Most sensitive cell to hypoxic injury are

This explanation comprises of most likely questions to be asked on cell injury CELL INJURY Hypoxia is the most common cause of cell injury. Neurons are the most sensitive cell to hypoxic injury in the brain. Coagulative necrosis is associated with "tombstone appearance". It is seen with ischemic injury to all tissues, except central nervous system. Best example of coexistence of hypertrophy and hyperplasia is uterus during pregnancy (gravid uterus). Most common metaplasia is squamous metaplasia in the lungs of smokers. CD 95 plays a role in apoptosis. Mitochondria plays a pivotal role on apoptosis. Marker for apoptosis (programmed cell death) is annexin V. Most important stimulatory gene for apoptosis is p53 gene and most important inhibitory gene for apoptosis is bel family (bcl-2) of genes. Key words associated with apoptosis: caspases, cytochrome C and embryogenesis. 'Chromatin condensation’ is the hallmark feature of apoptosis. "Step ladder pattern" on gel electrophoresis is a feature of apoptosis. Stepladder fever is seen in typhoid/enteric fever. Lipofuscin is also known by several other names like 'lipochrome’, 'wear and tear' pigment, pigment of aging and "indicator of free radical injury". It gets deposited mostly in heart and liver. The endogenous brown-black pigments include melanin (present in skin) and homogentisic acid (the black pigment in patients with alkaptonuria). Dystrophic calcification: normal serum calcium levels and in dead tissues (areas of necrosis). Metastatic calcification: increased serum calcium levels and in living tissues. “Lungs" are the commonest site for metastatic calcification. Other sites include stomach, pulmonary vein, systemic artery and kidneys. Psammoma bodies: meningioma, papillary thyroid carcinoma, prolactinoma, glucagonoma and serous cystadenoma of the ovary. Oncocytes are formed with modified mitochondria. Germ cells have the capacity for self renewal because of telomerase activation. Cancer cells have the phenomenon of 'telomerase reactivation'. Germ cells have the maximum telomerase activity amongst all the cells of the body Cell cannibalization required for self survival is called autophagy. Gandy Gamma body is seen in congestive splenomegaly. It contains hemosiderin and calcium. Necroptosis is a caspase independent process which resembles necrosis morphologically and apoptosis mechanistically as a form of programmed cell death. Pyroptosis is a programmed cell death is accompanied by the release of fever inducing cytokine IL-1. It also involves caspases 1 and 11. Commonest fixative used for light microscopic examination: 10% buffered neutral formalin. Commonest fixative used for electron microscopic examination: glutaraldehyde.