神经干细胞移植治疗缺氧缺血性脑损伤的实验研究

目的 研究神经干细胞移植治疗缺氧缺血性脑损伤的可行性。方法 取孕龄为12－16天的母鼠，从胎脑中分离神经细胞，进行培养、鉴定。用出生7天的SD大鼠的新生鼠制作缺氧缺血性脑损伤的动物模型，7天后接受神经干细胞移植（移植组，n＝16只），同时设置对照组，只注射磷酸缓冲液（对照组，n=8只），8－10周后，作Y迷宫实验检测大鼠的学习能力和记忆能力。取脑组织作免疫组织化学检查。结果 从大鼠胎脑中成功培养出神经干细胞，培养条件下呈悬浮状态生长，形成神经球，绝大多数的细胞表达神经干细胞的标志物神经巢蛋白（nestin）。接爱神经干细胞移植组大鼠的学习能力、记忆能力和对照组相比，有明显提高，差异具有显著性（P＜0.05）。接受神经干细胞移植大鼠组织中可见存活的移植细胞，并和宿主脑组织融合在一起。结论 在体外培养条件下，可从胎脑组织中培养出神经干细胞，移植到缺氧缺血性脑损伤大鼠脑内后，细胞与宿主的脑组织融合在一起，动物的学习、记忆能力有改善。移植神经干细胞是治疗缺氧缺知性脑损伤的有效方法之一。     

Cholera Toxin B-Mediated Targeting of Lipid Vesicles Containing Ganglioside GM1 to Mucosal Epithelial Cells

Purpose. To determine whether the non-toxic pentameric B subunit of Cholera toxin (CTB) binding to ganglioside GM1 on both the lipid vesicles and epithelial cells may provide a means to target lipid vesicles to mucosal cells expressing surface GM1. Methods. Sonicated lipid vesicles containing ganglioside GM1 were prepared. Inter-vesicle cross-linking due to pentameric CTB binding to these GM1 vesicles was determined with a sub-micron particle analyzer. Association of CTB to GM1 vesicles was analyzed with continuous sucrose gradient centrifugation. CTB-mediated binding of GM1 vesicles to human mucosal epithelial cells (Caco-2 and HT-29), mucous membranes of mouse trachea, and nasal tissues were detected with fluorescent labeled vesicles. Results. An increase in lipid particle size due to binding of CTB to lipid vesicles and inter-vesicles cross-linking was detected. At a 30-to-1 mole ratio of membrane-bound GMl-to-CTB, optimum increase in GM1 vesicle aggregation, was detected. Under such conditions, all the added CTB molecules were associated with GM1 vesicles. Time course analysis showed that inter-vesicles cross linking by CTB was detectable within 10 min. and reached a maximum value at 60 min. CTB associated GM1-vesicles bind to mucosal epithelial cells HT-29 and Caco-2 with similar affinity [K_d = 7.8 × 10^–4 M lipid (Caco-2) and 7.6 × 10^–4 M lipid (HT-29)]. GM1 mediated binding specificity was demonstrated by blocking with anti-GMl antibody and the insignificant degree of CTB-associated GM1 vesicle binding to GM1 deficient C6 cells. Conclusions. The CTB-mediated GM1 binding to multiple membrane surfaces provides selective localization of GM1 vesicles to GM1 expressing mucosal cells and tissues. The strategy may be useful in localizing drugs and proteins to gut and respiratory tract mucosa.     

左顶叶黑色素瘤并视力受损一例

患者，女性，14岁，因视物模糊7d、头痛3d于2004年10月8日入院。查体：神志清，全身皮肤黏膜无黑色素瘤的斑痣。右眼视力50cm数指，左眼视为0.1，双眼底视神经萎缩，余颅神经检查未见异常。头颅CT及MRI：幕上下脑室系统轻度扩大。     

A mathematical model of volatile release in mouth from the dispersion of gelled emulsion particles.

