逆转录病毒载体介导的外源性主要组织相容性抗原复合体基因转移及其在T细胞的表达

目的 建立一个在胸腺内表达外源性主要组织相容性抗原复合体(MHC)抗原的实验模型,为下一步研究作准备。方法 应用逆转录病毒载体介导的基因转移技术,首次将外源性MHC基因转移到T淋巴表达并应用聚合酶链反应(PCR)及反转录聚合酶链反应(RT-PCR)检测转染T细胞DNA及mRNA。结果 外源性MHC基因已整合到靶细胞染色体DNA并有效地转录;单克隆抗体免疫荧光染色流式细胞仪检测显示在转染T细胞膜有外源性MHC分子表达;转染效率为46.2％。结论 外源性MHC基因可以转移到T细胞稳定表达,为今后的研究提供了经验。     

雌、孕激素对IL-6基因在子宫内膜表达的影响

为了进一步了解白介素－６（ＩＬ－６）在生殖过程中的作用，应用斑点杂交和原位杂交方法，研究ＩＬ－６在小鼠子宫内膜的基因表达和雌、孕激素对这种表达的影响。实验证明，正常动情前期子宫内膜间质细胞有ＩＬ－６ｃＲＮＡ基因表达，切除动物卵巢，即可消除这种表达。如给去卵巢动物２ｍｇ孕激素加１０ｎｇ雌激素或２０ｍｇ孕激素加１００ｎｇ雌激素，它们的光密度（ＩＯＤ）值分别可达到２．３和２．５。结果证明，子宫内膜间质细胞是产生细胞因子ＩＬ－６的主要细胞之一，并受卵巢激素的调控。     

Cellular distribution of the new growth factor Pleiotrophin (HB-GAM) mRNA in developing and adult rat tissues

Summary Pleiotrophin (PTN), also known as HBGAM, belongs to an emerging cytokine family unrelated to other growth factors. We report here the first comprehensive study using in situ hybridization on the cellular distribution of this new heparin-binding growth factor mRNA in rat tissues. PTN mRNA was developmentally expressed in many — but not all — neuroectodermal and mesodermal lineages, whilst no PTN mRNA was detected in endoderm, ectoderm and trophoblast. PTN mRNA was found in the nervous system throughout development, with a post-natal peak of expression. In the adult nervous system, significant expression persisted in hippocampal CA1 pyramidal neurons and in cortical neurons, but also in different non-neuronal cells types in various locations (olfactory nerve, cerebellar astrocytes, pituicytes, Schwann cells surrounding the neurons in sensory ganglia). PTN mRNA was also found during development in the mesenchyme of lung, gut, kidney and reproductive tract, in bone and cartilage progenitors, in dental pulp, in myoblasts, and in several other sites. Expression was differently regulated in each location, but usually faded around birth. In the adult, PTN mRNA was still present in the meninges, the iris, the Leydig cells of the testis and in the uterus. PTN mRNA was also strongly expressed in the basal layers of the tongue epithelium, which is the only epithelium and ectodermal derivative to express PTN mRNA, and this only after birth. PTN is known to be a growth factor for perinatal brain neurons and a mitogen for fibroblasts in vitro. Recently, trophic effects on epithelial cells and a role as a tumour growth factor have been reported. The mechanisms of regulation and the functions of PTN are however still uncertain. Its expression pattern during development suggests important roles in growth and differentiation. Moreover, the presence of PTN mRNA in several adult tissues and the up-regulation of PTN mRNA expression in the gravid uterus indicate that PTN also has physiological functions during adulthood.     

Galanin gene expression declines with adulthood in the cholinergic fields of the horizontal diagonal band of male rats

The neuropeptide galanin (GAL) influences leaming and memory processes, perhaps by inhibiting cholinergic function. We recently reported that, in the rat, the nucleus of the horizontal limb of the diagonal band (HDB) exhibits the highest level of GAL mRNA coexpression by basal forebrain (BF) cholinergic neurons and, in the HDB, virtually all GAL mRNA-expressing neurons correspond to the cholinergic cell type. Since GAL gene expression is induced across puberty in many brain regions, we used in situ hybridization histochemistry and quantitative autoradiography to assess GAL gene expression across the rostro-caudal extent of the HDB in prepubertal and adult male rats and to determine whether GAL gene expression is also regulated during maturation in this BF region. Our results show that the number of GAL mRNA-expressing cells per section is significantly reduced in the HDB with adulthood. Post-hoc analysis indicated that these age-associated differences in the number of GAL mRNA-expressing cells per section could be ascribed to the rostral and central subregions of the HDB. Age-related differences in the labeling intensity of GAL mRNA-expressing neurons were also detected in the rostral and central subregions of the HDB. No age-associated differences in GAL gene expression were found in the caudal HDB subregion. These results suggest that: (1) in contrast to other brain regions, GAL gene expression in the cholinergic BF may be negatively regulated by factors concomitant with puberty; and (2) the inhibition of cholinergic function by cosecreted GAL may be enhanced prior to puberty within cholinergic neurons of the rostral and central aspects of the HDB.     

