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101.
Hiroshi Takaku Tetsuo Watanabe Shoji Hamamoto 《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):293-296
Abstract 2-(2-Pyridyl)ethyl is a new protecting group for the internucleotidic linkages in the synthesis of oligodeoxyribo-nucleotides by the phosphoramidite method. This group is stable to alkali and acid, and can be removed by two step procedures under mild conditions. Furthermore, we have found that bis-(diiso-propylamino)chlorophosphine is much more effective for the preparation of bis-(diisopropylamino)alkoxyphosphine than various dichlorophosphines. The synthesis of oligodeoxyribonucleotides by using 2-(2-pyridyl)ethyl-deoxyribonucleoside-3′-0-N,N-diisopropyl-amidite units is also described. 相似文献
102.
Haruo Ogura Hiroshi Takahashi Kikuko Ohokubo 《Nucleosides, nucleotides & nucleic acids》2013,32(2):147-154
Abstract The reaction of glycosyl isothiocyanates (la, b, c, d, e) with 5,6-diamino-1-3-dimethyluracil gave the respective 1-glycosyl-3-(6-amino-1, 3-dimethyl-2, 4-dioxopyrimidine-5-yl) thioureas (2a, b, c, d, e) in excellent yields. Treatment of these thioureas with NBS afforded the respective 5,7-dioxopyrimido-[5,4-e]-as-triazine glycosides (4a, b, c, d, e) in good yields. 相似文献
103.
Masaaki Hayafune Naoko Miyano-Kurosaki Hiroshi Takaku Wee-Sung Park 《Nucleosides, nucleotides & nucleic acids》2013,32(7):795-799
The RNA interference (RNAi) phenomenon is a recently observed process in which the introduction of a double-stranded RNA (dsRNA) into cells causes the specific degradation of an mRNA containing the same sequence. To study dsRNA-mediated gene interference targeted to the env gene (NL4-3: 7490-7508) in HIV-1 infected cells, we constructed tandem-type and hairpin-type siRNA expression vectors, which were under the control of two U6 promoters. We also constructed lentiviral-based siRNA expression vectors for further assessment of their antiviral activity in transduced cells. At both the transient plasmid and lentiviral-mediated RNA expression levels, the siRNA encoding the env fragment exhibited sequence-specific suppression of target gene expression and strongly inhibited (≥90%) HIV-1 infection in the cells, as compared to the antisense RNA expression vector. Targeting the HIV-1 env gene with siRNAs encoding the env gene fragment (7490–7508) might be an effective strategy for gene therapy applications in HIV-1/AIDS treatment and management. 相似文献
104.
Parasporin 1Ac2, a Novel Cytotoxic Crystal Protein Isolated from Bacillus thuringiensis B0462 Strain
Shouta Kuroda Anowara Begum Mizue Saga Akina Hirao Eiichi Mizuki Hiroshi Sakai Tohru Hayakawa 《Current microbiology》2013,66(5):475-480
Two novel parasporin (PS) genes were cloned from Bacillus thuringiensis B0462 strain. One was 100 % identical even in nucleotide sequence level with that of parasporin-1Aa (PS1Aa1) from B. thuringiensis A1190 strain. The other (PS1Ac2) showed significant homology (99 % identity) to that of PS1Ac1 from B. thuringiensis 87-29 strain. The 15 kDa (S113–R250) and 60 kDa (I251–S777) fragments consisting of an active form of PS1Ac2 were expressed as His-tag fusion. Upon purification under denaturing condition and refolding, the recombinant polypeptides were applied to cancer cells to analyze their cytotoxicities. 3-(4,5-Dimethyl-2-thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide assay revealed that either of 15 or 60 kDa polypeptide exhibited no cytotoxicity to HeLa cells, but they became cytotoxic upon mixed together. Our results suggested that PS1Ac2 was responsible for the cytotoxicity of B. thuringiensis B0462 strain, and that the formation of hetero-dimer of 15 and 60 kDa polypeptide was required for their cytotoxicity. 相似文献
105.
Akira Nakajima Yuto Ueda Emiko Matsuda Hiroshi Sameshima Tsuyomu Ikenoue 《Neurochemical research》2013,38(7):1360-1364
The effect of the oral administration of mimosa tannin (MMT) on the rat intra-hippocampal antioxidant ability was examined. Wistar rats at the age of 6 weeks were reared for 8 weeks with the rodent diet (RD) consisting of 0.1 g/kg of MMT (RD–MMT). The antioxidant ability of rat brain was evaluated from the decay of a brain–blood-barrier permeable stable nitroxide, 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (PCAM) measured by the microdialysis-electron spin resonance system under a freely moving state. The decay rate of PCAM in the brain of rats fed RD–MMT was significantly larger than that of rats fed control rodent diet, which indicates the increase of the antioxidant ability in the brain of rats fed RD–MMT. In vitro study showed that MMT did not reduce PCAM directly but enhanced the reduction of PCAM by ascorbic acid. These results indicate that MMT is a potent antioxidant in vitro and in vivo. 相似文献
106.
