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31.
K Oshimi Y Oshimi O Yamada M Wada T Hara H Mizoguchi 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(9):3312-3317
The role of CD3 and CD8 Ag in CD16-mediated CTL triggering was studied in TCR-alpha beta+ and TCR-gamma delta+ granular lymphocytes (GL). In TCR-alpha beta+/CD3+4-8+16+ GL obtained from patients with GL-proliferative disorders, antibody-dependent cellular cytotoxicity was inhibited by anti-CD3 and anti-CD8 mAb. Anti-CD3 mAb also inhibited antibody-dependent cellular cytotoxicity activity of TCR-gamma delta+/CD3+4-8-16+ GL from a patient and that of TCR-gamma delta+/CD3+4-8+/-16+ T cell clones established from patients with proliferating TCR-gamma delta+ GL. In TCR-gamma delta+ T cell clones, cytotoxicity against Fc gamma R+ targets was induced by stimulation of CD16 Ag with anti-CD16 mAb, and such cytotoxicity was also inhibited by anti-CD3 mAb. These results indicate that CD3 and CD8 molecules play a regulatory role in CD16-mediated CTL triggering. 相似文献
32.
33.
A hybrid protein between staphylococcal protein A and human lymphotoxin, ALT, was produced in Escherichia coli by expression of a recombinant plasmid containing the respective genes. IgG-binding activity of ALT was confirmed by Western blotting analysis and by affinity purification with IgG-Sepharose column chromatography. The purified ALT had cytotoxicity on mouse L-929 cells and its specific activity was approximately 3.5-5.0 X 10(6) U mg-1. ALT was partially degraded by a protease including in the E. coli lysate or trypsin and was converted to lymphotoxin which lacks the NH2-terminal 19 residues but possesses higher cytotoxic activity than ALT. 相似文献
34.
Kato Ryoichi; Takatsuna Sachiko; Wada Tsuyoshi; Narihara Yumi; Suzuki Takashi 《Plant & cell physiology》1996,37(5):667-672
Five-mm sections of elongation zones of Zea mesocotyls wereincubated for designated periods with various concentrationsof IAA. In vitro protein phosphorylation in the soluble fraction(85,000 x g supernatant) prepared from the sections was analyzedby sodium dodecyl sulfate-polyacrylamide gel electrophoresis.The phosphorylation of proteins in the soluble fraction thathad been prepared from sections incubated for 20 min in thepresence of 10{small tilde}s M IAA was greater than that inthe sections incubated for 20 min without IAA. The amount ofphosphorylation of proteins per protein became higher when higherconcentrations increased (10{small tilde}810{small tilde}5M).The growth of sections incubated in the presence of 10{smalltilde}8 M IAA or higher concentrations was greater than thatof sections incubated in the absence of IAA. The promotion ofgrowth by IAA was greater at higher concentrations of IAA. Proteinsin the soluble fraction, prepared from sections incubated for20 min in the presence of 10{small tilde}5 M IAA, were phosphorylatedin the presence of either 10 fM cAMP, 10 µM cGMP, 100µM W-7, 100 µM W-5, 20 µM H-7 or 20 µMHA1004. The calmodulin antagonist, W-7, and the inhibitor ofprotein kinase C, H-7, inhibited the phosphorylation of proteinsstimulated by incubation with IAA. These results suggest thatIAA promotes cell elongation via protein phosphorylation thatdepends on calmodulin-dependent protein kinase and protein kinaseC. (Received November 29, 1995; Accepted May 20, 1996) 相似文献
35.
Satoshi Sumi Kiyoshi Kidouchi Satoru Ohba Yoshiro Wada 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1995,672(2)
An automated screening system for purine and pyrimidine metabolism disorders using high-performance liquid chromatography (HPLC) with column switching is described. The system consists of a reversed-phase column, a cation-exchange column, a column switch, four sets of ultraviolet absorbance detectors, a microcomputer and other conventional equipment. As this system permits the simultaneous determination of urinary orotic acid, uracil, dihydrouracil, pseudouridine, xanthine, 2,8-dihydroxyadenine and succinyladenosine, it offers a useful method for the detection of orotic aciduria, dihydropyrimidine dehydrogenase deficiency, diphydropyrimidinuria, xanthinuria, adenine phosphoribosyltransferase deficiency and adenylosuccinase deficiency. 相似文献
36.
Kenichiro Nakashima Naotaka Kuroda Shinki Kawaguchi Mitsuhiro Wada Shuzo Akiyama 《Luminescence》1995,10(3):185-191
A sensitive peroxyoxalate chemiluminescent (PO-CL) assay for activities of oxidases (uricase, choline oxidase, cholesterol oxidase and xanthine oxidase) which catalyse a formation of hydrogen peroxide was developed using 4,4′-oxalyl-bis[(trifluoromethylsulphonyl)imino]trimethylene-bis(4-methylmorpholinium)trifluoromethanesulphonate as a chemiluminogenic reagent and 2,4,6,8-tetramorpholinopyrimido[5,4-d]pyrimidine as a fluorophore. The standard curve for hydrogen peroxide was linear over the range 1 × 10?7-1 × 10?4 mol/L. Relative standard deviations for oxidase assays were 5.1–12.7% (n = 10). Detection limits were 1 × 10?3 U/mL for uricase, 5 × 10?4 U/mL for choline oxidase, 5 × 10?3 U/mL for cholesterol oxidase and 5 × 10?4 U/mL xanthine oxidase (sample to blank ratio, 3). 相似文献
37.
