Platelets are unique blood elements that, in addition to blood coagulation, modulate the processes of fibrinolysis, inflammation, physiological regeneration, repair, angiogenesis, bone tissue formation, formation of the mother-placenta-fetus system, etc. Of particular interest is the phenomenon of spontaneous platelet aggregation in vivo under various physiological and pathological conditions, which is associated with expanded capabilities for assessing the risks of thrombotic events. A separate aspect of this problem is associated with the study of the mechanisms and biological role of reversible platelet aggregation. To date, the significance of this phenomenon under normal and pathological conditions remains not entirely clear. This review is devoted to the phenomenon of spontaneous reversible platelet aggregation, the modern understanding of its mechanisms, approaches to its diagnosis and its association with various pathological conditions.

Cardiorenal syndrome is a complex condition that belongs to the category of acute or chronic kidney pathology that causes cardiovascular disease, and, conversely, acute or chronic heart disease that provokes kidney dysfunction. The relationship between the pathology of the cardiovascular system and the kidneys is due to the commonality of risk factors for the pathology of both systems. In recent years, the link between regulators of mineral metabolism - vitamin D, parathyroid hormone, endocrine growth factors of fibroblasts 19,21,23, Klotho protein with the development of heart failure, atrial fibrillation, left ventricular hypertrophy, as well as the progression of chronic kidney disease has been proven. The increased levels of fibroblast growth factor-23 and a decrease in the soluble fraction of Klotho protein in plasma are recognized as early markers of chronic kidney disease and cardiovascular disease. Further study of the influence of mineral exchange regulators on cardiorenal syndrome creates a new direction in the treatment of cardiovascular diseases and chronic kidney disease.

Introduction. Skin complications in the form of bedsores, ruptures in places of hardware, failure of skin sutures occur in children with congenital scoliosis (CS) at various stages of treatment of the spine deformities. At the same time, microcirculatory blood flow of the skin is one of the factors determining reparative regeneration. However, there are no studies in the literature devoted to the analysis of the state of blood circulation in the skin of the back in children with CS. Aim. To determine the distinctive microcirculatory features in different parts of the back in children with congenital scoliosis. Materials and Methods. Two groups of children were examined: group 1 – 40 patients with CS; group 2 – 49 healthy subjects. Skin blood flow was assessed using laser Doppler flowmetry. In children with congenital scoliosis, histological examination of skin biopsy material taken in the area of the deformity apex during surgical correction of the spinal deformity was carried out. Results. In children with CS, there was a significant decrease in skin blood flow in the middle and lower parts of the back along the paravertebral lines compared to the indicators of healthy children by 0.6–01.06 ml/min×100 g (15–28 %, p=0.0000). Blood flow values in these parts were inversely correlated with age (r from –0.47 to –0.73, p <0.001) and with the magnitude of the deformity angle (r from –0.4 to –0.68, p<0.05). The minimum values were recorded on the concave side of the deformity in the middle part of the back in the projection of the paravertebral lines (2.74±0.71 ml/min×100 g). Histological investigations of the skin in this area revealed the presence of destructive changes in the vessels of the dermis: fibrosis, sclerosis, the formation of perivascular inflammatory infiltrates and signs of vasculitis, which worsened with increasing the deformity angle. Conclusion. In children with CS, blood flow of the skin integument of the back is significantly reduced in the middle and lower parts. The lowest level of perfusion is found at the apex of the deformity on the concave side along the paravertebral line. In this area, destructive changes in the vessels of the dermis are revealed, which are aggravated with the increase in the angle of the spine deformity, that leads to a decrease in their numerical density and ischemia of the skin integument.

The aim of the study was to assess the relationship between the levels of Anti-ACTC1, Anti-MYH7B and Anti-cTnI autoantibodies in blood serum with the electrocardiogram results in athletes undergoing intense physical exercise in order to predict adverse cardiovascular events. Materials and Methods. This work included a medical examination of two groups of men aged 18–22 years (n=15) and 18–25 years (n=20) with different amounts of total motor activity. The study was conducted in accordance with the recommendations for a stage medical examination of cyclists, which includes the determination of the anti-ACTC1, anti-MYH7B, anti-cTnI levels in blood serum. Results. Intense physical exertion and psychoemotional stress activate the immune response and increase the severity of serum antibodies increases. In particular, there is a significant increase in antibody expression: Anti-ACTC1 by 18.0%, Anti-MYH7B by 20.1%, Anti-cTnI by 40.9% (p<0.01). In addition to the expression of antibodies to contractile apparatus proteins, there are electrocardiographic abnormalities (p>0.05): violation of the processes of cardiac repolarization and ventricular conduction, ST segment elevation, the QRS complex elongation by 17.0%, the QT interval shortening by 27.5% and corrected QT (QTc) by 30.3%, as well as the PQ interval prolongation by 15.0%. Conclusion. Considering the increase in the autoantibody levels during physical exertion, this can be considered as an early indicator of myocytes and cardiomyocytes damage during physical overload.

