Bioelectrical Processes Research Articles

Вегетативная регуляция кровообращения и биоэлектрические процессы в миокарде человека в моделируемых гипомагнитных условиях

Today, the prospect of long-term interplanetary missions becomes relevant, that is why it is necessary to understand the changes in the cardiovascular system (CVS) that would occur in hypomagnetic environment. The study was aimed to assess the changes in the CVS mechanisms underlying formation of heart rate variability and bioelectric processes in the myocardium under conditions the 350-, 650-, and 1000-fold reduced Earth’s magnetic field. The experiment (2023) involved 6 male volunteers aged 26–37 years, in whom electrocardiography was continuously performed throughout 32 h. The data obtained were assessed by cluster analysis and analysis of variance. It was found than male volunteers, who belonged to the group showing predominance of parasympathetic effects, had enough functional reserve for critical values (exposure to the up to 1000-fold reduced magnetic field). In volunteers showing predominance of sympathetic modulatory effects, the adaptive response maintenance was ensured by the metabolic regulatory circuit. In this group, the response to the reduced magnetic field exposure was quite pronounced at the threshold of its 350-fold reduction. Our pilot experiment reflecting the effect of the reduced Earth’s magnetic field on the CVS is crucial for development of the concept of further experimental exposures related to magnetic field reduction benefiting space physiology and medicine.

CARDIOGRAPHIC CHANGES IN ACUTE HYPOXIA AFTER INTERMITTENT HYPOXIC TRAINING IN HUMANS

One of the important areas of research in physiology and medicine is the impact of intermittent hypoxic training on human resistance to exogenous and endogenous environmental factors. Special attention is also paid to cardiac activity.
 The aim of the paper is to examine the nature and conjugation of human heart bioelectrical processes in acute hypoxia after intermittent hypoxic training.
 Materials and methods. A 20-minute test with acute hypoxia (AH – 12.3 % O2) was conducted on 29 males, aged 20.2±0.31, at different periods after 16-day-hypoxic training. Blood saturation (SpO2%), amplitude and time ECG parameters were determined.
 Results. At rest, at certain periods after hypoxic training, we observed an increase in R-R (Day 1, p=0.020), Q-T (Day 1, p=0.005; Day 16, p=0.043) and a decrease in P-Q (Day 7, p= 0.016) compared to the control. In case of acute hypoxia there was a decrease in P1II (Day 1, p=0.019; Day 7, p<0.001; Day 16, p=0.003), P-Q (Day 1, p=0.025; Day 7, p =0.002), PQc and QTc (p<0.001), but an increase in T1II (Day 1, p<0.001; Day 7, p=0.005; Day 16, p=0.010), R-R (Day 1, p<0.001; Day 7, p=0.029; Day 16, p=0.002) and Q-T (Day 1, p<0.001; Day 7, p<0.001; Day 16, p<0.001) compared to the control. According to the period after hypoxic training, we observed the dominance of the factor load R-R, Q-T and P1II, T1II, as well as an increase in the canonical correlation of P1II, RII and T1II with R-R and Q-T.
 Conclusion. Intermittent hypoxic training leads to an increase in R-R duration, electrical ventricular systole and a decrease in atrioventricular conduction at rest. In case of acute hypoxia in the period after hypoxic training, all ECG parameters (besides maximum ventricular depolarization) change significantly compared 
 to the control. The paper discusses the factorial significance and the degree of conjugation of bathmotropic and dromotropic cardiac processes.

Characteristics of bioelectric processes in the myocardia of premature newborn children

The article presents the features of bioelectrical processes in the myocardium of premature babies with different gestational age in the neonatal period. The analysis of quantitative electrocardiographic indicators revealed the features of the parameters of the terminal part of the ventricular complex associated with the degree of maturity and age of newborns. At the same time, it was found that during the first month of life in very premature babies significant changes in homeostasis and morphofunctional state of various vital organs and systems occur.

«АВТОВОЛНОВАЯ ПОЛУТЕНЬ» – ТЕРАПЕВТИЧЕСКАЯ МИШЕНЬ В НЕВРОЛОГИИ И МЕДИЦИНЕ

Mathematical modeling of neurophysiological and neuropathological processes and conditions is one of the clusters of neuroscience development. This problematic article provides examples of autowave processes (AVPs) described to date in various areas of Neurology and Medicine, and also demonstrates possible directions/prospects for the further use of the AVP theory in clinical practice. The concept of “autowave penumbra” is introduced, which reflects a change in the nature of bioelectrical processes in active mediums of the body (the nature of self-organization of the neuronal pacemaker activity and/or the nature of the propagation of depression/depolarization waves) with the formation of self-sustaining pathological electrophysiological (bioelectric, autowave processes) that manifest themselves and changes in immune responses (activation of cytokines, for example), excessive neurodegeneration (activation of neuronal apoptosis, for example), etc.

