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71.
Suplatast tosilate inhibits thymus- and activation-regulated chemokine production by antigen-specific human Th2 cells 总被引:2,自引:0,他引:2
N. Oda K. Minoguchi A. Tanaka T. Yokoe H. Minoguchi H. Matsuo M. Nakashima T. Tasaki M. Adachi 《Clinical and experimental allergy》2002,32(12):1782-1786
BACKGROUND: Suplatast tosilate is an anti-allergic agent that suppresses cytokine production by human Th2 cells. OBJECTIVE: We investigated the effects of suplatast tosilate on the production of thymus- and activation-regulated chemokine (TARC) by T cells from allergic patients with asthma. METHODS: Purified protein derivative (PPD)-specific Th1 cell lines and Dermatophagoides farinae (Der f)-specific Th2 cell lines were established from nine patients with house dust mite-allergic asthma. The effects of suplatast tosilate on mRNA expression of TARC and protein production of TARC from antigen-specific Th1 or Th2 cell lines were investigated after stimulation with relevant antigens or phytohemagglutinin (PHA). In addition, the effects of IL-4, IL-10, and IFN-gamma on TARC production by Der f-specific Th2 cell lines in the presence or absence of suplatast tosilate were studied. RESULTS: Although PPD-specific Th1 cell lines did not produce TARC after stimulation with PPD antigen or PHA, stimulation of Der f-specific Th2 cell lines with Der f antigen or PHA increased production of TARC. Suplatast tosilate significantly and dose-dependently inhibited production of TARC by Der f-specific Th2 cell lines stimulated with either Der f antigen (76.5% inhibition at 100 microg/mL, P < 0.01) or PHA (81.9% inhibition at 100 microg/mL, P < 0.01). TARC production by Der f-specific Th2 cell lines was significantly increased only by activation with IL-4 but not with IL-10 or IFN-gamma; this increase in TARC production was significantly inhibited by suplatast tosilate (97.5% inhibition at 100 microg/mL, P < 0.01). CONCLUSION: Suplatast tosilate inhibits TARC production by human Th2 cells. Therefore, this agent inhibits both Th2 cytokine and Th2 chemokine and may be a useful anti-allergic agent. 相似文献
72.
Nakashima I Kato M Akhand AA Suzuki H Takeda K Hossain K Kawamoto Y 《Antioxidants & redox signaling》2002,4(3):517-531
The signaling for activation of protein tyrosine kinases (PTKs) is usually started by binding of ligands to cell-surface receptors. However, recent evidence suggests the presence of ligand binding-independent signaling pathways that are mediated by oxidative stress. Oxidation and reduction of protein cysteine sulfhydryl (SH) groups may work as a molecular switch to start or to stop the signaling. It is known that oxidation of cysteine SH groups on protein tyrosine phosphatases switches off the action of protein tyrosine phosphatases. This event may not, however, signal for initial autophosphorylation of previously unphosphorylated PTKs, whereas it certainly prevents dephosphorylation of once-phosphorylated PTKs. We have suggested new mechanisms for oxidative stress-mediated PTK activation. First, cell-surface glycosylphosphatidylinositol-anchoring proteins and a phosphoglycolipid/cholesterol-enriched membrane microdomain termed a "raft" can be the direct targets of oxidative stress for inducing their clustering through an S-S-bonded or S-X-S-bonded crosslinking of cell-surface proteins and subsequent activation of raft-associating Src family PTKs. Second, intracellular specific cysteine SH groups on PTK proteins can be another target of oxidative stress for inducing a conformational change necessary for initial activation of PTKs. A possible relationship between cell-surface and intracellular events is that the former frequently induces superoxide production as the second messenger for the latter. 相似文献
73.
MML(Medical Markup Language)是一套不同医疗设施间的数据交换规格。于1995年在日本被开发。MML从版本2.21开始使用XML(eXtensible Markup Language)作为标记语言。而最新版本3.0又遵循HL7Clincal Document Architecture(CDA),包含14模块和36个数据定义表格。目前在中国,还没有一个使用XML来结构整个病历内容的规格。鉴于MML的柔韧性,我们制作了一个基于3.0版本的汉化版。日本与中国虽然诊疗流程、病历记录的内容等都很相似,但是也有一些,比如民族的表现、中医诊断分类,医师资格分类等都是日本不存在的或者分类不同的信息。另外,因为国情不同,医疗保险制度也完全不同。为了使MML能在中国的医院适用,我们追加和更改了12个数据定义表格,并重新制作了医疗保险信息模块。MML汉化版不止是一个对原规格的翻译和说明,它还考虑了本地的需要。因此,使用MML汉化版在中国的医疗设施间进行医疗数据交换已经成为可能。 相似文献
74.
