Growth Velocity and Plasma Amino Acids in the Newborn
Growth Velocity and Plasma Amino Acids in the Newborn
复制标题
新生儿的生长速度和血浆氨基酸
DOI：
10.1203/00006450-198505000-00008
复制
发表时间：
1985
影响因子：
3.6
通讯作者：
B. Wharton
中科院分区：
文献类型：
--
作者：
P. Scott;H. Berger;B. Wharton
摘要：新生儿的血浆氨基酸水平经常作为遗传性代谢性疾病筛查的一部分进行测量，或者不太常见地作为营养评估的一部分。我们研究了影响低出生体重儿出生前3周测量水平的某些因素。与其他研究一样，血浆氨基酸浓度随着胎龄和出生后年龄的增加而下降，并在一定程度上反映了饮食蛋白质的氨基酸组成。此外，还发现血浆支链氨基酸和胱氨酸与生长速度和氮保持呈负相关。这些结果可以被解读为一些低出生体重的婴儿营养不良。然而，伴随而来的人体测量和临床数据显示，这些特定的婴儿是健康的，生长迅速；他们不太可能真的营养不良。相反，我们认为它们正在经历“蛋白质经济”，这是由于它们的高增长率造成的，因此，它们将从增加饮食蛋白质中受益。在解释单个婴儿的血浆氨基酸值时，似乎必须考虑生长速度、成熟度和饮食。这对低出生体重儿的营养有两个影响。在接受脱矿乳清配方奶粉的婴儿中发现较高的血浆苏氨酸浓度，这确实促使人们在考虑进一步增加卵黄素比率时发出警告。在能量摄入量约为130千卡/公斤/天时，蛋白质可能在质量和数量上成为限制营养的因素。
ABSTRACT: Plasma amino acid levels in newborn babies are often measured as part of a screening for inherited metabolic disease, or less commonly as part of a nutritional assessment. We have examined certain factors which affect the levels as measured in low birth weight babies during the first 3 wk of life. As in other studies, plasma amino acid concentrations were shown to fall with increasing gestational and postnatal age, and to reflect to some extent the amino acid composition of the dietary protein. In addition, however, plasma branched-chain amino acids and cystine were found to be inversely related to growth velocity and nitrogen retention. These results could be interpreted to suggest that some low birth weight babies were malnourished. However accompanying anthropometric and clinical data showed that these particular babies were healthy and growing rapidly; they were unlikely to be truly malnourished. Rather we suggest they were experiencing “protein economy” resulting from their high growth rate, and would, therefore, have benefited from increased dietary protein. It seems that growth velocity, as well as maturity and diet, must be considered when interpreting plasma amino acid values in an individual baby. There are two implications for the nutrition of the low birth weight baby. The higher plasma threonine concentrations found in the babies receiving the demineralized whey formula does prompt a word of caution when further increase in the wheyxasein ratio is contemplated. At energy intakes around 130 kcal/kg/day, protein may become a limiting nutrient both in terms of quality and quantity.