著者

Koji Kimura Kouichi Hayashi Koji Hagihara Hitoshi Izuno Naohisa Happo Shinya Hosokawa Motohiro Suzuki Hiroo Tajiri

出版者

The Japan Institute of Metals and Materials

雑誌

MATERIALS TRANSACTIONS (ISSN:13459678)

巻号頁・発行日

vol.58, no.4, pp.539-542, 2017-04-01 (Released:2017-03-25)

参考文献数

24

被引用文献数

10 16

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We performed X-ray fluorescence holography measurements on a single crystal Mg85Zn6Y9 alloy, having a synchronized 18R long period stacking ordered structure, and successfully obtained Zn Kα holograms. The reconstruction shows “U”-shaped atomic images in remarkable contrast to the prediction of an existing model with Zn6Y8 L12 clusters. To explain this feature we calculated holograms using a model with positional fluctuations, and fit the reconstruction to the experimental results. It was found that large rotational fluctuations of the clusters can explain the “U”-shaped images.

著者

Shun TAKEO Daichi SATO Koji KIMURA Yasunori MONJI Takehito KUWAYAMA Ryoka KAWAHARA-MIKI Hisataka IWATA

出版者

日本繁殖生物学会

雑誌

Journal of Reproduction and Development (ISSN:09168818)

巻号頁・発行日

vol.60, no.2, pp.92-99, 2014 (Released:2014-04-24)

参考文献数

38

被引用文献数

17 63

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The aim of the present study was to address the effect of resveratrol-mediated upregulation of sirtuin 1 (SIRT1) during oocyte maturation on mitochondrial function, the developmental ability of oocytes and on mechanisms responsible for blockage of polyspermic fertilization. Oocytes collected from slaughterhouse-derived ovaries were cultured in TCM-199 medium supplemented with 10% FCS and 0 or 20 µM resveratrol (Res). We examined the effect of Res on SIRT1 expression in in vitro-matured oocytes (Exp 1); fertilization and developmental ability (Exp 2); mitochondrial DNA copy number (Mt number), ATP content and mitochondrial membrane potential in matured oocytes (Exp 3); and the time required for proteinase to dissolve the zona pellucida following in vitro fertilization (as a marker of zona pellucida hardening), as well as on the distribution of cortical granules before and after fertilization (Exp 4). In Exp 1, the 20 µM Res treatment upregulated protein expression of SIRT1 in oocytes. In Exp 2, Res treatment improved the ratio of normal fertilization and the total cell number of blastocysts. In Exp 3, Res treatment significantly increased the ATP content in matured oocytes. Additionally, Res increased the overall Mt number and mitochondrial membrane potential, but the effect was donor-dependent. In Exp 4, Res-induced zona hardening improved the distribution and exocytosis of cortical granules after in vitro fertilization. In conclusion, Res improved the quality of oocytes by improving mitochondrial quantity and quality. In addition, Res added to the maturation medium enhanced SIRT1 protein expression in oocytes and improved fertilization via reinforcement of the mechanisms responsible for blockage of polyspermic fertilization.