2型糖尿病患者载脂蛋白E基因多态性的研究

目的：探讨中国人2型糖尿病患者载脂蛋白E（apoE)基因多态性及其与血脂和载脂蛋白水平的关系。方法：采用聚合酶链反应－限制性酶切片段长度多态性法，分别对74例2型糖尿病患者及191例血脂、血糖正常且无糖尿病史者的apoE基因型、空腹血脂及载脂蛋白AI、AⅡ、B100、CⅡ、CⅢ及E进行全面分析。结果：2型糖尿病患者的血清甘油三酯（TG）、总胆固醇（TC），低密度脂蛋白胆固醇（LDLC），非高密度脂蛋白胆固醇（nHDLC),载脂蛋白B100、CⅡ、CⅢ、E水平及TG／HDLC比值较对照组显著升高（P＜0．01）；血清高密度脂蛋白胆固醇（HDLC），apoE/apoCⅢ比值显著降低（P＜0．05）。2型糖尿病组与对照组apoE基因频率分布无显著性差异（P＞0．05）。携带ε2等位基因组血清TG／HDLC比值较E3／3基因型显著降低；而携带ε4等位基因组血清apoAⅡ水平较E3／3基因型及携带ε2等位基因组显著升高（P＜0．001）。结论：2型糖尿病患者apoE基因多态性与血TG／HDLC及apoAⅡ有一定关联。     

Acetylcholine produces stimulus-specific receptive field alterations in cat auditory cortex

Frequency receptive fields (RFs) were determined before and after pairing iontophorectic administration of acetylcholine (ACh) with a repeated single-frequency stimulus in the auditory cortex of barbiturate-anesthesized cats. In 58% of the cells, the paired ACh + tone treatment produced subsequent alterations of frequency RFs. In half of these cases, the RF modifications were highly specific to the frequency that had been paired with ACh. Atropine antagoized the frequency-effects of ACh, suggesting that they were mediated via muscarinic cholinergic receptors.     

血管紧张素转换酶基因多态性与冠心病关系的研究

目的：探讨血管紧张素转换酶（ACE）基因多态性与冠心病及冠状动脉病变支数的关系。方法：应用PCR扩增ACE基因的16内含子上的287bp插入／缺失片段，确定ACE基因型。在各组间进行基因型和等位基因频率的比较，采用多因素逐步logistic回归分析ACE的DD基因型及其他易患因素对冠心病的作用。用冠状动脉造影标准确诊冠心病。结果：（1）冠心病组ACE的DD基因型和D等位基因频率均高于对照组（x^2分别为16．04，16．08；P均＜0．01）。D等位基因与冠心病的关联性较高（隐性作用时OR＝2．15，P＜0．01，显性作用时OR＝2．84，P＜0．01）。（2）冠状动脉单支，双支，三支病变组之间，ACE基因型分布和D等位基因频率均一致（x^2分别为1．50，1．06，P均＞0．05）。（3）多因素逐步logistic回归分析，排除公认的冠心病危险因素后，ACE的DD基因型仍是冠心病的危险因素。结论：（1）ACE基因多态性与冠心病有相关性；（2）ACE基因型分布和D等位基因频率与冠状动脉病变支数无关；（3）ACE的DD基因型是冠心病的独立危险因素。     

SLE小鼠高IgG血症Fcgr2b基因序列分析

目的: 测定系统性红斑狼疮(SLE)小鼠模型-NZB/WF1双亲NZB,NZW小鼠 Fcgr2b基因启动子区核酸序列,明确Fcgr2b基因启动子区的突变性质.方法:扩增NZB,NZW小鼠Fcgr2b基因启动子DNA进行核酸序列分析.采用ELISA法测定、比较(NZB×NZW )F1×NZW回交小鼠Fcgr2b基因B/W型与W/W型组间血清总IgG 水平.结果:NZB小鼠Fcgr2b基因启动子区与正常鼠Balb/C相比存在2个部位碱基缺失,分别为13 bp及3 bp.NZW小鼠除有3个碱基置换外,与Balb/C鼠该基因启动子区序列相同.回交小鼠Fcgr2b基因B/W型组血清总 IgG水平明显高于W/W型组(P<0.0001).结论:NZB小鼠Fcgr2b基因启动子区存在碱基缺失,且该缺失突变可能与血清总IgG水平升高有关.     

