人β-神经生长因子前体基因重组真核表达载体的构建

目的构建人β-神经生长因子(β-NGF)前体基因重组真核表达载体,为其在真核细胞中表达并获得具有神经生长因子活性的蛋白及临床应用打下基础。方法利用基因重组技术,将质粒PUC18-β-NGF进行酶切获得β-NGF基因片段,将其插入真核表达载体pcDNA3.0;用PCR技术以及酶切和测序对插入片段进行分析和进一步鉴定。结果人β-神经生长因子前体基因成功的插入真核表达载体pcDNA3.0。结论人β-神经生长因子前体基因重组真核表达载体pcDNA3.0-β-NGF构建成功,为进一步开展NGF基因治疗神经系统疾病奠定了基础。     

人β-神经生长因子前体基因重组真核表达载体的构建

目的构建人β-神经生长因子（β-NGF）前体基因重组真核表达栽体，为其在真核细胞中表达并获得具有神经生长因子活性的蛋白及临床应用打下基础。方法利用基因重组技术，将质粒PUC18-β-NGF进行酶切获得β-NGF基因片段，将其插入真核表达栽体pcDNA3．0；用PCR技术以及酶切和测序对插入片段进行分析和进一步鉴定。结果人β-神经生长因子前体基因成功的插入真核表达载体pcDNA3．0。结论人β-神经生长因子前体基因重组真核表达载体pcDNA3．0-β-NGF构建成功，为进一步开展NGF基因治疗神经系统疾病奠定了基础。     

重组腺病毒载体pAdeasy-1/pAdtrack-CMV-GFP-β-NGF的构建和鉴定

目的构建携带绿色荧光蛋白(GFP)标记的小鼠β-NGF重组腺病毒载体。 方法利用RT-PCR法从小鼠颌下腺总mRNA中扩增β-NGF全长cDNA片断,定向克隆于腺病毒穿梭质粒pAdtrack-CMV(已标记绿色荧光蛋白)中;在细菌中与缺陷型腺病毒基因组pAdeasy-1进行同源重组,构建Adeasy- 1/pAdtrack-CMV-GFP-β-NGF载体,并进行酶切鉴定。 结果成功获得小鼠-NGF全长扩增片段;pAdTrack-CMV-β-NGF测序验证含有目的基因;双酶切鉴定成功构建重组pAdTrack-CMV-β-NGF质粒;限制性内切酶的酶切分析结果证明成功构建同源重组的Adeasy-1/pAdtrack-CMV-GFP-β-NGF载体。 结论本实验所用方法可高效、安全构建腺病毒载体pAdeasy- 1/pAdtrack-CMV-GFP-β-NGF。     

miR-221基因干扰慢病毒载体的构建及其有效靶序列的筛选与表达检测

目的 构建携带人miR-221 基因的miRNA 干扰慢病毒载体并寻找其有效靶序列,为胶质瘤的研究提供一种新的方法.方法 合成含干扰序列的双链DNA oligo 直接连入酶切后的RNA 干扰载体上.将产物转入细菌感受态细胞,对长出的克隆进行PCR 鉴定,阳性克隆即为目的 基因RNA 干扰慢病毒载体质粒.再将目的 基因与目的 载体分别进行双酶切,纯化酶切产物后进行定向连接,其产物转入细菌感受态细胞,再对PCR 鉴定阳性的克隆进行测序和分析比对,比对正确即为融合蛋白过表达质粒载体,然后将两种质粒共转染入293T 细胞,用western bolt 法检测其有效敲减靶序列.结果 重组质粒经测序鉴定证明各转录模板完整、正确插入到相应质粒中,共转染后发现编号为PscSI576 的靶点干扰效果最好.结论 本实验成功构建了人miR-221 基因的RNA 干扰慢病毒载体,并找到了有效的干扰靶序列.     

