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1.
三氧化二砷对人结肠癌细胞增殖及凋亡影响的研究   总被引:5,自引:0,他引:5  
目的:观察三氧化二砷(As2O3)对人结肠腺癌LS-174T细胞增殖的抑制及凋亡的诱导作用。方法:应用MTT法、细胞集落形成试验、流式细胞仪技术和TUNEL法观察不同浓度的As2O3(1.0μmol,2.0μmol,4.0μmol,8.0μmol,16.0μmol/L)对LS-174T细胞增殖和凋亡的影响。免疫组化技术观察As2O3对bcl-2基因表达的影响。结果:LS-174T细胞经As2o3作用后,细胞生长抑制率上升,细胞集落形成率下降,细胞周期中G1期细胞比例上升,S期和G2/M期细胞比例下降,TUNEL法显示凋亡细胞数增加,免疫组化结果显示bcl-2的表达明显减弱。结论:As2O3能抑LS-174T细胞增殖并诱导该细胞株凋亡,其机理可能与下调bcl-2表达有关。  相似文献   

2.
目的评价腺病毒介导p53基因(Adp53)转染对人胃癌细胞的凋亡效应和放射增敏作用。方法以重组腺病毒介导p53基因感染4种不同p53状况的人胃癌细胞,用免疫组织化学法和Western blot法检测P53蛋白在胃癌细胞中的表达;用细胞集落形成法检测细胞存活率;用TUNEL法检测细胞凋亡。胃癌细胞感染Adp53后照射4Gy,用流式细胞仪检测细胞周期分布和凋亡;胃癌细胞种植肿瘤内注射Adp53后照射6Gy,以肿瘤相对体积增长曲线观察肿瘤抑制情况。结果1:100效靶比(MOI)Adp53产生细胞高转染率,以及p53基因在4种胃癌细胞中均高表达,并产生G2/M期阻滞、凋亡增加和细胞增殖抑制。如果以凋亡评价放射效应,Adp53转染对4Gy照射4种细胞的凋亡率比值为:W细胞3.0,M细胞3.6,neo细胞2.2,823细胞2.5。体内实验结果显示,Adp53对w细胞肿瘤6Gy照射的抑瘤率比值为1.41,而对M细胞肿瘤为1.91。结论腺病毒介导p53基因转染产生细胞凋亡并提高人胃癌细胞的放射敏感性,这种作用不依赖于细胞内在的p53状况。  相似文献   

3.
目的 研究蒿甲醚(artemether)对人鼻咽癌CNE-1细胞放射敏感性的影响及其作用机理。方法 用MTT法检测蒿甲醚对CNE-1细胞生长的抑制效应;克隆形成法检测蒿甲醚对CNE-1细胞放射敏感性的影响;流式细胞仪检测不同处理因素对CNE-1细胞的细胞周期的影响;Western blot分析蒿甲醚对电离辐射诱导的CNE-1细胞中的细胞周期调控蛋白Cyclin B1和Wee1表达水平的影响。结果 蒿甲醚可抑制CNE-1细胞的增殖,且药物浓度和作用时间相关;20 μmol/L蒿甲醚对CNE-1细胞有放射增敏作用,其放射增敏作用随作用时间的延长而延长,作用24 h 后增敏作用最强,放射增敏比(SER)为1.481。流式细胞仪分析表明,单纯60Co γ射线照射后G2/M期细胞比例上升,而G0/G1期细胞比例下降;药物和射线联合作用后,与单纯照射组相比,G0/G1期细胞比例上升(t=4.59,P<0.05),G2/M期细胞比例下降(t=10.60,P<0.05)。蒿甲醚可降低照射后CNE-1细胞内Wee1蛋白表达水平,提高Cyclin B1蛋白表达水平。结论 低浓度蒿甲醚对CNE-1 细胞有放射增敏作用;蒿甲醚通过改变细胞周期调控蛋白Cyclin B1和 Wee1表达水平,诱导G2/M 期阻滞而发挥放射增敏作用。  相似文献   