Introduction. Today, a number of stents are widely used in the world, differing in material, design, drug composition and the content of the polymer coating. The aim of our study is to investigate the processes of neoendothelialization according to optical coherence tomography data in patients with stable coronary heart disease after implantation of various stent platforms. Materials and Methods. This study is a retrospective data analysis of stenting results in patients with stable ischemic heart disease. A total of 69 patients were included in the study. Patients were divided into 3 groups by the type of stent implanted: group 1 everolimus-eluting permanent polymer stent (EES-PP) (n=25), group 2 everolimus-eluting bioabsorbable polymer stent (EES-BP) (n=25) and group 3 sirolimus-eluting bioabsorbable polymer stent (SES-BP) (n=19). The primary endpoint of the study was the Neointimal Healing Score (NHS) 3 months after stent implantation. The secondary endpoint included the percentage of struts covered 3 months after stenting. Results. The percentage of covered strata in the groups did not have a statistically significant difference between the groups and was about 84.2%. Since the length of the implanted stents was slightly higher in the SES-BP group, the difference in the number of strata studied was higher in group 3: 331 versus 175 in group 2 and 175 in group 1 (1–2: p=0.969; 2–3: p<0.001; 1–3: p<0.001). The primary endpoint of the study was significantly lower in the SES-BP group (18±14.97 vs 32.5±20.3 in the EES-BP group and 25.6±12.3 in the EES-PP group), but the NHS in the EES-BP and EES-PP groups was not statistically different. Conclusion. The sirolimus-eluting bioabsorbable polymer (SESBP) stent has a better neointimal healing rate during the first three months compared to the everolimus-eluting bioabsorbable (EES-BP) polymer stent and the permanent polymer everolimus-eluting (EES-PP) stent in patients with stable ischemic heart disease. The percentage of covered strata in the groups does not differ significantly. Further prospective randomized studies with larger samples are needed to confirm the findings.

Nowadays, the use of tobacco through hookah smoking has become popular, especially among young people. Therefore, the aim of the study was to investigate the effect of hookah smoking on the parameters of vascular wall stiffness determined by volumetric sphygmography in young people (19–25 years old) without cardiovascular pathology. Materials and Methods. The main group included 60 students who have been using hookah for more than 1 year, at least 2 times a week. The control group included 57 students who did not use any type of nicotine-containing substances. The groups were comparable in age, body mass index, blood pressure and heart rate. In both groups, vascular wall stiffness was assessed by volumetric sphygmography. Results. Although the average value of the CAVI index was within the normal range in 20% (n=12) of the students of the main group, this index exceeded the age criteria and amounted to 7.5±0.3 m/s. Correlation analysis showed the relationship between the CAVI index and hookah smoking experience (r=0.46, p<0.01). A follow-up study was conducted 3 years later on 29.9% (n=38) of the students. Among them, 42.1% (n=16) quit hookah smoking, and 57.9% (n=22) continued to use hookah. The PWV and SAVI indicators significantly returned to normal in students who stopped smoking hookah, in contrast to the indicators of the students who continued to smoke hookah. Conclusion. Hookah smoking increases vascular wall stiffness in young people (19–25 years old) without cardiovascular pathology.

Introduction. The deep femoral artery is one of the main arteries in the blood supply to the lower limb, becoming an indispensable adjunct to atherosclerotic lesions of the superficial femoral artery and tibial arteries. For many years, the issue of its revascularization has occupied the minds of most vascular surgeons. However, in the minds of many, only the terms «good» or «bad» were used to evaluate its characteristics. Aim. To study the dependence of the severity of lower extremity arterial insufficiency on the type of deep femoral artery structure and the state of the lower limb arterial channel in patients with atherosclerotic limb ischemia. Materials and Methods. The study included 40 women and 80 men, aged from 53 to 84 years (66.7±7.4). The inclusion criteria were the presence of a patent aortoiliac segment, patent deep femoral artery, and occlusion of the femoropopliteal segment. Patients were divided into 2 groups according to the anatomical structure of the deep femoral artery: 1) trunk type; 2) branched type. In order to adequately assess the influence of anatomical parameters on the degree of ischemia, the following characteristics were studied: number of perforating branches; length of the deep femoral artery; number of traversable arterial trunks of the leg. Results. When correlating the types of PFA structure with the degree of limb ischemia, no significant differences were found in the studied groups – p=0.096. However, it should be noted that, numerically, with ischemic damage of degrees III and IV, the dispersed type of PFA structure was found in 4 (22.3%) and 14 (30.1%), respectively. There was also no significant relationship between the degree of limb ischemia and the number of perforating branches of the PFA (p=0.278). Thus, 2^nd order perforating branches were found in 56 (57.1%) patients with the main type of GBA structure and 3^rd order branches – in 32 (32.6%). In contrast to the above results, the analysis of the extent of the PFA demonstrated a significant dependence of the studied indicators. With the extension of the main trunk of the deep femoral artery to the level of the middle-lower third of the thigh, grade 2b ischemia was observed in most cases – 40 (71.4%), while among the patients in other ischemia groups, this indicator was observed only in 8 patients (p=0.001). Conclusion. The extent of the deep femoral artery and preservation of the tibial arterial bed are significant factors influencing the degree of arterial insufficiency.

