人端粒酶亲和纯化方法的建立及其初步鉴定

建立一种亲和纯化人端粒酶的手段,方法酶切鉴定人端粒酶ＲＮＡ质粒,所切下的ｈＴＲｃＤＮＡ片段用生物素标记后与链霉亲和素琼脂糖珠耦连,用高端粒酶活性的胃肿瘤细胞提取液与之反应,利用端粒酶核糖核蛋白的特性,形成链霉亲和素琼脂糖珠－生物素标记ｈＴＲｃＤＮＡ－ｈＴＲ－端粒酶蛋白组份复合物,核酸解离液洗脱后获得亲和纯人端粒酶。     

尿苷三磷酸通过PTEN/Vimentin抑制胃癌细胞的侵袭

目的 研究尿苷三磷酸(uridine triphosphate,UTP)对胃癌细胞迁移和侵袭的影响及其分子机制.方法 采用细胞划痕实验检测UTP对胃癌细胞MKN-45和SGC-7901迁移能力的影响;Transwell检测UTP对正常人胃黏膜细胞GES-1和胃癌细胞MKN-45、SGC-7901侵袭能力的影响;Western blot检测UTP对胃癌细胞MKN-45和SGC-7901 PTEN磷酸化水平及Vimentin表达的影响.结果 细胞划痕实验表明UTP组抑制胃癌细胞MKN-45和SGC-7901迁移(P＜0.05).Transwell实验结果显示UTP组抑制胃癌细胞MKN-45和SGC-7901侵袭(P＜0.01),但对正常人胃黏膜细胞GES-1无影响(P＞0.05).Western blot实验证实UTP组可增强胃癌细胞MKN-45和SGC-7901 PTEN磷酸化水平,同时下调Vimentin的表达.结论 UTP抑制胃癌细胞的迁移和侵袭,可能是与其上调PTEN磷酸化水平,抑制Vimentin表达有关.     

抗肿瘤转移肝素酶特异性抗体的筛选及鉴定

目的通过鉴定制备的人肝素酶单克隆抗体,筛选出具有抗肿瘤转移特异性的单克隆抗体株,并大量制备.方法采用Western blot技术,以HepG2、SGC-7901、MKN45、SW480、U2OS、MCF-7细胞总蛋白为样本,对已制备的3株人肝素酶单克隆抗体进行初步鉴定,筛选出能够与肝素酶蛋白特异性结合的抗体,并采用免疫细胞化学技术进一步验证筛选出的抗体特异性,然后通过Transwell体外侵袭实验观察筛选出的肝素酶单克隆抗体对肿瘤转移的抑制作用.结果已制备的3株人肝素酶单克隆抗体均能与不同肿瘤细胞肝素酶蛋白结合,其中12号抗体与商品化肝素酶单克隆抗体在MCF-7细胞中均检测出肝素酶弱阳性表达,其特异性最佳;免疫细胞化学结果也显示在SGC-7901、HepG2、MKN45、SW480和U2OS细胞中12号抗体能检测出肝素酶阳性表达,而在MCF-7细胞中检测出肝素酶弱阳性表达;Transwell体外侵袭实验结果显示12号抗体(100 μg,浓度约1 mg/ml)作用于SGC-7901、HepG2、MKN45、SW480和U2OS细胞48 h后,其穿膜细胞数与正常小鼠IgG对照组相比明显减少(P<0.05).结论纯化制备的人肝素酶单克隆抗体能够与肿瘤细胞表达的肝素酶蛋白特异性结合,并通过抑制肝素酶蛋白达到抑制肿瘤细胞的扩散与转移.     

氨基糖甙类药物毒性对耳蜗内毛细胞传入神经突触后谷氨酸受体的影响

目的 探讨氨基糖甙类耳毒性药物暴露下小鼠内毛细胞传入神经突触后谷氨酸受体表达水平的变化,以及这种变化和小鼠听功能改变之间的关系。方法 选择5周大小的C57BL/6J小鼠,每天腹腔注射庆大霉素1次,药物浓度为100mg/kg,连续给药14d,分别在第7天、第14天时检测受试小鼠的ABR(Click&Tone burst),并以未进行腹腔注射给药的小鼠(0d)作为对照组。使用抗GluR2/3抗体对小鼠基底膜铺片标本进行染色标记,以观察耳蜗内毛细胞传入神经突触后谷氨酸受体(GluR2/3)的表达情况。结果 注射庆大霉素小鼠在第7天、10天、14天时听力损失明显,听力阈值显著高于对照组(p<0.05)。应用庆大霉素后第7天和14天,耳蜗内毛细胞传入神经突触后谷氨酸受体(GluR2/3)的表达水平和对照组相比显著增高,听力损失最为严重,提示GluR2/3在突触后的过高表达和耳聋程度存在相关性。结论 氨基糖甙类耳毒性药物持续暴露可以造成耳蜗内毛细胞传入神经突触间隙内谷氨酸递质过表达,与耳聋程度呈正相关。     

