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121.
122.
Sakiyama Tomoki Morimoto Junko Matsubayashi Jun Furukawa Yasuto Kondo Mami Tsuruga Hifumi Mano Tsutomu Nakamura Futoshi 《Landscape and Ecological Engineering》2021,17(3):351-362
Landscape and Ecological Engineering - Investigating factors underlying human-wildlife conflicts in agricultural landscapes is important for both preventing crop damage and wildlife conservation.... 相似文献
123.
Arakawa Tsutomu Tokunaga Masao Kita Yoshiko Niikura Takako Baker Richard W. Reimer Janice M. Leschziner Andres E. 《The protein journal》2021,40(6):867-875
The Protein Journal - Difference circular dichroism (CD) spectroscopy was used here to characterize changes in structure of flexible peptides upon altering their environments. Environmental changes... 相似文献
124.
Takahashi Yumiko Sarkar Juli Yamada Jumpei Matsunaga Yutaka Nonaka Yudai Banjo Mai Sakaguchi Ryo Shinya Terunaga Hatta Hideo 《Journal of physiology and biochemistry》2021,77(3):469-480
Journal of Physiology and Biochemistry - To identify factors that influence post-exercise muscle glycogen repletion, we compared the glycogen recovery after level running with downhill running, an... 相似文献
125.
Phylogeography of Fischer’s blue,Tongeia fischeri,in Japan: Evidence for introgressive hybridization
Ekgachai Jeratthitikul Takehiro Hara Masaya Yago Tateo Itoh Min Wang Shin-ichi Usami Tsutomu Hikida 《Molecular phylogenetics and evolution》2013,66(1):316-326
The widespread lycaenid butterfly Tongeia fischeri is distributed from eastern Europe to northeastern Asia and represented by three geographically isolated populations in Japan. In order to clarify the phylogeographic history of the species, we used sequences of three mitochondrial (COI, Cyt b and ND5) and two nuclear (Rpl5 and Ldh) genes of 207 individuals collected from 55 sites throughout Japan and five sites on the Asian continent. Phylogenetic trees and the median-joining network revealed six evolutionary mitochondrial haplotype clades, which corresponded to the geographic distribution of the species. Common ancestors of Japanese T. fischeri might have come to Japan during the mid-Pleistocene by multiple dispersals of continental populations, probably via a land bridge or narrow channel between western Japan and the Korean Peninsula. The geographical patterns of variation of mitochondrial and nuclear markers are discordant in northeastern Kyushu, possibly as a result of introgressive hybridization during the ancient contact between the Kyushu and Shikoku populations in the last glacial maximum. The phylogeographic pattern of T. fischeri in Japan are probably related to the geological history, Pleistocene climatic oscillations and distribution of the host plant. 相似文献
126.
Hiroto Ueba Masashi Shiomi Michael Brines Michael Yamin Tsutomu Kobayashi Junya Ako Shin-ichi Momomura Anthony Cerami Masanobu Kawakami 《Molecular medicine (Cambridge, Mass.)》2013,19(1):195-202
Erythropoietin (EPO), a type I cytokine originally identified for its critical role in hematopoiesis, has been shown to have nonhematopoietic, tissue-protective effects, including suppression of atherosclerosis. However, prothrombotic effects of EPO hinder its potential clinical use in nonanemic patients. In the present study, we investigated the antiatherosclerotic effects of helix B surface peptide (HBSP), a nonerythropoietic, tissue-protective compound derived from EPO, by using human umbilical vein endothelial cells (HUVECs) and human monocytic THP-1 cells in vitro and Watanabe heritable hyperlipidemic spontaneous myocardial infarction (WHHLMI) rabbits in vivo. In HUVECs, HBSP inhibited apoptosis (≈70%) induced by C-reactive protein (CRP), a direct mediator of atherosclerosis. By using a small interfering RNA approach, Akt was shown to be a key molecule in HBSP-mediated prevention of apoptosis. HBSP also attenuated CRP-induced production of tumor necrosis factor (TNF)-α and matrix metalloproteinase-9 in THP-1 cells. In the WHHLMI rabbit, HBSP significantly suppressed progression of coronary atherosclerotic lesions as assessed by mean cross-sectional stenosis (HBSP 21.3 ± 2.2% versus control peptide 38.0 ± 2.7%) and inhibited coronary artery endothelial cell apoptosis with increased activation of Akt. Furthermore, TNF-α expression and the number of M1 macrophages and M1/M2 macrophage ratio in coronary atherosclerotic lesions were markedly reduced in HBSP-treated animals. In conclusion, these data demonstrate that HBSP suppresses coronary atherosclerosis, in part by inhibiting endothelial cell apoptosis through activation of Akt and in association with decreased TNF-α production and modified macrophage polarization in coronary atherosclerotic lesions. Because HBSP does not have the prothrombotic effects of EPO, our study may provide a novel therapeutic strategy that prevents progression of coronary artery disease. 相似文献
127.
Takeshi Ishii Tomoe Yamada Taiki Mori Shigenori Kumazawa Koji Uchida Tsutomu Nakayama 《Free radical research》2013,47(11):1253-1260
Lipid peroxidation products contribute to protein aggregation that occurs during oxidative stress in a number of degenerative disorders. Acrolein (ACR), a highly toxic lipid peroxidation aldehyde, is a strong cross-linking agent of cellular components such as proteins. To understand the mechanisms of oxidative stress-induced protein aggregation, this study characterized the ACR modification of chain B from bovine insulin by mass spectrometry. To identify the cross-linking sites, the ACR-treated peptide was digested with a protease and the resulting peptides were analysed by liquid chromatography-tandem mass spectrometry. Inter- and intra-molecular cross-linking adducts were identified between amino groups and the side chain of histidine in the peptide. These results indicated that the ACR-induced cross-links were accompanied by two reactions, namely Michael addition and Schiff base formation. In conclusion, the use of mass spectrometric techniques provided chemical evidence for protein cross-linking with ACR. 相似文献
128.
