UWorld_4.2 Flashcards
Calculation of absolute risk percent
- ARP = 100 * (risk in exposed - risk in unexposed)/risk in exposed
- ARP = 100 * (RR-1)/RR
Aging effects on aortic valve
- aging ==> cell death/necrosis ==> physiologic calcification in the setting of normal calcium levels
- aortic sclerosis = common in elderly adults
- can progress ==> calcified aortic stenosis = outflow obstruction
Glucagon receptor type + other hormones w/same receptor
- G-protein coupled receptor
- binding ==> activated Adenylate Cyclase ==> increased cAMP ==> activated PKA
- other hormones
- PTH
- B-andrenergic
- TSH
Aoritc regurgitation murmur
- early diastolic murmur
Nitrate adverse effects + prevention
- ==> reflex tachycardia due to relative hypotension
- prevented with beta-blockers
Metoprolol effects
- B1 selective blocker
- present @ heart & JGA
- ==> decreased HR
- ==> blocks renin release by JGA cells
Phenotypic mixing definition
- co-infection of cells with two viruses ==>
- next gen: one virus obtains nucleocapsid proteins from one virus and contains the genome of the other
- since no change in underlying genome ==> next gen of progeny revert back to original phenotype
Skin finding in Pseudomonas bacteremia
- ecthyma gangrenosum = cutaneous necrotic disease
- pseudomonas releases exotoxin ==> bv damage ==> ischemia & necrosis @ skin
Beta-thallesemia mutations ==>
- defective transcription, processing, or translation of b-globin mRNAs ==> deficiency in quantity/quality of b-globin genes needed to synthesize hemoglobin
Chediak-Higashi presentation
- defect in PMN lysosome fxn ==>
- neurologic defects
- nystagmus
- partial albinism
- due to abnormal melanin storage
- immunodeficiency
- recurrent pyogenic infections, usually staph or strep
Most common urea cycle defect
- defiency of Ornithine transcarbamoylase: ornithine + carbamoyl phosphate ==> citrulline in mitochondria
- ==> increased blood ammonium levels + increased urinary exrection of orotic acid
V2 effects @ medullary collecting duct
- ==> increased permeability to H20 and urea
Initial treatment of severe hypoglycemia
- in the field/@home:
- less severe (mild-moderate) ==> fast-acting carbs; e.g. fruit juice, glucose tablet
- unconscious: IM glucagon
- @ hospital: IV glucose
Tx for combined T-C and absence seizures
- valproic acid
Baroreceptor afferent nerve conduction
- Carotid baroreceptor info = CN IX (glossopharyngeal)
- Aortic baroreceptor info = CN X (vagus)
Net excretion calculation =
Net excretion (A) = (inulin CL)(plasma concentration(A)) - tubular reabsorption (A)
Winter’s formula + use
- PaCO2 = [1.5 * HCO3-] + 8 +/-2]
- if PaCO2 is greater than winter’s calculation = indication of inability to produce respiratory alkalosis to compensate for metabolic acidosis
Amphotericin B: SE
- Nephrotoxicity and electrolyte abnormalities
- ==> hypoK and hypoMG
- hypoK ==> T wave flat, ST-depression, U waves
Bethanacol: MOA
musc. antagonist
high vs. low selective proteinuria
- high = albumin & ferritin only (LMW)
- low = albumin + Ig + macroglob
Coll. synth defect in OI
- defect in procollagen peptidase ==> defect in C/N terminal protein cleavage
“Foamy” or “Frothy” urine ==> dx?
proteinuria or bile salts in urine
RCC clear cell lineage
proximal tubule cells
Calcinuerin fxn
- calc = protein phosphatase ==> dephosph NFAT ==> trxn factor for IL-2 ==> T cell growth and maturation
- Cyclosporine & Tacrolimus ==I calcineurin ==> anti-rejection/immunosuppress drugs
Unfractionated vs. LMWH
- unfractionated = binds ATIII and allows activity against factor Xa and thrombin (inactivation)
- LMWH ==> ATIII activity against Xa only
Parvovirus @ children vs. adults
- @ children: fever, malaise + erythema infectiosum = rash on cheeks; rahs may also be present extremities ==> trunk
- @ adults: arthritis in bilateral IP, metacarpal, knee and ankle joints
- resolves spontaneously (unlike RA)
Liver (unique) processing of triglycerides
- @ adipose tissue: lipase: triglycerides==> glycerol + FFA
- @ liver: glycerol kinase: glycerol ==> glycerol-3-P ==> DHAP ==> gluconeogen or glycosis
Lymph drainage to superficial inguinal lymph nodes
- all lower extremities, except calf
- umbilicus to feet w/external genitalia and anus
Insulin receptor mechanism
- insulin ==> tyrosine kinase ==> insulin receptor substrate phosphorylization ==> activation of protein phosphatase
- protein phosphatase ==> dephosph glycogen synthase = activated glycogen formation
- also ==> dephosph of fructose-1,6-bisphosphatase = inactive ==> inhibition of gluconeogenesis
Most abundant amino acid in collagen
glycine (at least every third)
Tongue innervation
- Motor = CN XII
- except palatoglossus m. = CN X
- Sensory
- Ant 2/3 = CN V3 (mandibular)
- Post 1/3 = CN IX
- Post. root/pharynx = CN X
- Taste
- Ant 2/3 = CN VII (chorda tympanii)
- Post 1/3 = CN IX
- Post. root/pharynx = CN X
Succinylcholine: MOA, use
- MOA: depolarizing NMJ blocker
- use: rapid induction/intubation or for surgical intubation
- phase I = augmented by AChEi (e.g. neostigmine)
- phase II = reversed by AChEi