儿茶酚-邻-甲基转移酶基因多态性与强迫症

目的：探索儿茶酚-邻-甲基转移酶(COMT)基因多态性同强迫症临床特征的关系。方法：采用聚合酶链反应扩增技术与限制性片段长度多态(PCR-RFLP)测定120例强迫症(OCD)患者和130例健康对照者的基因型；根据Yale-Brown强迫量表评分将强迫症划分亚型。结果：强迫症患者COMT基因型与等位基因分布与健康对照者之间无显著差异；强迫行为组与强迫思想组的COMT基因型分布存在差异；G／A基因型多见于强迫行为组。结论：COMT基因多态可能对强迫症的发病没有直接的作用，但G／A基因型可能对症状是否表现为强迫动作有一定的影响。     

IL-1B-31及IL-1RN基因多态性与胃癌易感性关系

目的：研究白细胞介素1B基因(IL-1B)启动子区域-31位点和白细胞介素1受体拮抗剂基因(IL-1RN)多态性在中国南方人群胃癌患者与健康对照中的分布，初步探讨其各基因型与胃癌的关联性。方法：收集285例胃癌患者与265例健康人群的外周血标本和流行病学调查资料，提取基因组DNA，IL-1RN基因型采用PCR方法直接确定。IL-1B基因采用PCR—RFLP方法分型。结果：IL-1RN基因有5种基因型，分别是1／1、1／2、1／3、1／4、2／2型，其频率在病例组中分别为81．9％、14．6％、7．0％、1．8％和1．1％。而在对照组中分别为81．6％、16．5％、0、0．8％和1．2％。各基因型在病例与对照组中分布没有显著性差异。IL-1B基因-31位点3种基因型C／C、C／T、T／T在胃癌病例组中频率分别为21．8％、48．6％和29．6％。而在对照组中分别为27．9％、48．8％和23．3％。与C／C型比较，携带T／T基因型者胃癌发生的危险性增加63．3％(OR=1．633，95％CI=1．014～2．628)。这一危险性在高年龄组、男性、饮酒、HP感染阳性、有癌症家族史的人中更为显著。结论：IL-1B基因启动子区域-31位点多态性可能与该人群胃癌易感性相关；未发现IL-1。RN基因多态性与胃癌易感性关联。     

雌激素及其受体对心血管系统保护作用实验研究进展

雌激素对心血管系统具有重要的保护作用。雌激素及其受体主要通过调节血管舒张功能、抑制血管平滑肌细胞增殖和迁移以及影响肾素 -血管紧张素等介导这一保护作用。但临床上雌激素替代治疗尚未得到肯定 ,需进一步研究     

Assessment of changes in regional cerebral blood flow in patients with major depression using the 99mTc-HMPAO single photon emission tomography method

Regional cerebral blood flow was investigated in 14 patients with major depression diagnosed according to the DSM-III-R criteria (six patients with single and eight patients with recurrent episodes) and in ten healthy volunteers. The mean ages of the patients and the controls were 33.5 ± 2.7 and 31.6 ± 2.6 years, respectively. The severity of the depression was assessed using the 17-item Hamilton Depression Scale (mean: 23.2 ± 1.5). None of the patients was under medication. After administration of 500 MBq technetium-99m hexamethylpropylene amine oxime, a single photon emission tomography study was performed and then transaxial, sagittal and coronal slices were obtained. For the semiquantitative analysis of the data, the ratios of the mean counts/pixel to the whole slice were calculated for 24 regions on three consecutive transaxial slices in the orbitomeatal plane. Additionally, left/right and frontal/occipital ratios were calculated. Both sides of the temporal region had a significantly decreased cerebral blood flow (CBF) when compared to the controls. The left/right ratio of the prefrontal region was also significantly lower in the patients than in the controls. The Hamilton score had a negative correlation with blood flow in the anterofrontal and left prefrontal regions. According to our results, regional CBF seems to be decreased in the left prefrontal and in both temporal regions in major depression. The severity of depression is correlated with the reduction in CBF in the regions of the anterofrontal and left prefrontal cortex.