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991.
Hirata Y Hosaka T Iwata T Le CT Jambaldorj B Teshigawara K Harada N Sakaue H Sakai T Yoshimoto K Nakaya Y 《Biochemical and biophysical research communications》2011,(1):96-101
Cysteine-rich protein 2 (CRP2) is a cofactor for smooth muscle cell (SMC) differentiation. Here, we examined the mechanism of CRP2 distribution dynamics during SMC differentiation. CRP2 protein directly associated with F-actin through its N-terminal LIM domain and Gly-rich region, as determined by ELISA. In undifferentiated cells that contain few actin stress fibers, CRP2 was broadly distributed throughout the whole cell, including the nucleus. After induction of SMC differentiation, CRP2 localized to actin stress fibers as they formed. The stress fiber-localized CRP2 entered the nucleus because of induced actin depolymerization. These CRP2 dynamics were reproduced by in silico simulation. CRP2 localization dynamics, which affect CRP2 function, are regulated by the formation of actin stress fibers in conjunction with SMC differentiation. 相似文献
992.
993.
Shouhei Ueda Takatoshi Nakatani Masashi Fukumoto Kiyoshi Maruyama Tateo Itoh Shin‐ichi Usami 《Entomological Science》2020,23(2):216-226
The silver‐studded blue, Plebejus subsolanus, is widely distributed in the Russian Altai mountains, northeastern China, the Korean Peninsula, and the Japanese archipelago. In Japan, the species is distributed across wide elevation ranges from the lowlands of Hokkaido to the subalpine zone of Honshu. Current subspecies classification in Japan is as follows: ssp. iburiensis, occurring in lowland grasslands in Hokkaido; ssp. yaginus in lower mountain grasslands in Honshu; and ssp. yarigadakeanus in higher mountain grasslands in Honshu. The habitat of this species has been markedly reduced due to recent habitat destruction and land‐use changes. Here, we undertook phylogeographic analyses of two subspecies, ssp. yaginus and yarigadakeanus in the central mountainous regions of Japan, based on two mitochondrial gene sequences, in order to collect information for establishing effective conservation strategies. From 57 samples from the four mountain ranges, we obtained a haplotype network comprised of 12 haplotypes. Because of the haplotype network topology, the geographic distribution of haplotypes and the correspondence of haplotype divergence to subspecies taxonomy, we provisionally divided the haplotypes into three haplogroups: YR1 and YR2, which comprised ssp. yarigadakeanus, and YG, which comprised ssp. yaginus. Mitochondrial DNA genetic differentiation generally agreed with morphological subspecies classification. The haplotype network suggested that ssp. yarigadakeanus populations had multiple origins, and the subspecies character of “bright blue of the male's wings” was assumed to have evolved independently in each subalpine meadow. We found that P. subsolanus was genetically differentiated depending upon the elevation at each mountain region, suggesting that each haplogroup should be a conservation unit. 相似文献
994.
Manami Honda Yuki Kuwano Sakurako Katsuura-Kamano Yoshiko Kamezaki Kinuyo Fujita Yoko Akaike Shizuka Kano Kensei Nishida Kiyoshi Masuda Kazuhito Rokutan 《PloS one》2013,8(10)
MicroRNAs (miRNAs) play key roles in regulation of cellular processes in response to changes in environment. In this study, we examined alterations in miRNA profiles in peripheral blood from 25 male medical students two months and two days before the National Examination for Medical Practitioners. Blood obtained one month after the examination were used as baseline controls. Levels of seven miRNAs (miR-16, -20b, -26b, -29a, -126, -144 and -144*) were significantly elevated during the pre-examination period in association with significant down-regulation of their target mRNAs (WNT4, CCM2, MAK, and FGFR1 mRNAs) two days before the examination. State anxiety assessed two months before the examination was positively and negatively correlated with miR-16 and its target WNT4 mRNA levels, respectively. Fold changes in miR-16 levels from two days before to one month after the examination were inversely correlated with those in WNT4 mRNA levels over the same time points. We also confirmed the interaction between miR-16 and WNT4 3′UTR in HEK293T cells overexpressing FLAG-tagged WNT4 3′UTR and miR-16. Thus, a distinct group of miRNAs in periheral blood may participate in the integrated response to chronic academic stress in healthy young men. 相似文献
995.
996.
Mai Wakabayashi Takayasu Mori Kiyoshi Isobe Eisei Sohara Koichiro Susa Yuya Araki Motoko Chiga Eriko Kikuchi Naohiro Nomura Yutaro Mori Hiroshi Matsuo Tomohiro Murata Shinsuke Nomura Takako Asano Hiroyuki Kawaguchi Shigeaki Nonoyama Tatemitsu Rai Sei Sasaki Shinichi Uchida 《Cell reports》2013,3(3):858-868
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997.
