无线粒体DNA的人食管癌细胞系的建立

为了研究线粒体疾病呼吸键功能缺陷的分子遗传机制,我们用人食管癌细胞系制备无线粒体DNA的细胞系。在细胞培养液中加溴化乙院50ng／mL、尿嘧啶50μg／mL、丙酮酸100μg／nL,进行连续传代培养。Southern杂交及PCR结果均显示：线粒体DNA进行性减少,呼吸控制率渐降低,到溴化乙啶处理第12天时消失,细胞生长是营养缺陷型,成为无线粒体DNA的细胞系。     

人精子基因组DNA分离、纯化法的探讨与建立

哺乳动物,特别是人精细胞基因组DNA的分离、纯化极为困难,直至1988年Bahmak B.R.等提出了一个较好的分离、纯化法,但该法需用超速离心机进行梯度离心分离,还需要CsCl等贵重试剂,不适合我国国情,而在国内又未见到其它分离方法的报导。本文乃是经过反复地实验设计与摸索,建立了不用超速离心机的简而易行、适合我国国情的人精子基因组DNA分离、纯化法,经鉴定得到典型的大分子DNA电泳图象、符合质量标准。为今后我国有关工作及研究扫除了由于分离、纯化不到人精子基因组DNA而无法进行的困难。     

两种纯化噬菌体DNA方法的比较

两种纯化噬菌体ＤＮＡ方法的比较徐励新王凡＊刘彦仿（第四军医大学病理学教研室＊西京医院眼科，西安７１００３２）万大方顾健人（上海市肿瘤研究所癌基因与相关基因国家重点实验室，上海２０００３２）１材料和方法噬菌体λｇｔ１１贮存液以合适的滴度铺平板成单一噬斑...     

一步法快速制备培养细胞线粒体DNA

一步法快速制备培养细胞线粒体ＤＮＡ胡义德钱桂生陈维中黄桂君胡建林李淑平目前，制备真核细胞线粒体ＤＮＡ（ｍｔＤＮＡ）大致有两种方法：一是先提取细胞总ＤＮＡ，再通过氯化铯密度梯度离心或柱层析法分离纯化ｍｔＤＮＡ［１，２］；二是先将细胞充分匀浆，通过蔗糖不...     

人线粒体DNA荧光定量PCR检测方法的建立

建立SYBR Green I实时荧光PCR定量检测人线粒体DNA的方法。选取人线粒体DNA高度保守基因片段,将该基因片段与pCF-T载体连接后,转化入E.coli DH5α,提取重组质粒PCR及测序鉴定后,作为阳性模板建立SYBR-Green I荧光定量PCR标准曲线和熔解曲线。结果表明:构建的标准曲线线性关系良好(反应体系中含101~108拷贝时,扩增反应CT值与拷贝数的对数成线性关系),相关系数为0.997。批内和批间重复性测定的变异系数分别为1.23%~3.29%以及3.10%~5.21%。我们成功建立了实时荧光定量PCR检测人线粒体DNA的方法,该方法可作为进一步研究线粒体DNA的方法,在相关疾病诊断和监测中具有一定的应用前景。     

线粒体DNA提取方法的比较

目的将提取线粒体 DNA的碱变性法、Triton法、改进高盐沉淀法加以比较 ,以得到最方便快速提取线粒体 DNA的方法。方法分离 Wistar大鼠小肠上皮细胞 ,用 3种方法提取线粒体 DNA,紫外分光光度法定量。用琼脂糖凝胶电泳和线粒体 ATPase 8亚基基因 PCR扩增产物鉴定所提取的线粒体 DNA。结果改进高盐沉淀法线粒体 DNA量最多 ,Triton法最少。 OD2 6 0 / OD2 80均在 1.78～ 1.85间。将改进高盐沉淀法提取线粒体 DNA用于PCR扩增 ,测定出了线粒体 DNA ATPase 8亚基基因序列。结论改进高盐沉淀法提取线粒体 DNA具有操作简单 ,产量多的优点 ,该法所提取 mt DNA可用于 mt DNA测序     

