We have observed pigmented cytoplasmic granules, with the characteristic staining properties of lipofuscin ( @entity47464 , "wear-and-tear") pigment, in newborn @entity1 liver. The pigment is found at the periphery of the lobule in hepatocytes and some bile ductular cells. It is acid-fast, PAS-positive after diastase digestion, slightly argyophilic and sudanophilic, and markedly Schmorl's- and peroxidase positive in paraffin sections. Difficult to see in sections stained with @entity1710 and @entity1711 , the pigment can be detected in unstained sections. The granules also resemble lipofuscin found in adult tissues, in their ultra-structural and enzymatic properties. They are polymorphic, contain granular material of moderate and high electron opacity, and are delimited by a single membrane. Acid phosphatase and beta-glucuronidase activities are visualized in the newborn granules, identifying them as lysosomes. The granules also contain @entity920 and, to a much lesser extent, @entity68 . The accumulation of @entity6973 pigment in lysosomes in many tissues correlates well with aging, and this process has been interpreted as a reflection of cellular degeneration or wear-and-tear. However, the presence of lipofuscin granules as a constant component of neonatal liver suggests that they are not a measure of cellular senescence.

@entity6973 (aging) pigment granules of the newborn XXXX liver.

@entity1 :: ('9606', 'Species') :: ['human'] @entity1711 :: ('MESH:D004801', 'Chemical') :: ['eosin'] @entity6973 :: ('MESH:D008062', 'Chemical') :: ['lipofuscin'] @entity47464 :: ('MESH:D002566', 'Chemical') :: ['ceroid'] @entity920 :: ('MESH:D003300', 'Chemical') :: ['copper'] @entity1710 :: ('MESH:D006416', 'Chemical') :: ['hematoxylin'] @entity68 :: ('MESH:D007501', 'Chemical') :: ['iron']
@entity1 :: (9606,Species) :: ['human']
