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71.
Sakiyama Tomoki Morimoto Junko Matsubayashi Jun Furukawa Yasuto Kondo Mami Tsuruga Hifumi Mano Tsutomu Nakamura Futoshi 《Landscape and Ecological Engineering》2021,17(3):351-362
Landscape and Ecological Engineering - Investigating factors underlying human-wildlife conflicts in agricultural landscapes is important for both preventing crop damage and wildlife conservation.... 相似文献
72.
73.
Takafumi Watanabe Hideaki Nanamiya Manabu Kojima Shinji Nomura Shigenori Furukawa Shu Soeda Daisuke Tanaka Takao Isogai Jun-ichi Imai Shinya Watanabe Keiya Fujimori 《Translational oncology》2021,14(3):101010
PurposeEndometrial carcinoma (EC) is a clinically heterogeneous disease characterized by a number of different histological subtypes, and its heterogeneity may be involved in the accumulation of multiple genetic alterations. The aim of this work was to investigate the comprehensive mutational profile of EC tumors, and examine the associations between somatic mutations and clinicopathological features or survival in EC patients.MethodsA total of 100 surgical tumors were obtained from EC patients who had previously undergone surgery. Genomic DNA samples extracted from fresh-frozen tissues were analyzed using the Ion AmpliSeq Cancer Hotspot Panel v2 Kit, covering 50 tumor-related genes.ResultsValidated mutations were detected in 91 of the 100 tumors (91%) and identified in eight of the most frequently mutated genes, namely PTEN (57%), PIK3CA (51%), TP53 (30%), KRAS (23%), CTNNB1 (21%), FBFR2 (13%), FBXW7(10%) and RB1 (9%). PTEN mutations were found to associated with young age (< 60), early-stage, endometrioid histology, non-recurrence and better overall survival (OS). CTNNB1 mutations were associated with young age, endometrioid histology and better OS. On the other hands, TP53 mutations were associated with late-stage, non-endometrioid histology, high-grade, recurrence and worse OS. FBWX7 mutations were associated with late-stage, vascular invasion and lymph node metastasis. FGFR2 mutations correlated with deep (≥ 1/2) myometrial invasion.ConclusionOur comprehensive mutational profile will be useful for understanding and evaluating the molecular characteristics of EC tumors, and may lead to the establishment of novel treatment strategies that improve the survival of patients with EC in the future. 相似文献
74.
Nobuho Tanaka Yasuko Ikeda Tetsuo Yamaguchi Hiroshi Furukawa Hiroyuki Mitomi Takumi Nakagawa Shigeto Tohma Naoshi Fukui 《Arthritis research & therapy》2013,15(5):R127
Introduction
Articular chondrocytes undergo an obvious phenotypic change when cultured in monolayers. During this change, or dedifferentiation, the expression of type I and type III procollagen is induced where normal chondrocytes express little type I and type III procollagen. In this study, we attempted to determine the mechanism(s) for the induction of such procollagen expression in dedifferentiating chondrocytes.Methods
All experiments were performed using primary-cultured human articular chondrocytes under approval of institutional review boards. Integrin(s) responsible for the induction of type I and type III procollagen expression were specified by RNAi experiments. The signal pathway(s) involved in the induction were determined by specific inhibitors and RNAi experiments. Adenovirus-mediated experiments were performed to identify a small GTPase regulating the activity of integrins in dedifferentiating chondrocytes. The effect of inhibition of integrins on dedifferentiation was investigated by experiments using echistatin, a potent disintegrin. The effect of echistatin was investigated first with monolayer-cultured chondrocytes, and then with pellet-cultured chondrocytes.Results
In dedifferentiating chondrocytes, α5β1 integrin was found to be involved in the induction of type I and type III procollagen expression. The induction was known to be mediated by v-akt murine thymoma viral oncogene homolog (AKT) signaling. Among the three AKT isoforms, AKT1 seemed to be most involved in the signaling. Elated RAS viral (r-ras) oncogene homolog (RRAS) was considered to regulate the progression of dedifferentiation by modulating the affinity and avidity of α5β1 integrin to ligands. Echistatin inhibited dedifferentiation of monolayer-cultured chondrocytes. Furthermore, the matrix formed by pellet-cultured chondrocytes more closely resembled that of normal cartilage compared with the controls.Conclusions
The result of this study has shown, for the first time, that α5β1 integrin may be responsible for the induction of non-cartilaginous collagen expression in chondrocytes undergoing dedifferentiation. Again, this study has shown that the inhibition of ligand ligation to integrins may be an effective strategy to inhibit phenotypic change of cultured chondrocytes, and to improve the quality of matrix synthesized by primary cultured chondrocytes. 相似文献75.
