曲古抑菌素A对核移植供体细胞组蛋白H3乙酰化水平的影响

目的探讨组蛋白去乙酰化酶抑制剂曲古抑菌素A(TSA)对组蛋白H3乙酰化水平的影响,进而提高他们重编程的能力。方法用不同浓度的TSA处理胎儿成纤维细胞,应用免疫荧光和WesternBlot方法对细胞乙酰化水平进行量化分析。结果0.5nM,5nM,50nM和100nM浓度的TSA均引起供体成纤维细胞形态学的变化,对供体成纤维细胞组蛋白H3乙酰化有明显的剂量效应,随着TSA浓度增加,组蛋白H3乙酰化水平逐渐增加,在TSA浓度5nM时比0.5nM增加尤为明显。结论TSA能够提高胎儿成纤维细胞组蛋白H3乙酰化水平,提高核移植重编程的能力。     

动态监测TSA,LPO对低氧应激综合征的诊断价值

对环境低氧非习服者的总唾液酸（ＴＳＡ）及过氧化脂质（ＬＰＯ）进行动态监测发现，低氧环境非习服状态下，ＴＳＡ及ＬＰＯ水平均有明显上升，两者与低氧环境前比较均有极为显著性差异（Ｐ＜０．００１），且升高幅度与低氧应激反映的严重程度呈正相关，表明两项指标的变化不仅与低氧应激综合征的发生有关，亦可间接反映生物膜系统的损伤程度。因此，动态监测ＴＳＡ、ＬＰＯ水平对低氧应激综合征的诊断及治疗具有一定的指导意义。     

曲古抑菌素A阻断Stat3信号通路诱导前列腺癌细胞凋亡的实验研究

目的本实验研究组蛋白去乙酰化酶抑制剂曲古抑菌素A(TSA)对前列腺癌细胞DU145的抑制作用及其对信号传导与转录激活因子3(Stat3)信号通路的影响。方法采用不同浓度的TSA处理DU145不同时间后,四氮甲基唑蓝比色法测定TSA对细胞活力的抑制效应;流式细胞仪分析细胞周期的改变;蛋白印迹实验检测细胞凋亡相关蛋白半胱氨酸蛋白酶(Caspase)家族的Caspase-8、Caspase-9、Caspase-3、二磷酸腺苷核糖多聚酶(PARP)及Stat3信号蛋白活性(phospho-Stat3)的变化。结果 TSA时间和剂量依赖性地抑制DU145细胞的增殖,TSA处理细胞24 h和48 h后,细胞生存率分别是85.7%和68.7%;细胞经TSA处理后,细胞形态和细胞周期均发生明显的变化,细胞周期被阻断在G0/G1期,其细胞百分比从55.6%增加到68.5%;Western blot检测结果显示,TSA作用DU145细胞后,Stat3信号蛋白的磷酸化水平下降,同时IL-6对Stat3的刺激诱导作用也被TSA所阻断;Caspase-8、Caspase-9、Caspase-3、PARP等凋亡蛋白被TSA诱导活化,并发生显著剪切。结论 TSA能够通过抑制Stat3信号通路的活性来诱导DU145细胞凋亡。     

The development and clinical evaluation of second-generation leishmaniasis vaccines

Infection with Leishmania parasites results in a range of clinical manifestations and outcomes. Control of Leishmania parasite transmission is extremely difficult due to the large number of vectors and potential reservoirs, and none of the current treatments are ideal. Vaccination could be an effective strategy to provide sustained control. In this review, the current global situation with regard to leishmaniasis, the immunology of Leishmania infection and various efforts to identify second generation vaccine candidates are briefly discussed. The variety of clinical trials conducted using the only current second generation vaccine approved for clinical use, LEISH-F1 + MPL-SE, are described. Given that epidemiological evidence suggests that reducing the canine reservoir also positively impacts human incidence, efforts at providing a vaccine for leishmaniasis in dogs are highlighted. Finally, potential refinements and surrogate markers that could expedite the introduction of a vaccine that can limit the severity and incidence of leishmaniasis are discussed.     