Isao Kaneko Makoto Iyama-Kadono Kana Togashi-Nishigata Isamu Yamaguchi Tohru Teraoka Tsutomu Arie 《Mycoscience》2013,54(2):148-157
Heterotrimeric GTP-binding proteins (G proteins) and mitogen-activated protein kinase (MAPK) cascades involve vegetative hyphal growth, development of infection-related structure, colonization in host plant and female fertility in phytopathogenic ascomycete fungi. In this study, a heterotrimeric G protein β subunit (Gβ), GPB1, and MAPK, MPK1, were characterized from Fusarium sacchari (= Gibberella sacchari; mating population B of the G. fujikuroi-species complex). GPB1 and MPK1 showed high homology to known Gβ and Fus3/Kss1 MAP kinases of other filamentous ascomycetes, respectively. Disruption (Δ) of gpb1 suppressed hyphal branching and accelerated aerial hyphae formation in F. sacchari. Oppositely, disruption of mpk1 caused delayed aerial hyphae formation. These indicated that GPB1 regulates vegetative hyphal growth negatively, and MPK1 does positively in F. sacchari. Both Δgpb1 and Δmpk1 showed female sterility. Level of intracellular cAMP in Δgpb1 was lower than wild type. Exogenous cyclic AMP (cAMP) partially restored enhanced aerial hyphae formation. These suggested that abnormal hyphal growth was caused by depletion of intracellular cAMP in Δgpb1. cAMP has been reported to suppress development of perithecia in crossing between wild type strains. Thus, precise regulation of intracellular cAMP level via Gβ/MAPK is essential for normal hyphal growth and fertility. 相似文献
129.
Yumiko Kirihara Mayumi Takechi Kaoru Kurosaki Yuta Kobayashi Tsutomu Kurosawa 《Experimental Animals》2013,62(3):173-180
The combination of ketamine and xylazine is a widely used anesthetic for laboratory
animals. However, due to an abuse problem in Japan, ketamine has been specified as a
narcotic since 2007. Instead of using ketamine, Kawai et al. reported an
injectable formula with an equivalent effect to the mixture of ketamine and xylazine
[11]. The mixture of 0.3 mg/kg body weight (b.w.)
medetomidine (Med.), 4.0 mg/kg b.w. midazoram (Mid.), and 5.0 mg/kg b.w. butorphanol
(But.) produced an anesthetic duration of around 40 min in outbred ICR mice. However, the
anesthetic effect of the mixture for inbred mice strains remains unknown. Therefore, we
examined anesthetic effects of the mixture of Med., Mid., and But. in the BALB/c and
C57BL/6J strains. After intraperitoneal injection into mice, right front paw, left hind
paw, and tail pinch reflexes as well as corneal and righting reflexes were observed. Every
5 min, we scored each reflex category as 0 for reaction or 1 for no reaction. As long as
the total score was at least 4 out of 5, we considered the mixture as putting a mouse in a
surgical anesthetic state. The mixture produced an anesthetic duration of more than 45 min
in both strains of mice. These results indicate that the mixture of Med., Mid., and But.
can be a useful and effective anesthesia for the BALB/c and C57BL/6J strains of inbred
mice as well as outbred ICR mice. 相似文献
130.
Tsutomu Shimura Yasushi Ochiai Naoto Noma Toshiyuki Oikawa Yui Sano Manabu Fukumoto 《Cell cycle (Georgetown, Tex.)》2013,12(5):773-782
Fractionated radiotherapy (RT) is widely used in cancer treatment, because it preserves normal tissues. However, repopulation of radioresistant tumors during fractionated RT limits the efficacy of RT. We recently demonstrated that a moderate level of long-term fractionated radiation confers acquired radioresistance to tumor cells, which is caused by DNA-PK/AKT/GSK3β-mediated cyclin D1 overexpression. The resulting cyclin D1 overexpression leads to forced progression of the cell cycle to S-phase, concomitant with induction of DNA double-strand breaks (DSBs). In this study, we investigated the molecular mechanisms underlying cyclin D1 overexpression-induced DSBs during DNA replication in acquired radioresistant cells. DNA fiber data demonstrated that replication forks progressed slowly in acquired radioresistant cells compared with corresponding parental cells in HepG2 and HeLa cell lines. Slowly progressing replication forks were also observed in HepG2 and HeLa cells that overexpressed a nondegradable cyclin D1 mutant. We also found that knockdown of Mus81endonuclease, which is responsible for resolving aberrant replication forks, suppressed DSB formation in acquired radioresistant cells. Consequently, Mus81 created DSBs to remove aberrant replication forks in response to replication perturbation triggered by cyclin D1 overexpression. After treating cells with a specific inhibitor for DNA-PK or ATM, apoptosis rates increased in acquired radioresistant cells but not in parental cells by inhibiting the DNA damage response to cyclin D1-mediated DSBs. This suggested that these inhibitors might eradicate acquired radioresistant cells and improve fractionated RT outcomes. 相似文献