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Historical development of mitral valve surgery at Petrovsky Russian Research Center for Surgery is described in the article. Evolution of artificial heart valves design and development of surgical techniques are presented.

Clinical and functional results of orthotopic cardiac transplantation are analyzed. It is demonstrated that case follow-up with special non-invasive methods (ECG, Holter monitoring, high-resolution ECG, EchoCG, dopler-EchoCG) is mandatory for detection of cardiac transplant function, early diagnosis of chronic rejection crisis, timely and optimal treatment tactics.

A study was made of the effect of the thymic factors thymosin (fraction 5) and tactivin on adrenocortical function of BALB/C mature mice. A single administration of thymosin at a dose of 1 micrograms/mouse causes a rise of the blood level of corticosterone in 3 h. Dexamethasone, a blocker of ACTH secretion, stops the thymosin effect. Thymosin does not influence adrenocortical production of corticosterone in vitro. A marked tendency to a decrease in the blood level of corticosterone is clearly observed 3 h after tactivin administration at doses of 0.1, 0.5 and 2.5 micrograms/mouse. Tactivin added to the adrenal glands in vitro causes dose-dependent suppression of corticosterone specific production. A conclusion is that both factors act in opposite directions on adrenal functioning, and their influence on the glands is mediated differently.

The concentrations of two glucocorticoids (corticosterone and cortisol) were investigated in plasma and tissues of adult albino male rats and preweaning pups. An increase in corticosterone concentration in plasma and kidneys during maturation was shown. A steroid undistinguishable from cortisol in TLC, RIA and HPLC tests was detected in pups. A conclusion is made that cortisol takes part in hormonal regulation of immature rats.

A study was made of the effect of cortisol administration on the 5th day of postnatal life on the development of the sexual system and adrenal function in female rats. Neonatal treatment with cortisol at a dose of 250 micrograms was shown to cause delayed maturity and a decrease in sex receptivity. This treatment also caused a decrease in adrenal and ovarian secretion in vitro of corticosterone and progesterone by rats aged 30 days and a decrease in the blood level of corticosterone of maturing animals. It was assumed that sex developmental disorder was determined by chronic deficiency of blood corticosterone.

The authors presented the results of a comparative study of ontogenesis of progesterone and estradiol production by the adrenal glands and ovaries in rats (from the 8th to the 60th days of life). A parallel study was made of the formation of the estradiol receptor system of the uterus. Immature rats adrenal glands in vitro were shown to produce much more progesterone than the ovaries. Progesterone production in the adrenal glands correlated with the intensity of corticosterone secretion. At the prepubertal age (the 8th-30th days of life) the adrenal glands and ovaries produced approximately the same amounts of estrogens determined as estradiol by a radioimmunoassay. The development of the uterine receptor system demonstrated parallelism with ontogenesis of the adrenal estrogen secreting activity. Such a regularity was undetectable for the ovaries. The authors discussed possible influence of the adrenal glands on the concentration of estradiol receptors in the uterus by means of estrogen synthesized by these receptors and immunologically similar to estradiol.

The thymic effect on the mouse gonadal endocrine function was studied. The serious gonadal endocrine dysfunction was seen in mice with genetically determined absence of the thymus. Thymectomy of healthy animals aged 3 days induces similar disorders. Transplantation of the thymus to the genetically thymus-free animals during the first days of the life returns this function to normal. It is concluded that the thymus plays an important role in the formation of the mouse gonadal endocrine function.

The paper is concerned with the effect of thymosin, a hormone secreted by the thymus (fraction 5), on the development of adrenocortical and sex gland functions in genetically athymic mice (nude mutation). Multiple administration of thymosin to mice in the 1st month of their life (0.1 microgram/mouse twice a week) caused the suppression of corticosterone production by the adrenal glands in adult mice aged 2 mos., a considerable rise of the blood level of testosterone in male mice and the reduction of the specific production of estradiol by the ovaries in females. A thymosin-mediated role in the interaction between the immune and endocrine systems in the period of development of their functions was discussed.

A study was made of the effect of neonatal cortisol treatment on maturity development, ontogenesis of the secretion of estradiol by the endocrine glands and its reception in the uterine cytosol in female rats. This treatment caused a considerable delay of the vaginal opening and the onset of the first estrus. An increase in estradiol secretion by the adrenal glands was observed in maturing rats of the study group. Estradiol secretion by the ovaries was not greatly changed. Neonatal cortisol treatment did not influence the development of estradiol reception in the uterine cytosol either. It was assumed that sex developmental disturbance was associated with estradiol hypersecretion by the adrenal glands.