白血病抑制因子反义寡核苷酸对髓母细胞体外生长的抑制作用

为进一步认识白血病抑制因子（LIF）对人髓母细胞瘤生长的生物学作用，我们使用LIF反义寡核苷酸，在髓母细胞内特异性阻断LIF基因表达并观察它对靶细胞的生物学效应。结果发现，被处理细胞的LIF表达降低至RT／PCR检出的阈值之下，抗LIF的免疫组织化学染色亦呈阴性，同时，这些细胞的生长速度明显减缓。相反，用与反义寡核苷酸互补的正义序列处理的细胞无论在基因表达／产生，还是在生长速度方面，均和正常培养细胞的细胞相似，本研究从而提示了一条以LIF为对象的髓母细胞瘤以及其它LIF生长依赖性肿瘤的基因和免疫治疗途径。     

根除幽门螺杆菌疗效与细胞色素氧化酶P450 2C19基因多态性的关系

目的 比较雷贝拉唑与奥美拉唑三联疗法根除幽门螺杆菌（Hp）的疗效与细胞色素氧化酶P4502 C19（CYP 2C19）基因多态性的关系。方法 采用随机、对照研究方法，将169例因消化不良症状接受常规胃镜检查确诊为慢性胃炎且Hp阳性的连续患者分人两组：雷贝拉唑三联疗法组（RAC组85例）和奥美拉唑三联疗法组（OAC组84例）。Hp诊断依靠组织病理学检查并参考快速尿素酶试验、血清Hp抗体检测结果。RAC组、OAC组均给予三联治疗：RAC组：雷贝拉唑10mg，OAC组：奥美拉唑20mg，两组均联用羟氨苄青霉素1000mg和克拉霉素500mg，全部药物每日2次，疗程7d。采用聚合酶链式反应结合限制性内切酶技术（PCR-RFLP），进行CYP 2C19基因型分析，治疗结束后第28天用^14C尿素呼气实验检测Hp根除疗效。结果 160例完成治疗方案，RAC组及OAC组的Hp根除率按PP分析及ITT分析均无统计学差异（P〉0．05）。根据CYP 2C19基因型分析，160例中，弱代谢型（PM）、中间代谢型（IM）及强代谢型（EM）的Hp根除率分别为95．5%（21／22）、85．9％（73／85）和67．9％（36／53）。PM型及IM型的Hp根除率均显著高于EM型（P〈0．05），而PM型与IM型间差异无统计学意义（P〉0．05）。RAC组中，各基因型的Hp根除率差异无统计学意义（P〉0．05）。OAC组中。IM型与EM型间（P〈0．01）及EM型与PM型间（P〈0．05）差异均有统计学意义。结论 雷贝拉唑与奥美拉唑两种三联疗法均能有效根除Hp。总疗效差异无统计学意义。雷贝拉唑三联疗法疗效较稳定，个体间差异小。PM型及IM型的Hp根除率均较EM型为高。     

大肠重复癌MMR、p53、Bax、PCNA表达及微卫星不稳定性研究

目的探讨微卫星不稳定性 (MSI)在大肠重复癌与单发癌中的变化规律 ,及MMR、p5 3、Bax、PCNA表达与MSI的关系。 方法采用免疫组化、PCR SSLP法对 38例大肠重复癌患者的 5 1处癌灶及 35例单发大肠癌分别进行MMR、p5 3、Bax、PCNA表达的检测和 5个微卫星位点MSI检测。结果重复癌组复制错误阳性率为 5 3% (2 7/ 5 1) ,单发癌组为 17% (6 / 35 ) ,差异有显著性意义 (χ2 =11 2 5 ,P <0 0 1)。重复癌组中 ,RER 与MMR表达缺失有密切的相关性 ;RER 与 p5 3表达呈负相关 ;RER 组PCNA标记指数显著低于RER-组 ;RER 与低分化、近端大肠癌密切相关。结论MSI在大肠重复癌的发生上起着重要作用 ,MSI可作为预测大肠重复癌发生的重要标志。     

肝细胞生长因子在左肾动脉狭窄大鼠心血管中的表达及干预研究

目的　观察左肾动脉狭窄肾性高血压大鼠模型心肌和血管中肝细胞生长因子 (HGF)的表达 ,并观察缬沙坦和螺内酯对其表达的影响。方法　选用 6周龄SD大鼠 2 4只 ,制备左肾动脉狭窄肾性高血压模型 ,分为 4组 ,分别为手术组、假手术组、缬沙坦组、螺内酯组。治疗组分别用缬沙坦 3 0mg/kg·d-1、螺内酯 2 0mg/kg·d-1溶于饮水灌胃 ,1次 /d ,连续治疗 17周。用逆转录 聚合酶链反应 (RT PCR)法检测大鼠心肌和血管HGFmRNA水平。结果　 17周后 ,缬沙坦组和螺内酯组的心肌HGFmRNA/ β actinmRNA(1.17± 0 .0 8/ 0 .85± 0 .0 8)高于手术组 (0 .5 7± 0 .0 7) (P <0 .0 1) ,但低于假手术组 (1.3 5± 0 .0 9) (P均 <0 .0 1)。两治疗组肠系膜动脉HGFmRNA水平高于手术组 (P <0 .0 1) ,但低于假手术组 (P均 <0 .0 1)。结论　缬沙坦和螺内酯均能使左肾动脉狭窄肾性高血压大鼠心肌和血管中的HGF升高 ,同时伴有心肌和血管重塑的改善 ,说明HGF在左肾动脉狭窄肾性高血压大鼠的靶器官保护中起着重要作用     

浅谈基因治疗的现状及其面临的困境

基因治疗将在未来的疾病治疗中扮演重要的角色，然而这一新颖的技术却面临着诸多问题，本文论述了基因治疗的发展现状及其所面临的技术难题。