Minako Nyui

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We investigated the amount and distribution of hydrogen peroxide (H(2)O(2)) generated in a solid gelatin sample irradiated by heavy ion (carbon) beam. We irradiated the gelatin sample, which contained a nitroxyl radical (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, TEMPOL), with a 290-MeV/nucleon carbon beam (~128 Gy). To verify the distribution of(More)
Temperature-dependent free radical reactions were investigated using nitroxyl radicals as redox probes. Reactions of two types of nitroxyl radicals, TEMPOL (4-hydroxyl-2,2,6,6-tetramethylpiperidine-N-oxyl) and carbamoyl-PROXYL (3-carbamoyl-2,2,5,5-tetramethylpyrrolidine-N-oxyl), were tested in this paper. Heating a solution containing a nitroxyl radical and(More)
Quantitative detection of free radical reactions induced by low linear-energy-transfer (LET) irradiation in an aqueous solution was attempted using nitroxyl radicals. The stability and reactivity of reaction mixtures containing a nitroxyl radical and a hydrogen donor, i.e., glutathione (GSH), nicotinamide adenine dinucleotide (NADH), or nicotinamide adenine(More)
In vivo radioprotection of C3H mice by i.p. administration of Zn-, Mn-, Cu-, or Se-containing heat-treated Saccharomyces serevisiae yeast sample was examined. The 30-day survival of the group treated 30 min before 7.5 Gy whole-body X-irradiation with mineral-containing yeast powders suspended in 0.5% methylcellulose was significantly higher than that of(More)
The scavenging activity of rat plasma against hyperthermia-induced reactive oxygen species was tested. The glutathione-dependent reduction of a nitroxyl radical, 4-hydroxyl-2,2,6,6-tetramethylpiperidine-N-oxyl, which was restricted by adding superoxide dismutase or by deoxygenating the reaction mixture, was applied to an index of superoxide (O2 (•-))(More)
We previously showed that free radicals and oxidative stress are involved in radiation-induced skin reactions. Since vitamin E (VE) is a particularly important lipophilic antioxidant, VE-deficient mice were used to examine its effects on radiation-induced skin damage. The VE content of the skin was reduced to one fourth of levels of normal mice. Neither the(More)
The glutathione (GSH)-mediated superoxide (O2•-) generation in an aqueous solution and relation of hydrogen peroxide (H2O2) and effect of catalase were investigated. GSH-induced O2•- generation in hyperthermal temperatures was measured by the nitroblue tetrazolium (NBT) mehod. Heating an aqueous solution containing GSH caused superoxide from dissolved O2.(More)
Oral mucositis (OM) is a common and painful complication of radiotherapy for head and neck cancer. Hangeshashinto (HST), a Japanese traditional medicine, is known to alleviate radiotherapy- and/or chemotherapy-induced OM; however, the detailed mechanism has not yet been clarified. The aim of the present study was to clarify the details of the antioxidative(More)
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