人骨形成蛋白2真核表达载体的构建和体外表达

背景：骨形态发生蛋白2(bone morphogenetic protein 2,BMP-2) 是已知的所有生长因子中对骨的形成作用最强的生长因子，被认为是最具有前途的骨诱导物质。 目的：构建人骨形成蛋白2真核表达载体并观察其体外表达情况。 设计、时间及地点：自身对照实验，于2005-07/2006-05在华中科技大学同济医学院分子生物中心实验室完成。 材料：pcDNA3.1(+)载体由华中科技大学同济医学院左石博士惠赠；成骨肉瘤组织由华中科技大学同济医学院附属协和医院骨科提供。 方法：从人成骨肉瘤细胞中提取细胞总RNA，利用反转录-聚合酶链反应方法扩增获得人BMP-2基因cDNA，将基因片断重组到pGEM-T质粒中构建pGEM-T- hBMP-2重组质粒载体，转化到大肠杆菌DH5α后筛选阳性克隆，利用限制性酶切和DNA序列分析鉴定重组质粒。分别用RcoRI和NotI双酶切pGEM-T- hBMP-2质粒和pcDNA3.1真核表达载体，将克隆载体中人骨形成蛋白2基因重组到pcDNA3.1真核表达载体，提取质粒作酶切电泳、聚合酶链反应鉴定及DNA测序后，用脂质体体外转染小鼠骨髓基质细胞，反转录-聚合酶链反应检测BMP-2的表达。 主要观察指标：①人骨肉瘤细胞总RNA 反转录-聚合酶链反应结果。②重组质粒pGEM-T-hBMP-2 和pcDNA3.1-hBMP-2的构建和酶切鉴定。③BMP-2在小鼠骨髓基质细胞内的表达。 结果：人骨肉瘤细胞总RNA经反转录-聚合酶链反应扩增后，获得1.2 kb条带。经酶切电泳、聚合酶链反应鉴定及DNA测序证实实验成功克隆BMP-2基因，重组质粒pcDNA3.1- hBMP-2构建正确;该重组质粒能在体外培养的小鼠骨髓基质细胞中有效表达BMP-2。 结论：实验成功克隆人骨形成蛋白2基因并构建了此基因的真核表达载体。     

BDNF基因重组逆转录病毒表达载体pLEGFP-BDNF的构建与鉴定

目的构建脑源性神经营养因子(BDNF)基因重组逆转录病毒表达载体。方法根据 BDNF基因已知序列,设计合成一对引物并导入HindⅢ和BamH Ⅰ酶切位点;从大鼠海马组织提取总 RNA,逆转录聚合酶链反应(RT-PCR)获得编码BDNF的基因片段,与克隆载体pMD 18-T Simple连接构建pMDT-BDNF质粒;经HindⅢ、BamHⅠ双酶切,获得BDNF基因片断再克隆至逆转录病毒载体 pLEGFP-N1中构建重组质粒pLEGFP-BDNF。结果限制性内切酶酶切分析和PCR法鉴定表明为正确重组子,测序结果证实与已知序列吻合。结论构建的重组逆转录病毒表达载体 pLEGFP-BDNF含有序列正确的大鼠BDNF基因,可以作为今后治疗老年性痴呆动物模型转基因实验的基因来源。     

人重组pcDNA6.2/生长分化因子5质粒的构建及鉴定

背景：生长分化因子5是一种刺激肌腱、韧带塑型，增强愈合反应有效的生长因子，在活性组织工程肌腱构建中有重要作用。 目的：构建人重组pcDNA6.2/生长分化因子5质粒，为转染基质干细胞向肌腱诱导分化实验奠定基础。 设计、时间及地点：细胞基因工程体外实验，于2007-08/12在哈尔滨医科大学遗传学教研室和分子生物学教研室完成。 材料：根据Genbank（NM000557）中人生长分化因子5的序列化学合成一对引物,从人胎儿软骨组织提取总RNA。 方法：通过反转录-聚合酶链反应得到人生长分化因子5完整成熟肽基因。将所得基因片段插入克隆载体pcDNA6.2并转化入JM109菌株，提取重组质粒，PCR鉴定、酶切鉴定并测序。 主要观察指标：反转录-聚合酶链反应检测结果，PCR及SalⅠ和BamHⅠ双酶切鉴定结果,重组质粒测序与Genbank中序列比较结果。 结果：电泳显示，反转录-聚合酶链反应产物为一长约380 bp的带，阳性克隆质粒经PCR电泳及双酶切均出现约380 bp的片段。测序表明与Genbank中的序列完全相符。 结论：成功构建出人重组pcDNA6.2/生长分化因子5质粒，为组织工程化肌腱过程中种子细胞的制备提供转染质粒。     

