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71.

Background

Programmed death ligand-1 (PD-L1) is a potential predictive biomarker for immunotherapy in several malignancies. However, the expression level and clinical significance of PD-L1 in von Hippel–Lindau (VHL)-associated hereditary clear-cell renal cell carcinoma (ccRCC) remain unclear.

Patients and Methods

Surgical specimens were recruited from 129 patients with sporadic ccRCC and 26 patients with VHL-associated hereditary ccRCC. The PD-L1 expression level was assessed using immunohistochemistry. Correlations between PD-L1 expression and clinicopathological features were analyzed.

Results

In sporadic ccRCC, the positive expression rate of PD-L1 was 47.3% (61/129). Positive PD-L1 expression was correlated with advanced tumor T stage (P = .011), higher Fuhrman nuclear grade (P = .022), poor disease-free survival (P = .037), and sex (P = .025). In the VHL-associated hereditary ccRCC, positive PD-L1 expression rate was 34.6% (9/26), lower than that in sporadic ccRCC. Positive PD-L1 was correlated with higher Fuhrman nuclear grade (P = .008), but not with sex, age, tumor stage, or the onset age of VHL-associated tumors.

Conclusion

Positive PD-L1 expression was correlated with the aggressive clinicopathological features in sporadic and VHL-associated hereditary ccRCC. Whether PD-L1 expression level in ccRCC is related to the effectiveness of programmed death-1/PD-L1 checkpoint inhibitor immunotherapy needs to be further investigated.  相似文献   
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目的探讨高血压合并脑卒中患者的血浆同型半胱氨酸(Hcy)水平与其他危险因素对于脑卒中复发的影响。 方法分析徐州市中心医院心内科和徐州医科大学附属医院神经外科自2012年5月至2013年12月收治的1623例高血压脑卒中患者的基线资料,中位随访4.9年,根据随访事件中是否发生脑卒中分为复发组(312例)与未复发组(1311例)。Kaplan-Meier生存分析比较不同危险因素脑卒中复发率的差异,单因素与多因素Cox回归模型分析影响脑卒中复发的独立危险因素,以及危险因素之间的交互作用。 结果复发组年龄、空腹血糖、Lg Hcy的水平,以及糖尿病、房颤的患病率均高于未复发组(P<0.05)。Kaplan-Meier生存分析显示,糖尿病、房颤、年龄≥60岁、空腹血糖≥7.0 mmol/L、Hcy≥15 μmol/L的脑卒中复发率明显升高(Log-rank检验,P<0.05)。多因素Cox回归模型分析显示,高龄、Lg Hcy水平升高,以及房颤、糖尿病是脑卒中复发的独立危险因素。Lg Hcy分别与糖尿病、空腹血糖、年龄存在交互作用。 结论血浆Hcy水平升高既是高血压合并脑卒中患者卒中复发的独立危险因素,又通过与糖尿病、高龄、空腹血糖水平升高的交互作用显著增加脑卒中复发风险。  相似文献   
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病理学是一门理论与形态相结合的学科,实验课教学知识点多,难以理解。本教研室在实验课中将案例教学(case-based learning,CBL)与标本教学相结合,从案例的选择、案例的准备、案例教学的实施方法及注意事项等方面对病理学实验教学进行探讨;通过60名学生的实验课成绩、理论课成绩对比分析发现,案例教学的引入能有效提高学生对病理学学习的积极性,扩展了学生的知识面,增强了学生自学能力、团队协作能力、语言表达能力,巩固了学生对理论知识的掌握,提高了学习成绩,更好地提升了教学质量。  相似文献   
78.
BACKGROUNDCholangiocarcinoma is a disease with a high mortality rate. Our previous study revealed that cholelithiasis patients who undergo endoscopic sphincterotomy (ES)/endoscopic papillary balloon dilatation are at a higher risk for subsequent cholangiocarcinoma than cholelithiasis patients who undergo cholecystectomy.AIMTo clarify the relationship between recurrent biliary events and subsequent cholangiocarcinoma risk in choledocholithiasis patients.METHODSFrom one million random cases in the Taiwan National Health Insurance Research Database 2004–2011, we selected symptomatic choledocholithiasis patients older than 18 years who were admitted from January 2005 to December 2009 (study group). Cases for a control group were defined as individuals who had never been diagnosed with cholelithiasis, matched by sex and age in a 1:3 ratio. The study group was further divided into ES/endoscopic papillary balloon dilatation, both ES/endoscopic papillary balloon dilatation and cholecystectomy, and no intervention groups.RESULTSWe included 2096 choledocholithiasis