One approach to enhance the disinfection of root canals in endodontic treatment is ultrasonic irrigation with sodium hypochlorite. Reactive oxygen species, such as hydroxyl radical, are generated by biological defense systems to kill invading bacteria. Ultrasonic irrigation with hydrogen peroxide may be a promising option to increase hydroxyl radical generation. We examined the bactericidal eff...

The kinetics of the iodine oxidation by hydrogen peroxide is a complicated function of the concentrations of iodine, hydrogen peroxide, perchloric acid and iodate. A proposed model in eight steps explains the new experimental results. It explains also the effect of the concentrations at the steady state of the hydrogen peroxide decomposition catalyzed by iodine and iodate. Without iodate added ...

While gustatory sensing of the five primary flavors (sweet, salty, sour, bitter, and savory) has been extensively studied, pathways that detect non-canonical taste stimuli remain relatively unexplored. In particular, while reactive oxygen species cause generalized damage to biological systems, no gustatory mechanism to prevent ingestion of such material has been identified in any organism. We o...

Oxidative stress induced by reactive oxygen species (ROS) is the major cause of degenerative disorders including aging and disease. In this study, we investigated whether Cordyceps militaris extract (CME) has in vitro protective effects on hydrogen peroxide-induced oxidative stress in human dermal fibroblasts (HDFs). Our results showed that the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scave...

BACKGROUND We hypothesized that cord blood hydrogen peroxide (H2O2) could be utilized to predict the severity of neonatal hyperbilirubinemia. METHODS We prospectively enrolled term or near-term healthy neonates. Cord blood and capillary blood at three days of age were measured for hydrogen peroxide and bilirubin concentrations. For newborns with hyperbilirubinemia, further blood samples were ...

OBJECTIVE This study was performed to determine the effect of the tocotrienol-rich fraction on the lifespan and oxidative status of C. elegans under oxidative stress. METHOD Lifespan was determined by counting the number of surviving nematodes daily under a dissecting microscope after treatment with hydrogen peroxide and the tocotrienol-rich fraction. The evaluated oxidative markers included ...

A detailed investigation was carried out of the effects of porphyrin composition on the activity and selectivity of iron(III) porphyrin catalysts used or the epoxidation of cyclooctene by hydrogen peroxide. Under conditions where the formation of -oxo-dimers can be avoided, the mechanism f cyclooctene epoxidation and hydrogen peroxide decomposition are identical for all of the porphyrin catalys...

Aim This study aims to evaluate the color change in human enamel bleached with three different concentrations of hydrogen peroxide, containing pineapple extract as an additive in two different timings, using reflectance spectrophotometer. Background The study aimed to investigate the bleaching efficacy on natural teeth using natural enzymes. Materials and Methods Baseline color values of 10...

To explore the possibility of using graphene based biosensor, adsorption of hydrogen peroxide on graphene has been investigated using density functional theory. The electronic properties of defect free and defective graphene in the presence of different number of hydrogen peroxide have been studied. The graphene with the most stable configuration defect named as SW defect is considered. The hig...

It is well established that oxidative stress is an important cause of cell damage associated with the initiation and progression of many diseases. Consequently, all air-living organisms contain antioxidant enzymes that limit oxidative stress by detoxifying reactive oxygen species, including hydrogen peroxide. However, in eukaryotes, hydrogen peroxide also has important roles as a signaling mole...