Transplantation of fragments from different planaria: A bioelectrical model for head regeneration

Head-tail planaria morphologies are influenced by the electric potential differences across the animal’s primary axis, as evidenced e.g. by voltage-sensitive dyes and functional experiments that create permanent lines of 2-headed but genetically wild-type animals. However, bioelectrical and biochemical models that make predictions on what would happen in the case of spatial chimeras made by tissue transplantation from different planaria (different species and head shapes) are lacking. Here, we use a bioelectrical model to qualitatively describe the effects of tissue transplantation on the shape of the regenerated head. To this end, we assume that the cells may have distinct sets of ion channels and ascribe the system outcome to the axial distributions of average cell potentials over morphologically relevant regions. Our rationale is that the distributions of signaling ions and molecules are spatially coupled with multicellular electric potentials. Thus, long-time downstream transcriptional events should be triggered by short-time bioelectrical processes. We show that relatively small differences between the ion channel characteristics of the cells could eventually give noticeable changes in the electric potential profiles and the expected morphological deviations, which suggests that small but timely bioelectrical actions may have significant morphological effects. Our approach is based on the observed relationships between bioelectrical regionalization and biochemical gradients in body-plan studies. Such models are relevant to regenerative, developmental, and cancer biology in which cells with distinct properties and morphogenetic target states confront each other in the same tissue.

Clinical and physiological aspects of bruxism and its rational pharmacotherapy

Objective. Clinical-neurophysiological and neuropsychological examination of patients with bruxism was conducted to determine the functional condition of the peripheral and central trigeminal nerve and to justify the combined therapy.Materials and methods. 26 patients (14 women and 12 men) aged 20 to 50 years with complaints and typical neurological symptoms of bruxism were examined. The control group consisted of 30 volunteers in the age from 24 to 35 years, who underwent a comprehensive examination as part of a medical check-up, who did not have severe somatic, neurological or mental diseases and did not have complaints of impaired function of the masticatory muscles. Clinical and neurological, electrophysiological and neuropsychological diagnostic methods were used in the trial. Quantitative sensory testing was performed using TSA II device (Medoc, Israel), and temperature sensitivity thresholds were determined using the Marstok method on symmetrical facial areas according to the Zelder zones. Diagnostics of the functional condition of the masticatory muscles was carried out using a computer neuroelectromyograph M-Test ‘DX-Systems’ and a computer system for analyzingelectromyographic records. Electroencephalography (EEG) was performed using 16-channel computer electroencephalography system. C. D. Spielberger scale adapted by Yu. L. Khanin (C. D. Spielberger, 2010) was used to determine the level of anxiety. The results were processed using Statistica and Microsoft Excel 2015 programs.Results. Patients with bruxism had a high level of personal anxiety, which was found in 73 % of the participants. Determination of the thresholds of cold sensitivity on the faces of patients with bruxism showed a lower threshold of cold sensitivity in the lateral parts and a higher threshold in the oral parts. Electromyography of masticatory muscles showed an increase in the duration of mastication period, a decrease in the masticatory rhythm, a decrease in masticatory efficiency, and irrational functioning of the masticatory muscles of varying severity in the patients of the examined group. Assessment of brain biopotentials showed an increase in the ascending activating effects of nonspecific median brain structures (72 %). The data obtained helped to obtain a comprehensive assessment of functional condition of the trigeminal nerve in patients with bruxism and to justify pharmaceutical therapy aimed at both the muscular apparatus (muscle relaxants) and the peripheral and central parts of the trigeminal nerve (antiepileptic drugs) in combination with a medicine that has a stabilizing effect on the functional condition of neurons and normalization of bioelectric processes in the central nervous system (correctors of metabolism).

