maximum voluntary ventilation (MVV) was revealed by 8.1% under the influence of body armor, and by 18.5% with a combination of a vest and a backpack relative to the control (p < 0.01). A significant correlation was shown between the maximum force of contraction of the inspiratory muscles and the maximum voluntary ventilation of the lungs both in the control and with an additional weight load. It is possible that the inspiratory muscles training, aimed at increasing their strength and endurance, can be an effective strategy for minimizing the adverse effects of increased weight load when performing work with special protective equipment in various areas of human professional activity.

The relationship between adrenergic reactivity of isolated myocardium of the human right atrial appendage in coronary heart disease (CHD) with preserved and reduced ejection fraction (EF) of the left ventricle (LV) upon stimulation of β₁-adrenergic receptors (β₁-AR) with echocardiography (EchoCG) parameters was studied. It has been shown that adrenergic reactivity, assessed by changes in the force of contractions of isolated myocardial strips in response to stimulation of β₁-AR, in patients with preserved LVEF has positive dynamics at 20-minute observation. In reduced LVEF, adrenergic reactivity in response to β₁-AR stimulation is weakened and does not have positive dynamics. In patients with CHD, myocardial adrenergic reactivity associated with β₁-AR is a significant factor in determining intracardiac hemodynamics. This is manifested in the presence of correlations between the mechanical response of isolated myocardium upon stimulation of β₁-AR and the results of echocardiography, and such correlations have different directions in patients with preserved and reduced EF. The discovered differences in the correlation of cardiac ultrasound parameters with the inotropic response of isolated myocardial fragments upon stimulation of β₁-AR with preserved and reduced EF probably reflect the different severity of cardiac chamber remodeling and the state of general neurohumoral regulation in the conditions of the pathology under consideration.

A study of blood samples of 18 cosmonauts who had long flights as members of Russian crews of the International Space Station was performed using the method of quantitative proteomics based on mass spectrometry. The study was focused on elucidation of possible connection of proteome changes under the influence of space flight (SF) factors with the processes of angiogenesis. The analysis was performed with a targeted panel of 125 labeled 13C/15N peptides using chromatography-mass spectrometry with multiple reaction monitoring (LC/MRM-MS). A total of 125 different proteins were quantitatively characterized. Among them, a group of 61 proteins involved in the processes of angiogenesis and its regulation was found. Bioinformatic methods showed that the isolated angiogenesis proteins were participants of 13 biological processes, including lymphangiogenesis. Significant changes of protein level in blood after landing, in relation to preflight samples, were observed in 7 cases. The results have shown that the elimination of gravity (microgravity), space radiation and overloads of the final stage of flight have a combined effect on the processes of angiogenesis, which is manifested by changes in proteomic composition on 1 day after the completion of long-term CP.

A new personalized approach is proposed to predict the professional suitability of railway transport workers under the influence of stressful factors, based on the study of the effect of salivary fluid of subjects before and after a work shift on the intensity of the glow of the bioenzyme reaction of luminous bacteria: NADH:FMN-oxidoreductase+luciferase. The integral method, which signals the magnitude of the stress effect, is based on changes in saliva components such as lactate, ions and cations, as well as nitrate and sulfate chlorides under the influence of stress. This made it possible to identify, using the example of Russian Railways dispatchers, a risk group and a group of stress-resistant workers, which is important to reduce accidents at Russian Railways. The conditions that reduce the stressful workload necessary for the development of effective measures for the prevention of stressful situations and the preservation of workers’ ability to work have been identified.

In order to determine the prognostic value of the dynamics of the blood sodium/potassium ratio in critical conditions during thermal trauma, the concentration of electrolytes was retrospectively studied in 107 patients with a combustological profile, 64 with a fatal outcome, 43 with a favorable outcome. It was found that an increase in the blood sodium/potassium ratio above 39 in dynamics indicates the possibility of a fatal outcome of a patient with thermal injury in the next 7–10 days.

Currently, a new approach to the concept of “inflammation” has been formed. Increasing evidence indicates that cellular and molecular mediators of inflammation are involved in a wide range of biological processes, including tissue remodeling, metabolism, thermogenesis, and nervous system function. Given the diversity of biological processes involving inflammatory signals and cells, the traditional view of inflammation as a response to infection or tissue damage is incomplete, since inflammation can occur in the absence of these triggers. The review examines the effects caused by myokines produced during physical activity. It can be argued that these proteins are involved in ensuring adaptive changes, pro- and anti-inflammatory reactions to maintain homeostasis, and their overall effect can be characterized as physiological inflammation. At the same time, the mechanisms of transcription activation of many myokines differ significantly from similar mechanisms in cells of the immune system. This suggests that myokines can be considered as factors of physiological inflammation, which is not a pathological process, but ensures normal physiological reactions during physical activity. A hypothesis has been formulated about the role of myokines as factors stimulating the development of physiological inflammation. The effects caused by myokines produced during physical activity are involved in ensuring adaptive changes, anti-inflammatory reactions and maintaining homeostasis. Physiological inflammation can be considered as, in some way, an antagonist of pathological inflammation; it is due to this antagonism that many positive effects of physical activity, including metabolic disorders, can be realized.