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101.
Characterization and expression of cDNA encoding coproporphyrinogen oxidase from a patient with hereditary coproporphyria 总被引:2,自引:1,他引:2
Fujita Hiroyoshi; Kondo Masao; Taketani Shigeru; Nomura Nakao; Furuyama Kazumichi; Akagi Relko; Nagai Tadashi; Terajima Masanori; Galbraith Richard A.; Sassa Shigeru 《Human molecular genetics》1994,3(10):1807-1810
Hereditary coproporphyria (HCP) is an acute hepatic porphyriawith autosomal dominant inheritance, but with a variable degreeof clinical expression. Molecular cloning, sequencing and expressionof the defective gene for coproporphyrinogen oxidase (CPO) ina patient with HCP were carried out. Enzyme assays revealedthat CPO activity in EBV-transformed lymphoblastoid cells fromthe proband and one of her sisters was 相似文献
102.
IgG inhibits the increase of platelet-associated C3 stimulated by anti-platelet antibodies 总被引:1,自引:0,他引:1
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S. Nomura Y. Miyazaki T. Miyake K. Yamaguchi H. Kido T. Kawakatsu T. Fukuroi H. Kagawa M. Suzuki M. Yanabu T. Kokawa 《Clinical and experimental immunology》1993,93(3):452-455
We investigated the increase of platelet-associated IgG and complement component 3 (C3) caused by the in vitro action of anti-platelet MoAbs, and the effect of mouse and human IgG on these events. Anti-glycoprotein IIb/IIIa and anti-glycoprotein Ib MoAbs caused a slight increase of C3, but not of platelet-associated IgG. In contrast, anti-CD9 and anti-Fcγ II receptor MoAbs caused an increase of both platelet-associated C3 and IgG. In particular, three MoAbs which activated the complement system caused a marked increase of C3. When platelet-rich plasma was treated with aspirin and prostaglandin E1 before incubation with antibodies, the increase of platelet-associated IgG was inhibited in all cases. In contrast, the increase of platelet-associated C3 was scarcely influenced. These results suggest that the binding to platelets of platelet-activating antibodies caused the increase expression of IgG molecules on the platelet surface and a possible increase of platelet-associated IgG. However, the increase of platelet-associated C3 appeared to depend on specific characteristics of the antibodies tested, such as a complement-activating effect. In addition, intact mouse or human IgG inhibited the increase of platelet-associated C3 caused by complement-activating antibodies, while F(ab')2 mouse or human IgG had no such effect. This suggested that the Fc portion of IgG may block the increase of C3 mediated by anti-platelet antibodies. 相似文献
103.
Normal human skin, malignant melanoma, nevocellular nevus, blue nevus, nevus of Ota and mongolian spot were immunohistochemically investigated on the localization of S-100 protein and neuron specific enolase (NSE). Tissues were fixed with buffered-formalin, processed with routine procedure and examined by the ABC technique. All cases of malignant melanoma and nevocellular nevus showed a relatively high amount of S-100 protein, but NSE was scantly demonstrated on about the half cases of these tumors. Blue nevus, nevus of Ota and mongolian spot revealed the presence of a small amount of S-100 protein and NSE on the half cases. Normal melanocytes were devoid of S-100 protein and NSE. Our results suggest that S-100 protein is the useful marker for diagnosis of malignant melanoma, and immunoreactive intensity for S-100 protein represents the differentiation of neural crest derived melanogenic cells and tumors. 相似文献
104.
A convenient serum-free fibrin clot culture system for murine megakaryocyte progenitor cells was developed. The culture and counting of colonies is much easier in this system, when compared with previously reported serum-free culture methods. Recombinant murine interleukin-3 (rmIL-3) stimulated megakaryocyte colony formation in a dose-dependent manner in this system. While recombinant human granulocyte colony-stimulating factor (rhG-CSF) had no effect on megakaryocytopoiesis, recombinant human erythropoietin (rhEpo) and recombinant human interleukin-6 (rhIL-6) augmented megakaryocyte colony formation stimulated by rmIL-3. The depletion of adherent cells and T cells from the cultured bone marrow did not eliminate the synergistic effect of rhEpo and rhIL-6. 相似文献
105.
106.
Morishima Y Ishii Y Kimura T Shibuya A Shibuya K Hegab AE Iizuka T Kiwamoto T Matsuno Y Sakamoto T Nomura A Taniguchi M Sekizawa K 《European journal of immunology》2005,35(10):2803-2814
To clarify the essential role of NKT cells in allergy, we investigated the contribution of NKT cells to the pathogenesis of eosinophilic airway inflammation using alpha-galactosylceramide (alpha-GalCer), a selective ligand for NKT cells. Although continuous administration of alpha-GalCer during ovalbumin (OVA) sensitization increased OVA-specific IgE levels and worsened eosinophil inflammation, a single administration of alpha-GalCer at the time of OVA challenge completely prevented eosinophilic infiltration in wild-type mice. This inhibitory effect of alpha-GalCer was associated with a decrease in airway hyperresponsiveness, an increase in IFN-gamma, and decreases in IL-4, IL-5 and IL-13 levels in the bronchoalveolar lavage fluids. Analysis of lung lymphocytes revealed that production of IFN-gamma increased in NK cells, but not in T or NKT cells, following alpha-GalCer administration. Induction of vascular cell adhesion molecule-1 in the lungs of wild-type mice was also significantly attenuated by treatment with alpha-GalCer. These effects of alpha-GalCer were abrogated in J alpha281-/- mice, which lack NKT cells, and in wild-type mice treated with anti-IFN-gamma Ab. Hence, our data indicate that alpha-GalCer suppresses allergen-induced eosinophilic airway inflammation, possibly by inducing a Th1 bias that results in inhibition of eosinophil adhesion to the lung vessels. 相似文献
107.
