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991.
Shugo Tohyama Fumiyuki Hattori Motoaki Sano Takako Hishiki Yoshiko Nagahata Tomomi Matsuura Hisayuki Hashimoto Tomoyuki Suzuki Hiromi Yamashita Yusuke Satoh Toru Egashira Tomohisa Seki Naoto Muraoka Hiroyuki Yamakawa Yasuyuki Ohgino Tomofumi Tanaka Masatoshi Yoichi Shinsuke Yuasa Keiichi Fukuda 《Cell Stem Cell》2013,12(1):127-137
Highlights? Integrated “omic” analyses reveal metabolic hallmarks in ESCs and cardiomyocytes ? Glucose depletion and lactate supplementation can purify PSC-derived cardiomyocytes ? Cardiomyocytes can use lactate efficiently for energy metabolism ? Transplanted purified human ESC-derived cardiomyocytes do not form tumors 相似文献
992.
993.
Taisuke Matsuo Takenori Yamamoto Chie Katsuda Kanami Niiyama Atsushi Yamamoto Naoshi Yamazaki Kazuto Ohkura Masatoshi Kataoka Yasuo Shinohara 《Biologicals》2009,37(1):44-47
Substitution of amino acids in a peptide caused remarkable differences in its immunoreactivities with antibodies against 3 epitopes in the immobilized peptide. The observed differences in immunoreactivities among the peptides were not due to the differences in efficiencies of their transfer onto nitrocellulose or PVDF membranes. Rather, possible folding of the peptide on the membrane was considered to be the reason for their distinct immunoreactivities with the antibodies. 相似文献
994.
995.
Tsukasa Takahashi Kisaburo Hanazawa Takashi Inoue Kenya Sato Ayako Sedohara Junko Okahara Hiroshi Suemizu Chie Yagihashi Masafumi Yamamoto Tomoo Eto Yusuke Konno Hideyuki Okano Makoto Suematsu Erika Sasaki 《PloS one》2014,9(4)
Intracytoplasmic sperm injection (ICSI), an important method used to treat male subfertility, is applied in the transgenic technology of sperm-mediated gene transfer. However, no study has described successful generation of offspring using ICSI in the common marmoset, a small non-human primate used as a model for biomedical translational research. In this study, we investigated blastocyst development and the subsequent live offspring stages of marmoset oocytes matured in vitro and fertilized by ICSI. To investigate the optimal timing of performing ICSI, corrected immature oocytes were matured in vitro and ICSI was performed at various time points (1–2 h, 2–4 h, 4–6 h, 6–8 h, and 8–10 h after extrusion of the first polar body (PB)). Matured oocytes were then divided randomly into two groups: one was used for in vitro fertilization (IVF) and the other for ICSI. To investigate in vivo development of embryos followed by ICSI, 6-cell- to 8-cell-stage embryos and blastocysts were nonsurgically transferred into recipient marmosets. Although no significant differences were observed in the fertilization rate of blastocysts among ICSI timing after the first PB extrusion, the blastocyst rate at 1–2 h was lowest among groups at 2–4 h, 4–6 h, 6–8 h, and 8–10 h. Comparing ICSI to IVF, the fertilization rates obtained in ICSI were higher than in IVF (p>0.05). No significant difference was noted in the cleaved blastocyst rate between ICSI and IVF. Following the transfer of 37 ICSI blastocysts, 4 of 20 recipients became pregnant, while with the transfer of 21 6-cell- to 8-cell-stage ICSI embryos, 3 of 8 recipients became pregnant. Four healthy offspring were produced and grew normally. These are the first marmoset offspring produced by ICSI, making it an effective fertilization method for marmosets. 相似文献
996.
Hiroko Ogata-Kawata Masashi Izumiya Daisuke Kurioka Yoshitaka Honma Yasuhide Yamada Koh Furuta Toshiaki Gunji Hideki Ohta Hiroyuki Okamoto Hikaru Sonoda Masatoshi Watanabe Hitoshi Nakagama Jun Yokota Takashi Kohno Naoto Tsuchiya 《PloS one》2014,9(4)
Purpose
Exosomal microRNAs (miRNAs) have been attracting major interest as potential diagnostic biomarkers of cancer. The aim of this study was to characterize the miRNA profiles of serum exosomes and to identify those that are altered in colorectal cancer (CRC). To evaluate their use as diagnostic biomarkers, the relationship between specific exosomal miRNA levels and pathological changes of patients, including disease stage and tumor resection, was examined.Experimental Design
Microarray analyses of miRNAs in exosome-enriched fractions of serum samples from 88 primary CRC patients and 11 healthy controls were performed. The expression levels of miRNAs in the culture medium of five colon cancer cell lines were also compared with those in the culture medium of a normal colon-derived cell line. The expression profiles of miRNAs that were differentially expressed between CRC and control sample sets were verified using 29 paired samples from post-tumor resection patients. The sensitivities of selected miRNAs as biomarkers of CRC were evaluated and compared with those of known tumor markers (CA19-9 and CEA) using a receiver operating characteristic analysis. The expression levels of selected miRNAs were also validated by quantitative real-time RT-PCR analyses of an independent set of 13 CRC patients.Results
The serum exosomal levels of seven miRNAs (let-7a, miR-1229, miR-1246, miR-150, miR-21, miR-223, and miR-23a) were significantly higher in primary CRC patients, even those with early stage disease, than in healthy controls, and were significantly down-regulated after surgical resection of tumors. These miRNAs were also secreted at significantly higher levels by colon cancer cell lines than by a normal colon-derived cell line. The high sensitivities of the seven selected exosomal miRNAs were confirmed by a receiver operating characteristic analysis.Conclusion
Exosomal miRNA signatures appear to mirror pathological changes of CRC patients and several miRNAs are promising biomarkers for non-invasive diagnosis of the disease. 相似文献997.
