全反式维甲酸对乳腺癌MCF-7细胞周期和增殖活性的影响及restin基因表达的初步研究

目的:检测全反式维甲酸(all-trans retinoic acid,ATRA)在乳腺癌MCF-7细胞周期、增殖、分化和凋亡过程中的作用,以及对。restin基因表达的影响,从而为研究其功能提供线索。方法:用流式细胞仪(FCM)检测细胞周期的变化;MTT 法检测细胞增殖活性;RT-PCR检测restin基因表达。结果:在ATRA诱导下,细胞出现G1期阻滞和生长抑制,增殖活性下降,restin基因开始表达,并呈增长趋势。结论:在ATRA诱导MCF-7细胞分化、凋亡过程中,ATRA能使MCF-7细胞 G1期阻滞,并能抑制MCF-7细胞生长,促使其凋亡,restin基因参与细胞周期的调控,特别是细胞凋亡。     

黄连素对乳腺癌细胞生长、迁移和放射敏感性的影响

目的 研究黄连素对乳腺癌细胞生长、迁移和放射敏感性的影响.方法 选取人乳腺癌细胞MDA-MB-231和MCF-7,用MTT法检测细胞的生长和增殖;划痕愈合法观察细胞迁移能力;细胞流式技术测定细胞周期改变;磷脂酰丝氨酸外翻分析法检测细胞凋亡;Western blot法测定蛋白表达水平;细胞克隆形成法观察黄连素与辐射的联合作用.结果 黄连素明显抑制人乳腺癌MCF-7和MDA-MB-231细胞的生长,并显现剂量-效应和时间-效应关系,MCF-7和MDA-MB-231细胞对黄连素表现出同样的敏感性.黄连素可以诱导剂量依赖性的G0/G1期细胞阻滞,40 μmol/L的黄连素处理后MDA-MB-231和MCF-7细胞早期凋亡分别高达86.63％和66.62％,与未处理的对照组相比,差异均有统计学意义(t=75.15和43.75,P＜0.01).黄连素明显降低了细胞周期调节相关蛋白Cyclin B1和抑凋亡蛋白Bcl-2的表达水平,而增加了促凋亡蛋白Bax和Caspase-3的表达水平,但不影响细胞周期调节蛋白Cyclin D1的表达水平.低剂量(≤5μmol/L)黄连素可以明显降低细胞的迁移能力.采用单靶多击模型拟合曲线发现,与单独照射组相比,5 μmol/L黄连素预处理4h后MDA-MB-231细胞和MCF-7细胞的辐射增敏比分别为1.12和1.22.结论 黄连素通过调节细胞凋亡和细胞周期阻滞抑制乳腺癌细胞生长和迁移,并可提高乳腺癌细胞的放射敏感性.     

LRP16通过增强ERα介导的转录激活活性促进乳腺癌MCF-7细胞增殖

目的:探讨LRP16基因促进MCF-7细胞增殖的分子生物学机制。方法:(1)将ERα模式启动子调控的荧光素酶报告子(3×ERE-Luc)与ER,αLRP16真核表达载体共转染MCF-7细胞,测定3×ERE-Luc的相对荧光素酶活性;(2)将3×ERE-Luc,ERα真核表达载体、针对LRP16的小干扰RNA(LRP16-siRNA374,LRP16-siRNA668)或对照小干扰RNA(control-siRNA)共转染MCF-7细胞,测定3×ERE-Luc的相对荧光素酶活性;(3)用Northern印迹与W estern印迹方法检测抑制LRP16基因后MCF-7细胞中ERα下游靶基因对雌激素刺激的反应性。结果:(1)LRP16增强3×ERE-Luc的相对荧光素酶活性,并呈现剂量依赖性,该效应依赖于雌激素对ERα的激活;(2)North-ern印迹结果显示,抑制LRP16表达限制了雌激素对ERα下游靶基因表达水平的刺激上调,包括E2F1、视黄酸受体(RARα)、c-fos和MTA3,但没有影响组织蛋白酶D(cathepsin D)的反应性;W estern印迹结果显示,抑制LRP16限制了雌激素对细胞周期蛋白D1(cyc lin D1)的刺激。结论:(1)雌激素反应性靶基因LRP16反馈增强ERα介导的转录激活活性;(2)LRP16基因通过增强ERα介导的转录激活活性调节其下游靶基因的表达,主要通过改变cyc linD1的水平促进MCF-7细胞的增殖。     

