It has been proposed that the mutagenic activity associated with the ascorbic acid autoxidation system may involve hydrogen peroxide and peroxide radicals. We report here that the system may involve hydrogen peroxide and peroxide radicals. We report there that the mutagenic effect may also partially reside in as yet unknown secondary products. The observed mutagenicity of 2,3-diketogulonic acid...

introduction: the present study evaluated the element distribution in completely set calcium-enriched mixture (cem) cement after application of 35% carbamide peroxide, 40% hydrogen peroxide and sodium perborate as commercial bleaching agents using an energy-dispersive x-ray microanalysis (edx) system. the surface structure was also observed using the scanning electron microscope (sem). methods ...

The irreversible inhibition of catalase by 3-amino-l, 2,4-trizole and a group of related inhibitors (1) in the presence of a continuous supply of hydrogen peroxide has been shown to result from a reaction of the inhibitors with catalase-hydrogen peroxide complex I (2) in which 1 mole of inhibitor is incorporated into the enzyme protein for each mole of catalase heme that has reacted (1). The ki...

BACKGROUND Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells. PRINCIPAL FINDINGS Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 c...

This in vivo study determined the kinetics of 3% hydrogen peroxide in a bleaching gel within the first hour. The material used in this study was 3% hydrogen peroxide gel (Perfecta 3/15, Premier Dental Products Co) and the study involved 10 subjects who met the inclusion and exclusion criteria. Each subject wore the tray with gel six different times on separate days. Evaluation of the remaining ...

A range of some Iranian monofloral honeys were assayed for antibacterial activity with and without hydrogen peroxide which is inactivated by the addition of catalase. I t was found that the high amount of antibacterial activity in honeys was due to a factor other than hydrogen peroxide. The test microorganism Staphylococcus aureus, was not inhibited by the acidity or the osmolarity of the h...

Hydrogen peroxide induces oxidation and consequently inactivation of many protein tyrosine phosphatases. It was found that hydrogen peroxide, in the presence of carboxylic acids, was efficiently activated to form even more potent oxidant - peroxy acid. We have found that peroxytetradecanoic acid decreases the enzymatic activity of CD45 phosphatase significantly more than hydrogen peroxide. Our ...