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Abstract: The main goal of the article is to familiarize specialists working in the field of medical devices (MDs) with existing approaches to the study of their biocompatibility, set out in the standards of the GOST(State Standard) ISO 10993 series. The concept of the GOST(State Standard) ISO 10993 series of standards lies in establishing the biological safety and functional effectiveness of MDs in the terms of biological risk, as necessary and sufficient conditions for biocompatibility of MDs in clinical application. The main attention in the general scheme of assessing the biological safety of MD is paid to the program of toxicological studies (tests), consisting of a set of methods that take into account the category, purpose, and duration of MD functioning.

The association between coronary heart disease (CHD) and social status has differed among societies in strength and direction. As years of schooling is a major determinant of socioeconomic status and dyslipidaemia a major CHD determinant, the purpose of this investigation is to estimate the association of years of schooling with plasma lipids and lipoproteins among samples from five countries representing different cultures, socio-political systems and stages of economic development.

Associations between selected risk factors and 7-year all-cause mortality were studied in 2,187 Russian women and 2,146 US women who were screened as part of a US-Russian collaborative program. The US women were screened during the period 1972-1976, while the Russian women were screened from 1978 to 1982. Cigarette smoking and elevated systolic blood pressure were associated with increased mortality in both samples. High density lipoprotein (HDL) cholesterol was inversely related to mortality in US women, but there was no association of HDL cholesterol with mortality in Russian women. Prevalent angina and electrocardiographic abnormalities were associated with mortality in both samples, but the relations achieved statistical significance only in the Russian sample. The problems of cigarette smoking and elevated blood pressure should be addressed with public health measures in both countries. The absence of an association between HDL cholesterol and mortality in the Russian sample should be investigated further.

Human and mouse peritoneal macrophages cultured in the presence of the blood serum of patients with documented coronary heart disease showed a 2- to 3-fold rise in levels of intracellular cholesterol ester and a 1.5- to 2-fold increase in those of free cholesterol and triglycerides. This effect was observed in 83% of cases, whereas the serum of healthy subjects induced the accumulation of lipids in macrophages only in 28% of cases. These data accord with previously published observations obtained on smooth muscle cells of human aortic intima. A direct correlation was found between the accumulation of cholesterol in macrophages and in cultured smooth muscle cells of human aortic intima. The accumulation of lipids in macrophages was dose dependent and increased with time. It is assumed that a culture of peritoneal macrophages may serve as a model for identifying an atherogenic potential of patients' blood serum.

Abstract We studied acception of cholesterol from Fu5AH hepatoma cells by blood serum from subjects with normal level of high-density lipoprotein cholesterol and hyperlipidemia (alone or in combination with other risk factors for coronary heart disease). Cholesterol-binding activity of high-density lipoproteins decreased in subjects with hyperlipidemia alone or in combination with excess body weight and/or arterial hypertension. Impairment of high-density lipoprotein activity was associated with changes in their phospholipid composition.

Abstract We studied the phospholipid composition of high-density lipoproteins in patients with coronary heart disease and hypercholesterolemia treated with simvastatin (Zocor, inhibitor of the key enzyme of cholesterol synthesis) and preparation of polyunsaturated phospholipids (lipostabil forte). Simvastatin produced a hypolipidemic effect and modulates the phospholipid composition of high-density lipoproteins (similarly to lipostabil forte). These changes contribute to functional activity of high-density lipoproteins in the reverse cholesterol transport.

The study demonstrated a decreased level of glucocorticoid receptors (GR) in peripheral blood lymphocytes from hypercholesterolemic subjects, and an elevated level in patients with acute myocardial infarction. In the lymphocytes with a high GR number, dexamethasone inhibited [3H]-thymidine and [3H]-acetate incorporation into DNA and cholesterol, respectively, in the same manner as in the control cells. On the other hand, a decreased GR number resulted in a less efficient dexamethasone inhibition of the incorporation of labeled compounds. These data showed that the sensitivity of lymphocytes to glucocorticoids changed only with a decrease of GR level.

A study was made of the regulation of the triglyceride hydrolysis catalysed by LPL from bovine milk, by the apoproteins from human plasma VLDL. Both isolated apolipoproteins, and those found on the surface of plasma VLDL particles, were investigated. A concentration-dependent activating action of apo C-II on the hydrolysis of emulsified triolein, and uncompetitive inhibition of VLDL triglyceride hydrolysis by apo C-III were found. It is suggested that VLDL lipolysis might be controlled in vivo trough the variation of the relative surface content of these enzymatic activity modulators.