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41.
目的探讨环氧化物酶-2(cyclooxygenase type 2,COX-2)及Ⅰ型前列腺素合成酶(membrane associated prostaglandin E-1,mPGES-1)在人颈动脉粥样硬化斑块中的表达变化及作用机制。方法收集24例人颈动脉粥样硬化斑块标本和10例肠系膜动脉标本做对照组,应用免疫组织化学及逆转录PCR方法测定COX-2及mPGES-1mRNA表达水平,Western印记方法检测COX-2及mPGES-1的蛋白表达水平。比较不同程度动脉粥样硬化组织间COX-2、mPGES-1 mRNA表达水平及蛋白表达水平。结果颈动脉粥样硬化斑块组的免疫组织化学染色检测COX-2和mPGES-1呈阳性表达,斑块组COX-2 mRNA和mPGES-1 mRNA表达与对照组相比上调,差异有统计学意义(P<0.05);COX-2及mPGES-1 mRNA上调水平相关(P<0.05);颈动脉粥样硬化斑块的COX-2蛋白表达上调水平与对照组相比差异有统计学意义(P<0.05);颈动脉粥样硬化斑块COX-2、mPGES-1 mRNA及蛋白表达水平与病理损害程度有关,差异有统计学意义(P<0.05)。结论COX-2及mPGES-1基因表达水平上调可能是进展性动脉粥样硬化损害的关键因素。 相似文献
42.
Inflammatory pseudotumor of lymph node and spleen: An entity biologically distinct from inflammatory myofibroblastic tumor 总被引:6,自引:0,他引:6
Jeffery L. Kutok MD PhD Geraldine S. Pinkus MD David M. Dorfman MD PhD Christopher D. M. Fletcher MD FRCPath 《Human pathology》2001,32(12):1382-1387
Inflammatory pseudotumors (IPTs) of the lymph node and spleen are an uncommon, benign cause of lymphadenopathy and/or splenomegaly that often bear striking clinicopathologic similarities to the inflammatory myofibroblastic tumors (IMTs) found in soft tissues. These tumors have classically been grouped together under the umbrella category of "inflammatory pseudotumor." Recent evidence shows that IMTs are in fact neoplastic processes that often harbor balanced chromosomal translocations involving the ALK kinase gene. These translocations result in expression of ALK kinase in IMTs as assessed by immunohistochemical studies. However, the relationship between IMT and IPT of the lymph node and spleen is uncertain. To determine if ALK tyrosine kinase expression is also present in IPT, 13 cases of IPT (9 involving lymph nodes, 4 splenic lesions) were examined for the presence of ALK tyrosine kinase by immunohistochemical staining on paraffin-embedded tissue. In addition, in situ hybridization studies for Epstein-Barr virus--encoded RNAs (EBER) and immunoperoxidase studies for human herpesvirus-8 (HHV8)--specific proteins were performed. All cases had clinical, morphologic, and immunophenotypic findings typical of IPT and had varying proportions of fibroblastic and inflammatory components. Age ranged from 11 to 75 (median, 40) years; 8 subjects were male, and 5 were female. None of the cases (0 of 13) had positive staining for ALK kinase or HHV8, and in 1 a lymph node (1 of 13) was focally positive for EBV (EBER) by in situ hybridization. The absence of ALK kinase as detected by immunohistochemical studies in IPT of the lymph node and spleen suggests that this entity is biologically distinct from the histologically similar IMT. 相似文献
43.
Xavier Sastre‐Garau Jrme Couturier Josette Derr Alain Aurias Jerzy Klijanienko Ral Lagac 《The Journal of pathology》2002,196(1):97-102
Inflammatory myofibroblastic tumours (IMTs) were initially considered to be benign reactive processes, but cases with an unfavourable outcome have been reported. Moreover, clonal genetic alterations have recently been published in some cases, suggesting that IMT may represent a malignant neoplastic entity. This paper reports a case of IMT that developed in the mammary gland, an unusual site. The histological picture was characterized by a proliferation of spindle cells with little cellular atypia and rare mitoses, associated with a polymorphous inflammatory infiltrate. Their immunophenotype, characterized by the expression of vimentin, smooth muscle actin, and cytokeratins, corresponded to that of myofibroblasts. Cytogenetic analysis revealed the clonal nature of the lesion. The modal karyotype was 48, X, ins(2;X)(q34;p21.2p22.2), +7, del(9)(p23), +19. Including the present observation, a 9p deletion has now been found in three cases of IMT. These observations show that IMT may be a clonal neoplasm, even in sites different from deep soft tissues. 相似文献
44.
HLA antigens, psoriasis and acute anterior uveitis in Bechterew's syndrome (ankylosing spondylitis) 总被引:1,自引:0,他引:1
One hundred and twenty-two consecutively hospitalized patients with ankylosing spondylitis (AS) were reexamined. Ninety-two per cent were HLA B27 positive. Of the HLA B27 negative patients, 60% were found to have psoriasis, as opposed to 11 % of the HLA B27 positive patients. Acute anterior uveitis (AAU) was found only in HLA B27 positive patients, and more frequently in males than in females. The genetic and clinical heterogeneity of AS, together with the overlapping clinical criteria for AS and psoriatic spondylitis, may make the term "Bechterew's syndrome" preferable. Based on these findings and previous reports, we conclude that (i) AAU is a manifestation of Bechterew's syndrome in HLA B27 positive patients, (ii) HLA B27 negative patients without any obvious accompanying manifestations may suffer from psoriatic spondylitis, and (iii) genetic predisposition to psoriasis in persons who are HLA B13, B17 and B37 negative, may interact with the genetic predisposition to Bechterew's syndrome in HLA B27 positive persons and produce Bechterew's syndrome with psoriasis or psoriasis-like skin eruptions. 相似文献
45.
