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Kume Manabu Nakayama Naoki Iwasaki Yasunari Hori Tomoya Watanabe Shun Terashima Yuki Medo Ayano Arai Nobuaki Yamashita Yoh Mitamura Hiromichi 《Environmental Biology of Fishes》2021,104(4):529-533
Environmental Biology of Fishes - Eel movement patterns have been frequently studied to learn about their movements within the fresh- and brackish waters of the same river before their spawning... 相似文献
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Maung Maung Theint San Thwe Thidalay Myat Myat Zaw Khin Shimada Tomofumi Bawm Saw Kobayashi Motoko Saing Khin Maung Katakura Ken Arai Satoru Suzuki Hitoshi 《Journal of Mammalian Evolution》2021,28(2):497-509
Journal of Mammalian Evolution - We addressed the spatiotemporal characteristics of four commensal rodent species occurring in Myanmar in comparison with other areas of the Indo-Malayan region. We... 相似文献
105.
Sam-Geun Kong Yoshiyuki Arai Noriyuki Suetsugu Toshio Yanagida Masamitsu Wada 《The Plant cell》2013,25(2):572-590
Phototropins (phot1 and phot2 in Arabidopsis thaliana) relay blue light intensity information to the chloroplasts, which move toward weak light (the accumulation response) and away from strong light (the avoidance response). Chloroplast-actin (cp-actin) filaments are vital for mediating these chloroplast photorelocation movements. In this report, we examine in detail the cp-actin filament dynamics by which the chloroplast avoidance response is regulated. Although stochastic dynamics of cortical actin fragments are observed on the chloroplasts, the basic mechanisms underlying the disappearance (including severing and turnover) of the cp-actin filaments are regulated differently from those of cortical actin filaments. phot2 plays a pivotal role in the strong blue light–induced severing and random motility of cp-actin filaments, processes that are therefore essential for asymmetric cp-actin formation for the avoidance response. In addition, phot2 functions in the bundling of cp-actin filaments that is induced by dark incubation. By contrast, the function of phot1 is dispensable for these responses. Our findings suggest that phot2 is the primary photoreceptor involved in the rapid reorganization of cp-actin filaments that allows chloroplasts to change direction rapidly and control the velocity of the avoidance movement according to the light’s intensity and position. 相似文献
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Toru Karimata Daisuke Sato Daiki Seya Daichi Sato Takashi Wakatsuki Zhonggang Feng Atsuyosi Nishina Masataka Kusunoki Takao Nakamura 《In vitro cellular & developmental biology. Animal》2013,49(10):798-804
Reconstructed myocardial tissue still does not have enough pulsatile contraction. It is well known that fetal and mature neonatal cardiomyocytes utilize glucose and lipid, respectively, as their energy substrates, and that cultured ones mainly use glucose in spite of their age comparable to neonate ones, probably due to insufficient supply of lipids from culture medium. In the present study, we compared 7 saturated, 6 monounsaturated, and 11 polyunsaturated fatty acid contents in cultured cardiomyocytes (Cul group) with those in fetal (Fet group, approximately 17 d after impregnation) and neonatal (Neo group, 9 d old) rats, where the age of the Cul cells were set nearly equal to the Neo ones. Saturated fatty acid contents in the Cul group were generally lower than those in the Fet group and were close to those in the Neo group, except for C12:0 of which content was highest in the Neo group. Monounsaturated fatty acid contents in the Cul group were generally lower than those in the Fet group but similar to or higher than those in the Neo group, except for C24:1n-9 of which content was again highest in the Neo group. In contrast, most of polyunsaturated fatty acid (PUFA) contents in the Cul group appeared lower than those in both the Fet and Neo groups, and differences in 5 of 10 detected PUFAs were significant between the Cul and Neo groups. The results suggest that PUFA contents in cultured cardiomyocytes might be insufficient to exert enough contractile ability. In conclusion, it could be necessary for cultured cardiomyocytes to uptake more lipid; PUFAs in particular. 相似文献
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Daichi Fushihara Hayato Fukuda Hiroshi Abe 《Nucleosides, nucleotides & nucleic acids》2013,32(12):921-941
AbstractDue to the unique rigid and small steric feature of cyclopropane, cyclopropane nucleosides (CPNs) in which the ribose (deoxyribose) of nucleosides are replaced by a hydroxy-substituted cyclopropane, are of great biological interest. Novel 1,1,2-trisubstituted cyclopropane nucleosides were synthesized in enantiomerically pure forms as potential antiviral agents. In the synthesis, two cyclopropane tosylates, which were prepared from chiral cyclopropane lactones previously reported by us, were used effectively as common intermediates for the CPNs. These CPNs are also potentially useful as nucleoside units to incorporate into oligonucleotides in nucleic acids chemotherapy studies. 相似文献
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Hiroshi Shiragami Yusuke Amino Yutaka Honda Masayuki Arai Yasuhiro Tanaka Hisao Iwagami 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):31-45
Abstract Practical method to produce 2′,3′-dideoxypurinenucleosides from 9-(2,5-di-O-acetyl-3-bromo-3-deoxy-β-D-xylofuranosyl)purines (1) was developed. High ratio of 2′,3′-dideoxynucleoside to 3′-deoxyribonucleoside was obtained by selecting the reaction conditions (solvent, pH and/or base), or changing 2′-acyloxy leaving group. The reaction mechanism was studied by deuteration experiments of 1a and 1-(3,5-di-O-acety1-2-bromo-2-deoxy-β-D-ribofuranosyl)thymine (12). 相似文献
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Yoshikazu Arai Jun Ohgane Shuh‐hei Fujishiro Kazuaki Nakano Hitomi Matsunari Masahito Watanabe Kazuhiro Umeyama Dai Azuma Naomi Uchida Nozomu Sakamoto Tomohiro Makino Shintaro Yagi Kunio Shiota Yutaka Hanazono Hiroshi Nagashima 《Genesis (New York, N.Y. : 2000)》2013,51(11):763-776
Porcine induced pluripotent stem cells (iPSCs) provide useful information for translational research. The quality of iPSCs can be assessed by their ability to differentiate into various cell types after chimera formation. However, analysis of chimera formation in pigs is a labor‐intensive and costly process, necessitating a simple evaluation method for porcine iPSCs. Our previous study identified mouse embryonic stem cell (ESC)‐specific hypomethylated loci (EShypo‐T‐DMRs), and, in this study, 36 genes selected from these were used to evaluate porcine iPSC lines. Based on the methylation profiles of the 36 genes, the iPSC line, Porco Rosso‐4, was found closest to mouse pluripotent stem cells among 5 porcine iPSCs. Moreover, Porco Rosso‐4 more efficiently contributed to the inner cell mass (ICM) of blastocysts than the iPSC line showing the lowest reprogramming of the 36 genes (Porco Rosso‐622‐14), indicating that the DNA methylation profile correlates with efficiency of ICM contribution. Furthermore, factors known to enhance iPSC quality (serum‐free medium with PD0325901 and CHIR99021) improved the methylation status at the 36 genes. Thus, the DNA methylation profile of these 36 genes is a viable index for evaluation of porcine iPSCs. genesis 51:763–776. © 2013 Wiley Periodicals, Inc. 相似文献
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