几种线粒体DNA提取方法的比较

目的将提取线粒体DNA的碱变性法、Triton法、改进高盐沉淀法加以比较,以得到最方便快速提取线粒体DNA的方法.方法采用健康成年雄性Wistar大鼠,取回肠上皮细胞样本18份,每份含3×10?6细胞,每6份分别用碱变性法、Triton法、改进高盐沉淀法提取线粒体DNA,紫外分光光度法定量.再用琼脂糖凝胶电泳和线粒体ATPase6亚基基因PCR扩增产物鉴定所提取的线粒体DNA.结果3种方法提取线粒体DNA量差别明显改进高盐沉淀法量最多,为(1.26±0.23)μg;碱变性法次之,为(0.52±0.18)μg;Triton法为(0.31±0.16)μg.A260/A280均大于1.7.说明改进高盐沉淀法提取线粒体DNA具有操作简单,产量多的优点.将改进高盐沉淀法提取线粒体DNA用于PCR扩增,测定出了线粒体DNAATPase8亚基基因序列,说明该法所提取mtDNA可用于mtDNA测序.讨论和结论线粒体在细胞凋亡,衰老及程序化死亡中发挥重要作用.已在多种疾病中发现mtDNA突变.对线粒体疾病的分子遗传机理的研究可以进一步阐明这些疾病的病因,并为治疗提供理论指导.胡义德、Tamura和Palva等用碱变性法提取了人血白细胞、心肌等组织中mtDNA;戴纪刚等建立的Triton法先除去细胞核,再分离提取胞浆中mtDNA.而高盐沉淀法通过SDS(十二烷基硫酸钠)破坏细胞膜、核膜,使蛋白质变性,从而游离出核酸,EDTA抑制细胞中DNA酶的活性,蛋白酶K进一步将蛋白质降解成小肽,加入饱和乙酸钠后,绝大部分线性大分子量DNA和蛋白质在SDS作用下变性形成沉淀,环状mtDNA仍为自然状态,通过高速离心,即可得到mtDNA.3种方法各有优缺点碱变性法操作时间较短,要求条件比较严格,不易重复;Triton法通过核质分离提取mtDNA操作时间短,但产量低,易降解.而高盐沉淀法操作简单,易重复,产量多,可依需用量扩大反应体系,使mtDNA质量得以容易控制.     

氯化锂离心纯化质粒DNA方法的建立及其效果评价

本文建立了一种采用氯化锂离心纯化质粒ＤＮＡ的方法。该法不需要特殊的仪器设备和昂贵的试剂材料，操作简便易行。用此法对ｐＵＣ和ｐＧＥＭ等多种系统的质粒进行了提取纯化。结果表明：纯化的质粒ＤＮＡ无ＲＮＡ、蛋白质和染色质ＤＮＡ污染，其得率与氯化铯超离心法相近；酶切效果良好；可直接用于哺乳动物细胞的基因转移并获得有效表达。     

一例MELAS的线粒体DNA突变

为了检测中国ＭＥＬＡＳ患者的致病因素，采用Ｓｏｕｔｈｅｒｎ印迹杂交、ＰＣＲ、亚克隆及ＤＮＡ测序等技术，对１例中国线粒体脑肌病、乳酸中毒、中风样发作综合征（ｍｉｔｏｃｈｏｎｄｒｉａｌｅｎｃｅｐｈａｌｏｍｙｏｐａｔｈｙｗｉｔｈｌａｃｔｉｃａｃｉｄｏｓｉｓａｎｄｓｔｒｏｋｅ－ｌｉｋｅｅｐｉｓｏｄｅｓ，ＭＥＬＡＳ）患者的线粒体ＤＮＡ（ｍｔＤＮＡ）进行了突变分析。检测到ＭＥＬＡＳ患者特有的Ａ→Ｇ３２４３碱基替换，这一替换导致了一个新的ＡｐａⅠ酶切位点的形成。此突变型ｍｔＤＮＡ在检测的骨骼肌及血液标本中均被发现。突变型ｍｔＤＮＡ在检测的骨骼肌及血液ｍｔＤＮＡ标本中所占的比例分别为８０％和６０％。推测这一影响到ｍｔＤＮＡ中ｔＲＮＡｌｅｕ（ＵＵＲ）基因二氢尿嘧啶环的核苷酸突变是此例ＭＥＬＡＳ的重要致病因素。此外，在所测ｍｔＤＮＡ５６１ｂｐ（２９５０～３５１０）范围内还发现了１个Ｇ→ＴＮＤ１３４２３中性突变。     

A rapid and reliable method for PCR-based amplification of chromosomal and mitochondrial DNA from intact yeast cells

In this paper we describe a method to amplify mitochondrial and chromosomal DNA from yeasts by PCR using intact cells.     