心脏转录因子GATA结合蛋白4真核表达质粒的构建*☆

背景：有研究表明心脏转录因子GATA结合蛋白4(GATA4)与先天性心脏病的发生有密切的关系,但其机制不明,而目前尚未查及GATA4真核表达质粒构建类的报道。 目的：构建人类心脏特殊转录因子GATA4的真核表达质粒。 方法：对重组质粒pUC57-GATA4进行酶切获得GATA4基因编码区序列,将真核表达载体pCMV-Myc和GATA4基因在双酶切后用T4连接酶连接,构建重组质粒pCMV-Myc-GATA4,转化至大肠杆菌,提取质粒后经聚合酶链反应、双酶切及测序鉴定。 结果与结论：实验成功酶切重组质粒获得GATA4基因编码区约1.3 kb的目的片段,聚合酶链反应和酶切鉴定以及基因测序结果显示,构建的重组真核表达质粒中含有正确的GATA4基因序列,证实成功构建了含有GATA4基因的真核表达重组质粒。     

真核表达载体pIRES2-EGFP-PDLIM2的构建及在EJ细胞中的表达☆

背景：核因子κB在肿瘤生成过程中起重要作用,PDLIM2基因可以介导终止核因子κB的活性,解除核因子κB对肿瘤细胞的凋亡抑制作用。 目的：克隆人PDLIM2全长基因,构建pIRES2-EGFP-PDLIM2真核表达载体。 方法：采用反转录-聚合酶链反应从新鲜膀胱组织总RNA中克隆PDLIM2全长基因,与经Bam HI、Xho Ⅰ相同双酶切的pIRES2-EGFP质粒载体连接,构建重组质粒pIRES2-EGFP-PDLIM2,经酶切及测序鉴定重组质粒中PDLIM2基因的完整性和忠实性。荧光显微镜下观察重组质粒转染的EJ细胞GFP报告基因表达强度,并对转染细胞PDLIM2的表达进行RT-PCR检测。 结果与结论：经酶切和测序证实重组质粒构建正确,并在转染的EJ细胞中获得PDLIM2的高效表达。表明用反转录-聚合酶链反应方法成功从膀胱组织中克隆出PDLIM2全长基因,成功构建pIRES2-EGFP-PDLIM2真核表达载体。     

转化生长因子β1基因克隆及重组真核表达质粒的构建*★

背景：通过基因转移方法研究某一外源性基因在细胞中的作用是目前分子生物学常用的技术手段，与病毒载体相比，应用pcDNA4.0-TGF-β1真核表达质粒的转染方法无遗传毒性和细胞毒性，有更高的安全性。 目的：通过克隆转化生长因子β1基因，观察构建重组转化生长因子β1基因真核表达质粒的可行性。 设计、时间及地点：以细胞为观察对象的体外实验，于2007-03/2008-02在河南省高等学校临床医学重点学科开放实验室完成。 材料：2月龄清洁级健康SD大鼠，雌雄不拘，用于分离细胞中RNA。 方法：从大鼠骨髓细胞中分离提取转化生长因子β1的mRNA，反转录-聚合酶链反应扩增后，克隆入pGEM-T载体，PCR鉴定重组子；酶切下目的基因转化生长因子β1，再亚克隆入载体pcDNA4.0质粒，酶切鉴定亚克隆重组子并进行DNA序列分析。 主要观察指标：TGF-β1cDNA、pGEM-T-TGF-β1和重组子pcDNA4.0-TGF-β1的表达。 结果：经过反转录-聚合酶链反应扩增得到TGF-β1 cDNA条带；PCR扩增鉴定得到pGEM-T-TGF-β1。酶切鉴定得到亚克隆重组子pcDNA4.0-TGF-β1，经测序鉴定证实插入DNA序列与设计完全一致。 结论：成功克隆大鼠转化生长因子β1基因，并构建出重组转化生长因子β1真核表达载体。     