Hideo Inoue Masaki Shimizu Takako Furukawa Takashi Tamura Miwa Matsui Eiko Ohtsuka 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1503-1505
Abstract 2′-Deoxy- and 2′-O-methyl-5′-O-terpyridyl derivatives of adenosine and cytidine were synthesized and used to construct 5′-end-modified oligonucleotides. These antisense agents complexed with Cu(II) exclusively cleaved a complementary RNA oligomer at the site opposite the terpyridine-nucleoside residue. We also found that the terpyridine·Cu(II) moiety stabilizes 2′-O-methyl RNA duplex. These suggest that after RNA hybridization, the terpyridine moiety is close to the RNA strand, presumably in an end capping manner. 相似文献
76.
Kenta Shirasawa Kohei Ishii Cholgwang Kim Tomohiro Ban Munenori Suzuki Takashi Ito Toshiya Muranaka Megumi Kobayashi Noriko Nagata Sachiko Isobe Satoshi Tabata 《Molecular breeding : new strategies in plant improvement》2013,31(1):101-110
Capsicum spp. are widely cultivated for use as vegetables and spices. The Kihara Institute for Biological Research, Yokohama City University, Japan, has stocks of approximately 800 lines of Capsicum spp. collected from various regions of Central and South America, the regions of origin for Capsicum spp. In this study, 5,751 primer pairs for simple sequence repeat markers, based on 118,060 publicly available sequences of expressed sequence tags of Capsicum annuum, were designed and subjected to a similarity search against the genomic sequence of tomato, a model Solanaceae species. Nucleotide sequences spanning 2,245 C. annuum markers were successfully mapped onto the tomato genome, and 96 of these, which spanned the entire tomato genome, were selected for further analysis. In genotyping analysis, 60 out of the 77 markers that produced specific DNA amplicons showed polymorphism among the Capsicum lines examined. On the basis of the resulting data, the 192 tested lines were grouped into five main clusters. The additional sequencing analysis of the plastid genes, matK and rbcL, divided the resources into three groups. As a result, 19 marker loci exhibited genotypes specific to species and cluster, suggesting that the DNA markers are useful for species identification. Information on the DNA markers will contribute to Capsicum genetics, genomics, and breeding. 相似文献
77.
