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141.
Kajiura-Kobayashi H Yoshida N Sagata N Yamashita M Nagahama Y 《Development genes and evolution》2000,210(8-9):416-425
Mos plays a crucial role in meiotic cell division in vertebrates. In Xenopus, Mos is involved in the initiation of oocyte maturation as an initiator and in the arrest at the metaphase II stage (MII)
as a component of the cytostatic factor (CSF). The function of Mos is mediated by MAP kinase (MAPK). We investigated the function
of the Mos/MAPK pathway during goldfish oocyte maturation induced by 17α,20β-dihydroxy-4-pregnen-3-one (17α,20β-DP), a natural
maturation-inducing hormone in fishes. Mos was absent in immature goldfish oocytes. It appeared before the onset of germinal
vesicle breakdown (GVBD), increased to a maximum in mature oocytes arrested at MII and disappeared after fertilization. MAPK
was activated after Mos synthesis but before maturation-promoting factor (MPF) activation, and its activity reached maximum
at MII. Injection of either Xenopus or goldfish c-mos mRNA into one blastomere of 2-cell-stage Xenopus and goldfish embryos induced metaphase arrest, suggesting that goldfish Mos has a CSF activity. Injection of constitutively
active Xenopus c-mos mRNA into immature goldfish oocytes induced MAPK activation, but neither MPF activation nor GVBD occurred. Conversely, the
injection of goldfish c-mos antisense RNA inhibited both Mos synthesis and MAPK activation in the 17α,20β-DP-treated oocytes, but these oocytes underwent
GVBD. These results indicate that the Mos/MAPK pathway is not essential for initiating goldfish oocyte maturation despite
its general function as a CSF. We discuss the general role of Mos/MAPK during oocyte maturation, with reference to the difference
in contents of inactive MPF (pre-MPF) stored in immature oocytes.
Received: 10 February 2000 / Accepted: 25 April 2000 相似文献
142.
cGMP-dependent protein kinase (cGK) is a major cellular receptor of cGMP and plays important roles in cGMP-dependent signal transduction pathways. To isolate the components of the cGMP/cGK signaling pathway such as substrates and regulatory proteins of cGK, we employed the yeast two-hybrid system using cGK-Ialpha as a bait and isolated a novel male germ cell-specific 42-kDa protein, GKAP42 (42-kDa cGMP-dependent protein kinase anchoring protein). Although the N-terminal region (amino acids 1-66) of cGK-Ialpha is sufficient for the association with GKAP42, GKAP42 could not interact with cGK-Ibeta, cGK-II, or cAMP-dependent protein kinase. GKAP42 mRNA is specifically expressed in testis, where it is restricted to the spermatocytes and early round spermatids. Endogenous cGK-I is co-immunoprecipitated with anti-GKAP42 antibody from mouse testis tissue, suggesting that cGK-I physiologically interacts with GKAP42. Immunocytochemical observations revealed that GKAP42 is localized to the Golgi complex and that cGK-Ialpha is co-localized to the Golgi complex when coexpressed with GKAP42. Although both cGK-Ialpha and -Ibeta, but not cAMP-dependent protein kinase, phosphorylated GKAP42 in vitro, GKAP42 was a good substrate only for cGK-Ialpha in intact cells, suggesting that the association with kinase protein is required for the phosphorylation in vivo. Finally, we demonstrated that the kinase-deficient mutant of cGK-Ialpha stably associates with GKAP42 and that binding of cGMP to cGK-Ialpha facilitates their release from GKAP42. These findings suggest that GKAP42 functions as an anchoring protein for cGK-Ialpha and that cGK-Ialpha may participate in germ cell development through phosphorylation of Golgi-associated proteins such as GKAP42. 相似文献
143.
In malic enzyme-dependent crassulacean-acid-metabolism (ME-CAM) plants, malic acid is decarboxylated by NADP-ME and NAD-ME and generates pyruvate with CO2. Pyruvate is phosphorylated to phosphoenolpyruvate by pyruvate, Pi dikinase (PPDK) and is then conserved in gluconeogenesis. Although PPDK was considered to be located in chloroplasts (e.g., Mesembryanthemum crystallinum), it has recently been found to accumulate in both the chloroplasts and the cytosol in two Kalancho? species. In this study, the intracellular localization of PPDK was investigated in 22 ME-CAM species in 13 genera of 5 families by immunogold labeling and electron microscopy. This revealed that the pattern of intracellular localization of PPDK varies among the ME-CAM plants and is divided into three types: Chlt, in which PPDK accumulates only in the chloroplasts; Cyt-Chlt, in which PPDK accumulates in both chloroplasts and cytosol; and Cyt, in which PPDK accumulates predominantly in the cytosol. Members of a particular genus tend to have a common PPDK-localization type. In the Cactaceae, all species from seven genera were classified as Cyt. The photosynthetic tissues of all ME-CAM species, including the Cyt type, had substantial PPDK activity, suggesting that PPDK in the cytosol is active and probably plays a functional role. In the Chlt species, NADP-ME activity was relatively greater than NAD-ME activity. In the Cyt-Chlt and Cyt species, however, either the activity of NAD-ME was higher than that of NADP-ME or they were approximately the same. The species variation in the intracellular localization of PPDK is discussed in relation to CAM function and to molecular and phylogenetic aspects. 相似文献
144.
