Exam I (August 15) Review Flashcards
Will albumin increase or decrease during chronic inflammation? Why?
decrease in albumin synthesis and increased hepatic production of fibrinogen, ceruloplasmin, complement components (C3)
How are hepcidin and anemia related?
hepatocytes increase levels of hepcidin during inflammation can cause anemia bc hepcidin decreases absorption of iron in gut (hoping to prevent microbial access to iron)
If a patient presents with leukocytosis and thrombocytosis, what might this indicate? What tests should you run?
During inflammation, healing process begins, growth factors secreted, growth factors stimulate marrow
- increased leukocyte production
- increased platelet production
(leading to possible leukocytosis and thrombocytosis)
indicates inflammation…do CRP test
What would a positive CRP test indicate? Why?
What would a negative CRP test indicate?
In what clinical scenario might a CRP test be falsely elevated?
CRP (Reactive protein) is stimulated by inflammation, is tightly linked to IL-6 levels
so can be used in semi-quantitative fashion for level of inflammation (when normal can exclude significant inflammation)
absent CRP- no chronic inflammation present
Obesity is the one morbidity that can cause a “false” elevation of CRP
What is ESR? Describe the mechanism by which it works. Explain the benefits/disadvantages.
Chronic inflammation causes clinically detectable antibody synthesis expressed as polyclonal increase in IgG
IgG and fibrinogen coat erythrocytes and the red cells then fall more rapidly through a column of plasma-the rate is the ESR.
Rapidly becoming obsolescent because “false elevations” can occur when there is increased IgG present for non inflammatory reason - eg., myeloma, age
How is regeneration related to extracellular matrix?
With regeneration, the connective tissue framework (extracellular matrix) remains in tact and serves and scaffolding for replacement of residual uninjured cells (but have capacity to divide w depends on tissue type; labile, stable, permanent)
ECM is network of interstitial proteins (interstitial matrix or BM)
protein composition: fibrous structural proteins (collagen, elastins)
water hydrated gels (proteogylcans, hyaluronan), adhesive glycoproteins
BM: type IV collagen, laminin, proteoglycan
interstitial matrix: fibrilar collagens, elastin, proteoglycan and hyaluronan
Which growth factor will stimulate the production of epithelial cells and hepatocytes?
TGF alpha
What would a mutation in VEGF lead to?
normal function: angiogenesis, endothelial cell migration and proliferation, increases vascular permeability
mutation: defective angiogenesis and vasculogenesis
VEGF is expressed at low levels in most adult tissues, where are the exceptions?
expressed at higher levels in podocytes in glomerulus and pigment epithelium of retina
A patient on glucocorticoids receives a deep laceration on the arm. How might the drug interact with the healing process?
glucocorticoids are anti-inflammatory, inhibit TGF-beta production
TGF-beta has a role in fibroblast recruitment and angiogenesis, stimulates ECM synthesis
(so glucocorticoids can prod a v abnormal response to healing - need inflammation to start healing process)
A patient fell off her bike earlier in the afternoon and has been waiting in the ER for a few hours. You see her and run some labs. They show low platelet and RBC count. Examining the patients you notice small red dots on their skin. What could this indicate?
Fat and Marrow Emboli develop in patients with severe skeletal injuries
-“Fat Embolism” syndrome is systemic (pulmonary insufficiency, neurologic
-Symptoms, anemia, thrombocytopenia, petechial rash)
Fatal in up to 10% of patients
What are the important mediators for angiogenesis?
VEGF
FGFs, PDGF, TGF-beta
What are pericytes?
a growth factor stimulates pericytes and endothelial cell formation;
pericytes have ability to stimulate endothelial stem cells to proliferate, stimulate the endothelium to mature
What do fibroblasts do? How are they recruited?
synthesize connective tissue proteins
Recruitment, activation driven by many growth factors (PDGF, FGF, TGF−beta)
What is organization?
Definition: Process of transforming granulation tissue into a dense scar
With time blood vessels become less prominent, collagen matures (type III collagen replaced by type I collagen)
Trichrome stain
stains mature (type I) collagen blue
What is the primary mechanism of repair in healing by first intention and second intention?
first intention - epithelial regeneration
second intention- myofibroblasts
