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121.
Hiroki Tsumoto Syo Kawahara Yuki Fujisawa Takayoshi Suzuki Hidehiko Nakagawa Kohfuku Kohda Naoki Miyata 《Bioorganic & medicinal chemistry letters》2010,20(6):1948-1952
Water-soluble [60]fullerene (C60) derivatives were synthesized to examine their bioactivities. PC12 cells were used as a model of nerve cells and the bioactivities of synthesized C60 derivatives together with some reported ones were tested. Among the compounds tested, C60/(γ-CyD)2, C60-bis(γ-CyD) (5) containing C60-mono(γ-CyD) (5′), and C60/PVP were sufficiently soluble in water and showed an enhancing effect on the neurite outgrowth of NGF-treated PC12 cells. 相似文献
122.
Hirata S Matsuyoshi H Fukuma D Kurisaki A Uemura Y Nishimura Y Senju S 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(2):918-925
We previously reported the protection from myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) by the adoptive transfer of genetically modified embryonic stem cell-derived dendritic cells (ES-DC) presenting MOG peptide in the context of MHC class II molecules and simultaneously expressing TRAIL (ES-DC-TRAIL/MOG). In the present study, we found the severity of EAE induced by another myelin autoantigen, myelin basic protein, was also decreased after treatment with ES-DC-TRAIL/MOG. This preventive effect diminished, if the function of CD4(+)CD25(+) regulatory T cells (Treg) was abrogated by the injection of anti-CD25 mAb into mice before treatment with ES-DC-TRAIL/MOG. The adoptive transfer of CD4(+)CD25(+) T cells from ES-DC-TRAIL/MOG-treated mice protected the recipient mice from MOG- or myelin basic protein-induced EAE. The number of Foxp3(+) cells increased in the spinal cords of mice treated with ES-DC-TRAIL/MOG. In vitro experiments showed that TRAIL expressed in genetically modified ES-DC and also in LPS-stimulated splenic macrophages had a capacity to augment the proliferation of CD4(+)CD25(+) T cells. These results suggest that the prevention of EAE by treatment with ES-DC-TRAIL/MOG is mediated, at least in part, by MOG-reactive CD4(+)CD25(+) Treg propagated by ES-DC-TRAIL/MOG. For the treatment of organ-specific autoimmune diseases, induction of Treg reactive to the organ-specific autoantigens by the transfer of DC-presenting Ags and simultaneously overexpressing TRAIL therefore appears to be a promising strategy. 相似文献
123.
Gasparin G Miyata M Coutinho LL Martinez ML Teodoro RL Furlong J Machado MA Silva MV Sonstegard TS Regitano LC 《Animal genetics》2007,38(5):453-459
Differences in domestication and selection processes have contributed to considerable phenotypic and genotypic differences between Bos taurus and Bos indicus cattle breeds. Of particular interest in tropical and subtropical production environments are those genetic differences between subspecies that underlie the phenotypic extremes in tolerance and susceptibility to parasite infection. In general, B. taurus cattle are more susceptible to ectoparasites than B. indicus cattle in tropical environments, and much of this difference is under genetic control. To identify genomic regions involved in tick resistance, we developed a B. taurus x B. indicus F(2) experimental population to map quantitative trait loci (QTL) for resistance to the Riphicephalus (Boophilus) microplus tick. About 300 individuals were measured for parasite load in two seasons (rainy and dry) and genotyped for 23 microsatellite markers covering chromosomes 5, 7 and 14. We mapped a suggestive chromosome-wide QTL for tick load in the rainy season (P < 0.05) on chromosome 5. For the dry season, suggestive (P < 0.10) chromosome-wide QTL were mapped on chromosomes 7 and 14. The additive effect of the QTL on chromosome 14 corresponds to 3.18% of the total observed phenotypic variance. Our QTL-mapping study has identified different genomic regions controlling tick resistance; these QTL were dependent upon the season in which the ticks were counted, suggesting that the QTL in question may depend on environmental factors. 相似文献
124.
125.
