BACKGROUND Airway inflammation represents the basis of respiratory allergic disease and is generally associated with increased oxidative stress. As a consequence of successful treatment leading to hyposenzibilization and remission of symptoms, decrease of reactive oxygen formation is expected. MATERIAL/METHODS This preliminary study evaluates the production of oxygen free radicals in white bl...

The addition of hydralazine (1-hydrazinophthalazine) to rat liver mitochondria metabolizing malate/glutamate causes formation of a carbon-centered free radical which was spin-trapped with phenyl-t-butylnitrone (PBN) or dimethylpyrrolidine-N-oxide (DMPO). The coupling constants of the spin-trapped free radical were AN = 16.1, AH beta = 4.6 G for PBN and AN = 15.9, AH beta = 18.9 G for DMPO-trapp...

Hispidin oligomers are styrylpyrone pigments isolated from the medicinal fungi Inonotus xeranticus and Phellinus linteus. They exhibit diverse biological activities and strong free radical scavenging activity. To rationalize the antioxidant activity of a series of four hispidin oligomers and determine the favored mechanism involved in free radical scavenging, DFT calculations were carried out a...

Background: Epigallocatechin gallate (EGCG), a major constituent of green tea, has been introduced as a potent free radical scavenger and can effectively reduce free radical-induced lipid peroxidation. Since free radical injury plays an important role in neuronal damage in Parkinson’s disease (PD), this study examined whether EGCG administration would reduce functional asymmetry in an experimen...

Running title: Metabolism of cyclic nitrone superoxide adducts Manuscript Click here to view linked References 2 Abstract Reactive oxygen species (ROS) are by-products of aerobic metabolism involved in the onset and evolution of various pathological conditions. Among them, superoxide radical is of special interest as the origin of several damaging species such as H 2 O 2 , hydroxyl radical, or ...

The aim of this study is to evaluate the status of endogenous antioxidant defense system in H. pylori-infected endoscopically diagnosed chronic duodenal ulcer patients through the assessment of certain oxidative stress biomarkers. These biomarkers namely plasma malodialdehyde (MDA) and blood activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) are to be evaluated before and...

Free radicals intermediates are formed on the surface of metal oxide semiconductors, namely Ti02 and Fe203, following the light-induced charge separation upon band-gap illu-mination. These radicals appear to adhere strongly to the ~.urfaces of the small colloidal particles (diameters between 5 and 20 nm) employed in this study. A second electron-transfer step yielding the observed end-products ...

acterizing free radicals in chemistry, biology and medicine, is detection by EPR spectroscopy. However, due to their high reactivity and short half-lives, direct EPR detection of many free radicals (e.g., superoxide, hydroxyl radical, alkyl radicals, etc.) is virtually impossible in solution at room temperature. Spin trapping is a technique developed in the late 1960s in which a nitrone or nitr...

Free-radical metabolites can be generated metabolically by a one-electron reductase-catalyzed reaction or a "peroxidase" catalyzed oxidation or by photoactivation of a wide variety of aromatic xenobiotics. Radicals may also be generated during lipid peroxidation. Some radicals can react with DNA or bind covalently or noncovalently as a dismutation product or as a dimer, trimer or polymeric prod...

We conducted this study to determine whether physiological changes in potassium concentration affect free radical formation by vascular cells. We assessed the effects of potassium on reactive oxygen species formed by cultured endothelial and monocyte/macrophage cells or freshly isolated human white blood cells by cytochrome c reduction or luminol chemiluminescence, respectively. Reducing potass...