Chapter 3 Robbins/Pathoma Flashcards
C reactive protein is involved in what pathology?
Fibrinogen does what? what is this the basis of?
increased risk for myocardial infarction
causes RBCs to form stacks (rouleaux) that sediment more rapidly –> basis for erythrocyte sedimentation rate
What are the growth factors associated with angiogenesis
VEGF-A –> migration and proliferation of endothelial cells
NO –> vasodilation and formation of vascular lumen
FGF-2 –> proliferation of endothelial cells and helps get macrophages and fibroblasts to the area
Angiopoietins 1 and 2 –> structural maturation of new vessels
Eosinophils are abundant in immune reactions mediated by what?
what else do they have that helps destroy helminths?
IgE
major basic protein
when fibroblasts are added to the scarring tissue, what do some become and what does this help do?
they become smooth muscle like, and are called myofibroblasts –> contribute to the contraction of the scar over time
**contraction meaning reduction in size
What are the different CD4 cells and what do they produce?
Th1 –> IFN-gamma –> activates macrophages in the classical pathway
TH2 –> IL4,5,13 –> activate eosinophils and is needed for alternative pathway
Th17 –> IL-17 –> recruit neutrophils and monocytes
1) what’s the biggest cause of delay in healing?
2) what is the most important systemic cause of abnormal wound healing?
3) pirates??
4) what mechanical factors can you think of?
Infection –> the biggest one
Diabetes –> most important systemic causes of abnormal
Vitamin C deficiency –> low collagen synthesis so good luck closing that wound
someone on bedrest that doesn’t listen and opens their knee wound
what is PGE2 famous for?
what else can lead to one of these symptoms?
Pain and fever
bradykinin
Which macrophage initiates tissue repair?
which ingests and eliminates microbes?
which secrete mediators of inflammation?
M2
M1
M1
Explain the creation of prostaglandins from arachidonic acid, the different types and what they do?
(4 major things)
arachidonic acid uses cyclooxygenase –> COX1 is constitutively expressed, but COX2 is upregulated during inflammation
PGD2, PGE2 –> vasodilation
PGI2 (prostacyclin) –> vasodilator and potent INHIBITOR of platelet aggregation
Thromboxane A2 –> platelet aggregating agent and vasoconstrictor
explain Leukocyte adhesion deficiency
1) what is the problem
2) hallmarks?
3) what is the clinical feature?
autosomal recessive defect of integrins –> CD18 subunit specifically.. so you can’t adhere to the surface and be pulled in
1) delayed separation of the umbilical cord (normally the tissue dies and falls off on its own but it’ll be delayed without neutrophils
2) Increasing circulating neutrophils (half of the pool is usually adhered in the lungs.. called the marginated pool.. but they’re not adhered anymore
3) recurrent bacterial infections that LACK PUS
What is Serous Inflammation?
what is an example?
exudation of cell poor fluid into spaces created by cell injury
**skin blister resulting from a burn or viral infection represents accumulation of serous fluid beneath the damaged epidermis
Explain engulfment and what is involved
bound to phagocyte receptor –> pseudopods extend around it to become a phagosome –> binds with a lysosome –> now called a phagolysosome –> degrades it.
What do CD4 cells recognize? (mnemonic)
how does the CD4 cell bind to the APC? (mnemonic)
what about CD8?
4 x 2 = 8
CD4 recognizes MHCII
CD28 on the T cell binds to B7 on the antigen receptor cell. 28 / 7 = 4.. CD4
8 x 1 = 8
CD8 recognizes MHCI
Explain the production of ROS starting from O2
1) starting from O2, what is this step called? what enzyme is famous here?
2) from here, what is created?
3) finally, how does this get to bleach?
4) which one of these steps is the most efficient system for neutrophils?
O2 –> O2- (this is called the respiratory burst, and uses NADPH Oxidase
O2- –> H2O2 (spontaneous)
H2O2 –> HOCL (bleach) via Myeloperoxidase (MPO)
MPO/HOCL system is most efficient
What is Leukocytosis?
why is there so many of these?
what kind of leukocytes are there more of? what is this called physiologically
also referred to as Leukemia reactions –> they are similar to the white cell counts observed in leukemia and have to be distinguished from that.
there’s an accelerated release of bone marrow post mitotic reserve pool (caused by IL1 and TNF)
tons of immature neutrophils –> left shift
What is Purulent (suppurative) inflammation?
common example of this?
what are localized collections of purulent inflammatory tissue called? what do they look like histologically?
characterized by production of pus, an exudate consisting of neutrophils, liquefactive debris of necrotic cells, and edema fluid
acute appendicitis
abscesses –> central region that appears as a mass of necrotic leukocytes and tissues, surrounded by a layer of preserved neutrophils
How does fever happen?
