Shared Flashcard Set

Details

7. Kane lecture 11/12
BrownMed
42
Anatomy
2nd Grade
11/13/2010

Additional Anatomy Flashcards

 


 

Cards

Term
the major pathways of acetaminophen metabolism are (2) / children vs. adults
Definition
glucuronidation and sulfation / children are mainly sulfation, adolescents/adults are mainly glu
Term
if CYP2E1 activity is induced, acetaminophen metabolism is shifted to / which does what
Definition
P450 system that generates a highly reactive intermediate that binds to and depletes GSH. people with decreased GSH are more susceptible to acetaminophen toxicity
Term
how do you get decreased stores of GSH (2)
Definition
fasting (kids who don't feel well don't eat), chronic alcoholism
Term
hepatotoxicity of acetaminophen / pathology / treatment
Definition
2-4 days after ingestion / centrilobular necrosis / n-acetylcysteine (is swallowed and converted to cysteine, which replenishes GSH stores and also detoxifies the acetaminophen reactive intermediate)
Term
children are _ susceptible to acetaminophen toxicity. _ margin of safety between therapeutic and toxic
Definition
more, narrow
Term
most common reason for liver transplantation in the US
Definition
acetaminophen overdose
Term
aspirin
Definition
(acetylsalicylic acid) knocks out urea cycle > cerebral edema > coma (Reye syndrome)
Term
salicylates
Definition
(aspirin) toxic to mito, especially in children w/ fever because of the release of cytokines
Term
mito injury > >
Definition
ATP depletion / decreased FA oxidation > microvesicular fatty change (Reye syndrome)
Term
acute effects of ethanol
Definition
mainly on CNS - depressant, directly affecting membrane fluidity
Term
chronic effects of ethanol are mediated by several mechanisms (4)
Definition
1. direct toxicity of alcohola nd its metabolites: acetaldehyde can induce lipid peroxidation and form protein adducts. 2. free radicals as by-prodcuts during metabolism by p450 3. excess use of ethanol can displace consumption of other nutrients and vitamins - this is important in the chronic neurologic effects of ethanol. 4. induction of p450 induces metabolism of drugs and chemicals to toxic intermediates
Term
alcoholic cirrhosis / accompanied by (4)
Definition
irreversible. micronodular (fibrosis in between regenerating aggregates of hepatocytes) w/ fatty change. / muscle wasting, weakness, ascites, tendency for massive GI hemorrhage (because clotting factors are low)
Term
potential mechanism for fibrous scarring in liver damage
Definition
conversion of stellate cells (mesenchymal cells filled with lipid in the space of Disse) to fibroblasts
Term
stimulation of collagen synthesis in liver may be caused by
Definition
the same mediators of peptide growth factors responsible for fibrous scar formation in a healing wound
Term
chronic alcoholics are highly susceptible to _-induced liver injury at _ doses
Definition
acetaminophen / therapeutic
Term
difference between hypoxia and ischemia
Definition
ischemia prevents nutrients as well as oxygen from getting to tissues
Term
biochemical lesions in ischemia are (3)
Definition
ATP depletion, mitochondrial damage, plasma membrane damage (overloading of calcium)
Term
time it takes to kill a heart/brain cell
Definition
heart - 20-30 minutes no O2; brain - 2-3 minutes
Term
leading cause of death in developed countries
Definition
ischemic heart disease
Term
biochemical events in ischemia
Definition
decreased oxidative phosphorylation in mito leads to less ATP, which leads to inactive sodium pump, increased anaerobic glycolysis and detachment of ribosomes
Term
consequences of inactive sodium pump
Definition
influx of calcium, water and sodium (and efflux of potassium) leads to ER swelling, cellular swelling, and loss of microvilli blebs
Term
consequences of increased anaerobic glycolysis
Definition
decreased glycogen. increased lactic acid = decreased pH = clumping of nuclear chromatin
Term
consequences of detachment of ribosomes
Definition
decreased protein synthesis
Term
ATP is synthesized as a result of
Definition
oxidative phosphorylation of ADP in the mitochondrial membrane
Term
ATP can also be synthesized by
Definition
the Embden-Meyerhof glycolytic pathway in the cytoplasm
Term
what happens biochemically in ischemia to stop ATP production
Definition
cytochrome C can't convert oxygen to water because there is no oxygen; complex V (ATP synthase) is never reached
Term
cyt C causes apoptosis (instead of ischemic necrosis) by activating Apaf-1 IF
Definition
there's OMM damage AND ATP is still being made
Term
mitochondria dysfunction and membrane damage in ischemia
Definition
decreased phospholipid synthesis/recycling = phospholipid degradation and loss to lipid breakdown products. increased cytosolic calcium activates phospholipases which also break down PLs, and activates proteases which damage the cytoskeleton
Term
increased cytosolic calcium activates / resulting in
Definition
phospholipase A2 / degradation of membrane phospholipids
Term
oxidative mitochondrial damage >
Definition
mitochondrial permeability transition
Term
detergent effect of FFA
Definition
accompanied by phospholipid damage. induces loss of permeability barrier and massive calcium influx and calcium precipitates
Term
free radical attack on membrane
Definition
lipid peroxidation
Term
activation of phospholipases >
Definition
detergent effect of FFA; loss of permeability barrier to calcium
Term
see p. 41,42,44 in this lecture
Definition
Term
coagulation necrosis / influx of
Definition
= ischemic damage (coagulation in vessels causes necrosis) / neutrophils
Term
effect of decreased ATP on proteins
Definition
denatures them; loss of intracellular amino acids leads to cell membrane damage
Term
extensive necrosis in heart can cause _ which does what?
Definition
shock, which causes lack of myocardial motility in the healthy cells left
Term
3-5 days after myocardial infarct
Definition
neutrophils. nuclei of myocardial cells are lysing so the membranes are fuzzy
Term
these 3 enzymes are used as clinical markers for myocardial infarction (because they are released when cells lyse) / time frames
Definition
creatine kinase (starts 2-4hrs, peaks 24-48hrs, disappears by 72 hours), lactate dehydrogenase (after creatine kinase), troponins (starts 2-4hrs, remain elevated 7-10days)
Term
reperfusion injury is mediated by (3)
Definition
influx of neutrophils in blood, generation of ROS, and apoptosis of myocardial cells surrounding the necrotic cells damaged by ischemia
Term
internal oxidation from _ and external oxidation from _ may be enough to induce _ where?
Definition
mitochondria, neutrophils, apoptosis at periphery of ischemic injury
Term
what type of tissue is fibrosis
Definition
collagen type 1 scar tissue. fills in holes where dead tissue was
Supporting users have an ad free experience!