Endotoxin was shown to depress neutrophil bactericidal activity while enhancing Nitro Blue Tetrazolium reduction and hexose monophosphate shunt activity. Separation of bactericidal action from oxidative metabolism suggests that the effect of endotoxin might involve the formation of reactive oxygen radicals such as superoxide. Chemiluminescence often accompanies metabolic activation of polymorph...

Human endothelial cells infected with Rickettsia rickettsii, the etiological agent of Rocky Mountain spotted fever, undergo striking morphological changes to the endoplasmic reticulum-outer nuclear envelope complex. These changes are accompanied by concurrent accumulation of intracellular peroxides. Both of these findings are consistent with the notion that cells undergo some form of oxidative ...

Chemical compositions of ginger oil as well as its antioxidant, anti-inflammatory and antinociceptive potential were evaluated in the present study. The main constituents as detected by GC/MS analysis was alpha-zingiberene which constituted 31% of the total area, ar-curcumene (15.4%) and a -sesquiphellandrene (14.02%). Ginger oil scavenged superoxide, DPPH, hydroxyl radicals and inhibited tissu...

Topical application of sodium arachidonate (50-200 micrograms/ml) or bradykinin (0.1-10 micrograms/ml) on the brain surface of anesthetized cats caused dose-dependent cerebral arteriolar dilation. This dilation was blocked by 67-100% in the presence of superoxide dismutase and catalase. These enzymes did not affect the changes in arteriolar diameter caused by alterations in arterial blood PCO2,...

The role of oxygen free radicals in the toxicity and antitumor effect of tumor necrosis factor was investigated in vivo. Treatment of non-tumor-bearing mice and mice bearing methylcholanthrene-induced sarcomas with bovine CuZn superoxide dismutase or recombinant human CuZn superoxide dismutase afforded significant protection to these mice from a subsequent challenge with recombinant human tumor...

Conventionally, the singly occupied molecular orbital (SOMO) of a radical species is considered to be the highest occupied molecular orbital (HOMO), but this is not the case always. In this study, we considered a number of radicals from smallest diatomic anion radicals such as superoxide anion radical to one-electron oxidized DNA related base radicals that show the SOMO is energetically lower t...

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...

Previous studies from our laboratory have shown that estrogens can protect against lipoprotein peroxidation and DNA damage. In this study, the mechanism of estradiol-17β (E2) action was investigated by comparing E2 with selective scavengers of reactive oxygen species (ROS) in terms of inhibition of 1) human low-density lipoprotein (LDL) peroxidation (measured by the diene conjugation method) an...