Toshiyuki Yamaguchi Romanus Edy Prabowo Yuu Ohshiro Takaki Shimono Diana Jones Hiroshi Kawai 《Biofouling》2013,29(4):325-333
The Titan Acorn barnacle, Megabalanus coccopoma, a native of the tropical eastern Pacific, has become established in the western Atlantic (Brazil and the northern Gulf of Mexico to the Carolinas), northwestern Europe and the western Indian Ocean (Mauritius), and therefore its dispersal capabilities are well known. This study reports its introduction to Japan and confirms its occurrence in Australia. In an attempt to determine the source of this introduction, phylogeographic techniques, involving cytochrome c oxidase I sequences of various widely separate populations of M. rosa and M. volcano, were utilized. No significant genetic differentiation or haplotype patterns between widely separated populations of each of the three species were found. Lack of such differentiation indicates recent geographical isolation and thus negates a null hypothesis predicting that the occurrence of one of more of these species in Australia was natural. 相似文献
107.
Abstract Structural aspects of BaB2O4 liquids have been investigated by the molecular dynamics simulation including the determination on the parameters of the interatomic potential applicable to BaB2O4 in both crystalline and molten states. The structure and physical properties of BaB2O4 crystals were successfully reproduced by the MD simulation for both α and β phases. The simulated interference function in the liquid state was also in good agreement with the experimental one. Several interesting features on the relaxation phenomena just after melting were reproduced by the simulation that the structure factors of simulated liquid maintain the characteristic features of the original crystal structure for more than 40ps after melting, and the variation of the number of rings formed by B-O bondings was found to increase after melting. 相似文献
108.
Hiroshi Katoh Toru Okamoto Takasuke Fukuhara Hiroto Kambara Eiji Morita Yoshio Mori Wataru Kamitani Yoshiharu Matsuura 《Journal of virology》2013,87(1):489-502
Stress granules (SGs) are cytoplasmic foci composed of stalled translation preinitiation complexes induced by environmental stress stimuli, including viral infection. Since viral propagation completely depends on the host translational machinery, many viruses have evolved to circumvent the induction of SGs or co-opt SG components. In this study, we found that expression of Japanese encephalitis virus (JEV) core protein inhibits SG formation. Caprin-1 was identified as a binding partner of the core protein by an affinity capture mass spectrometry analysis. Alanine scanning mutagenesis revealed that Lys97 and Arg98 in the α-helix of the JEV core protein play a crucial role in the interaction with Caprin-1. In cells infected with a mutant JEV in which Lys97 and Arg98 were replaced with alanines in the core protein, the inhibition of SG formation was abrogated, and viral propagation was impaired. Furthermore, the mutant JEV exhibited attenuated virulence in mice. These results suggest that the JEV core protein circumvents translational shutoff by inhibiting SG formation through an interaction with Caprin-1 and facilitates viral propagation in vitro and in vivo. 相似文献
109.
A New Species of the Genus Colilodion Besuchet (Coleoptera: Staphylinidae: Pselaphinae) from Vietnam
A new pselaphine species, Colilodion thienmu n. sp., is described from Mt. Bach Ma in Central Vietnam. SEM photographs of this species are provided and morphological notes are given in this study. 相似文献
110.
Ken-ichiro Tanaka Toru Yamaguchi Hiroshi Kaji Ippei Kanazawa Toshitsugu Sugimoto 《Biochemical and biophysical research communications》2013
Advanced glycation end products (AGEs) are involved in bone quality deterioration in diabetes mellitus. We previously showed that AGE2 or AGE3 inhibited osteoblastic differentiation and mineralization of mouse stromal ST2 cells, and also induced apoptosis and decreased cell growth. Although quality management for synthesized proteins in endoplasmic reticulum (ER) is crucial for the maturation of osteoblasts, the effects of AGEs on ER stress in osteoblast lineage are unknown. We thus examined roles of ER stress in AGE2- or AGE3-induced suppression of osteoblastogenesis of ST2 cells. An ER stress inducer, thapsigargin (TG), induced osteoblastic differentiation of ST2 cells by increasing the levels of Osterix, type 1 collagen (Col1), alkaline phosphatase (ALP) and osteocalcin (OCN) mRNA. AGE2 or AGE3 suppressed the levels of ER stress sensors such as IRE1α, ATF6 and OASIS, while they increased the levels of PERK and its downstream molecules, ATF4. A reduction in PERK level by siRNA did not affect the AGEs-induced suppression of the levels of Osterix, Col1 and OCN mRNA. In conclusion, AGEs inhibited the osteoblastic differentiation of stromal cells by suppressing ER stress sensors and accumulating abnormal proteins in the cells. This process might accelerate AGEs-induced suppression of bone formation found in diabetes mellitus. 相似文献