Pancreatic carcinoma cells induce fibrosis by stimulating proliferation and matrix synthesis of stellate cells

BACKGROUND & AIMS: Tumor desmoplasia is one of the representative histopathologic findings in ductal pancreatic adenocarcinoma. The aims of this study were to examine the cellular and molecular mechanisms of fibrogenesis associated with pancreatic adenocarcinomas. METHODS: Immunostainings were performed with human pancreatic adenocarcinomas (n = 27) and tumors induced in nude mice (n = 36) by subcutaneously injecting MiaPaCa2, Panc1, and SW850 with and without pancreatic stellate cells. Matrix-producing cells were isolated from pancreatic adenocarcinomas and compared with pancreatic stellate cells isolated from tissue of chronic pancreatitis. Paracrine stimulation of pancreatic stellate cells by carcinoma cells was studied regarding matrix synthesis (collagen and c-fibronectin on protein and messenger RNA level) and cell proliferation (bromodeoxyuridine incorporation). RESULTS: High numbers of desmin and alpha-smooth muscle actin-positive cells were detected in 26 of 27 pancreatic adenocarcinomas. Intense fibronectin and collagen stainings were associated with these cells. By using cytofilament stainings, gene expression profiling, and morphological examinations, the matrix-producing cells obtained by the outgrowth method from pancreatic adenocarcinomas were identified as pancreatic stellate cells. Supernatants of MiaPaCa2, Panc1, and SW850 cells stimulated proliferation and collagen type I and c-fibronectin synthesis of cultured pancreatic stellate cells. Preincubation of the carcinoma cell supernatants with neutralizing antibodies against fibroblast growth factor 2, transforming growth factor beta 1, and platelet-derived growth factor significantly reduced the stimulatory effects. Subcutaneous injection of carcinoma cells and pancreatic stellate cells induced fast-growing subcutaneous fibrotic tumors in nude mice. Morphometric analysis of carcinoma cells (cytokeratin stainings) showed a high density of carcinoma cells in these tumors. CONCLUSIONS: Pancreatic stellate cells strongly support tumor growth in the nude mouse model. The increased deposition of connective tissue in pancreatic carcinoma is the result of a paracrine stimulation of pancreatic stellate cells by carcinoma cells.     

六味地黄丸(汤)联合二甲双胍治疗2型糖尿病的Meta分析和试验序贯分析

目的：系统评价六味地黄丸（汤）联合二甲双胍治疗2型糖尿病的有效性和安全性，为其临床应用提供依据。方法：系统检索中国期刊全文数据库（CNKI）、万方数据库（WanFang Data）、维普（VIP）、中国生物医学文献数据库（CBM）、PubMed、Embase、Cochrane Library，收集六味地黄丸（汤）联合二甲双胍治疗2型糖尿病的临床随机对照试验（RCT），检索时限均为建库至2018年9月，采用Cochrane风险评价表评价其研究质量，由2位研究者独立筛选文献、提取资料并评价纳入研究的偏倚风险，提取资料后通过RevMan 5.3.3软件进行Meta分析，Stata 12.0软件进行发表偏倚检验，TSA v 0.9软件进行试验序贯分析。结果：共纳入20个RCT包括2 018例患者。Meta分析结果显示：与对照组相比，试验组患者的有效率更高[RR=1.20，95% CI（1.13，1.28），P<0.000 01]，甘油三酯[MD=-0.35，95% CI（-0.42，-0.28），P<0.000 01]、糖化血红蛋白[MD=-0.77，95% CI（-1.03，-0.51），P<0.000 01]、低密度脂蛋白[MD=-1.12，95% CI（-1.20，-1.04），P<0.000 01]、血糖[MD=-1.17，95% CI（-1.57，-0.77），P<0.000 01]、空腹血糖[MD=-1.24，95% CI（-1.53，-0.94），P<0.000 01]、中医症状评分[MD=-0.83，95% CI（-1.13，-0.52），P<0.000 01]的降低均优于对照组，六味地黄丸汤剂联合二甲双胍对高密度脂蛋白的增高[MD=0.27，95% CI（0.11，0.43），P=0.000 8]、对总胆固醇的降低[MD=-1.34，95% CI（-1.42，-1.27），P<0.000 01]优于对照组。Egger检验提示可能存在发表偏倚，试验序贯分析提示六味地黄丸（汤）联合二甲双胍治疗2型糖尿病证据确切。结论：六味地黄丸（汤）联合二甲双胍治疗2型糖尿病疗效显著，且不良反应少，但纳入研究质量偏低，未来需要更严谨更大样本的研究以证实此结论。