Self-assembled biomimetic monolayers using phospholipid-containing disulfides

Several phospholipid-based disulfide molecules were synthesized and attached onto the gold-coated silicon wafer using the self-assembling method. The syntheses of these surface-modifying agents were conducted by introducing bromoethylphosphorate (PBr), phosphorylcholine (PC) or phosphorylethanolamine (PE) groups on the terminals of a dialkyl disulfide. After disulfides adsorption onto gold substrate surfaces, the composition, the film thickness, and the conformational order of self-assembled monolayer surfaces were explored and discussed in detail based on reflection-absorption infrared spectroscopy, contact angle measurement, Auger electron spectroscopy, X-ray photoelectron spectroscopy, and so on. The monolayer having the PBr end group could also be converted to a PC surface by treating with trimethylamine. The model functional surfaces of Au-SC11-PC, -PE, -PBr, -OH or corresponding mixed layers were used to mimic biomembrane surfaces. The monolayer having PC groups was found to reduce fibrinogen adsorption as evaluated from protein adsorption experiments using quartz crystal microbalance. It also showed relatively low platelet adherence compare to the glass, PBr and PE surfaces. The cell viability test also revealed that the PC surface displayed lower cytotoxicity than other surfaces.     

大鼠孤束核内NT-LI成分生后发育和衰老变化的光镜和电镜观察

用免疫细胞化学和电镜相结合技术,在光镜和电镜水平对生后4天、15天、30天、90天、300天和760天6组大鼠孤束核内神经降压肽样免疫反应(NT-LI)成分的生后发育和衰老变化进行了定量研究。光镜下孤束核内NT-LI胞体和终末主要分布于最后区平面,多见于背侧亚核、内侧亚核和连合核内。电镜下内侧亚核内可见NT-LI胞体、树突、轴突及终末。6组大鼠孤束核内NT-LI细胞均数和内侧亚核内NT-LI终末密度及其突触密度均以生后4天至15天间增长最快,NT-LI细胞数在生后15天达到最高,NT-LI终末及突触密度在生后90天达到最高。三者在生后300天时均明显减少。发育期内侧亚核内NT-LI终末构成的突触以Gray Ⅰ型为主,至老年期则变为Gray Ⅱ型占优势。发育期内侧亚核内以含清亮囊泡伴颗粒囊泡的NT-LI终末为主,老年期此类终末明显减少。只含清亮囊泡的NT-LI终末从生后至老年变化不明显。     

人体神经定量电流感觉检测系统的研制

电流感觉阈值测试是人体神经感觉功能的定量感觉测试方法的一种．它采用特定频率的正弦恒电流刺激人体神经末梢感受器，检测人体对电流刺激的最小感受量，用于定量评估神经功能。本文回顾了国际上电流感觉阈值测试技术的发展与现状，介绍了我们开发的人体神经定量电流感觉检测系统。该系统采用生理心理统计算法过滤人体主观感受的影响，具有双盲全自动测量功能，测量结果具有很好的重复性。     

三氧化二锑诱导急性早幼粒细胞白血病细胞凋亡的研究

目的 研究锑剂三氧化二锑（Sb2O3)对早幼粒细胞白血病细胞株NB4凋亡的诱导作用，以寻求早幼粒细胞白血病治疗的新方法。方法 采用细胞生长曲线，形态学及硝基四氮唑蓝（NBT）还原试验，判定NB4细胞的生长，分化及功能。采用细胞周期分析和DNA电泳研究细胞凋亡。结果 Sb2O3能诱导早幼粒白血病细胞凋亡，且具有时间，剂量依赖性。结论 Sb2O3能有效地诱导早幼粒白血病细胞凋亡，提示锑剂诱导细胞半亡的疗法，有望成为临床治疗早幼粒细胞白血病的新方法。     

天然免疫与获得性免疫的进化关系

免疫有天然免疫和获得性免疫两种类型,它们有不同的机制和起源.天然免疫可识别某些"非己”细胞或分子并加以清除;获得性免疫则对分子抗原表位进行识别,按抗原提呈细胞等有无协同信号(发育阶段/类型)而有所区别.两者有不同的生物学起源与意义;天然免疫源于防御入侵者的需求,获得性免疫则源于系统及个体自身发育中调节细胞发育的需求.两者嫁接性混合进化形成了复杂的可识别"自己/非己”的免疫系统,并留下了神奇的机制.     

