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991.
目的:寻找颞叶癫痫大鼠海马组织的差异表达基因和蛋白质,以期为进一步探讨颞叶癫痫的发病机制,寻找新的治疗靶点和研发新的治疗手段奠定基础。方法:运用cDNA微阵列、二维电泳和MALDI-TOF-MS技术,分析氯化锂-匹罗卡品(LiCl-PILO)致痫大鼠模型海马组织的基因表达谱和蛋白质表达谱,并对发现的差异表达基因和差异表达蛋白质进行分析和鉴定结果和。结论:发现LiCl-PILO致痫大鼠海马组织中192个基因差异表达,159条可在GenBank中登陆,其中表达上调的基因84条,表达下调的基因75条;筛选到78个差异表达蛋白质斑点,其中31个在癫痫组表达下调,47个在癫痫组表达上调。有5个蛋白质最终鉴定确认。本研究结果为运用蛋白质组学方法寻找癫痫治疗新靶点研究提供实验依据。 相似文献
992.
CD19 is required for normal antibody responses in mice. We have shown that CD19 enhances the activation of extracellular signal-regulated kinase (ERK) 2 by membrane (m) IgM but otherwise little is known of CD19 signaling in primary human cells. We now ask which pathways link CD19 with ERK2 in human tonsillar B cells. In analyses of signaling intermediates, the phosphatidylinositol 3-kinase (PI3K) inhibitor wortmannin partially suppressed the release of Ca2+ induced by coligation of CD19 and mIgM but the selective PKC inhibitor bisindolylmaleimide I (BIM-I) did not. The Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid, BIM-I and wortmannin each had only a small effect on ERK2 activation induced by surface IgM alone but blocked the enhancement of that activation by CD1 9/mIgM coligation. To analyze the mitogen-activated protein kinase (MAPK) cascade, we measured activation of Raf, MAPK- or ERK kinase (MEK) 1 and ERK2. CD19 consistently enhanced activation of ERK2 and MEK1. However, synergistic activation of Raf was variably observed. In subpopulation analyses, synergistic activation of Raf1 was consistently observed in the IgDlow but not in the IgDhigh cells. Thus, in normal human B cells, PI3K is upstream of the Ca2+ response while PI3K, Ca2+ release and protein kinase C are all required for ERK2 activation, and CD19 enhances the MAPK cascade at multiple levels, depending on the state of differentiation. 相似文献
993.
994.
X L Jiang D L Dillehay M P Everson A B Tilden E W Lamon 《International journal of immunopharmacology》1992,14(2):195-204
We evaluated the capacity of retinoids to potentiate proliferative responses of murine T-cells to recombinant human interleukin 2 (rIL-2). Concanavalin A (Con A) prestimulated spleen cells responded in a dose-dependent manner to added rIL-2. All-trans-retinoic acid (RA) at 10(-8) M potentiated the proliferative response by fivefold at saturating levels of IL-2. In similar experiments, two closely related retinamides, all-trans-(phenyl)retinamide (PR) and N-(4-hydroxyphenyl)retinamide (4-HPR), also potentiated murine splenocyte rIL-2 responses. Potentiation of IL-2-induced proliferation was dose-responsive to the concentration of added retinoid with peak potentiation occurring at 10(-10) - 10(-8) M in the presence of 10 U/ml rIL-2. Significant potentiation was observed at retinoid concentrations as low as 10(-14) M. Fluorescence flow cytometry of the responding cells revealed that among L3T4+, Lyt-2+ or total T-cells, at 72 h following Con A stimulation, essentially all of the cells expressed IL-2 receptors (IL-2R). This apparently represents near maximum IL-2R expression and treatment of the cells with retinoids did not increase IL-2R expression at that time point. The potentiation of IL-2 responses by retinoids was also observed with IL-2-dependent HT-2 cells, 98% of which were IL-2R positive. HT-2 proliferative responses to rIL-2 were potentiated as much as fourfold by 10(-10) M RA. HT-2 proliferative responses to rIL-2 were potentiated by all three retinoids dose dependently. Significant potentiation was observed with as little as 10(-14) M retinoid. Retinoids in the absence of IL-2 induced no proliferative responses. These data suggest that retinoids can augment the capacity of IL-2 to induce T-cell proliferation using Con A-activated murine splenic T-cell blasts and a long-term-cultured T-cell line. 相似文献
995.
