Investigation of blood flow parameters in the microvasculature in adolescents football teams during the training process

The limiting role of the cardiovascular system when performing sports loads is associated not only with central hemodynamics, but peripheral mechanisms, regulating blood flow. One of the indicators playing a significant role is a velocity of capillary blood flow. Using the method of high-frequency ultrasound dopplerography, the study of blood flow characteristics in a microvasculature at rest and after exercise session was conducted in 53 adolescents at the age of 9-15 years with different sport experience. During these studies it was found that background blood flow velocity values in the arteriolar and capillary bed (p≤0.05) are higher, and vascular tone is lower in adolescents of 14-15 years and adolescents having a longer sport experience, compared with adolescents of 9-13 years. Blood flow indicators in a microvasculature of the older age group are closer to the values recorded in adults. Various mechanisms aimed at maintenance of muscle oxygenation during exercise, are revealed after exercise session. It is confirmed visually (on the dopplerogram) and quantitatively that mechanisms increasing blood flow to muscles are activated at less-trained adolescents (9-13 years old) during exercise. More efficient mechanisms are observed at the older age group: redistribution of blood flow and increase in number of functioning capillaries.

A Review of Platelet Derived Growth Factor Playing Pivotal Role in Bone Regeneration

This article is focused on the literature review and study of recent advances in the field of bone grafting, which involves platelet-derived growth factor (PDGF) as one of the facilitating factors in bone regeneration. This article includes a description of the mechanism of PDGF for use in surgeries where bone grafting is required, which promotes future application of PDGF for faster bone regeneration or inhibition of bone growth if required as in osteosarcoma. The important specific activities of PDGF include mitogenesis (increase in the cell populations of healing cells), angiogenesis (endothelial mitoses into functioning capillaries), and macrophage activation (debridement of the wound site and a second phase source of growth factors for continued repair and bone regeneration). Thus PDGF can be utilized in wound with bone defect to conceal the wound with repair of bony defect.

The condition of the microcirculatory channel of the nail bed of the upper extremities and changes of central venous pressure in patients with the second stage of essential hypertension depending on the structure of the diurnal rhythm of arterial pressure

The peculiarities of changes of the microcirculation of the nail-bed and central venous pressure (CVP) have been presented in the poper in patients the with 2nd stage of essential hypertension depending on different variants of the circadian rhythm of arterial pressure. An inverse interdependence has been established between the level and a decrease of the specific gravity of the functioning capillaries in the patients with a low (non-dipper) and negative (night-picker) diurnal index of arterial pressure that con be used as diagnostic criteria of a high risk of possible complications of essential hypertension.