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101.
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Limnology - In the original publication of the article the sentence under the heading “Primer and probe design” was published incorrectly. The correct sentence is given in this correction. 相似文献
103.
Seven ascidiacyclamide [cyclo(–Ile–oxazoline–d ‐Val–thiazole–)2] (ASC) analogues incorporating the β‐amino acids βIle, βoxazoline, and/or d ‐βVal were synthesized. We then investigated the effects of the position and number of incorporated β‐amino acids on the structure, cytotoxicity, and copper binding by these seven analogues. The structural analyses revealed that both βIle and d ‐βVal favor a gauche‐type θ torsion angles, while βoxazoline favors a trans‐type θ torsion angle. Expansion of the macrocycle by incorporation of βIle or d ‐βVal readily induced molecular folding. On the other hand, the incorporation of two βoxazoline residues strongly extended the peptide conformation, and the incorporation of one was sufficient for the moderate restriction important for conformational equilibrium and cytotoxicity. Despite expansion of the macrocycles, the structure‐cytotoxicity relationships were largely maintained. In studies of complexation of the analogues with Cu (II) ion, the position and number of incorporated β‐amino acids had a large impact on the structure of the metal complex and may contribute to its stabilization. 相似文献
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Qin Long Miki Naoko H. Zhang Guosheng Fujii Yoshiharu 《Landscape and Ecological Engineering》2021,17(3):245-251
Landscape and Ecological Engineering - Juniperus sabina L. is a native evergreen conifer of the Mu Us Sandy Land. It has prostrating stems that can prevent sand shifting and is an important... 相似文献
106.
Toshio Naka Takashi Doi Takeshi Tsujino Tohru Masuyama Seinosuke Kawashima 《Preparative biochemistry & biotechnology》2013,43(2):87-99
Abstract Viral vector systems are efficient for transfection of foreign genes into many tissues. Especially, retrovirus based vectors integrate the transgene into the genome of the target cells, which can sustain long term expression. However, it has been demonstrated that the transduction efficiency using retrovirus is relatively lower than those of other viruses. Ultrasound was recently reported to increase gene expression using plasmid DNA, with or without, a delivery vehicle. However, there are no reports, which show an ultrasound effect to retrovirus‐mediated gene transfer efficiency. Retrovirus‐mediated gene transfer systems were used for transfection of 293T cells, bovine aortic endothelial cells (BAECs), rat aortic smooth muscle cells (RASMCs), and rat skeletal muscle myoblasts (L6 cells) with β‐galactosidase (β‐Gal) genes. Transduction efficiency and cell viability assay were performed on 293T cells that were exposed to varying durations (5 to 30 seconds) and power levels (1.0 watts/cm2 to 4.0 watts/cm2) of ultrasound after being transduced by a retrovirus. Effects of ultrasound to the retrovirus itself was evaluated by transduction efficiency of 293T cells. After exposure to varying power levels of ultrasound to a retrovirus for 5 seconds, 293T cells were transduced by a retrovirus, and transduction efficiency was evaluated. Below 1.0 watts/cm2 and 5 seconds exposure, ultrasound showed increased transduction efficiency and no cytotoxicity to 293T cells transduced by a retrovirus. Also, ultrasound showed no toxicity to the virus itself at the same condition. Exposure of 5 seconds at the power of 1.0 watts/cm2 of an ultrasound resulted in significant increases in retrovirus‐mediated gene expression in all four cell types tested in this experiment. Transduction efficiencies by ultrasound were enhanced 6.6‐fold, 4.8‐fold, 2.3‐fold, and 3.2‐fold in 293T cells, BAECs, RASMCs, and L6 cells, respectively. Furthermore, β‐Gal activities were also increased by the retrovirus with ultrasound exposure in these cells. Adjunctive ultrasound exposure was associated with enhanced retrovirus‐mediated transgene expression in vitro. Ultrasound associated local gene therapy has potential for not only plasmid‐DNA‐, but also retrovirus‐mediated gene transfer. 相似文献
107.
Chemical Conversion of Some Ribonucleosides into the Corresponding β-D-Arabinofuranosyl Derivatives1
Nobuo Sakairi Ichiro Hirao Yoshiaki Zama Yoshiharu Ishido 《Nucleosides, nucleotides & nucleic acids》2013,32(3):221-229
Abstract Five 3′,5′-di-O-acylribonucleosides were converted into the corresponding β-D-arabinofuranosyl derivatives through DMSO-oxidation followed by NaBH4-reduction and deacylation with NaOMe-MeOH. 相似文献
108.
Kazuo Kamaike Yoshihiro Hasegawa Yoshiharu Ishido 《Nucleosides, nucleotides & nucleic acids》2013,32(1):37-43
Abstract 3′,5′-Di-O-benzoyl-2′-O-(tetrahydropyran-2-yl)uridine and 3′,5′ -di-O-benzoyl-N 2-isobutyryl-2′-O-(tetrahydropyran-2-yl)guanosine are converted into-N 3-anisoyl-2′-O-(tetrahydropyran-2-yl)uridine (less and more polar diastereoisomers in 37% and 42% yields, respectively) and O 6-diphenyl carbamoylN 2-isobutyryl-2′-O-(tetrahydropyran-2-yl)- guanosine (less and more polar diastereoisomers in 15% and 59% yields, respectively), respectively, by N 3-anisoylation and O 6-diphenylcarbamoylation, followed by 3′,5′-di-O-debenzoylation. 相似文献
109.
Kazuo Kamaike Tomohiro Ogawa and Yoshiharu Ishido 《Nucleosides, nucleotides & nucleic acids》2013,32(10):1015-1032
Abstract Synthesis of the title oligonucleotide bearing a phosphate function at the 5′-terminus, i.e., pCpUpCpGpUpCpCpApCpCpA, by the use of the terminal cytidylic acid unit involving a novel protecting group of 2-[2-(monomethoxytrityloxy)ethylthio]ethyl group on its 5′-phosphoryl function in terms of a cellulose acetate polymer-support is described. 相似文献
110.