2型糖尿病肾病患者红细胞膜上钠-钾ATP酶活性的变化

为了解2型糖尿病肾病(diabetic nephropathy,DN)不同时期红细胞膜上Na+-K+-ATP酶活性变化,为临床诊断、治疗提供理论依据,按尿白蛋白排泄率(urinary albumin excretion rate,UAER)将已确诊为2型糖尿病的51例患者分为3组糖尿病正常白蛋白尿组(DM1组),微量白蛋白尿组(DM2组),大量白蛋白尿组(DM3组);20例健康人作为对照组,男性11例,女性9例,平均年龄58.27±10.89岁.将对照组及实验组抽血做红细胞膜Na+-K+-ATP酶活性检测.结果表明DN各组红细胞膜Na+-K+-ATP酶活性较对照组均显著降低(均为P=0.000).说明DN患者红细胞膜Na+-K+-ATP酶活性下降,控制血糖、维持Na+-K+-ATP酶活性对改善DN预后有十分重要的意义.     

The identification of chemical intermediates in enzyme catalysis by the rapid quench-flow technique

Traditionally, enzyme transient kinetics have been studied by the stopped-flow and rapid quench-flow (QF) methods. Whereas stopped-flow is the more convenient, it suffers from two weaknesses: optically silent systems cannot be studied, and when there is a signal it cannot always be assigned to a particular step in the reaction pathway. QF is a chemical sampling method; reaction mixtures are aged for a few milliseconds or longer, ‘stopped’ by a quenching agent and the product or the intermediate is measured by a specific analytical method. Here we show that by exploiting the array of current analytical methods and different quenching agents, the QF method is a key technique for identifying, and for characterising kinetically, intermediates in enzyme reaction pathways and for determining the order by which bonds are formed or cleaved by enzymes acting on polymer substrates such as DNA. Received 24 May 2006; received after revision: 3 July 2006; accepted 19 July 2006     

Bcl-6对滤泡辅助性T细胞的调控作用及机制进展

Bcl-6是滤泡辅助性T细胞(Tfh)的亚群决定转录因子，在Tfh细胞分化和功能调节过程中发挥关键作用.Bcl-6调控Tfh细胞的分子机制及其受到的精密分子调控受到广泛研究，近年来已取得了一定的进展.该文回顾了Bcl-6被鉴定为Tfh细胞亚群转录决定因子的研究历程，总结Bcl-6在Tfh细胞中的功能，综述Tfh细胞调控Bcl-6表达机制的研究进展，并对Bcl-6研究中的潜在问题和未来研究方向进行了展望.