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31.
Ikeda Y Yonemitsu Y Kataoka C Kitamoto S Yamaoka T Nishida K Takeshita A Egashira K Sueishi K 《American journal of physiology. Heart and circulatory physiology》2002,283(5):H2021-H2028
Monocyte/macrophage chemoattractant protein-1 (MCP-1), a potent chemoattractant chemokine and an activator for mononuclear cells, may play a role in the initiation and/or progression of pulmonary hypertension (PH). To determine whether blockade of a systemic MCP-1 signal pathway in vivo may prevent PH, we intramuscularly transduced a naked plasmid encoding a 7-NH(2) terminus-deleted dominant negative inhibitor of the MCP-1 (7ND MCP-1) gene in monocrotaline-induced PH. We also simultaneously gave a duplicate transfection at 2-wk intervals or skeletal muscle-directed in vivo electroporation (EP) to evaluate whether a longer or higher expression might be more effective. The intramuscular reporter gene expression was enhanced 10 times over that by EP than by simple injection, and a significant 7ND MCP-1 protein in plasma was detected only in the EP group. 7ND MCP-1 gene transfer significantly inhibited the progression of MCT-induced PH as evaluated by right ventricular systolic pressure, right ventricular hypertrophy, medial hypertrophy of pulmonary arterioles, and mononuclear cell infiltration into the lung. Differential effects of longer or higher transgene expression were not apparent. Although the in vivo kinetics of 7ND MCP-1 gene therapy should be studied further, these encouraging results suggest that an anti-inflammatory strategy via blockade of the MCP-1 signal pathway may be an alternative approach to treat subjects with PH. 相似文献
32.
Tryptensin, a vasopressor substance generated from human plasma protein fraction IV-4 by trypsin, has been isolated and the amino acid composition analysed. The procedures used for the isolation were: (a) adsorption of the formed tryptensin on Dowex 50W (X2; NH4+ form); (b) gel filtration through Sephadex G-25; (c) cation-exchange chromatography on CM-cellulose; (d) anion-exchange chromatography on DEAE-cellulose; (e) re-chromatography on CM-cellulose; (f) gel filtration on Bio-Gel P-2; (g) partition chromatography on high-pressure liquid chromatography. The homogeneity of the isolated tryptensin was confirmed by thin-layer chromatography and thin-layer electrophoresis. The amino acid analysis of the hydrolysate suggested the following proportional composition: Asp, 1; Val, 1; Ile, 1; Tyr, 1; Phe, 1; His, 1; Arg, 1; Pro, 1. This composition is identical with that of human angiotensin. 相似文献
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Maiko Matsushita Yohei Otsuka Naoya Tsutsumida Chiaki Tanaka Akane Uchiumi Koji Ozawa Takuma Suzuki Daiju Ichikawa Hiroyuki Aburatani Shinichiro Okamoto Yutaka Kawakami Yutaka Hattori 《PloS one》2016,11(1)
The homeobox protein, PEPP2 (RHOXF2), has been suggested as a cancer/testis (CT) antigen based on its expression pattern. However, the peptide epitope of PEPP2 that is recognized by cytotoxic T cells (CTLs) is unknown. In this study, we revealed that PEPP2 gene was highly expressed in myeloid leukemia cells and some other hematological malignancies. This gene was also expressed in leukemic stem-like cells. We next identified the first reported epitope peptide (PEPP2271-279). The CTLs induced by PEPP2271-279 recognized PEPP2-positive target cells in an HLA-A*24:02-restricted manner. We also found that a demethylating agent, 5-aza-2’-deoxycytidine, could enhance PEPP2 expression in leukemia cells but not in blood mononuclear cells from healthy donors. The cytotoxic activity of anti-PEPP2 CTL against leukemic cells treated with 5-aza-2’-deoxycytidine was higher than that directed against untreated cells. These results suggest a clinical rationale that combined treatment with this novel antigen-specific immunotherapy together with demethylating agents might be effective in therapy-resistant myeloid leukemia patients. 相似文献