Oxidative stress affecting lipid membranes is considered to be closely related to cardiovascular disease and brain ischemia. In this study, we designed and synthesized membrane-localizing TEMPO derivatives and demonstrated that one of these synthesized probes, compound 1, localized and detected oxidative stress in the cell membrane in an endotoxic model of a mouse macrophage-like cell line. Compound 1 is therefore a potentially useful probe for evaluating oxidative stress at the cell membrane. 相似文献
126.
Yamada H Tamada T Kosaka M Miyata K Fujiki S Tano M Moriya M Yamanishi M Honjo E Tada H Ino T Yamaguchi H Futami J Seno M Nomoto T Hirata T Yoshimura M Kuroki R 《Protein science : a publication of the Protein Society》2007,16(7):1389-1397
A protein crystal lattice consists of surface contact regions, where the interactions of specific groups play a key role in stabilizing the regular arrangement of the protein molecules. In an attempt to control protein incorporation in a crystal lattice, a leucine zipper-like hydrophobic interface (comprising four leucine residues) was introduced into a helical region (helix 2) of the human pancreatic ribonuclease 1 (RNase 1) that was predicted to form a suitable crystallization interface. Although crystallization of wild-type RNase 1 has not yet been reported, the RNase 1 mutant having four leucines (4L-RNase 1) was successfully crystallized under several different conditions. The crystal structures were subsequently determined by X-ray crystallography by molecular replacement using the structure of bovine RNase A. The overall structure of 4L-RNase 1 is quite similar to that of the bovine RNase A, and the introduced leucine residues formed the designed crystal interface. To characterize the role of the introduced leucine residues in crystallization of RNase 1 further, the number of leucines was reduced to three or two (3L- and 2L-RNase 1, respectively). Both mutants crystallized and a similar hydrophobic interface as in 4L-RNase 1 was observed. A related approach to engineer crystal contacts at helix 3 of RNase 1 (N4L-RNase 1) was also evaluated. N4L-RNase 1 also successfully crystallized and formed the expected hydrophobic packing interface. These results suggest that appropriate introduction of a leucine zipper-like hydrophobic interface can promote intermolecular symmetry for more efficient protein crystallization in crystal lattice engineering efforts. 相似文献
127.
128.
Design, synthesis, and biological activity of folate receptor-targeted prodrugs of thiolate histone deacetylase inhibitors 总被引:1,自引:0,他引:1
Suzuki T Hisakawa S Itoh Y Suzuki N Takahashi K Kawahata M Yamaguchi K Nakagawa H Miyata N 《Bioorganic & medicinal chemistry letters》2007,17(15):4208-4212
Aiming to develop selective anticancer drugs, we designed and synthesized three disulfides bearing a folic acid moiety as candidate folate receptor (FR)-targeted prodrugs of thiolate histone deacetylase inhibitors. Among them, compound 1 displayed growth-inhibitory activity toward folate receptor-positive MCF-7 breast cancer cells. The activity of 1 was significantly reduced by free folic acid, suggesting that cellular uptake of 1 is mediated by FR. 相似文献
129.
Burioka N Takata M Endo M Miyata M Takeda K Chikumi H Tomita K Fukuoka Y Nakazaki H Sano H Shimizu E 《Chronobiology international》2007,24(1):183-189
This study examined whether in vivo exposure to a β2-adrenoceptor agonist, tulobuterol, induces human Period1 (hPer1) mRNA expression in cells from peripheral whole blood. In one experiment, oral tulobuterol was administered to five healthy volunteers at 22:00 h, while in another, a transdermally tulobuterol patch was applied to the same five subjects at 20:00 h. In each experiment, serum tulobuterol concentrations were measured at four time points, and total RNA was isolated from peripheral blood cells for determinations of hPer1 mRNA expression by real-time polymerase chain reaction. Both the tulobuterol tablet and the transdermal patch increased hPer1 mRNA expression, suggesting that analyses of human peripheral blood cells could reliably represent peripheral clock gene mRNA expression in vivo. 相似文献