The lymphatic vascular system is a highly organized network of structurally and functionally connected specialized lymphatic vessels of various sizes and lymph nodes that perform metabolic and transport functions. Lymph is a blood plasma filtrate that comprises antigen-presenting cells and lymphocytes. Via lymph, excess fluid and extravasated proteins are removed from the tissues. The lymphatic system supports an extracellular fluid homeostasis that is favorable for optimal tissue functioning by removing substances that result from metabolism or cell death, as well as optimizing immunity against bacteria, viruses and other antigens. Although the lymphatic vasculature is not formally considered part of the immune system, it is crucial for the traffic of antigens and immune cells. In addition, lymphatic endothelial cells can supply antigens and express factors that modulate immune responses. After an inflammatory stimulus, endothelial cells produce chemokines, which recruit immune cells to the lymph nodes. Unlike the circulatory system with a centralized pump, the movement of lymph through the network of lymphatic vessels is provided by forces that stimulate the initial formation of lymph in the tissues and the ability of the lymphatic vessels and nodes to rhythmically contract, providing increased pressure and lymph movement in the proximal direction. Since the metabolic rate in various organs and tissues varies significantly depending on the functional state of the tissue, the blood flow through the tissue and the amount of lymph formed also change significantly. The lymphatic vasculature has several circuits for regulating lymph flow. This review provides a comprehensive overview of the important results obtained over the past century and discusses the molecular and physiological control of the transport function of lymphatic vessels and nodes.

Introduction. The knowledge of lymph efflux and its features seems to be significant for diagnosis and treatment of cancer diseases. The purpose of this paper is exploration of the lymph efflux from lungs by infrared fluorescence in patients with lung cancer. Materials and methods. Indocyanine green (ICG) was injected peritumorally during the lung resection in 92 patients with non-small cells lung cancer (NSCLC). We managed to reliably visualize ICG fluorescence in at least 1 regional lymph node (LN) of the lung root or mediastinum in 70 patients (76%), they are included in the study. Results. The accumulation of ICG was detected in 63% of patients in the LN of the root and mediastinum, in 27% of cases - in the mediastinum only, in 10% of patients - in the hilar nodes only. There was no correlation between lesion of lymph node group and ICG injection in any lung lobe. Conclusions. The lymph efflux from different lung lobe is variable in patients with lung cancer. The lymph can run toward the nodes of both lung root and mediastinum.

Relevance. Not only microvasculature and derma are involved in the involution processes. The involution also effects on the all components of skin resulting in its function and structure alterations. By this reason we can speak about the disturbances of microcirculatory tissue system. The aim of this work was a comparative assessment of cosmetic equipment (PDL, IPL), mesotherapy and external skin care therapy in cosmetology patients by the functional state of microcirculatory tissue system of facial skin. Materials and methods. 62 women after mesotherapy, equipment cosmetology and professional external therapy of facial skin were involved in the exploration. We used the laser Doppler flowmetry and laser fluorescence spectroscopy for assessment the microcirculation, lymph flow and the oxidative metabolism coenzymes. Results. Peripheral blood flow did not change significantly, as the lymph flow rate in the control and experimental groups. Nutritional blood flow increased significantly to 12,11 [11,17; 14,17] and 11,88 [10,59; 12,28] in patients after injection and external therapy (p<0,001 and p=0,010, respectively). The NADH fluorescence amplitudes significantly decreased in all groups compared with the control (p<0,001, p=0,002, p=0,008), and FAD decreased only after injection therapy (p=0,022). Conclusions. The injections for correction the age-related skin changes improve the nutrition and normalize tissue metabolism. Our results can be useful in comparative assessment of different ways of the age-related skin changes cosmetic treatment.

The microcirculatory disfunction plays an important role in the development of pneumonia, determining the clinical course and development of complications. The purpose of the study is the assessment of lung microcirculation disturbance on the different stages of the community-acquired pneumonia and distinguishing it from a post heart attack pneumonia. Materials and methods. 135 patients were radiologically explored. They were admitted to the radiological department with inflammatory signs for the assessment of microcirculation disturbances caused by the pneumonia. We investigated the obtained results. Results. The paper elucidates the stages of community-acquired pneumonia by the results of radiological exploration. In the absence of respiratory diseases, the alterations of lung parenchyma structure were caused by pleural effusion (r=0.71) and pneumonic infiltration zones (posterior parts of the lungs (0.74) and lingular segments (r=0.64)). The microcirculatory disturbances were elicited and counted in automatic mode. The residual alterations were reliably more often observed in the patients with chronic bronchitis. The level of D-dimer was not pathognomic but it was reliably higher in the patients with the PATE (p<0.05). Conclusions. The ambiguous interpretation of disk-shaped atelectasis, avascular sites and areas of pneumonic infiltration of lung tissue with MSCT, requires the SPECT or combined SPECT-CT studies allowing to detect clear triangular microcirculation defects characteristic of pulmonary embolism. The site of inflammatory infiltration effects on the appearance of pulmonary fibrosis. So, the zones of fibrosis can be found in the upper lobes, posterior parts of the lungs and lingular segments reliably more often. The technique for automatic processing of radiological lung exploration allows to get the quantitative assessment the microcirculatory disfunction and the lack of perfusion. It is essential for evaluation of the pathology dynamics and severity and for assessment of the treatment efficiency.

