Wk 9 Block Flashcards
Eosinophils are activated by ___ during multicellular parasitic infection?
IgG and IgA - coat the parasite and activate eosinophils (antibody dependent cell mediated cytotoxicity)
Eosinophils contribute to what part of the Type 1 HS rxn?
Late phase - synthesize prostaglandins, leukotrienes and cytokines.
Ankylosing spondylitis is an inflammatory spondyloarthropathy characterized by simultaneous?
Erosion of bone and new bone formation. New bone formation happens at the periosteum-cartilage junction -> bridging syndemophytes in the vertebral column.
Cancer located in the nasopharynx can lead to obstruction of the?
Eustachian tube (connects middle ear to nasopharynx)
Patients started on testosterone therapy should monitor this value?
Hematocrit (testosterone therapy can cause erythrocytosis)
How do combination oral contraceptive work?
Suppress GnRh and pituitary secretion of gonadotropins -> inhibits ovulation
Phosphorylation of ____ & ____ residues of insulin receptors leads to insulin resistance?
Serine and threonine (via activation of serine kinases)
**inhibits downstream signalling of insulin
REM sleep is characterized by (2)?
When does it typically occur?
dreaming (nightmares) and muscle paralysis
Final third of the night
**EEG is similar to waking state -> combination of alpha, beta and desynchronus waves (sawtooth waves)
DIfferentiate REM sleep from sleep tremors?
Sleep tremors is a non -REM parasomnia - incomplete arousal and lack of recall of dream content
Function of IL-8?
Chemokine produced by macrophages -> induce chemotaxis and phagocytosis in neutrophils
HPV has a predilection for this type of surfaces?
stratified squamous epithelium
(found in the anal canal, vagina, cervix) and in the true vocal cords in the respiratory tract.
**squamous epithelium are located in paces that undergo constant friction and abrasion
Procalcitonin is an acute phase reactant that elevate with ___ infections?
Bacterial (levels are low in viral infections)
if a pts neutrophils fail to turn blue following exposure to nitroblue tetrazolium, what does this mean?
Indicative if Chronic granulomatous disease - caused by X-linked mutation to NADPH oxidase -> impaired intracellular killing by neutrophil and macrophages.
**infections are often caused by catalase-[positive organism
Alcohol based disinfectants kill ___ viruses?
Enveloped ** it dissolves their outer lipid envelope.
What can cause toxic shock syndrome?
Tampons or wound packing (allows for S. aureus to replicate locally and release pyrogenic toxic super antigens)
Toxic shock syndrome toxin 1 (super antigens) bind to _____ complex of APC?
Super-antigens binds to MHC II w/o processing and non selectively activates T cells -> inflammatory cytokines -> dz manifestations
Ganclyclovir adverse effect?
Neutropenina, anemia, and thrombocytopenina (also blocks host DNA polymerase)
What organisms are resistant to cephalosporins?
Listeria, MRSA, Enterococci ( resistant PBPs)
Atypicals (Mycoplasma, Chlamydia) - no cell wall.
The biofilm in S. epidermis is made up of?
extracellular polysaccharide matrix
H. influenza ca grow when sheep blood is cross streak with S. aureus because?
B-hemolysis allows production of factors V (NAD+) and X.
Pharyngeal is often present in people with impaired _____ immunity?
Cell-mediated (immunosuppresed)
Inactivated (killed or component) viral vaccines generate a ___ response against viral antigens?
humoral response. Prevents viral entry into cells
** neutralizing Abs to hemagluttinin
Live attenuated viral vaccines generate a _____ response?
Strong cell mediated immune response that kills virally infected cells + humoral immunity
Aminoglycoside resistance is most commonly due to?
Antibiotic modifying enzymes (these enzymes add chemical groups to the antibiotic - diminishes ability to bind to 16S rRNA withing 30s ribosmal unit.)
Suppurative (bacterial) parotitis cane present with elevated levels of?
Amylase (parotid gland secretes this)
**this condition occurs in elderly intubated and dehydrated (post -op) patients
Suppurative parotitis is often caused by this bacteria?
S. aureus
How does S. aureus become methicillin resistant?
acquisition of mobile genetic element that contains mecA gene -> codes for specialized PBP that have low affinity fro B-lactam antibiotics.
Apart from hijacking the acting apparatus, what is listerias other virulence factors?
Listeriolysin O -> creates pores in phagosome memebrane -> allows for phagocytised bacteria to escape into the cytoplasm of monocytes and avoid lysosomal destruction.
Explain phenotypic mixing?
Coinfection of host cells with 2 viral strains -> mix -> release virions that contain mixture of both -> but progeny reverts back to original strain since no change in underlying viral genomes (no genetic exchange).
Conversion from non toxigenic to toxigenic C diphteria occurs due to ?
infection with lysogenic bacteriophage - (cornephage beta) -> inserts tox gene -> expression of diphtheria AB toxin -> halts synthesis via ribosylation.
