Oxygen free radicals effects

Low PA, Nickander KK. Oxygen free radical effects in sciatic nerve in experimental diabetes. Diabetes 1991 40 873-877. 

Benzoyl peroxide can help remove dead skin cells, which in turn prevents the pores from clogging up. It also kills the Propionibac-terium acnes bacterium that causes acne. It has anti-inflammatory effects and reduces oxygen free radicals and fatty acids on the skin. 

Coetzee, W.A. and Opie, L.Fl. (1992). Effects of oxygen free radicals on isolated cardiac myocytes from guinea-pig ventricle Electrophysiological studies. J. Mol. Cell. Cardiol. 24, 651-663. 

Tamura, K., Manabe, T., Ohshio, G., Ando, K., Yotsumoto, F., Kyogoku, T., Imanishi, K. and Tobe, T. (1991a). Effect of oxygen free radicals on the rat pancreas in vivo. Gastroenterology 100, A844. 

Mossman, B.T. and Marsh, J.P. (1985). Mechanisms of cell toxic injury by asbestos fibres role of oxygen free radicals. In In vitro Effects of Mineral Dusts (eds. E.G. Beck and J. Bignon) pp. 66-81. Springer Verlag, Berlin. 

The second way in which fats deteriorate is oxidative lipolysis. This is an entirely different process in which oxygen free radicals add across double bonds. Oxidative rancidity can be prevented or reduced by several different routes. One way is to ensure that no double bonds are present. Another is to use anti-oxidants that act as free radical traps. Exposure to oxygen and ultraviolet light should be avoided. Reducing the temperature has no effect since free radical processes have a zero activation energy. 

Oxidative rancidity is not necessarily a problem unless a polyunsaturated fat such as sunflower oil has been used. Where such a fat is used oxidative rancidity can occur and, as autoxidation occurs where the reaction becomes self-catalysing as oxygen free radicals react, some very unpleasant tastes can appear very quickly. In general, the effect of oxidation on biscuits at the end of their shelf life is that a cardboard taste starts to appear. 

SOD is a major oxygen free radical scavenging enzyme, which may therefore have beneficial effects in liver fibrosis. Through mannosylation or coupling to the polyanion DIVEMA, SOD was made more liver specific. Both conjugates showed superior inhibition of intrahep-atic ROS production in fibrotic rats as compared to unmodified SOD. DIVEMA-SOD, however, exhibited the most potent inhibitory effects [112]. Although their mode of action is most probably extracellular free radical scavenging, Man-SOD and DIVEMA-SOD are likely to... 

The drug has a half-life of 6-8 hours. It is extensively metabolized in the liver, and stereoselective metabolism of its two isomers is observed. Since metabolism of ( R)-carvedilol is influenced by polymorphisms in CYP2D6 activity and by drugs that inhibit this enzyme s activity (such as quinidine and fluoxetine, see Chapter 4), drug interactions may occur. Carvedilol also appears to attenuate oxygen free radical-initiated lipid peroxidation and to inhibit vascular smooth muscle mitogenesis independently of adrenoceptor blockade. These effects may contribute to the clinical benefits of the drug in chronic heart failure (see Chapter 13). 

Protection of vascular endothelial cells from oxygen free radical damages Enhancement of SOD, catalase and peroxidase in the cytosol of kidney Protection of pulmonary endothelium against free radicals in rabbits Protection of lipid peroxidation in liver and cardiac muscle in rats Inhibition of lipid peroxidation of rat liver and brain microsomes Inhibition of lipid peroxidation in serum and liver in rats Protective effect of ginsenosides on reperfusion injuries... 

Many medicinal plants contain chemical compounds called flavonoids. Some evidence suggests that flavonoids, also called bioflavonoids, can have beneficial effects on the body. Flavonoids may be able to help ward off bacteria and viruses and reduce inflammation. They may also be antioxidants, which are molecules that clear the body of harmful chemicals called oxygen free radicals. (Oxygen free radicals are highly reactive molecules that damage cells and have been associated with diseases such as cancer, diabetes, and cardiovascular disease.)... 

M. Kihara, J. D. Schmelzer, J. F. Poduslo, G. L. Curran, K. K. Nickander, and P. A. Low, Aminoguanidine effects on nerve blood flow, vascular permeability, electrophysiology, and oxygen free radicals, Proc. Natl Acad. Sci., USA 1991, 88, 6107-6111. 

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