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91.
hTERT gene amplification and increased mRNA expression in central nervous system embryonal tumors
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Fan X Wang Y Kratz J Brat DJ Robitaille Y Moghrabi A Perlman EJ Dang CV Burger PC Eberhart CG 《The American journal of pathology》2003,162(6):1763-1769
High-level gains at 5p15, a chromosomal region including the human telomerase catalytic protein subunit (hTERT) gene, have been documented in several medulloblastomas. We therefore analyzed hTERT gene dosage in a group of medulloblastomas and other embryonal brain tumors using differential PCR. Amplification of the hTERT locus was detected in 15 of 36 (42%) tumors examined. To correlate gene amplification with message level, we used real-time quantitative PCR to measure hTERT mRNA in 50 embryonal brain tumors. hTERT mRNA was detected in all but one of these cases, and mRNA level correlated significantly with gene dosage (r = 0.82). Log-rank analysis of survival data revealed a trend toward poor clinical outcomes in patients with medulloblastomas containing high hTERT mRNA levels, but clinical follow-up was relatively short and the association was not statistically significant (P = 0.078). Comparative genomic hybridization was used to further analyze the tumor with the greatest hTERT gene dosage and mRNA level, a recurrent medulloepithelioma. hTERT was amplified in the recurrent tumor but not in the primary lesion, suggesting this locus can be involved in tumor progression. Our data indicate that hTERT gene amplification is relatively common in embryonal brain tumors, and that increased expression of hTERT mRNA may be associated with biologically aggressive tumor behavior. 相似文献
92.
Differential response to chemically altered polyethylene by activated mature human monocyte-derived macrophages 总被引:1,自引:0,他引:1
Macrophages and polyethylene (PE) particulate are currently recognized as being the two common denominators in the development of chronic inflammation, periprosthetic osteolysis, and subsequent implant failure. In this study, the effect of PE particulate surface chemistry on mature human monocyte-derived macrophage (MDM) function was investigated. Virgin high-density PE (HDPE: 4-10 microm) and HDPE oxidized by irradiation, thermal and chemical treatment were characterized by FT-IR and suspended in soluble type I collagen, which was subsequently solidified on glass coverslips. Human MDMs, derived from differentiating monocytes on polystyrene for 14 days, were trypsinized and cultured on collagen-particle substrata and collagen controls for 31 days. Analysis of conditioned media collected at 24h incubation showed a significantly higher level of IL-1beta secretion in virgin HDPE over oxidized HDPE or collagen controls, and a significant inhibition of IL-6 secretion in both virgin and oxidized samples. Esterase activity was increased in the medium at a significantly higher level in the virgin HDPE versus controls with the highest activity observed in oxidized HDPE at 31 days. These results illustrate the effect of PE particle surface chemistry (oxidation) on MDM cytokine secretion and esterase activity, and highlight the need to further investigate the potential of PE surface chemistry on modulating MDM function. 相似文献
93.
重组卡介苗及猪苓多糖对荷瘤小鼠巨噬细胞NO释放量的影响 总被引:4,自引:3,他引:4
目的 观察重组卡介苗(rBCG)和中药猪苓多糖(PPS),对荷瘤小鼠空巨噬细胞释放NO的影响。方法 将黑色素瘤细胞株B16接种于小鼠左大腿外侧皮下,建立荷瘤小鼠模型,分别用rBCG-IL-2,rBCG-IL-2 PPSPPS进行局部治疗。于给药后第1,2,3和5wk处死小鼠,用NO酶法测定小鼠腹腔巨噬细胞释放NO的水平,并观察不同实验组瘤体的变化。结果 rBCG-IL-2组小鼠腹腔巨噬细胞释放NO的水平最高。与对照组相比较,PPS组小鼠腹腔巨噬细胞释放NO的水平在第1wk与第2wk增高,第3wk起与对照组释放的NO水平没有差异。rBCG-IL-2组小鼠随给药时间的延长,皮下瘤体逐渐缩小。PPS组小鼠瘤体在给药后第1wk和第2wk生长缓慢,第3wk起瘤体生长速度明显增加。结论 rBCG-IL-2与PPS能提高小鼠腹腔巨噬细胞释放NO的水平,rBCG-IL-2能明显抑制肿瘤生长。 相似文献
94.
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96.