The aim was to study the role of transcutaneous oximetry of buttock region in the diagnosis of proximal claudication. Materials and Methods. The retrospective study included 19 patients with atherosclerosis of the lower extremity arteries. The minimum absolute values of transcutaneous oxygen pressure recorded in the gluteal regions at rest, sitting and standing, during and after treadmill walking, as well as their ratios depending on the presence or absence of clinical signs of proximal claudication were subjected to comparative analysis. The predictive value of transcutaneous oxygen pressure in the diagnosis of occlusive-stenotic disease of the common and internal iliac arteries was analyzed. Results. There were no statistically significant differences in the absolute value of the transcutaneous oxygen pressure between the groups; statistically significant differences in their ratios depending on the measurement period were established. When the level of the ratio of transcutaneous oxygen pressure in the recovery period after the treadmill test to the same measured initially in the sitting position is less than or equal to 80%, the sensitivity and specificity in the diagnosis of the occlusive arterial disease are 71% and 86%, respectively. Conclusion. The transcutaneous oximetry in the buttock regions during the exercise test is a sensitive and specific indicator of the aortic, common or internal iliac artery occlusive disease in patients with suspected proximal claudication.

Introduction. Ischemic stroke is one of the leading cause of disability and death. One of the promising therapeutic methods is cell therapy. The choice of an appropriate experimental stroke model is of great importance for studying the restorative effect of cell therapy in the laboratory. An experimental model using endothelin-1 allows to induce damage in the cortical and subcortical brain structures, while being relatively easy to perform and less traumatic. Aim. To assess the effectiveness of an ischemic stroke model reproduced using endothelin-1 to analyze the results of general cellular therapy on recovery processes. Materials and Methods. Male Wistar-Kyoto rats were divided into groups: sham operation (n=4), ischemia control (n=4), cell control (n=9), cell therapy (n=8). Damage was assessed by using morphometry and immunohistochemistry with antibodies against NeuN, GFAP, nestin, and vimentin. Results. It has been established that this model causes ischemic damage in the area close to the injection site with characteristic cellular reactions. Assessing the size of the damage showed a large within-group variability, which did not allow us to confirm the expected effect of the cell therapy. Conclusion. The endothelin model of cerebral ischemia is suitable for studying the cellular reactions that develop after ischemic stroke, but the significant variability in the volume of damage does not allow it to be recommended for quantitative assessment of the effects of cell therapy.

Aim. To assess systemic vasomotor activity of blood vessels of Wistar rats with premorbid chronic cardiomyopathy infected with influenza A(H1N1)pdm09 virus. Materials and Methods. The study was performed on 30 mature male Wistar rats. The animals were divided into three groups: 1) chCMP – animals with chronic cardiomyopathy; 2) IAV – healthy animals infected with influenza A/St Petersburg/48/16 (H1N1)pdm09 virus; 3) chCMP + IAV – animals with premorbid cardiomyopathy infected with the studied virus. Chronic cardiomyopathy was modeled by intraperitoneal administration of doxorubicin. At 1 and 7 days post-infection (dpi), rats were anesthetized followed by necropsy with extraction of the mesentery and isolation of the third-order mesenteric arteries. Vasomotor activity of mesenteric blood vessels was assessed by wire myography. Results. The viral infectious titer in pulmonary tissues of rats in the chCMP + AIV group at 1 dpi was 6.2 lg EID50/ml, while it was lower in the AIV group – 5.6 lg EID50/ml (p < 0.05). After 7 dpi, no infectious titer was detected in pulmonary tissues. The sensitivity of mesenteric blood vessels to the vasoconstrictor in the chCMP + IAV group after 1 dpi was increased by 7% compared to the chCMP group (p < 0.05). Also after 7 dpi, a tendency toward attenuation in integral response (based on area under the curve) of mesenteric arteries in the chCMP + AIV group to vasoconstrictor and vasodilator was observed compared with the chCMP group. Conclusion. Influenza A(H1N1)pdm09 virus aggravates systemic alterations in vasomotor activity of blood vessels in rats with chronic cardiomyopathy, which is characterized by a decrease in the integral response of mesenteric microvessels to vasoconstrictor and vasodilator after 7 dpi. 