Влияние барокамерной гипоксии на эмоционально-двигательное поведение животных

The paper studies the features of orienting-exploratory activity in the conditions of adaptation of the body to pressure chamber hypoxia. White laboratory rats were used in the studies. Simulation of acute hypoxia was carried out in a pressure chamber. In the course of the work, it was found that acute hypoxia leads to inhibition of emotional and motor activity in animals on the 3rd day, depleting energy resources in the nerve cells of the brain of rats. It is known that in the brain, in comparison with the liver and heart, the highest rate of glycolytic reactions is observed, and therefore, within a short time interval, the concentration of lactate in the brain tissue increases significantly. In addition to the accumulation of lactic acid, there is an intensive formation of a number of underoxidized products - reduced pyridine nucleotides, an increase in the content of other organic acids of the Krebs cycle, for example, pyruvic acid. The general acidification of the intracellular environment of neurons is accompanied by a sharp decrease in the activity of cellular enzymes and a violation of their connections with the membrane. Starting from the fourth day, the excitability of neurons responsible for grooming is inhibited, the resistance of the animal organism to acute hypobaric hypoxia increases. The action of low barometric pressure (altitude 6000 meters above sea level) on the fifth and sixth day leads to hypoxic dysfunction of the higher parts of the central nervous system. Thus, the study of the features of the course of bioelectrical processes in the CNS against the background of emerging acute exogenous hypoxic conditions of various origins is of particular importance due to the need to obtain timely and objective information about the severity of functional disorders of brain structures sensitive to hypoxia, as well as to determine the level of their damage.

Влияние барокамерной гипоксии на эмоционально-двигательное поведения животных

The paper studies the features of orienting-exploratory activity in the conditions of adaptation of the body to pressure chamber hypoxia. White laboratory rats were used in the studies. Simulation of acute hypoxia was carried out in a pressure chamber. In the course of the work, it was found that acute hypoxia leads to inhibition of emotional and motor activity in animals on the 3rd day, depleting energy resources in the nerve cells of the brain of rats. It is known that in the brain, in comparison with the liver and heart, the highest rate of glycolytic reactions is observed, and therefore, within a short time interval, the concentration of lactate in the brain tissue increases significantly. In addition to the accumulation of lactic acid, there is an intensive formation of a number of under oxidized products — reduced pyridine nucleotides, an increase in the content of other organic acids of the Krebs cycle, for example, pyruvic acid. The general acidification of the intracellular environment of neurons is accompanied by a sharp decrease in the activity of cellular enzymes and a violation of their connections with the membrane. Starting from the fourth day, the excitability of neurons responsible for grooming is inhibited, the resistance of the animal organism to acute hypobaric hypoxia increases. The action of low barometric pressure (altitude 6000 meters above sea level) on the fifth and sixth day leads to hypoxic dysfunction of the higher parts of the central nervous system. Thus, the study of the features of the course of bioelectrical processes in the CNS against the background of emerging acute exogenous hypoxic conditions of various origins is of particular importance due to the need to obtain timely and objective information about the severity of functional disorders of brain structures sensitive to hypoxia, as well as to determine the level of their damage.

Clinical and neurophysiological correlations in post-Covid‑19 patients and rationale for pathogenetic therapy

Clinical and neurological, neurophysiological, and neuropsychological examination of 50 patients aged 50–65 y. o. with an experience of COVID‑19 infection within the last 3 to 6 months, revealed pathological changes in the central nervous system in the form of cerebrastenic and autonomic disorders, motor disorders, vestibulopathy symptoms, which occurred in various combinations, with astheno-vegetative syndrome as obligate. Cognitive impairments were detected in 26% of patients; the mental fatigability index was 1.055 ± 0.124; a high level of situational anxiety was noted in 35% of patients, and a high level of personal anxiety in 50 % of patients with the experience of COVID‑19. The study of brain biopotentials revealed moderate diffuse changes (18%) and irritative disorders on the part of hypothalamic (69 %) and diencephalic structures (20%). All of the above may indicate that, regardless of the form of coronavirus infection occurred in humans, i. e., latent, mild, moderate or severe, one of the targets of the pathological impact of COVID‑19 virus is the median structures of the brain responsible for autonomic and cognitive functions. Nevertheless, in our opinion, these disorders are associated not with a direct pathological effect, but are mediated mainly by circulatory disorders in the microcirculatory bed due to endothelial damage and are rather functional disorders on the part of the central nervous system. This provides the grounds for the selection of pathogenetic therapy aimed at stabilizing the functional state of neurons, and one of the drugs of choice may be citicoline (Noocyl), the action of which is associated with reinforcing the cell membrane of the neuron and normalizing bioelectric processes.