人β-神经生长因子前体基因的克隆及序列分析

目的 对人β-NGF前体基因的克隆及序列分析,为其在真核细胞中表达并获得具有神经生长因子活性的蛋白及临床应用打下基础。方法 从人血白细胞中提取基因组DNA,采用PCR技术,扩增出含前导肽及信号肽的β-NGF前体基因并与PUC18载体连接,经筛选得到重组质粒PUC18-β-NGF,经酶切及序列分析进行鉴定。结果 经序列测定与Genebank中已知序列(V01511)相比较,完全一致。结论 从人白细胞DNA中获得了人β-NGF前体基因,为神经生长因子的基因治疗提供了条件。     

人β-神经生长因子前体基因的克隆及序列分析

目的 对人β-NGF前体基因的克隆及序列分析，为其在真核细胞中表达并获得具有神经生长因子活性的蛋白及临床应用打下基础。方法 从人血白细胞中提取基因组DNA，采用PCR技术，扩增出含前导肽及信号肽的β-NGF前体基因并与PUC18载体连接，经筛选得到重组质粒PUC18-β-NGF，经酶切及序列分析进行鉴定。结果 经序列测定与Genebank中已知序列(V01511)相比较，完全一致。结论 从人白细胞DNA中获得了人β-NGF前体基因，为神经生长因子的基因治疗提供了条件。     

SNCA基因过表达慢病毒质粒构建及稳定转染293T细胞系

目的构建SNCA基因过表达慢病毒质粒,转染293T细胞,建立稳定转染细胞系。方法应用PCR技术扩增目的基因,并将扩增产物插入慢病毒载体质粒pGC-FU上,并对阳性克隆进行基因测序鉴定。pGC-FU-SNCA-GFP重组质粒包装293T细胞,转染24小时后,用荧光显微镜观察标签GFP绿色荧光蛋白的表达,并用West blotting法测定目的蛋白的表达。结果成功构建了pGC-FU-SNCA-GFP慢病毒过表达质粒,获得了稳定转染的293T细胞株。结论人SNCA基因过表达慢病毒载体成功,构建和稳定转染293T细胞系的建立,为进一步体外研究α-突触核蛋白的功能奠定了基础。     

新型慢病毒载体的构建及其在人骨髓间充质干细胞基因转导中的应用

背景：构建一个组成性表达某特定基因同时携带荧光报告基因和抗生素筛选基因的慢病毒载体目前未见报道。 目的：观察新型慢病毒载体pLVpuro/EF1α-PEDF-IRES-EGFP在人骨髓间充质干细胞基因转导中的表达。 方法：通过PCR在PEDF基因的两端加上attB位点,构建表达载体pLVpuro/EF1α-PEDF-IRES-EGFP,将表达载体与包装质粒(ViraPowerTM Lentiviral Packaging Mix)共转染293FT细胞。通过多次感染的方法将慢病毒载体导入人骨髓间充质干细胞,转导后第7天开始使用1~5 mg/L嘌呤霉素筛选5 d,得到表达PEDF和EGFP的人骨髓间充质干细胞,并进行Western、Elisa的鉴定分析。 结果与结论：经PCR和测序证实,慢病毒表达载体pLVpuro/EF1α-PEDF-IRES-EGFP构建成功;将其成功导入人骨髓间充质干细胞,经过筛选获得纯化的过表达PEDF基因的绿色荧光细胞群。     

人EGFL7基因短发夹结构RNA慢病毒载体的构建及鉴定

目的构建人类表皮生长因子域7（EGFL7）基因RNA干扰（RNAi）慢病毒载体。方法将靶向EGFL7基因的短发夹结构RNA（shRNA）表达序列连接到包含U6启动子及绿色荧光蛋白（GFP）报告基因的慢病毒载体pGCL-GFP中,获得重组质粒,命名为pGCL-GFP-vshEGFL7,经多聚酶链反应（PCR）和测序鉴定后,与慢病毒包装质粒pHelper 1.0及pHelper 2.0通过lipofectamine 2000共转染至包装细胞293T,包装产生病毒液,测定其滴度。结果PCR扩增和测序结果证实EGFL7shRNA核苷酸链序列插入正确,包装慢病毒产生病毒悬液的滴度为4.8×107TU/ml。结论成功构建人EGFL7基因shRNA慢病毒载体。     