This paper presents a mathematical model of in-mouth volatile release from gelled emulsion particles dispersed in a continuous aqueous phase. Data based on APCI MS-Breath analysis is presented to demonstrate the effect of particle size, oil content and oil-water partition coefficients. It is shown that in-mouth release of aroma from the dispersion of gelled emulsion particles follows a two-component kinetic equation with fast and slow components. Both the fast and slow rate constants depend on the particle size, oil content and oil water partition coefficient of the aroma. The relative amount of aroma contributing to the fast and slow components also depends on the size of the particles. In order to understand this unexpected behaviour, an analytical model was developed that considers the interplay between the mass transfer of flavour across the interface of the particles and that across the air-liquid interface. Analytical expressions for the two rate constants and the relative ratio of aroma contributing to the fast component have been derived. From this model, three regimes of in-mouth release of aroma from the dispersion of gelled emulsion particles were identified including, the emulsion regime, the transition regime and the gel particle regime. In the emulsion regime, changes in the size of gelled emulsion particles had negligible impact on the overall release. In the transition regime, the release was controlled by the interaction of flavour transfer from the particles with that across the air-water interface. In the gel particle regime, aroma release at long times was governed by the particles and that at short times was governed by the air-water interface, and the two processes were fully decoupled. A simple relationship was derived for the critical size above which the release of aroma from the dispersion of gelled emulsion particles is affected by the size of the particles.     

胰岛素样生长因子1对新生大鼠缺氧缺血性脑损伤保护机制的研究

目的　建立单侧缺氧缺血性脑损伤 (HIBD)动物模型 ,研究胰岛素样生长因子 1(IGF 1)对HIBD的影响和可能机制。　方法　选择健康 7日龄Wistar大鼠 12 0只 ,建立HIBD模型 ,随机分成假手术组、HIBD组、HIBD后 0 .2mg/kg人基因重组IGF 1干预组 (RH IGF 1组 )、0 .0 6 6mg/kg人基因重组IGF 1干预组 (SRH IGF 1组 )及盐水对照组 (对照组 )。各组按观察时段进一步分为 2 4、4 8、72h组 ,每组 8只。各组于规定时刻观测脑形态学改变、谷氨酸 (Glu)含量、凋亡细胞计数、Bcl 2蛋白表达。　结果　 (1)HIBD 4 8h组Glu(116 2 .2± 10 8.1)mg/kg ,较假手术组(75 0 .9± 5 3.4 )mg/kg明显升高 (P <0 .0 5 ) ;HIBD组凋亡细胞计数 [2 4h :(7.6± 1.9) % ,4 8h(12 .6±1.2 ) % ,72h :(13.8± 0 .9) % ],较假手术组 [2 4h(2 .0± 0 .2 ) % ,4 8h(2 .0± 0 .3) % ,72h(2 .0±0 .2 ) % ]明显增加 (P均 <0 .0 5 )。 (2 )与对照组相比 ,RH IGF 1组脑组织病变减轻 ;干预 4 8h组Glu[SRH IGF 1组 (781.4± 5 4 .2 )mg/kg ,RH IGF 1组 (74 0 .5± 4 6 .6 )mg/kg],较对照组 (112 6 .6± 4 8.0 )mg/kg明显降低 (P均 <0 .0 5 ) ;RH IGF 1组凋亡细胞计数 [2 4h :(3.6± 0 .9) % ,4 8h(8.2± 2 .2 ) % ,72h(9.4± 1.4 ) % ],较对     

无精子症和严重少精子症134例遗传学分析

目的：研究无精子症和严重少精子症患者染色体畸变及Y染色体(Yql1区)无精子症因子(azoospermic factor，AZF)缺失情况，建立Y染色体微缺失的临床筛查方法。方法：对134例患者(无精子症97例，严重少精子症37例)经染色体核型分析及AZF、区三个位点8对引物PCR扩增，检测染色体畸变和Y染色体微缺失率。结果：134例中染色体核型异常9例，占6．72％。AZF缺失18例，缺失率为13．43％。无精子症和严重少精子症AZF、缺失率分别为14．43％、10．81％。结论：染色体畸变和Y染色体微缺失是导致无精子症和严重少精子症的主要原因之一。无精子症缺失率高于严重少精子症患者。AZF区三个位点8对引物PCR扩增可作为Y染色体微缺失的临床筛查方法。     

