REACTIVE OXYGEN SPECIES & FREE RADICALS It is ironic that oxygen, an element indispensable for life [1], under certain situations has deleterious effects on human body [2]). Most of the potentially harmful effects of oxygen are due to the formation and activity of number of chemical compounds known as ROS, which have a tendency to donate oxygen to other substances. The causes of the poisonous p...

reactive oxygen species (ros)plays an important role in sperm motility. the physiological generation at low concentration induces beneficial effects on sperm functions and plays a significant role in sperm metabolism. meanwhile, the excessive generation of reactive oxygen species can overwhelm protective mechanism and triggers changes in lipid and protein layers of sperm plasma membrane, which ...

Free radicals induce oxidative stress in vivo, leading to various disorders and diseases. In the present study, the effect of oxygen pressure on the cytotoxicity induced by free radicals was studied. It was found that alkyl radicals markedly aggravated Jurkat cell apoptosis under low oxygen pressure and this was ascribed to a hypoxic condition caused by the consumption of oxygen by alkyl radica...

Free radical can be defined as a molecule or molecular fragments containing unpaired electron in the outer orbital, which react with nearby molecules to get stability. There are two types of them in the body: oxygen free radicals and nitrogen free radicals. Our body has an antioxidant defense system which prevents accumulation of these radicals. There is a balance between free radical produc...

apoptosis, a physiologic mechanism to eliminate unwanted cells, is also induced by ionizing irradiation, through production of free radicals. it has been demonstrated that antioxidants such as vitamin e are able to protect cells from damage caused by free radicals. taken together we found it reasonable to make an attempt to evaluate the protective effect of vitamin e against apoptosis. the irra...

The myocardium, like other tissues, has enzyme and non-enzyme systems to neutralize free radicals. The enzymes superoxide dismutase, catalase and glutathione peroxidase and glutathione reductase as well as the non-enzyme antioxidants vitamin E and ascorbic acid are the main antioxidants. Oxidants are produced by the mitochondria under normal conditions and by other sources under pathologic cond...

malondialdehyde (mda) is widely used as a biomarker for assessing oxidative stress in biomedical fields. lipid peroxidation is a chain phenomenon resulting in the formation of various active compounds that result in cellular damage. biomonitoring of mda has been used in both in-vivo and in-vitro studies as a key biomarker for various disease patterns including hypertension, diabetes, atheroscle...

background: mannitol is present in the ethyol ® (the trade name of amifostine) as an excipient. the mechanism of radioprotection of amifostine is radical scavenging. since mannitol is another known radical scavenger, we studied the probable additive or synergistic effect of mannitol on the effect of amifostine. material and methods: mice were irradiated with co-60 γ -ray in the presence 400mg/k...

Free Radicals and Ocular Disease p. 73 Active Oxygen Mechanisms of UV Inflammation p. 87 Oxygen-Free Radicals at Myocardial Level: Effects of Ischaemia and Reperfusion p. 99 Mechanisms of Atherosclerosis: Role of LDL Oxidation p. 113 Tissue Iron Overload and Mechanisms of Iron-Catalyzed Oxidative Injury p. 129 Free Radicals in the Pathophysiology of Pulmonary Injury and Disease p. 147 Lipid Per...