4.
目的观察低浓度乙醇诱导与紫外线照射导致HepG2肝癌细胞损伤的分子路径。方法选用HepG2肝癌细胞株,分别给予低浓度乙醇诱导与紫外线照射处理,观察两种损伤因素作用后细胞周期分布的差异,细胞中p53蛋白和p21蛋白表达的改变,分析蛋白表达与细胞周期改变的关系。结果紫外线照射后细胞中p53、p21蛋白表达均明显增强,出现G0~G1/G2~M期阻滞;低浓度乙醇诱导后主要出现G2~M期阻滞与p21蛋白表达的增强,p53蛋白表达改变不明显;两种损伤因素均能导致细胞凋亡率的增加。结论低浓度乙醇诱导与紫外线照射通过激活细胞内不同的分子事件,导致细胞周期与细胞凋亡的改变。  相似文献   

5.
人脑创伤后神经元凋亡及调节机制的观察   总被引:14,自引:1,他引:14  
目的:观察人类急性脑创伤后迟发性神经元死亡现象,了解调节人类神经元凋亡的机制及相关基因表达变化,为临床治疗迟发性神经元死亡寻找新的方法。方法:收集急性脑创伤患者脑标本,采用光镜、电镜以及凋亡细胞原位末端标记法(TUNEL)观察创伤后神经元DNA损伤情况;用原位杂交、免疫组化法观察bcl-2、bax、p53、caspase-3 p20亚单位在mRNA与蛋白质水平表达变化。结果:人脑创伤后有细胞凋亡现象发生,24h左右最为明显。正常人脑组织中几乎没有bcl-2、p53 mRNA及蛋白以及活化的caspase-3存在。急性创伤后bcl-2、p53 mRNA及蛋白表达增加;caspase-3被激活。正常人脑组织持续性表达高水平bax mRNA及蛋白,创伤后bax mRNA及蛋白表达升高。结论:人脑创伤后有细胞凋亡现象发生。人脑创伤造成bcl-2、bax、p53 mRNA及蛋白表达增加;caspase-3酶活性增加。  相似文献   

6.
目的 探讨表没食子儿茶素没食子酸酯(EGCG)对人鼻咽癌CNE-1细胞辐射敏感性的影响及相关机制.方法 将细胞分为对照组、EGCG单独处理组、UVC或X射线单独照射组,EGCG联合UVC或X射线照射组.四甲基偶氮唑盐(MTT)比色法检测不同浓度EGCG处理24、48和72 h对CNE-1细胞生长的影响,以及EGCG联合紫外线(UVC)及X射线对CNE-1细胞生长的影响.克隆形成实验检测EGCG对CNE-1细胞的放射增敏作用.流式细胞术检测细胞周期变化.Annexin V-FITC法检测细胞凋亡.Western blot法检测相关蛋白表达水平.结果 EGCG可抑制CNE-1细胞的生长,并有剂量·效应关系(r=0.817)和处理时间-效应关系(r=0.364).EGCG在低剂量50μmol/L,预处理2h,可增加CNE-1细胞对UVC和X射线的辐射敏感性.相比于单独照射组,EGCG联合UVC照射组细胞的S期阻滞消失(t=18.68,P<0.05),sub-G1峰的比例则明显增高(t =6.67,P <0.05).而且,Annexin V-FITC检测结果揭示,EGCG联合UVC照射组的细胞中早期凋亡细胞比例显著增加(t=10.28,P <0.05).但与单独照射组细胞相比,EGCG联合X射线照射组细胞的S期及G2/M期阻滞更明显(t=7.11和6.99,P<O.05),无明显的sub-G1峰出现.EGCG联合UVC照射可使凋亡相关蛋白Bax表达增加(t=5.42,P <0.05),Caspase-3表达增加(t=4.14,P<0.05),Bcl-2的表达变化并不明显(t=1.85,P>0.05),而其联合X射线对于细胞周期相关蛋白Cdc2 p34表达的影响不大(t=1.04,P>0.05).结论 EGCG可抑制鼻咽癌CNE-1细胞的生长.EGCG与UVC联合损伤作用与促进细胞发生早期凋亡相关,涉及到凋亡相关蛋白Bax和Caspase-3;而EGCG和X射线的联合损伤作用可能与周期阻滞相关.  相似文献   