环氧化酶-2基因启动子甲基化及表达与胃黏膜病变的关系

目的 探讨环氧化酶2(COX-2)基因启动子区甲基化水平和蛋白表达与胃黏膜病变的关系,并对其相关的影响因素进行研究.方法 以1201例患有不同胃黏膜病变的高危人群为研究对象,采用免疫组织化学方法榆测COX-2表达,用亚硫酸氢钠-变性高效液相色谱(DHPLC)对COX-2启动子甲基化率进行定量分析,采用13C尿素呼气实验(13C-UBT)对幽门螺旋杆菌(H priori)感染状况进行测定.结果 COX-2甲基化率中位数随胃黏膜病变的加重逐渐升高,在浅表性胃炎和慢性萎缩性胃炎(SG/CAG)、肠上皮化生(IM)及不确定性异型增生和异璎增生(Ind DYS/DYS)病变中分别为10.6%、11.8%、13.8%,各病变组之间差异有统计学意义(X2=8.312,P=0.016).分层分析显示,在H pylori感染阴性病例中,COX-2甲基化率仍随病变加重明显升高,在SG/CAG、IM、Ind DYS/DYS病变中其中位数分别为8.8%、10.6%、14.1%(X2=6.629,P=0.036).进一步分析发现,COX-2甲基化率随着COX-2表达强度的增强而降低,由COX-2弱阳性表达的13.3%降至强阳性表达的7.6%(X2=10.400,P=0.015).结论 COX-2启动子甲基化水平与胃黏膜病变程度及H pylori感染状况密切相关,并与COX-2表达强度呈负相关,说明COX-2启动子区异常甲基化可能在胃黏膜病变的演变过程中起重要作用.     

诺迪康对心脏活动的药理学作用

目的 :探讨诺迪康对心脏活动的药理学作用。方法 :运用 ms2 0 0 0多媒体生物信号处理系统 ,经 Straub法制备离体蛙心灌流标本并检测心脏活动 ,利用血流动力学方法检测家兔的心室活动等相关指标。结果 :2 0 9mg/L 诺迪康组的心肌收缩力增强 4 0 .38% (n =2 1,P <0 .0 0 1) ,4 18mg/L 诺迪康组的心肌收缩力增强 76 .4 4 % (n =17,P <0 .0 5 ) ,6 2 7mg/L 诺迪康组的心肌收缩力增强 10 4 .95 % (n =2 5 ,P <0 .0 1) ,对照组的心肌收缩力无明显变化 (n =2 5 ,P >0 .5 ) ;三个实验组及对照组对离体蛙心率均无作用 ,P >0 .0 5 ;家兔血流动力学方面 ,诺迪康组的 dp/dtmax增加了 2 1.0 8% (n =10 ,P <0 .0 5 ) ,其他各指标在对照组及诺迪康组均未见显著变化。结论 :诺迪康能增强心肌收缩力且有明显的剂量效应关系 ,可加速心肌的收缩速度但对心肌舒张无明显影响     

3,5-diBr-PADAP直接光度法测定血清锌

目的　建立一种不去除血清蛋白、简便灵敏的直接光度法测定血清锌。方法　以新的有机试剂2 -(3 ,5 二溴 -2 -吡啶偶氮 ) -5 -二乙氨基酚 (3 ,5 diBr -PADAP)为显色剂 ,在有表面活性剂存在的Tris-HC1介质中 ,手工分析法和自动分析法测定血清锌。结果　该法线性范围 0～ 80 μmol/L ,手工分析法和自动分析法平均回收率为 99 9%和 10 0 2 % ,批内变异系数 (CV)和批间变异系数分别为 0 0 18、 0 0 17和 0 0 2 8、0 0 2 6,与原子吸收分光光度法比较具有良好的相关性 ,线性回归方程和相关系数分别为Y =1 0 0 4X -0 12 6,r=0 9912和Y =1 0 0 6X -0 195 ,r =0 0 992 8。 89例健康人血清锌含量分别为 8 96～ 2 2 5 2 μmol/L和 8 63～2 2 43 μmol/L (x± 2s)。结论　用 3 ,5 diBr-PADAP直接光度法测定血清锌方法简便、灵敏可靠 ,适合临床应用。