uworld 6?? Flashcards
type 1 collagen
dermis, bone, tendons, ligaments, dentin, cornea, blood vessels, scar tissue
type 2 collagen
cartilage, vitreous humor and nucleus pulposus
type 3 collagen
skin, lungs, intestines, blood vessels, bone marrow, lymphatics and granulation tissue!
type 4 collagen
basement membranes
how is calcium high in sarcoidosis?
T cells are active –> secrete gamma interferon which increases the activity of 1 alpha hydroxylase activity in macrophages–> converts 25 hydroxy vit D to 1, 25 hydroxy vit D.
where is 1 alpha hydroxylase normally found?
kidneys. macrophages have some too, but usually doesn’t do much unless have some chronic granulomatous thing when they’re super activated
what does ristocetin do?
activates gp1b receptors on platelets and makes them aailable for vWF binding
gingival bleeding, platelet count is normal, platelets aggregate normally to ADP but poorly to ristocetin. what is this?
vWF deficiency
what do you give for vWF deficiency? how does it work?
desmopressin. stimulates the release of vWF from endothelial cells. if super severe, then give blood products that have vWF…
mucocutaneous bleeding, incr bleeding time, platelet aggregation normal to ristocetin, decreased with ADP
Glanzmann thrombasthenia
what does glanzmann’s not have?
deficiency of GP2b/3a receptors
CYP 450 inducers
carbamazepine phenobarbital phenytoin rifampin griseofulvin
CYP 450 inhibitors
cimetidine ciprofloxacin erythromycin azole antifungals grapefruit juice isoniazid ritonavir (protease inhibitors)
neoplastic lymphocytes that have CD 19 and CD 5
mature B cell leukemia (eg. CLL or SLL)
red urine that darkens upon standing for 24 hours
Acute intermittent prophyria
mode of inheritance of acute intermittent prophyria?
autodom
what deficiency causes acute intermittent prophyria?
porphobilinogen deaminase deficiency
what is the nucleolus made of?
mainly rRNA–> mady by RNA pol 1
bilateral renal angiomyolipomas associated with what?
tuberous sclerosis. AD. cortical tubers and subendymal hamartomas in the brain. cardiac rhabdomyomas, facial angiofibromas, and ash leaf patches
cerebellar hemangioblastomas, retinal hemangiomas, and liver cysts are associated with what?
VHL dz. AD. at high risk for bilateral renal cell carcinomas!!
facial port wine stain and leptomeningeal capillary venous malformation is associated with what?
Sturge Weber syndrome. rare congenital vascular disorder
multiple telangiectasias on skin and mucosa–> typical presentation is recurrent epistaxis or GI bleeding (melena) is associated with what?
osler-rendu-weber syndrome or hereditary hemorrhagic telangiectasias
what cytokines are critical in granuloma formation?
IFN gamma, IL 12, TNF alpha.
macrophages release IL 12 to induce Th1 differentiation.
mature Th1s produce interferon gamma to activate macrophages and improve their ability to kill the ingested TB.
activated macrophages produce TNF alpha to recruit addnl monocytes and macrophages to the area.
what does IL 4 do?
promotes Th2 differentiation which stimulates B cells to isotype switch to IgE
what does C3a do?
stimulates mast cell histamine release –> vascular permeability and vasodilation
what does Leukotriene C4 do?
same as D4 adn E4 –> vasoconstriction, bronchoconstriction, and incr leukocyte adhesion to endothelium. (if sups low, then causes vasodilation and incr permeability of venules)
what does IL5 do?
growth and diff of b cells, eosinophils and isotype switch to IgA
where is the most common site of colonization of S aureus?
anterior nares…
where does all skin from the umbilicus down, including the anus (up to the dentate/pectinate line) but excluding the posterior calf drain to?
superficial inguinal lymph nodes.
where does the posterior calf drain?
popliteal lymph nodes
mutation for sickle cell
A-T in the betaglobin gene results in glutamate substituted by valine at position 6
what is homocysteine converted to?
methionine using BH4 and cobalamin
cysteine using B6 and serine
How is plasma glucose converted to sorbitol?
Aldose reductase.
Osmotic cellular injury => cataracts and peripheral neuropathy
alprazolam, triazolam, oxazepam are…?
short acting Benzos ( increased dependance, but decreased fall risk in elderly (shorter daytime drowsiness “hangover”
estazolam, lorazepam, emazepam are…?
medium Benzos (10-20 hours)
chlordiazepoxide, chlorazepate, diazepam, flurazepam are…?
Long acting Benzos (days) –> decreased risk of dependance but increased risk of fall in the elderly (longer daytime drowsiness “hangover”)
spherules containing endospores. presents as…?
Cocci!!
presents as: 1. acute pheumonia (most common) 2. chronic progressive pneumonia 3. pulmonary nodules and cavities 4. extrapulmonary nonmeningeal dz 5. meningitis (more severe for immunocompromised)
pigeon droppings. presents as…?
Crypto (yeast form)
pulm dz, meningoencephalitis in immunocomp.
bird and bat droppings in mississippi or ohio river basins
Histo!!!
what fungi are patients with asthma at risk for developing?
an allergic reaction to Aspergillus fumigatus called allergic bromchopulmonary aspertillosis.
symptoms: cough, dyspnea, wheezing, fever, migratory pulmonary infiltrates
how do penicillins and cephalosporins work?
irreversibly bind to penicillin binding proteins such as transpeptidases
glomerular sclerosis and hyalinosis most often seen when?
diabetic nephrosclerosis
hypoxemia causes what in the pulmonary vascular bed?
vasoconstriction!
hypoxic vasoconstriction occurs int eh small musculary pulm arteries to divert blood flow away from underventilated regions of the lung to more well ventilated areas
marfanoid hibitus, flesh colored nodules (mucosal neuromas), thyroid malignancy is what?