人端粒酶反转录酶和绿色荧光蛋白融合基因慢病毒表达载体的构建

外源性端粒酶反转录酶的表达可重建端粒酶活性,诱导细胞永生化。 目的：采用慢病毒载体作为基因转移载体,克隆人端粒酶反转录酶的编码区全序列,同时选用绿色荧光蛋白作为目的基因表达标志物,构建人端粒酶反转录酶慢病毒表达载体。 设计、时间及地点：开放性实验,单一样本观察,于2007-06/2008-03 在暨南大学生物工程研究所及暨南大学附属第一医院中心实验室完成。 材料：pBABE-puro-hTERT质粒由Robert Weinberg教授惠赠,质粒pDONR221,pLenti6/V5-DEST,ccdB Survival,Stbl3及293FT细胞由暨南大学生物工程研究所提供。 方法：以pBABE-puro-hTERT质粒为模板聚合酶链反应法获取目的基因人端粒酶反转录酶（包含酶切位点BglⅡ、HindⅢ）,通过BP反应克隆至pDONR221,以质粒pEGFP-N1为模板,以聚合酶链反应法获取目的基因增强型绿色荧光蛋白(包含酶切位点Hind Ⅲ,Bg Ⅲ),通过酶切及连接反应形成pDONR221-hTERT-EGFP。采用LR重组酶将pDONR221-hTERT-EGFP和pLenti6/V5-DEST进行重组反应,形成pLenti6/V5-DEST-hTERT-EGFP。将pLenti6/V5-DEST- hTERT-EGFP与包装质粒混合,利用脂质体共转染293FT细胞。 主要观察指标：通过酶切、聚合酶链式反应及测序验证重组质粒pDONR221-hTERT-EGFP和pLenti6/V5-DEST- hTERT-EGFP是否构建成功。包装重组慢病毒,应用荧光显微镜观察报告基因绿色荧光蛋白在293FT细胞中的表达情况。 结果：测序发现慢病毒入门载体pDONR221包含目的基因hTERT 1 547位点存在点突变(原碱基A变成G）,通过定点突变技术成功诱变并鉴定慢病毒表达载体pLenti6/V5-DEST-hTERT-EGFP成功构建。转染后的293FT细胞在荧光显微镜下观察可见强绿色荧光。 结论：实验成功构建了人端粒酶反转录酶和绿色荧光蛋白融合基因的慢病毒表达载体,为人端粒酶反转录酶稳定转染提供快速、简洁的方法。     

pcDNA3/BDNF真核表达载体的构建☆

背景：脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)作用广泛,但属于生物大分子,不能通过血脑屏障。基因治疗是目前解决脑源性神经营养因子给药途径最有希望的方案。 目的：拟构建大鼠脑源性神经营养因子基因真核表达载体。 方法：采用反转录聚合酶链式反应技术从SD大鼠脑组织提取总RNA,扩增脑源性神经营养因子基因cDNA序列,并将其克隆到真核表达载体pcDNA3中,分别取10 g质粒pcDNA3和纯化的目的基因分别进行EcoR Ⅰ、xho Ⅰ双酶切。将目的基因片段和pcDNA3载体连接,转入感受态DH5α细胞中,经酶切鉴定后送上海博亚生物技术有限公司测序。 结果与结论：RT-PCR产物为749 bp的特异片段,重组质粒pcDNA3/BDNF酶切后产生 749 bp和5 446 bp的片段,DNA测序证实749 bp片段的碱基序列与大鼠脑源性神经营养因子基因序列完全一致,成功构建了pcDNA3/BDNF重组质粒。     

人KiSS-1基因克隆及其慢病毒载体的构建**★

背景：慢性病毒载体技术是目前转基因中最有效和最成功的方法，技术操作简便。 目的：克隆转移抑制基因KiSS-1基因不含信号肽的表达序列，构建人KiSS-1基因的慢病毒表达载体。 设计、时间及地点：开放性实验于2006-09/2007-12在福建师范大学发育学院实验室完成。 材料：载体pNL-IRES2-EGFP由福建师范大学发育学院实验室保存。 方法：从人正常胎盘组织中提取总RNA，经反转录-聚合酶链反应得到KiSS-1基因开放阅读框cDNA序列，并将其克隆到慢病毒载体pNL-IRES2-EGFP中，构建其表达质粒pNL-IRES2-EGFP-KiSS-1。 主要观察指标：KiSS-1目的基因片段的克隆，重组表达质粒pNL-IRES2-EGFP-KiSS-1的酶切鉴定及测序。 结果：经酶切鉴定和基因序列测定，证实重组入载体pNL-IRES2-EGFP的片段为目的基因开放阅读框的核苷酸序列。 结论：成功构建了重组质粒pNL-IRES2-EGFP-KiSS-1。     

肿瘤血管抑制肽alphastatin基因克隆及序列分析

目的克隆获得编码具有生物学活性的肿瘤血管抑制肽alphastatin基因。方法采用非对称引物／模板法，依据基因库提供的alphastatin基因序列，设计合成alphastatin基因的引物／模板链，利用聚合酶链反应（PCR）法，从DNA中扩增出人肿瘤血管抑制肽alphastatin基因片段；将获得的基因片段插入质粒载体pGEM．TEasy中，转化到大肠杆菌DH5ct后挑选阳性克隆，利用限制性内切酶酶切鉴定重组质粒。结果经质粒DNA酶切分析及序列测定，获得了人肿瘤血管抑制肽alphastatin基因片段序列。结论首次体外克隆获得了人肿瘤血管抑制肽alphastatin基因，为肿瘤血管抑制肽alphastatin的基因治疗奠定了基础。     

