著者

Koichi Tomoda Kaoru Kubo Kazuo Hino Yasunori Kondoh Yasue Nishii Noriko Koyama Yoshifumi Yamamoto Masanori Yoshikawa Hiroshi Kimura

出版者

The Japanese Society of Toxicology

雑誌

The Journal of Toxicological Sciences (ISSN:03881350)

巻号頁・発行日

vol.39, no.2, pp.331-337, 2014-04-01 (Released:2014-03-18)

参考文献数

23

被引用文献数

5 7

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Cigarette smoke induces skeletal muscle wasting by a mechanism not yet fully elucidated. Branched-chain amino acids (BCAA) in the skeletal muscles are useful energy sources during exercise or systemic stresses. We investigated the relationship between skeletal muscle wasting caused by cigarette smoke and changes in BCAA levels in the plasma and skeletal muscles of rats. Furthermore, the effects of BCAA-rich diet on muscle wasting caused by cigarette smoke were also investigated. Wistar Kyoto (WKY) rats that were fed with a control or a BCAA-rich diet were exposed to cigarette smoke for four weeks. After the exposure, the skeletal muscle weight and BCAA levels in plasma and the skeletal muscles were measured. Cigarette smoke significantly decreased the skeletal muscle weight and BCAA levels in both plasma and skeletal muscles, while a BCAA-rich diet increased the skeletal muscle weight and BCAA levels in both plasma and skeletal muscles that had decreased by cigarette smoke exposure. In conclusion, skeletal muscle wasting caused by cigarette smoke was related to the decrease of BCAA levels in the skeletal muscles, while a BCAA-rich diet may improve cases of cigarette smoke-induced skeletal muscle wasting.

著者

Hisaji SHIMIZU Atsuhisa TAKEKOSHI Osamu TANIGUCHI Hiroshi KIMURA Ushio KAWABE

出版者

The Japan Society of Mechanical Engineers

雑誌

Bulletin of JSME (ISSN:00213764)

巻号頁・発行日

vol.15, no.88, pp.1299-1305, 1972 (Released:2008-02-15)

参考文献数

2

被引用文献数

1 2

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A superconductive magnet is generally thought unsuitable for a magnetic bearing because this magnet must be placed in liquid helium. The authors propose a new rotor-supporting system suing the strong magnetic field of a superconductive magnet. The experimental prototype was manufactured and its performances were evaluated experimentally and theoretically. The prototype consists of a cryostat, superconductive magnets, a rotor, mechanical auxiliary bearing, and so on. This newly devised cryostat can transmit an attractive force to a rotor which is placed in a normal temperature atmosphere. The bearing can suspend a rotor with hundreds of kilograms in the thrust direction using a mechanical auxiliary bearing in the radial direction. Besides, complete levitation is made possible when the currents of magnets are controlled automatically.

著者

Daisuke Muramatsu Hiroshi Kimura Kaoru Kotoshiba Makoto Tachibana Yoichi Shinkai

出版者

日本細胞生物学会

雑誌

Cell Structure and Function (ISSN:03867196)

巻号頁・発行日

pp.16013, (Released:2016-10-12)

被引用文献数

1 14

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Pericentric regions form epigenetically organized, silent heterochromatin structures that accumulate histone H3 lysine 9 tri-methylation (H3K9me3) and heterochromatin protein 1 (HP1), a methylated H3K9-binding protein. At pericentric regions, Suv39h is the major enzyme that generates H3K9me3. Suv39h also interacts directly with HP1. However, the importance of HP1 interaction for Suv39h-mediated H3K9me3 formation at the pericentromere is not well characterized. To address this question, we introduced HP1 binding-defective, N-terminally truncated mouse Suv39h1 (ΔN) into Suv39h-deficient cells. Pericentric H3K9me3-positive cells were not detected by endogenous-level expression of ΔN. Notably, ΔN could induce pericentric accumulation of H3K9me3 as wild type Suv39h1 did if it was overexpressed. These findings demonstrate that the N-terminal region of Suv39h1, presumably via HP1–Suv39h1 interaction, is required for Suv39h1-mediated pericentric H3K9me3 formation, but can be overridden if Suv39h1 is overproduced, indicating that Suv39h1-mediated heterochromatin formation is controlled by multiple modules, including HP1.