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71.
CD44 is a family of cell adhesion molecules involved in a variety of cellular functions. The present study analysed the expression of two CD44 isoforms in serous effusions of patients diagnosed with ovarian carcinoma and corresponding primary and metastatic lesions. Fifty-eight effusions, 23 primary ovarian tumours, and 44 metastatic lesions were studied for protein expression of CD44s and v3-10 using immunohistochemistry. Results were correlated with clinical parameters. CD44v3-10 was seen in carcinoma cells in the majority of cases at all sites. Malignant effusions showed an up-regulation of CD44s compared to both primary tumours and metastatic solid lesions. Mesothelial cells frequently expressed CD44s, but were rarely immunoreactive for v3-10. CD44s immunoreactivity in cancer cells in effusions was significantly more often observed in patients with FIGO stage 3 than in stage 4 patients (P = 0.045). Staining results did not correlate with age, effusion site, metastatic site, tumour grade or residual tumour mass after initial surgery. Likewise, comparison of overall and disease-free survival with expression of the CD44 isoforms studied did not reveal any statistically significant associations. The up-regulation in CD44 levels in effusions, primarily in stage 3 disease, suggests that adhesion of ovarian carcinoma cells to mesothelium may be regulated at the level of CD44s expression, and provides further evidence of phenotypic alteration in the transition from primary tumour cell clones to effusions. The similar expression profile of CD44 in carcinoma cells in peritoneal and pleural effusions supports our previous observations and the hypothesis that carcinoma cells in peritoneal effusions are truly metastatic. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
72.
Human keratinocytes (HK) generate nitric oxide (NO) and proinflammatory mediators following activation with either IgE/anti-IgE immune complexes or a combination of lipopolysaccharide (LPS) and interferon-γ (IFN-γ). Recently, interleukin-10 (IL-10) has been shown to down-regulate various inflammatory responses and to be secreted by lymphocytes and dendritic cells during skin inflammatory reactions. We show here that IL-10 down-regulates the production of tumor necrosis factor (TNF)-α and IL-6 by activated HK. Also, induction of inducible nitric oxide synthase (iNOS) expression in HK by IgE/anti-IgE or LPS/IFN-γ is significantly reduced by the addition of IL-10. This effect is dose dependent and correlates with reduction of iNOS mRNA production and enzyme level. Therefore, IL-10 down-regulates NO-mediated HK inflammatory responses and may thus participate in the regulation of the skin immune network.  相似文献   
73.
74.
eIF3S10在肺癌组织中的表达及与化疗反应的关系   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:研究eIF3S10在肺癌中的表达及其与化疗反应的关系,探讨其在肺癌预后中的作用。方法:收集在湖南省肿瘤医院治疗的31例支气管纤维镜检肺癌组织和20例肺良性病变组织及10例肺癌边缘正常组织的石蜡组织切片。采用免疫组织化学技术检测eIF3S10蛋白在肺癌组织、肺良性病变组织和正常肺组织中的表达,并分析eIF3S10表达水平与患者化疗敏感性的关系。结果:肺正常组织和肺良性病变组织中eIF3S10阳性率分别为30%和15%,而肺癌组织中eIF3S10的阳性率达61%。eIF3S10表达水平与化疗敏感性存在一定相关性。结论:肺癌组织中有eIF3S10过表达,而肿瘤组织eIF3S10表达过高可能提示患者对化疗反应敏感。  相似文献   
75.
Immunological abnormalities present in HIV-1-infected individuals often reflect an imbalance of cytokine production. The HIV-1 gp120 has the ability to induce a number of cytokines, and to enhance immunoglobulin release by normal peripheral blood mononuclear cells (PBMC) in vitro, in the absence of IL-2 production and of lymphoproliferation. This study provides evidence that gp120 is a potent IL-10 inducer in normal PBMC cultures. The pattern of other cytokines induced by gp120 includes interferon-alpha (IFN-alpha) and IFN-gamma, tumour necrosis factor-alpha (TNF-alpha), IL-6, IL-1 alpha and -beta, and not IL-2 and IL-4. These findings further define the pattern of cytokine release induced by gp120 on human resting PBMC. Furthermore, the present findings roughly parallel those observed both in the sera of patients and in the mononuclear cells from HIV+ individuals early after infection, suggesting that gp120 could be a good candidate as one of the agents responsible for cytokine dysregulation observed in HIV-1-infected individuals.  相似文献   
76.
Summary Coenzyme Q10 (CoQ10) is indispensable in mitochondrial bioenergetics and for human life to exist. 88/115 patients completed a trial of therapy with CoQ10 for cardiomyopathy. Patients were selected on the basis of clinical criteria,X-rays, electrocardiograms, echocardiography, and coronary angiography. Responses were monitored by ejection fractions, cardiac output, and improvements in functional classifications (NYHA). Of the 88 patients 75%–85% showed statistically significant increases in two monitored cardiac parameters. Patients with the lowest ejection fractions (approx. 10%–30%) showed the highest increases (115%–210%) and those with higher ejection fractions (50%–80%) showed increases of approx. 10%–25% on therapy. By functional classification, 17/21 in class IV, 52/62 in class III, and 4/5 in class II improved to lower classes. Clinical responses appeared over variable times, and are presumably based on mechanisms of DNA-RNA-protein synthesis of apoenzymes which restore levels of CoQ10 enzymes in a deficiency state. 10/21 (48%) of patients in class IV, 26/62 (42%) in class III, and 2/5 (40%) in class II had exceptionally low control blood levels of CoQ10. Clinical responses on therapy with CoQ10 appear maximal with blood levels of approx. 2.5 µg CoQ10/ml and higher during therapy.Abbreviations CHF Congestive heart failure - CO Cardiac output - CoQ10 Coenzyme Q10 - EF Ejection fraction - IC Impedance cardiography - NYHA New York Heart Association - STI Systolic time interval  相似文献   
77.
