uWorld 40

Question 1

what can you use to treat PSORIASIS that ACTIVATES and NUCLEAR TRANSCRIPTION FACTOR

Answer 1

CALCIPOTRIENE aka calcipotriol (calcitriol, tacalcitol)- topical vitamin D analog that bind s to and activates the vitamin D receptor, a NUCLEAR TRANSCRIPTION FACTOR that causes inhibition of keratinocyte proliferation and stimulation of keratinocyte differentiation
also shown to inhibit T cell prolieraftoin and other inflammatory mediators

Question 2

what is ustekinumab (stelara)

Answer 2

human monoclonal antibody used in PSORIASIS the targets IL-12 and IL-23

it INHIBITS DIFFERENTIATION and ACTIVATION of CD4+ Th1 and Th17 cells

Question 3

acute hemolytic transfusion reaction is caused by what

Answer 3

TYPE II HYPERSENSITIVITY (ANTIBODY MEIDATED)

anti-ABO usually IgM in the recipient bind the corresponding antigens on transfused donor erythrocytes, leading to COMPLEMENT ACTIVATION

ANAPHLATOXINS (C3a and C5a) causes vasodilation and symptoms of shock, while formation of MAC leads to COMPLEMENT-MEDIATED CELL LYSIS

fever, HYPOTENSION, CHEST and BACK PAIN, HEMOGLOBINURIA

Question 4

what doe the different RNA pols make

Answer 4

RNA pol I: rRNA

RNA pol II: mRNA

RNA pol III; tRNA

MADE IN ORDER THEY ARE NEEDED TO MAKE SHIT

Question 5

what is the toxin found in poison mushrooms

Answer 5

AMATOXINS (AMANITA PHALLOIDES) aka DEATH CAP

bind to RNA POLYMERASE II and halt mRNA synthesis, ultimately resulting in APOPTOSIS

really fucked up the liver, GI, and proximal convoluted renal tubules

6-24 hours after ingestion get abdominal pain, vomiting, and severe cholera-like diarrhea that may contain blood and mucus

acute hepatic and renal failure in severe poisoning

Question 6

how does RICIN (Ricans communis) work

Answer 6

inhibits PROTEIN SYNTHESIS by cleaving the rRNA component of the eukaryotic 60S subunit

Question 7

diagnosis of cellulitis from a gram positive thing in clusters, the organism synthesizes what protein that is part of peptidoglycan cell wall and what does it do

Answer 7

STAPH AUREUS

PROTEIN A

binds Fc portion of IgG resulting in decreased production of C3b, leading to impaired opsonization and phagocytosis

Question 8

what pulmonary defense mechanism clears the respiratory tract of deposited particles less than 2 micrometers in size

Answer 8

PHAGOCYTOSIS

particels 2.5-10 micormeters in size ever the trachea and crunch and are cleared by the mucociliary transport

Question 9

coughing, sneezing, and upper respiratory trapping are the mechanisms for clearing what sized particles

Answer 9

the largest

Question 10

what are the signs/symptoms of ankylosing spondylitis

Answer 10

low back pain (onset less than 40, insidious onset, improves with exercise but not with rest, PAIN at NIGHT)

hip and buttock pain

LIMITED CHEST EXPANSION and SPINAL MOBILITY (HYPOVENTILATION)

ENTHESITIS (inflammation at the site of INSERTION of a TENDON to the bone)

systemic systems (fever, chills, fatigue, weight loss)

acute ANTERIOR UVEITIS (unilateral pain, photophobia, blurry vision)

ASCENDING AORTITIS which can lead to dilation of aortic ring and aortic insufficiency

Question 11

sudden onset of DYSPNEA in the setting of CALF SWELLING is strongly suggestive of what

Answer 11

PULMONARY EMBOLISM

V/Q MISMATCH causing significant INTRAPULMONARY RIGHT-to-LEFT SHUNTING causing HYPOXIA

HYPERVENTIALION

Question 12

structured handoffs that include specified key elements (a systematic procedure for sign-out, checklists of tasks that need to be completed, a standardized approach for each patient) have been shown to significantly reduce what

Answer 12

PREVENTABLE ADVERSE EFFECTS

Question 13

what vitamin can be used to treat measles

Answer 13

VITAMINE A

dont forget about subacute sclerosis pan encephalitis years after the measles

Question 14

vasopressin activates decreased the renal clearance of what

Answer 14

UREA

activates UREA TRANSPORTERS in the MEDULLARY COLLECTING DUCT, increasing urea reabsorption

passive absorption of urea in medullary collecting interstitial in the presence of ADH significantly increases the medullary osmotic gradient, allowing the production of maximally concentrated urine

Question 15

brown pigment stones typically arise secondary to bacterial E. coli) or helminthic (Ascaris lumbricoides, Clonarchis sinensis) infection of the BILIARY TRACT, which results in relate of what

Answer 15

BETA-GLUCURONIDASE by injured hepatocytes and bacteria

this enzyme hydrolysis bilirubin glucoronides and increases the amount of unconjugated bilirubin