HLH缺失型Id2候选相互作用蛋白

目的:筛选可以与螺旋-环-螺旋(HLH)结构域缺失的Id2相互作用的蛋白.方法:用重叠延伸PCR方法将Id2中的HLH结构域缺失,并插入到pGBKT7载体,构建 BD∶ Id2-DBM-δHLH融合诱饵质粒;构建MCF-7细胞的ds cDNA文库;采用共转化方法进行Id2-DBM-δHLH相互作用蛋白的酵母双杂交筛选,采用PCR方法扩增阳性克隆中的AD∶ cDNA序列并测序;将获得的AD∶ cDNA质粒分别与BD∶ Id2-DBM-δHLH诱饵质粒共转化酵母进行配对验证.结果:酵母双杂交方法共筛选到19个阳性克隆,PCR方法在这19个克隆中共扩增到28条片段,序列测定证实含18个不同的基因,对其中的13个进行配对验证后证实了其中8个与HLH缺失型Id2相互作用,这8个基因分别是:UXT、VIM、KRT7、FHL2、SEI1、PCBP1、SIVA和LSM2.结论:本研究首次利用HLH缺失型Id2作为诱饵,利用酵母双杂交技术筛选识别了一族新的Id2相互作用蛋白,为进一步研究Id2的功能调控以及非HLH依赖的功能活性奠定基础.     

尿多酸肽对乳腺癌细胞周期蛋白D1表达的影响

目的研究肿瘤细胞分化诱导剂尿多酸肽（CDA-Ⅱ）对乳腺癌细胞周期蛋白D1（cyclin D1）表达的影响。方法将CDA-Ⅱ与不同生物学特性的乳腺癌细胞株MCF-7和MDA-MB-231进行体外培养,同时以维甲酸为阳性对照,观察CDA-Ⅱ对乳腺癌细胞生长曲线、cyclin D1表达等方面的影响。结果CDA-Ⅱ可减缓两株乳腺癌细胞的生长和增殖能力,减少乳腺癌细胞cyclin D1表达。结论CDA-Ⅱ可抑制不同生物学特性的两株乳腺癌细胞的生长和增殖能力,减少乳腺癌细胞cyclin D1表达,为CDA-Ⅱ治疗乳腺癌提供了实验依据。     

分化抑制因子1促进血管内皮细胞增殖的机制研究

目的探讨分化抑制因子1(Id1)促进血管内皮细胞增殖的机制。方法构建p21启动子介导的报告基因p21-Luc,分别转染Eahy926细胞、Id1抑制(siId1细胞)或诱导表达(pcDNAId1)细胞、E2A抑制或诱导表达细胞,检测荧光素酶报告基因活性。提取Eahy926细胞总蛋白,分别加入Id1抗体、E12抗体和E47抗体,免疫共沉淀,以Eahy926细胞作为对照,Western blotting检测Id1、E12和E47的表达情况。分别转染siId1、pcDNAId1载体于Eahy926细胞,与正常Eahy926细胞同步化培养48h后,行细胞染色,用流式细胞仪检测细胞G1期的DNA含量。结果与Eahy926细胞比较,siId1细胞、pcDNAE2A细胞p21基因启动子介导的荧光素酶活性增强,p21蛋白表达增高(P<0.05,P<0.01);pcDNAId1细胞、siE2A细胞p21基因启动子荧光素酶活性降低,p21蛋白表达减弱(P<0.05)。免疫共沉淀结果显示,Id1免疫共沉淀细胞裂解物中同时检测到E47/E12蛋白,E47/E12沉淀物中也能检测到Id1。与正常Eahy926细胞比较,转染siId1的...     

