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Tsukuba, Japan

Doi K.,Tsukuba Center Inc. | Doi K.,University of Tokyo | Uetsuka K.,Ibaraki University
Journal of Toxicologic Pathology | Year: 2014

Among the many mycotoxins, T-2 toxin, citrinin (CTN), patulin (PAT), aflatoxin B1 (AFB1) and ochratoxin A (OTA) are known to have the potential to induce dermal toxicity and/or tumorigenesis in rodent models. T-2 toxin, CTN, PAT and OTA induce apoptosis in mouse or rat skin. PAT, AFB1 and OTA have tumor initiating properties, and OTA is also a tumor promoter in mouse skin. This paper reviews the molecular mechanisms of dermal toxicity and tumorigenesis induced in rodent models by these mycotoxins especially from the viewpoint of oxidative stress-mediated pathways. © 2014 The Japanese Society of Toxicologic Pathology. Source

Amano T.,Tsukuba Center Inc. | Abe T.,Dai Nippon Printing
Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics | Year: 2015

It is very difficult to predict how multilayer defects known as "phase defects" impact on wafer printed image when embedded in an extreme ultraviolet (EUV) mask. Therefore, researchers have reported many techniques to analyze and characterize phase defects using scanning probe microscopes (SPMs) and phase defect inspection tools that employ deep ultraviolet or EUV optics. To characterize the phase defects using SPM or other inspection tools, preparing and employing a programmed phase defect mask is a practical way to address the task because the locations, sizes, and quantity of phase defects can be defined to fit experiments. For this study, a programmed phase defect mask was prepared to investigate the size uniformity of the programmed phase defects. The designed phase defects were holes 40-, 50-, 70-, or 80-nm-wide and 4.5-nm-deep. Using a SPM, the phase defects were measured for their depths and widths before and after coating with the multilayer. As a result, variations in the measured depths and widths were much smaller than the defect-to-defect variations, reflecting measurement repeatability. In addition, the variations in the depths and widths of the phase defects after multilayer coating were larger than before coating. It was also found that a given group of phase defects exhibited significant variations in depth and width after multilayer coating, even if they were the same prior to coating. This result indicated that it is difficult to estimate precoating phase defect sizes based on measurements after the multilayer is coated. © 2015 American Vacuum Society. Source

Zhang Y.,Tsukuba Center Inc.
Journal of medicinal food | Year: 2010

We previously reported that chicken collagen hydrolysate (CCH) has strong angiotensin I converting enzyme (ACE) inhibitory activity and antihypertensive effects on spontaneously hypertensive rats. Here, we investigated the chronic therapy effects of CCH on blood pressure and vascular relaxation in a cardiovascular damage model of Wistar-Kyoto rats induced by N-nitro-l-arginine methyl ester (L-NAME). Following co-treatment with CCH for 4 weeks, the increment of systolic blood pressure was suppressed significantly. At 8 weeks, the vasorelaxation of thoracic aorta increased significantly, and cardiovascular damage was ameliorated. The concentration of soluble intercellular adhesion molecule-1 (ICAM-1) in blood was reduced significantly by long-term administration of CCH, whereas the nitric oxide concentration was increased significantly at 1 hour post-treatment. The results suggest that beneficial effects of CCH result from antihypertensive function, but also from inhibition of cardiovascular damage to the endothelial cells via its ACE inhibitory activity and regulation of nitric oxide and ICAM-1, which suggests that CCH may be useful as a medicinal food for patients with cardiovascular disease. Source

Goto K.,Waseda University | Maemura H.,Tsukuba Center Inc. | Takamatsu K.,Ryutsu Keizai University | Ishii N.,University of Tokyo
Journal of Strength and Conditioning Research | Year: 2011

Intramuscular carnosine buffers protons (H+) in skeletal muscle. We examined the effects of supplementation with chicken breast meat extract (CBEX) containing carnosine and anserine on hormonal responses to resistance exercise. Twenty-two men were assigned to a CBEX drink group (CBEX containingtotal 2 g of carnosine and anserine) (n = 14) or a placebo drink group (n = 8). The subjects ingested the prescribed drink (100 mL) twice daily for 30 days without physical training. Before and after the supplementation period, the subjects completed 5 sets of bilateral knee extension exercises (with a 90-s rest between sets). The magnitude of the increase in exerciseinduced free testosterone did not change significantly after supplementation ineither group. The blood lactate response to exercise was attenuated after supplementation in both groups (p < 0.05). In the CBEX group, the plasmaepinephrine and norepinephrine concentrations after exercise were significantly lower after supplementation (p < 0.05). The serum growth hormone response to exercise was also reduced in the CBEX group after supplementation (delta value: 5.4±1.9 ng/mL [pre] vs. 1.6±0.5 ng/mL [post],p = 0.05). No significant differences in exercise-induced strength reduction (fatigue index) were observed in the 2 groups after supplementation. These results suggest that short-term supplementation with CBEX attenuates the exercise-induced epinephrine, norepinephrine, and growth hormone responses. ©2011 National Strength and Conditioning Association. Source

Fattori A.,University of Bath | Peter L.M.,University of Bath | Wang H.,University of Bath | Miura H.,Tsukuba Center Inc. | Marken F.,University of Bath
Journal of Physical Chemistry C | Year: 2010

The indoline dyes D102, D131, D149, and D205 have been characterized when adsorbed on fluorine-doped tin oxide (FTO) and TiO2 electrode surfaces. Adsorption from 50:50 acetonitrile-tert-butanol onto fluorine-doped tin oxide (FTO) allows approximate Langmuirian binding constants of 6.5×104, 2.0×103, 2.0×104, and 1.5×104 mol-1 dm3, respectively, to be determined. Voltammetric data obtained in acetonitrile/0.1 M NBu 4PF6 indicate reversible one-electron oxidation at E mid = 0.94, 0.91, 0.88, and 0.88 V vs Ag/AgCl(3 M KCl), respectively, with dye aggregation (at high coverage) causing additional peak features at more positive potentials. Slow chemical degradation processes and electron transfer catalysis for iodide oxidation were observed for all four oxidized indolinium cations. When adsorbed onto TiO2 nanoparticle films (ca. 9 nm particle diameter and ca. 3 μm thickness on FTO), reversible voltammetric responses with Emid = 1.08, 1.16, 0.92, and 0.95 V vs Ag/AgCl(3 M KCl), respectively, suggest exceptionally fast hole hopping diffusion (with Dapp > 5×10-9 m2 s-1) for adsorbed layers of all four indoline dyes, presumably due to π-π stacking in surface aggregates. Slow dye degradation is shown to affect charge transport via electron hopping. Spectroelectrochemical data for the adsorbed indoline dyes on FTO-TiO2 revealed a red-shift of absorption peaks after oxidation and the presence of a strong charge transfer band in the near-IR region. The implications of the indoline dye reactivity and fast hole mobility for solar cell devices are discussed. © 2010 American Chemical Society. Source

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