Hiroki Sakakura Yoshiki Murakumo Shinji Mii Sumitaka Hagiwara Takuya Kato Masato Asai Akiyoshi Hoshino Noriyuki Yamamoto Sayaka Sobue Masatoshi Ichihara Minoru Ueda Masahide Takahashi 《PloS one》2014,9(1)
CD109, a glycosylphosphatidylinositol-anchored glycoprotein, is expressed at high levels in some human tumors including squamous cell carcinomas. As CD109 is reportedly cleaved by furin and its soluble form is secreted into culture medium in vitro, we hypothesized that CD109 could serve as a tumor marker in vivo. In this study, we investigated CD109 as a novel serum tumor marker using transgenic mice that overexpress mouse CD109 (mCD109-TG mice) and tumor xenografted mice inoculated with human CD109 (hCD109)-overexpressing HEK293 cells. In sera and urine of mCD109-TG mice, mCD109 was detected using western blotting. In xenografted mice, hCD109 secreted from inoculated tumors was detected in sera, using western blotting and CD109 ELISA. Concentrations of tumor-secreted CD109 increased proportionally as tumors enlarged. Concentrations of secreted CD109 decreased notably by 17 h after tumor resection, and became undetectable 48 h after resection. The half-life of tumor-secreted CD109 was about 5.86±0.17 h. These results indicate that CD109 is present in serum as a soluble form, and suggest its potential as a novel tumor marker in patients with cancers that express CD109. 相似文献
998.
Minoru Sasaki Masatoshi Kondo Kohji Sato Mai Umeda Keigo Kawabata Yoshito Takahashi Tamio Suzuki Kayoko Matsunaga Shintaro Inoue 《Pigment cell & melanoma research》2014,27(5):754-763
Rhododendrol, an inhibitor of melanin synthesis developed for lightening/whitening cosmetics, was recently reported to induce a depigmentary disorder principally at the sites of repeated chemical contact. Rhododendrol competitively inhibited mushroom tyrosinase and served as a good substrate, while it also showed cytotoxicity against cultured human melanocytes at high concentrations sufficient for inhibiting tyrosinase. The cytotoxicity was abolished by phenylthiourea, a chelator of the copper ions at the active site, and by specific knockdown of tyrosinase with siRNA. Hence, the cytotoxicity appeared to be triggered by the enzymatic conversion of rhododendrol to active product(s). No reactive oxygen species were detected in the treated melanocytes, but up‐regulation of the CCAAT‐enhancer‐binding protein homologous protein gene responsible for apoptosis and/or autophagy and caspase‐3 activation were found to be tyrosinase dependent. These results suggest that a tyrosinase‐dependent accumulation of ER stress and/or activation of the apoptotic pathway may contribute to the melanocyte cytotoxicity. 相似文献
999.
Kiho T Nakayama M Yasuda K Miyakoshi S Inukai M Kogen H 《Bioorganic & medicinal chemistry letters》2003,13(14):2315-2318
Globomycin, a signal peptidase II inhibitor, and its derivatives show potent antibacterial activity against Gram-negative bacteria. The synthesis and antimicrobial activity of novel globomycin analogues are reported. One of the analogues showed a more potent activity against Gram-negative bacteria than globomycin and also exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). 相似文献
1000.
Minamikawa-Tachino R Kabuyama N Gotoh T Kagei S Naruse M Kisu Y Togashi T Sugano S Usami H Nomura N 《Comptes rendus biologies》2003,326(10-11):993-1001
The sequence of the human genome has been determined. The next task is to determine the function of the genes. Classifying cellular forms of proteins encoded by human cDNA clones is a primary step toward understanding the biological role of proteins and their coding genes. We report here our ongoing work on an automatic system to facilitate this classification. Our system handles the transfection, incubation, acquisition of microscopic images of the cells, and the classification of forms there appearing in the images. Our system correctly classified proteins by their forms at a rate of 90% in feasibility studies. 相似文献