CDA-Ⅱ对乳腺癌细胞生长抑制作用的可逆性实验研究

目的 研究癌细胞分化诱导剂尿多酸肽（CDA-Ⅱ）对乳腺癌细胞生长的抑制作用是否具有可逆性.方法 将CDA-Ⅱ与乳腺癌细胞株MCF-7和MDA-MB-231进行体外培养,然后去除培养液中的CDA-Ⅱ,再观察其对乳腺癌细胞生长曲线、细胞周期及形态学等方面的影响.结果 去除CDA-Ⅱ后,乳腺癌细胞的生长和增殖能力增加,乳腺癌细胞S期比例增加.结论 CDA-Ⅱ对乳腺癌细胞生长和增殖的抑制能力具有可逆性.     

siRNA表达载体对MCF-7细胞生长及其hTERT基因表达抑制的研究

目的构建人端粒酶反转录酶(hTERT)基因的RNA干扰(RNAi)表达载体,探讨该载体对人乳腺癌MCF-7细胞生长及hTERT基因表达的影响。方法设计针对hTERT基因的干扰靶序列,构建siRNA重组表达质粒pGenesil-hTERT,将该质粒酶切测序鉴定后,以脂质体转染MCF-7细胞,RT-PCR和Western blot技术分别检测hTERT基因及其蛋白的表达,MTT法观察转染后MCF-7细胞生长情况。结果酶切电泳和测序分析表明插入序列正确,重组质粒构建成功。该质粒转染MCF-7细胞后,hTERT基因mRNA和蛋白质的表达水平均显著降低,MCF-7细胞生长抑制。结论内源性短发夹状siRNA能有效抑制hTERT基因的表达,进而抑制乳腺癌MCF-7细胞的增殖生长,这也为肿瘤的基因治疗提供了实验依据。     

BRCA1对FHL2转录激活功能的影响

目的：进一步了解乳癌易感基因BRCA1与FHL2相互作用对FHL2转录激活功能的影响，为揭示BRCA1在肿瘤发生发展中的作用提供依据。方法：将BRCA1 C端缺失突变体BRCA1(△1443—1863aa)和BRCA1(△908，1863aa)按正确读框插入到pCR3载体中，并在293T细胞中表达。利用GAL4荧光素酶报告基因检测野生型BRCA1以及肿瘤易感突变体BRCA1(P1749R)，BRCA1(Y1853imA)，BRCA1(△1443—1863aa)和BRCA1(△908，1863aa)对FHL2转录激活活性的调节作用。结果：野生型BRCA1能增强FHL2转录激活活性，且具有剂量依赖性。而4种肿瘤易感突变体增强FHL2转录激活活性的能力明显减弱。结论：BRCA1与FHL2相互作用可能对基因转录调节以及肿瘤发生、发展中起着重要作用。     

Syk表达对乳腺肿瘤细胞侵袭迁移作用的影响

目的:探讨脾源性酪氨酸激酶(spleen tyrosine kinase, Syk)在人乳腺癌细胞中的表达及其对肿瘤细胞侵袭迁移能力的影响.方法:RT-PCR法、免疫荧光法检测不同侵袭能力乳腺癌细胞株--MCF-7(低侵袭性)和MDA-MB-231(高侵袭性) Syk mRNA及蛋白的表达;采用脂质体介导的方法,将Syk基因导入Syk(-)乳腺癌细胞株,利用Transwell小室法检测Syk基因对肿瘤细胞侵袭迁移能力的影响.结果:Syk mRNA及蛋白在MCF-7细胞中呈中等程度表达,在MDA-MB-231中表达缺失;转染Syk基因的MDA-MB-231细胞与转染空载体及未转染MDA-MB-231细胞相比,侵袭及迁移实验中的穿膜细胞数(总迁移细胞数/5HPF)均明显减少(P＜0.05).结论:Syk表达可降低乳腺肿瘤细胞体外侵袭迁移能力.     

Optimization of the system of medical service of students of Cadet Schools of the Ministry of Defense of the Russian Federation

One of the factors of the successful military career guidance Cadet schools students is preserving and promoting their health. Medical support of children and adolescents aged 10-17 years should include the full range of medical and preventive measures defined for this group. The state of providing outpatient care for pupils at the Cadet School in St. Petersburg was studied. These results show that full medical care in accordance with the standards can be based only on children's health clinics. It is important that the organization of medical support pupils cadet schools should be cooperate with civilian health care.     

