Robbins Ch. 2 Flashcards
What are the 2 biochemical pathways involved in muscle hypertrophy?
PI3K/AKT and G-protein coupled
What are the transcription factors activated in muscle hypertrophy?
GATA4, nuclear factor of activated T cells (NFAT), and myocyte enhancer factor 2 (MEF2)
What is the most common metaplasia and when does it occur?
columnar to squamous; respiratory tract in response to chronic irritation
Deficiency in what vitamin induces squamous metaplasia in the respiratory epithelium?
Vitamin A (retinoic acid)
What type of metaplasia occurs in Barrett’s esophagus?
squamous to columnar
What is the first manifestation of almost all forms of injury to cells?
Cellular swelling
Ischemia caused by obstruction in a vessel may lead to what type of necrosis except for in the brain?
coagulative
A localized area of coagulative necrosis is called what?
an infarct
The presence of dead leukocytes called pus is found in what type of necrosis?
Liquefactive necrosis
Focal bacterial or fungal infections cause what type of necrosis?
liquefactive
hypoxic death of cells within the central nervous system often manifests as what type of necrosis?
liquefactive
Necrosis applied to a limp, generally the lower leg, that has lost its blood supply is what type of necrosis?
Gangrenous necrosis
A granuloma is characteristic of what type of necrosis?
caseous necrosis
Caseous necrosis is most often encountered with what?
Tuberculous infection
What type of necrosis occurs with acute pancreatitis?
Fat necrosis
What type of necrosis is usually seen in immune reactions involving blood vessels?
Fibrinoid necrosis
What are the Anti-apoptotic proteins of the BCL2 family?
BCL2, BCL-XL, and MCL1
How do the anti-apoptotic proteins work?
By keeping the mitochondrial outer membrane impermeable they prevent leakage of cytochrome c and other death inducing proteins into the cytosol
What are the pro-apoptotic proteins of the BCL2 family?
BAX and BAK
How do the pro-apoptotic proteins of the BCL2 family work?
they increase the permeability of the outer mitochondrial membrane allowing cytochrome c to leak into cytoplasm
What are the sensors of the BCL2 family?
BAD, BIM, BID, PUMA and NOXA. (BH3-only proteins)
What does cytochrome c bind to once released into the cytosol?
APAF-1 (apoptosis-activating factor 1)
During apoptosis, what proteins enter the cytoplasm to bind to and neutralize cytoplasmic proteins that function as physiologic inhibitors of apoptosis?
Smac/Diablo
What receptor family are the death receptors for the extrinsic apoptotic pathway?
TNF receptor family
What are the most common death receptors?
TNFR1 and Fas
After fas binds to fasL, the cytoplasmic portion of fas binds to what adaptor protein?
FADD
FADD activates what caspase after binding to Fas?
caspase 8 and in humans caspase 10
What protein can inhibit the extrinsic apoptotic pathway?
FLIP
how does FLIP work?
binds to pro-caspase 8 but cannot cleave and activate it because it lacks a protease domain
What are the executioner caspases?
3 and 6
DNA damage induced apoptosis involves what gene?
tumor-suppressor gene TP53
What proteins accumulates in cells when DNA is damaged?
p53
What receptor mediates necroptosis?
TNF
What unique kinases are involved in necroptosis?
RIP1 and RIP3
What is a useful marker for identifying cells in which autophagy is occuring?
Microtubule-associated protein light chain 3 (LC3)
Coal worker’s pneumoconiosis is an abnormal intracellular acculation of what?
Carbon dust
How is melanin formed?
when the enzyme tyrosinase catalyzes the oxidation of tyrosine to dyhydroxyphenylalanine in melanocytes.
What type of calcification occurs locally in dying tissues?
dystrophic calcification
what type of calcification occurs when caldium salts are deposited in otherwise normal tissues?
metastatic calcification
Activation of certain tumor suppressor genes, particularly those encoded by what gene, seem to be involved in controlling replicative senescence?
CDKN2A locus
What familial syndrome is associated with a defect in TP53 gene?
Li-Fraymeni syndrome