Можливості омегаметрії в оцінці функціонального стану спортсменок, які спеціалізуються в карате

The purpose of the study was to investigate the peculiarities of changes in the general functional condition of the brain of highly qualified female athletes specializing in karate, in terms of omega potential indicators and to assess the adaptive capability of the central nervous system during physical load. Materials and methods. The study involved 14 highly qualified female athletes aged 17-22 years – representatives of the Odessa Regional Karate Federation. Determination of the dynamics of infraslow bioelectrical processes of the brain, namely omegapotential, was carried out according to the method of O. G. Sychov et al. (1980) at rest, after performing a test in one squat, with dosed physical load in a closed cycle (with reverse) and during the recovery period after exercise. Results and discussion. According to the results of anthropometric and physiometric measurements, the height of the studied girls specializing in karate, on average, was 164.43±0.86 cm, and body weight – 56.36±2.23 kg. The thorax circumference at rest was 84.86±1.57 cm, at the inhale – 89.57±1.49 cm, at the exhale – 82.5±1.57 cm. The average value of vital capacity of the lungs was 3457.14±101.93 ml, wrist dynamometry – 23.36±1.02 kg, back dynamometry – 63.57±3.53 kg. The analysis of the results of the study of infraslow brain processes showed that in the initial state the omega potential value ranged from 10 to 59 mV, which indicated the optimal baseline level in most female athletes before exercise. In the state of relative rest, the average omega potential values (21-40 mV) were found in 79% of the surveyed girls, high (41-60 mV) and low (up to 20 mV) – in 14% and 7%, respectively. The results of study of omega potential dynamics when tested in one squat indicate isolated cases of adequate responses and optimal activation of adaptive systems of the body to the functional load. In most female athletes, the violation of chemo-metabolic, neurohumoral and hormonal processes were observed after performing the test of one squat. The peculiarities of omega-potential dynamics, which were noted during the performance of dosed physical load in a closed cycle (with reverse), indicate a gradual decrease in the studied indicators relative to the initial state during the performance of bicycle ergometric load, especially during the period of reverse (heart rate = 150-155 beats / min) and at the end of testing. At the same time, the depth of shifts also increased, which reflects the significant tension on the central nervous system and other body systems of female athletes in response to physical load. After performing exercise at the 2nd and 5th minutes of rest, no recovery of infraslow bioelectrical processes to the initial level was recorded, which indicates the development of overstrain of adaptive mechanisms. Conclusion. Testing of qualified female athletes specializing in karate, using a functional test conducted in one squat, according to the data of average group indicators of omega potential revealed a violation of chemo-metabolic, neurohumoral and hormonal processes. The study of individual data shows that in most of the surveyed there are various violations of these body systems. The dynamics of infraslow bioelectrical processes in the brain of female athletes during testing using bicycle ergometric load in a closed cycle (with reverse) is characterized by a steady decrease in omega potential throughout the test, which reflects the overstrain of regulatory mechanisms and deep mobilization of functional capabilities. The restoration of the level of omega potential to the initial level at the 5th minute of the post-exercise period does not occur

EEG-based musical neurointerfaces in the correction of stress-induced states

ABSTRACT Chronic action of work-related and background stresses causes a disruption of coping mechanisms and may first lead to functional disorders, and then develop into serious stress-related diseases. This generates a need for timely correction of stress-induced functional disturbances. Prior research has shown promise in closed-loop EEG feedback systems to alter patients’ mental states induced by stress. The present study aims to assess the effects of stress suppression using a single (music) or double (music+video) feedback from the patient’s EEG. In one of three experiments, 18 stressed volunteers were presented with classical music without feedback (control). In the other two experiments, either a single feedback was used, where music loudness varied in strict accordance with the current amplitude of the patient’s EEG oscillator, or a double feedback, in which the described music signals are supplemented by rhythmic light stimuli generated from the patient’s EEG. A significant increase in alpha EEG power, accompanied by positive emotional reactions and shifts in the functional state of the participants were observed only in the presence of the feedback from the EEG. Doubling the feedback from human EEG leads to increased effectiveness of neurointerfaces due to resonant interaction between rhythmic sensory stimuli and bioelectric processes of the human brain.

