Reactivity of the Blood Microcirculation System in Primary School Children to the Temperature Factor

The purpose of the study was to investigate the adaptive capacity of the blood microcirculation system in children of primary school age for a functional test with heating. The article deals with the study of the blood microcirculation system in primary school children by laser Doppler flowmetry and the study of the reserve capacity of tissue blood flow in children on a test with increasing temperature factor. Materials and methods. The research was conducted on the basis of the laboratory of physiological research of the Department of Anatomy and Physiology of People and Animals of Bohdan Khmelnytsky Melitopol State Pedagogical University. The surveyed contingent consisted of 80 practically healthy children aged 6 to 9 years old, secondary school students in Melitopol. Based on a comprehensive morphofunctional study, we obtained data on individual-typological features of blood microcirculation in primary school children and the reserve capacity of tissue blood flow using functional tests. It is established that the adaptive features of the blood microcirculation system in boys and girls of early school age are due to different levels of local and central mechanisms of microvessel regulation. Results and discussion. The results obtained during the thermal test indicate different levels of reactivity of the body to increasing the temperature factor and the neurogenic vasoconstrictor effects of the sympathetic nervous system on the vessels of the arteriolar part of the microcirculatory tract. The reaction to the thermal test directly depends on the individual-typological features of blood microcirculation. Conclusion. At a ratio of reaction to thermal influence in children with various types of microcirculation, the maximum increase in tissue perfusion was observed in children with type III of laser Doppler flowgram. This level of microvascular reactivity, as well as the relatively rapid recovery of blood flow after thermal hyperemia is explained by the fact that children with hyperemic type of microcirculation have increased microvascular tone due to neurogenic effects of the sympathetic chain of tissue blood flow regulation. Children with the hypoemic type of microcirculation, on the other hand, have a somewhat reduced sympathetic tone relative to the normoemic type, as a result of which the reserve of capillary blood flow is reduced and the time of blood flow recovery after thermal exposure is prolonged

Influence of millimeter electromagnetic waves on the functional capabilities of the lower limb muscles in athletes - volleyball players

The authors, when observing 22 athletes - volleyball players of different volleyball specialization, assessed the effect of millimeter electromagnetic waves (EMW) on the functional state of the muscular system of the lower extremities. The electromagnetic effect was carried out using the "Complex SP 80" apparatus (frequencies 3900 - 4120 kHz were used). Electrodes were applied to the muscles of the thigh and lower leg, sinusoidal discharges were applied for 10 seconds during the strength training period. The results of observations showed that under the influence of EME, the height of the jump increases by 7%, due to the increase in the energy of the jump and its intensity. The release of the activity of the knee joint is also noted. The authors believe that under the influence of EME, the transmission of regulatory impulses in neuromuscular contact improves, which contributes to the synchronization and strength of contractions of the muscle fiber bundles. Also, under the influence of EMW, blood microcirculation in the muscle improves.

Leukocyte adhesive function in Intensive Care patients with non-infectious and infectious systemic inflammation