7.
鼻咽癌放射抗拒相关的信号通路   总被引:1,自引:1,他引:0       下载免费PDF全文
目的 研究具有不同放射抗拒性的人鼻咽癌细胞株CNE-2R与CNE-2的基因表达谱差异,筛选与鼻咽癌放射抗拒相关的基因信号通路.方法 验证已构建的鼻咽癌放射抗拒细胞株CNE-2R的放射抗拒性,选用Human-6v3.0全基因组表达谱微珠芯片,筛选这2种细胞的差异表达基因.对差异基因进行生物信息学分析,寻找与鼻咽癌放射抗拒...  相似文献   

8.
为了解反复高正加速度(+Gz)暴露后大鼠脑组织中bcl-2、bax、p53和白细胞介素-1β转化酶基因的表达变化,探讨细胞凋亡在反复高+Gz暴露所致脑损伤中的病理作用,用半定量逆转录聚合酶链反应方法检测反复高+Gz暴露后大鼠脑组织中bcl-2、bax、p53和ICE表达水平,并用原位末端脱氧核苷酸转移酶标记法检测脑组织中的凋亡细胞。结果bcl-2在+Gz重复暴露后6h和24h表达明显降低,而bax、p53和ICE在6h和24h表达明显升高,6h组和24h组在大脑皮质、海皮CA1区和纹状体可见部分神经元发生凋亡。表明反复高+Gz暴露可引起大鼠脑组织中bcl-2、bax、p53和ICE表达变化,细胞凋亡是反复高+Gz暴露致脑损伤的机制之一。  相似文献   

9.
为研究辅酶NADH对顺铂(DDP)诱导的肝细胞凋亡的抑制作用及其分子机制,采用透射和扫描电镜检测肝细胞超微结构改变,碘化丙啶染色流式细胞术检测细胞凋亡,RT-PCR检测p53和bcl-2基因表达变化,并用紫外分光光度法测定凋亡分子caspase-3和caspase-8活性水平的改变。结果显示,与DDP组比较,NADH/DDP组典型凋亡超微形态改变不明显,细胞凋亡明显下降,p53基因表达下降,bcl-2基因表达上升,caspase-3和caspase-8活性维持在低水平。提示NADH具有明显抑制DDP诱导肝细胞凋亡的作用。  相似文献   

10.
60Co γ射线对肝癌细胞株HepG2增殖和细胞周期的影响   总被引:1,自引:1,他引:0       下载免费PDF全文
目的观察^60Coγ射线对肝癌细胞株HepG2增殖、凋亡和细胞周期的影响,并探讨γ射线对细胞周期改变与p27^kip1蛋白表达和分布之间的关系。方法以不同剂量的γ射线照射培养的HepG2细胞,观察细胞形态和生长曲线变化,同时应用流式细胞计数仪观察细胞周期和凋亡的改变,并应用免疫荧光方法观察p27^dip1蛋白的表达和分布改变。结果^60Coγ射线照射细胞引起HepG2细胞株剂量依赖性的生长抑制和凋亡增加。^60Coγ射线可引起细胞G2/M期阻滞,同时p27^kip1表达明显抑制,并主要分布于细胞浆。结论^60Coγ射线所导致的肝癌细胞株HepG2细胞的G2/M阻滞可能与细胞内D27^kip1“pl的表达抑制和细胞浆的分布比例增加有关。  相似文献   

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Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.  相似文献   

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KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief,intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.,≥90%of VO2 peak).  相似文献   

13.
In response to the ENFSI and EDNAP groups’ call for new STR multiplexes for Europe, Promega® developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex® ESI 16 (European Standard Investigator 16) and the PowerPlex® ESI 17 Systems. The PowerPlex® ESI 16 System combines the 11 loci compatible with the UK National DNA Database®, contained within the AmpFlSTR® SGM Plus® PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR® SGM Plus® kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex® ESI 17 System amplifies the same loci as the PowerPlex® ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR® SGM Plus® kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex® ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5 pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54–86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors.  相似文献   

