uWorld 52

Question 1

myocardial oxygen extraction exceeds that of any other tissue or organ in the body
due to high degree of oxygen extraction, increases in myocardial oxygen demand (doing exercise) are med by what

Answer 1

nearly proportionate increase in coronary blood flow

Question 2

the greatest difference in O2 content is between the aorta and what vessel in the body

Answer 2

coronary sinus (coronary venous blood is draining here)

Question 3

what distinguishes coronary circulation from the rest of the body

Answer 3

heart muscle is PERFUSED during DIASTOLE

myocardial O2 extraction is very high

myocardial oxygen demeaned and coronary blood flow are tightly coupled

Question 4

where do the PCL and ACL attache

Answer 4

PCL: ANTEROlateral surface of MEDIAL FEMORAL CODYLE and POSTERIOR part of intercondylar area of TIBIA

ACL: ANTERIOR portion of intercondylar area of TIBIA and the POSTEROmedial surface of the LATERAL FEMORAL CONDYLE

Question 5

whats the transverse genicularr ligament do

Answer 5

attaches the medial and lateral menisci anteriorly on the proximal articular surface

Question 6

what you see on fine needle aspiration of HASHIMOTO

Answer 6

mononuclear parenchymal infiltration (lymphocytes and plasma cells) with well-developed GERMINAL CENTERS

HURTHLE CELLS- large oxyphilic cells filled with granular cytoplasm- FOLLICULAR EPITHELIAL CELLS that have undergone MALIGNANT CHANGE

Question 7

what is the “triangle of treatment” for thyrotoxicosis aimed at minimizing

Answer 7

1. thyroid hormone synthesis and release
2. peripheral conversion of T4 to the more active T3 (inhibits iodothyronine doiodinase)
3. sympathetic outflow and/or its actions on target tissue

Question 8

beta-blockers are effective at treating what part of thyrotoxicosis

Answer 8

peripheral conversion of T4 to the more active T3

sympathetic outflow and/or its actions on target tissue

Question 9

what is akathisia

Answer 9

subjective restlessness with inability to sit still
days to weeks after starting antipsychotic treatment

inability to sit or stand in one position and may pace frequently or demonstrate other restless behaviors

Question 10

in most states minors can consent to what

Answer 10

PRENATAL CARE
diagnosis and treatment of STDs
CONTRACEPTION
DRUG or ALCOHOL REHABILITATION
emergency care

Question 11

what do you use to treat AGITATION and PSYCHOSIS associated with DELIRIUM

Answer 11

HALOPERIDOL (and other HIGH POTENCY first generation antipsychotics)
or some second-generation antipsychotics can be used (not clozapine though)

Question 12

what is doxepin

Answer 12

TCA

Question 13

what is an allosteric activator of the first step of gluconeogenesis

Answer 13

ACETYL-CoA (step is done by enzyme PYRUVATE CARBOXYLASE making oxaloacetate- BIOTIN dependent and occurs in mitochondria)

Question 14

ALKAPTONURIA is characterized by a deficiency in what conversion pathway

Answer 14

TYROINE to FUMARATE

dysfunctional HOMOGENTISATE OXIDASE (AR disorder)

Question 15

thoracodorsal nerve innervates what

Answer 15

LATISSIMUS DORSI- should extension, adduction, and internal rotation

Question 16

P-glycoprotein is what kind of protein

Answer 16

TRANSMEMBRANE patient that functions as an ATP-DEPENDANT efflux pump

broad specificity for HYDROPHOBIC compounds

human multi drug resistance (MDR1) gene

can reduce influx of drugs into the cytosol and increase efflux form the cytosol, thereby preventing the action of chemotherapeutic agents

Question 17

what are the pH, bicarb, and CO2 levels in ASPRIN OVERDOSE (4-5 hours after ingestion)

Answer 17

at this point most likely mixed RESPIRATORY ALKALOSIS (direct brain stimulation- happens FIRST) and ANION GAP METABOLIC ACIDOSIS
pH is actually close to normal (7.38) b/c of mixed respiratory alkalosis and metabolic acidosis

PaCO2 is hella LOW (20) b/c respiratory alkalosis

Plasma HCO3- is hella LOW (12) b/c of metabolic acidosis

Question 18

patients with adult-type coarctation of the aorta commonly die of what?