Background: The lack of rapid and accurate diagnostic tools to distinguish infectious (known as sepsis) and non-infectious causes of inflammation in patients with systemic inflammation remains a significantly unmet clinic need, particularly in the intensive care unit (ICU). As a hallmark of inflammation, circulating leukocytes must be activated and undergo a cascade of interactions with blood vessel endothelium before transmigrating into surrounding tissues, a process called leukocyte recruitment. Given the divergent disease aetiologies, it was hypothesised that the ability of circulating leukocytes to interact with endothelial cells and cause inflammation may differ when responding to infectious and non-infectious inflammatory stimuli, providing potential markers to differentiate these two diseases. Methods: In the present study, a flow-based blood testing platform, named leukocyte adhesive function assay (LAFA), was used to mimic blood microcirculation in vitro so that the patient leukocyte ability to interact with multiple endothelial molecules, including P+E selectins, VCAM-1 and IL-8, can be studied. The leukocyte adhesive functions of multiple leukocyte subsets were quantitatively assessed using a range of cell kinetic parameters, including cell speed, straightness, dwell time etc.Results: When analysed on P+E selectin substrate, a significantly lower value of cell straightness was observed in septic CD4 cells than non-infectious cells (0.78±0.04 vs 0.92±0.01, p < 0.01), suggesting a difference in CD4 cells ability to adhere to selectins in infectious and non-infectious patients. Additionally, an impaired ability to respond to IL-8 was observed in septic neutrophils compared to non-infectious cells, evidenced by a significantly reduced cell dwell time (91.7±14.0 vs 150.6±19.0 seconds, p < 0.05).Conclusions: Thus, our study promisingly showed the ability of LAFA to detect different adhesive function between leukocytes from ICU patients with infectious and non-infectious systemic inflammation. LAFA generated a number of novel markers that might distinguish infectious inflammation from non-infectious causes that warrant further study and novel opportunities for the rapid and accurate diagnosis of sepsis.

Combined Correction of Experimental Critical Ischemia of the Lower Extremities in a Rat Model

The purpose of our research was to study the effectiveness of correcting experimental critical ischemia (CI) of the lower extremities with a combination of udenafil, simvastatin, and autologous bone marrow mononuclear cells (ABMMC). Methods and Results: The experiments were carried out on 24-month-old Wistar rats, weighing 220–250g. The animals were randomized by sex and weight. Groups were formed according to the manipulations carried out during the operations. The animals were divided into 7 groups, each with 20 animals: Group 1 included intact animals; Group 2 - falsely operated animals; Group 3 (control group) - animals with simulated CI without treatment; Group 4- animals with CI and monotherapy with udenafil (daily oral administration of 8.6mg/kg for 28 days); Group 5 - animals with CI and simvastatin monotherapy (daily oral administration of 1.71mg/kg for 28 days); Group 6 - animals with CI and monotherapy with ABMMC (parenterally, once on Day 7 after modeling CI, 50μl at 4 points and, paravasally, above the inguinal ligament in the area where the lateral artery leaves the artery enveloping the femur from the internal iliac artery; in the area of the superficial artery that bends around the iliac bone under the inguinal ligament; into the area of origin of the muscular branch of the femoral artery r. muscularis, the place of attachment of the comb and long adductor muscles of the thigh; in the upper third of the gastrocnemius muscle]); Group 7 - animals with CI and combination therapy (udenafil and simvastatin drugs were administered intragastrically 0.86 mg/kg, once a day, for 7 days) and one-time parenteral administration of ABMMC, according to the same scheme as in Group 6. On Days 21 and 28 of the experiment, the level of blood microcirculation was determined in the muscles of the rat leg; for this, laser Doppler flowmetry was used. For further morphometric assessment of the leg muscles, they were removed. Preparations for morphometric analysis were prepared according to the standard technique with Van Gieson staining, as well as H&E. Our study demonstrated the effectiveness of combination therapy with udenafil, simvastatin, and ABMMC to correct critical lower limb ischemia in rats. The severity of morphological changes on the background of this combination was minimal, compared to the findings of other study groups, and the level of blood microcirculation in the ischemic zone on Day 28 was, significantly, 1.9 times higher than in animals of the control group. The results obtained allow us to recommend the use of the investigated combination (udenafil+simvastatin+ABMMC) for the treatment of patients with critical limb ischemia, both in outpatient and inpatient practice.