APPLICATION OF THE ELECTROSTATIC FIELD OF ELECTRET IN THE SURGICAL TREATMENT OF PATIENTS WITH GONARTHROSIS

A significant role in the pathogenesis of osteoarthritis (OA) belongs to the violation of the natural bioelectrogenesis of bone and cartilage tissue. External correction of bioelectric processes in joint structures by means of an electrostatic electret field is pathogenetically justified and has practical significance in the surgical treatment of degenerative diseases in orthopedics. The article presents an analysis of the results of surgical treatment in 45 patients with stage 2-3 gonarthrosis aged 30 to 70 years using electretes based on tantalum oxide. The results of treatment were evaluated based on the dynamics of the clinical and functional index WOMAC, data from clinical and radiological studies. The positive effect of the electrostatic field of electret in OA was manifested by a decrease in clinical symptoms of the disease, increased functional activity of patients, restraining degenerative changes in joint structures, and improving the quality of daily life during the follow-up period. The positive effect of the electrostatic field of electret is based on the activation of repair of bone-cartilage structures, which allowed to slow down the degradation of subchondral bone and articular cartilage in gonarthrosis.Clinical use of electret stimulators significantly effectively improves joint function which reduces the risk of progression of degenerative changes in the joint especially in patients with the second stage of the disease. The clinical use of electronic stimulators significantly effectively improves joint function which reduces the risk of progression of degenerative changes in the joint especially in patients with the second stage of the disease.The use of electretes in the treatment of patients with stage 3 gonarthrosis can improve the function of the joint for a long time more (2 years) and postpone the endoprosthesis operation.

Network Thermodynamical Modeling of Bioelectrical Systems: A Bond Graph Approach.

Interactions among biomolecules, electrons, and protons are essential to many fundamental processes sustaining life. It is therefore of interest to build mathematical models of these bioelectrical processes not only to enhance understanding but also to enable computer models to complement in vitro and in vivo experiments. Such models can never be entirely accurate; it is nevertheless important that the models are compatible with physical principles. Network Thermodynamics, as implemented with bond graphs, provide one approach to creating physically compatible mathematical models of bioelectrical systems. This is illustrated using simple models of ion channels, redox reactions, proton pumps, and electrogenic membrane transporters thus demonstrating that the approach can be used to build mathematical and computer models of a wide range of bioelectrical systems.

Bioelectric heart processes in healthy men at different levels of acute normobaric hypoxia

The aim was to study cardiac bioelectric features across different levels of acute normobaric hypoxia (ANH) in healthy young men. Methods: We studied cardiac functions in response to exposure to ANH of mild (14.5 % O2) and medium (12.3 % O2) degrees for 20 minutes among 30 and 29 young men, respectively. Results. With mild and medium degree of ANH, SpO2 decreases to (91.6 ± 4.2) % and to (78.2 ± 5.2) %, respectively. An initial increase in the P1II wave was common for all ANH exposures. On average, during the period of mild ANH, the total BAL and BAR of the heart compartments decreased, only at the beginning the RR and QT intervals decreased, and in the end QT increased. Medium ANH was associated with more pronounced changes in ECG characteristics. On average, during the ANH period of 12.3 % O2, the RII wave (by 0.078 mV, p < 0.001), T1II (0.074 mV, p < 0.001), BAL (0.26 mV, р < 0.001) and BAR (at 0.12 mV, p < 0.001) of the heart decreased, RR intervals (at 100 ms, p < 0.001), QT (11 ms, p < 0.001), and Pc, PQc, QRSc, QTc increased. Correlations between QT deviations and SpO2, СО, SVR, VIK increased. For ANH of 14.5 % O2, the factor "positive chronotropic effect" dominated in the general structure of the ECG, while for 12.3 % O2 it was "chrono-inotropic conjugation". Conclusions. Changes in ECG parameters seem to be more pronounced in exposure to moderate than mild ANH. Possible extracardiac and myogenic regulation mechanisms in the organization of heart bioelectric processes with a mild and medium degree of hypoxia are proposed in the paper.

