Adaptation, Injury, Death and Systematic Approach to Disease - Prestudy Flashcards
What is ischemia?
REVERSIBLE injury due to inadequate blood supply
What is infarction?
IRREVERSIBLE necrosis due to ischemia not relieved in time
How should liquefactive necrosis be treated?
drainage
How should caseous necrosis be treated?
anti-fungal and anti-TB treatments
How should gangrenous necrosis be treated?
amputation
What things is pathologic apoptosis important in?
certain cancers, chemotherapy, radiation, and transplant rejection
Define etiology
doctorspeak for “cause”
define morphology
pathologistspeak for “visible manifestation”
Define “gross”
pathologistspeak for “visible without a microscope”
What is the difference between adaptation and injury?
Adaptation - body responds and develops a new homeostasis in which it can survive
Injury - reversible pathophysiologic and morphologic response to stress that exceeds the capacity of a cell/tissue to adapt, but is not lethal.
Define hypereosinophilia
excess of eosinophils, a type of granular containing white blood cells.
What happens to cellular ATP and ROS levels during mitochondrial damage? What would Ca do? What else occurs?
ATP drops and ROS (reactive oxygen species) increases. Ca2+ enters the cell cell in excess.
Protein misfolding and membrane degradation
During ischemia, mitochondrial activity decreases, resulting in low ATP levels. How does this affect Na+, Ca2+, and H20 levels?
Na+ pump doesn’t have energy to run so Na can not be pumped out and it builds up inside the cell. Similarly, K+ is no longer being forced into cell so K+ effluxs out.
Ca2+ will begin to influx into the cell.
Net ion concentration increases and cell begins to swell with H20.
What change would you expect in pH in an ischemic cell?
pH will drop and become more acidic because of anaerobic glycolysis, which produces lactic acid.
What are the effects of increased cytosolic Ca2+?
activation of proteases, phospholipases, and endonucleases cause membrane and nuclear damage.
ATPase activation (as well as the influx of Ca2+ from the cytosol to the mitochondria) will decrease ATP production, causing further damage.
How can reperfusion (the restoration of blood to ischemic cells) cause further injury?
The newly restored blood brings oxygen, which is necessary, but can be converted to ROS which can cause further damage.
New blood can also increase Ca2+ levels, causing further inappropriate enzyme activation and mitochondrial permeability.
The presence of amylase in blood is indicative of what?
necrosis of pancreatic, duedenal, or salivary gland cells
The presesnce of lipase in retroperitoneal fat is indicative of what?
pancreatitis (pancreas necrosis)
What compound would you expect to find in the blood after myocardial injury?
CPK MB fractions (creatine phosphokinase M and B dimers)
What are troponins? When would you find them in the blood stream?
proteins that regulate Ca-mediated contraction of cardiac and skeletal muscle.
Can be released into blood after myocardial injury
What is ALT? What does it do? When would its blood concentration increase significantly?
ALT is alanine aminotransferase, a transaminase that converts Glu to Ala.
Release into blood after liver injury.
What is AST? What does it do? When would its blood concentration increase significantly?
AST is aspartate aminotransferase, which converts Glu and Asp.
It is released after muscle, liver and other organ injury.
What would be released more after liver injury: ALT or AST?
ALT
What is ALP? What does it do? What pathologies would cause it to be released into blood?
ALP is alkaline phosphatase, which transfer P04 from donors to receptors at basic pHs.
It is released into blood by liver, bone, especially biliary obstruction or hepatic space-occupying disease. Cholestasis
What is GGT? What does it do? What pathologies would cause it to be released into blood?
GGT is gammaglutamyl-transferase, an outer cell membrane enzyme that transports AA’s into cells.
Released by liver injury (especially toxic injuries)
What is LDH? What does it do? What pathologies would cause it to be released into blood?
LDH is lactate dehydrogenase, which converts lactate to pyruvate by removing two hydrogens.
Released by injury to blood cells, liver, muscle, or other organs.
Define coagulative necrosis.
Morphological manifestation of irreversible injury to cell, tissue or organ due to ischemia (except in brain)
Which organ is most vulnerable to ischemia? What timeframe before infarction?
The brain. Infarction after 3 min.
Approximately how long can the heart withstand ischemia?
20 min
Approximately how long can the liver withstand ischemia?
2 hours
What features would you expect to find in tissue that has undergone coagulative necrosis?
preservation of the ghost cell outline.
increase in pink eosinophilia in cytoplasm.
pyknosis of nucleus (increased blue basophilia and shrinkage).
Nucleus Karyorrhexis (fragmentation)
Nucleus Karyolysis (fading away)
Acute inflammatory response
Which is more likely to be damaged by ischemia: renal tubules or glomeruli? Why?
The renal tubules are much more susceptible to ischemic injury and necrosis because the glomeruli recieve blood first, then it passes to the renal tubules.
Ischemia is not relieved in brain. What type of necrosis will likely occur?
liquefactive necrosis
Ischemia in tissue outside the brain is not relieved; what type of necrosis will likely occur?
coagulative necrosis
Severe infection damages tissue; what type of necrosis is likely?
liquefactive necrosis or caseous necrosis
What is an abscess?
localized area of liquefactive necrosis
A micronecrosis is eosinophilic and lacks ghost cell outlines. What type of necrosis is it?
Caseous. Lack of ghost cell outlines.
Describe gangrene
a type of coagulative necrosis where the tissue turns black and shrinks