Human intrahepatic biliary epithelial cell lineages: studies in vitro.

The human intrahepatic biliary epithelium is composed of a morphologically heterogeneous population of epithelial cells. During liver cirrhosis, new biliary ductular structures develop at the portal margins that express markers of immaturity such as CD56 and Bcl-2. These markers are also expressed transiently on immature biliary duct precursors during embryological development; thus their reappearance during cirrhosis suggests a recapitulation of ontogenesis during some liver conditions.

Early expression of thyroid hormone deiodinases and receptors in human fetal cerebral cortex.

Thyroid hormones are known to be important for optimal development of the human central nervous system. Classically, maternal thyroid hormones have not been thought to have a major role in defining central nervous system development. However, recent epidemiological evidence has indicated that subtle deficiencies in circulating maternal thyroid hormones in the first trimester of pregnancy are associated with adverse neurodevelopment.