Jiang X Gao X Zheng H Yan M Liang W Shao Z Li W Zhang E Hu Y Hai R Yu D Kan B Xu J 《Clinical and diagnostic laboratory immunology》2004,11(6):1182-1184
Specific immunoglobulin G antibody for severe acute respiratory syndrome (SARS) coronavirus was detected in maternal blood, umbilical blood, and amniotic fluid from a pregnant SARS patient. Potential protection of fetus from infection was suggested. 相似文献
97.
Transfer of Tumor Necrosis Factor-α to Rat Lung Induces Severe Pulmonary Inflammation and Patchy Interstitial Fibrogenesis with Induction of Transforming Growth Factor-β1 and Myofibroblasts
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Patricia J. Sime Robert A. Marr David Gauldie Zhou Xing Bryan R. Hewlett Frank L. Graham Jack Gauldie 《The American journal of pathology》1998,153(3):825-832
Tumor necrosis factor-α is up-regulated in a variety of different human immune-inflammatory and fibrotic pulmonary pathologies. However, its precise role in these pathologies and, in particular, the mechanism(s) by which it may induce fibrogenesis are not yet elucidated. Using a replication-deficient adenovirus to transfer the cDNA of tumor necrosis factor-α to rat lung, we have been able to study the effect of transient but prolonged (7 to 10 days) overexpression of tumor necrosis factor-α in normal adult pulmonary tissue. We have demonstrated that local overexpression resulted in severe pulmonary inflammation with significant increases in neutrophils, macrophages, and lymphocytes and, to a lesser extent, eosinophils, with a peak at day 7. By day 14, the inflammatory cell accumulation had declined, and fibrogenesis became evident, with fibroblast accumulation and deposition of extracellular matrix proteins. Fibrotic changes were patchy but persisted to beyond day 64. To elucidate the mechanism underlying this fibrogenesis, we examined bronchoalveolar fluids for the presence of the fibrogenic cytokine transforming growth factor-β1 and tissues for induction of α-smooth muscle actin-rich myofibroblasts. Transforming growth factor-β1 was transiently elevated from day 7 (peak at day 14) immediately preceding the onset of fibrogenesis. Furthermore, there was a striking accumulation of myofibroblasts from day 7, with the most extensive and intense immunostaining at day 14, ie, coincident with the up-regulation of transforming growth factor-β1 and onset of fibrogenesis. Thus, we have provided a model of tumor necrosis factor-α-mediated pulmonary inflammation and fibrosis in normal adult lung, and we suggest that the fibrogenesis may be mediated by the secondary up-regulation of transforming growth factor-β1 and induction of pulmonary myofibroblasts. 相似文献
98.
目的:探讨高血压病患者血清可溶性E-选择素(sE-selectin)浓度与胰岛素抵抗、尿酸及血脂的关系。方法:测定186例高血压病患者(男75例,女111例)的空腹血清sE-selectin、血糖、胰岛素、尿酸、总胆固醇、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇的浓度,稳态模式评估法计算胰岛素抵抗指数(HOMA-IR)。分析血清sE-selectin浓度与其它各项参数的相关性。结果:以HOMA-IR50%位点,作为判断胰岛素抵抗的切割点,把高血压病患者分为胰岛素抵抗组(IR)与胰岛素敏感组(IS)。男性组血清sE-selectin浓度(50.1±17.8)μg/L显著高于女性组(40.6±16.6)μg/L;男性IR组(51.6±16.8)μg/L与IS组(48.5±18.8)μg/L无显著差异;女性IR组(45.1±18.0)μg/L显著高于IS组(36.0±13.7)μg/L。逐步回归分析显示,男性组HOMA-IR非血清sE-selectin浓度的独立预测因子,但女性组HOMA-IR是血清sE-selectin浓度的独立预测因子;尿酸和血脂均非血清sE-selectin浓度的独立预测因子。结论:女性原发性高血压患者血清sE-selectin浓度与胰岛素抵抗直接相关,男性则无直接相关;尿酸及血脂与血清sE-selectin浓度均无直接相关。 相似文献
99.
耳穴电参数时变关系实验表明,在测量起始t<2τ时,因瞬变作用,电位E(t)和压降U(t)为瞬态响应,响应函数呈指数关系,特征参数为弛豫时间τ,τ≈RC;t>2τ时,为时变间期。电路分析给出数学描述,并与耳穴和模拟实验结果较相符。提示,时变特征应以t>2τ后提取,静态电测量时,采样应避开瞬变期,可提高准确性。该工作对正确鉴别时变性和特征提取,全面认识耳穴电特性具有重要意义。 相似文献
100.