EVALUATION OF TECHNIQUES FOR THE ANALYSIS OF LIPOPROTEINS AND APOLIPOPROTEINS

血浆脂蛋白、脂蛋白和载脂蛋白的定量 是筛查表面健康的人所必需的， 高脂蛋白血症患者的随访我们研究了它的性能 两种直接测定低密度脂蛋白的新技术的比较 胆固醇(低密度脂蛋白-C)；可能是 人类。西格玛直接低密度脂蛋白胆固醇方法是基于去除高密度的 脂蛋白(HDL)和极低密度脂蛋白(VLDL) 被吸收者的免疫吸收和总胆固醇的测定 血清，而海伦娜直接胆固醇法涉及定量 用以下偶联酶反应评价胆固醇 琼脂糖脂蛋白组分的电泳法分离 凝胶。因此，海伦娜方法同时测量所有人的胆固醇。 主要脂蛋白组分，如高密度脂蛋白、脂蛋白(A)(Lp[a])、极低密度脂蛋白、低密度脂蛋白 还有乳糜棒。虽然两种直接胆固醇方法都能够 提供了分析上可接受的结果，揭示了一些局限性 两者都有。用西格玛方法测得的低密度脂蛋白胆固醇也含有微量 极低密度脂蛋白-C(作为其设计的一部分，Lp[a]-胆固醇的整体)， 而海伦娜方法在技术上对表演是敏感的。一位少校 这两种方法的优点是它们都可以在血脂症中进行。 标本和III型高脂蛋白血症患者(所谓 广义贝塔疾病)当使用Friedewald公式作为间接 对低密度脂蛋白胆固醇的估计是不恰当的。因为高甘油三酯血症不会 干扰这些新方法，也可以使用非禁食标本 用于诊断胆固醇紊乱和监测治疗 干预措施。

Quantification of plasma lipids, lipoproteins, and apolipoproteins often is required for screening of apparently healthy individuals and for follow-up of patients with dyslipoproteinemias. We studied the performance of two new techniques for direct measurement of low-density lipoprotein cholesterol (LDL-C); likely the most atherogenic cholesterol fraction in humans. The Sigma direct LDL-C method is based on removal of high-density lipoprotein (HDL) and very low-density lipoprotein (VLDL) by immunoabsorption and measurement of total cholesterol in the absorbed serum, whereas the Helena direct cholesterol method involves quantitative assessment of cholesterol by a coupled enzyme reaction following electrophoretic separation of various lipoprotein fractions in agarose gel. Thus, the Helena method concomitantly measures cholesterol in all major lipoprotein fractions such as HDL, lipoprotein(a) (Lp[a]), VLDL, LDL and chylomicrons. While both direct cholesterol methods were capable of providing analytically acceptable results, some limitations were revealed in both. LDL-C measured by the Sigma method also contained trace amounts of VLDL-C (and, as part of its design, Lp[a]-cholesterol in its entirety), whereas the Helena method was technically sensitive to perform. A major advantage of both methods is that they can be carried out in lipemic specimens and in patients with Type III hyperlipoproteinemia (so-called broad beta diseases) when use of the Friedewald formula as an indirect estimate of LDL-C is inappropriate. Since hypertriglyceridemia does not interfere with these new methods, non-fasting specimens can also be used for both diagnosing cholesterol disorders and monitoring therapeutic interventions.