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871.
Yuichi Yoshimura Hiroshi Satoh Shinji Sakata Noriyuki Ashida Shuichi Miyazaki Akira Matsud 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):427-429
Abstract 2′-C-Cyanomethyl-2′-deoxy-arabinosylcytosine 3 and 2′-C-azidomethyl-2′-deoxy-arabinosylcytosine 4 were synthesized from uridine. The antineoplastic activities of these compounds were evaluated. 相似文献
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873.
Gwendoline Clotuche Anne-Catherine Mailleux Shuichi Yano Claire Detrain Jean-Louis Deneubourg Thierry Hance 《Comptes rendus biologies》2013,336(2):93-101
In silk-spinning arthropods, silk can be used for web building, protection, and communication. Silk is an informative material about the presence of conspecifics. It can therefore inform on habitat suitability and hence assist in habitat choice. In this context, we investigated the influence of silk on microhabitat choice by the two-spotted spider mite, Tetranychus urticae. Three factors that could potentially influence habitat choice were manipulated: the strain, number, and the stage of mites. Our study showed that these factors all influence the choice of microhabitat. The tendency of whether to settle on a silk-covered area was influenced by the origin of mites (strain effect). Adult females showed a higher tendency to settle on an area covered with the silk laid by numerous congeners (number effect). Moreover, larvae seemed to be more responsive to the presence of silk than adults (stage effect). This suggests that individuals use silk as a social cue in selecting their microhabitat and that the spatial organization and group behaviour seem to be shaped by the individuals’ response to social cues, such as the amount of silk already present. 相似文献
874.
Koichi Murata Moritoshi Furu Hiroyuki Yoshitomi Masahiro Ishikawa Hideyuki Shibuya Motomu Hashimoto Yoshitaka Imura Takao Fujii Hiromu Ito Tsuneyo Mimori Shuichi Matsuda 《PloS one》2013,8(7)
MicroRNAs (miRNAs) are present in human plasma and known as a non-invasive biomarker for cancer detection. Our study was designed to identify plasma miRNAs specific for rheumatoid arthritis (RA) by a comprehensive array approach. We performed a systematic, array-based miRNA analysis on plasma samples from three RA patients and three healthy controls (HCs). Plasma miRNAs with more than four times change or with significant (P<0.05) change in expression, or detectable only in RA plasma, were confirmed with plasma from eight RA patients and eight HCs using real-time quantitative PCR. Consistently detectable miRNAs that were significantly different between RA patients and HCs were chosen for further validation with 102 RA patients and 104 HCs. The area under curves (AUC) were calculated after plotting the receiver operating characteristic (ROC) curves. To determine if these miRNAs are specific for RA, the concentrations of these miRNAs were analyzed in 24 patients with osteoarthritis (OA), and 11 patients with systemic lupus erythematosus (SLE). The array analysis and the subsequent confirmation in larger patient cohort identified significant alterations in plasma levels of seven miRNAs. The highest AUC was found for miR-125a-5p, followed in order by miR-24 and miR-26a. Multivariable logistic regression analysis showed that miR-24, miR-30a-5p, and miR-125a-5p were crucial factors for making detection model of RA and provided a formula for Estimated Probability of RA by plasma MiRNA (ePRAM), employing miR-24, miR-30a-5p and miR-125a-5p, which showed increased diagnostic accuracy (AUC: 0.89). The level of miR-24, miR-125a-5p, and ePRAM in OA and SLE patients were lower than that in RA. There was no significant difference in detection for anti-citrullinated protein antibody (ACPA)-positive and ACPA-negative RA patients. These results suggest that the plasma concentrations of miR-24 and miR-125a-5p, and ePRAM are potential diagnostic markers of RA even if patients were ACPA-negative. 相似文献
875.