人血细胞DNA无酚提取法

目的 寻找最佳的从血液尤其是凝血中提取DNA的方法,减少实验和临床检测血液的用量.方法 静脉抽取30份健康体检者的血样,分别抗凝、不抗凝处理后,用经优化的不需要酶和有机溶剂的抽提程序提取DNA,通过电泳和PCR进行检测.结果 凝血和抗凝血的DNA产量分别是(40.2±8.86)mg DNA/L和(39.1±10.2)mg DNA/L;纯度分别为1.87±0.11和1.92± 0.12.所有样本的DNA分子质量都很高,从两者的DNA样本中能很容易地扩增出t-PA基因的第8内含子区ALU等位基因二态性,因此所提取的DNA是完整可靠的.结论 该方法能快速、简单、有效、无毒地从新鲜血液和凝血中提取DNA,适合于临床检测和分子生物学研究.     

一种碘化钾提取外周血基因组DNA的方法

目的　建立外周血基因组DNA 的快速提取方法。方法　用碘化钾直接从外周血中提取基因组DNA。结果　用该方法提取的DNA 为大分子量DNA;A260/A280为1.85,A260/A230为2.2;提取效率大于90% ;DNA 体外扩增结果良好。结论　该方法简便、快速、经济,可用于大量临床标本的研究。     

A rapid and simple DNA fingerprinting method using RLFP and SSCP analysis of the hypervariable noncoding region of human mitochondrial DNA

A simple method for identification of individuals and maternity testing has been developed. This technique includes PCR amplification of the 199-bp hypervariable portion of the noncoding region of human mtDNA, digestion with RsaI and subsequent SSCP analysis of restriction fragments with DNA silver staining. Using this approach we have analysed the DNA fingerprint patterns of the family members. The fingerprints of maternally related individuals appeared to be identical in three generations, while maternally unrelated members of the family showed differences in their fingerprints, either in SSCP or both RFLP and SSCP patterns. Sequencing data have confirmed the results obtained. Further DNA fingerprinting analysis of 19 unrelated mother–child pairs by means of the method described revealed complete identity of the fingerprint patterns within the pairs. The probability of a random fingerprint match for two maternally unrelated individuals was estimated as 8%. © 1994 Wiley-Liss, Inc.     

A rapid and simple method for extracting yeast mitochondrial DNA

Summary A rapid method for the extraction of yeast mitochondrial DNA (mtDNA) is described. In comparison with previous methods, it simplifies several steps, does not require either the isolation of mitochondria or phenol treatment and is less time consuming. This protocol gives a high yield of pure mtDNA (50–120 g from a 100-ml culture), which can be directly used in various molecular applications: restriction enzyme digestion, electrophoresis, blotting, labeling, cloning and sequencing.     

孕妇外周血中无细胞胎儿DNA的研究进展及应用

孕妇外周血中无细胞胎儿DNA(cffDNA)是无创性产前诊断中重要的胎儿物质的检测来源.由于孕妇血中大部分是母体DNA,而游离胎儿DNA的量非常少,仅占3％～6％.因此从孕妇血中成功分离cffDNA,对后续的无创性产前诊断有着十分重要的意义.本文分别从孕妇外周血中cffDNA的发现来源,cffDNA的结构与稳定性,分离孕妇外周血中的cffDNA的实验方法,及在无创性产前诊断中的应用等方面进行介绍,并着重对该技术近年来的研究进展作一综述.旨在探寻较高效率分离孕妇外周血中cffDNA的实验方法,为无创性产前诊断提供较高浓度的检测物质,提高其准确率及成功率.     

Restriction enzyme analysis of mitochondrial DNA in aging human cells

Human diploid fibroblasts show a limited lifespan in vitro. To investigate the integrity of mitochondrial DNA (mtDNA) in aging fibroblasts, whole cell DNA samples from the human cell line IMR-90 have been prepared at 36, 22, and 3 population doublings (PD) from the end of the lifespan (63 PD). These DNA samples were then digested separately with 19 different restriction endonucleases, and the resulting fragments were separated by agarose gel electrophoresis and transferred to nitrocellulose filters. Fragment sizes were revealed by hybridization to 32P-labelled mouse mtDNA and autoradiography, and were compared with computer maps of fragments generated from the known sequence of human mtDNA. These 19 enzymes recognize a total of 297 recognition sites comprising 1315 nucleotide base pairs (bp), approximately 8% of the human mtDNA (16 569 bp). Control experiments reveal that a minor component representing as little as 5% of the total mtDNA can be detected. No changes were seen in the restriction fragment pattern with fibroblast cell age. It is concluded that there are no large deletions, insertions, or rearrangements in human mtDNA, and no single base changes in the detectable regions. This suggests efficient maintenance of mtDNA molecules and/or elimination of damaged mtDNA during fibroblast cell lifespan.     

