PRENATAL DIAGNOSIS Ⅰ. EARLY DIAGNOSIS OF OPEN NEURAL TUBE DEFECTS BY QUALITATIVE ACETYLCHOLINESTERASE ISOENZYME IN AMNIOTIC FLUID

The measurement of amniotic fluid (AF) acetylcholinesterase isoenzyme (AChEI) is a relatively new method for early diagnosis of open neural tube defects (NTDs). As quantitative methods are of unproven reliability at present, the authors used a high resolving power qualitative method-vertical slab polyaerylamide gel electrophoresis. The benefits of this technique are: simplicity of operation, accuracy, unsophisticated equipment, and easily available reagents. Combined results of 9 NTDs studies revealed that samples from early pregnancy gave more accurate results than those from late pregnancy.     

蛋白激酶C在软脂酸诱导HepG2细胞胰岛素抵抗中的作用

目的从蛋白激酶C(PKC)信号通路角度,探讨游离脂肪酸(FFA)引起肝脏胰岛素抵抗(IR)的可能机制。方法培养HepG2细胞,同时设立对照组、软脂酸(PA)组、高胰岛素组。软脂酸组、高胰岛素组分别用250μmol/L PA、5×10-7mol/L胰岛素处理24h。然后对照组、软脂酸组再根据胰岛素刺激前加( )与不加(-)PKC抑制剂白屈菜红碱盐酸盐(chelerythrine chloride,CC)5μmol/L预处理1h,随机分为两亚组:对照组(-)、对照组( )、PA组(-)、PA组( )。葡萄糖氧化酶法测定胰岛素刺激后12h葡萄糖消耗量,蒽酮法测定胰岛素刺激后3h点细胞内糖原含量,Western blotting技术检测15min点细胞内P-Ser473PKB、P-Ser21/9GSK-3α/β水平。结果PA组(-)与高胰岛素组葡萄糖消耗量无统计学差异(P=0.523)。葡萄糖消耗量、细胞内糖原含量、P-Ser473PKB、P-Ser21GSK-3α、P-Ser9GSK-3β水平均显示,PA组(-)与对照组(-)比较显著降低(P值依次为0.000,0.000,0.004,0.004,0.028),对照组( )与对照组(-)比较略有升高但无显著性差异;PA组( )与PA组(-)比较显著升高(P值依次为0.000,0.014,0.043,0.041,0.035)。结论PA(250μmol/L)体外成功诱导了HepG2细胞产生IR,PKC信号通路在FFA引起肝脏IR中起着重要作用。     

慢性肝病蛋白C系统的变化及临床意义

目的：探讨血浆血栓调节蛋白（TM）、蛋白C（PC）和蛋白S（PS）与慢性肝病的关系。方法：用双抗体夹心ELISA法测定了136例慢性乙型肝炎和74例肝炎肝硬化患者血浆TM、PC和PS水平，并与35名正常者进行对照分析。结果：（1）慢性乙型肝炎及肝炎肝硬化患者血浆TM水平均显著增高。（2）慢性乙型肝炎及肝炎肝硬化患者血浆PC、PS水平均显著降低，并与病情严重程度呈显著负相关。结论：慢性乙型肝炎及肝炎肝硬化患者均存在肝窦内皮细胞损伤，且与凝血机制异常有关；检测血浆PC和PS可做为判断慢性肝病病情严重程度的指标。     

血浆蛋白C、蛋白S与脑梗死的相关性研究

目的研究血浆蛋白C、蛋白S与脑梗死发病的关系。方法对64例脑梗死患者及15例正常对照组进行血浆蛋白C(PC)、蛋白S(PS)检测,并分析其与脑梗死严重程度、年龄及其它脑梗死危险因素之间的关系。结果实验组血浆PC浓度(4.97±1.82μg/ml)与对照组血浆PC浓度(4.74±1.95μg/ml)之间差别无统计学意义;首发组血浆PC浓度(5.28±1.85μg/ml)与复发组血浆PC浓度(4.03±1.40μg/ml)之间差别有统计学意义(P=0.016);实验组血浆PS浓度(7.47±3.87μg/ml)与对照组血浆PS浓度(12.06±3.99μg/ml)之间差别有统计学意义,中老年组血浆PS浓度(6.58±3.33μg/ml)与青年组血浆PS浓度(9.28±4.33μg/ml)之间差别有统计学意义。结论PC降低是复发性脑梗死的危险因素之一;游离PS降低是脑梗死的危险因素;PS水平的降低导致PC功能的降低,进而凝血功能障碍,导致脑梗死的发生。     

