Kreis R, Hofmann L, Kuhlmann B, Boesch C, Bossi E, Hüppi P S
MR Spectroscopy and Methodology Unit, Department of Clinical Research, University Berne, Berne, Switzerland.
Magn Reson Med. 2002 Dec;48(6):949-58. doi: 10.1002/mrm.10304.
Biochemical maturation of the brain can be studied noninvasively by (1)H magnetic resonance spectroscopy (MRS) in human infants. Detailed time courses of cerebral tissue contents are known for the most abundant metabolites only, and whether or not premature birth affects biochemical maturation of the brain is disputed. Hence, the last trimester of gestation was observed in infants born prematurely, and their cerebral metabolite contents at birth and at expected term were compared with those of fullterm infants. Successful quantitative short-TE (1)H MRS was performed in three cerebral locations in 21 infants in 28 sessions (gestational age 32-43 weeks). The spectra were analyzed with linear combination model fitting, considerably extending the range of observable metabolites to include acetate, alanine, aspartate, cholines, creatines, gamma-aminobutyrate, glucose, glutamine, glutamate, glutathione, glycine, lactate, myo-inositol, macromolecular contributions, N-acetylaspartate, N-acetylaspartylglutamate, o-phosphoethanolamine, scyllo-inositol, taurine, and threonine. Significant effects of age and location were found for many metabolites, including the previously observed neuronal maturation reflected by an increase in N-acetylaspartate. Absolute brain metabolite content in premature infants at term was not considerably different from that in fullterm infants, indicating that prematurity did not affect biochemical brain maturation substantially in the studied population, which did not include infants of extremely low birthweight.
人类婴儿大脑的生化成熟过程可以通过氢磁共振波谱（MRS）进行无创研究。目前仅知晓最丰富代谢物的脑组织含量详细时间进程，且早产是否会影响大脑的生化成熟仍存在争议。因此，对早产婴儿的妊娠晚期进行了观察，并将其出生时和预期足月时的脑代谢物含量与足月婴儿进行比较。在28次检查中，对21名婴儿（胎龄32 - 43周）的三个脑区成功进行了定量短回波时间氢MRS检查。采用线性组合模型拟合对波谱进行分析，大大扩展了可观测代谢物的范围，包括乙酸盐、丙氨酸、天冬氨酸、胆碱、肌酸、γ-氨基丁酸、葡萄糖、谷氨酰胺、谷氨酸、谷胱甘肽、甘氨酸、乳酸、肌醇、大分子成分、N-乙酰天门冬氨酸、N-乙酰天门冬氨酰谷氨酸、磷酸乙醇胺、异肌醇、牛磺酸和苏氨酸。发现年龄和脑区位置对许多代谢物有显著影响，包括之前观察到的由N-乙酰天门冬氨酸增加所反映的神经元成熟。足月时早产儿的脑代谢物绝对含量与足月婴儿相比没有显著差异，这表明在所研究的人群（不包括极低出生体重儿）中，早产并未对大脑的生化成熟产生实质性影响。
