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91.
Akimoto C Kitagawa H Matsumoto T Kato S 《Genes to cells : devoted to molecular & cellular mechanisms》2008,13(6):623-633
The status of chromatin during spermatogenesis is dynamically regulated by specific histone codes or stage-specific histone changes. The functional links between such epigenetic regulation and proteins regulating meiosis are largely unknown. In mammals, genes encoded on the Y chromosome are thought to possess male-specific biological functions. While genes located within the azoospermia factor region (AZF) are known to be involved in spermatogenesis, the physiological function of individual genes is not known. SMCY is a gene mapped to the AZF, and in this report, we analyzed the function of SMCY protein during spermatogenesis. Biochemical identification of the proteins with which it interacted showed that SMCY formed a distinct complex with MSH5, a critical meiosis-regulatory protein in the human testicular germ cell line, NEC8. As anticipated, histone H3K4 demethylase activity was detected. Immunohistochemical analysis revealed the co-localization of SMCY with MSH5 at a specific stage of meiotic prophase progression during murine spermatogenesis. Our results suggest that SMCY may have a male-specific function as a histone H3K4 demethylase by recruiting a meiosis-regulatory protein to condensed DNA. 相似文献
92.
93.
This study examined how different weighting coefficients imposed on individual finger force regulate bimanual finger force coordination patterns under the influence of bilateral coupling and visual information of the force output. The weighted sum of the two forces was computed as the total force output to match two target force levels (10% and 35% MVC) in separate conditions, and visual feedback of the total force output was provided in the experiment. The results revealed higher performance error at 35% in comparison with 10% MVC with the greatest error at the unequal coefficient setting. The correlation between the individual forces and the force output ratios correlated nonlinearly with the weighting coefficient ratios; however, the extent of change was much smaller than the coefficient ratios. The results suggest that bilateral coupling and task constraints interact to determine the coordination strategy. The irregularity of the individual finger forces increased with the weighting coefficient while the irregularity of the total force remained the same. The results support the hypothesis that the organization of redundant motor coordination patterns emerges from the interactive effect of the constraints on movement. 相似文献
94.
Mori N Krensky AM Geleziunas R Wada A Hirayama T Sasakawa C Yamamoto N 《Infection and immunity》2003,71(7):3748-3756
95.
Shinji Watanabe Takahisa Gono Kumiko Nishina Naohiro Sugitani Eri Watanabe Hiroki Yabe Chihiro Terai 《BMC immunology》2017,18(1):53
Background
Some patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) also have positivity of rheumatoid factor (RF). However, the clinical significance of this occurrence remains unknown in AAV patients. The aim of this study was to clarify an association between the presence of RF and clinical features in patients with AAV.Results
Forty-seven patients diagnosed with AAV who were not complicated with RA were enrolled in this study. We compared clinical manifestations of AAV between an RF-positive subset (n?=?29) and an RF-negative subset (n?=?18). The Birmingham Vasculitis Activity Score (BVAS) was higher (P?=?0.026) in the RF-positive subset than in the RF-negative subset. The levels of CRP and ESR were higher in the RF-positive patients (P?=?0.020 and P?=?0.007, respectively) compared to the RF-negative subset. IgM-RF titers were significantly correlated with the BVAS (r?=?0.50, P?=?0.0004). In addition, the IgM-RF titers had significant correlations with the levels of CRP (r?=?0.41, P?=?0.004), ESR (r?=?0.39, P?=?0.016), IgM (r?=?0.36, P?=?0.016) and IgG (r?=?0.37, P?=?0.015). The frequency of commencement of dialysis therapy, usage of mechanical ventilation and mortality were higher in the RF-positive subset than in the RF-negative subset.Conclusions
In patients with AAV, RF titers were significantly correlated with disease activity and the levels of inflammatory markers. The presence of RF could be a poor prognostic factor in patients with AAV.96.
Zhang H Lee EG Liao M Compaore MK Zhang G Kawase O Fujisaki K Sugimoto C Nishikawa Y Xuan X 《Molecular and biochemical parasitology》2007,153(2):141-148
The characterization of the cross-reactive antigens of two closely related apicomplexan parasites, Neospora caninum and Toxoplasma gondii, is important to elucidate the common mechanisms of parasite-host interactions. In this context, a gene encoding N. caninum ribosomal phosphoprotein P0 (NcP0) was identified by immunoscreening of a N. caninum tachyzoite cDNA expression library with antisera from mice immunized with T. gondii tachyzoites. The NcP0 was encoded by a gene with open reading frame of 936 bp, which encoded a protein of 311 amino acids. The NcP0 gene existed as a single copy in the genome and was interrupted by a 432 bp intron. The NcP0 showed 94.5% amino acid identity to T. gondii P0 (TgP0). Anti-recombinant NcP0 (rNcP0) sera recognized a native parasite protein with a molecular mass of 34 kDa in Western blot analysis. Immunofluorescence analysis showed that the NcP0 was localized to the surface of N. caninum tachyzoites. A purified anti-rNcP0 IgG antibody inhibited the growth of N. caninum and T. gondii in vitro in a concentration-dependent manner. These results indicate that P0 is a cross-reactive antigen between N. caninum and T. gondii and a potential common vaccine candidate to control both parasites. 相似文献
97.