14.
Objective To evaluate the preliminaily clinical efficacy and retrievability of a retrievable hinged covered metallic stent in the treatment of the bronchial stump fistula (BSF). Methods Between April 2003 and March 2005, 8 patients with bronchial stump fistula after pneumonectomy or lobectomy were treated with two types (A and B) of retrievable hinged covered metallic stents. Type A stent was placed in 6 patients and type B in 2 under fluoroscopic guidance. The stent was removed with a retrieval set when BSF was healed or complications occurred. Results Stent placement in the bronchial tree was technically successful in all patients, without procedure-related complications. Immediate closure of the BSF was achieved in all patients after the procedure. Stents were removed from all patients but one. Removal of the stents was difficult in two patients due to tissue hyperplasia. Patients were followed up for 6 - 21 months. Placement of the stents remained stable in all patients except one due to severe cough. Permanent closure of BSF was achieved in 7 (87.5%) of 8 patients. Conclusion Use of a retrievable hinged covered expandable metallic stent is a simple, safe, and effective procedure for closure of the BSF. Retrieval of the stent seems to be feasible. (J Intervent Radiol, 2007, 16: 253-257)  相似文献   

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Zusammenfassung Bei der rechtsmedizinischen Identifizierung kann die Identität im strengen Sinn allenfalls bei lebenden Personen festgestellt werden; sonst läßt sich nur von Teilen auf das Ganze (vom Untersuchungsobjekt auf die Person) schließen, wobei die verschiedenen Merkmale des Untersuchungsobjektes entsprechend der Hdufigkeit ihres Vorkommens eine unterschiedliche Beweiskraft haben. Bei der Schädelidentifizierung mit Hilfe moderner photographischer oder elektronischer Superprojektionsverfahren ergeben sich unter Berücksichtigung der Weichteildicken so viele (fiktive) Vergleichspunkte, daß bei geeignetem Vergleichsmaterial (Photographien) Identität wegen der Vielzahl übereinstimmender Bezugspunkte in den meisten Fällen evident ist.  相似文献   

19.
This is a review of the role of imaging procedures for the assessment of abdominal and pelvic lymph nodes. The diagnosis of malignant lymphatic spread is rarely the sole purpose of imaging, because it is usually part of a general abdominal examination, most frequently with CT or US, or increasingly with MRI. These studies are often requested in order to obtain information about the situation to be encountered during surgery, or to alert the surgeon to irresectability or to unexpected metastases outside the initially planned area of exploration. In most surgically treated tumours the role of imaging for preoperative staging is limited, due either to its insufficient sensitivity or because the initial treatment is independent of the lymph node stage. Imaging is commonly used to verify treatment response to chemo- or radiotherapy and for follow-up.Correspondence to: S. Delorme  相似文献   

20.
目的:探索CT-SIM三维定位系统、体模固定技术和PET-CT融合影像导引定位技术在胸部肿瘤经皮穿刺活检中的应用价值。方法:对380例胸部肿瘤患者行改进的CT定位技术下的经皮穿刺活检术。根据肿瘤的大小、深度、毗邻关系、活动度以及患者的心肺功能状态,综合运用CT-SIM系统、体模固定技术和PET-CT融合影像导引技术,为患者进行穿刺前定位。统计穿刺定位时间长度、成功率、确诊率、并发症发生情况,并与210例采用传统铅栅定位下胸部肿瘤穿刺活检的相应资料进行比较。结果:采用改进的CT定位技术的380例患者穿刺定位精确,平均定位时间(9.5 min)较传统方法(16.8 min)缩短7.3 min,活检成功率和确诊率分别是98.7%和95.3%,高于传统定位方法的93.3%和83.3%,两者差异均具有统计学意义(P〈0.05)。穿刺并发症发生率相似,气胸发生率分别为2.8%和2.9%,咯血发生率分别为11%和12.8%。结论:根据患者状态及肿瘤特点,在CT-SIM系统快速精确定位技术的基础上,综合运用体模固定技术和PET-CT融合影像导引技术,能显著缩短经皮穿刺活检的定位时间,提高活检成功率。  相似文献   

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