Cell Sorting and Chondrogenic Aggregate Formation in Limb Bud Recombinants and in Culture 总被引:1,自引:1,他引:0
The cartilage pattern of the developing chick limb changes along the proximal-distal (PD) axis. It is assumed that these spatial changes are brought about by differences in the cellular properties of distal mesoderm, the progress zone (PZ). To examine whether these differences are actually maintained in the individual cells composing the PZ, we dissociated early (stage 20) and late (stage 25) PZ tissues into single cells, then mixed and recombined them with ectodermal jackets. The recombinants were grafted to limb bud stumps and allowed to develop into limb-like structures. Early PZ cells were distributed within whole cartilage elements along the PD axis of the limb-like structures, while cells from late PZ participated only in the formation of distal cartilage elements.
A difference in distribution pattern between the cells of early and late PZ in mixed culture was also observed. Cells of early PZ aggregated rapidly in patches and formed cartilage nodules, while the cells of late PZ distributed in regions surrounding these cell aggregates and gradually differentiated to cartilage cells. These results suggest that the cellular properties in the PZ concerning the rate of chondrogenic aggregate formation change during limb bud development, and that this change may relate to the cartilage pattern formation along the PD axis. 相似文献
A difference in distribution pattern between the cells of early and late PZ in mixed culture was also observed. Cells of early PZ aggregated rapidly in patches and formed cartilage nodules, while the cells of late PZ distributed in regions surrounding these cell aggregates and gradually differentiated to cartilage cells. These results suggest that the cellular properties in the PZ concerning the rate of chondrogenic aggregate formation change during limb bud development, and that this change may relate to the cartilage pattern formation along the PD axis. 相似文献
38.
The helicities in various fragments of bovine serum albumin (BSA) were examined in the thermal denaturation and in sodium docecyl sulfate (SDS) denaturation. The thermal denaturation was examined in a temperature range between 2 and 65°C. The helicity decreased with a rise of temperature and it recovered to some degree upon cooling temperature. A rather high reversibility was observed in the BSA fragments, which were located in the N-terminal of the parent protein and then contained the first large loop with no disulfide bridge. The high reversibility was available also for the helicity in the first large loop of the fragment, disulfide bridges of which were reduced. The fragments, which were smaller than one domain, became unstable in the SDS denaturation. The helicities of such fragments decreased in lower SDS concentrations compared with those of the intact BSA and the large fragments, which contained one or more domains. A resistance to the SDS denaturation appeared in the helices of every large loop even after the fragmentation. On the other hand, helicities of the fragments decreased to 20–25% upon the reduction of disulfide bridges. However, the helicities of these fragments increased to 35–40% in the SDS denaturation. 相似文献
39.
Seiji Ichida Tetsuyuki Wada Masahiro Sekiguchi Hiroyuki Kishino Yuko Okazaki Takafumi Akimoto 《Neurochemical research》1993,18(11):1137-1144
Characteristics of specific125I-omega-conotoxin (-CgTX) binding were systematically investigated in crude membranes from rat whole brain. Kd and Bmax Values for the binding were 49.7 pM and 181.5 fmol/mg of protein, respectively. The effects of various types of Ca channel antagonists on the binding were investigated. Dynorphin A (1–13), in particular, specifically inhibited125I--CgTX binding, but not that of [3H](+)PN200-110. Spider venom fromPlectreurys tristes did not specifically inhibit specific binding of125I--CgTX, because the venom also inhibited the binding of [3H](+)PN200-110 to a similar degree. The amount of specific binding of125I--CgTX was less in the cerebellum than that in any other area of whole brain. The cross-linker disuccinimidyl suberate did not label with125I--CgTX and its binding sites in rat whole brain, although it did in chick whole brain, which was used as a positive control. These findings suggested that dynorphine A (1–13) was a selective blocker of -CgTX-sensitive Ca channels in crude membranes from rat whole brain and that -CgTX-sensitive Ca channels were mainly present a rat brain except cerebellum. 相似文献
40.
Effects of cytoskeletal inhibitors on circular arrays of microtubules(MTs) and microfilaments (MFs) around the subapex of fern protonematawere examined. Colchicine and amiprophos-methyl disrupted arraysof MTs but not of MFs. By contrast, cytochalasin B disruptedboth MF and MT arrays, suggesting the dependence of MT arrayson MFs. (Received June 28, 1991; Accepted November 14, 1991) 相似文献