Friedman M, Orraca-Tetteh R
Adv Exp Med Biol. 1978;105:131-54. doi: 10.1007/978-1-4684-3366-1_9.
Hair samples from seven sick Ghanaian children were analyzed for amino acids. Cystine was determined by a procedure of Friedman using tributylphosphine and 2-vinylpyridine to change residues of cystine (and cysteine, if present) to S-beta-(2-pyridylethyl)-L-cysteine (2-PEC). This acid-stable derivative is released by normal acid hydrolysis and is eluted as a well-resolved peak before lysine in conventional ion-exchange amino acid analysis. The average cystine content of six children suffering from kwashiorkor or marasmic kwashiorkor was found to be about 20% less than that of the one remaining child, whose protein nutrition was judged adequate. In view of conflicting evidence of the relation of hair cystine content and nutrition, we believe further definitive studies of this subject are urgent. No other substantial difference in amino acid composition was noted.
对七名患病加纳儿童的头发样本进行了氨基酸分析。胱氨酸通过弗里德曼的方法测定，使用三丁基膦和2-乙烯基吡啶将胱氨酸（以及半胱氨酸，如果存在）残基转化为S-β-(2-吡啶基乙基)-L-半胱氨酸（2-PEC）。这种酸稳定的衍生物通过常规酸水解释放，并在传统离子交换氨基酸分析中在赖氨酸之前作为一个分辨率良好的峰被洗脱。发现六名患有夸休可尔症或消瘦型夸休可尔症的儿童的平均胱氨酸含量比剩余一名蛋白质营养被判定充足的儿童的平均胱氨酸含量低约20%。鉴于关于头发胱氨酸含量与营养关系的证据相互矛盾，我们认为对此主题进行进一步的确定性研究迫在眉睫。未发现氨基酸组成有其他实质性差异。