可溶性血管内皮细胞生长因子受体1真核表达载体pEGFP-N1/sflt-1构建及在人脐静脉内皮细胞中的表达

背景：研究表明,可溶性血管内皮生长因子受体Flt-1(sflt-1)基因在多种组织中表达,但其在内皮细胞中的表达尚待证实。 目的：获取人sflt-1基因,构建sflt-1基因真核表达载体pEGFP-N1/sflt-1重组质粒,检测其在人脐静脉内皮细胞中的表达。 设计、时间及地点：细胞学体外观察,于2008-05/12在南昌大学第二附属医院分子中心完成。 材料：pEGFP-N1真核表达载体为南昌大学第二附属医院分子中心保存,人脐静脉内皮细胞株购至南京基凯生物技术公司。 方法：从含有目的基因的质粒克隆模板中,利用酶切的方法获得目的基因,将目的载体进行酶切,纯化酶切产物后进行定向连接,其产物转化细菌感受态细胞,PCR鉴定为阳性的克隆,证明目的基因已经定向连入目的载体。再对PCR鉴定阳性的克隆进行测序和分析比对,比对正确的即为构建成功的融合蛋白表达质粒载体。用脂质体法将pEGFP-N1/sflt-1重组质粒转染人脐静脉内皮细胞。 主要观察指标：①重组质粒的酶切鉴定结果。②重组质粒的测序鉴定结果。③荧光显微镜及蛋白免疫印迹检测sflt-1基因在人脐静脉内皮细胞中的表达。 结果：①对PCR鉴定阳性的克隆进行测序和分析比对,与sflt-1基因片段全长2 063 bp理论值相符,证实pEGFP-N1/sflt-1重组质粒构建成功。②重组质粒送至上海捷瑞生物技术公司进行通测,测序结果证实插入片段序列与理论值完全一致。③荧光显微镜下可见重组质粒转染人脐静脉内皮细胞发绿色荧光,蛋白免疫印迹检测表明sflt-1基因能在人脐静脉内皮细胞中表达。 结论：实验成功构建了携带人血管内皮生长因子受体Flt-1的重组pEGFP-N1/sflt-1真核表达质粒,并证实其在人脐静脉内皮细胞中的表达。     

Type 1 human poliovirus binds to human synaptosomes

Poliovirus is a neurotropic virus that selectively infects human motoneurons in vivo. The basis for the specificity of this infection is not fully understood. It has been suggested that this tropism occurs because motoneurons are the only neurons to express poliovirus receptors. We have examined this hypothesis by measuring the binding of 125I-labeled poliovirus type 1 to neural tissues. With this assay we have detected highly specific binding sites in human but not rodent neural tissue. Regional assays of binding in human central nervous system homogenates demonstrate that binding sites are not confined to motoneurons. Rather, they are widely distributed throughout the human neuraxis. Particularly in the forebrain, binding is more abundant in gray than white matter. For this reason, we performed tissue fractionation studies which indicate that poliovirus binding sites are enriched in synaptosomes, the subfraction of central nervous system gray matter tissue rich in synaptic endings. The preferential expression of poliovirus binding sites in synaptic endings may be an important factor in the motor tropism of this virus, inasmuch as the major category of neurons with synaptic endings outside the central nervous system are motoneurons; thus, particles of virus may preferentially bind to this cell type during poliovirus viremia.     