Shinrin-yoku (forest-air bathing and walking) effectively decreases blood glucose levels in diabetic patients 总被引:6,自引:0,他引:6
Y. Ohtsuka Noriyuki Yabunaka Shigeru Takayama 《International journal of biometeorology》1998,41(3):125-127
The influence of ”shinrin-yoku” (forest-air bathing and walking) on blood glucose levels in diabetic patients was examined.
Eighty-seven (29 male and 58 female) non-insulin-dependent diabetic patients [61 (SEM 1) years old] participated in the present
study. Shinrin-yoku was performed nine times over a period of 6 years. The patients were divided into two parties. They then
walked in the forest for 3 km or 6 km according to their physical ability and/or the existence of diabetic complications.
The mean blood glucose level after forest walking changed from 179 (SEM 4) mg · 100 ml–1 to 108 (SEM 2) mg · 100 ml–1 (P<0.0001). The level of glycated haemoglobin A1c also decreased from 6.9 (SEM 0.2)% (before the first shinrin-yoku) to 6.5 (SEM 0.1)% (after the last shinrin-yoku; P<0.05). Blood glucose values declined by 74 (SEM 9) mg · 100 ml–1 and 70 (SEM 4) mg · 100 ml–1 after short- and long-distance walking respectively. There was no significant difference between these values. Since the
forest environment causes changes in hormonal secretion and autonomic nervous functions, it is presumed that, in addition
to the increased calorie consumption and improved insulin sensitivity, walking in a forest environment has other beneficial
effects in decreasing blood glucose levels.
Received: 9 July 1997/Accepted: 20 October 1997 相似文献
145.
146.
Ogawa Noriyuki; Yabuta Naohiro; Ueno Yoshihisa; Izui Katsura 《Plant & cell physiology》1998,39(10):1010-1019
Phosphoenolpyruvate carboxylase (PEPC) [EC 4.1.1.31
[EC]
] of plantsundergoes regulatory phosphorylation in response to light ornutritional conditions. However, the nature of protein kinase(s)for this phosphorylation has not yet been fully elucidated.We separated a Ca2+-requiring protein kinase from Ca2+-independentone, both of which can phosphorylate maize leaf PEPC and characterizedthe former kinase after partial purification. Several linesof evidence indicated that the kinase is one of the characteristicCa2+-dependent but calmodulin-independent protein kinase (CDPK).Although the Mr, of native CDPK was estimated to be about 100kDa by gel permeation chromatography, in situ phosphorylationassay of CDPK in a SDS-polyacrylamide gel revealed that thesubunit has an Mr of about 50 kDa suggesting dimer formationor association with other protein(s). Several kinetic parameterswere also obtained using PEPC as a substrate. Although the CDPKshowed an ability of regulatory phosphorylation (Ser-15 in maizePEPC), no significant desensitization to feedback inhibitor,malate, could be observed presumably due to low extent of phosphorylation.The kinase was not specific to PEPC but phosphorylated a varietyof synthetic peptides. The possible physiological role of thiskinase was discussed.
1Present address: NEOS Central Research Laboratory, 1-1 Ohike-machi,Kosei-cho, Shiga, 520-3213 Japan.
2Present address: Chugai Pharmaceutical Co., Ltd., 1-135 Komakado,Gotemba, 412-0038 Japan.
4N.O. and N.Y. contributed equally to this work. 相似文献
147.
