Vol 43, No 1 (2017)

The aim of this study was to investigate the state of binocular vision in first-year schoolchildren with high binocular visual acuity. The results have shown that only 5.1% of these children had normal binocular vision, whereas 25.7% of them had moderate impairments, and 67.9% had severe plus moderate impairments in binocular vision. Significant intergroup differences between schoolchildren with learning difficulties in reading and children with normal reading have been detected in the mean indicators for the distance of near-point of convergence (p < 0.001) and the visual behavior symptoms that confirmed binocular dysfunctions (p < 0.002).

Using studies of the right and left hemisphere’s specialization for positional and vector coding, we analyzed the errors made by right- and left-handers while reproducing sequences of right and left hand movements in a task that activates vector coding by changing the order of movements in memorized sequences. The task was performed first with one hand (starting) and then with the other (continuing). Both right- and lefthanders were found to use information about previous movements of the starting hand only when the dominant hand was starting. After changing the hand, right-handers used information about previous movements of the continuing hand, while left-handers did not. The results were compared with data from earlier experiments wherein positional coding was activated. The comparison showed that vector coding was predominantly involved in memorizing sequences of movements made by the dominant hand, while positional coding was used in the case of the opposite hand in both right- and left-handers. Patterns of errors after changing the hand differed between right- and left-handers, and the conclusion was made that skills are transferred in different ways in right- and left-handers, depending on the type of coding.

Age-related features of spinal inhibition in the regulation of voluntary movements in men were studied. It was found that presynaptic and nonreciprocal and reciprocal inhibitions of the flexor of toes during voluntary movements were less intense than inhibition during relative muscle rest in subjects of all age groups. This results from the age-related features of supraspinal excitatory and inhibitory effects on Ia and Ib spinal interneurons, which change the mechanism of spinal inhibition of voluntary movements as the organism develops. In boys 9–12 years of age, execution of voluntary movements is accompanied by the lowest presynaptic inhibition of Ia afferents and the most pronounced increase in nonreciprocal and reciprocal inhibition of α-motoneurons in the flexor of toes, compared to the other age groups. Execution of voluntary movements by boys 14–15 years of age leads to an increase in presynaptic inhibition of Ia afferents and the most pronounced decrease in reciprocal and nonreciprocal inhibition of spinal α-motoneurons of the flexor of toes. By the age of 17–18 years, the mechanism of nonreciprocal inhibition of α-motoneurons of the flexor of toes during voluntary movements is similar to that in adolescents aged 14–15 years. The definitive level of presynaptic inhibition of Ia afferents and reciprocal inhibition of α-motoneurons of the flexor of toes during voluntary movements is reached by 17–18 years.

The present work investigated the effect of different breathing strategies performed with and without body immobilization on postural performance. Sway amplitude and mean velocity of center of pressure displacement in the anteroposterior and mediolateral planes were assessed by the force platform in 48 healthy volunteers. Balance was estimated during quiet breath, inspiratory, expiratory breath holding and hyperventilation with and without immobilization of the neck, trunk, hip, and knee joints. In general, restriction of body mobility caused a reduction of the postural stability in anteroposterior plane, while mediolateral body sway decreased. Our results imply that body immobilization reduced the ability to compensate respiratory disturbances in the anteroposterior direction and, on the contrary, facilitated mamtaining balance in the mediolateral plane.

We propose a model for the human cardiovascular system that describes the cardiac cycle, the autonomic regulation of heart and vessels, the baroreflex, and the formation of blood pressure. The model also allows for the influence of respiration on these processes. It has been found that an allowance for nonlinearity and insertion of a loop for the autonomic control of mean blood pressure (having the form of selfoscillating time-delay system) enables obtaining model signals with statistical and spectral characteristics that are qualitatively and quantitatively similar to those for experimental signals. The model reproduces the phenomenon of synchronization of the loop for mean blood pressure regulation with a basic frequency of approximately 10 s by the signal of respiration.

The prevalence of obesity has increased worldwide and represents a major public health concern. Obesity is often associated with an increase in urinary albumin excretion and impaired insulin sensitivity. Whilst it is clear that exercise is beneficial in terms of improving insulin sensitivity, the optimal exercise prescription in different cohorts is still unknown, hence the recent increase in studies investigating high versus moderate intensity interventions. It is also unclear what effect acute bouts of exercise may have on microalbuminuria, a marker which is more commonly being utilized for screening and prognosis of diabetes and cardiovascular disease.

The last two decade discoveries shift the accent from the consideration of human chorionic gonadotropin (hCG) as a hormone that controls progesterone production by corpus luteum cells to a powerful paracrine regulator that, in the tandem with its hyperglycosylated analog (h-hCG), induces successful implantation and coordinated dialog between blastocyst and uterine tissues. The ability of hCG and h-hCG to interact with TSH receptor and TGF-beta-RII, respectively, significantly extend the spectrum of processes controlled by these molecules. Differences between intracellular pathways of signal transduction between hCG and LH mediated by the same receptor (LH/hCG-R) impugn the unity of their effector mechanisms, which was previously considered as obvious. The paracrine properties of hCG include the control of fusion of trophoblasts into syncytiotrophoblasts, angiogenesis, immunity regulation, and endometrium predisposition to implantation. Angiogenesis is associated with LH/hCG-R expressed on mural cells of uterine spiral arteries as well as induced secretion of soluble VEGF form by endometrial cells. hCG regulates the ratio between different types of T-helper cells in maternal organism at the initial gestation stage determining a high level of Th2 cells. hCG supports local immunotolerance, functioning as a chemoattractant for T-suppressors (T-Treg) and an apoptotic factor for T-lymphocytes. Endometrial susceptibility arises from the activation of osteopantin secretion and the decline of mucin secretion by epithelial cells. h-hCG affects the same tissues as hCG, functioning as a paracrine agent regulating multiple cascades of cytokines. h-hCG plays the key role in the trophoblast invasion into the uterine decidua as a result of gelatinase secretion by these cells. The degree of the angiogenic effect of h-hCG is compatible with that of hCG, but its signal transduction is mediated by the TGF-beta signal transduction pathway that stimulates mural cell proliferation. h-hCG acts as a mitogen on NK-cells and is able to activate them and direct to angiogenesis maintenance. In this article, we attempted to elucidate the most important discoveries about the role of hCG and its hyperglycosylated analog, both accomplished and still upcoming.

This paper analyzes the cellular and humoral components of the immune system in athletes who were born, lived, and trained under the conditions of the middle Ob region (Khanty-Mansi Autonomous Okrug—Yugra, KhMAO–Yugra). The main group included young men and women, who were engaged in cross-country skiing (12 men and 10 women) and volleyball (11 men and 10 women). The control group (regional norm) included ten men and ten women, who were born and currently lived in KhMAO–Yugra and did not do any sports on a regular basis. The age of the subjects ranged from 19 to 22 years. It was found that the parameters of cellular and humoral immunity differed slightly with respect to the control group. A significant decrease in the total count of leukocytes, neutrophils, and lymphocytes was observed in men and women, who were born, lived, and trained under the conditions of the middle Ob region; in addition, a decrease in the parameters of humoral immunity (B cells and IgA) was also observed in male skiers. It was found that the total leukocyte count, the level of B cells, and the IgG concentration in men who live in the middle Ob region and do not do any sports is higher than that in women of the same group.