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991.
992.
Tumour-induced suppression of immune response and its correction 总被引:2,自引:0,他引:2
Banat GA Christ O Cochlovius B Pralle HB Zöller M 《Cancer immunology, immunotherapy : CII》2001,49(11):573-586
Immunosuppressive features of tumour cells are a major obstacle for immunotherapy of cancer. We recently noted that RENCA cells effectively interfere with the in vivo activation of RENCA-specific T cells. To unravel the underlying mechanism, we evaluated the influence of RENCA cells on a mixed-lymphocyte/ tumour reaction as well as an allogeneic mixed-lymphocyte reaction. We observed that RENCA cells were not directly immunosuppressive. Instead, they initiated deviation of an immune response in at least two independent directions: (i) expansion of a population of NK1.1+/CD3+ cells, which was accompanied by elimination of mainly CD4+ lymphocytes, and (ii) production of a leukocyte-derived inhibitory factor. Expression of the costimulatory molecule B7.1 by RENCA cells prevented induction of anergy, while expression of MHC class II molecules prevented expansion of NK1.1+ cells, which was accompanied by a significant decrease in cell death. Hence, an unimpaired response was observed only when RENCA cells expressed B7.1 plus MHC class II molecules. Thus, even if a tumour itself is not immunosuppressive, it can induce a strong deviation of the immune response. It is concluded that the first contact between elements of the immune system and the tumour cell can confer a severe bias on immunoregulatory circuits. 相似文献
993.
肾癌发病率约占全身恶性肿瘤的3%。肾癌组织学行为多变,预后有不确定性。外科手术可以治疗局限性肾癌,但有将近20%的局限性肾癌患者原发肿瘤切除后出现转移,而且肾癌对化疗及放疗均不敏感。基于此临床上开展了许多辅助试验的研究,并建立了许多模型来研究肾癌术后的预后,而模型的精准度一般都需要依据肾癌的生物标记物监测。有很多分子生物标记物已经证实和肾癌预后相关,如VHL、P53、Ki-67等,本文综述了肾癌预后的分子生物标记物的最新进展。 相似文献
994.
杜青山蔡伟董隽宋涛马鑫张旭 《现代生物医学进展》2012,12(13):2528-2530
目的:分析肾嗜酸细胞腺瘤的临床特征,指导并提升诊疗水平。方法:回顾性分析47例肾嗜酸细胞腺瘤的临床资料,包括临床特点、影像表现、病理特征、治疗方法及预后等方面。结果:47例患者中43例因查体偶然发现,仅4例表现为患侧腰痛症状。术前影像诊断中1例考虑嗜酸细胞腺瘤,1例考虑腺瘤,2例CT与MRI报告不一致(CT与MRI各有1例诊断良性,具体类型不确定),其余43例均诊断为肾细胞癌(1例囊性肾癌)。27例行肾癌根治性切除术,16例行肾部分切除术,4例行微波或射频消融术。所有患者术后病理均诊断为肾嗜酸细胞腺瘤,随访4~179月,均无转移或复发。结论:肾嗜酸细胞腺瘤作为一种与肾细胞癌难相鉴别的良性肿瘤,因缺乏特异性表现,极易误诊为肾细胞癌,因此对肾肿瘤患者应尽可能选择保肾治疗方案。 相似文献
995.
周森王辉陈志乐王小智王朝燕 《现代生物医学进展》2012,12(27):5309-5312
目的:探讨合并有急性肾损伤(AKI)的多器官功能障碍综合征(MODS)患者早期行高容量血液滤过(HVHF)治疗后对器官保护作用.方法:选择重症监护室于2008年6-2012年1月收治的MODS合并AKI并接受HVHF治疗的患者86例作为研究对象.根据RIFLE分级分为Risk组10例,Injury组17例,Failure组59例.记录患者HVHF治疗前后血肌酐(SCr)、氧合指数(PaO2/FiO2)、血管外肺水指数(EVLWI)、动脉血乳酸(Lac)、凝血酶原时间(PT)、天冬氨酸转氨酶(AST)、急性生理学与慢性健康状况评分系统Ⅱ (APACHE Ⅱ)评分以及28天存活率.结果:HVHF治疗后,Failure组SCr、EVLWI、Lac、PT、AST、APACHEⅡ评分均显著高于Risk组和Injury组,PaO2/FiO2显著低于Risk组和Injury组,差异有统计学意义(P<0.05).Risk组和Injury组在HVHF治疗后各指标差异均无统计学意义(P>0.05).Risk组28天存活率为60.0%,Injury组64.71%,Failure组存活率为66.10%,3组间差异均无统计学意义(P>0.05).结论:早期HVHF治疗对MODS合并AKI患者的器官具有保护作用,值得临床进一步研究. 相似文献
996.