Denervation study of synapses of organ of corti of old world monkeys

Fine structural characteristics of synapses in the spiral organ of Corti were examined, with reference to differences between inner and outer haircell systems, and to location of neurons of origin of efferent axons. Surgical interruption of crossed olivocochlear bundle, of vestibular nerve, of facial nerve, and excision of superior cervical ganglia were used to determine the pathways of efferent axons. Interruption of the vestibular nerve near the brainstem results in degeneration of all efferent terminals on outer hair cells. Mid-line lesions at, and caudal to, the facial colliculus result in degeneration of about half of these efferent terminals. Efferent synaptic bulbs to the inner hair-cell system are small, of the order of one micron, and form type 2 junctions with afferent dendrites. They tend to have more large dense-core vesicles (about 80 nm) than the large efferent terminals of the outer hair-cell system, and appear to be the terminals of axons in the habenula perforata, which exhibit varicosities laden with large dense core vesicles. The varicosities are unaffected by excision of the superior cervical ganglia. So far as our material can reveal, it appears that the varicosities in the habenula perforata do not survive vestibular root interruption, nor do the efferent processes in the internal spiral bundle or at the base of inner hair cells. Most interestingly, the afferent processes of the inner hair-cell system, as identified for example by their relation to pre-synaptic bodies in the inner hair cells, are subject to a trans-synaptic reaction after severance of the vestibular root. They undergo a dramatic cytological transformation, characterized by increase of volume, engorgement with microtubules, microfilaments, microvesicles of various sizes, and clusters of lysosomes. Thus, both the efferent and afferent terminals of the inner hair-cell system show marked cytological differences from the corresponding terminals of the outer hair cell system.     

Mechanism of action of tubocurarine on nicotinic cholinoreceptors of neurons of the sympathetic ganglia of rats

Tubocurarine (Tc) effect on membrane currents elicited by acetylcholine (ACh) was studied in isolated superior cervical ganglion neurons of rat using patch-clamp method in the whole-cell recording mode. The "use-dependent" block of ACh current by Tc was revealed in the experiments with ACh applications, indicating that Tc blocked the channels opened by ACh. Mean lifetime of Tc-open channel complex, tau, was found to be 9.8 +/- 0.5 s (n = 7) at -50 mV and 20-24 degrees C. tau exponentially increased with membrane hyperpolarization (e-fold change in tau corresponded to the membrane potential shift by 61 mV). Inhibition of the ACh-induced current by Tc (3-30 microM/1) was completely abolished by membrane depolarization to the level of 80-100 mV. Inhibition of ACh-induced current was augmented at increased ACh doses. It is concluded that the open channel block produced by Tc is likely to be the only mechanism for Tc action on nicotinic acetylcholine receptors in superior cervical ganglion neurons of rat.     

The effect of age of onset of PD on risk of dementia

Background Dementia occurs in the majority of patients with Parkinson’s disease (PD). Late onset of PD has been reported to be associated with a higher risk for dementia. However, age at onset (AAO) and age at baseline assessment are often correlated. The aim of this study was to explore whether AAO of PD symptoms is a risk factor for dementia independent of the general effect of age. Methods Two community-based studies of PD in New York (n = 281) and Rogaland county, Norway (n = 227) and two population-based groups of healthy elderly from New York (n = 180) and Odense, Denmark (n = 2414) were followed prospectively for 3–4 years and assessed for dementia according to DSM-IIIR. All PD and control cases underwent neurological examination and were followed with neurological and neuropsychological assessments. We used Cox proportional hazards regression based on three different time scales to explore the effect of AAO of PD on risk of dementia, adjusting for age at baseline and other demographic and clinical variables. Findings In both PD groups and in the pooled analyses, there was a significant effect of age at baseline assessment on the time to develop dementia, but there was no effect of AAO independent of age itself. Consistent with these results, there was no increased relative effect of age on the time to develop dementia in PD cases compared with controls. Interpretation This study shows that it is the general effect of age, rather than AAO that is associated with incident dementia in subjects with PD. Received in revised form: 22 December 2005     

Limits of deinstitutionalization--perspectives of relatives of psychiatric patients

After a hopeful beginning, the social process of the reintegration of those with severe mental illness has come to a standstill. I am led to wonder whether "the community" really wants to live together with people suffering from severe mental illness, and if so, how closely? As long as the medical treatment of mental illness provided by the general practitioners is fundamentally deficient, as they are not able to prescribe the necessary interventions--such as out-patient psychiatric nursing, and service providers in the out-patient sector are content with offering increasingly intensive forms of care for the less seriously ill at the cost of the Social Welfare System--the reintegration of those with serious mental illness remains an illusion--which is mainly to the benefit of providers of residential care in homes and hostels.     

Summary of Legislation of 1933 of interest to the Department of Mental Hygiene

Psychiatric Quarterly -