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41.
Toshiaki Nagafuji Tohru Koide Tatsuo Miyauchi Michiaki Takato 《Journal of neurochemistry》1992,58(1):362-368
In search of factors mitigating the final outcome of ischemic and epileptic brain damage, we tested a novel dibenzoxazepine derivative (BY-1949), as the compound has been shown to be effective under these two conditions. First, using rat brain, we assessed whether or not BY-1949 affects the Na+,K(+)-ATPase activity. Although in vitro applications of either BY-1949 or its three major metabolites did not cause any apparent effects, both acute and chronic oral administrations of the compound (10 mg/kg) invariably increased the Na+,K(+)-ATPase activity in the synaptosomal plasma membranes by increasing Vmax values. Second, it was shown by this study that the drug treatment caused marked increases in the uptake of both glutamic acid and gamma-aminobutyric acid into the synaptosomes. These results suggest that the activity against ischemic/epileptic brain damage by BY-1949 is explicable, at least partly, in terms of improvement of ionic derangements across the neural membranes via Na+,K(+)-ATPase activation. 相似文献
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Corelike structures, which were interpreted as straight, large cylinders containing ribosome-like particles surrounded by
an amorphous substance of low electron density, were found in a stable L-form ofStreptococcus pyogenes grown in the absence of antibiotics. 相似文献
45.
Saito Masahiko; Kondo Noriaki; Yamaguchi Hisao; Hashimoto Tohru 《Plant & cell physiology》1976,17(3):411-416
Nine bibenzyls and 10 stilbenes were synthesized as analoguesof batatasin III, a growth inhibitor isolated from dormant yambulbils, and examined for their plant growth-regulating activities.The bioassays used were the elongation of dark-grown intactrice coleoptiles, auxin-induced elongation of excised oat coleoptiles,and germination of rape and barnyard grass seeds. In the elongationof intact rice coleoptiles, 3,3'-dihydroxy-5-methoxy- (batatasinIII), 3,5-dimethoxy-3'-nitro-, 4'-bromo-3-nitro-, 3-amino-3'-chloro-,3-amino-4'-chloro-bibenzyls and 3-benzyloxy-4'-bromo-5-methoxy-,3-benzyloxy-3',4'-dichloro-5-methoxy-stilbenes were inhibitory,and 4'-bromo-3-nitrostilbene was promotive at a concentrationof 100 mg/liter. The results obtained by the other bioassayswere qualitatively consistent with these findings, although3-amino-4'- chlorobibenzyl and 4'-bromo-3-nitrostilbene werenot tested in all the bioassays. In the seed germination, which was rather tolerant to the testanalogues, batatasin III was inactive but 3-benzyloxy-4'-bromo-5-methoxy-and 3-benzyloxy-3',4'-dichloro- 5-methoxystilbenes were veryactive. Thus, if substituted properly, bibenzyls and stilbenes are activewithout hydroxyl and methoxyl group(s) as the functional group.
3 Present address: The National Institute for EnvironmentalStudies, Yatabc, Ibaraki 300-21, Japan. (Received November 19, 1975; ) 相似文献
46.
It was reported previously that two spherical flacherie viruses of silkworm, FVS I and FVS II, had been isolated from flacherie silkworm larvae and the nucleic acid of FVS II was RNA as suggested by the experiments of incorporation of [3H]-uracil. In this paper, it has been confirmed by biochemical methods that the nucleic acid of FVS I and FVS II is RNA. FVS I and FVS II were labeled with 32P in flacherie silkworms, and the viruses were analyzed by sucrose density gradient centrifugation. When the 32P-labeled compound in the viruses was treated with 0.5 n KOH, the acid-insoluble 32P-labeled compound changed to acid-soluble compounds. It was determined by paper chromatography and ion-exchange column chromatography that the alkali-decomposed compounds included four ribonucleotides. Therefore, the viral nucleic acid of FVS I and FVS II was determined to be RNA. The correlations between FVS I and FVS II particles were discussed, and it was suggested that FVS I and FVS II might be closely related or were the same viral species. 相似文献
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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
49.
Abstract 2′-Deoxy-2-(p-nitrophenyl)-adenosine (.15) was found to be the most potent mutagen when tested with S. typhimurium TA 98 and TA 100 in the series of compounds, whose activity towards TA 98 is one order of magnitude greater than that of 4-nitroquinoline N-oxide. In another series of reactions, synthesis of 2-alkynyl-adenosines (18) was achieved through the palladium catalyzed cross-coupling of terminal alkynes with 2-iodoadenosine (17). Compounds bearing the 2-C[dbnd]CCH(R)OH side-chain exhibited potent antiallergic activity in rats. These compounds, however, possessed hypotensive activity accompanied by a decrease in heart rate whereas with a longer alkyl side-chain at the 2-position, compounds showed selective hypotensive activity. 相似文献
50.
Akiko Kusunoki Akira Wada Naoko Kurosaki Tohru Kimura Kazuyuki Takai Naoki Yamamoto 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1705-1708
Abstract CXCR4 is both a chemokine receptor and an entry co-receptor for the T-cell line-adapted human immunodeficiency virus type 1 (HIV-1). To find a more efficacious therapeutic treatement of acquied immunodeficiency syndrome, we exmined the effects of antisense oligonucleotides on CXCR4 production. COS cells, stably expressing CXCR4 and CD4, were incubated with several kinds of oligonucleotides. Total human p24 antigen production was determined using an enzyme-linked immunosorbent assay system. An antisense phosphorothioate-modified oligonucleotide, complementary to the translation region of the CXCR4 mRNA, showed minimal inhibition of p24 antigen production at the high concentration of 2μM. On the other hand, the antisense phosphorothioate oligonucleotide, when used with transfection reagents, showed high efficiency at low concentrations, and confirmed the sequence-specific action. Interestingly, the oligonucleotide with the natual phosphodiester backbone, when used with the transfection reagents, also had high functional effects, comparable to the modified oligonucleotide. This defines the prerequisite criteria necessary for the design and the application of antisense oligonucleotides against HIV-1 in vivo. 相似文献