Question 16

what kind of stones are seen in chronic hemolytic anemia

Answer 16

pigment gallstones (form the unconjugated bilirubin)

Question 17

what does 7-alpha-hydroxylase do

Answer 17

catalyzes conversion of cholesterol to 7-alpha-hydroxycholesterol (first step in BILE ACID SYNTHESIS)

net effect of this enzyme is to lower the cholesterol to bile acid ratio and lower risk of cholesterol stones

Question 18

what are pigment stones

Answer 18

made up of CALCIUM and UNCONJUGATED BILIRUBIN and typically arise secondary to bacterial or helminthic infection of biliary tract

beta-glucoronidcdase related hydrolyzes the bilirubin glucornides to unconjugated bilirubin

Question 19

what is tetrodotoxin

Answer 19

pufferfish poisoning

neurotoxin produced by microorganisms associated with the fish

binds VOLTAGE-GATED SOIDUM CHANNELS in NERVE and CARDIAC tissues, preventing sodium influx and depolarizaiton

Question 20

what is the most important risk factor for development of intimal tears leading to AORTIC DISSECTION

Answer 20

HYPERTENSION

Question 21

Burger disease (thromboangiitis obliterans) is what

Answer 21

vasculitis in SMOKERS that affected medium and small arteries but mainly TIBIAL and RADIAL nerves

Question 22

what causes eversion of the food

Answer 22

SUPERFICIAL PERONEAL NERVE (via PERONEUS LONGUS and BREVIS)

also does sensory over lateral leg and dorsolateral foot

Question 23

what is seen in COMMON PERONEAL NERVE INJURY

Answer 23

susceptible at the LATERAL NECK of the FIBULA caused by COMPRESSIOn (prolonged lying during surgery, crossing the legs, leg casts) or PROXIMAL FIBULAR FRACTURE

“FOOT DROP” from deep peroneal (innervation of anterior compartment muscles responsible for ankle dorsiflexion via TIBIALIS ANTERIOR and toe extension via extensor digitorum longs, extensor hallucis longus)

superficial peroneal nerve involvement causes impaired foot EVERSION (peroneus longs and brevis) and sensory loss over the lateral leg and dorsolateral foot

Question 24

femoral nerve injury results in what

Answer 24

weakness on hip flexion and knee extension due to iliopsoas and quad involvement

medial leg and anteromedial thigh sensory fucked

Question 25

what does the sciatic nerve do

Answer 25

leg flexion at the knee and also supplies TIBIAL AND PERONEAL NERVES so everything they do

sensory the the entire foot via dural and postural tibial nerve and posterolateral leg

Question 26

maple syrup urine disease is treated how

Answer 26

avoid Ilosleucine, leucine, and valine (branched chain amino acids)

SUPPLEMENT with THIAMINE (B1)

“I Love Vermont maple trees w/ B1ranches”

why B1? uhhh alpha-keto DEHYDROGENASE is fucked bruhh these dehydrogenase things need B1 (pyruvate dehydrogenase complex does to nigga)

Question 27

what is the most common valve affected by infective endocarditis, what is the most common underlying valvular disease predisposing this valve to development of infective endocarditis

Answer 27

MITRAL VALVE

MITRAL VALVE PROLAPSE (with or without regurgitation)

check for DENTAL EXTRACTION or PROCEDURE in question stem

also valvular sclerosis, mechanical valves, and rheumatic heart disease are important predisposing factors just not as important as MVP

Question 28

what congenital heart lesions predispose to infective endocardiitis

Answer 28

bicuspid aortic valve
ventricular septal defects
patent ductus arterioles
unreported tetralogy of Fallot

Question 29

what is a frequent cause of infective endocarditis in developing countries

Answer 29

rheumatic heart disease

Question 30

what are some findings of NF1

Answer 30

PSEUDOARTHROSIS
CAFE-au-LAIT spots
neurofibromas
lisch nodules (asymptomatic hamartoma of the iris)
optic nerve gliomas 
SPHENOID DYSPLASIA
SCOLIOSIS
meningiomas
astrocytomas
gliomas
pheochromocytoma

Question 31

trabecular thinning with fewer interconnections is seen in what

Answer 31

osteoporosis (primarily in trabecular, aka spongy, bone)

Question 32

increased deposition of unmineralized osteoid is very characteristic of what

Answer 32

vitamin D deficiency

Question 33

histologically, osteoporosis is characterized by what

Answer 33

persistence of primary, unmineralized SPONGIOSA in the medullary canals

(in normal peeps, the primary spongiosa is replaced by bone marrow)

Question 34

aortic dissection is initiated by what

Answer 34

TEAR in the AORTIC INTIMA

Question 35

where is the psoas muscle located

Answer 35

anterior surface of transverse processes and lateral surface of there vertebral bodies at T12-L5

acts in FLEXION of thigh at HIP and also contributes somewhat to lateral rotation and abduction of the thigh

inferior (at around the level of the inferior ligament), the psoas muscle combines with the iliac muscle to form the ILIOPSOAS mSUCLE, which function in hip flexion

Question 36

what are risk factors for primary psoas abscess development

Answer 36

HIV
IV drug use
diabetes