重组人免疫缺陷病毒Ⅰ型逆转录酶的纯化及其动力学性质

目的纯化重组人免疫缺陷病毒Ⅰ型逆转录酶（ＨＩＶ－１ＲＴ），筛选新的ＨＩＶ－１ＲＴ抑制剂。方法在适宜的培养条件下诱导工程菌Ｅ．ｃｏｌｉＪＭ１０９（ＰＫＲＴ２）可高效表达重组人免疫缺陷病毒Ⅰ型（ＨＩＶ－１）逆转录酶（ＲＴ）。应用ＤＥＡＥ－纤维素和磷酸纤维素离子交换柱层析法从细菌裂解液中分离、纯化重组ＲＴ。结果１升细菌培养液可得到１．１ｍｇ产物。ＳＤＳ－聚丙烯酰胺凝胶电泳分析显示所纯化的重组ＲＴ为由两个分子量分别为６６ｋＤ和５１ｋＤ的亚基组成的杂二聚体。酶活性测定结果表明，经纯化的重组ＲＴ具有很高的逆转录酶活性（比活力为１．４×１０４ｕｍｇ）。结论本文通过对ＲＴ反应条件的研究，优化了ＲＴ反应系统，并测定了磷甲酸钠（ＰＦＡ）对重组ＲＴ的抑制效应，结果表明ＰＦＡ对重组ＲＴ的抑制反应动力学机制与天然ＲＴ相同，从而进一步说明用此法纯化的重组ＲＴ可直接用于抗ＨＩＶ药物的筛选与评价。     

以淋巴结转移为首发症状的Merkel细胞癌一例

患者女,76岁.因发现左腹股沟肿物2个月,于2007年9月来本院就诊.门诊B超检查:左腹股沟多个肿大淋巴结,不融合,考虑为淋巴瘤.门诊手术取左腹股沟淋巴结1枚.     

不同给药途径的腺苷预处理对大鼠缺血再灌注心肌的保护

Objective To evaluate the effect on myocardial protection of adenosine preconditioning in different route of administration through right jugular vein and left ventricle.Methods 48 SD rats were randomly divided into ischemia reperfusion group(blank control),ischemic preconditioning group(IP,positive control),adenosine venous infusion group,adenosine in ventricular group,normal saline(NS)venous infusion group(negative control I)and NS in ventricular group(negative control Ⅱ).The ischemia reperfusion rats model were established in vivo,and then changes of heart function,serum cardiac troponin T (cTnT),superoxide dismutase(SOD),malondialdehyde(MDA)and expression of nuclear factor KB(NF-kB) were observed.Results SOD in IP[(208.63±23.88)U/ml],adenosine venous infusion group [(178.27±11.56) U/ml]and adenosine in ventricular group[(191.31±28.14)U/ml]were significantly higher than that in the ischemia reperfusion group[(145.05±23.18)U/ml](P<0.05),cTnT,MDA and expression of NF-kB were lower than that in the ischemia reperfusion group (P<0.05).Heart function was significantly better than that in the ischemia reperfusion group(P<0.05);SOD in adenosine in ventricular group was significantly higher than that in adenosine venous infusion group(P<0.05).cTnT,MDA and expression of NF-kB were lower than that in adenosine venous infusion group (P<0.05).Conclusion Adenosine preconditioning may mimic protective effect of ischemic preconditioning. The effect on myocardial protection of adenosine in ventricular group was better than that of adenosine venous infusion group.     

How self-initiated memorized movements become automatic: a functional MRI study

We used functional magnetic resonance imaging (fMRI) and dual tasks to investigate the physiology of how movements become automatic. Normal subjects were asked to practice some self-initiated, self-paced, memorized sequential finger movements with different complexity until they could perform the tasks automatically. Automaticity was evaluated by having subjects perform a secondary task simultaneously with the sequential movements. Our secondary task was a letter-counting task where subjects were asked to identify the number of times a target letter from the letter sequences was seen. Only the performances that achieved high accuracy in both single and dual tasks were considered automatic. The fMRI results before and after automaticity was achieved were compared. Our data showed that for both conditions, sequential movements activated similar brain regions. No additional activity was observed in the automatic condition. There was less activity in bilateral cerebellum, presupplementary motor area, cingulate cortex, left caudate nucleus, premotor cortex, parietal cortex, and prefrontal cortex during the automatic stage. These findings suggest that most of the motor network participates in executing automatic movements and that it becomes more efficient as movements become more automatic. Our results do not provide evidence for any area to become more activated for automatic movements.     

华南、华北人群HLA-DQB1等位基因多态性

目的从基因水平调查了中国华南、华北地区人群HLA-DQB1等位基因频率，并研究比较两地区人群HLA-DQB1多态性分布。方法采用深圳益生堂生物企业有限公司研制开发的“HLA-DQB1低分辨率分型基因芯片检测试剂盒”，应用聚合酶链反应．序列特异性引物＋序列特异性寡核苷酸探针芯片检测技术，对700名南方地区的中国人和320名北方地区的中国人进行基因分型。结果鉴定了10个HLA-DQB1等位基因，获得了一组准确、科学的统计数据。结论得到了中国华南、华北地区人群HLA-DQB1等位基因频率差异的数据，证明中国人群HLA-DQB1＊02，05，0601，0602，0603的分布南北差异有统计学意义（P〈0．05），为疾病相关性研究、人文科学研究提供了可靠的遗传学数据。