胃息肉与幽门螺杆菌感染相关性研究

目的研究胃息肉与幽门螺杆菌(Hp)感染的相关性。方法选取胃息肉患者150例作为观察组,另外,选取慢性胃炎患者150例作为对照组;观察组每例息肉均作做检,记录病理类型,并取周围黏膜即胃窦大、小弯,前、后壁4个部位(距幽门约2~5cm处)做病理检查,观察黏膜炎症程度,并将息肉组织及周围黏膜组织分别作切片经改良吉姆萨(Giemsa)染色法镜检找Hp,观察息肉部位与周围黏膜Hp感染情况;对照组分别在胃窦大、小弯,前、后壁4个部位各取一块组织活检找Hp,并作病理,观察慢性胃炎患者Hp感染率。结果观察组150例,Hp感染率58.0%(87/150),感染强度以中低强度为主,其中息肉部位HP感染率39.3%(59/150),非息肉部位HP感染率42.0%(63/150)。增生性息肉102例(68.0%),Hp感染率63.7%(65/102);胃底腺息肉31例(20.7%),Hp感染率38.7%(12/31);炎性息肉14例(9.3%),Hp感染率57.1%(8/14);腺瘤性息肉3例(2.0%),Hp感染率66.7%(2/3)。单发息肉93例(62.0%),多发息肉57例(38.0%),息肉以胃底体多见,其中增生性息肉在胃底体发生率94.1%(96/102),胃底腺息肉在胃底体发生率87.1%(27/31),增生性息肉Hp感染率显著高于胃底腺息肉(P<0.05),且以中高强度Hp感染为主,增生性息肉胃黏膜炎症活动性发生率较高,同时伴有黏膜肠化、萎缩。慢性胃炎对照组150例,Hp感染率52.0%(78/150),结果显示胃息肉发生与Hp感染之间无明显相关性。结论胃息肉发生与Hp感染无显著相关性;但胃息肉类型与Hp感染率和感染强度相关,其中增生性息肉Hp感染率和感染强度均显著高于胃底腺息肉。     

哺乳动物前庭毛细胞再生的研究进展

自从在鸟类等非哺乳脊椎动物中发现毛细胞再生至今已近20年,人们对毛细胞再生的研究已经取得了丰硕的成果,而且有可能从实验性研究向临床应用性研究方面发展.目前内耳毛细胞再生方面的研究,尤其是新生毛细胞的前体细胞和再生机制的探索正方兴未艾,本文对此作一综述.     

充分发挥住院总医师作用 做好进修生的管理工作

住院总医师作为主任的助手。参与科室日常的医疗，教学及管理工作，进修生的管理是住院总医师工作的一项主要内容。充分发挥住院总医师的作用，做好进修医生的管理工作，对搞好全科医疗工作，减少医疗事故，提高科室管理水平起着重要作用。     

HCCR-2反义核酸对肝癌HepG2细胞的作用

Objective To investigate the effects of antisense recombinant euraryotic expression vector of HCCR-2 on the proliferation and apoptosis of HepG2. Methods The antisense recombinant eukaryotic expression vector of HCCR-2 was constructed. The vector was stably transfected to the HepG2 cells, and positive clones were selected by G418 (antiseuse vector group), pIRES2-EGFP vector was transfected into the HepG2 cells in the same way (pIRES2-EGFP group). The conditions of the nontransfected HepG2 cells were used as control (HepG2 group). Changes in cell growth curve, cell cycle, cell apoptosis and morphology of HepG2 cells after the transfec-tion were detected by MTT method, flow cytometry and transmission electron microscopy, respectively. All the data were analyzed by one-way ANOVA and chi-square test. Results The expression level of HCCR-2 mRNA was down-regulated to 0.39±0.04 in antisense vector group, and the expression level of HCCR-2 mRNA in pIRES2-EGFP group and HepG2 group were 0.62±0.06 and 0.72±0.03, respectively, with significant difference among the 3 groups (F=43.701, P<0.05). The apoptotic rate of HepG2 cells in antisense vector group, pIRES2-EGFP grop and HepG2 group were 13.30%, 2.51% and 2.07%, respectively, with significant difference among the 3 group (χ2=6.793, 8.721, P<0.05). The growth of HepG2 cells in antisense vector group was retarded, and was blocked in G0/G1 stage. Conclusions The HCCR-2 antisense recombinant eukaryotic expression vector can inhibit the mRNA expression of HCCR-2 and promote the apoptosis of cells. HCCR-2 may be involved in cell regulation and the proliferation of hepatocellular carcinoma cells.     

Infrequent microsatellite instability mutator phenotype in Chinese hepatocellular carcinomas

Objective: In order to elucidate the molecular mechanisms that might be responsible for hepatocarcinogenesis, we examined microsatellite instability (MSI), mismatch repair gene hMLH1 mutation and methylation in hepatocellular carcinoma. Methods: Fifty-two cases of surgically resected sporadic hepatocellular carcinoma (HCC) were studied, hMLH1 mutation was examined by two-dimensional electrophoresis and DNA sequencing; hMLH1 methylation was determined by methylation-specific PCR (MSP); and MSI at BAT26 was analyzed by PCR-based methods. Results: MSI at BAT26 was found in 3 of 52 cases (5.8%) of the tumors analyzed. No hMLH1 mutation or hypermethylation was found in these 52 cancerous tissues. No correlation existed between MSI and clinico-pathological characteristics of the patients. Conclusion: Our results suggest that MSI at BAT26 is rarely associated with carcinogenesis of chinese HCC. The genesis of sporadic HCC may occur in an alternative pathway that is probably different from MSI pathway.     

采用“分区定位法”进行妇女透环

一般常规检查子宫环,多用站立位透视.根据环的位置分为左、中、右.由环与耻骨联合上缘的距离,以实际厘米数为单位而作出诊断.如:左1,左2,左3,左4等.如有异常情况则结合卧位进行检查.若更为简便则用划“+”打“×”来表示,如:“（?）”或“(?)”等.笔者在实际工作中、考虑到农村的放射科工作,