Site-specific DNA damage by Cu(II) plus H2O2 was investigated by a DNA-sequencing technique. Cu(II) plus H2O2 induced strong DNA cleavage even without piperidine treatment. Piperidine-labile sites were induced frequently at thymine and guanine residues and rarely at adenine residue. A Cu(I)-specific chelating agent, bathocuproine, inhibited the DNA damage. Neither ethanol nor mannitol inhibited...

Understanding trends in selectivity is of paramount importance for multi-electron electrochemical reactions. The goal of this work is to address the issue of 2e(-) versus 4e(-) reduction of oxygen on metal surfaces. Using a detailed thermodynamic analysis based on density functional theory calculations, we show that to a first approximation an activity descriptor, ΔGOH*, the free energy of adso...

The oxidation of acetaminophen (4'-hydroxyacetanilide) to the corresponding N-acetyl-p-benzoquinone imines by plant and mammalian peroxidases is discussed. The acetaminophen free radical (N-acetyl-4-aminophenoxyl) has been reported as an intermediate. It is very reactive and forms melanin-like polymeric products. Application of a fast-flow system makes it possible to detect the transient specie...

background the aim of the present study was to investigate the effect of ginger and glibenclamide on oxidative stress markers. oxidative stress is caused by an unbalance between a relative overload of oxidants and depletion of antioxidants, as implicated in the pathogenesis of several chronic diseases, including atherosclerosis and diabetes mellitus. regarding the role of oxidative stress in th...

background & aim: free radicals play a crucial role in the development of tissue damage in various human diseases such as cancer, aging, neurodegenerative disease, malaria and arteriosclerosis, and pathological events in living organisms. antioxidants may have an important role in the prevention of these diseases. the aim of this study is to evaluate potency of scavenging of dpph free radic...

The CH2-linked glycoform of rheumatoid IgG is abnormal in having a reduced galactose content. This has been postulated to be a synthetic defect due to a decrease in the level of rheumatoid B cell galactosyltransferase. However, more recent work has indicated that agalactosylation may be common to chronic inflammatory diseases. In this work we have investigated the effect of oxygen free radicals...

Ischemia-reperfusion damage is a complex pathological process that begins with tissue anoxia and continues with the production of free oxygen radicals, expanding with the inflammatory response. The literature suggests the importance of antioxidant and anti-inflammatory treatment to treat ischemia-reperfusion-related tissue damage.

During the last years, special emphasis was directed towards the relation between the molecular and cellular alterations produced by free oxygen radicals and the normal and pathologic implications of nitric oxide. Moreover, lately it is believed that a true radical cascade might exist between the reactive species of oxygen and nitrogen during stress of various causes. In this way, their success...

OBJECTIVE Previous studies have reported that the beta and alpha adrenoceptor blocker carvedilol has unique protective effects on free radical-induced myocardial injury. The aim of this study was to examine how carvedilol regulates reactive-oxygen-species-mediated signaling and decreases red blood cell membrane damage in heart perfusion and in a rheological model. METHODS The ischemia-reperfu...