Lectin binding was cytofluorometrically measured on fractionated keratinocytes of guinea pig. Free keratinocytes were obtained by treatment of EDTA and trypsin. After the treatment, they were separated into 3 fractions by centrifugation on a continuous colloidal silica (Percoll) density gradient. Cells in each fraction were stained by biotinyl lectins and avidin-FITC, and fluorescence intensity was measured by cytofluorometry. Results obtained indicate that little cell surface glycoconjugate is lost during the preparation of free keratinocytes. 相似文献
108.
A multicenter prospective study on the treatment of chronic idiopathic thrombocytopenic purpura (ITP), conducted by the Idiopathic Disorders of Hematopoietic Organ Research Committee, the Ministry of Health and Welfare of Japan, is currently in progress. In this study we analyzed the clinical records of 256 patients with chronic ITP in order to define the prognostic factors. As of November, 1988 after a median observation period of 34 months, 174 of the 256 patients (68%) were alive, 11 (4%) dead and 71 (28%) lost to follow-up. Bleeding was a direct cause of death in only one patient. Assessment of the status of patients based on platelet count at the final observation revealed that 48% of patients were in remission, 21% showed improvement, and 31% remained unchanged or worsened. Univariate analyses identified 4 parameters associated with favorable prognosis: presenting platelet count less than 2 x 10(4)/microliters, platelet count greater than 10 X 10(4)/microliters after one-year follow-up, maximal platelet count greater than 10 X 10(4)/microliters during administration of the initial dose of corticosteroids and splenectomy. 相似文献
109.
Nomura M Akama KT Alves SE Korach KS Gustafsson JA Pfaff DW Ogawa S 《Neuroscience》2005,130(2):445-456
We examined the distribution of estrogen receptor (ER)-alpha and ER-beta immunoreactive (ir) cells in the dorsal (DRN) and median/paramedian (MPRN) raphe nuclei in male mice. ER-alpha ir neurons were scattered across the three subdivisions (ventral, dorsal, and lateral) of the DRN and the MPRN. Robust ER-beta ir cells were observed throughout the raphe nuclei, and were particularly abundant in the ventral and dorsal subdivisions of the DRN. Using dual-label immunocytochemistry for ER-alpha or ER-beta with tryptophan hydroxylase (TPH), the rate-limiting enzyme for 5-hydroxytryptamine (5-HT) synthesis, over 90% of ER-beta ir cells exhibited TPH-ir in all DRN subdivisions, whereas only 23% of ER-alpha ir cells contained TPH. Comparisons of ER-alpha knockout (alphaERKO) as well as ER-beta knockout (betaERKO) mice with their respective wild-type (WT) littermates revealed that gene disruption of either ER-alpha or ER-beta did not affect the other ER subtype expression in the raphe nuclei. In situ hybridization histochemistry revealed that there was a small but statistically significant decrease in TPH mRNA expression in the ventral DRN subdivision in betaERKO mice compared with betaWT mice, whereas TPH mRNA levels were not affected in alphaERKO mice. These findings support a hypothesis that ER-beta activation may contribute to the estrogenic regulation of neuroendocrine and behavioral functions, in part, by acting directly on 5-HT neurons in the raphe nuclei in male mice. 相似文献
110.
Minoru Imoto Masayoshi Kinoshita Masahiko Nishigaki 《Macromolecular chemistry and physics.》1966,94(1):238-247
The radical mutual copolymerization of p-substituted styrenes, such as p-methoxy-, p-chloro-, p-bromo-, p-cyanostyrene, and styrene was carried out with one another at 30°C. in the dark. As initiator, azobisisobutyronitrile was used. The plots of the copolymerization rates against HAMMETT 's σ values showed no linear relationships and the concave curves were obtained therefrom. The relative reactivities of p-substituted styrenes with a definite p-substituted polystyryl radical, which were shown by the reciprocal of monomer reactivity ratio r1, were plotted against σ values and concave curves were also obtained. The relative reactivities of p-substituted polystyryl radicals with p-substituted styrene were calculated from the ratios r2 and the propagation rate constants in homopolymerization. the plots of them against σ values gave straight lines with different ρ values, according to the polarity of substituents. These results suggest that polar structures in transition state affected markedly the copolymerization rates. The effect of substituents on resonance stabilization was also quantitatively estimated. 相似文献