38 000 MW antigen-specific major histocompatibility complex class I restricted interferon-gamma-secreting CD8+ T cells in healthy contacts of tuberculosis. 下载免费PDF全文
R J Wilkinson X Zhu K A Wilkinson A Lalvani J Ivanyi G Pasvol H M Vordermeier 《Immunology》1998,95(4):585-590
CD8+ T lymphocytes are required to protect mice against Mycobacterium tuberculosis, although in early infection the mechanism appears not to be via perforin or granzyme-mediated lysis of the infected target, and may be via interferon-gamma (IFN-gamma) production. We therefore investigated whether CD8+ T cells specific for the immunoprotective 38 000 MW antigen of M. tuberculosis could be detected in infected humans. Using a recombinant vaccinia virus expressing the 38 000 MW antigen of M. tuberculosis (rV38) and a control vaccinia virus (rVras) we demonstrated that both viruses stimulated IFN-gamma production from freshly isolated peripheral blood mononuclear cells (PBMC) in a 36-hr enzyme-linked immunospot assay. Cell depletion and antibody blockade established that the bulk of the 38 000 MW antigen-specific IFN-gamma response was mediated by CD8+, major histocompatibility complex class I-restricted T cells, whereas the anti-vaccinia virus response was predominantly mediated by CD4+ T cells. In further evaluations PBMC from all seven healthy tuberculosis-exposed contacts had a 38 000 MW antigen-specific IFN-gamma response, whereas seven patients with untreated sputum-positive pulmonary tuberculosis had very low levels of 38 000 antigen-specific IFN-gamma-producing cells. These preliminary observations demonstrate the utility of recombinant vaccinia viruses in restimulating freshly isolated CD4+ and CD8+ T cells. The bias towards a higher frequency of IFN-gamma-producing CD8+ T cells in contacts rather than patients may indicate a protective role for CD8+ cells in human tuberculosis. 相似文献
996.
The response of heat shock proteins 25 and 72 to ischaemia in different kidney zones 总被引:1,自引:0,他引:1
A. Schober E. Müller K. Thurau F. X. Beck 《Pflügers Archiv : European journal of physiology》1997,434(3):292-299
Induction of heat shock proteins (HSPs) following cell injury contributes to the protection of vital cell functions. It was,
therefore, of interest to study the effects of transient renal ischaemia on the abundance and distribution of two HSPs, HSP25
and HSP72, in renal tissue using Western-blot techniques. Analyses were performed on the supernatant (HSP25, HSP72) and pellet
(HSP25) of homogenates obtained from cortex (CX) and outer (OM) and inner (IM) medulla of the rat kidney immediately after
60 min of ischaemia followed by varying periods of reperfusion. Ischaemia of the left kidney caused HSP25 contents to decrease
in CX, OM and IM by 73, 89 and 54% respectively, compared with the corresponding zones of the contralateral control kidney.
This initial decrease in supernatant HSP25 was accompanied by an increased abundance of HSP25 in the pellet. Following reperfusion,
HSP25 contents in the supernatant gradually increased in CX and OM, reaching, after 24 h, values that were 5.4- and 2.5-fold
higher, respectively, than those in the control kidneys. After 7 or 14 days of reperfusion, HSP25 contents had not completely
normalised in CX, but had reached control levels in OM. In IM, the HSP25 content remained below control throughout the entire
reperfusion period. HSP72 (supernatant) was below the detection limit in the CX of the control kidney. Similar to the level
of HSP25, that of HSP72 was also markedly lower in OM and IM immediately after ischaemia. The intrarenal distribution of HSP72
and the sequence of zonal changes in HSP72 contents were similar to those observed for HSP25. These results are compatible
with the view that, during ischaemia and the initial reperfusion period, HSP25 migrates from the cytoplasmic compartment (supernatant)
into the nucleus and/or associates with cytoskeletal structures. The observation that both HSP25 and HSP72 are transiently
induced in CX and OM, but not in IM, may be explained by the fact that, while all kidney cells are exposed to ischaemic stress,
only inner medullary cells experience a major postischaemic attenuation of osmotic stress.
