1. Growth Adaptations, Cellular Injury, and Cell Death Flashcards
List the permanent tissues (that can undergo hypertrophy but not hyperplasia).
1) Cardiac muscle
2) Skeletal muscle
3) Myocytes
What is the exception to the rule that pathologic hyperplasia can progress to dysplasia and cancer?
Benign Prostatic Hyperplasia (BPH) does NOT increase the risk for prostate cancer
How does a decrease in cell size occur?
ubiquitin-proteosome degradation of the cytoskeleton and autophagy of cellular components
True or false: metaplasia is irreversible.
FALSE (it is reversible with the removal of the driving stressor)
What is the exception to the rule that metaplasia can progress to dysplasia and cancer?
Apocrine metaplasia of the breast carries NO increased risk for cancer
What are the 2 major consequences of Vitamin A deficiency?
- Night blindness
- Maturation of immune system gets dysregulated
True or false: dysplasia is reversible.
TRUE (with alleviation of the inciting stress)
What cell type is most susceptible to ischemic injury (can survive only 3-5 minutes with no oxygen)?
Neurons
How does the response to quickly occurring ischemia differ from the response to slowly occurring ischemia?
Quickly occurring ischemia often leads to injury while slowly occurring ischemia often leads to growth adaptations
What are the 2 most common causes of Budd Chiari syndrome?
- Polycythemia vera
- Lupus anticoagulant
What is the characteristic PaO2 and SaO2 with anemia?
PaO2 and SaO2 are both normal
What is the characteristic PaO2 and SaO2 of CO poisoning?
PaO2 is normal and SaO2 is decreased
What is the characteristic PaO2 and SaO2 with methemoglobinemia?
PaO2 is normal and SaO2 is decreased
What is the underlying problem in methemoglobinemia?
oxidant stress (drugs) or immature machinery (newborns) leads to oxidation of the heme in iron which decreases oxygen binding capacity
How do you treat methemoglobinemia?
IV methylene blue
What is the hallmark of reversible cell injury?
cellular swelling (Na+/K+ ATPase can’t work so Na+ and water build up in cell)
What is the hallmark of irreversible cell injury?
membrane damage
Where is the ETC located?
inner mitochondrial membrane
What is the word for nuclear condensation?
pyknosis
What is the word for nuclear fragmentation?
karyorrhexis
What is the word for nuclear dissolution?
karyolysis
What ALWAYS follows necrosis?
inflammation
What is the pattern of necrosis where the tissue remains firm and the cell shape and organ structure are preserved (often pale and wedge-shaped)?
coagulative necrosis
What leads to coagulative necrosis?
ischemic infarction
What organ does NOT undergo coagulative necrosis after ischemic infarction?
brain (liquefactive necrosis)
What pattern of necrosis is coagulative but resembles mummified tissue?
gangrenous necrosis
What pattern of necrosis is due to enzymatic lysis of cells and protein?
Liquefactive necrosis
What two types of necrosis are seen in pancreatitis?
liquefactive necrosis of parenchyma
fat necrosis peripancreatic fat
What pattern of necrosis is soft and friable with a “cottage-cheese like appearance”?
caseous necrosis
Caseous necrosis is characteristic of which types of inflammation?
granulomatous inflammation due to Tb or fungal infection
What does fat necrosis look like?
chalky white due to deposition of calcium
What is saponification?
example of dystrophic calcification in which calcium deposits on dead tissue (in the setting of NORMAL serum calcium and phosphate)
What causes endometrial shedding (cellular level) during menses?
apoptosis
What happens to virally infected cells?
recognized by CD8+ T cells and signaled to undergo apoptosis
Why is apoptosis NOT followed by inflammaiton?
apoptotic bodies are consumed by macrophages
What is the MAJOR mediator of apoptosis? What does it do?
caspases (activate proteases that break down the cytoskeleton and activates endonucleases that break down DNA)
List the 3 pathways of apoptosis.
- Intrinsic mitochondrial pathway
- Extrinsic receptor-ligand pathway
- CD8+ T cell-mediated pathway
What is involved in the intrinsic mitochondrial pathway of apoptosis?
Bcl2 inactivated by stress, Cytochrone c is allowed to leak from mitochondria to the cytoplasm to activate caspases
What is involved in the extrinsic receptor-ligand pathway of apoptosis?
FAS ligand binds FAS death receptor (CD95) on target cell and activates caspases OR TNF binds to TNFR on target cell and activates caspases
What is involved in the CD8+ T cell-mediated pathway of apoptosis?
CD8+ T cells recognize Ag on MHC Class 1, release perforins to create pores in membrane of target cells and granzymes to enter these pores and activate caspases
What is the most damaging free radical?
hydroxyl free radical
What causes oxygen to become superoxide?
partial reduction
What causes superoxide to become hydrogen peroxide?
superoxide dismutase
What causes hydrogen peroxide to become hydroxyl free radical?
catalase
What causes Hydroxyl free radical to change into H2O and GS-SG?
Glutathione Peroxidase
Why does CCl4 lead to fatty change in the liver?
decreased apolipoprotein synthesis occurs (due to cellular injury) and fat is allowed into the liver but cannot get out
What are the 2 major features shared by all amyloid?
- Beta-pleated sheet configuration
- Congo red staining and apple green birefringence with polarized light
What is deposited in primary amyloidosis?
AL amyloid (from immunoglobulin light chain)
What is deposited in secondary amyloidosis?
AA amyloid (from SAA acute phase reactant)
In what AR disease do you see an increase in SAA and increaed risk of AA amyloidosis?
Familial Mediterranean Fever (mimics serosal inflammation like appendicitis)
What is the most common organ involved in amyloidosis?
Kidney (nephrotic syndrome)
What is deposited in Senile cardiac amyloidosis?
non-mutated serum transthyretin
What is deposited in familial amyloid cardiomyopathy?
mutated serum transthyretin
What is deposited in Alzheimer disease?
A-beta amyloid
What is deposited in dialysis-associated amyloid?
beta-2 microglobulin (what supports MHC class 1)
How do you biopsy the thyroid?
fine needle aspiration
