The purpose of our study was to determine the effect of a 35% hydrogen peroxide bleaching agent on the shear bond strength of metallic orthodontic brackets. Sixty premolars were randomly divided into 3 groups of 20 each. Teeth in group A were etched with 37% phosphoric acid before bonding metallic premolar brackets. Teeth in the other 2 groups were bleached with a 35% hydrogen peroxide in-offic...

A fiber optic sensor sensitive to refractive index changes of the outer region of the fiber cladding is presented. The sensor uses bent plastic optical fibers in different bending lengths to increase sensitivity. Measurements were made for low-fat milk, the refractive index of which is altered by some preservatives such as formaldehyde, hydrogen peroxide, and sodium carbonate. Concentrations of...

OBJECTIVE The aim of this study was to determine the oxidative status and antioxidative status of plasma of patients with complete hydatidiform mole (CHM) and to compare these values with normal pregnancy. METHOD Thirty-eight patients with CHM and 31 healthy pregnant women were enrolled in the study. To determine the antioxidative status of plasma, total antioxidant potential (TAOP) was calcu...

One-dimensional Pt nanostructures are of considerable interest for the development of highly stable and sensitive electrochemical sensors. This paper describes a self-interconnecting Pt nanowire network electrode (PtNNE) for the detection of hydrogen peroxide (H2O2) and glucose with ultrahigh sensitivity and stability. The as-prepared PtNNE consists of polycrystalline nanowires with high-index ...

The aim of this study was to determine the effect of acute intoxication with chlorfenvinphos on the liver reduced glutathione (GSH) level and the activities of two enzymes involved in glutathione metabolism, as well as the activity of catalase (CAT), glucose-6-phosphate dehydrogenase (G6PDH) and the level of liver hydrogen peroxide. The concentration of malondialdehyde (MDA) was determined as l...

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...

The aim of the study was to investigate the effect of bleaching on the colouration of tooth enamel and shear bond strength of orthodontic ceramic brackets based upon current whitening practice. The bleaching and bonding techniques were performed on extracted bovine teeth for the investigation of their colorimetric spectrum and the adhesive bond strength on surface enamel. One group was designat...

The health-promoting effects of fruit and vegetable consumption are thought to be due to phytochemicals contained in fresh plant material. Whether processed plant foods provide the same benefits as unprocessed ones is an open question. Melanoidins from heat-processed plums (prunes) were isolated and their presence confirmed by hydroxymethylfurfural content and browning index. Oxidative-induced ...

Streptococcus pneumoniae is a gram-positive bacterium which is a member of the normal human nasopharyngeal flora but can also cause serious disease such as pneumonia, bacteremia, and meningitis. Throughout its life cycle, S. pneumoniae is exposed to significant oxidative stress derived from endogenously produced hydrogen peroxide (H(2)O(2)) and from the host through the oxidative burst. How S. ...