Inhibition on Telomerase Activity and Cytotoxic Effects by Cisplatin in Cultured Human Choroidal Melanoma Cells

Purpose: To study the changes of telomerase activity and cytotoxic effects by Cisplatin; cis-dichlorodiamine platinum (CDDP) in cultured human choroidal melanoma. Material and Methods: The primary cultured human choroidal melanoma cells were cultured in the presence and absence of CDDP with different concentration and time respectively. The toxic effects were evaluated by MTT and the level of telormarse was detected by PCR-ELISA assay. And the relationship between telomerase activity and cytotoxic effects were analyzed by a correlation analysis.Results: Following the increase of the concentration and the time of CDDP, gradually repressed telomerase activity was detected in cultured cells. Meanwhile, the restrain rate of the cells increased. The telomerase activity at 24h and 1μg/ml was repressed significantly compared with the control cells. However, the appearance of cell death lagged behind the decreasing of telomerase.Conclusions: CDDP is an effective telomerase inhibitor in cultured choroidal melan     

cGAS-STING通路介导酸性去氧胆酸诱导人正常食管上皮细胞炎症的机制研究

目的：探讨酸性去氧胆酸（deoxycholic acid,DCA）诱导人正常食管上皮细胞（human esophageal epithelial cell,HEEC线粒体DNA(mitochondrial DNA,mtDNA)损伤及释放与环岛苷酸-腺苷酸合酶-干扰素基因刺激蛋白（cyclic GMP-AMP synthase-stimulation of interferon gene,cGAS-STING）通路在食管上皮炎症发生发展中的关联。方法：将HEEC分为对照组和酸性DCA处理组。CCK-8法检测细胞存活率;荧光显微镜及流式细胞术检测活性氧（reactive oxygen species,ROS）、线粒体活性氧（mitochondrial reactive oxygen species,mtROS）及线粒体膜电位（mitochondrial membrane potential,MMP）的变化;化学发光法检测三磷酸腺苷（adenosine triphosphate,ATP）水平;透射电镜观察线粒体超微结构改变;RT-qPCR检测mtDNA拷贝数变化;Western blot检测...     

Hair cell loss and regeneration after severe acoustic overstimulation in the adult pigeon

The extent of hair cell regeneration following acoustic overstimulation severe enough to destroy tall hair cells, was determined in adult pigeons. BrdU (5-bromo-2′-deoxyuridine) was used as a proliferation marker. Recovery of hearing thresholds in each individual animal was measured over a period of up to 16 weeks after trauma. In ears with loss of both short and tall hair cells, little or no functional recovery occurred. In ears with less damage, where significant functional recovery did occur, there were always a few rows of surviving hair cells left at the neural edge of the basilar papilla. In the region of hair cell loss, numerous BrdU labeled cells were found. However, only a small minority of these cells were regenerated hair cells, the majority being monolayer cells. Irrespective of the extent of the region of hair cell loss, regenerated hair cells were observed predominantly in a narrow strip at the transition from the abneural area of total hair cell loss and the neural area of hair cell survival. With increasing damage this strip moved progressively towards the neural edge of the papilla. No regeneration of hair cells was observed in the abneural region of total hair cell loss, even up to 16 weeks after trauma. The results indicate that there is a gradient in the destructive effect of loud sound across the width of the basilar papilla, from most detrimental at the abneural edge to least detrimental at the neural edge. Both tall and short hair cells can regenerate after sound trauma. Whether they do regenerate or not depends on the degree of damage to the area of the papilla where they normally reside. Regeneration of new hair cells occurs only in a narrow longitudinal band, which moves from abneural into the neural direction with increasing damage. In the area neural to this band, hair cells survive the overstimulation. In the area abneural to this band, sound damage is so severe, that no regeneration of hair cells occurs. As a consequence morphological and functional deficits persist.     

综合医院应对危机和突发公共卫生事件的探讨

各种各样的灾难对人类造成的危害与日俱增,综合医院如何应对危机和突发公共卫生事件是一个新的课题.就危机和突发公共卫生事件发生医院可能遇到的问题,如何增强危机意识,构建现代危机和突发公共卫生事件管理体系,努力培养医学救治队伍等问题进行了探讨.     

自卫颗粒抗胃黏膜损伤作用的实验研究

近年来加强胃黏膜防御功能的研究越来越受到国内外的重视.本实验通过预先给予大鼠灌服自卫颗粒,并与思密达作对照,观察自卫颗粒对大鼠胃黏膜损伤的预防保护作用,同时从表皮生长因子(EGF)、前列腺素E2(PGE2)角度探讨其可能的作用机理.     

菟丝子生品及3种炮制品中总黄酮含量的比较研究

目的：建立菟丝子总黄酮含量测定方法,并比较生品及3种炮制品的总黄酮含量。方法：采用紫外分光光度法,以金丝桃苷为对照品,建立菟丝子总黄酮的含量测定方法,并用此方法测定生品及3种炮制品的总黄酮含量。结果：建立了菟丝子总黄酮的含量测定方法,用此方法测定菟丝子生品中的总黄酮含量为1.68%,清炒品为2.26%,酒炙品为2.27%,盐炙品为2.22%。结论：本方法简便、准确,适合于菟丝子总黄酮含量的测定,菟丝子炮制后的总黄酮含量较生品有了显著升高,其中酒炙品升高最多。     