The presence of histidine-rich protein (HRP) related genes and gene products in Plasmodium falciparum was demonstrated using a synthetic pentahistidine-encoding oligonucleotide and a cloned HRP cDNA probe prepared from the avian parasite P. lophurae. In Northern blotting experiments, two knobby clones of P. falciparum were found to contain a 3500 nucleotide RNA species that hybridized with the oligonucleotide and HRP cDNA probes. As this component had the expected size for an mRNA encoding an 80-90 kDa protein and was absent from two knobless clones of P. falciparum, we concluded that it represented a 'knob protein' mRNA. Using the restriction enzyme EcoRI, three identical cross-hydribizing HRP gene fragments were found in the DNA of both knobby and knobless clones of P. falciparum. These fragments differed in size from those present in P. lophurae. These results suggest that the absence of knob protein mRNA in knobless clones is not due to loss of the corresponding gene(s).  相似文献   
78.
Dendritic cells (DC) are crucial gatekeepers in regulating immunity. Whereas mature immunostimulatory myeloid DC (DC(ims)) potently promote immune responses, IL-10-induced myeloid DC (DC-IL-10) counteract T cell activation. To elucidate the molecular repertoire by which DC-IL-10 secure reduced T cell activation, comparative gene expression profiling was done using Affymetrix U133A microarrays. Among the genes overexpressed in DC-IL-10, eight immunoreceptor tyrosine-based inhibitory motif (ITIM)-containing inhibitory molecules (ILT2, ILT3, ILT4, ILT5, DCIR, PILRA, FcgammaRIIB, SLAM) were found. Phenotypic analysis of DC-IL-10 defined an ILT(high) DC subset further characterized by expression of CD14, TLR2, DC-SIGN, and CD123 and the lack of lymphocyte, monocyte/macrophage, and plasmacytoid DC markers such as CD3, CD8, and CD68. A unique feature of the ILT(high) DC subset was expression of the novel DC marker BDCA3, which was not detected on monocytes, immature DC, DC(ims), or ILT(low) DC-IL-10. While the allogeneic T cell proliferation induced by the entire DC-IL-10 population was approximately 30% of that stimulated by DC(ims), allogeneic MLR responses driven by the ILT(high) DC subset were reduced to 8% of the allostimulatory capacity of DC(ims), although secretion of the inhibitory cytokine IL-10 and other Th1/Th2-associated cytokines was similar in these cells.  相似文献   
79.
目的:确定SLE模型小鼠IL-10RA基因变异及其与SLE表现型是否存在关联。方法:用微卫星遗传标记及数量性状位点(QTL)分析方法确定SLE模型小鼠B/W F1的SLE易感基因精确染色体定位并选取候选易感基因,对候选易感基因进行测序分析,选取有基因序列异常的候选易感基因进行PCR-SSCP分析,确定候选易感基因碱基序列变异位点与抗染色质抗体、抗DNA抗体,抗组蛋白抗体及蛋白尿等SLE表现型的相关关系。结果:QTL分析结果表明B/W F1×NZB小鼠抗染色质抗体易感基因与NZW型IL-10RA基因紧密连锁;测序分析发现IL-10RA基因编码区有18处碱基变异,其中7处碱基变异将导致编码氨基酸的变异;抗染色质抗体、抗DNA抗体,抗组蛋白抗体及蛋白尿等SLE表现型与NZW型IL-10RA基因密切相关。另一种SLE模型小鼠MRL的IL-10RA基因存在相同变异。结论:NZW小鼠IL-10RA基因编码区碱基序列存在变异,B/W F1×NZB小鼠SLE表现型与NZW小鼠第9染色体IL-10RA编码区碱基变异相关,提示IL-10RA可能是SLE模型小鼠的一个SLE易感基因。  相似文献   
80.
IL-4 and IL-10 modulate autoimmune haemolytic anaemia in NZB mice   总被引:2,自引:0,他引:2  
New Zealand Black (NZB) mice spontaneously develop autoimmune haemolytic anaemia (AIHA). Here the effect of injecting NZB mice with plasmids encoding IL-4 (pIL-4) or IL-10 (pIL-10) on NZB disease was tested. Both constructs delayed the development of anaemia as judged by increased haematocrit values as compared with controls, but neither altered the IgG1 to IgG2 red blood cell (RBC) bound autoantibody levels. The increased haematocrit value was associated temporally with increased RBC bound IgG in NZB mice treated with pIL-10, but not pIL-4. By contrast, up-regulation of splenic macrophage FcgammaRIIb2 mRNA was associated temporally with increased haematocrit values in NZB mice given pIL-4. However, no such increase occurred in NZB mice that inhaled a peptide containing a dominant T-cell epitope, although this treatment is known to bias the autoimmune response towards Th2 and to reduce the severity of anaemia. It is considered that IL-4 treatment, in part, ameliorates NZB anaemia by increasing the expression of the inhibitory FcgammaRIIb2 and thereby reducing the capacity of splenic macrophages to phagocytose autoantibody coated RBC, but that this mechanism does not explain the beneficial effects of the inhaled peptide.  相似文献   
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