The antioxidative action of fibrinogen and the implications of this effect on platelet aggregation.

Purified fibrinogen strongly acts as an antioxidant by inhibiting the chemiluminescent emission developed in vitro, in a cell-free system composed of luminol and hydrogen peroxide. The antioxidative action of fibrinogen depends directly on its concentration, even in the presence of human serum. On the other hand, the platelet aggregation is an important source of oxygen free radicals.

Estimation of oxidative stress in cardiovascular diseases.

Patients with mild and severe cardiovascular diseases showed a significant disturbance of the redox equilibrium, manifested by increases of lipid peroxides and decreases of plasma total antioxidants. When the resulting oxidative stress is associated with ECG changes characteristic of "coronary disease" it indicates an acceleration of atherosclerosis, in the initial phase (cellular involvement, migration, proliferation) and an additional thrombogenic risk in the "ischemic phase". When oxidative stress is associated with chronic heart failure, it indicates a progressive form with replacement fibrosis.

Steroid hormones may modulate the chemiluminescence emission produced by polymorphonuclear leukocytes.

Steroid hormones, testosterone and estrone may modify the in vitro chemiluminescence (CL) produced by polymorphonuclear leukocytes (PMNL) during phagocytosis. These changes (increases or decreases) depended on the age and health condition of the donor, but not on sex. Generally, these steroid hormones increase the PMNL CL emission at concentrations lower than 10(-5) M, but decrease it at higher levels.

The negative impact of oxidative stress in chronic cardiac failure and coronary heart disease calls for a new pathophysiologic and therapeutic approach.

Oxidative stress, when associated with ECG aspects of "coronary disease", indicates an accelerated course of atherosclerosis in the onset phase (by cellular involvement, migration, proliferation, etc.) and an additional thrombogenic risk in the "ischemic disease" phase, when associated with chronic cardiac failure, it indicates a progressive form with "replacement fibrosis". The therapy that reduces the oxidative stress can slow down the physiopathologic process, and clinically improves the patients' condition and prognosis.

Cardiothyreosis.

In the present study: (a) physiopathology, (b) clinics, and (c) therapy of cardiothyreosis are discussed. (a) The hyperkinetic syndrome, the earliest clinical sign in thyrotoxicosis (vasodilatation, increase in inotropism, automatism, etc.), is mediated by a two-fold increase in the number of beta-receptors, and supported by an adequate synthesis of ATP and creatinphosphate (CP) in the young and, to a lesser extent, in the elderly.