Role of matrix metalloproteinase 9 and its tissue inhibitor 1 in development and prognosis of diabetic retinopathy.

The article presents the results of investigation of violations in the proteolysis system in patients with type 2 diabetes and diabetic retinopathy (DR). We studied the levels of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinase-I (TIMP-1) in the blood and in the intraocularfluid ofpatients with type 2 diabetes depending upon the stage of DR. We have established that the level of MMP-9 and TIMP- in the blood and in the intraocular fluid increased in patients with type 2 diabetes without signs of DR and with any stage of DR compared to the levels of these parameters in patients without diabetes. Increasing the levels of MMP-9 and TIMP-J took place with increasing of DR severity and reached its maximum levels at the proliferative stage of DR. It was found that the levels of MMP-9 in the intraocular fluid and type 2 diabetes duration affected theprobability of developing diabetic macular edema. At the level of MMP-9 105 ng/ml and 2 diabetes duration 10 years, the probability of developing macular edema was 100%. As a result of the construction ofpredictive models it was found that the level of MMP-9 in the intraocular fluid, stage of DR at the beginning of observation and type 2 diabetes duration had influence on the probability of the development ofproliferative DR over 4 years offollow-up. If the level of MMP-9 100 ng/ml, type 2 diabetes duration 10 years and absence of DR at the beginning of observation were observed the probability of developing proliferative DR would compose 85.9%.

[Correlation between the thickness of air-blood barrier of the lung and main indices of respiration during changes in oxygen concentration]. / Vzaiemozv'iazok tovshchyny aerohematychnoho bar'iera lehen' ta osnovnykh pokaznykiv dykhannia pry zmini kontsentratsiï kysniu.

In experiments on adult white laboratory rats the correlation among external respiration, gas exchange and blood O2 transport under breathing by air and gas mixtures with 40%, 14.5%, 11% and 7% O2 in N2 was investigated. It was demonstrated the narrow structural-functional interrelation in oxygen transport system. The thickness of air-blood barrier (ABB) correlates not only with the external respiration and diffusion capacity of lung, but with parameters, which are not directly connected with the state of lung tissue, such as oxygen content in venous blood, VaO2/VO2 and even with circulation volume. The existence of narrow correlation of ABB thickness and the most of investigated parameters permits to prognosticate the availability of structural disturbances in the presence of external respiration, gas exchange and blood O2 transport changes.

[Human heart and endothelium functional activity depending on age and sex]. / Rabota sertsia ta funktsional'na aktyvnist' endoteliiu zalezhno vid viku i stati liudyny.

The complex study ofcardio-hemodynamics and functional activity of the endothelium in healthy persons of different age allowed us to establish that aging accompanied with a gradual worsening in the endothelium functioning with resulting increase in peripheral vascular resistance and blood pressure as well as decrease in the myocardial contractile activity. Such age shifts might be involved in pathogenesis of cardiovascular diseases, which prevalence is highly rises with increased age. Analysis of sex difference in the endothelium functioning showed a progressing lowering of the endothelium-dependent vasodilatory reaction to begin in the men as early as after 40 years of age. This leads to the decrease in the vasodilatory reserve with increase in peripheral vascular resistance and blood pressure. Worsening in the myocardial contractility in 40-year men can be also stipulated by changing in the endothelium synthetic activity that was evidenced by decrease in plasma levels of NO stable metabolites. In the women, such a lowering of the endothelium functional activity begins 10 years later and progresses more slowly compared to the men. The rate of worsening in the endothelium functioning in the men is twice of that in the women. Therefore, the elderly women have the endothelium to be 20 years "younger" than that in the elderly men, and perhaps namely this explains the better functioning of the cardiovascular system in the elderly women. So, a functional activity of the endothelium can be a main age and sex determinant, which stipulates well-known age and sex differences in prevalence of cardiovascular diseases and life expectancy. Prevention of the endothelium function disturbances might lead to the alignment of the differences between men and women in prevalence of cardiovascular diseases and life expectancy, decrease in general morbidity with improvement of life quality in elderly.

[Changes of nitric oxide level at different stages of primary open-angle glaucoma]. / Izmenenie urovnia oksida azota na raznykh stadiiakh pervichnoi otkrytougol'noi glaukomy.

The contents of NO stable metabolites in tears, and blood serum of the patients with different stages of open-angle glaucoma have been studied. The increasing of NO stable metabolite contents was found in tears, aqueous humor and blood serum during glaucoma progression. The depletion of glaucoma pathogenesis oxidative link was found at the terminal stage of the disease. The results of our investigation are proposed to be used for glaucoma diagnostic.