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81.
Tumor cells have the ability to exploit stromal cells to facilitate metastasis. By using malignant melanoma as a model, we show that the stroma adjacent to metastatic lesions is enriched in the known metastasis-promoting protein S100A4. S100A4 stimulates cancer cells to secrete paracrine factors, such as inflammatory cytokines IL8, CCL2 and SAA, which activate stromal cells (endothelial cells and monocytes) so that they acquire tumor-supportive properties. Our data establishes S100A4 as an inducer of a cytokine network enabling tumor cells to engage angiogenic and inflammatory stromal cells, which might contribute to pro-metastatic activity of S100A4.  相似文献   
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Bovine nodular thelitis is a granulomatous dermatitis associated with infection with acid-fast bacteria. To identify the mycobacterium responsible for this infection, we conducted phylogenetic investigations based on partial sequencing of 6 genes. These bacteria were identified as an undescribed Mycobacterium species that was phylogenetically related to M. leprae and M. lepromatosis.  相似文献   
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Objectives: Conjugated linoleic acid (CLA) isomers have been shown to possess anti-inflammatory activity in the central nervous system. In this study, we aimed to evaluate whether modulation of the fatty acid profile by the CLA isomers c9,t11 or t10,c12CLA was associated with changes in the expression of pro-inflammatory molecules in human astrocytes.

Methods: Cultured astrocytes were treated for 6 days with 100?µM fatty acids (c9,t11CLA or t10,c12CLA or oleic acid). Following the treatment, the fatty acid profile of the cell and pro-inflammatory molecule expression were assessed.

Results: Only the t10,c12CLA isomer induced a significant decrease in arachidonic acid and increased the ratio of docosahexaenoic acid/eicosapentaenoic acid, which constitutes indirect evidence of peroxisome proliferator-activated receptor alpha activation. Inhibition of tumour necrosis factor-α, interleukin-1β, and RANTES expression was observed in astrocytes treated with c9,t11CLA and t10,c12CLA.

Discussion: Current data demonstrate that CLA isomers, particularly t10,c12, may affect neuroinflammation by reducing the pro-inflammatory molecules in cultured astrocytes, suggesting a potential nutritional role of CLA isomers in modulating the astrocyte inflammatory response.  相似文献   

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The aims of the study were to investigate healthy subjects’ performance on a clinical test of high-level language (HLL) and how it is related to demographic characteristics and verbal working memory (VWM). One hundred healthy subjects (20–79 years old) were assessed with the Swedish BeSS test (Laakso, Brunnegård, Hartelius, & Ahlsén, 2000) and two digit span tasks. Relationships between the demographic variables, VWM and BeSS were investigated both with bivariate correlations and multiple regression analysis. The results present the norms for BeSS. The correlations and multiple regression analysis show that demographic variables had limited influence on test performance. Measures of VWM were moderately related to total BeSS score and weakly to moderately correlated with five of the seven subtests. To conclude, education has an influence on the test as a whole but measures of VWM stood out as the most robust predictor of HLL.  相似文献   
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目的:研究WWOX基因对人急性淋巴细胞性白血病细胞CCRF-CEM细胞凋亡及细胞周期的影响及分子机制。方法:体外培养CCRF-CRM细胞系,将WWOX基因转染入CCRF-CEM细胞,建立高表达WWOX的CCRF-CEM细胞,流式细胞仪法测定CCRF-CEM细胞的细胞周期和凋亡,Western blot法测定WWOX基因、细胞周期和凋亡相关因子的蛋白表达,qRT-PCR法测定caspase-3的mRNA表达。结果:与对照组和空白质粒组相比,转染入WWOX的CCRF-CEM细胞的WWOX蛋白表达显著增加,G0/G1期的细胞比例显著增加,凋亡细胞比例显著增加;CCRF-CEM细胞中cyclin D1、cyclin E、CDK2的蛋白表达显著降低而Wnt-5α和JNK的蛋白表达显著增加,caspase-3的mRNA表达促进CCRF-CEM细胞的凋亡。结论:WWOX基因在急性淋巴细胞性白血病CCRF-CEM细胞中发挥抑癌基因作用,可以有效促进细胞凋亡并抑制细胞周期进程。  相似文献   
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