Cooperation between MEF2 and PPARgamma in human intestinal beta,beta-carotene 15,15'-monooxygenase gene expression.

Background: Vitamin A and its derivatives, the retinoids, are essential for normal embryonic development and maintenance of cell differentiation. beta, beta-carotene 15,15'-monooxygenase 1 (BCMO1) catalyzes the central cleavage of beta-carotene to all-trans retinal and is the key enzyme in the intestinal metabolism of carotenes to vitamin A. However, human and various rodent species show markedly different efficiencies in intestinal BCMO1-mediated carotene to retinoid conversion.

Reference values for second trimester fetal and neonatal organ weights and measurements.

To establish accurate reference ranges for the entire second trimester, we documented organ weights, body weight, and linear measurements for 597 fetuses and neonates with gestational ages ranging from 12 to 26 wk. We determined the mean and standard deviation for weights and measurements at each week of gestation using the StatView trade mark SE + Graphics statistical program. The analyses revealed a linear correlation between the gestational age and, respectively, the toe-heel length, crown-rump length, and crown-heel length.

Reference values for transverse cerebellar diameter throughout gestation.

The transverse cerebellar diameter (TCD) is well established in the ultrasound literature as a reliable parameter for estimating the duration of gestation. In cases of growth restriction the cerebellum is usually spared, making TCD a reliable indicator of gestational age even when other parameters fall off the appropriate growth curve. The purpose of this study is to establish normal values for the transverse diameter of the cerebellum in pathology specimens, and to determine if these values correlate with those obtained by ultrasound.