MEN 2B
parathyroid gland tumor, anterior pit tumor, and pancreatic timor is what?
MEN 1
parathyroid hyperplasia (not CA!), pheochromocytoma, medullary thyroid CA
MEN 2A
diarrhea, weight loss, and epigastric region calcification is a patient with chronic alcoholism is what?
chronic pancreatitis with resulting pancreatic exocrine insufficiency and malabsorption
most common benign liver tumor
cavernous hemangioma.
eggshell calcification of hilar nodes and birefringent particles surrounded by fibrous tissue
silica pneumoconioses
calcified pleural plaques and ferruginous bodies
asbestosis
noncaseating granulomas (and not sarcoidosis) in lung
berylliosis and hypersensitivity pneumonitis. but indistinguishable from sarcoidosis without the actual particles
perilymphatic accumulations of coal dust laden macrophages
coal miners lung
SUPS wide pulse pressure is caused by what?
aortic regurg
what are the absolute contraindications for OCP use? (6)
- prior thromboembolic event or stroke
- history of estrogen dependent tumor
- women over 35 who smoke heavily
- hypertriglyceridemia
- decompensated or active liver dz (would impair steroid metabolism)
- pregnancy
what is oral administration of D-xylose be used to differentiate?
between malabsorption of pancreatic vs. GI mucosa
if pancreas messed up, then monosaccharides should still be absorbed just fine.
tx for atypical depression or treatment resistant depression
MAOi (eg. phenelzine or tranylcypromine)
round or oval yeast with thick walls and broad based budding. lungs primary site, and skin and bone are major sites of dissemination
blasto!
only mold. septate hyphae that branch at 45 degree angles
Aspergillius!
small oval yeast with narrow based budding. pneumonia is rare!
Candida!!
round yeast with variable sizes and narrow based buds. thick polysaccharide capsule taht appears clear with india ink and stains raed with mucicarmine
Crypto
smaller yeast form and is found intracellularly within macrophages
Histo!
broad ribbonlike hyphae with rare septations
Rhizopus
retinal neovascularization. acute vision loss and metamorphopsia with funduscopy showing a gray-green subretinal membrane and maybe hemorrhage
wet age related macular degeneration. Tx is smoking cessation and VEGF inhibitor (eg. ranibizumab, bevacizumab)
gradual vision loss in one or both eyes and can cause difficulty driving or reading. chronic oxidative damage to retinal pigment epithelium and choriocapillaries. drusen deposites with pigment abnormalities
Dry age related macular degeneration
tx: antibodies against CD 20
(rituximab) on b cells. for various lymphomas and active rheumatoid arthritis
Tx: epidermal growth factor receptor inhibitors
(erlotinib, gefitinib) used to treat advanced nonsmall cell lung CA
tx: anti- IL 2 therapy
immunosurppression in organ transplant patients and in graft vs host
tx: inhibitors of tumor necrosis factor alpha
inflammatory autoimmune conditions. eg. rheumatoid arthritis, inflammatory bowel dz, and seronegative spondylarthropathies
what arteries run along the lesser curvature of the stomach?
left and right gastric. may be penetrated by ulcers and lead to hemorrhage
when a constant fraction of the drug is metabolized per unit time based on the serum concentration, it is said this drug has what order kinetics?
first order!
when a constant amount of drug is metabolizd per unit time, independant of concentration, it is said this drug as what order kinetics?
zero order!
what is found in raphe nuclei?
the only serotonin releasing neurons in the CNS. they go everywhere and synapse everywhere.
beta blocker and epi. what happens?
eliminates the beta effects of epi (vasodilation and tachy) and leaves the alpha effects (vasoconstriction)
medullary carcinoma of teh thyroid is characterized by what?
extracellular deposits of amyloid formed by calcitonin secreted from neoplastic parafollicular C cells
an aneurysm of what artery will cause compression of CN 3 and a 3rd nerve palsy?
it courses between the posterior cerebral and superior cerebellar arteries. an aneurysm in either will cause non pupil sparing 3rd nerve palsy = unilateral headache, eyepain, diplopia, dilated non reactive pupil, and ptosis of ipsi eye in a down an out position
measure renal plasma flow
= renal blood flow times (1-hematocrit)
disorganized cartilage, fibrous, and adipose tissue in the lung
hamartoma! –> peripherally located coin lesion” in 50-60 year olds. SUPS benign!
what do you see membrane splitting in (tram track)
alport and membranoproliferative GN
how is trypsinogen activated?
by duodenal eneropeptidases.
mysthenia gravis is associated with what?
thymus abnorm (thymoma, or thymic hyperplasia)
don’t have alpha galactosidase A. build up ceramide trihexoside
Fabry’s
don’t have B- glucosidase (glucocerebrosidase) and build up glucocerebroside
Gaucher
Don’t have sphingomyelinase. build up sphingomyelin
Neimann-pick
Don’t have hexoaminase a. Build up GM2 gangliosidase
Tay-sachs
Don’t have galactocerebrosidase. build up galactocerebroside, and psychosine
Krabbe
Don’t have arylsulfate A, build up cerebroside sulfate
Metachromatic leukodystrophy
why is there increased chololethiasis in pregnant women and those taking OCPs?
estrogen stimulated hypersecretion of cholesterol
and progesterone stimulated hypomotility of the gallbladder
why do you give topical vitamin D analogue for people with psoriasis?
analogue binds to the Vit D receptor and decreases keratinocyte proliferation and induces keratinocyte differentiation