997.
Patel VA Feng L Lee DJ Massenburg D Pattabiraman G Antoni A Schwartz JH Lieberthal W Rauch J Ucker DS Levine JS 《The Journal of biological chemistry》2012,287(17):13761-13777
Apoptosis allows for the removal of damaged, aged, and/or excess cells without harm to surrounding tissue. To accomplish this, cells undergoing apoptosis acquire new activities that enable them to modulate the fate and function of nearby cells. We have shown that receptor-mediated recognition of apoptotic versus necrotic target cells by viable kidney proximal tubular epithelial cells (PTEC) modulates the activity of several signaling pathways critically involved in regulation of proliferation and survival. Generally, apoptotic and necrotic targets have opposite effects with apoptotic targets inhibiting and necrotic targets stimulating the activity of these pathways. Here we explore the consequences of these signaling differences. We show that recognition of apoptotic targets induces a profound decrease in PTEC viability through increased responder cell death and decreased proliferation. In contrast, necrotic targets promote viability through decreased death and increased proliferation. Both target types mediate their effects through a network of Akt-dependent and -independent events. Apoptotic targets modulate Akt-dependent viability in part through a reduction in cellular β-catenin and decreased inactivation of Bad. In contrast, Akt-independent modulation of viability occurs through activation of caspase-8, suggesting that death receptor-dependent pathways are involved. Apoptotic targets also activate p38, which partially protects responders from target-induced death. The response of epithelial cells varies depending on their tissue origin. Some cell lines, like PTEC, demonstrate decreased viability, whereas others (e.g. breast-derived) show increased viability. By acting as sentinels of environmental change, apoptotic targets allow neighboring cells, especially non-migratory epithelial cells, to monitor and potentially adapt to local stresses. 相似文献
998.
999.
This study was designed to investigate the putative protective effect of β-casomorphin-7 on diabetic nephropathy in a rat model, and to explore the possible mechanism of this effect. SD rats were randomly divided into the following three groups: control group, diabetes group and β-casomorphin-7-treatment group. All rats were euthanized after 30 days with or without β-casomorphin-7 treatment. Biochemical parameters including blood glucose and renal function were quantified. The concentration of plasma TGF-β1 was measured by ELISA. Histopathological changes to the kidney were studied by Masson and Sirius red staining. Expressions of α-smooth muscle actin (α-SMA), E-cadherin, vimentin, cytokeratin19 and TGF-β1 mRNA in rat renal cortices were analyzed by real-time PCR. Changes in α-SMA and E-cadherin protein expression in rat renal cortices were quantified by Western blot. β-Casomorphin-7 treatment of diabetic rats reduced urinary glucose, urinary protein, serum creatinine, blood urinary nitrogen, plasma TGF-β1 and the ratio of kidney: body weight. Masson and Sirius red staining showed that β-casomorphin-7 treatment attenuated renal interstitial fibrosis in diabetic rats. Compared to the control rats, diabetic rats had elevated expressions of α-SMA, vimentin and TGF-β1 mRNA and α -SMA protein and decreased expression of E-cadherin and cytokeratin19 mRNA, and E-cadherin protein. β-Casomorphin-7 treatment of diabetic rats partially normalized these changes. Our results suggest that administration of β-casomorphin-7 attenuates renal interstitial fibrosis caused by diabetes. This protective effect may be associated, in part, with down regulation of epithelial-mesenchymal transition of renal tubular epithelial cells. 相似文献
1000.