著者

Masaki YAMAGATA Masaya HIRAYAMA Satoshi NISHISHITA Daisuke HORIKAWA Masashi ISHIKAWA

出版者

公益社団法人 電気化学会

雑誌

Electrochemistry (ISSN:13443542)

巻号頁・発行日

vol.81, no.10, pp.857-862, 2013-10-05 (Released:2013-10-05)

参考文献数

34

被引用文献数

3 7

---

The charge-discharge behavior of electric double-layer capacitors (EDLCs) composed of several ionic liquids and their lithium solutions were evaluated. The model EDLC cell with a Li+-containing ionic liquid electrolyte, LiTFSI/EMImFSI (LiTFSI = lithium bis(trifluoromethylsulfonyl)imide, EMImFSI = 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide), exhibited a higher discharge capacitance than the cell containing EMImFSI, whereas the discharge capacitance of the cell with LiTFSI/EMImTFSI was lower than that of the cell containing EMImTFSI. In addition, the cells composed of EMImBF4-based electrolytes displayed similar charge-discharge characteristics irrespective of the presence of the corresponding lithium salts. The distinctive results for the EDLCs with lithium-containing ionic liquid electrolytes are also discussed based on the application of the electrochemical impedance technique to model carbon electrodes in ionic liquids. According to the obtained differential capacitance of the model glassy carbon electrode in each ionic liquid electrolyte, the electric double-layer (compact layer) structure at the electrode/electrolyte interface depends on the component anion species of the ionic liquid and the co-existence of the anion and Li+.

著者

Kaoru KOBAYASHI Eri KAJIWARA Masayuki ISHIKAWA Hanaka MIMURA Hidenobu OKA Yoko EJIRI Masaya HOSODA Kan CHIBA

出版者

日本薬物動態学会 会長/日本薬物動態学会 DMPK編集委員長

雑誌

Drug Metabolism and Pharmacokinetics (ISSN:13474367)

巻号頁・発行日

vol.28, no.3, pp.265-268, 2013 (Released:2013-06-25)

参考文献数

18

被引用文献数

14

---

Treatment with benzbromarone (BBR), a potent uricosuric drug, can be associated with liver injury. Recently, we reported that culture of human hepatocellular carcinoma FLC-4 cells on micro-space cell culture plates could increase the functional expression of drug-metabolizing enzymes including CYP3A4 and CYP2C9, which are involved in 1′-hydroxylation and 6-hydroxylation of BBR, respectively. Therefore, we examined whether BBR and its two metabolites (1′-hydroxy BBR and 6-hydroxy BBR) have cytotoxic effects in FLC4 cells cultured on micro-space cell culture plates. The present study showed that BBR and 1′-hydroxy BBR, but not 6-hydroxy BBR, have cytotoxic effects in cells cultured on micro-space cell culture plates. BBR-induced cytotoxicity was decreased by CYP3A inhibitors (itraconazole and ketoconazole), an Nrf2 activator (tert-butylhydroquinone) and a GSH precursor (N-acetyl-L-cystein). In contrast, BBR-induced cytotoxicity was increased by a GSH biosynthesis inhibitor (buthionine sulfoximine) and an inhibitor of NAD(P)H quinone oxidoreductase 1 (dicoumarol). These results suggested that metabolic activation of 1′-hydroxy BBR via CYP3A, formation of quinone metabolites and the decrease in GSH levels were involved in the BBR-induced cytotoxicity observed in FLC4 cells cultured on micro-space cell culture plates.

著者

OZAWA Shogo SOYAMA Akiko SAEKI Mayumi FUKUSHIMA (UESAKA) Hiromi ITODA Masaya KOYANO Satoru SAI Kimie OHNO Yasuo SAITO Yoshiro SAWADA Jun-ichi

雑誌

Drug metabolism and pharmacokinetics (ISSN:13474367)

巻号頁・発行日

vol.19, no.2, pp.83-95, 2004-04-26

参考文献数

125

被引用文献数

3

著者

MASAYA

出版者

レムリアアイランドレコード

巻号頁・発行日

1998

著者

Tatara Masaya Doi Teruo

出版者

Ecological Society of Japan

雑誌

Ecological research (ISSN:09123814)

巻号頁・発行日

vol.9, no.1, pp.99-107, 1994-04

被引用文献数

12 61

著者

小林 正弥 コバヤシ マサヤ Kobayashi Masaya

出版者

千葉大学大学院人文社会科学研究科

雑誌

公共研究 (ISSN:18814859)