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Yoko Marutani Yasuo Yamauchi Mari Higashiyama Akihito Miyoshi Seiji Akimoto Kanako Inoue Ken-ichi Ikeda Masaharu Mizutani Yukihiro Sugimoto 《Photosynthesis research》2017,131(1):41-50
Light and temperature affect state transitions through changes in the plastoquinone (PQ) redox state in photosynthetic organisms. We demonstrated that light and/or heat treatment induced preferential photosystem (PS) I excitation by binding light-harvesting complex II (LHCII) proteins. The photosystem of wheat was in state 1 after dark overnight treatment, wherein PQ was oxidized and most of LHCII was not bound to PSI. At the onset of the light treatment [25 °C in the light (100 µmol photons m?2 s?1)], two major LHCIIs, Lhcb1 and Lhcb2 were phosphorylated, and the PSI–LHCII supercomplex formed within 5 min, which coincided with an increase in the PQ oxidation rate. Heat treatment at 40 °C of light-adapted wheat led to further LHCII protein phosphorylation of, resultant cyclic electron flow promotion, which was accompanied by ultrafast excitation of PSI and structural changes of thylakoid membranes, thereby protecting PSII from heat damage. These results suggest that LHCIIs are required for the functionality of wheat plant PSI, as it keeps PQ oxidized by regulating photochemical electron flow, thereby helping acclimation to environmental changes. 相似文献
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Hideo Hasegawa Hiroshi Sato Shiho Fujita Pierre Philippe Mbehang Nguema Kenichi Nobusue Kei Miyagi Takanori Kooriyama Yuji Takenoshita Shohei Noda Akiko Sato Azusa Morimoto Yatsukaho Ikeda Toshisada Nishida 《Parasitology international》2010,59(3):407-413
In order to identify the causative agent of imported strongyloidiasis found in a Japanese mammalogist, who participated in a field survey in Tanzania, the hyper-variable region IV (HVR-IV) of 18S ribosomal DNA and partial mitochondrial cytochrome c-oxidase subunit 1 gene (cox1) were analyzed and compared with Strongyloides fuelleborni collected from apes and monkeys of Africa and Japan, and S. stercoralis from humans, apes and dogs. The HVR-IV and cox1 of the patient's worms were identical to or only slightly differed from those of worms parasitic in Tanzanian chimpanzees and yellow baboons, demonstrating that the patient acquired the infection during her field survey in Tanzania. Phylogenetic analysis with the maximum-likelihood method largely divided isolates of S. fuelleborni into three groups, which corresponded to geographical localities but not to host species. Meanwhile, isolates of S. stercoralis were grouped by the phylogenetic analysis into dog-parasitic and primate-parasitic clades, and not to geographical regions. It is surmised that subspeciation has occurred in S. fuelleborni during the dispersal of primates in Africa and Asia, while worldwide dispersal of S. stercoralis seems to have occurred more recently by migration and the activities of modern humans. 相似文献
39.
Yoshio Kawahara Yasuhiko Yoshihara Shigeho Ikeda Hiroe Yoshii Yoshio Hirose 《Applied microbiology and biotechnology》1990,34(1):87-90
Summary The growth rate, sugar consumption rate, and production rate of an l-lysine producing Brevibacterium lactofermentum mutant were stimulated by addition of exogenous glycine betaine. Glycine betaine stimulated the growth rate especially in media of inhibitory osmotic stress, and the stimulation was independent of any specific solute. Therefore growth stimulation by glycine betaine was considered to be an osmoprotective effect. A strong enhancement of the sugar consumption rate and the l-lysine production rate was observed even with resting cells under osmotic stress as well as in a fermentation with growing cells. These data indicated that the osmoprotective effects of glycine betaine on l-lysine production can be independent of protein synthesis.
Offprint requests to: Yoshio Kawahara 相似文献
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