Aim. In the present study we evaluate the amplitude-frequency spectrum patterns of the relatively healthy individuals using the laser Doppler flowmetry with simultaneous registration of micro-flow in five points and application of orthostatic sample. Materials and methods. 144 healthy volunteers (69 women, 45 men) from 18 to 40 years old (the average age is 26±6) in a good physical condition were included in the exploration. The mobile flowmeters LAZMA-PF (Russia) was used to record blood flow. All patients were carried out by laser Doppler flowmetry with the use of orthostatic test. Measurements were recorded at the same time in five points (medial overhead areas, inner surface of forearms, overhead area). Results. We observed typical patterns of amplitude-frequency spectrum in the regions of arcs of aorta and upper hollow vein, as well as descending aorta and lower hollow vein. The changes are due to the body position alteration. By the monitoring blood flow in the upper extremity and the supercilium regions the spectral harmonic of the myogenic range (0.047–0.145Hz) dominated in the clinostatic position and the harmonic of the neurogenic range (0.02–0.046 Hz) was less noticed. In the signal spectrum obtained from the lower limbs the harmonic of the neurogenic range (0.02–0.046 Hz) dominated and the harmonic of the myogenic range (0.047–0.145Hz) was less noticed. In the orthostatic position in the region of upper extremities and supercilium, the harmonic amplitude of the neurogenic range increased regarding to the amplitude of the myogenic spectrum, and in the region of lower extremities, the harmonic amplitude of the myogenic range increased regarding to the amplitude of the neurogenic range. Conclusions. Using of the several sensors in the different body parts by the same time is improving the technique relevance. The healthy volunteers showed the typical patterns of slow wave part of ACS in the upper and lower parts of the body in clinostatic and orthostatic positions. The body position changing is reversing the patterns in the upper and lower body parts. Getting the postural test allows to assess the integrity of regulation mechanisms of microcirculation. The method used and the results need further investigation to determine the possibility to detect the functional and pathological changes, as well as compensatory possibilities of microcirculation in normal and in pathology.

We studied the patients had the acute cerebrovascular events after the community acquired pneumonia evoked by new COVID-19 infection. The aim of our paper is improving the diagnosis and treatment of that condition. Materials and methods. We analyzed the stroke clinical features of 121 patient suffering from community acquired pneumonia induced by COVID-19 for the first time. Two groups were formed depending on the proved pulmonary damage. The main group included 69.4 % of patients (n=84) with diagnosis of new coronavirus disease plus stroke. Patients with ischemic and hemorrhage stroke in absence of SARS-CoV-2 signs were formed control group (30.6 %; n=37). We compared severity of the diseases and explored the biochemical characteristics in the both groups. Outcomes of severe cerebral and pulmonary injury were analyzed statistically. Results. Post-stroke patients with coronavirus disease showed predominantly the ischemic stroke (86.4 %) for unspecified (41.4 %) and cardioembolic (35.7%) pathogenetic subtypes (according to TOAST) with localization in the carotid basin (89.7 %). The hemorrhagic stroke more often was accompanied by parenchymal hemorrhage (54.5 %). The severity of the developed stroke according to the NIHSS scale is up to 13.16 (8.80) points with less severe brain damage Glasgow coma scale (14.0 (12.0 15.0). In the group of patients, widespread lung tissue damage was diagnosed in 82,2% of cases. The reliable increase of clinically relevant hypercoagulation signs was absent. Conclusions. Post-stroke patients with COVID-19 mainly have ischemic signs with unspecified and cardioembolic subtypes in absence of any sex and age features. The differences in disease severity are absent. The outcomes of diseases are mainly favorable. The high activity of inflammatory changes is clinically revealed.

The aim is to study the effect of endogenous opioid peptides on the contractile activity of lymphatic vessels in the white rat. Materials and methods. Under isometric conditions, the dynamics of spontaneous contractile activity of isolated annular segments of rat lymphatic vessels under the action of endogenous opioid peptides (beta-endorphin and endomorphin-1) was record; possible mechanisms of opiates action were studied. Results. The range of β-endorphin level 1×10^–11–1×10^–8 M resulted in a decrease of the minute productivity of the lymphatic vessels, by 22%, mainly due to a decreasing of single contractions frequency. In the presence of blockers of voltage-gated and ATP-sensitive potassium channels and blockers of eNOS, the inhibitory effect was not manifest. Endomorphin-1, used in the concentration range of 1×10^–10–1×10^–8 M, stimulated the contractile activity of the lymphatic vessels by an average of 15 %. The stimulatory effect was not manifest when using endomorphin-1 in the presence of a selective NK1 receptor antagonist. Conclusions. The inhibitory effect of β-endorphin is associated with the activation of voltage-dependent and ATP-sensitive potassium channels, endothelium-(NO)-dependent mechanisms. The action of endomorphin-1, stimulating lymphangionic motility, can be carry out through interaction with NK receptors.