Hiroshi Nakano Yoko Shibata Sumito Inoue Akira Igarashi Keiko Yamauchi Shuichi Abe Masamichi Sato Yasuko Aida Keiko Nunomiya Tomomi Kimura Takako Nemoto Tetsu Watanabe Tsuneo Konta Yoshiyuki Ueno Takeo Kato Takamasa Kayama Isao Kubota 《PloS one》2013,8(12)
Background
Accumulating evidence suggests the involvement of an autoimmune mechanism in the pathogenesis of respiratory dysfunction. The aim of this study was to investigate the relationship between pulmonary function and serum antibodies to several connective tissue disease autoantigens (ACTDA) levels, which has not been investigated in a general population.Methods
Blood sampling and spirometry were performed for subjects (n = 3,257) aged ≥40 years who participated in a community-based annual health check in Takahata, Japan, from 2004 to 2006. ACTDA was measured by enzyme immunoassay, and subjects with ACTDA values ≥20 were defined as positive.Results
In males, there were significant inverse relationships between logarithmically transformed ACTDA values and spirometric parameters, including % predicted values for forced expiratory volume in 1 s (FEV1) and maximal midexpiratory flow (MMF) as well as FEV1/forced vital capacity (FVC). Multiple linear regression analysis revealed that except for the relationship between ACTDA and FEV1/FVC, these relationships were still significant after adjustment for Brinkman index (a measure of inhaled cigarette consumption). The prevalence of positive ACTDA was greater in male never-smokers with mixed ventilation disorders and relatively severe airflow obstruction (% predicted FEV1 below the median value).Conclusions
Autoimmunity may be involved in the mechanism of impaired pulmonary function in the general population. 相似文献876.
Masaki Miyazaki Hidetoshi Nakamura Shotaro Chubachi Mamoru Sasaki Mizuha Haraguchi Shuichi Yoshida Keishi Tsuduki Toru Shirahata Saeko Takahashi Naoto Minematsu Hidefumi Koh Morio Nakamura Fumio Sakamaki Takeshi Terashima Koichi Sayama Paul W Jones Koichiro Asano Tomoko Betsuyaku 《Respiratory research》2014,15(1):13
Background
The chronic obstructive pulmonary disease (COPD) Assessment Test (CAT) is a concise health status measure for COPD. COPD patients have a variety of comorbidities, but little is known about their impact on quality of life. This study was designed to investigate comorbid factors that may contribute to high CAT scores.Methods
An observational study at Keio University and affiliated hospitals enrolled 336 COPD patients and 67 non-COPD subjects. Health status was assessed by the CAT, the St. Georges Respiratory Questionnaire (SGRQ), and all components of the Medical Outcomes Study Short-Form 36-Item (SF-36) version 2, which is a generic measure of health. Comorbidities were identified based on patients’ reports, physicians’ records, and questionnaires, including the Frequency Scale for the Symptoms of Gastro-esophageal reflux disease (GERD) and the Hospital Anxiety and Depression Scale. Dual X-ray absorptiometry measurements of bone mineral density were performed.Results
The CAT showed moderate-good correlations with the SGRQ and all components of the SF-36. The presence of GERD, depression, arrhythmia, and anxiety was significantly associated with a high CAT score in the COPD patients.Conclusions
Symptomatic COPD patients have a high prevalence of comorbidities. A high CAT score should alert the clinician to a higher likelihood of certain comorbidities such as GERD and depression, because these diseases may co-exist unrecognized.Trial registration
Clinical trial registered with UMIN (UMIN000003470). 相似文献877.
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880.
Fukunaka A Kurokawa Y Teranishi F Sekler I Oda K Ackland ML Faundez V Hiromura M Masuda S Nagao M Enomoto S Kambe T 《The Journal of biological chemistry》2011,286(18):16363-16373
A number of enzymes become functional by binding to zinc during their journey through the early secretory pathway. The zinc transporters (ZnTs) located there play important roles in this step. We have previously shown that two zinc transport complexes, ZnT5/ZnT6 heterodimers and ZnT7 homo-oligomers, are required for the activation of alkaline phosphatases, by converting them from the apo- to the holo-form. Here, we investigated the molecular mechanisms of this activation. ZnT1 and ZnT4 expressed in chicken DT40 cells did not contribute to the activation of tissue nonspecific alkaline phosphatase (TNAP). The reduced activity of TNAP in DT40 cells deficient in both ZnT complexes was not restored by zinc supplementation nor by exogenous expression of other ZnTs that increase the zinc content in the secretory pathway. Moreover, we showed that expression of ZnT5/ZnT6 heterodimers reconstituted with zinc transport-incompetent ZnT5 mutant failed to restore TNAP activity but could stabilize the TNAP protein as the apo-form, regardless of zinc status. These findings demonstrate that TNAP is activated not simply by passive zinc binding but by an elaborate two-step mechanism via protein stabilization followed by enzyme conversion from the apo- to the holo-form with zinc loaded by ZnT complexes in the early secretory pathway. 相似文献