Symptomatic human neurocysticercosis

Abstract. Objective: To evaluate the relevance of exposure and host biological factors in the heterogeneity of the clinical, radiological and inflammatory picture of neurocysticercosis (NCC). Methods: 105 Mexican symptomatic NCC patients confirmed by imaging were studied before they received any specific treatment. The relationships studied were those between a) the patients characteristics (gender, age and level of exposure), b) the type of clinical picture and c) the radiological and inflammatory characteristics of the disease (number, aspect, localization of the parasites, and CSF leukocytecounts). Results: Results Seizures were the most frequent symptom and multiple subarachnoid cysticerci the most frequent localization. Symptomatology related to the developmental stage, number and localization of the parasites as well as the CSF leukocyte-counts. The total number of cysticercal lesions and of vesicular cysticerci increased with age,whereas the number of colloidal cysticerci decreased. CSF leukocyte-counts were higher in women than in men. Levels of exposure did not correlate with the clinical and radiological pictures. Conclusions: The variability found in the number, stage, localization and inflammation in the parasite lesions is strongly associated with the heterogeneity of NCC symptoms. The increased number of vesicular cysticerci and the decreased number of degenerating cysticerci with aging, as well as the prominence of inflammation in women suggest that immuno-endocrinological factors may play a role in susceptibility and pathogenesis. The data also show that with increasing age and exposure there is no increment in severity, a suggestion that there might be ways of regulating pathogenicity.     

Disseminated human neurocysticercosis

Summary This study was based on two cases of disseminated human neurocysticercosis from India. The material availabel was examined grossly, and by light microscopy, histochemistry, immunomorphology and electron microscopy. The results showed that the parasites commonly embolized to the anatomically discernable gray-white matter junction of the brain and were located in cavities, the walls of which were dilated vascular channels. The parasite-nutrition process was through endocytosis and microtrichal activity. To camouflage themselves from the host-defense mechanisms, the parasites apparently covered themselves with host-tissue-like material. Host reactivity to the parasite was heralded morphologically by the physical anchoring of the parasite by activated endothelial cells, loss of the host-tissue-like cover and an acute polymorphonuclear leucocytic response.     

Age-related reduction of human growth hormone-binding sites in the human brain

Previous studies have shown that alterations in various neuroendocrine functions occur with increasing age. We here report a study of growth hormone (GH)-binding sites in different areas of post-mortem human brains collected from individual males and females of different age. The results indicate that there exists a significant negative correlation between the density of GH-binding sites and increasing age. This phenomenom was observed in both sexes in brain areas such choroid plexus, hippocampus, hypothalamus, pituitary and putamen but not in e.g. thalamus, In all tissues (expect for choroid plexus), the GH binding was significantly higher in those originating from females than those from males. This discrepancy was found likely to be associated with the affinity of GH to lactogenic rather than to somatogenic sites as no pronounced sex difference in binding was observed in the presence of excessive amounts of human prolactin. Data also indicate that the putative GH receptors in the various brain regions differ with regard to binding constants and to the estimated molecular size of the hormone-binding units. The loss of GH receptors in brain of elderly people may have consequences in several physiological courses. The decrease in GH binding at hypothalamic and pituitary levels may be of importance for the mechanisms behind the release or secretion of the hormone.     

Identification of human, rat and mouse nocistatin in brain and human nocistatin in brain and human cerebrospinal fluid.

Nocistatin was recently isolated from bovine brain and shown to block hyperalgesia and allodynia induced by nociceptin and prostaglandin (PG) E2. The counterparts of human, rat and mouse are deduced from their precursor prepronociceptin to be 30, 35, and 41 residue peptide respectively. To identify these mature forms of nocistatin, three peptides were synthesized and a detection program for nocistatin was developed, using high pressure liquid chromatography (HPLC) along with specific radioimmunoassay (RIA). Nocistatin extracted from human, rat and mouse brain were subjected to HPLC and nocistatin-like immunoreactivity (NST-IR) was determined. All three species showed two NST-IR peaks, one of which coincided with that of the corresponding putative nocistatin. The same NST-IR was also detected in human cerebrospinal fluid (CSF).