Hepatic stellate cell A decreases progressively in liver injury. The activated stellate cell is also responsible for secreting collagen scar tissue, which can lead to cirrhosis. More recent studies have also shown that in vivo activation of hepatic stellate cells by agents causing liver fibrosis can eventually lead to senescence in these cells, marked by increased SA-beta-galactosidase staining, as well as p53 accumulation and activation of Rb–hallmarks of cellular senescence. Senescent hepatic stellate cells have been demonstrated to limit liver fibrosis by activating interactions with NK cells. The cells of Ito were named for Toshio Ito, a twentieth-century Japanese physician, who introduced a
Spermaceti organ Spermaceti organ The spermaceti organ is an organ that commonly appears in the heads of toothed whales of the family Physeteroidea, in particular the sperm whale. This organ contains a waxy liquid called spermaceti and is involved in the generation of sound. In the modern day Great Sperm Whale ("Physeter macrocephalus"), the spermaceti organ is far larger in proportion to the animal’s body than what would be explained by simple allometry, and the evolution of the organ has caused changes in basal skull morphology, which may implicate tradeoffs were made that compromised the functionality of other nearby features. The high