Yoshihiro Okamoto Mayuri Tanaka Nobuhiro Miyahara Mie Tanabe Yoshimitsu Gotoh Takuhito Nagai Naoya Fujita Takashi Fukui Toshiyuki Masuzawa 《Journal of clinical laboratory analysis》2009,23(3):175-178
The levels of several soluble cytokine receptors in body fluids of healthy individuals change with age. Clinical application of the measurement of the serum soluble interleukin‐1 receptor type I (sIL‐1RI) level depends critically on the samples used as the controls. At present, there is no information regarding the levels of serum sIL‐1RI in healthy subjects. The purpose of this study is to reveal the age‐related changes that occur in the serum sIL‐1RIlevels of healthy individuals. We determined the serum sIL‐1RI levels of healthy Japanese children using ELISA. The serum sIL‐1RI level of children (0–14 years) was significantly higher than that of adults (more than 15 years) (P=0.0138, n=90). Thus, it is recommended that when the serum sIL‐1RI level of patients is evaluated, it should be compared against age‐matched controls. J. Clin. Lab. Anal. 23:175–178, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
98.
Hyo Jung Kim Jin-Yong Hwang Hyun Jun Kim Wan Sung Choi Jae Heun Lee Hye Jung Kim Ki Churl Chang Toru Nishinaka Chihiro Yabe-Nishimura Han Geuk Seo 《Clinical cancer research》2007,13(9):2577-2583
PURPOSE: The activation of peroxisome proliferator-activated receptor gamma (PPAR gamma) has been implicated in the inhibition of tumor progression in lung cancers through the induction of differentiation and apoptosis. Recently, we identified a novel splice variant of human PPAR gamma1 (hPPAR gamma1) that exhibits dominant-negative activity in human tumor-derived cell lines. This study aimed to examine the expression and pathophysiologic roles of a truncated splice variant of hPPAR gamma1 (hPPAR gamma1(tr)) in primary human lung cancer tissues. EXPERIMENTAL DESIGN: The expression and localization of hPPAR gamma1(tr) was surveyed in human primary lung cancer tissues using immunohistochemistry and Western blot analysis. Using transfectants stably expressing wild-type hPPAR gamma1 (hPPAR gamma1(wt)) and hPPAR gamma1(tr), we also analyzed the pathophysiologic roles of hPPAR gamma1(tr). RESULTS: We showed that PPAR gamma is expressed predominantly in the nucleus of nontumorous tissues, whereas it is present in both the nucleus and the cytoplasm of tumorous tissues in squamous cell carcinoma (SCC) of the lung. Western blot analysis confirmed the presence of PPAR gamma1(tr) in primary lung SCC tissue but not in nontumorous tissue. Expression of PPAR gamma1(tr) in Chinese hamster ovary cells attenuated their susceptibility to cell death induced by oxidative stress or cisplatin, whereas their susceptibility was completely recovered by down-regulation of PPAR gamma1(tr) with small interfering RNA. CONCLUSIONS: hPPAR gamma1(tr) is expressed strongly in tumorous tissues of primary human lung SCC and its overexpression renders transfected cells more resistant to chemotherapeutic drug- and chemical-induced cell death. These data suggest that the decreased drug sensitivity of PPAR gamma1(tr)-expressing cells may be associated with increased tumor aggressiveness and poor clinical prognosis of patients. 相似文献
99.
Naoki Nishida M.D. Tatsuya Takemoto M.D. Chihiro Yamamoto M.D. Tateo Sugimoto M.D. Masaharu Kuge M.D. 《Pediatrics international》1991,33(6):714-717
Caroli's disease is a rare congenital anomaly of the liver. Since new diagnostic techniques for the evaluation of hepatic disease have been introduced, the number of reported cases of Caroli's disease has been gradually increasing. This report describes the case of a 13 year old girl with nausea, vomiting, fever and hepatomegaly. The diagnosis of Caroli's disease was established by ultrasonography and CT scan. The complications and management are discussed. The important points in management are to relieve symptoms and to conduct regular examinations by ultrasonography for the early detection of hepatobiliary carcinoma. 相似文献
100.
Akira Yoshida Tarou Asaga Chihiro Masuzawa Satoru Kawahara Shunsuke Yanoma Masaoki Harada Takasi Okamoto 《Journal of surgical oncology》1994,55(2):104-107
Five cell lines were established from four undifferentiated carcinomas and one squamous cell carcinoma of the thyroid. The levels of several kinds of cytokines were measured in the conditioned media of these cell lines by enzyme-linked immunosorbent assay (ELISA). Interleukin-6 (IL-6) was produced by four of the five cell lines, interleukin-1α (IL-lα) by three cell lines, and granulocyte-colony stimulating factor (G-CSF) by two cell lines. The mRNA of IL-lα or IL-6 was detected by Northern blot analysis in all the cell lines which secreted these cytokines into culture medium. These results suggest that undifferentiated carcinoma and squamous cell carcinoma of the thyroid frequently produce cytokines. Further studies are needed to clarify the possible clinical effects of these cytokines in patients with thyroid carcinoma. © Wiley-Liss, Inc. 相似文献