We have developed a method to determine serum scavenging-capacity profile against multiple free radical species, namely hydroxyl radical, superoxide radical, alkoxyl radical, alkylperoxyl radical, alkyl radical, and singlet oxygen. This method was applied to a cohort of chronic kidney disease patients. Each free radical species was produced with a common experimental procedure; i.e., uv/visible-light photolysis of free-radical precursor/sensitizer. The decrease in free-radical concentration by the presence of serum was quantified with electron spin resonance spin trapping method, from which the scavenging capacity was calculated. There was a significant capacity change in the disease group (n = 45) as compared with the healthy control group (n = 30). The percent values of disease’s scavenging capacity with respect to control group indicated statistically significant differences in all free-radical species except alkylperoxyl radical, i.e., hydroxyl radical, 73 ± 12% (p = 0.001); superoxide radical, 158 ± 50% (p = 0.001); alkoxyl radical, 121 ± 30% (p = 0.005); alkylperoxyl radical, 123 ± 32% (p>0.1); alkyl radical, 26 ± 14% (p = 0.001); and singlet oxygen, 57 ± 18% (p = 0.001). The scavenging capacity profile was illustrated using a radar chart, clearly demonstrating the characteristic change in the disease group. Although the cause of the scavenging capacity change by the disease state is not completely understood, the profile of multiple radical scavenging capacities may become a useful diagnostic tool.

Running title: IR-induced NO regulates tumor hypoxia and radioresistance.Abbreviations 3-NT, 3-nitrotyrosine; eNOS, endothelial nitric oxide synthase; ESR, electron spin resonance; H33342, Hoechst33342; iNOS, inducible nitric oxide synthase; LiNc- BuO, lithium 5,9,14,18,23,27,32,36-octa-n-butoxy-2,3-naphthalocyanine; L-NAME, N G -nitro-L-arginine methyl ester; nNOS, neuronal nitric oxide synthase ;NO, nitric oxide; NOS, nitric oxide 3 synthase; pO 2 , partial pressure of oxygen; positron emission tomography, PET. 4 ABSTRACTTumor hypoxia, which occurs mainly as a result of inadequate tissue perfusion in solid tumors, is a well-known challenge for successful radiotherapy. Recent evidence suggests that ionizing radiation (IR) upregulates nitric oxide (NO) production and that IR-induced NO has the potential to increase intratumoral circulation. However, the kinetics of NO production and the responsible isoforms for NO synthase in tumors exposed to IR remain unclear. In this study, we aimed to elucidate the mechanism by which IR stimulates NO production in tumors and the effect of IR-induced NO on tumor radiosensitivity. Hoechst33342 perfusion assay and electron spin resonance oxymetry showed that IR increased tissue perfusion and pO 2 in tumor tissue.Immunohistochemical analysis using two different hypoxic probes showed that IR decreased hypoxic regions in tumors; treatment with a nitric oxide synthase (NOS) inhibitor, L-NAME, abrogated the effects of IR. Moreover, IR increased endothelial NOS (eNOS) activity without affecting its mRNA or protein expression levels in SCCVII-transplanted tumors. Tumor growth delay assay showed that L-NAME decreased the anti-tumor effect of fractionated radiation (10 Gy × 2). These results suggested that IR increased eNOS activity and subsequent tissue perfusion in tumors. Increases in intratumoral circulation simultaneously decreased tumor hypoxia. As a result, IR-induced NO increased tumor radiosensitivity. Our study provides a new insight into the NO-dependent mechanism for efficient fractionated radiotherapy.

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The natural existence of the irradiation markers, namely, 2-decylcyclobutanone (2-DCB) and 2-dodecylcyclobutanone (2-dDCB), in nutmeg (Myristica fragrans) has recently been reported. In this study, 2-DCB and 2-dDCB were extracted from nutmeg of 5 different origins using supercritical fluid extraction (SFE). A 50-kGy irradiated sample was used to optimize the parameters of SFE and solid-phase extraction. The irradiated samples were analysed by gas chromatography-mass spectrometry, whereas the non-irradiated samples were analysed with high-resolution gas chromatography-mass spectrometry. Both 2-DCB and 2-dDCB were detected and identified in the irradiated samples at 5 kGy or greater. However, neither was present in the non-irradiated samples. Moreover, although the concentrations of 2-DCB and 2-dDCB were significantly reduced, a positive identification was obtained in irradiated nutmeg even after 30 weeks of storage.

We investigated the fate of radioactive cesium ((134)Cs plus (137)Cs) during the production of tofu, natto, and nimame (boiled soybean) from a contaminated Japanese soybean cultivar harvested in FY2011. Tofu, natto, and nimame were made from soybean grains containing radioactive cesium (240 to 340 Bq/kg [dry weight]), and the radioactive cesium in the processed soybean foods and in by-product fractions such as okara, broth, and waste water was measured with a germanium semiconductor detector. The processing factor is the ratio of radioactive cesium concentration of a product before and after processing. For tofu, natto, nimame, and for the by-product okara, processing factors were 0.12, 0.40, 0.20, and 0.18, respectively; this suggested that these three soybean foods and okara, used mainly as an animal feed, can be considered safe for human and animal consumption according to the standard limit for radioactive cesium of soybean grains. Furthermore, the ratio of radioactive cesium concentrations in the cotyledon, hypocotyl, and seed coat portions of the soybean grain was found to be approximately 1:1:0.4.