75.
Iwata K Takamura N Nakashima M Alipov G Mine M Matsumoto N Yoshiura K Prouglo Y Sekine I Katayama I Yamashita S 《Human pathology》2004,35(4):460-464
A high incidence of skin cancers has been noted around the Semipalatinsk Nuclear Testing Site (SNTS) in Kazakhstan. Recently, basal cell carcinoma (BCC) susceptibility genes, human homolog of the Drosophila pathed gene (PTCH), and the xeroderma pigmentosa group A-complementing gene (XPA), have been cloned and localized on chromosome 9q22.3. To clarify the effect of low-dose irradiation on the occurrence of BCC, we used microdissection and polymerase chain reaction to identify loss of heterozygosity (LOH) at 9q22.3 using BCC samples obtained from this region. Ten Japanese samples were analyzed as controls. LOH with at least 1 marker was identified in 5 of 14 cases from around SNTS, whereas only 1 case with 1 marker was identified among the 10 Nagasaki cases. The total number of LOH alleles from SNTS (8 of 45) was significantly higher than the number from Nagasaki (1 of 26) (P = 0.03). The higher incidence of LOH on 9q22.3 in BCC from around SNTS suggests involvement of chronic low-dose irradiation by fallout from the test site as a factor in the cancers. 相似文献
76.
Takeshita M Okamura S Oshiro Y Imayama S Okamoto S Matsuki Y Nakashima Y Okamura T Shiratsuchi M Hayashi T Kikuchi M 《Human pathology》2004,35(2):231-239
CD56 is an important marker for prospecting clinicopathologic features of cytotoxic T-cell and natural killer (NK)/T-cell lymphomas. We examined 22 cases of subcutaneous panniculitis-like lymphoma and classified these into CD56-positive and CD56-negative groups. The 11 CD56-negative cases were mainly in the younger age group and had systemic subcutaneous nodules without ulceration. They exhibited subcutaneous invasion by medium-sized lymphoma cells, scattered erythrophagocytosis, patchy necrosis, and little tumor invasion in the superficial dermis. Their lymphoma cells had characteristics of CD3 epsilon-, CD8-, TcR beta F1-, T-cell intracellular antigen (TIA)1-, and granenzyme B-positive cytotoxic T cells and were negative for apoptosis-promoting proteins CD95 (Fas), Bax, CPP32 (caspase 3), and p53 (DO7). Ten patients were alive despite clinical signs of hemophagocytic syndrome and relapses in 7 cases. The 11 CD56-positive cases had systemic ulcerative skin tumors composed of pleomorphic lymphoma cells with massive necrosis and little erythrophagocytosis involving the subcutis and also often the whole dermis. Their tumor cells were positive for CD3 epsilon, TIA1, granenzyme B, CD95, CD95L (Fas ligand), Bax, and CPP32. Three cases were of the TcR beta F1-positive phenotype, 1 was of the TcR gamma/delta-positive T-cell phenotype, and 6 were of the TcR beta F1- and TcR gamma/delta-negative NK/T-cell phenotype. Six cases were p53 (DO7) positive. Seven cases had complications of liver dysfunction and cytopenia, and 8 died of disease. One CD56-negative case and 3 CD56-positive cases had nuclear signals of Epstein-Barr virus-encoded RNA in their lymphoma cells. The 2 groups had significantly (P <0.01) different prognoses by Kaplan-Meier and log-rank methods. Patients with CD56-negative and CD56-positive groups had statistically different clinicopathologic, immunohistologic, and functional findings and prognoses. 相似文献
77.