patients without previous intervention or cholangiocarcinoma. A total of 12 (2.35%), 11 (0.74%), and 1 (1.00%) subsequent cholangiocarcinoma cases were diagnosed among 511 ES/endoscopic papillary balloon dilatation patients, 1485 patients with no intervention, and 100 ES/endoscopic papillary balloon dilatation and cholecystectomy patients, respectively. The incidence rates of recurrent biliary event were 527.79/1000 person-years and 286.69/1000 person-years in the subsequent cholangiocarcinoma and no cholangiocarcinoma group, showing a high correlation between subsequent cholangiocarcinoma risk and recurrent biliary events.CONCLUSIONCholedocholithiasis patients who undergo further cholecystectomy after ES/endoscopic papillary balloon dilatation have decreased subsequent cholangiocarcinoma risk due to reduced recurrent biliary events.  相似文献   
79.
目的:研究斑蝥提取物(cantharis extract,CTE)体外诱导人胆管癌QBC939细胞凋亡作用及其对细胞周期分布的影响。方法:体外培养人胆管细胞癌QBC939细胞,CTE作用于QBC939细胞48小时,利用CCK-8法检测QBC939细胞增殖率并计算半数抑制浓度(IC50);光学显微镜下观察细胞形态的改变;AnnexinⅤ/PI双染法检测细胞凋亡情况;用PI染色检测对QBC939细胞周期分布的影响;Western blot法检测细胞凋亡相关蛋白及细胞周期相关蛋白表达变化。结果:CTE显著抑制QBC939细胞增殖,呈浓度及时间依赖性,处理48小时的IC50为4.16μg/ml。经光学显微镜下观察可见随着药物浓度增加,细胞密度减少,游离变圆的细胞明显增多。AnnexinⅤ/PI双染流式凋亡检测示,随着药物浓度的增加,凋亡细胞数量逐渐增加,药物处理组(1.25μg/ml、2.5μg/ml、5.0μg/ml)的细胞凋亡率分别为(9.52±1.01)%、(15.62±1.88)%、(46.03±4.88)%,与对照组(4.59±0.43)%比较,差异有统计学意义(P<0.05)。PI检测细胞周期示,CTE能将QBC939细胞周期阻滞在G2/M期,随药物浓度增加而增加,G2/M期细胞比例逐渐增加,与对照组比较差异有统计学意义,而G1期细胞比例逐渐减少。Western blot检测示,CTE处理组细胞增殖相关蛋白增殖细胞核抗原(PCNA)表达降低,相对蛋白表达量与对照组比较,差异有统计学意义(P<0.05);Bcl-2家族蛋白Bax和Bid表达增加,而Bcl-2、Mcl-1表达降低,抑制凋亡蛋白家族蛋白Survivin表达显著下降,凋亡相关蛋白半胱氨酸蛋白水解酶3(Caspase-3)表达下降,与对照组比较CTE处理组上述相对蛋白表达量差异有统计学意义(P<0.05);CTE处理组细胞周期相关蛋白Chk1表达无显著改变,相对蛋白表达量与对照组比较差异无统计学意义(P<0.05),磷酸化的Chk1蛋白及p53蛋白表达逐渐增加,相对蛋白表达量与对照组比较差异有统计学意义(P<0.05)。结论:CTE显著抑制QBC939细胞增殖,诱导QBC939细胞凋亡,其可能机制与CTE调节凋亡相关蛋白表达,同时调节肿瘤细胞周期相关。  相似文献   
80.
Real-world predictors of the treatment efficacy of immune checkpoint inhibitors for hepatocellular carcinoma (HCC) are unknown. This retrospective study enrolled 87 consecutive patients with unresectable HCC from May 2017 to December 2019 at two hospitals. Of the 87 patients, 7, 9, 60, and 11 patients had Barcelona Clinic Liver Cancer stages A, B, C, and D, respectively, and 45, 30, and 10 patients were Child-Pugh class A, B, and C, respectively. The median injection numbers of nivolumab and treatment duration were 6 (3-8) and 2.53 (1.47-4.23) months, respectively, and 64.4% of patients received combination therapy. Radiological imaging was not assessed for 25 patients. Objective response (OR) and disease control rates were 19.5% and 39.1%, respectively. A single tumor (odds ratio: 9.542, P = .015) and ≥20% decline in serum α-fetoprotein protein (AFP) levels within the first 3 months of treatment (defined as AFP response, odds ratio: 5.997, P = .042) were predictors of OR. Lack of macrovascular invasion, combination therapy, and AFP response were predictors of progression-free survival. A Cancer of the Liver Italian Program (CLIP) score of 0-2 (hazard ratio [HR]: 3.717, P = .004) and grade 1-2 immune-related adverse events (irAEs, HR: 2.217, P = .049) were predictors of overall survival (OS) in the entire cohort, and a CLIP score of 0-2 (HR: 3.257, P = .009) was a predictor of OS in evaluable patients. IrAEs ≥ grade 3 were noted in 14 patients, and three died as a result. Having a single tumor and AFP response were predictors of OR, and CLIP score was a predictor of OS.  相似文献   
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