Received: 11 February 1997 / Received after revision and accepted: 26 March 1997 相似文献
997.
Primary gastrointestinal malignant lymphomas. A morphologic and immunohistochemical study 总被引:1,自引:0,他引:1
Thirty-nine primary gastric and 22 intestinal malignant lymphomas collected from 1969 to 1980 have been studied morphologically and immunohistochemically. Eighteen of the 61 gastrointestinal lymphomas were of low-grade malignancy (9 lymphoplasmacytoid/cytic, 3 centrocytic, 6 centroblastic/centrocytic) and 43 were of high-grade malignancy (14 centroblastic, 7 lymphoblastic, 22 immunoblastic malignant lymphomas) according to the Kiel classification. The peroxidase-antiperoxidase (PAP) method was used in 53 of the 61 cases. Twenty-seven of them revealed a monoclonal positivity for intracytoplasmic IgS: kappa light chains in 18 and lambda light chains in 7 cases. Two cases represented alpha chain disease, revealing only a heavy chain positivity. The most frequent staining pattern of the lymphoma cells was that of kappa/mu. Cells with a mixed centrocytic and plasma cell configuration (centrocytoid plasma cells) proved to be positive for intracytoplasmic IgS. Lymphoma cells of all tested cases proved to be negative for all histiocytic markers. Histologically and immunohistochemically, the Greek cases of primary gastrointestinal malignant lymphomas seem to resemble "western" type lymphomas. 相似文献
998.
Ten dibenzocyclooctadiene lignans were obtained from the ethereal soluble fraction of the dried roots and stems of KADSURA COCCINEA. Two of them were new compounds, named kadsutherin ( 8) and isokadsuranin ( 10). Their structures were elucidated on the basis of chemical and spectral analysis. 相似文献
999.
Fibrositis: symptom frequency and criteria for diagnosis. An evaluation of 291 rheumatic disease patients and 58 normal individuals 总被引:2,自引:0,他引:2
We administered a 17-item symptom questionnaire modified from Campbell to 155 patients with fibrositis diagnosed at 3 centers, each using different criteria sets. A high degree of agreement in symptom proportions was found among centers. "Fibrositic" symptoms were also common in 136 patients with a variety of rheumatic diseases but not in the 58 normal individuals studied. Symptoms distinguished fibrositis patients from normals easily, but had insufficient specificity to distinguish them from other rheumatic disease patients. The tender point count better separated fibrositic and nonfibrositic patients than historical criteria. No combination of questions and tender point count performed better than the tender point count alone. 相似文献
1000.
Series dead space (VdS) is assumed to be represented by that volume exhaled until alveolar gas is observed. Phase II of the single breath CO2-diagram contains the (flow, concentration and sequence weighted) distribution off all stationary interfaces (SI) expired before phase III. We describe a new method to estimate the mean value of VdS based on the differentiation of phase II. This approximation of VdS is called the Pre Interface Expirate (PIE) and is compared in this study with the integrative approach of Langley. Tidal volume (Vt) and PEEP were varied from 71 to 123% and from 0 to 6 cmH2O respectively.The estimation of VdS by differentiation of phase II (PIE) shows excellent reproducibility and depends only on phase II — not on phase III and IV as does VdS-Langley. PIE does not depend on Vt and PEEP per se but reflects the distension of convective airways due to elevated end-inspiratory airway pressure.Our results confirm the predictions of Paiva's model calculations in that the size of VdS is determined by the distension of airways rather than by the altered position of the SI. 相似文献