LED固化灯光照强度对光固化复合树脂聚合收缩的影响

目的采用数字图像相关法动态研究LED光固化灯不同光照强度对光固化复合树脂聚合收缩的影响。方法收集12颗大小接近的新鲜离体磨牙,随机分为3组,制备大小为2.0 mm×2.0 mm×2.0mm的邻(?)面洞形,洞面酸蚀冲洗后涂粘接剂光照10 s,充填3M Z350纳米复合树脂,邻面快速制造散斑,LED固化灯垂直(?)面光照40s,3组光照强度分别为300 mW/cm~2、500 mW/cm~2和800 mW/cm~2,数码相机同步实时采集光照过程中试件表面散斑的变化序列图像,用数字图像相关法计算获得各序列图上逐个像素点水平方向(x)和垂直方向(y)位移,统计线性收缩率,描绘各像素点的时域变化曲线,并用SPSS 12.01统计软件包进行方差分析和配对t检验。结果 3种光照强度下树脂x方向线收缩率分别为0.081%～0.486%、0.004%～0.316%和0.063%～0.560%,y方向线收缩率分别为0.088%～0.981%、0.003%～0.77%和0.157%～1.252%,3组之间差异有统计学意义(P<0.05);3组第20 s树脂游离面收缩x方向位移差异无统计学意义,y方向位移差异有统计学意义。结论 LED光固化灯500 mW/cm~2光照时引起的树脂聚合收缩最小。     

不同TNM分期标准在胃癌患者预后评估中的价值

背景:胃癌合理分期对选择患者的治疗方案、判断疗效以及预后评估等均具有重要的指导意义。目的:探讨第6版和第7版胃癌TNM分期标准在胃癌患者预后评估中的价值。方法:收集955例有完整临床病理和随访资料的胃癌病例,应用第6版和第7版TNM分期标准分别对其预后进行评估,以Kaplan-Meier生存分析比较这两种标准对胃癌患者预后的评估价值。结果:按第6版TNM分期标准,Ⅰ期209例（21.9%）、Ⅱ期147例（15.4%）、Ⅲ期300例（31.4%）和Ⅳ期299例（31.3%）;按第7版分期标准,Ⅰ期168例（17.6%）、Ⅱ期170例（17.8%）、Ⅲ期569例（59.6%）和Ⅳ期48例（5.0%）。两种分期的Ⅲ、Ⅳ期患者的生存时间均显著低于Ⅰ、Ⅱ期（P<0.05）。第6版Ⅲ_A期患者在第7版中分为Ⅲ_A期和Ⅲ_B期,两者之间生存时间相比差异有统计学意义（P<0.05）;第6版Ⅳ期患者在第7版中分为Ⅲ_B、Ⅲ_c、Ⅳ期,这三组的生存时间相比差异有统计学意义（P<0.05）。在第7版分期中,肿瘤侵及邻近结构(T_4B)患者的生存时间较穿透浆膜层（T4A）的患者明显缩短（P<0.05）;N₁期和N₂期患者生存时间相比差异有统计学意义（P<0.05）。结论:第6版TNM分期标准相对简易,对胃癌患者预后评估有一定价值;第7版TNM分期标准进一步细分,更能精确判别胃癌的生物学行为,对晚期胃癌患者的准确判断以及术后辅助治疗具有重要指导作用。     

腺病毒介导BMP-2联合低氧诱导因子1α突变型与单基因BMP-2分别转染BMSCs后成骨效应的比较研究

目的比较腺病毒载体Ad-BMP-2-内部核糖体进入位点(internal ribosome entry site,IRES)-低氧诱导因子1α突变型(hypoxia inducible factor 1αmu,HIF-1αmu)与Ad-巨细胞病毒(cytomegalovirus,CMV)-BMP-2-IRES-人源化海肾绿色荧光蛋白1(human renilla reniformis green fluorescent protein 1,hrGFP-1)分别转染BMSCs后的成骨效应,优化成骨细胞种子来源。方法取1月龄新西兰大白兔骨髓分离培养BMSCs。取第3代BMSCs进行病毒液转染,根据转染病毒液不同将实验分为4组,A、B、C组分别采用感染复数(multiplicity of infection,MOI)为50、100、150和200的Ad-BMP-2-IRES-HIF-1αmu、Ad-CMV-BMP-2-IRES-hrGFP-1、Ad-CMV-IRES-hrGFP-1(空腺病毒载体)转染细胞,D组为未被转染的BMSCs。选择最佳MOI值进行观察。转染后采用免疫组织化学染色检测BMP-2表达,Western blot检测BMP-2和HIF-1α蛋白表达,ALP活性测定和钙结节茜素红染色检测细胞成骨分化能力。结果 A、B、C组最佳MOI值分别为200、150和100。免疫组织化学染色示,A、B组BMP-2染色呈阳性,C、D组呈阴性;A组阳性细胞数明显多于B组(P<0.05)。Western blot检测示,A、B组BMP-2蛋白表达明显高于C、D组(P<0.05),A组高于B组(P<0.05);A组HIF-1α蛋白表达明显高于其余3组(P<0.05),其余3组间差异无统计学意义(P>0.05)。A、B组ALP活性明显高于C、D组(P<0.05),A组高于B组(P<0.05)。茜素红染色示,A、B组可见明显钙结节,C、D组未见钙结节形成;且A组钙结节数量多于B组(P<0.05)。结论单载体双基因Ad-BMP-2-IRES-HIF-1αmu与单载体单基因Ad-CMV-BMP-2-IRES-hrGFP-1分别转染兔BMSCs后,前者BMP-2和成骨效应表达均高于后者。