噬菌体DNA的快速抽提

介绍一种噬菌体DNA的快速抽提方法.用聚乙二醇沉淀噬菌体颗粒,然后经DEAE纤维素纯化处理和酚抽提.与传统的噬菌体DNA纯化方法相比,改进后的方法方便、快速、经济,可获得高纯度的噬菌体DNA.     

一种新的以细胞表面受体为靶向的基因导入系统

鉴于胰岛素样生长因子Ⅰ号及Ⅱ号的受体 (IGFⅠR ,IGFⅡR)在人原发性肝癌中过量表达 ,以及表皮细胞生长因子受体 (EGFR)在多种人恶性肿瘤过量表达 ,设计和合成了针对IGFⅠR及IGFⅡR的 1 4肽E5和针对EGFR的 1 6肽GE7,以及流感病毒血凝素功能域 2 0肽HA2 0作为内吞小体释放寡肽 (Endosomereleasingoligopeptide,EOP) ,将它们分别与多聚阳离子多肽 (Polycationic polypeptide ,PCP)———多聚赖氨酸 (Polylysine ,PL)或鱼精蛋白 (Protamine,PA)共价连接 ,藉静电效应与DNA形成一个复合体 (E5 PCP/DNA/PCP HA2 0 ,GE7 PCP/DNA/PCP HA2 0 ) ,即构建的新的受体介导的靶向性非病毒型基因导入系统 .体内、外实验结果表明它们相对靶向且高效地将外源基因导入人恶性肿瘤细胞并得到预期表达     

内耳形态学和生理指标对缺铁性肾虚耳聋大鼠模型的评价作用

目的探讨耳蜗显微结构和生理指标对缺铁性肾虚耳聋大鼠模型的评价作用。方法选用体重30～32 g、无耳疾、听性脑干反应(auditory brainstem response,ABR)阈值正常的1～2周龄SPF级SD大鼠120只,雌雄分养,分为缺铁组80只、正常对照组40只,饲养时间12周;以出现肾虚证和至少一耳ABR阈值≥15 dB,作为判断肾虚耳聋的标准,获得缺铁性肾虚耳聋大鼠22只,从中选取肾虚耳聋大鼠20只,同时以20只正常大鼠作对照。观察耳蜗血管纹、螺旋器等耳蜗显微结构变化,检测ABR阈值以及血红蛋白和血清铁等指标的变化。结果实验组和正常对照大鼠的血红蛋白和血清铁分别为11.80 g/L,4.5μmol/L和45.9 g/L,22.23μmol/L,ABR阈值分别为(30±5)dB和(10±5)dB;实验组血管纹血管明显减少;螺旋器毛细胞听毛有缺失、倒伏现象。结论缺铁性肾虚耳聋大鼠血红蛋白、血清铁和ABR阈值,以及耳蜗血管纹、螺旋器等耳蜗显微结构变化等指标,均较为稳定,是较好的评价指标。     

Computational analysis and prediction for exons of PAC579 genomic sequence

To isolate the novel genes related to human hepatocellular carcinoma (HCC), we se-quenced P1-derived artificial chromosome PAC579 (D17S926 locus) mapped in the minimum LOH (loss of heterozygosity) deletion region of chromosome 17p13.3 in HCC. Four novel genes mapped in this genomic sequence area were isolated and cloned by wet-lab experiments, and the exons of these genes were located. 0-60 kb of this genomic sequence including the genes of interest was scanned with five different computational exon prediction programs as well as four splice site recognition programs. After analyzing and comparing the computationally predicted results with the wet-lab experiment results, some potential exons were predicted in the genomic sequence by using these programs.     

Computational analysis and prediction for exons of PAC579 genomic sequence

To isolate the novel genes related to human hepatocellular carcinoma (HCC), we sequenced P1-derived artificial chromosome PAC579 (D17S926 locus) mapped in the minimum LOH (loss of heterozygosity) deletion region of chromosome 17p13.3 in HCC. Four novel genes mapped in this genomic sequence area were isolated and cloned by wet-lab experiments, and the exons of these genes were located. 0–60 kb of this genomic sequence including the genes of interest was scanned with five different computational exon prediction programs as well as four splice site recognition programs. After analyzing and comparing the computationally predicted results with the wet-lab experiment results, some potential exons were predicted in the genomic sequence by using these programs.     

A novel receptor-targeted gene delivery system for cancer gene therapy

Some growth factor receptors, such as insulin like growth factor Ⅰ and Ⅱ receptor (IGF Ⅰ R, IGF Ⅱ R) and epidermal growth factor receptor (EGF R), have been proved to be over-expressed in a variety of human cancers derived from different tissue origins. Based on this molecular alteration, a polypeptide conjugate gene delivery system was designed and synthesized. It contains three essential moieties: a ligand oligopeptide (LOP) for receptor recognition, a polycationic polypeptide (PCP) such as protamine (PA) or poly-L-lysine (PL) as a backbone for DNA binding and an endosome-releasing oligopeptide (EROP) such as influenza baenagglutinin oligopeptide (HA20) for endosomolysis. These components are covalently conjugated as LOP-PCP-HA20 or in the form of a mixture of LOP-PCP and HA20-PCP. A 14 amino acid E5 was designed and synthesized as LOP for IGF Ⅰ R and IGF Ⅱ R, and a 16 amino acid GE7 as LOP for EGF R. Both E5 and GE7 systems could form stable complex with the plasmid DNA as E5-PCP/DNA/PCP-HA20 a     

马蹄荷化学成分研究

从马蹄荷(Exbucklandia populnea R.W.Br.)茎皮中首次分离得到6个化合物,通过波谱分析鉴定为β-谷甾醇(I)、胡萝卜甙(Ⅱ)、樱桃甙(Ⅲ)、芒花甙(Ⅳ)、圣草酚(V)和白藜芦醇(Ⅵ)。     

人类癌基因

<正> 细胞癌基因结构与功能的发现是近年来肿瘤研究的重大突破。目前,它已成为对癌变本质研究中的重要方面,引起广泛的重视。迄今为止,已有十余种人的癌基因从不同组织与胚层(结肠癌、肺癌、胰腺癌、胆囊癌、胱膀癌、纤维肉瘤、胚胎性横纹肌肉瘤等),不同来源(实体瘤、细胞株)的人体肿瘤细胞中检出。 癌基因(oncogene,或致癌基因、致肿瘤基因)是以原癌基因(proto-oncogene)的形     

基因修饰的肝细胞脾内移植后体内分布和基因表达的实验研究

为探讨基因修饰的肝细胞经脾内移植途径介导肝脏基因治疗的可行性和有效性,体外用NeoR基因或IL-2基因修饰小鼠正常胚胎肝细胞BNL CL.2,经脾内移植至正常同系小鼠体内(2×10⁶/只),观察NeoR和IL-2基因在不同脏器的表达.结果发现脾内移植NeoR基因修饰的肝细胞后24h,即可通过RT-PCR在肝脏中检测出NeoR基因mRNA的表达,持续表达11周以上;此外,NeoR基因在脾脏中短暂表达(24h至1周),在肺组织中也有一过性表达(48～96h).脾内移植IL-2基因修饰的肝细胞后,肝脏中可检测到稳定表达的IL-2mRNA(24h至11周),外周血中维持一定水平(5～40pg/mL)的IL-2,能增强肝脏Kupffer细胞Ia抗原的表达及脾细胞的NK杀伤活性.提示基因修饰的肝细胞脾内移植后能定向分布至肝脏,并同化入肝组织中长期存活,有效地表达外源基因,可成为肝脏靶向性基因治疗的可行途径.