Introduction. The relevance of the problem of high mortality in acute lung edema (ALE) is associated with the insufficient effectiveness of treatment methods for extreme rapidly occurring lung pathology. The goal is a comprehensive study of the role of lymph flow stimulation using a lymph-stimulating peptide in the pathogenesis of ALE under conditions of lung biomicroscopy. Materials and methods. Biomicroscopy of the lungs using an implanted chamber and mesentery of the rat small intestine, laser Doppler lung flowmetry, morphological and histological examination of the lungs. Registration of contractile activity of the wall, valves of the lymphatic microvessels of the mesentery by photometry and the rate of lymph flow; determination of the diameter of microvessels, solids and pulmonary coefficient in the lungs. photo and video registration of the lungs. Results. The direct peptidic lymphostimulant caused activation of lymphatic flow in the lymphatic microvessels of the mesentery and lungs in patients with ALE, followed by restoration of microcirculation in the lungs. The reduction and elimination of edema of the interstitial space in the lungs was associated with the restoration of the diameter of the lymphatic and venous microvessels. Prophylactic use of the peptide was accompanied by an increase in animal survival by 3 times. The use of the peptide after the ALE did not affect survival, however, it increased the life expectancy of rapidly dying animals during the first 10 min up to a day from 16 to 46 %. Conclusions. Activation of motility of the lymphatic microvessels and lymph flow in ALE with the help of a peptidic lymphostimulator, an agonist of the delta opiate receptors, helps to eliminate edema as a result of removing excess interstitial fluid through the lymphatic vessels of the lungs to the main venous collectors and then to the right atrium, than reduces the load on the left half of the heart with cardiogenic ALE. The restoration of microlymph- and microhemocirculation in the lungs contributed to the restoration of the structure of the lung tissue and a 3-fold increase in the survival and longevity of animals. Activation of the lymphatic system is an effective, but unused reserve of the body playing an important role in the pathogenesis of ALE.

Introduction. The lymphatic system maintains a steady state of organism and plays crucial role in a volume regulation of fluid surrounding the organs. The researching goal is to study the fluid redistribution process and to reveal adrenoceptive renal innervation of its lymphatic nodes in toxic hepatitis. Materials and methods. We studied the rat kidneys and their renal lymphatic nodes. The lymph flow of renal nodes and its adrenergic innervation were evaluated. Results. Rats with toxic hepatitis showed the decreasig fluorescence of adrenergic nerves and absence of the single neurons in kidney tissue and pelvis. Nerves in the renal parenchyma adjacent to the lymphatic nodes had a weak fluorescence. The average decreasing of lymph flow, volume of blood plasm and diuresis was 35, 21 and 60 %, correspondently. The disturbance of fluid redistribution, whole protein and electrolytes were observed. Conclusions. Toxic hepatitis leads to the destruction of adrenergic innervation in the tissues and blood vessels of the kidneys and renal lymph nodes, the disappearance of small terminals of nerves and part of varicose thickenings, the depots of catecholamines. This causes the diffusion of catecholamines into the surrounding tissues, suppressing the efferent signaling of nervous processes. The rats with hepatitis have had an impaired water-salt homeostasis resulted in a decreasing volume of plasma, circulating blood and lymph flow. The lymphatic system in hepatitis promotes the uptake of potassium and calcium ions released from the bloodstream, preventing them from being excreted in the urine.

Its given significance of lymphangion as a structural-functional unit in the new theory of structure and functions of the lymphatic system. The construction of lymphangion in pathogenesis of lymph edema is represented. Treatment and prophylaxis must be directed at all parts of the lymphatic system.

The review describes pathogenesis of the disease caused by the new SARS-CoV-2 virus. It infects the human cells by linking angiotensin-converting enzyme-2 (ACE2) and a number of other receptors. The virus imbalances the renin-angiotensin system, results to vasoconstriction and acts like pro-inflammatory agent. ACE2 is exposed on the alveolar epithelium cell surface. It is the main gates for virus entering and damaging of the respiratory system resulted in an acute respiratory distress syndrome. The injuring of the pulmonary vessel endothelium is the most important part of the COVID-19 pathogenesis. ACE2 of the endothelial and smooth muscle cell surface upon the SARS-CoV-2 infection facilitates the injury of cardiovascular system. The development of endotheliitis induced by «cytokine storm» leads to the main signs of the disease and the multiple disorder of the microcirculation. The investigation of that condition has a prognostic value and determines the treatment especially in critically ill patients. Systemic endothelial dysfunction upon the COVID-19 largely triggers the hemostasis disorders. High activity of platelets adhesion and aggregation, blood coagulation in died COVID-19 patients, disorder of fibrinolysis system functional activity could be induced by the endothelium activation. The unchanged anticoagulation blood activity in the COVID-19 patients distinguishes them from the patients with disseminated intravascular coagulation. Monitoring of the hemostasis system in COVID-19 is important for the disease severity assess and its prognosis, for justin-time correction of detected deviations.