missed questions, review Flashcards
eosinophils contribute to parasite defense via…..
immediate hypersensitivity
via IgE/mast cell system: stimulated mast cells chemoattract eosinophils
neutrophilia is characteristic of _______ infections
eosinophilia is characteristic of _______ infections
neutrophilia = bacterial infections
eosinophilia = parasitic infections
burn blister is an example of _____ inflammation
serous inflammation - produces serum-like exudate due to increased vascular permeability
fat necrosis occurs when….
pancreatic acinar cells release lipase
antigenic vs immunogenic
antigenic: stimulates production of and binds antibodies
immunogenic: induces immune response
if a person received a tetanus booster 10 years ago and comes to your office today with a deep cut, what should they be given?
only tetanus toxoid (booster) to stimulate immune cells
they do not need immunoglobins because they still have memory cells that will quickly jump into action
_____ rejection can occur weeks/months/years after transplant, and is characterized by CD8+ T cell infiltration
bonus: how do you treat it?
acute cellular rejection - treat with corticosteroids
what are characteristic features of chronic rejection
interstitial fibrosis and blood vessel thickening
what is characteristic of hyperacute rejection (within minutes)
fibrinoid necrosis and thrombosis
T/F: passive transfer (adoptive immunity) of sensitized T cells does not produce protection
passive transfer (adoptive immunity) of sensitized T cells does NOT produce protection ALONE (need to be activated by MHC)
which of these is NOT a mechanism of Tregs?
a. central tolerance
b. cytolysis
c. inhibitory cytokines
d. metabolic disruption
e. targeting of DC
central tolerance is mediated by medullary thymic epithelial cells
stratum germinativum renews
a. epidermis
b. dermis
c. both
a. epidermis
amplification pools are key
which renews faster, thick or thin skin?
thick
liquefactive necrosis
dead tissue transforms into liquid, viscous mass (cells are dying and releasing digestive enzymes)
why can burns be life-threatening?
loss of fluids and subsequent dehydration
classically activated macrophages (M1) vs alternatively activated macrophages (M2)
M1 (via IFN-y) —> microbicidal actions (ROS, NO, lysosomal enzymes), inflammation (IL-1, IL-12, IL-23)
M2 (via IL-13, IL-14) —> anti-inflammatory (IL-10, TGFb), wound repair/fibrosis (TGFb)
where do the antibodies come from in the classical complement pathway (given that innate immunity occurs before active immunity stimulation)?
antibodies can be poly reactive IgM from marginal zone B cells, or memory Ig, or low affinity IgG made early in adaptive response (goes back to activate more complement)
explain (basically) cross-presentation
any time virus/endogenous antigen does not infect/trigger DC: MHC II converted to MHC I (exogenous antigens are taken up, now they are intercellular, and can be presented on MHC I) —> T cells activated via MHC I
can happen on any cell type
T/F: all antibodies start out as membrane bound BCR
TRUE
which are more diverse BCR or TCR
TCR !
which require processed antigens, TCR or BCR?
TCR - recognize processed antigen via MHC I or MHC II
BCR - recognize unprocessed/whole antigen
which of these is NOT a common adverse side effect of glucocorticoids?
a. osteoporosis
b. hypotension
c. muscle wasting
d. redistribution of fat
e. bacterial and opportunistic infections
b. hypotension
aspirin (acetylsalicylic acid) is cardio protective because:
a. aspirin binds irreversibly to COX-1 in platelets
b. aspirin binds selectively to COX-1 compared to COX-2
c. aspirin on promotes the formation of TXA2
d. aspirin inhibits production of PGI2
a. aspirin binds irreversibly to COX-1 in platelets
Pt is a 52yo M presenting with blisters on the back of his hands, which erupted shortly after tennis season began. Pt denies exposure to poison ivy or use of new soaps. SHx includes moderate alcohol intake. Urine sample was red-orange, and 24-hour urine showed elevated uroporphyrin. What does this indicate?
Porphyria cutanea tarda: deficiency in UROD (uroporphyrinogen decarboxylase), essentially acquired
hints: blisters, ethanol intake, exposure to sunlight (tennis), red-orange urine, uroporphyrin in urine
what is the committed step of heme synthesis?
the first step: ALAS condenses glycine + succinyl CoA into delta-aminolevulinic acid (ALA)
*remember that ALAS requires pyridoxal phosphate (vitamin B6) as a coenzyme
aminolevulinic acid synthase activity:
a. catalyzes rate-limiting reaction in porphyrin biosynthesis
b. is strongly inhibited by lead
c. is decreased in the liver in individuals treated with barbiturates
d. occurs in the cytosol
aminolevulinic acid synthase activity:
a. catalyzes rate-limiting reaction in porphyrin biosynthesis
*remember that first step of heme synthesis is the committed step, catalyzed by ALAS
which porphyria is often acquired?
PCT: deficiency in hepatic enzyme UROD (uroporphyrinogen decarboxylase), presents with skin fragility and bullae on sun-exposed sun
Pt. is 29yo F admitted to the ICU 3w after bariatric surgery with decreased level of consciousness, psychomotor agitation, confusion, abnormal pain, and proximal tetraparesis. Urine same appeared dark red and showed high levels of delta-aminolevulinic acid and porphobilinogen. What is likely diagnosis?
AIP (acute intermittent porphyria): deficiency in hepatic PBGD
hints: dark red urine, neuropathy (proximal tetraparesis), delta-aminolevulinic acid and porphobilinogen in urine, altered mental state - likely that surgery triggered the attack
which two enzymes of heme synthesis pathway does lead inhibit?
ALAD (ALA Dehydratase) and ferrochelatase