Когнитивный вызванный потенциал Р300 у школьников 16–17 лет, проживающих в регионах Арктической зоны РФ

Living in adverse climatic and geographical conditions of the Arctic zone of the Russian Federation requires mobilization of the adaptive mechanisms of the central nervous system in humans. The parameters of the event-related potential P300 serve as indicators of brain bioelectric processes associated with the mechanisms of information perception and processing. This study aimed to establish the parameters of the event-related potential P300 in 16–17-year-old schoolchildren living in different regions of the Arctic zone of the Russian Federation based on a comparative analysis. The auditory event-related potential P300 was evaluated in subjects living in the Nenets Autonomus Okrug (NAO), Yamalo-Nenets Autonomous Okrug (YNAO) and the Arkhangelsk Region (AR). P300 latency and amplitude were recorded by the Encephalan-131-03 electroencephalograph (Medicom MTD, Russia) in the frontal (F3, F4), central (C4, C3), parietal (P3, P4), mid-temporal (T3, T4), and anterior temporal (F7, F8) areas of the brain using the oddball method. In schoolchildren living in AR and YNAO, the amplitude-latency parameters of P300 did not differ significantly. Subjects living in NAO, the majority of whom are representatives of the indigenous peoples of the North (the Nenets), had a longer P300 latency than their peers from other regions. Р300 amplitudes in schoolchildren from all the regions under study were statistically identical. The author comes to the conclusion that longer information processing time, according to the P300 data, reflects the adaptive psychophysiological characteristics of the population with a long historical experience of living in the North.

The experience of using iodine-bromine baths and ozone therapy at the stage of health resort treatment of patients with chronic cerebral ischemia

Background. Treatment of chronic cerebral ischemia should be aimed both to the main etiological factor and to the pathogenetic mechanisms of cerebral ischemia and hypoxia. The action of ozone therapy is characterized with a multilateral positive effect on the main aspects of chronic cerebral ischemia pathogenesis, such as chronic cerebral hypoxia, impaired microcirculation, rheological disorders, and activation of lipid peroxidation. The use of iodine-bromine baths in chronic cerebral ischemia has been proved to be accompanied by an improvement in cerebral circulation, normalization of the brain bioelectric processes, an initially impaired condition of the autonomic nervous system, and an increase in the level of adaptive capabilities of the body.
 Aim: to develop effective pathogenetically substantiated methods for the combined use of iodine-bromine baths and ozone therapy in patients with chronic cerebral ischemia to increase the effectiveness of health resort treatment.
 Methods. In accordance with the tasks set in the work, 90 patients with chronic cerebral ischemia of the degree 1, who were randomized into three treatment groups, were examined and treated. Patients of the control group (n = 30) received iodine-bromine baths, patients of the comparison group (n = 30) received ozone therapy, patients of the main group (n = 30) received iodine-bromine baths and ozone therapy. Examination of patients included Doppler ultrasound, electroencephalography, rheoencephalography, сardiointervalography, lipid metabolism studies, fibrinogen content studies.
 Results. As a result of treatment, the improvement of clinical symptoms and the normalization of biochemical and neurophysiological parameters were noted in patients of all treatment groups. Overall efficiency (improvement and significant improvement) was 53.3% in the control group, in the comparison group it was 63.3%, and 73.3% in the main group.
 Conclusion. The authors proved the practicability of rehabilitative treatment of early forms of vascular diseases of the brain at the stage of sanatorium and resort rehabilitation, which is due to significant compensatory reserves and high plasticity of the structural and functional formations of the brain with preserved ability to develop nonspecific elements of the nervous tissue and restore reversibly damaged structures.

Bio-electrical engineering: a promising frontier for synthetic biology

What do the following have in common? The production of methane gas from farm waste; toilets at a music festival, lit with LED lights; a bacterial biofilm that is on the brink of starvation. All of these involve microbes that are making use of bio-electrical processes. Though it is difficult to define the limits of what can be called bio-electrical, these processes are typically responding to or creating a current or voltage, with the electrical effects extending beyond the limit of an individual cell. In the examples above, current is flowing between organisms of different species or between an organism and an abiotic material, or voltage changes are being sensed and propagated across a colony of cells. Our appreciation of the extent of electrical phenomena in microbial biology has seen a recent revival, with studies revealing not just the variety of bioelectrical processes that exist but also defining the molecular mechanisms responsible. Now, we can begin to apply the approaches and techniques of synthetic biology. By re-engineering natural systems, we can hope to improve our understanding of how their components function and repurpose them for exciting biotechnological applications.

