Akihiro Okano

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The purpose of this investigation was to determine the effect of beta-mercaptoethanol (beta-ME) and cysteamine, low-molecular-weight thiol compounds, on the development and intracellular glutathione content of bovine embryos obtained by in vitro fertilization of in vitro-matured oocytes. Embryos developed to the 6-8-cell stage after in vitro fertilization(More)
BACKGROUND Endoscopic mucosal resection has been increasingly used to treat gastric tumors. Bleeding is the major complication of endoscopic mucosal resection. This study evaluated risk factors for bleeding associated with endoscopic mucosal resection. METHODS Four hundred seventy-seven patients who underwent endoscopic mucosal resection of gastric tumors(More)
The correlation of oxidative stress on development and DNA damage in bovine embryos was investigated by the comet assay (single-cell microgel electrophoresis), an effective technique for detecting single-strand DNA breakage. After in vitro maturation and fertilization, one-cell stage embryos without cumulus cells were cultured for 8 days in SOF medium(More)
DNA damage induced by either light exposure or oxidative stress likely contributes to the compromised development in vitro of cultured preimplantation embryos. Using the comet assay, which entails microgel electrophoresis that can readily detect single-strand breaks in DNA, a significant increase in DNA damage was detected in individual one-cell hamster(More)
The effects of beta-mercaptoethanol (beta-ME) on in vitro development under oxidative stress and cystine uptake of bovine embryos were investigated. Bovine 1-cell embryos obtained by in vitro fertilization were cultured in TCM-199 or synthetic oviductal fluid (SOF) in 20% O(2) supplemented with beta-ME. Addition of beta-ME significantly (P < 0.01) promoted(More)
BSF-2 (B cell stimulatory factor-2/IL-6) is a member of the lymphokine family and responsible for B cell differentiation. Expression plasmids of human BSF-2 cDNA were constructed using a trp promotor/operator and a trpA terminator. In an extract of Escherichia coli HB101 holding "direct" expression plasmid pBSF-2D, activity of BSF-2 was detected, but(More)
In cynomolgus monkeys, twice daily subcutaneous injections of recombinant human interleukin-6 (rhIL-6) at doses of 5 to 80 micrograms/kg/d for 14 consecutive days caused dose-dependent increases in platelet count, usually continuing for more than 1 week after cessation of the injections. The count reached a level approximately twofold or more above the(More)
Interleukin-6 (IL-6), a multipotential cytokine, initiates signal transduction pathways similar to those of ciliary neurotrophic factor (CNTF) and leukemia inhibitory factor (LIF). These molecules share the signal transducing receptor component, gp130. IL-6 triggers homodimerization of gp130, whereas CNTF and LIF induce heterodimerization of gp130 and LIF(More)
Tubulin binding agents (TBAs) reduce tumor perfusion and inhibit mitosis of tumor cells in solid tumors, but it is not clear which effects contribute to the suppression of solid tumor growth. We evaluated the antivascular and antimitotic effects of several TBAs, combretastatin A-4 (CS A-4) phosphate, AC-7700, a novel CS A-4 derivative, colchicine, E7010,(More)
AC-7700, a novel combretastatin A-4 derivative, suppresses the growth of solid tumors by inhibiting tumor perfusion. We evaluated the antitumor activity of AC-7700 on solid tumors in two experimental models, an advanced tumor model (murine colon 26 (c26) adenocarcinoma, colon 38 (c38) adenocarcinoma, MethA fibrosarcoma, Sarcoma 180 (S180), Lewis lung(More)