Wk 9 Block

Question 1

Eosinophils are activated by ___ during multicellular parasitic infection?

Answer 1

IgG and IgA - coat the parasite and activate eosinophils (antibody dependent cell mediated cytotoxicity)

Question 2

Eosinophils contribute to what part of the Type 1 HS rxn?

Answer 2

Late phase - synthesize prostaglandins, leukotrienes and cytokines.

Question 3

Ankylosing spondylitis is an inflammatory spondyloarthropathy characterized by simultaneous?

Answer 3

Erosion of bone and new bone formation. New bone formation happens at the periosteum-cartilage junction -> bridging syndemophytes in the vertebral column.

Question 4

Cancer located in the nasopharynx can lead to obstruction of the?

Answer 4

Eustachian tube (connects middle ear to nasopharynx)

Question 5

Patients started on testosterone therapy should monitor this value?

Answer 5

Hematocrit (testosterone therapy can cause erythrocytosis)

Question 6

How do combination oral contraceptive work?

Answer 6

Suppress GnRh and pituitary secretion of gonadotropins -> inhibits ovulation

Question 7

Phosphorylation of ____ & ____ residues of insulin receptors leads to insulin resistance?

Answer 7

Serine and threonine (via activation of serine kinases)

**inhibits downstream signalling of insulin

Question 8

REM sleep is characterized by (2)?

When does it typically occur?

Answer 8

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)

Question 9

DIfferentiate REM sleep from sleep tremors?

Answer 9

Sleep tremors is a non -REM parasomnia - incomplete arousal and lack of recall of dream content

Question 10

Function of IL-8?

Answer 10

Chemokine produced by macrophages -> induce chemotaxis and phagocytosis in neutrophils

Question 11

HPV has a predilection for this type of surfaces?

Answer 11

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

Question 12

Procalcitonin is an acute phase reactant that elevate with ___ infections?

Answer 12

Bacterial (levels are low in viral infections)

Question 13

if a pts neutrophils fail to turn blue following exposure to nitroblue tetrazolium, what does this mean?

Answer 13

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

Question 14

Alcohol based disinfectants kill ___ viruses?

Answer 14

Enveloped ** it dissolves their outer lipid envelope.

Question 15

What can cause toxic shock syndrome?

Answer 15

Tampons or wound packing (allows for S. aureus to replicate locally and release pyrogenic toxic super antigens)

Question 16

Toxic shock syndrome toxin 1 (super antigens) bind to _____ complex of APC?

Answer 16

Super-antigens binds to MHC II w/o processing and non selectively activates T cells -> inflammatory cytokines -> dz manifestations

Question 17

Ganclyclovir adverse effect?

Answer 17

Neutropenina, anemia, and thrombocytopenina (also blocks host DNA polymerase)

Question 18

What organisms are resistant to cephalosporins?

Answer 18

Listeria, MRSA, Enterococci ( resistant PBPs)

Atypicals (Mycoplasma, Chlamydia) - no cell wall.

Question 19

The biofilm in S. epidermis is made up of?

Answer 19

extracellular polysaccharide matrix

Question 20

H. influenza ca grow when sheep blood is cross streak with S. aureus because?

Answer 20

B-hemolysis allows production of factors V (NAD+) and X.

Question 21

Pharyngeal is often present in people with impaired _____ immunity?

Answer 21

Cell-mediated (immunosuppresed)

Question 22

Inactivated (killed or component) viral vaccines generate a ___ response against viral antigens?

Answer 22

humoral response. Prevents viral entry into cells

** neutralizing Abs to hemagluttinin

Question 23

Live attenuated viral vaccines generate a _____ response?

Answer 23

Strong cell mediated immune response that kills virally infected cells + humoral immunity

Question 24

Aminoglycoside resistance is most commonly due to?

Answer 24

Antibiotic modifying enzymes (these enzymes add chemical groups to the antibiotic - diminishes ability to bind to 16S rRNA withing 30s ribosmal unit.)

Question 25

Suppurative (bacterial) parotitis cane present with elevated levels of?

Answer 25

Amylase (parotid gland secretes this)

**this condition occurs in elderly intubated and dehydrated (post -op) patients

Question 26

Suppurative parotitis is often caused by this bacteria?

Answer 26

S. aureus

Question 27

How does S. aureus become methicillin resistant?

Answer 27

acquisition of mobile genetic element that contains mecA gene -> codes for specialized PBP that have low affinity fro B-lactam antibiotics.

Question 28

Apart from hijacking the acting apparatus, what is listerias other virulence factors?

Answer 28

Listeriolysin O -> creates pores in phagosome memebrane -> allows for phagocytised bacteria to escape into the cytoplasm of monocytes and avoid lysosomal destruction.

Question 29

Explain phenotypic mixing?

Answer 29

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).

Question 30

Conversion from non toxigenic to toxigenic C diphteria occurs due to ?

Answer 30

infection with lysogenic bacteriophage - (cornephage beta) -> inserts tox gene -> expression of diphtheria AB toxin -> halts synthesis via ribosylation.