The study and analysis of the prognosis criteria for a safe local anesthesia in patients with arterial hypertension

Relevance. To develop the algorithm for a safe and effective local anesthesia in dental outpatients with arterial hypertension.Materials and methods. The study was conducted in the laboratory of functional and clinical studies of Moscow State University of Medicine and Dentistry. Electric pulp testing (µA) was performed and pulp microcirculation (PU) was assessed in the intact teeth of patients with hypertension before and 5, 10, 15, 30 and 60 minutes after the administration of local anesthesia. We used 4% articaine solutions without a vasoconstrictor and with its minimal concentration 1:200 000 and 1:400 000, and 3% mepivacaine solution. The safety of the administered local anesthetic was assessed by the continuous hemodynamic monitoring.Results. 4% articaine solution without epinephrine had a shallow anesthetic effect in the maxilla and anterior mandible. 1:400 000 and 1:200 000 vasoconstrictor concentrations in 4% articaine solution increase the depth and duration of the anesthesia from 20 to 30 minutes respectively. Changes in the pulp sensibility but not in blood microcirculation were demonstrated by the functional parameters of the intact dental pulp in patients with hypertension after the administration of 3% mepivacaine solution at the mandibular foramen. The continuous hemodynamic monitoring data showed no changes in arterial blood pressure, heart rate, oxygen saturation on administration of either of the studied local anesthetic solutions or techniques.Conclusion. The analysis of the prognosis criteria for a safe local anesthesia allowed us to ground the choice of anesthetic in dental outpatients with arterial hypertension.

Age peculiarities of the cardiovascular system and blood microcirculation in students under the influence of dosed physical training

We investigated the adaptive capabilities of the cardiovascular system and blood microcirculation in 18–21-year-old students under the influence of dosed physical training. It was shown that there are significant age-related differences in the indicators of the cardiovascular system function at rest. By the 21-th year the majority of the studied parameters have reached the level characteristic of adult young men. After dosed physical training the indices of the cardiovascular system function increased to a greater or lesser extent, and the greatest increase was observed in 21-year-old students. In younger age groups the changes were less effective, which characterizes the adaptive capabilities of the cardiovascular system depending on age. A marker indicator of the blood microcirculation system functioning — a microcirculation parameter that determines the direction of the microcirculation response to a dosed physical training — has been identified. It was found that among students of the 1st subgroup (low level of the microcirculation parameter) after physical activity it increased, and among students of the 2nd subgroup (high level of the microcirculation parameter) it mainly decreased, which characterizes the inclusion of various regulatory mechanisms in the blood microcirculation system. A decrease in the index of microcirculation efficiency under the influence of physical training was shown (the most significant in younger students). Such features can be explained by the lack of development of compensatory reactions in the microcirculation system.

Mathematical Models for Some Aspects of Blood Microcirculation

Blood rheology is a challenging subject owing to the fact that blood is a mixture of a fluid (plasma) and of cells, among which red blood cells make about 50% of the total volume. It is precisely this circumstance that originates the peculiar behavior of blood flow in small vessels (i.e., roughly speaking, vessel with a diameter less than half a millimeter). In this class we find arteriolas, venules, and capillaries. The phenomena taking place in microcirculation are very important in supporting life. Everybody knows the importance of blood filtration in kidneys, but other phenomena, of not less importance, are known only to a small class of physicians. Overviewing such subjects reveals the fascinating complexity of microcirculation.

Vascular Disaggregated Platelet Control in Newborn Piglets

The balance of platelet and vascular functions clearly determines the functioning of primary hemostasis in the piglet’s body. This is of particular physiological importance at the beginning of piglet ontogenesis. The degree of functional readiness of platelets and blood vessels in piglets during the neonatal period determines the state of blood microcirculation in tissues and the activity of many functional mechanisms at this stage of development. The activity of the disaggregation properties of blood vessels, which significantly determines the intensity of anabolism and, ultimately, the productivity of animals, is particularly important at this age. This study examined 31 healthy newborn piglets. A decrease in the amount of peroxidation products was found in the blood of all animals due to an increase in the antioxidant potential of their plasma, which created conditions in newborn piglets for weak alteration of the vascular endothelium and its optimal synthetic activity. This led to an increase in the vascular control over the platelet aggregation activity, maintaining the optimal blood flow in microvessels from the beginning of individual development. Keywords: piglets, neonatal phase, blood vessels, platelets, aggregation, lipid peroxidation