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131.
Shima Okada Naruhiro Shiozawa Yoshihisa Fujiwara Yasushi Yasuda Masaaki Makikawa Takeo Iida 《Journal of thermal biology》2008
To clarify the effect of cold stimulation during slow-wave sleep (SWS) on the sleep cycle, we conducted a sleep experiment. Five healthy males slept on a bedding system we developed to make the inside of bedding cooler. When the subject was sleeping deeply in the second and fourth SWS, the system cooled their bedding. When the subject's sleep condition shifted toward arousal, the cold air was stopped. As a result, all subjects’ sleep stage shifted to light sleep and reached arousal. After stopping stimulation, they immediately returned to the SWS at the first stimulation. But at the second stimulation, the sleep state did not return to the SWS. 相似文献
132.
Self-Cloning Baker's Yeasts That Accumulate Proline Enhance Freeze Tolerance in Doughs 总被引:1,自引:0,他引:1 下载免费PDF全文
Tomohiro Kaino Tetsuya Tateiwa Satomi Mizukami-Murata Jun Shima Hiroshi Takagi 《Applied microbiology》2008,74(18):5845-5849
We constructed self-cloning diploid baker's yeast strains by disrupting PUT1, encoding proline oxidase, and replacing the wild-type PRO1, encoding γ-glutamyl kinase, with a pro1(D154N) or pro1(I150T) allele. The resultant strains accumulated intracellular proline and retained higher-level fermentation abilities in the frozen doughs than the wild-type strain. These results suggest that proline-accumulating baker's yeast is suitable for frozen-dough baking. 相似文献
133.
K Katayama Y Sato Y Morotome N Shima K Ishida S Mori M Miyamura 《Journal of applied physiology》2001,90(4):1431-1440
The purpose of this study was 1) to test the hypothesis that ventilation and arterial oxygen saturation (Sa(O2)) during acute hypoxia may increase during intermittent hypoxia and remain elevated for a week without hypoxic exposure and 2) to clarify whether the changes in ventilation and Sa(O2) during hypoxic exercise are correlated with the change in hypoxic chemosensitivity. Six subjects were exposed to a simulated altitude of 4,500 m altitude for 7 days (1 h/day). Oxygen uptake (VO2), expired minute ventilation (VE), and Sa(O2) were measured during maximal and submaximal exercise at 432 Torr before (Pre), after intermittent hypoxia (Post), and again after a week at sea level (De). Hypoxic ventilatory response (HVR) was also determined. At both Post and De, significant increases from Pre were found in HVR at rest and in ventilatory equivalent for O2 (VE/VO2) and Sa(O2) during submaximal exercise. There were significant correlations among the changes in HVR at rest and in VE/VO2 and Sa(O2) during hypoxic exercise during intermittent hypoxia. We conclude that 1 wk of daily exposure to 1 h of hypoxia significantly improved oxygenation in exercise during subsequent acute hypoxic exposures up to 1 wk after the conditioning, presumably caused by the enhanced hypoxic ventilatory chemosensitivity. 相似文献
134.
Genomic organization and expression of the doublesex-related gene cluster in vertebrates and detection of putative regulatory regions for DMRT1. 总被引:16,自引:0,他引:16
B Brunner U Hornung Z Shan I Nanda M Kondo E Zend-Ajusch T Haaf H H Ropers A Shima M Schmid V M Kalscheuer M Schartl 《Genomics》2001,77(1-2):8-17
Genes related to the Drosophila melanogaster doublesex and Caenorhabditis elegans mab-3 genes are conserved in human. They are identified by a DNA-binding homology motif, the DM domain, and constitute a gene family (DMRTs). Unlike the invertebrate genes, whose role in the sex-determination process is essentially understood, the function of the different vertebrate DMRT genes is not as clear. Evidence has accumulated for the involvement of DMRT1 in male sex determination and differentiation. DMRT2 (known as terra in zebrafish) seems to be a critical factor for somitogenesis. To contribute to a better understanding of the function of this important gene family, we have analyzed DMRT1, DMRT2, and DMRT3 from the genome model organism Fugu rubripes and the medakafish, a complementary model organism for genetics and functional studies. We found conservation of synteny of human chromosome 9 in F. rubripes and an identical gene cluster organization of the DMRTs in both fish. Although expression analysis and gene linkage mapping in medaka exclude a function for any of the three genes in the primary step of male sex determination, comparison of F. rubripes and human sequences uncovered three putative regulatory regions that might have a role in more downstream events of sex determination and human XY sex reversal. 相似文献
135.