Non-specific stimulation of immunoglobulin synthesis in mice by capsular polysaccharide of Klebsiella pneumoniae 总被引:7,自引:1,他引:7
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Intramuscular injection of a non-immunogenic dose (1 mg) of the capsular polysaccharide of Klebsiella pneumoniae (CPS-K) into mice caused a marked and prolonged increase in the amount of the serum IgM and IgG. The increase of IgM after this injection was over 100 times greater than that of antigen-specific IgM antibodies produced by injection of an immunogenic dose of CPS-K (5 μg) or sheep red blood cells (SRBC) (2 X 108). The increase in the amount of immunoglobulins was not related to induction of immunological paralysis to the major subcomponent of CPS-K (acidic CPS-K) by a large dose of antigen, but was induced by non-antigenic stimulation by the minor subcomponent of CPS-K (neutral CPS-K), which was non-immunogenic at any dose. In mice injected with a non-immunogenic dose of CPS-K, antibody levels in the serum to three kinds of non-cross-reacting antigens, SRBC, bovine serum albumin (BSA) and a possibly autochthonous IgG (IgM—IgG mixed type cryoglobulin) were also increased. The number of plaque-forming cells (PFC) for SRBC in the spleens of mice was also markedly increased after CPS-K injection. These antibodies to SRBC and BSA and PFC for SRBC were exclusively of IgM type and increased to as high levels as those found after specific antigenic stimulation. This marked increase in IgM antibody was neither followed by an increase in IgG antibody nor by immunological memory for a secondary IgG response. 相似文献
78.
Sun Y Wada M Al-Dirbashi O Kuroda N Nakazawa H Nakashima K 《Journal of chromatography. B, Biomedical sciences and applications》2000,749(1):49-56
A highly sensitive and selective high-performance liquid chromatographic method with peroxyoxalate chemiluminescence detection for the determination of bisphenol A at sub-ppb levels is described. Bisphenol A was derivatized with 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride and the excess unreacted reagent was removed by a simple solid-phase extraction procedure with recoveries of approximately 60%. The separation was carried out isocratically on an ODS column and the derivatized bisphenol A was detected by peroxyoxalate chemiluminescence. A mixture of bis[2-(3,6,9-trioxadecanyloxycarbonyl)-4-nitrophenyl]oxalate (0.6 mM) and hydrogen peroxide (25.0 mM) dissolved in acetonitrile was used as a chemiluminescence reagent solution with a mixture of imidazole-HNO3 buffer (40.0 mM, pH 7.0): acetonitrile (17:83, v/v) as a mobile phase. The linear standard curve was obtained over the range from 0.57 (2.5) to 22.8 (100) ppb (nM) (r=0.996) with a detection limit of 0.38 ppb (2.8 fmol on column) at a signal-to-noise ratio of 3. The method was successfully applied to the determination of bisphenol A in hot water in contact with commercially available baby bottle samples. 相似文献
79.
Nakashima E Mabuchi A Kashimada K Onishi T Zhang J Ohashi H Nishimura G Ikegawa S 《American journal of medical genetics. Part A》2003,(3):253-256
We examined 12 Japanese patients with metaphyseal chondrodysplasia (MCD) for mutations in the ribonuclease mitochondrial RNA processing gene (RMRP), and identified four novel mutations in two patients with typical and atypical cartilage-hair hypoplasia (CHH), a form of MCD characterized by extra-skeletal manifestations including hypoplastic hair and defective immunity. A patient with typical CHH had a 17-bp duplication at +3 and a de novo 182G > A. The other patient with atypical CHH had a 17-bp insertion at -20 and a 218A > G. Expression analysis revealed that the allele with this insertion mutation in the promoter region silenced the gene. Spectrum analysis of the mutations and polymorphisms in RMRP showed marked difference between the Japanese and other ethnic groups. Such ethnic and phenotypic difference should be taken into account in mutation analysis of the gene. 相似文献
80.
Y. Shimada K. Nakashima Y. Fujiwara T. Komatsu M. Kawanishi J. Takezawa S. Takatani 《Medical & biological engineering & computing》1991,29(5):557-561
The design of a noninvasive reflectance pulse oximeter that uses the same principle of transmittance pulse oximeter and analyses the oxygen saturation of arterial blood was described. Four sets of red and infra-red LEDs were used as light sources. The respective reflectance photoelectric outputs were used to make an internal calibration curve of the instrument relative to the arterial oxygen saturation values measured with a Co-Oximeter (OSM-3) in five healthy nonsmoking subjects during steady-state hypoxaemia. The accuracy of the present instrument was studied in six patients with respiratory failure. From 22 samples, a good correlation coefficient (0.98) with a standard deviation of 1.42 was obtained in the range between 73 and 100 per cent between the arterial oxygen saturation measured with the present instrument and that with the Co-Oximeter. The result strongly suggests the usefulness of this oximeter in monitoring patients with hypoxaemia. 相似文献