Gladstone I M, Levine R L
Laboratory of Biochemistry, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892.
Pediatrics. 1994 May;93(5):764-8.
To develop a method capable of quantifying the oxidative modification of proteins in pulmonary fluid obtained during routine suctioning of neonates receiving ventilation, thus providing an integrated assessment of antioxidant defenses.
Consecutive sample of neonates receiving ventilation.
Neonatal intensive care unit.
Twenty-six neonates receiving ventilation with a gestational age of 24 to 42 weeks, from whom 246 samples were collected and analyzed.
The carbonyl content in the lavage samples was measured by reaction with 2,4-dinitrophenylhydrazine followed by high-pressure liquid chromatography. Oxidation of proteins caused introduction of carbonyl groups into the side chains of the protein, providing a convenient and relatively specific marker of oxidative damage. On the first day of life, the initial protein-bound carbonyl for each neonate was usually low and consequently was not significantly related to birth weight, gestational age, or initial ventilatory requirements. Examination of the changes in pulmonary protein carbonyl in the first days of life revealed correlations of interest. In the first day of life, four neonates whose average inspired oxygen were < 40% showed no increase in carbonyl content, whereas four neonates whose inspired oxygen was > 40% showed an average increase in carbonyl of 51% (P < .001). Also, the need for ventilation > 3 days was correlated with elevated carbonyl in those first 3 days. The carbonyl content averaged over the first 3 days was 0.13 +/- 0.02 mol carbonyl/mol protein for the eight neonates receiving ventilation < 72 hours, whereas the nine needing longer ventilation had a carbonyl content of 0.28 +/- 0.03 mol carbonyl/mol protein (P < .05). Seven neonates were treated with dexamethasone because of ventilator dependence at 14 days of age. In these neonates, treatment was associated with a 50% reduction in carbonyl content within 48 hours (P < .02).
Oxidative damage to pulmonary proteins can be quantitated in samples obtained during routine suctioning of neonates receiving ventilation. The amount of oxidatively modified protein may provide a quantitative assessment of oxygen toxicity and of pulmonary antioxidant defenses.
开发一种能够对接受通气的新生儿在常规吸痰过程中获得的肺液中蛋白质的氧化修饰进行定量的方法，从而对抗氧化防御进行综合评估。
对接受通气的新生儿进行连续采样。
新生儿重症监护病房。
26例接受通气的新生儿，胎龄为24至42周，共收集并分析了246份样本。
通过与2,4-二硝基苯肼反应，然后进行高压液相色谱法测量灌洗样本中的羰基含量。蛋白质的氧化导致羰基引入蛋白质侧链，这为氧化损伤提供了一种方便且相对特异的标志物。在出生第一天，每个新生儿初始的蛋白质结合羰基通常较低，因此与出生体重、胎龄或初始通气需求无显著相关性。对出生后最初几天肺蛋白羰基变化的检查揭示了一些有趣的相关性。在出生第一天，平均吸入氧<40%的4例新生儿羰基含量未增加，而吸入氧>40%的4例新生儿羰基平均增加51%（P<.001）。此外，通气>3天与最初3天羰基升高相关。接受通气<72小时的8例新生儿最初3天的羰基含量平均为0.13±0.02摩尔羰基/摩尔蛋白质，而需要更长通气时间的9例新生儿羰基含量为0.28±0.03摩尔羰基/摩尔蛋白质（P<.05）。7例新生儿因14日龄时呼吸机依赖而接受地塞米松治疗。在这些新生儿中，治疗与48小时内羰基含量降低50%相关（P<.02）。
对接受通气的新生儿在常规吸痰过程中获得的样本中肺蛋白的氧化损伤可以进行定量。氧化修饰蛋白的量可以提供对氧毒性和肺抗氧化防御的定量评估。