The purpose of the research reported here was to elucidate the mechanism of formation of the various lobes observed in asthmatic airways by both theoretical and experimental analysis employing an in vitro airway model. The rationale is that the elucidated mechanism will facilitate the development of new diagnostic methods and treatment regimens for asthma. Lobe formation was analyzed on the basis of an assumption of cross-sectional buckling of the airway. Here, we propose a dynamic visco-elastic buckling model analysis of the airway for the prediction of circumferential and axial buckling mode numbers. The calculated circumferential buckling mode numbers were in reasonably good agreement with those measured in the dynamic buckling experiment using the in vitro airway model. The calculated axial buckling mode numbers were in qualitative agreement with those observed in the experiment. The non-dimensional parameters related to the remodeling and the consequent pathologies occurring in asthmatic airways were also shown, and the influence of changes in the non-dimensional parameters on the circumferential and axial buckling mode numbers was also calculated. The circumferential and axial buckling mode numbers decreased due to thickening and stiffening of the basement membrane. Thickening of the tissues surrounding the basement membrane and the increase in the mucus secreted in the airway lumen were modeled as an increase in the added mass on the basement membrane. The results of calculation showed that the circumferential and axial buckling mode numbers increased because of the thickening of the surrounding tissues and the increase in mucus secretion. We suggest that it may be possible to diagnose the severity of asthma by using the results of the calculation of the changes in the buckling mode numbers caused by the changes in the strength of the remodeling. The physiological reality of the in vitro airway model reported here is discussed using the non-dimensional parameters. 相似文献
998.
Taira Kobayashi Michinaga Ogawa Takahito Sanada Hitomi Mimuro Minsoo Kim Hiroshi Ashida Reiko Akakura Mitsutaka Yoshida Magdalena Kawalec Jean-Marc Reichhart Tsunehiro Mizushima Chihiro Sasakawa 《Cell host & microbe》2013,13(5):570-583
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999.
Kimihiko Murase Kiyoshi Mori Chikara Yoshimura Kensaku Aihara Yuichi Chihara Masanori Azuma Yuka Harada Yoshiro Toyama Kiminobu Tanizawa Tomohiro Handa Takefumi Hitomi Toru Oga Michiaki Mishima Kazuo Chin 《PloS one》2013,8(1)
Background
Both obstructive sleep apnea (OSA) and a novel lipocalin, neutrophil gelatinase associated lipocalin (Ngal), have been reported to be closely linked with cardiovascular disease and loss of kidney function through chronic inflammation. However, the relationship between OSA and Ngal has never been investigated.Objectives
To evaluate the relationship between Ngal and OSA in clinical practice.Methods
In 102 patients, polysomnography was performed to diagnose OSA and plasma Ngal levels were measured. The correlations between Ngal levels and OSA severity and other clinical variables were evaluated. Of the 46 patients who began treatment with continuous positive airway pressure (CPAP), Ngal levels were reevaluated after three months of treatment in 25 patients.Results
The Ngal level correlated significantly with OSA severity as determined by the apnea hypopnea index (r = 0.24, p = 0.01) and 4% oxygen desaturation index (ODI) (r = 0.26, p = 0.01). Multiple regression analysis showed that the Ngal level was associated with 4%ODI independently of other clinical variables. Compliance was good in 13 of the 25 patients who used CPAP. Although the OSA (4%ODI: 33.1±16.7 to 1.1±1.9/h, p<0.01) had significantly improved in those with good compliance, the Ngal levels were not significantly changed (60.5±18.1 before CPAP vs 64.2±13.9 ng/ml after CPAP, p = 0.27).Conclusions
Plasma Ngal levels were positively associated with the severity of OSA. However, the contribution rate of OSA to systemic Ngal secretion was small and changes in Ngal levels appeared to be influenced largely by other confounding factors. Therefore, it does not seem reasonable to use the Ngal level as a specific biomarker of OSA in clinical practice. 相似文献1000.
The cyanobacterial circadian clock oscillator is composed of three clock proteins—KaiA, KaiB, and KaiC, and interactions among the three Kai proteins generate clock oscillation in vitro. However, the regulation of these interactions remains to be solved. Here, we demonstrated that ATP regulates formation of the KaiB-KaiC complex. In the absence of ATP, KaiC was monomeric (KaiC1mer) and formed a complex with KaiB. The addition of ATP plus Mg2+ (Mg-ATP), but not that of ATP only, to the KaiB-KaiC1mer complex induced the hexamerization of KaiC and the concomitant release of KaiB from the KaiB-KaiC1mer complex, indicating that Mg-ATP and KaiB compete each other for KaiC. In the presence of ATP and Mg2+ (Mg-ATP), KaiC became a homohexameric ATPase (KaiC6mer) with bound Mg-ATP and formed a complex with KaiB, but KaiC hexamerized by unhydrolyzable substrates such as ATP and Mg-ATP analogs, did not. A KaiC N-terminal domain protein, but not its C-terminal one, formed a complex with KaiB, indicating that KaiC associates with KaiB via its N-terminal domain. A mutant KaiC6mer lacking N-terminal ATPase activity did not form a complex with KaiB whereas a mutant lacking C-terminal ATPase activity did. Thus, the N-terminal domain of KaiC is responsible for formation of the KaiB-KaiC complex, and the hydrolysis of the ATP bound to N-terminal ATPase motifs on KaiC6mer is required for formation of the KaiB-KaiC6mer complex. KaiC6mer that had been hexamerized with ADP plus aluminum fluoride, which are considered to mimic ADP-Pi state, formed a complex with KaiB, suggesting that KaiB is able to associate with KaiC6mer with bound ADP-Pi. 相似文献