Human Physiology

On the basis of comprehensive neurophysiological examination, we tried to analyze the systemic organization of functions in Parkinson’s disease in terms of the theory of functional systems. Study of the specificity of internal neurophysiological organization helps to find a high level of internal tension and limitation of functional reserves in patients with Parkinson’s disease, including those with the rigid form and long duration of the disease. The possible predominance of homeostatic response programs in Parkinson’s disease is discussed.

Electroencephalogram (EEG) patterns and the process of visual memory were studied in 27 patients with extracerebral tumors occupying mediobasal regions of the right and left hemispheres. The degree of involvement of the hippocampus (HP) in the pathological process was assessed based on neuroimaging (magnetic resonance imaging, MRI) and morphometric data. The predominant concentration of irritative–epileptiform signs in the affected hemisphere, as well as the presence of atypical α-rhythm episodes in the area of tumor projection, were treated as the EEG markers of tumor compressive effect on the HP. Signs of nonidentical involvement of the right and left HP in the pathological process were found in the form of the predominance of irritative signs in the left hemispheres of patients from the studied group as a whole. Equivalent dipole sources (EDSs) of atypical α-rhythm were more associated with the hippocampal structures compared to irritative EEG patterns. Neuropsychological testing of visual memory did not reveal considerable disturbances in memory processes at this stage of the disease.

The relationship between the expression level of Ca2+-ATPase (SERCA2a) and calsequestrin (CASQ2) and the structural and functional characteristics of the heart of patients with permanent atrial fibrillation was studied. The study included 40 patients with persistent atrial fibrillation. Patients underwent radiofrequency ablation (RFA), during which a biopsy of myocardial tissue was taken from the left ventricle. Intracardiac hemodynamic parameters were recorded from standard echocardiographic positions. The content of SERCA2a and CASQ2 proteins in the myocardium was determined by immunoblotting. Correlation was found between the level of SERCA2a and CASQ2 in the myocardium and the size of the left atrium. Patients with higher values of end-diastolic and end-systolic heart volumes had high levels of SERCA2a. Lower rates of early (peak E) and late (peak A) diastolic filling of the left ventricle were associated with high SERCA2a expression. The level of expression of the calcium handling proteins Ca2+-ATPase and calsequestrin was associated with the structural and functional parameters of the heart of patients with permanent atrial fibrillation.

Các thay đổi trong các tham số chuyển hóa của những người khỏe mạnh đã được nghiên cứu trong các khóa huấn luyện mô phỏng lặn kéo dài từ 4 đến 21 ngày với các hỗn hợp khí áp suất cao khác nhau bao gồm normoxic (oxy-helium), hyperoxic (oxy-nitrogen-helium), và các hỗn hợp khí chứa argon với các nồng độ oxy khác nhau. Nồng độ máu của các cơ chất chính và hoạt tính của các enzyme đã được đo bằng phương pháp quang phổ. Trong hầu hết các trường hợp, các tham số lâm sàng và sinh hóa của máu vẫn nằm trong giới hạn bình thường và cho thấy sự biến đổi cá nhân đáng kể. Các lần lặn sâu mô phỏng kéo dài (>200 m) đã dẫn đến những thay đổi trong chuyển hóa lipid thể hiện dưới dạng gia tăng nồng độ triglycerides, low-density lipoproteins, và axit béo không bão hòa đa trong huyết tương. Không có thay đổi đáng kể nào được phát hiện trong các lần lặn 70 m được thực hiện theo bảng điều trị tái nén với sự sử dụng hỗn hợp khí chứa helium hyperoxic. Ngược lại, sự tiếp xúc kéo dài với hỗn hợp chứa argon normoxic ở áp suất 5 msw đã gây ra sự gia tăng đáng kể nồng độ triglycerides, cholesterol toàn phần và glucose trong máu, cũng như một sự gia tăng nhỏ trong hoạt tính của một số enzyme mô. Ở cùng áp suất đó, các hỗn hợp khí hypoxic oxy-nitrogen-argon và oxy-nitrogen không ảnh hưởng đến hầu hết các tham số lâm sàng và sinh hóa được kiểm tra. Tuy nhiên, ở một số người, chúng làm tăng chỉ số atherogenicity, nồng độ triglycerides, và hoạt tính của lactate dehydrogenase và alkaline phosphatase. Việc không có bất kỳ thay đổi bệnh lý nào trong các tham số lâm sàng và sinh hóa của máu cho thấy rằng cả hai hỗn hợp khí đều an toàn và có thể được sử dụng trong các buồng áp suất. Những thay đổi từng đợt trong chuyển hóa lipid và hoạt động enzyme được quan sát ở những người khỏe mạnh khi tiếp xúc với các hỗn hợp khí chứa helium và argon có thể được hiểu là một chức năng gan có thể hồi phục do áp lực cao. Độ lớn của những thay đổi trong các tham số chuyển hóa lipid trong máu được xác định bởi độ lớn của áp suất vượt mức và thời gian tiếp xúc.

