SCIATIC NERVE REGENERATION AFTER AUTOGRAFTING AND APPLICATION OF THE BONE MARROW ASPIRATE CONCENTRATION.

The work aims at studying the effect of the autologous bone marrow aspirate concentrate on regeneration of the sciatic nerve and atrophy of m. tibialis cranialis. We have simulated autografting of the sciatic nerve in rabbits with application of bone marrow aspirate concentrate around the graft area. We obtained autologous aspirate (2mL) from the proximal part of the femur, added dextrosecitrate (1:8), centrifuged it, and added 0.1 of bovine thrombine to 1.0 mL of supraerythrocytic fraction to obtain gel. On days 30 and 90 we assessed the rate of the sciatic nervere generation and morphological changes of the m.tibialis cranialis as well as the content of products of oxidative modification of lipids and proteins (TBA-active products, diene conjugates and carbonyl groups, respectively) and activity of antioxidant enzymatic system (catalase, glutathion peroxidase, glutathione reductase) in this muscle. Evaluation of the nerve fibers regeneration through the sciatic nerve graft 1 cm long showed that 16.0% of them had regenerated into the graft by day 30 and 60.3% by day 90, with 34.7% having regenerated into the distal stump. Application of bone marrow aspirate concentrate had significantly increased regeneration by day 30, amounting to 31.9% in the graft and up to 8.7% in the distal stump and up to 68.0% and 60.1% by day 90 respectively. Prolonged nerve regeneration resulted in progressive muscle atrophy, with decrease of muscular fibers content up to 68.2% and 27.8%. In the group with aspirate concentrate hypothrophy was delayed (% of muscle fibers being 82.8% and57.2%). The content of peroxidation products has dramatically increased by day 30 and has decreased by day 90 with activation of glutathione peroxidase and glutathione reductase enzymes (with catalase activity being significantly high in all the terms).We have also observed decreased oxidative modification of lipids and proteins in the aspirate concentrate group, with additional increase of glutathione peroxidase activity demonstrating the supportive effect of the aspirate cells.

[A STUDY OF IMPACT OF MERCURY CHLORIDE ON MYOCARDIUM IN EXPERIMENT].

The article is devoted to the study of the myocardium structural reorganization features under the action of 0,01 LD50 of mercury chloride (II) rats when comparing chronic (30 injections) and subchronic (10 injections) exposures. Structural-metabolic reorganization of the myocardium was studied using histological, histochemical and electron microscopic methods. Computer morphometric analysis with subsequent statistical processing was applied. It was established that the main mechanisms of cardiotoxic effect of mercuric chloride are: hypoxia (due to damage to micro vessels; disorder of myogenic regulation at the expense of damage intercalated discs) and the appearance of cell detrits and abnormal proteins as a result of the destruction of cardiomyocytes. Sensitive to the toxic effects of chloride mercuric in low doses are myofibrils, sarcoplasmic network and the energy apparatus of cardiomyocytes - the mitochondria. It was found that chronic exposure to low doses of mercuric chloride causes non-specific qualitative and quantitative changes in all structural components of the heart, damage to the tissue barrier is ongoing and dynamic and resorptive insufficiency hemomicrocirculatory bed of the heart that leads to chronic swelling that causes the development of diffuse fibrosis and enhances cardiac decompensation activities.