巻号頁・発行日

vol.2, no.4, pp.8-56, 2006-03-28

---

千葉大学公共研究センター21世紀COEプログラム「持続可能な福祉社会に向けた公共研究拠点」

著者

Kaoru KOBAYASHI Akane YOSHIDA Yoko EJIRI Sachiko TAKAGI Hanaka MIMURA Masaya HOSODA Tomokazu MATSUURA Kan CHIBA

出版者

日本薬物動態学会 会長/日本薬物動態学会 DMPK編集委員長

雑誌

Drug Metabolism and Pharmacokinetics (ISSN:13474367)

巻号頁・発行日

vol.27, no.5, pp.478-485, 2012 (Released:2012-10-26)

参考文献数

21

被引用文献数

18

---

Human hepatocellular carcinoma cell lines cultured in a monolayer show negligible activities of drug-metabolizing enzymes such as cytochrome P450s (CYPs) and UDP-glucuronosyltransferases (UGTs). Here, we show that culture of human hepatocellular carcinoma FLC-4 cells on 24-well plates arrayed with uniform micro-sized compartments on the bottom of the plates (micro-space cell culture plates) resulted in increased expression of drug-metabolizing enzymes (CYP1A2, CYP2C9, CYP3A4, UGT1A1, etc.) and nuclear receptors (pregnane X receptor, constitutive androstane receptor, etc.). When cells were treated with a typical CYP3A substrate (triazolam), CYP2C9 substrate (diclofenac) or UGT1A1 substrate (SN-38), large amounts of their metabolites were detected in the medium of cells cultured on micro-space cell culture plates. The formation of metabolites from triazolam, diclofenac and SN-38 was strongly inhibited by co-treatment with a CYP3A inhibitor (ketoconazole), CYP2C9 inhibitor (sulfaphenazole) and UGT1A1 inhibitor (ketoconazole), respectively. On the other hand, formation of metabolites was not observed in the medium of cells cultured in a monolayer. Finally, the cytotoxic effect of aflatoxin B1 was more potent in cells cultured on micro-space cell culture plates than in cells cultured in a monolayer. The results suggest that FLC-4 cells cultured on micro-space cell culture plates are useful for studying drug metabolism and drug-induced hepatotoxicity.

著者

Hattori Toshiaki Sakamoto Masaya

出版者

American Institute of Physics

雑誌

Applied physics letters (ISSN:00036951)

巻号頁・発行日

vol.90, no.26, pp.261106, 2007-06-25

被引用文献数

16

---

The authors have developed a method of real-time terahertz imaging in which image deformation due to nonuniformity of residual birefringence in the electro-optic (EO) sampling crystal is corrected. Real-time terahertz imaging using intense terahertz pulses and two-dimensional EO sampling can suffer from birefringence nonuniformity of the EO crystal since the birefringence is explicitly used for the linear detection of the terahertz field. In the proposed method, the distribution of the residual birefringence of the EO crystal is measured and used for image correction. Deformation-free images of the spatial profile of a focused terahertz pulse were obtained.

著者

He Shengtai Nakamura Hiroyuki Uehara Masato Miyazaki Masaya Maeda Hideaki

出版者

公益社団法人 化学工学会

雑誌

化学工学会 研究発表講演要旨集 化学工学会第37回秋季大会

巻号頁・発行日

pp.518, 2005 (Released:2006-03-18)

著者

Hiroshi Ikeda Kazuki Matsuo Yasunori Matsui Masaya Matsuoka Kazuhiko Mizuno

出版者

The Chemical Society of Japan

雑誌

Bulletin of the Chemical Society of Japan (ISSN:00092673)

巻号頁・発行日

pp.1104260289, (Released:2011-05-07)

参考文献数

67

被引用文献数

3

---

The mechanism of the Cope rearrangement of 1,5-hexadienes remains controversial. Two pathways for the rearrangement of 2,5-diphenyl-1,5-hexadiene have been debated over the past several decades. The first is a concerted route that takes place via a pericyclic transition state and the other is a stepwise process via a biradical intermediate or biradicaloid transition structure. In this study, we explored a new intramolecular trapping approach to examine the possible existence of the putative biradical that might intervene in the stepwise Cope rearrangement. For this purpose, a study was carried out in which a 1,5-hexadiene, bearing two lophyl radicals at C2 and C5 positions, moieties capable of trapping a putative biradical intermediate intramolecularly, was designed, generated, and characterized both experimentally and with density functional theory.

