Random Flashcards
AE of sildenafil (PDE5 inhibitor)
can inhibit PDE6 in the retina (color vision) –> bluish discoloration of vision
non-arteritic anterior ischemic optic neuropathy (sudden monocular vision loss)
how do PDE5 inhibitors improve erectile dysfunction
nitric oxide –> induces formation of cGMP –> vascular smooth muscle relaxation –> end of erection
PDE5 inactivates cGMP (maintains erection)
examples of PDE5 inhibitors
sildenafil, vardenafil, tadalafil, avanafil
indications for PDE-5 inhibitors
erectile dysfunction
pulmonary hypertension
BPH (tadalafil only)
cause of vasospastic (prinzmetal) angina
endothelial dysfunction and autonomic imbalance that lead to intermittent coronary vasospasm and myocardial ischemia
compare primary ciliary dyskinesia and cystic fibrosis
both have chronic rhinosinusitis and nasal polyposis due to impaired mucociliary clearance
failure to thrive and weight loss are NOT associated with primary ciliary dyskinesia
demographic most likely to get uterine fibroids
African american women
symptoms of uterine fibroids
- heavy menses
- pressure symptoms (pelvic pain, constipation, urinary frequency)
- impaired fertility
- enlarged, irregular uterus
what is the mechanism of radiation induced lung injury
affects alveolar-capillary barrier formed by alveolar epithelial cells and vascular endothelial cells
acutely –> impaired gas exchange and hyaline membrane formation
chronically –> fibrosis (TGF-B)
“double bubble” sign on x-ray indicates
duodenal atresia
thin, curvilinear areas of lucency that parallels the bowel wall lumen in an infant indicate what
pneumatosis intestinalis (air in the bowel wall)
can be caused by necrotizing enterocolitis
layers to get through in a cricothyotomy
1) skin
2) superficial cervical fascia (including subcutaneous fat and platysma muscle)
3) pretracheal layers of deep cervical fascia
4) cricothyroid membrane
MOA metronidazole
forms toxic free radical metabolites in bacterial cell that damage DNA
MOA fidaxomicin
macrocyclic antibiotic that inhibits sigma subunit of RNA polymerase, leading to protein synthesis impairment and cell death
indications fidaxomicin
c. diff infections
antibiotics indicated in c. diff infections
oral vancomycin, metronidazole, fidaxomicin
why do 25% of active TB patients have a false negative skin test
impaired lymphocytic response
how does fibroblast growth factor 23 help regulate phosphate levels
it is secreted by osteocytes in response to hyperphosphatemia and binds to FGF23 receptor –> suppresses 1-hydroxylase (converts vitamin D to active form) –> decreases intestinal phosphate absorption and decreases renal phosphate reabsorption
why does diverticulosis cause hematochezia
diverticula tend to form in areas where intraluminal colon wall lacks structural integrity, which is normally located where the vasa recta are –> weakened vessels can ulcerate and rupture
treatment for juvenile myoclonic epilepsy
broad spectrum anticonvulsant (valproic acid, levetiracetam)
clozapine MOA
second generation anti-psychotic
what is the only medication that has consistently shown superior efficacy in treatment-resistance schizophrenia
clozapine
most often cause of death in ALS patients
respiratory failure
decreased vital capacity
inheritance of G6PD deficiency
x-linked recessive
hemolytic anemia due to medication induce oxidative stress indicates what dz
G6PD deficiency
BMI CUT OFF FOR ANOREXIA
18.5 NOT 17.5
pathophysiology of MVP
myxomatous degeneration (pathologic deterioration of the connective tissue) affecting mitral valve leaflets and chordae tendinae
enzyme deficient in classic galactosemia
galactose-1-phosphate uridyltransferase
galactose-1-phosphate –> glucose-1-phosphate
most common manifestation in mild galactosemia
cataracts (due to galactitol)
how does amyl nitrite work in cyanide poisoning
it oxidizes Fe2+ to Fe3+ which generates methemoglobin
methemoglobin has high affinity for cyanide, so it binds and sequesters cyanide in the blood
describe schizotypical personality disorder
magical thinking (superstitiousness, clairvoyance) and odd perceptual disturbances that are SUB-threshold for a psychotic disorder
they DO NOT experience persistent, fixed delusions or frank hallucinations seen in schizophrenia
they rarely sustain close relationships due to excessive social anxiety
describe schizoaffective disorder
shares symptoms with schizophrenia and mood disorders
> 2 weeks of psychotic symptoms without manic or depressive episode
burkoholderia cepacia:
- gram stain?
- catalase +?
- lactose fermenting?
- gram negative
- catalase positive
- non-lactose fermenting
is bordetella pertussis catalase positive?
yep
is serrate catalase positive?
yep
is pseudomonas catalase positive
yep
how does systemic vascular resistance and pulmonary vascular resistance change during pregnancy
both decrease due to vasodilatory mechanisms that occur during pregnancy
where do spinal nerves exit in the lumbar spine
BELOW the vertebral level
L5 nerve root exits below L5 vertebrae
why do patients need a nitrate-free interval every day when taking nitrates
to decrease tolerance
around the clock nitrate administration rapidly results in development of tolerance to nitrates
how does age change prognosis in PSGN
increased age worsens prognosis
compare effects of raloxifene and tamoxifen
raloxifene:
agonist on bone, antagonist on breast and uterus (no increased risk for breast or uterine cancer)
tamoxifen:
agonist on bone, antagonist on breast, agonist on uterus (increases risk of endometrial hyperplasia/cancer)
what antibodies exist in grave’s disease
thyrotrophic (TSH) receptor antibodies
what antibodies exist in hashimoto thyroiditis
thyroid peroxidase antibodies
pathogenesis of hemochromatosis
mutations in HFE protein
HFE protein normally interacts with transferrin receptor to form complex that functions as a sensor of iron stores
HFE mutation –> enterocytes and hepatocytes detect falsely low iron levels –> accumulation of iron
brain tumor in the ventricles int most likely a
ependymoma
symptoms of IgA nephropathy
painless hematuria within 5-7 days of a URI
compare IgA nephropathy and hence schonlein purpura
IgA nephropathy: painless hematuria within 5-7 days of a URI
HSP: IgA nephropathy with extra renal symptoms (abd pain, arthralgia, purport)
pathogenesis of neuronal injury in DM
nonenzymatic glycosylation of tissue proteins resulting in hyalinization of endometrial arterioles –> narrowing of arteriole lumen –> ischemic nerve damage
also
intracellular hyperglycemia in peripheral nerves –> increased metabolism of glucose into sorbitol by aldose reductase –> accumulation of sorbitol –> oxidative stress in the nerve