Role of cytochrome P4502E1 in alcoholic liver disease pathogenesis

The intragastric tube feeding model is ideal for the study of the role of dietary factors and the effect of drugs on experimental alcoholic liver disease (ALD), since the model allows us to study the effect of a single variable in the diet on the pathology of liver where the blood alcohol level (BAL) is maintained over 150 mg%. By varying the dietary fatty acid composition we showed that the pathology was worsened by increasing linoleic acid or polyunsaturated fatty acids (PUFAs) in the diet where cytochrome P4502E1 (CYP2E1) was increased posttranslationally by high BAL. Concomitant with the increase in CYP2E1 there was evidence for an increase in lipid peroxidation (LP) by microsomes. Protein adducts of the products of LP were increased in the blood. Isoniazid (INH) enhanced this process and the pathology of ALD when INH was fed at therapeutic levels with ethanol. Preliminary studies show that diallyl sulfide, which inhibits and destroys liver CYP2E1 selectively, also modified the pathologic effects of ethanol. Thus we postulate that CYP2E1 induction plays a central role in the pathogenesis of ALD.     

Amadori糖化白蛋白对牛视网膜血管二酯酰甘油--蛋白激酶C级联的影响

目的 :探讨Amadori糖化血清白蛋白对牛视网膜血管二酯酰甘油 (DAG)———蛋白激酶C(PKC)信号级联的影响及d-α-生育酚的干预作用。方法 :体外制备的Amadori糖化的牛血清白蛋白 (AGSA)分别在生理浓度葡萄糖 (5 .5mmol/L)和高浓度葡萄糖 (2 0mmol/L)培养液中作用于新鲜牛视网膜血管。采用薄层层析和放射自显影法测定DAG含量和PKC活性 ;并检测d -α-生育酚预处理后DAG、PKC改变。结果 :在生理葡萄糖浓度下 ,牛视网膜血管暴露于AGSA2 4h或 72h后细胞内DAG含量、PKC活性均较对照组显著增加 ,当AGSA和高葡萄糖同时作用于牛视网膜血管时 ,DAG -PKC级联显著激活 ,分别为正常葡萄糖组的 3.4 7倍和 4 .5 4倍 ;在正常血清培养液中 ,与 5 .5mmol/L的葡萄糖相比 ,2 0mmol/L高糖在 2 4h时并不刺激DAG含量增加 (P >0 .0 5 ) ,而 72h时则较对照组增加 4 5 % ,PKC活性较对照增加 5 6 % ,而d -α -生育酚可逆转上述生化改变。结论 :Amadori糖化血清白蛋白可在生理葡萄糖浓度下刺激DAG -PKC途径活化 ,从而影响血管一系列生理功能 ,而d -α-生育酚对血管生化改变有保护作用。     

使用手性冠醚的高效毛细管电泳法研究伯胺类药物的手性分离

目的　采用HPCE法拆分伯胺类药物对映异构体。方法　缓冲液 2 0mmol/LTris 0 .1%H3 PO4(v/v)(pH 2 .0 6 ) +18 冠 6 四甲酸 (18C6H4) ;检测波长 2 10nm。结果　 8种伯胺类药物得以拆分。结论　缓冲液中添加手性冠醚的HPCE法能较好地拆分伯胺类药物。     

N-乙酰半胱氨酸对慢性阻塞性肺疾病患者血淋巴细胞DNA损伤的影响

目的　探讨N -乙酰半胱氨酸 (NAC)治疗不同病期慢性阻塞性肺疾病 (COPD)的疗效。方法　 49例稳定期、急性发作期COPD患者 ,随机分为观察组 (2 5例 )和对照组 (2 4例 ) ,观察组除给予常规治疗外 ,加用NAC(每次 2 0 0mg ,3/d ,连用 2个月 ) ;对照组仅给予常规治疗。治疗前后观察所有患者外周血淋巴细胞DNA损伤程度。结果　治疗前后比较 ,观察组稳定期、急性发作期DNA损伤明显降低 ,差异有显著性 (P <0 .0 5)。对照组稳定期DNA损伤程度亦有一定程度的改善 ,但差异无显著性 (P >0 .0 5) ,急性发作期DNA损伤程度降低 ,差异有显著性 (P <0 .0 5)。结论　COPD患者体内存在氧化 -抗氧化失衡 ,抗氧化治疗可降低COPD患者外周血淋巴细胞DNA损伤程度 ,急性发作期出现氧化应激。