Akitoshi Nakashima Mikiko Yamanaka-Tatematsu Naonobu Fujita Keiichi Koizumi Tomoko Shima Toshiko Yoshida Toshio Nikaido Aikou Okamoto Tamotsu Yoshimori Shigeru Saito 《Autophagy》2013,9(3):303-316
In early pregnancy, trophoblasts and the fetus experience hypoxic and low-nutrient conditions; nevertheless, trophoblasts invade the uterine myometrium up to one third of its depth and migrate along the lumina of spiral arterioles, replacing the maternal endothelial lining. Here, we showed that autophagy, an intracellular bulk degradation system, occurred in extravillous trophoblast (EVT) cells under hypoxia in vitro and in vivo. An enhancement of autophagy was observed in EVTs in early placental tissues, which suffer from physiological hypoxia. The invasion and vascular remodeling under hypoxia were significantly reduced in autophagy-deficient EVT cells compared with wild-type EVT cells. Interestingly, soluble endoglin (sENG), which increased in sera in preeclamptic cases, suppressed EVT invasion by inhibiting autophagy. The sENG-inhibited EVT invasion was recovered by TGFB1 treatment in a dose-dependent manner. A high dose of sENG inhibited the vascular construction by EVT cells and human umbilical vein endothelial cells (HUVECs), meanwhile a low dose of sENG inhibited the replacement of HUVECs by EVT cells. A protein selectively degraded by autophagy, SQSTM1, accumulated in EVT cells in preeclamptic placental biopsy samples showing impaired autophagy. This is the first report showing that impaired autophagy in EVT contributes to the pathophysiology of preeclampsia. 相似文献
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138.
The morphological characteristics of the pectoral fin spine were compared in three species of sturgeon, the Persian sturgeon (Acipenser persicus), the Russian sturgeon (Acipenser gueldenstaedtii), and the Starry sturgeon (Acipenser stellatus), all sampled from the Caspian Sea. On the basis of morphological characters of the pectoral fin spine, 62.2% of the individuals were correctly classified into separate groups. The cluster analysis also divided the three species into two major subgroups. Acipenser persicus and A. gueldenstaedtii were grouped together, suggesting a similar evolutionary basis. Significant morphological heterogeneity in pectoral fin spine characteristics was observed among the three sturgeon species. Principal component analysis identified the largest differences were in the pectoral fin spine size and the angle between distal pectoral fin spine and the horizontal line (A°). The first and second principal components (PC1 and PC2) of all observations accounted for 64.19% and 14.33% of the total variation, respectively. The combination of all analyses showed the relevance of applying pectoral fin spine shape for interspecific distinction of the three species of sturgeons. 相似文献
139.
Camille V. Chagneau Clmence Massip Nadge Bossuet-Greif Christophe Fremez Jean-Paul Motta Ayaka Shima Cline Besson Pauline Le Faouder Nicolas Cnac Marie-Paule Roth Hlne Coppin Maxime Fontani Patricia Martin Jean-Philippe Nougayrde Eric Oswald 《PLoS pathogens》2021,17(2)
Urinary tract infections (UTIs) are among the most common outpatient infections, with a lifetime incidence of around 60% in women. We analysed urine samples from 223 patients with community-acquired UTIs and report the presence of the cleavage product released during the synthesis of colibactin, a bacterial genotoxin, in 55 of the samples examined. Uropathogenic Escherichia coli strains isolated from these patients, as well as the archetypal E. coli strain UTI89, were found to produce colibactin. In a murine model of UTI, the machinery producing colibactin was expressed during the early hours of the infection, when intracellular bacterial communities form. We observed extensive DNA damage both in umbrella and bladder progenitor cells. To the best of our knowledge this is the first report of colibactin production in UTIs in humans and its genotoxicity in bladder cells. 相似文献
140.
Measurement of PO2 in liver using EPR oximetry 总被引:1,自引:0,他引:1
Jiang J.; Nakashima T.; Liu K. J.; Goda F.; Shima T.; Swartz H. M. 《Journal of applied physiology》1996,80(2):552-558