著者

Terai Hidenobu Shimizu Masami Ino Hidekazu Yamaguchi Masato Uchiyama Katsuharu Oe Kotaro Nakajima Kenichi Taki Junichi Kawano Masaya Mabuchi Hiroshi

出版者

THE SOCIETY OF NUCLEAR MEDICINE INC

雑誌

Journal of Nuclear Medicine (ISSN:01)

巻号頁・発行日

vol.44, no.10, pp.1612-1617, 2003-10

---

Left ventricular (LV) systolic function in hypertrophic cardiomyopathy (HCM) is usually normal. Late in the disease, however, LV systolic dysfunction and dilatation are recognized. Although abnormalities in cardiac sympathetic nerve activity in patients with HCM have been demonstrated using 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy, the changes of cardiac sympathetic nerve activity throughout the clinical course from typical to end-stage HCM are unclear. The objective of this study was to evaluate the relationship between abnormalities on 123I-MIBG myocardial scintigraphy and pathophysiologic changes in patients with HCM. Methods: We performed 123I-MIBG scintigraphy on 46 patients with HCM and 18 age-matched control subjects. The patients were categorized into 3 groups: 28 patients with normal LV systolic function (group A), 9 patients with LV systolic dysfunction (group B), and 9 patients with LV systolic dysfunction and dilatation (group C). With planar 123I-MIBG imaging, the heart-to-mediastinum ratio for early and delayed acquisitions and the washout rate were calculated. With SPECT, polar maps of the LV myocardium were divided into 20 segments. The regional uptake and washout rate were calculated from semiquantitative 20-segment bull's-eye analysis. Results: The early uptake was significantly lower in group C than in the control group (P < 0.01). The washout rate was progressively higher in group A, group B, and group C (P < 0.01). Reduced regional early uptake was found in 2.9 ± 3.4 (group A), 4.1 ± 4.7 (group B), and 7.4 ± 4.3 (group C) segments, respectively. In group C, regional early uptake was significantly reduced, predominantly in the interventricular septal wall, and regional washout rate was increased in the apex and lateral wall. Conclusion: These results suggest that cardiac sympathetic nerve abnormalities in patients with HCM may advance with development of LV systolic dysfunction and dilatation and that 123I-MIBG myocardial scintigraphy may be a useful tool for the evaluation of pathophysiologic changes in HCM.

著者

Itagaki Yoshiaki Kimura Naoko Yamanaka Masaya MUNETA Yoshihiro

出版者

THE SOCIETY FOR REPRODUCTION AND DEVELOPMENT

雑誌

The Journal of reproduction and development (ISSN:09168818)

巻号頁・発行日

vol.43, no.1, pp.53-58, 1997-02-01

被引用文献数

2

---

This study was undertaken to determine the relationship between the first cleavage division of <i>in vitro</i> produced (IVP) bovine embryos and the following few cleavage divisions in culture. The "early-", "intermediate-" and "late-" cleaving embryos presented at 22, 26 and 30 h post insemination (hpi) were cultured separately until they were fixed and stained with Hoechst 33342 at the end of each culture period (30, 48, 72, 96 and 120 hpi). Distributions of embryos that underwent the first cleavage at 22, 26 and 30 hpi were 21.5, 34.7 and 10.0%, respectively. No significant difference among the mean number of cells in the 3 groups was observed until 48 hpi. At 72 hpi, the number of cells in the early-cleaving embryos (10.8 ± 0.5) was higher than those in the intermediate- and late-cleaving embryos (8.7 ± 0.4 and 6.5 ± 0.6, respectively). Higher numbers of cells were also observed in the early-cleaving embryos (18.0 ± 1.5) at 120 hpi, compared with those in the intermediate- and late-cleaving embryos (12.5 ± 0.8 and 11.4 ± 1.5, respectively). More than 80% of the early- and intermediate-cleaving embryos had completed the second cleavage division at 48 hpi, whereas that of the late-cleaving embryos was lower (56.5%). No difference in the proportion of >8-cell embryos among the 3 groups was observed at 48 hpi (22.9 vs 24.7 vs 26.1%). However, the completion of the third cleavage in the early-cleaving embryos was higher than in the intermediate- and late-cleaving embryos at 72 hpi (65.4 vs 49.4 vs 25.0%), and from there onwards (96 hpi; 81.1 vs 63.2 vs 45.5%, 120 hpi; 83.6 vs 62.2 vs 65.0%). The proportion of >16-cell embryos in the early-cleaving embryos was also higher than that of the intermediate- and late-cleaving embryos between 96 hpi (18.9 vs 2.9 vs 0.0%) and 120 hpi (49.1 vs 22.0 vs 25.0%). Our results suggest that the development of IVP bovine embryos is possibly controlled as early as at the 2-cell stage, and the differences between the early and late cleaving embryos are associated with 1) the developmental delay or arrest of embryos during the second cleavage, and 2) the lengthening of the third cleavage, which seems to be related to the subsequent developmental ability of the embryos.