The EEG was recorded in 12- to 13-year-old adolescents with attention deficit hyperactivity disorder (ADHD). During the EEG recording, the subjects performed an attention test. Pairs of tone stimuli in the combinations low–low and low–high were presented in random order with equal probabilities with intervals of 2.3 s. Subjects had to press a button as soon as possible in response to low–low tone pair presentation (a go trial) and not to press the button when a pair consisting of low and high tones was presented (a no-go trial). On the basis of the results of the test performance (the numbers of omissions and false alarms), the subjects were divided into three groups characterized by the degree of severity of the attentional disorder. The evoked potentials in go and no-go trials were detected individually for the subject groups and each derivation. The components N1, N2, P2, P3-go, and P3-no-go were identified in the evoked potentials. These components had different latencies and were differently localized over the head surface. Only the amplitudes of P3-go and P3-no-go in the subjects were statistically significantly correlated with the severity of the attentional disorder.

Forced expiratory wheezes (FEWs) are used for the diagnosis of bronchial obstruction; however, there is no clarity about the mechanisms and possible localization of their formation. The aim of the study was to clarify the sites of FEW formation at bronchial levels in different types of dynamic compression. The peak frequencies of the mid- (400–600 Hz) and high-frequency (more than 600 Hz) FEWs of the maximum power and the flow rate at the mouth were measured in a sample of 85 healthy male volunteers whose ages varied between 16 and 23 years. Strouhal coefficients were calculated for various bronchial tree levels according to Weibel’s morphometry. It is shown that, for FEWs formed by vortex shedding with Strouhal coefficients 0.2–0.3, the trend is to shift their formation zone to the proximal region with an increase in the degree of dynamic compression of the airways. For the most reliable estimates of dynamic compression, the main region of formation of mid-frequency FEWs is the area of exit of the intrathoracic portion of the trachea into its outer part and bifurcation of the trachea, while the most probable formation zone of early high-frequency FEWs is bifurcations of the primary bronchi and the trachea.

The susceptibility of T cells of healthy subjects during 21 days of “dry” immersion (DI) to MSC-mediated immunosuppression was investigated in vitro. During DI, the expression of the late activation (HLA-DR) marker and paracrine activity were increased in PHA-stimulated T cells. Proliferation was decreased, and Th1/Th2 balance was shifted towards Th1. MSCs possessed immunomodulatory properties in co-culture with T cells of healthy subjects in background, as well as during DI suppressing late activation, proliferation and shifting the balance of cytokines to Th2. However, the antiproliferative effect of MSCs was not always detected and depended on the initial response of T cells to a mitogen. In addition, the ability of MSCs to “smooth” the effects of “dry” immersion was demonstrated.

The influence of the drug dilantin on the mental state of humans in the presence of objective neuroticizing factors (restriction of freedom and the concomitants) was studied. A positive effect of the drug on the emotional state of prisoners, namely, decreases in the levels of reactive and personal anxiety and depression, as well as in the probability of the development of neurotic disorders, was shown.