46.
47.
Increased lymphocyte trafficking to colonic microvessels is dependent on MAdCAM-1 and C-C chemokine mLARC/CCL20 in DSS-induced mice colitis 总被引:5,自引:0,他引:5
Teramoto K Miura S Tsuzuki Y Hokari R Watanabe C Inamura T Ogawa T Hosoe N Nagata H Ishii H Hibi T 《Clinical and experimental immunology》2005,139(3):421-428
Although enhanced lymphocyte trafficking is associated with colitis formation, little information about its regulation is available. The aim of this study was to examine how the murine liver and activation-regulated chemokine (mLARC/CCL20) contributes to lymphocyte recruitment in concert with vascular adhesion molecules in murine chronic experimental colitis. T and B lymphocytes isolated from the spleen were fluorescence-labelled and administered to recipient mice. Lymphocyte adhesion to microvessels of the colonic mucosa and submucosa was observed with an intravital microscope. To induce colitis, the mice received two cycles of treatment with 2% dextran sodium sulphate (DSS). In some of the experiments antibodies against the adhesion molecules or anti-mLARC/CCL20 were administered, or CC chemokine receptor 6 (CCR6) of the lymphocytes was desensitized with excess amounts of mLARC/CCL20. Significant increases in T and B cell adhesion to the microvessels of the DSS-treated mucosa and submucosa were observed. In chronic colitis, the accumulation of lymphocytes was significantly inhibited by anti-mucosal addressin cell adhesion molecule (MAdCAM)-1 mAb, but not by anti-vascular cell adhesion molecule-1. In DSS-treated colonic tissue, the expression of mLARC/CCL20 was significantly increased, the blocking of mLARC/CCL20 by monoclonal antibody or the desensitization of CCR6 with mLARC/CCL20 significantly attenuated the DSS-induced T and B cell accumulation. However, the combination of blocking CCR6 with MAdCAM-1 did not further inhibit these accumulations. These results suggest that in chronic DSS-induced colitis, both MAdCAM-1 and mLARC/CCL20 may play important roles in T and B lymphocyte adhesion in the inflamed colon under flow conditions. 相似文献
48.
Chen Y Zhang J Moore SA Ballas ZK Portanova JP Krieg AM Berg DJ 《International immunology》2001,13(8):1013-1020
Unmethylated CpG motifs found in bacterial DNA are potent activators of the innate and acquired immune systems, and rapidly induce the production of proinflammatory cytokines. We hypothesized that CpG DNA may also elicit the production of prostaglandins (PG), which are central lipid mediators of the immune and inflammatory response. To test our hypothesis, we stimulated murine spleen cells and RAW 264.7 murine macrophage cells with CpG DNA and assessed the effects on the PG synthesis pathway. Compared to control, DNA-containing CpG motifs induced >5-fold increase in PGE (2) production and rapidly up-regulated cyclooxygenase-2 (COX-2) at both the mRNA and protein level. CpG DNA was an extremely strong inducer of COX-2 as concentrations as low as 3 ng/ml induced COX-2 protein expression. The CpG DNA-induced PGE (2) down-regulated the immune response elicited by CpG. Blockade of PGE (2) production with selective COX-2 inhibitors or neutralizing anti-PGE (2) antibody markedly enhanced IFN-gamma secretion in vitro from CpG DNA-stimulated spleen cells. Moreover, selective COX-2 inhibition increased CpG DNA-induced IFN-gamma secretion in vivo. Inhibition of COX-2 also increased CpG DNA-induced lytic activity of NK cells. Taken together, these data indicate that DNA containing CpG motifs is a potent inducer of COX-2 and PGE (2) production. CpG-induced PG may subsequently down-regulate the immune and inflammatory responses elicited by the CpG DNA. 相似文献
49.
多器官功能障碍综合征小鼠脾脏树突状细胞与炎症因子变化的关系 总被引:1,自引:0,他引:1
目的探讨多器官功能障碍综合征(MODS)病程中脾脏树突状细胞(DC)变化对炎症因子的影响与作用。方法采用腹腔注射酵母多糖的方法复制小鼠MODS模型,分为正常对照组和MODS组。采用流式细胞技术检测脾脏DC免疫表型,运用免疫组化技术检测脾脏中促炎因子IL-1β与抗炎因子IL-10的表达,计量观察DC与炎症因子在病程中的变化并做相关分析。结果伤后6h组,脾脏中CD11c^+/MHC-Ⅱ’DC数目与IL-18’细胞数目均明显增多,至24h组达峰值。自48h组,CD11c^+/MHC-Ⅱ’DC与IL-1β’细胞含量开始下降,在6天组和10~12天组降至正常组或低于正常组含量;而同时CD11c^+/MHC-Ⅱ^-DC和IL-10阳性细胞含量则相对增多,至10~12天组阳性细胞含量显著升高达到峰值。结论DC的活性在MODS病程早期与IL-1β表达呈正相关性,在病程晚期与IL-10表达呈负相关,提示脾脏DC活性变化与促炎因子和抗炎因子均有密切的相关性。 相似文献
50.