带状疱疹83例误诊原因分析

带状疱疹是由水痘—带状疱疾病毒引起的皮肤科常见疾病。其主要的病理损害,一是受累神经的严重炎症性浸润,继而导致受侵犯神经节内神经细胞变性、坏死;二是皮肤的水泡。迅速抑制神经节和相应的感觉神经纤维的充血、水肿和坏死,防止粘连形成,达到迅速镇痛、改善皮损,缩短病程及防止后遗症的发生是治疗的关键。因而,尽早明确诊断,     

Estimation of accumulated dose of radiation by method of ESR-spectrometry of dental enamel of mammals

ESR-spectrometry was used to investigate radiation-induced paramagnetic centers in enamel of mammals: carnivores (polar bear and fox), ungulates (reindeer, European bison, moose), and man. Values at half the microwave power saturation of the radiation signal, P_1/2, evaluated at room temperature, was found to range from 16 to 26 mW for animals and man. A new approach to discrimination of the radiation induced signal from the total ESR spectrum of reindeer enamel is proposed. ‘Dose-response’ dependencies of enamel of different species mammals were measured within the dose range from 0.48 up to 10.08 Gy. Estimations of ‘radiosensitivity’ enamel of carnivores and ungulates showed good agreement with radiosensitivity enamel of man by ESR method.     

Analysis of the results of the international comparison of activity measurements of a solution of Fe

The results of an international comparison of activity measurements of a solution of ⁵⁵Fe organized by the BIPM in 2005 are reported and analysed. This exercise, which follows the procedures of the CIPM mutual recognition arrangement to update older comparisons, is a renewal of the comparison organized by the BIPM that took place in 1978. A EUROMET comparison was organized in 1996 specifically to compare activity measurements of a ⁵⁵Fe solution by means of liquid-scintillation techniques. Results of these three comparisons are presented and discussed in this paper.

The radionuclide solution was provided by the NPL, which also distributed the samples to the participants. The activity of the ampoules was measured by 16 laboratories using 12 methods producing 25 results. Some general considerations on uncertainty assessments pertaining to the different techniques used are drawn. The outcome of four different estimators is compared from which the presence of at least one outlier can be confirmed. Further measurements should be made to try to reduce the discrepancy between the results. To date the outcome of the present comparison does not show an improvement to that of the 1996 comparison.     

Evaluation of the results of various technics of non-surgical therapy of varicocele

A new method of non-surgical treatment of varicocele syndrome is described: it consists in sclerotherapy of spermatic vein by trans-femoral percutaneous catheterization with balloon-catheters. In 8 cases venous thrombosis has been induced by direct electric clotting. The techniques and a 6 months follow-up are discussed. It is pointed out that this procedure should be considered as the method of choice for tubular lesions and sub-fertility prophylaxis in young people and in childhood.     

延迟性脾破裂误漏诊原因分析

目的探讨延迟性脾破裂误漏诊原因和预防措施.方法回顾性分析总结12例延迟性脾破裂中的诊断和误漏诊的经验与教训.结果本组延迟性脾破裂的误漏诊5例(41.66%).对多发伤与脾破裂并存可能认识不足,外伤史轻微或伤员隐瞒外伤史,缺乏腹痛-缓解-突然再腹痛的典型病史,缺乏“对冲性脾破裂”力学分析和整体化诊断思路等为其误漏诊的主要原因.结论详细的外伤史和全面系统检查,重视腹以外多发伤掩盖腹内脏器伤及延迟性脾破裂可能.确立外伤-腹内脏器伤-脾破裂整体化诊断思路.不间断地辅以B超检查脾形态学变化和腹内有无积液,腹腔穿刺确定有无血腹、X线胸腹部检查观察左侧胸肋角和膈肌运动情况、必要时CT检查以尽早发现脾包膜下血肿,降低延迟性脾破裂误漏诊率.