Oxidation of Free Radicals with Peroxides or Oxygen

Formation of peroxides in amino acids and proteins exposed to oxygen free radicals.

Dilute aqueous solutions of BSA or lysozyme gave positive tests for peroxides after exposure to reactive oxygen species. The reactive species were generated by gamma-irradiation, reduction of H2O2 with Fe2+ ions or thermal decomposition of an azo compound. Peroxides were assayed by an iodometric method. Identification of the new groups as hydroperoxides was confirmed by their ability to oxidize...

Biochemistry of Oxygen and Its Free Radicals

Thrombolytic treatment in acute myocardial infarction achieves coronary patency in most patients.' Mortality in groups treated early after the onset of symptoms is significantly reduced,' but left ventricular function does not always improve.5 Myocardial necrosis during the period of vessel occlusion is partly responsible for the irreversible ventricular impairment that occurs even when the ves...

Oxygen free radicals and retinopathy of prematurity.

Oxygen free radicals and congestive heart failure.

Plasma lipid peroxides (malondialdehyde) and thiols were measured in 45 patients with congestive heart failure and 45 controls. Malondialdehyde concentrations were significantly higher in the patients with congestive heart failure (median 9.0 nmol/ml interquartile range (IQR) 7.9-10.2) than in the controls (median 7.7 nmol/ml (IQR 6.9-9.2)). Plasma thiols were significantly lower in congestive ...

Oxygen-Derived Free Radicals in Rats

Myocardial ischemia and reperfusion can evoke excitation of cardiac vagal afferent nerve endings and activation of a cardiogenic depressor reflex (Bezold-Jarisch effect). We postulate that oxygen-derived free radicals, which are well known to be produced during prolonged ischemia and reperfusion, contribute to this excitation. Hydroxyl radicals derived from hydrogen peroxide (H202) activate abd...