Necrosis and Atherosclerosis

Question 1

what are the 2 pathways for cell death?

Answer 1

apoptosis (planned)

necrosis (pathological)

Question 2

What are some unique features of necrosis?

Answer 2

swelling and karyolysis

Question 3

What are some unique features of apoptosis?

Answer 3

shrinkage and apoptotic bodies

Question 4

How can ischemia lead to necrosis?

Answer 4

mitochondria damage, increased glycolysis and running out of ATP

sodium pump stops working (needs ATP)

osmosis causes cell to start to swell

Question 5

coagulative necrosis

Answer 5

architecture of cell is preserved but cell contents are condensed and hyperdense

this causes cell to stain eosinophilic

Question 6

liquefactive necrosis

Answer 6

complete loss of cell and tissue architecture

creates pus in infection

Question 7

Where does liquefactive necrosis always take place?

Answer 7

the brain

Question 8

What type of necrosis creates abscesses?

Answer 8

liquefactive necrosis

Question 9

What type of necrosis creates granuloma?

Answer 9

caseous necrosis

Question 10

caseous necrosis

Answer 10

cannot clear pathogen so you in case it in layers of fibroblasts to wall it off

looks like cheese in gross anatomy

Question 11

common cause of caseous necrosis

Answer 11

TB

Question 12

where does saponification occur? and specifically?

Answer 12

fat necrosis

specifically, pancreatitis

Question 13

How does fat necrosis appear? Why

Answer 13

appears basophilic due to accumulation of calcium lipid salts

Question 14

fibrinoid necrosis

Answer 14

fibrin leaks into vessels

fibrin stains bright pink

often due to autoimmune disease attacking vessel walls

Question 15

wet gangrene is caused by …

Answer 15

liquefactive necrosis

Question 16

dry gangrene is caused by …

Answer 16

coagulative necrosis

Question 17

how can you differentiate apoptotic bodies from blebs

Answer 17

apoptotic bodies are rounder and nicer looking

Question 18

what type of cell clears apoptotic bodies?

Answer 18

macrophages

Question 19

what is a chemotactic factor released by apoptotic cells? what do they attract?

Answer 19

ADP / UTP produced by connexon channels

attract macrophages

Question 20

Does apoptosis produce an inflammatory response?

Answer 20

no, for this reason it is considered “sterile”

Question 21

what serves as signal for phagocytosis in apoptosis cell?

Answer 21

phosphatidyl serine (PS)

Question 22

What class of enzyme is the critical effector molecule for apoptosis?

Answer 22

Caspases

Question 23

What is the active site of caspases?

Answer 23

cysteine

Question 24

How do you active caspases?

Answer 24

need to cleave them

Question 25

3 isoforms of caspases to know

Answer 25

3, 8, 9

Question 26

What can caspase activation lead to?

Answer 26

organellar fragmentation, translational shutdown, actin depolymerization, detachment of cells from ECM and inactivation of flipases

Question 27

Intrinsinc pathway of apoptosis

Answer 27

mitochondrial damage and formation of apoptosome *also recognize cytochrome C as part of this

Question 28

Extrinsic pathway of apoptosis

Answer 28

DISC (death inducing complex) caspase 8 binding of death ligands NK cells and cytotoxic T cells can signal extrinsic, death, pathway

Question 29

What is common between intrinsinc and extrinsic apoptosis pathways?

Answer 29

caspase 3

Question 30

What cells express the FasL ligand to trigger the extrinsic death pathway?

Answer 30

NK cells and activated T-cells

Question 31

Caspase 9 is part of ...

Answer 31

intrinsic (mitochrondrial) apoptosis pathway

Question 32

Caspase 8 is part of ...

Answer 32

extrinsic apoptosis pathway

Question 33

Caspase 3 is part of ...

Answer 33

both intrinsic and extrinsic apoptosis pathway

Question 34

Which requires ATP, apoptosis or necrosis?

Answer 34

apoptosis

Question 35

Difference between ischemia and infarction

Answer 35

infarction is irreversible injury

Question 36

white infarct

Answer 36

not hemorrhagic typically seen in dense tissues (heart + kidneys)

Question 37

red infact

Answer 37

has some collateral blood flow blood is able to re-enter the tissue to some extent

Question 38

What type of vessels does atherosclerosis occur in?

Answer 38

arteries only

Question 39

6 steps of forming an atherosclerotic plaque

Answer 39

1) endothelial injury 2) endothelial dysfunction leading to monocytes and platelet adhesion 3) macrophage activation and smooth muscle recruitment 4) accumulation of cholesterol in intima and foam cells 5) smooth muscle proliferation and deposition of ECM 6) formation of distinct fibrous cap and necrotic center

Question 40

Where do plaques commonly form?

Answer 40

at turbulent flow sites

Question 41

difference between pathogenesis and etiology

Answer 41

pathogenesis: process by which disease develops etiology: cause of disease

Question 42

How do foam cells form?

Answer 42

LDL is transported across endothelial barrier LDL particles are oxidized in region of forming atheroma Oxidized LDL are taken up by macrophages forming smooth muscle cells Foam cells release growth factors and cytokines which recruit additional monocytes/smooth muscle cells to plaque

Question 43

transcytosis

Answer 43

transporting LDL across endothelial barrier

Question 44

What is the earliest lesion seen in formation of atherosclerotic plaque?

Answer 44

fatty streak *does not always form atherosclerosis*

Question 45

primary cellular component of fatty streak?

Answer 45

foam cells

Question 46

where is fatty streak?

Answer 46

subendothelial

Question 47

2 parts of atherosclerosis

Answer 47

1) necrotic center 2) fibrous cap

Question 48

what can lead to thrombosis?

Answer 48

an ulcerated atherosclerotic plaque

Question 49

nitroglycerin

Answer 49

nitrogen oxide activates guanyl-cyclases which causes vasodilation of chest vessels

Question 50

how does area of infarct stain?

Answer 50

stains blue on trichrome due to replacement by connective tissue in infarcted area