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51.
Komatsu H Awano H Tanikawa H Itou K Ikeda I 《Nucleosides, nucleotides & nucleic acids》2001,20(4-7):1291-1293
A chemical synthesis of 2-deoxyribose-1-phosphate 2 and its enzymatic conversion into purine 2'-deoxynucleosides (dNus) are shown. Besides the chemo-enzymatic process for purine dNus, a modified process for practical dC preparation is also established. Consequently, a series of practical manufacturing processes of all four dNus have been realized via novel strategies. 相似文献
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Ikeda E Yagi K Kojima M Yagyuu T Ohshima A Sobajima S Tadokoro M Katsube Y Isoda K Kondoh M Kawase M Go MJ Adachi H Yokota Y Kirita T Ohgushi H 《Differentiation; research in biological diversity》2008,76(5):495-505
Abstract Adult stem cells have been reported to exist in various tissues. The isolation of high-quality human stem cells that can be used for regeneration of fatal deseases from accessible resources is an important advance in stem cell research. In the present study, we identified a novel stem cell, which we named tooth germ progenitor cells (TGPCs), from discarded third molar, commonly called as wisdom teeth. We demonstrated the characterization and distinctiveness of the TGPCs, and found that TGPCs showed high proliferation activity and capability to differentiate in vitro into cells of three germ layers including osteoblasts, neural cells, and hepatocytes. TGPCs were examined by the transplantation into a carbon tetrachloride (CCl4 )-treated liver injured rat to determine whether this novel cell source might be useful for cell-based therapy to treat liver diseases. The successful engraftment of the TGPCs was demonstrated by PKH26 fluorescence in the recipient's rat as to liver at 4 weeks after transplantation. The TGPCs prevented the progression of liver fibrosis in the liver of CCl4 -treated rats and contributed to the restoration of liver function, as assessed by the measurement of hepatic serum markers aspartate aminotransferase and alanine aminotransferase. Furthermore, the liver functions, observed by the levels of serum bilirubin and albumin, appeared to be improved following transplantation of TGPCs. These findings suggest that multipotent TGPCs are one of the candidates for cell-based therapy to treat liver diseases and offer unprecedented opportunities for developing therapies in treating tissue repair and regeneration. 相似文献
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Jayawardana ST Ushio H Niyonsaba F Gondokaryono SP Takenaka H Ikeda S Okumura K Ogawa H 《Biochemical and biophysical research communications》2008,365(1):137-142
The apoptosis of bone marrow-derived mast-cells (BMMCs) after growth factor withdrawal was significantly prevented by a high concentration of IgE in the absence of antigen, and further enhanced by the presence of Toll-like receptor4 (TLR4) ligand, lipopolysaccharide (LPS). The effect of LPS was mediated by TLR4, since TLR4-deficient BMMCs did not show synergistic effects with IgE. The neutralizing amount of anti-IL-3 did not reverse the anti-apoptotic effects of both IgE and combination with LPS. LPS treatment with monomeric IgE synergistically prevented the loss of mitochondrial membrane potentials and was associated with an enhanced expression of anti-apoptotic protein, Bcl-xL, or with a reduced expression of proapoptotic protein, Puma, and Bim, respectively. Altogether, these results suggest that LPS, in a TLR4-dependent manner, together with IgE, synergistically prevent mast-cell apoptosis and may contribute to regulate the tissue mast-cell number. 相似文献
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Published data on the biomass and specific respiration ratesof mesozooplankton in the oceans across all latitudes were combinedto assess their community respiration on a global basis. Mesozooplanktonbiomass was higher in boreal/anti-boreal and polar waters, intermediatein equatorial waters and lowest in the subtropical gyres. Specificrespiration rates were the highest in equatorial waters anddecreased rapidly poleward. Global community respiration ofmesozooplankton in the upper 200 m of the oceans integratedover all latitudes was 10.4 ± 3.7 (SE) Gt C year1(n = 838). Below the epipelagic zone, mesozooplankton respirationliving in the mesopelagic (2001000 m) and bathypelagic(below 1000 m) zones was estimated as 2.2 ± 0.4 (n =57) and 0.40 ± 0.2 (n = 12) Gt C year1, respectively.Thus, global depth-integrated mesozooplankton respiration was13.0 ± 4.2 Gt C year1 (1732% of globalprimary production), which is 38-fold higher than thevalues assigned to mesozooplankton respiration in recent estimatesof total respiration in the ocean. Thus, it appears that mesozooplanktonrepresent a major, but neglected component of the carbon cyclein the ocean. 相似文献
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Sueyoshi Kuni; Kubo Yoshihiro; Yamagishi Kenji; Ogura Nagao; Ochiai Kuniyasu; Fukushima Kazuo; Ikeda Tadashi; Nakagawa Hiroki 《Plant & cell physiology》1988,29(6):975-980
Two monoclonal antibodies, 17(3)9 and 36(79)4, were preparedagainst nitrate reductase from Spinacia oleracea L. leaves.An enzyme-linked immunosorbent assay showed that 17(3)9, butnot 36(79)4, reacted more strongly to heat-denatured than nativeantigen. These antibodies inhibited NADH-nitrate reductase aswell as its various partial activities including reduced methylvilogen-nitrate reductase, reduced flavin mononucleotide-nitratereductase and NADH-cytochrome c reductase activities, but notNADH-ferricyanide reductase activity. Immunoblotting after electrophoreticseparation of nitrate reductase fragments obtained by Staphyrococcusaureus V8 protease digestion of native enzyme revealed thatthe two monoclonal antibodies bind to different epitopes locatedon the 28 kDa of the NADH-ferricyanide reductase domain. (Received October 2, 1987; Accepted June 9, 1988) 相似文献