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81.
Kunikazu Hiraga Takao Yokota Noboru Murofushi Nobutaka Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(2):345-347
Treatment of N6,N6,5′-O-tribenzoyl-2′,3′-O-isopropylidenetubercidin (VI) with aqueous acetic acid afforded N6,5′-O-dibenzoyltubercidin (V), which was mesylated to yield the dimesylate X. On treatment of X with sodium iodide and zinc dust, the 2′,3′-unsaturated derivatives of tubercidin XI and XIII were obtained.N6,5′-O-Dibenzoyltubercidin 2′,3′-thionocarbonate (XIV), prepared from V by treatment with Corey-Winter reagent, was converted to the 1-methyl-2′,3′-unsaturated derivative XV in refluxing trimethyl phosphite. 相似文献
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83.
Takayuki Abe Toshihmi Hatta Kazuyuki Takai Hideki Nakashima Tomoyuki Yokota Hiroshi Takaku 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):471-478
Abstract We have demonstrated that antisense phosphorothioate oligonucleotides (S-ODNs) inhibit influenza virus A replication in MDCK cells. Phosphorothioate and liposomally encapsulated oligonucleotides with two target sites (PB1 and PB2) were synthesized and tested for virus-induced cytopathogenicity effects by a MTT assay using MDCK cells. The liposomally encapsulated S-ODNs complementary to the sites of the PB2-AUG initiation codon showed highly inhibitory effects. On the other hand, the inhibitory effect of the liposomally encapsulated S-ODNs targeted to PB1 was considerably decreased in comparison with the PB2 target sites. The liposomally encapsulated oligonucleotides exhibited higher inhibitory activity than the free oligonucleotides. The activities of the modified oligonucleotides are effectively enhanced by using the liposomal carrier. 相似文献
84.
Tae Mogami Naho Yokota Mikiko Asai-Sato Roppei Yamada Shiro Koizume Yuji Sakuma Mitsuyo Yoshihara Yoshiyasu Nakamura Yasuo Takano Fumiki Hirahara Yohei Miyagi Etsuko Miyagi 《PloS one》2013,8(11)
Ovarian clear cell adenocarcinoma (CCC) is the second most common subtype of ovarian cancer after high-grade serous adenocarcinomas. CCC tends to develop resistance to the standard platinum-based chemotherapy, and has a poor prognosis when diagnosed in advanced stages. The ANXA4 gene, along with its product, a Ca++-binding annexin A4 (ANXA4) protein, has been identified as the CCC signature gene. We reported two subtypes of ANXA4 with different isoelectric points (IEPs) that are upregulated in CCC cell lines. Although several in vitro investigations have shown ANXA4 to be involved in cancer cell proliferation, chemoresistance, and migration, these studies were generally based on its overexpression in cells other than CCC. To elucidate the function of the ANXA4 in CCC cells, we established CCC cell lines whose ANXA4 expressions are stably knocked down. Two parental cells were used: OVTOKO contains almost exclusively an acidic subtype of ANXA4, and OVISE contains predominantly a basic subtype but also a detectable acidic subtype. ANXA4 knockdown (KO) resulted in significant growth retardation and greater sensitivity to carboplatin in OVTOKO cells. ANXA4-KO caused significant loss of migration and invasion capability in OVISE cells, but this effect was not seen in OVTOKO cells. We failed to find the cause of the different IEPs of ANXA4, but confirmed that the two subtypes are found in clinical CCC samples in ratios that vary by patient. Further investigation to clarify the mechanism that produces the subtypes is needed to clarify the function of ANXA4 in CCC, and might allow stratification and improved treatment strategies for patients with CCC. 相似文献
85.
86.
Ying-Xiao Li Kai-Chun Cheng Akihiro Asakawa Ikuo Kato Yuki Sato Haruka Amitani Namiko Kawamura Juei-Tang Cheng Akio Inui 《PloS one》2013,8(8)
Musclin is a novel skeletal muscle-derived secretory factor found in the signal sequence trap of mouse skeletal muscle cDNAs. Musclin possesses a region homologous to the natriuretic peptide family. Thus, musclin is found to bind with the natriuretic peptide clearance receptors. However, the role of musclin in vascular regulation remains unclear. In this study, we aim to investigate the direct effect of musclin on vascular tone and to analyze its role in hypertension using the spontaneously hypertensive rats (SHR). In aortic strips isolated from SHR, musclin induced contractions in a dose-dependent manner. We found that the musclin-induced vasoconstriction was more marked in SHR than in normal rats (WKY). Moreover, this contraction was reduced by blockade of natriuretic peptide receptor C using the ab14355 antibody. Therefore, mediation of the natriuretic peptide receptor in musclin-induced vasoconstriction can be considered. In addition, similar to the natriuretic peptide receptor, expression of the musclin gene in blood vessels was higher in SHR than in WKY. Injection of musclin markedly increased the blood pressure in rats that can be inhibited by anti-musclin antibodies. Musclin-induced vasoconstriction was more pronounced in SHR than in WKY as in its expression. Taken together, these results suggest that musclin is involved in blood pressure regulation. The higher expression of musclin in hypertension indicates that musclin could be used as a new target for the treatment of hypertension in the future. 相似文献
87.
Noboru Murofushi Nobutaka Takahashi Takao Yokota Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(10):1239-1245
A new gibberellin, gibberellin A20 (GA20), was isolated from immature seeds of morning-glory (Pharbitis nil). Its structure was established as 4aα, 7α-dihydroxy-1β-methyl-8-methylenegibbane-1α, 10β-dicarboxylic acid-1→4a lactone (I) on the basis of its physicochemical analysis as well as chemical evidences. GA20 shows marked growth promoting activities on dwarf maize d2 and d5 but weak activities on d1, rice seedling and dwarf pea. 相似文献
88.
Keun-Hyung Park Takao Yokota Akira Sakurai Nobutaka Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(11):3081-3086
The rice lamina inclination test indicated the presence of brassinosteroid-like active substances in immature Vicia faba seeds. Two of these were identified as castasterone and brassinolide by GC/MS and GC/SIM, respectively. Another active principle was identified as methyl 4- chloroindole-3-acetate by GC/MS and HPLC. 相似文献
89.
90.
Kunikazu Hiraga Susumu Kawabe Takao Yokota Noboru Murofushi Nobutaka Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(12):2521-2527
From the immature seeds of Phaseolus vulgaris cv. Kentucky Wonder GA1, GA8, GA38, ABA and GA8 glucoside were isolated, and GA4, GA5, GA6 and GA37 were identified by GC or GC-MS. Unknown substance, AB–II, was also suggested to be present in the immature seeds. In the etiolated seedlings glucosyl esters of GA1 and GA38 were identified by GC. GA8 glucoside and AB–II were shown to be present by the histograms. 相似文献