人外周血树突状细胞对LAK细胞杀伤活性的影响

从人外周血中分离出树突状细胞，体外观察了其对ＬＡＫ细胞活性的影响。发现：５×１０２～１×１０４／ｍｌ树突状细胞对ＬＡＫ细胞活性起增强作用，而５×１０４～１×１０５／ｍｌ树突状细胞却抑制ＬＡＫ杀伤活性。这说明人外周血树突状细胞对ＬＡＫ细胞活性起双相性调节作用。     

Detection and quantitation of human papillomavirus DNA in peripheral blood mononuclear cells from blood donors

Human papillomavirus (HPV) is the etiological agent of cervical cancer. Also, HPV has been associated with anogenital cancer, oropharyngeal cancer, genital warts, and other dermatological diseases. HPV infects epithelial cells and their replication is closely linked to epithelial differentiation. The presence of HPV DNA in peripheral blood mononuclear cells (PBMC) has been reported in some patients with head and neck cancer, cervical cancer, and other genital diseases. However, the presence of HPV DNA in blood in asymptomatic subjects is still unresolved. The objective of this study was to evaluate the presence of HPV DNA in PBMC from asymptomatic blood donors. Blood samples were collected from 207 healthy Chilean blood donors. Genomic DNA was extracted from PBMC and HPV DNA detection was performed by real-time quantitative polymerase chain reaction assays with GP5+/6+ primers. HPV typing was carried out by genetic sequencing of a 140 to 150 bp fragment of the L1 gene. HPV DNA was detected in 6.8% (14/207) of blood donors. Single HPV infections were detected in seven blood donors. High-risk HPV was found in 6.3% (13/207) of cases: nine blood donors were infected with HPV-16, five with HPV-18, two with HPV-51, and one case was infected with either 32, 33, 45, 59, 66, 70, or 82. The median viral load value was 21.3 copies/mL blood or 13.4 HPV (+) cells per 10 ⁴ PBMC. These results show that HPV DNA is present in PBMC from healthy blood donors and it suggests that blood could be a new route of HPV dissemination.     

A rapid two-step procedure for the purification of human peripheral blood basophils to near homogeneity

Background Basophils are increasingly utilized as indicators of allergic inflammation and as primary allergic effector cells to study signalling pathways. However, until the present, their enrichment has been time consuming, costly and limited to relatively few specialized laboratories. Objective We have therefore devised a reproducible and rapid method for the purification of human basophils from small quantities of peripheral blood within 1.5 h, which does not require the use of specialized equipment such as elutriators. Methods Human basophils were obtained from healthy volunteers undergoing venipuncture. Heparinized or K3‐ethylenediaminetetraacetic acid blood samples were first subjected to centrifugation in Hetasep, directly followed by negative selection using immunomagnetic beads. Basophil morphology and purity were assessed by May–Grünwald staining of cytospins. IgE‐mediated histamine release was analysed spectrofluorometrically and IL‐4 and IL‐13 production by quantitative RT‐PCR. CD203c and CD63 surface expression was measured using flow cytometry before and after activation with anti‐IgE. Results Using this protocol, basophils were enriched close to homogeneity in most cases with a mean purity of 99.34±0.88% (range 97–100%, n=18) and a mean recovery of 75.6 (range 39–100%, n=8). Basophil viability following purification was 99.6±0.89% using Trypan blue exclusion. The purification procedure gave rise to basophils with normal functional responses to anti‐IgE regarding histamine release as well as IL‐4 and IL‐13 mRNA expression. Moreover, constitutive cell‐surface CD203c/CD63 expressions were not elevated before anti‐IgE stimulation. Conclusion The rapidity, simplicity and reproducibility of this method will facilitate the employment of basophils in high‐output ex vivo studies.