Mayumi Yoshihara Hiroshi Akasaka Hirofumi Ohnishi Takayuki Miki Tetsuaki Furukawa Satoshi Yuda Shigeyuki Saitoh Tetsuji Miura 《PloS one》2013,8(7)
Aims
Roles of glucagon-like peptide-1 (GLP-1) in extra-pancreatic tissues remain unclear. The aim of this study was to examine determinants of GLP-1 secretory function and possible contribution of GLP-1 to blood pressure (BP) regulation.Methods and Results
We recruited 128 subjects who received annual examinations and 75g-oral glucose tolerance tests (OGTT) in the Tanno-Sobetsu cohort. Subjects on regular medications for cardiovascular and/or metabolic diseases were excluded, and data for the remaining 103 subjects were used for the univariate and multivariate analyses. Age, plasma glucose (PG), hemoglobin A1c (HbA1c), plasma insulin, and serum lipids were not selected as independent determinants of fasting GLP-1 level by multiple linear regression analysis. However, age and female sex were selected as independent positive determinants of the area under the curve of GLP-1 level during OGTT (AUCGLP-1), an index of GLP-1 secretory function. Multiple linear regression analysis indicated that AUCGLP-1 was an independent negative predictor of systolic BP (SBP), while AUCGLP-1 was not correlated with fasting PG or HbA1c level. In subgroup analyses using the median of AUCGLP-1 to divide the study subjects into high and low GLP-1 response groups, AUCGLP-1 was significantly correlated with both SBP and diastolic BP (r = 0.40 and 0.28, respectively) in the low GLP-1 response group but not in the high GLP-1 response group.Conclusions
The results of the present study suggest that GLP-1 secretory function is involved in prevention of BP elevation and that the GLP-1 response to oral glucose rather increases with aging perhaps as an adaptive phenomenon. 相似文献78.
Kiyoshi Migita Toru Arai Naoki Ishizuka Yuka Jiuchi Yasuharu Sasaki Yasumori Izumi Tetsuyuki Kiyokawa Eiichi Suematsu Tomoya Miyamura Hiroshi Tsutani Yojiro Kawabe Ryutaro Matsumura Shunsuke Mori Shiro Ohshima Shigeru Yoshizawa Kenji Kawakami Yasuo Suenaga Hideo Nishimura Toyohiko Sugimoto Hiroaki Iwase Hideyuki Sawada Haruhiro Yamashita Shigeyuki Kuratsu Fumitaka Ogushi Masaharu Kawabata Toshihiro Matsui Hiroshi Furukawa Seiji Bito Shigeto Tohma 《PloS one》2013,8(11)
Background/Aims
The Japanese National Hospital Organization evidence-based medicine (EBM) Study group for Adverse effects of Corticosteroid therapy (J-NHOSAC) is a Japanese hospital-based cohort study investigating the safety of the initial use of glucocorticoids (GCs) in patients with newly diagnosed autoimmune diseases. Using the J-NHOSAC registry, the purpose of this observational study is to analyse the rates, characteristics and associated risk factors of intracellular infections in patients with newly diagnosed autoimmune diseases who were initially treated with GCs.Methodology/Principal Findings
A total 604 patients with newly diagnosed autoimmune diseases treated with GCs were enrolled in this registry between April 2007 and March 2009. Cox proportional-hazards regression was used to determine independent risk factors for serious intracellular infections with covariates including sex, age, co-morbidity, laboratory data, use of immunosuppressants and dose of GCs. Survival was analysed according to the Kaplan-Meier method and was assessed by the log-rank test. There were 127 serious infections, including 43 intracellular infections, during 1105.8 patient-years of follow-up. The 43 serious intracellular infections resulted in 8 deaths. After adjustment for covariates, diabetes (Odds ratio [OR]: 2.5, 95% confidence interval [95% CI] 1.1–5.9), lymphocytopenia (≦1000/μl, OR: 2.5, 95% CI 1.2–5.2) and use of high-dose (≧30 mg/day) GCs (OR: 2.4, 95% CI 1.1–5.3) increased the risk of intracellular infections. Survival curves showed lower intracellular infection-free survival rate in patients with diabetes, lymphocytopaenia and high-dose GCs treatments.Conclusions/Significance
Patients with newly diagnosed autoimmune diseases were at high risk of developing intracellular infection during initial treatment with GCs. Our findings provide background data on the risk of intracellular infections of patients with autoimmune diseases. Clinicians showed remain vigilant for intracellular infections in patients with autoimmune diseases who are treated with GCs. 相似文献79.
80.
Muichi Kaito Shin-Ichi Araya Yuichiro Gondo Michiyo Fujita Naomi Minato Megumi Nakanishi Makoto Matsui 《PloS one》2013,8(8)