Masato Yuasa Tsuyoshi Yamada Takashi Taniyama Tomokazu Masaoka Wei Xuetao Toshitaka Yoshii Masaki Horie Hiroaki Yasuda Toshimasa Uemura Atsushi Okawa Shinichi Sotome 《PloS one》2015,10(2)
We evaluated whether dexamethasone augments the osteogenic capability of bone marrow-derived stromal cells (BMSCs) and muscle tissue-derived stromal cells (MuSCs), both of which are thought to contribute to ectopic bone formation induced by bone morphogenetic protein-2 (BMP-2), and determined the underlying mechanisms. Rat BMSCs and MuSCs were cultured in growth media with or without 10-7 M dexamethasone and then differentiated under osteogenic conditions with dexamethasone and BMP-2. The effects of dexamethasone on cell proliferation and osteogenic differentiation, and also on ectopic bone formation induced by BMP-2, were analyzed. Dexamethasone affected not only the proliferation rate but also the subpopulation composition of BMSCs and MuSCs, and subsequently augmented their osteogenic capacity during osteogenic differentiation. During osteogenic induction by BMP-2, dexamethasone also markedly affected cell proliferation in both BMSCs and MuSCs. In an in vivo ectopic bone formation model, bone formation in muscle-implanted scaffolds containing dexamethasone and BMP-2 was more than two fold higher than that in scaffolds containing BMP-2 alone. Our results suggest that dexamethasone potently enhances the osteogenic capability of BMP-2 and may thus decrease the quantity of BMP-2 required for clinical application, thereby reducing the complications caused by excessive doses of BMP-2.Highlights: 1. Dexamethasone induced selective proliferation of bone marrow- and muscle-derived cells with higher differentiation potential. 2. Dexamethasone enhanced the osteogenic capability of bone marrow- and muscle-derived cells by altering the subpopulation composition. 3. Dexamethasone augmented ectopic bone formation induced by bone morphogenetic protein-2. 相似文献
148.
Ryutaro Kakinuma Noriyuki Moriyama Yukio Muramatsu Shiho Gomi Masahiro Suzuki Hirobumi Nagasawa Masahiko Kusumoto Tomohiko Aso Yoshihisa Muramatsu Takaaki Tsuchida Koji Tsuta Akiko Miyagi Maeshima Naobumi Tochigi Shun-ichi Watanabe Naoki Sugihara Shinsuke Tsukagoshi Yasuo Saito Masahiro Kazama Kazuto Ashizawa Kazuo Awai Osamu Honda Hiroyuki Ishikawa Naoya Koizumi Daisuke Komoto Hiroshi Moriya Seitaro Oda Yasuji Oshiro Masahiro Yanagawa Noriyuki Tomiyama Hisao Asamura 《PloS one》2015,10(12)
149.
Yosuke Hamamoto Hiromu Ito Moritoshi Furu Motomu Hashimoto Takao Fujii Masahiro Ishikawa Noriyuki Yamakawa Chikashi Terao Masayuki Azukizawa Takahiro Iwata Tsuneyo Mimori Shuichi Matsuda 《PloS one》2015,10(8)
Objective
To investigate clinical and radiological differences between joint destruction in the wrist and the feet in patients with RA.Methods
A cross-sectional clinical study was conducted in an RA cohort at a single institution. Clinical data included age, sex and duration of disease. Laboratory data included sero-positivity for anti-cyclic citrullinated peptide (CCP) antibody and RF. Radiological measurements included Larsen grades and the modified Sharp/van der Heijde method (SHS) for the hands/wrists and the feet. Statistical analyses were performed using the Kruskal—Wallis H-test, a dummy variable linear regression model and multivariate logistic regression analysis with 95% confidence interval and odds ratios.Results
A total of 405 patients were enrolled, and 314 patients were analysed in this study. The duration of disease in the foot-dominant group was significantly less than that in the wrist-dominant group. When patients were subdivided by duration of disease, the Larsen grade of the feet was significantly higher than that of the wrist in the first quadrant subgroup, but this was reversed with increasing duration of disease. Anti-CCP status was a significant predictive factor for joint destruction in the wrist but not in the feet, while RF status was not predictive in either the wrist or the feet.Conclusions
Joint destruction in the feet started earlier than in the wrist, but the latter progresses faster with increasing duration of disease. Anti-CCP status predicts joint destruction in the wrist better than in the feet. 相似文献150.
Yuko Amano Noriyuki Kimura Takuya Hanaoka Yasuhiro Aso Teruyuki Hirano Hiroyuki Murai Katsuya Satoh Etsuro Matsubara 《朊病毒》2015,9(1):29-33
ABSTRACT. Here we report a genetically confirmed case of Creutzfeldt-Jakob disease with a prion protein gene codon 180 mutation presenting atypical magnetic resonance imaging findings. The present case exhibited an acute onset and lateralized neurologic signs, and progressive cognitive impairment. No myoclonus or periodic synchronous discharges on electroencephalography were observed. Diffusion-weighted images revealed areas of high signal intensity in the right frontal and temporal cortices at onset that extended to the whole cortex and basal ganglia of the right cerebral hemisphere at 3 months. Although the cerebrospinal fluid (CSF) was initially negative for neuron specific enolase, tau protein, 14–3–3 protein, and abnormal prion protein, the CSF was positive for these brain-derived proteins at 3 months after onset. 相似文献