著者

鈴木 亮 中川 哲彦 水口 裕之 今津 進 中西 剛 中川 晋作 中西 真人 早川 尭夫 真弓 忠範

出版者

日本DDS学会

雑誌

Drug Delivery System (ISSN:09135006)

巻号頁・発行日

vol.13, no.2, pp.87-93, 1998-03-10 (Released:2009-01-21)

参考文献数

20

被引用文献数

1 1

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It is necessary to develop a more efficient gene expression system for gene therapy. A plasmid DNA, using eukaryoic or mammalian promoters, requires to localize into nuclear for gene expression. However, it is difficult to entry into nuclear, because nuclear pore size is not sufficient against the size of plasmid DNA. In this study, to develop a novel cytoplasmic gene expression system that dose not require nuclear localization of plasmid DNA to transcription, we examined the characterization of T7 cytoplasmic gene expression system. When co-transfected with pT7-IRES-L(luciferase expression plasmid containing T7 promoter) and T7 RNA polymerase into LLCMK2 cells, the gene expression of pT7-IRES-L was observed rapidly within 6hr after transfection and significant level of luciferase activity was detected. In contrast, pRSVL, a common plasmid DNA consist of luciferase expression plasmid and Rous sarcoma virus promoter, required 24-48hr for induction of gene expression. The gene expression level of the T7 system was enhanced with an increase in the amount of T7 RNA polymerase. To increase and prolong the gene expression, a plasmid DNA(pT7 AUTO-2) which contained the T7 RNA polymerase gene driven by the T7 promoter was co-transfected with pT7-IRES-L and T7 RNA polymerase. The plasmid DNA(pT7 AUTO-2) dose-dependently enhanced the luciferase gene expression by pT7-IRES-L and T7 RNA polymerase. In addition, we attempted to optimize the cytoplasmic gene expression system. The optimal ratio for co-transfection of pT7-IRES-L and pT7 AUTO-2 was 1 to 3 (mole ratio). These results suggest that T7 gene expression system may be useful in many gene therapies where transient but rapid efficient gene expression is required.

著者

中西 剛司 一ノ瀬 幸裕 窪 誠也

出版者

日本高圧力学会

雑誌

高圧力の科学と技術 (ISSN:0917639X)

巻号頁・発行日

vol.20, no.4, pp.377-381, 2010 (Released:2010-12-11)

参考文献数

10

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We describe a simple setup to observe H2O ice VI single crystals under high pressure by using transparent Bridgman anvils with a compact hydraulic oil cylinder. It is confirmed that growth and melting of the ice VI single crystal was clearly observed as reported in diamond anvil cell experiments. Furthermore, this setup allows students starting to learn high pressure experiments to understand the opposed anvil technique because the anvils are not only easy to manipulate but also visible even when pressure is generated.

著者

中西 剛

出版者

公益社団法人 日本薬学会

雑誌

YAKUGAKU ZASSHI (ISSN:00316903)

巻号頁・発行日

vol.127, no.3, pp.491-500, 2007 (Released:2007-03-01)

参考文献数

38

被引用文献数

2 8

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Rodent models have great utility for evaluating the potential of environmental chemicals to alter human reproductive development. However, animal studies have some problems of species differences in extrapolating to human developmental toxicity induced by xenobiotics, because the placental endocrine functions in particular vary considerably among different species. For example, estrogen biosynthesis during pregnancy in humans is much different from that in rodents. In humans, ovarian function gradually declines after fertilization, as the placenta becomes the primary site of estrogen biosynthesis during pregnancy. In contrast to the process in humans, the ovary (not the placenta) is the main source of estrogen during pregnancy in rodents, because the placenta of rodents does not express the catalytic enzymes for estrogen biosynthesis, such as aromatase. The regulation of estrogen biosynthesis in the placenta is very important for human embryos because altering placental function can cause permanent effects on embryos. It has been suggested that rodents are therefore unsuitable for evaluating the potential effects of xenobiotics on the human reproductive system and developmental toxicity induced by the alteration of placental endocrine functions. Consequently, there is an urgent need to establish effective tools to evaluate the in vivo reproductive and developmental toxicity of environmental contaminants that disrupt the placental endocrine functions, including maintenance of local estrogen concentrations in the placenta. To resolve the problems, in this review we propose using transgenic mice, in which the transgene is controlled by placental-specific promoters, and local transgene systems into the placenta using viral vectors.