Introduction. The development of effective treatment of skin wounds is the one of the current challenges. Synthetic wound dressings based on polylactide, capable of targeted delivery of biologically active substances, provide new solutions to the problem of stimulating regeneration. Tannic acid seems to be a promising substance as a component of wound dressings due to its antiinflammatory and antioxidant effects. The aim of the study was to assess the changes in the serum concentrations of markers of angiogenesis, endothelial cell alteration and activation under the influence of microchamber polylactide wound dressings loaded with tannic acid during the healing of an experimental full-thickness skin defect in white rats. Materials and Methods. The experiment was carried out on 63 white male rats, divided into four groups: intact animals (n=9), comparison group (n=18), experimental groups No. 1, 2 (n=18 each). A 10×10 mm acute excisional skin wound model was surgically created in animals of the comparative and experimental groups. Animals in the experimental group № 1 received a polylactide microchamber wound dressing without active components on the formed skin defect. The rats of experimental group № 2 received a similar dressing with its microchambers loaded with tannic acid. The concentrations of vascular endothelial growth factor (VEGF), syndecan-1, and sE-selectin in the blood were assessed. Results. It was found that the healing of a full-thickness skin defect in rats is accompanied by alteration and activation of the endothelium, characterized by an increase in serum concentrations of syndecan-1 in 4.4 times and sE-selectin in 2.2 times. There is also an activation of angiogenesis with increase in VEGF concentration 1.7 times on the 7^th day and 6.5 times on the 14^th day of the experiment. Dressings with tannic acid cause a decrease in the alteration of the endothelial glycocalyx and inflammatory activation of endothelial cells, which is manifested by a decrease in serum concentrations of VEGF and syndecan-1 by 2 times and sE-selectin by 1.7 times on the 7^th day of the experiment compared to the analogue without active components and complete normalization of the serum concentration of the angiogenesis stimulator VEGF by the 14^th day of the experiment. Conclusion. Polylactide wound dressings with micro-chambers filled with tannic acid have a significant effect on the course of the wound process in rats with a full-thickness skin defect.

Introduction. The lymphatic system plays a key role in spreading pathogens, including those causing intraabdominal infections. An urgent task of pharmacology is to create methods for the targeted delivery of antibiotics to lymphatic vessels and intestinal tissues. One approach is to use agents acting as endolymphatic conductors to achieve a high drug concentration in the lymphatic system. Aim. To evaluate the effect of various drugs on the concentration of cefotaxime, a third-generation antibiotic, in blood and intestinal tissues, as well as on lymphatic drainage in experiments on mice. Materials and methods. We investigated the effect of hyaluronidase (HLRD), bovgialuronidase azoximer (BovGLRD+Az), terrilitin (TRL), papaya milky juice (PMJ ), sodium heparin (HepS ), aprotinin (APRT), azoximer bromide (AzBrom), furosemide (FRSD) and sodium deoxyribonucleate (DRN) on the removal time of lymphotropic dye from mouse mesentery and the cefotaxime concentration in blood plasma and intestinal tissues by high-performance liquid chromatography. Results. HLRD reduced the time of dye removal from the mesentery by 26.2%, BovGLRD+Az – by 33.5%, TRL – by 36%, PMS  – by 23.1%, HepS  – by 30.1%, APRT – by 34.6%. The differences in lymphostimulating activity between these drugs were not statistically significant. AzBrom and FRSD increased the dye removal time by 8.3% and 6%, respectively; the DRN had no effect. HLRD, BovGLRD, TRL, PMJ, HepS and APRT increased the CF concentration in blood and intestinal tissues 1.5 and 24 hours after injection, in contrast to the single injection of antibiotic. AzBrom increased the CF concentration only after 1.5 hours. FRSD increased the antibiotic concentration in intestinal tissues but not in blood plasma. The DRN did not affect the studied indicators. Conclusion. Lymphostimulating drugs HLRD, BovGLRD, TRL, PMJ, HepS and APRT effectively direct the antibiotic to the lymphatic system and can be used for lymphotropic therapy.