IL1 and TNF get into the blood stream, hit the perivascular cells of the hypothalamus
they up regulate COX activity which increases PGE2, raising the set point of the hypothalamus
What is the most successful therapeutic for people with chronic inflammatory disease?
what are examples of this?
TNF inhibitors.. it’s preventing leukocyte recruitment!
RA or psoriasis or IBD
why is nitric oxide considered a free radical?
how is NO created?
which is the only one associated with microbial killing?
NO + O2- superoxide –> ONOO-
via NOS –> eNOS (endothelial), nNOS (neuronal), iNOS (inducible)
iNOS
why can neutrophils be found in a chronic state? what’s an example?
neutrophilic exudate can persist for many months.
Osteomyelitis
called “acute on chronic”
Explain Liver regeneration
1) start with hepatocyte proliferation.. what is this triggered by and what are the phases?
Hepatocyte proliferation in the regenerating liver is triggered by:
1) priming phase –> IL6 is released from Kupffer cells to prime hepatocytes
2) growth factor phase –> HGF and TGF-a act on primed hepatocytes to put them into the cell cycle (because they’re quiescent remember)
3) Termination phase –> after divisions, they return to quiescent.
What are the five cardinal signs of inflammation?
rubor (redness) tumor (swelling) calor (heat) dolor (pain) functio laesa (loss of function)
What is an ulcer?
where is it most commonly encountered?
local defect, or excavation, or the surface of an organ that is produced by the sloughing of inflamed necrotic tissue
mucosa of the mouth, stomach, intestines, GI (peptic ulcers)
lower extremities of people who have circulatory disturbances
What are the major signs of acute inflammation?
what is causing each?
redness and warmth –> vasodilation, mediated by histamine, PGI2,D2,E2, bradykinin
swelling –> leakage of fluid from post capillary venules (histamine and tissue damage)
pain –> PGE2 + Bradykinin
Fever –> macrophages releasing IL1 and TNF
What are the 3 main growth factors helping to lay down connective tissue for scars?
where do they come from?
what’s the most important one?
PDGF, FGF-2, and TGF-B
M2 macrophages
TGF-B
What is exudate?
what is causing it?
what is an example?
what is transudate?
what is causing it?
what is an example?
extravascular fluid high in protein and contains cellular debris.. this is due to fluid and protein leakage.
**pus is a purulent exudate consisting of dead leukocytes and microbes
Transudate is a fluid with LOW protein content and LOW cellular material.. fluid leaks out due to an increased hydrostatic pressure or decreased oncotic pressure
**edema is considered an ultra filtrate
Most bacterial infections have local inflammation. in rare cases it can go systemic. what is this this called?
Sepsis, which is a form of systemic inflammatory response syndrome
What are the phagocytic receptors?
why are the ones on macrophages not self reactive?
what enhances the phagocytosis of stuff? what if this weren’t around? what are the specific ones to know?
Mannose receptor on the macrophage –> mammalian glycoprotein do not have terminal mannose on their cell membranes, bacteria do
Mac-1 –> integrin on macrophages that may also bind.
opsonins –> IgG and C3b
nonselective without it, kind of directs it to the area.
What is the oxygen independent form of microbial killing?
what two things should we know?
is it more or less effective for oxygen dependent?
secondary granules contain lysozyme and major basic protein
less effective by a lot.
What does IL6 do? where does it come from?
What about IL17?
Made by macrophages –> local and systemic reactions
IL-17 –> produced by T lymphocytes –> neutrophil recruitment
What are the four causes of inflammation?
Infection –> most common cause
Tissue necrosis –> remember inflammation follows necrosis
foreign bodies (splinters, dirt, sutures)
immune reactions (hypersensitivity reactions and autoimmune diseases) –> this is more for chronic
What are neutrophil extracellular traps?
what happens to the neutrophils because of these traps?
extracellular fibrillar networks that provide a high concentration of antimicrobial substances at the site of infection and prevent spread of infection by trapping them to the fibrils.
nuclei are lost during the formation of the nets, so their death
What is the response of lymphatics in inflammation? why is it happening?
what is a telltale sign of an infection in the wound with regards to lymphatics? diagnosis?
lymph flow increases to help drain edema fluid
red streaks near a skin wound –> lymphangitis (inflamed lymphatic vessels)
What is “the acute phase response”
what is included within this?
cytokine-indued systemic reactions
Fever Acute-Phase proteins Leukocytosis increased BP/pulse sepsis if severe
which CD4 cell is important for defense against helminths?
Th2
What cell plays a central role in repair by clearing offending agents and dead tissue? Be specific!
Macrophages (M2)
what do we use to inhibit thromboxane A2 or prostaglandins?
what if we want to inhibit just COX2? is that good or bad?
COX1 and COX2 inhibitors (or aspirin)
bad –> cox-2 is used primarily for prostacyclin, so if you inhibit that it could tip the scale to more thromboxane A2 leading to more vascular thrombosis
Wound contraction happens primarily in what kinds of wounds
large wounds