STATUS OF BIOELECTIC MYOCARDIAL ACTIVITY IN 400 M DISTANCE RUNNERS DEPENDING ON THE SEX

Introduction. The method of electrocardiography deeply reflects the essence of bioelectric processes in myocardium, characterises deviation from the norm state, demonstrating locality and specificity of pathogenic changes, and makes it possible to estimate functional readiness of both cardiovascular system and the organism on the whole, without applying complicated and costly methods of apparatus control.The aim is to study bioelectric activity of myocardium in 400 m distance runners of a single qualification depending on the sex.Methods. At the beginning of the preparatory period of the training process, 131 400 m distance runners (60 women and 71 men) in the age from 13 to 30 years, qualification from III level to the international class master (MSIC) underwent an electrocardiographic test.Research results and conclusions. Bradycardia was less common in women (38.3 %) than in men (57.7 %). Changes in ECG were recorded at the same frequency in women (43.3 %), and men (56.3 %). Of the total number of ECG changes, there were statistically more men with changes in the terminal part of ventricular complex (VC) (19.2 % vs. 10 %), SEVR (55 % vs. 34.6 %) and atherosclerosis (10 % vs. 3.9 %). The analysis of changes in ECG in the form of SEVR and IRBBB in athletes of both sexes showed the following: SEVR is found in 23.7 % and IRBBB - in 13 %. After exercise in the form of a submaximal test PWC170 in athletes with atherosclerotic rhythm and changes in the terminal part of the ventricular complex, normalization of ECG was observed.Conclusions. In runners with CLC syndrome and BPBLBB, according to echocardiography, pathological changes were not detected, and the presence of IRBBB and SEVR should be considered as peculiarities of the ECG for this category of athletes.

Progenitor Hyperpolarization Regulates the Sequential Generation of Neuronal Subtypes in the Developing Neocortex

During corticogenesis, ventricular zone progenitors sequentially generate distinct subtypes of neurons, accounting for the diversity of neocortical cells and the circuits they form. While activity-dependent processes are critical for the differentiation and circuit assembly of postmitotic neurons, how bioelectrical processes affect nonexcitable cells, such as progenitors, remains largely unknown. Here, we reveal that, in the developing mouse neocortex, ventricular zone progenitors become more hyperpolarized as they generate successive subtypes of neurons. Experimental invivo hyperpolarization shifted the transcriptional programs and division modes of these progenitors to a later developmental status, with precocious generation of intermediate progenitors and a forward shift in the laminar, molecular, morphological, and circuit features of their neuronal progeny. These effects occurred through inhibition of the Wnt-beta-catenin signaling pathway by hyperpolarization. Thus, during corticogenesis, bioelectric membrane properties are permissive for specific molecular pathways to coordinate the temporal progression of progenitor developmental programs and thus neocortical neuron diversity.

Analysis of the transmembrane potential of embryos exposed to action of nickel, cobalt, tin and zinc

Germ cells of aquatic organisms are complex systems whose growth and development depends on many factors, one of which is the composition of the aquatic environment. We used parameters in our analysis from aggregate data available from published literature. They are data of the transmembrane potential of the germinal cells of Misgurnus fossilis (Linnaeus, 1758) at the development stage from 180th to 360th minutes. Embryos were incubated in an environment with nickel, cobalt, tin, and zinc ions and without them. Plotted lines of the transmembrane potential were digitized and calibrated at intervals of 10 minutes. Rows of numerical values of the transmembrane potentials were obtained. These rows were used for calculation of autocorrelation and cross-cross-correlation functions. It was established that the transmembrane potential describes nonperiodic and quasi-periodic oscillations. The higher statistically significant values of the autocorrelation coefficients were observed in the first lags. Autocorrelation analysis indicates that the periods of oscillations of the transmembrane potential increase with the action of nickel, cobalt, tin and zinc on the germ. The phenomena and processes that occur in the germ cell are well reflected at the initial stages of the auto-correction and are lost when the magnitude of the lag increases. The degree of similarity of transmembrane potentials with the help of cross-correlation analysis is quantitatively characterized. The distribution of fluctuations of cross-correlation functions with complex dynamics, which arise with time shifts both in the forward and reverse directions, were established. It is established that for large values of time shifts, the cross-correlation coefficient is a low-informative indicator, since information about the influence of the factor on the living system is lost. A graph for a given time shift was constructed. The connection between the nodes is the magnitude of the cross-correlation coefficients between the vapor of the transmembrane potentials, which indicate the degree of similarity of the bioelectric processes. Graphs will be used for qualitative and quantitative study of system dynamics. The obtained results confirm the existence of a close relationship between environmental nickel, cobalt, tin, and zinc and the oscillation of transmembrane potential during early embryogenesis.