Answer 18

HYPERTENSION-ASSOCIATED complications:
left ventricular failure
rupture dissecting aortic aneurysm
intracranial hemorrhage

increased risk for ruptured intracranial aneurysm because of the increased incidence of congenital berry aneurysms of the circle of Willis as well as aortic arch hypertension

Question 19

people with ASD can get what problem

Answer 19

CHRONIC PULMONARY HYPERTENSION as a result of left-to-right intracardiac shunt

eisenmenger syndrome is the late-onset reversal of the shunt due to pulmonary vascular sclerosis

closer of the ASD can prevent this

Question 20

what is the immunochemistry seen with hydatiform moles

Answer 20

complete: p57 NEGATIVE
partial: p57 POSITIVE

Question 21

extremely high beta-hCG levels of a complete hydatifiform mole can cause what

Answer 21

HYPEREMESIS GRAVIDARUM
PRE-ECLAMPSIA
HYPERTHYROIDISM
THECA-LUTEIN CYSTS

fun facts: BUNCH OF GRAPES macroscopically and dont forget the “SNOWSTORM” appearance on ultrasound

Question 22

what is the ATTRIBUTABLE RISK PERCENT in the EXPOSED (ARPexposed)

Answer 22

important measure of the impact of a risk factor

represents the excess risk in an exposed population that can be explained by exposure to a particular risk factor

ARPexposed = 100*[(risk in exposed- risk in unexposed)/risk in exposed]

ARPexposed = 100* [RR-1)/RR]

Question 23

what is a COMPLETE ATRIOVENTRICULAR VANAL sepal defect

Answer 23

most common type of cardiac defect in patients with DOWN SYNDROME

failure of endocardial cushion fusion results in an OSTIUM PRIMUM ASD; a VSD; and a single, large COMMON AV VALVE

significant left-to-right shunting and AV valve regurgitation lead to excessive pulmonary blood flow and symptoms of HEART FAILURE

AV valve regard (HOLOCSTOLIC, heard best at APEX)
increased pulmonary venous return (MID-SYSTOLIC RUMBLE)

Question 24

what are the ADRs of nitrates

Answer 24

HEADACHES, CUTANEOUS FLUSHING, lightheadedness, HYPOTENSION, and REFLEX TACHYCARDIA

CONTRAINDICATED in hypertrophic cardiomyopathy , RV infraction , PDE inhibitors

Question 25

what is CEFEPIME

Answer 25

4th generation CEFALOSPORIN that CAN treat PSEUDOMONAS

Question 26

patients with acute viral hepatitis typically present how

Answer 26

FEVER, malaise, ANOREXIA, nausea/vomiting, RUQ pain choestatic symptoms after a week or so: jaundice, purpuritis, DARK-COLORED URINE and echoic stools (lacks bilirubin pigment)

Question 27

what is a functional heart murmur

Answer 27

due to hemodynamic changes, in the absence of any fixed vance lesions dilation of left ventricle in response to increased preload can result in functional mitral regurgitation, which can be eliminated by preload reduction and reduced by after load reduction

Question 28

what is the UBIQUITIN PROTEASOME PATHWAY (UPP) is essential for what

Answer 28

breakdown of intracellular proteins, both native and foreign, and helps recycle them into the amino acid building blocks ubiquitin functions as a tag that is attached to proteins to mark them for destruction process performed by UBIQUITIN LIGASES, enzymes that recognize specific protein substrates and catalyze ubiquitin attachment tagged proteins are then taken up by the proteasome, where they are broken down into their constituent oligopeptides and , eventually, amino acids

Question 29

what is the role of the ubiquitin proteasome pathway (UPP) in immune response

Answer 29

related to its ability to DEGRADE FOREIGN INTRACELLULAR PROTEINS, such as viral particles these proteins are degraded to an appropriate size, coupled to MHC CLASS I protein complex in the endoplasmic reticulum, and then presented on the cell surface for recognition by CYTOTOXIC CD8+ lymphocytes

Question 30

pericarditis 4 days after MI is due to what

Answer 30

pericardial inflammation OVERLYING the NECROTIC SEGMENT of MYOCARDIUM fibrinous or serofibrinous short lived and usually disappears with 1-3 days of aspiring therapy (fun fact: dressler syndrome is weeks to months after)

Question 31

what is seen in Dressler Syndrome

Answer 31

1 week to months after MI fever, pleuritis, leukocytosisi, pericardial friction rub, and chest radiograph evidence of new pericardial or pleural effusions autoimmune polyserositis provoked by antigens exposed or created by infarction of the cardiac muscle pericardium is usually DIFFUSELY INFLAMED other serial surfaces including the lung pleura may be involved generally responds to aspirin, NSAIDS, and/or glucocorticoids

Question 32

the infusion of glucose without thiamine in a patient with chronic thiamine deficiceny precipitates what

Answer 32

ENCEPHALOPATHY confusion, ataxia, and ophthalmoplegia from the triad of Wernicke encephalopathy hemorrhage into the maxillary bodies is characteristic

Question 33

what is an acer rod

Answer 33

AZUROPHILIC GRANULES found in cytoplasm of myeloblasts stain positively for MYELOPEROXIDASE

Question 34

what is seen in FANCONI ANEMIA

Answer 34

inherited cause of aplastic anemia present with SHORT STATURE and ABSENT THUMBS and is associated with an increased risk of malignancy (myelodysplastic syndrome, acute myeloid leukemia)

Question 35

what is myelodysplastic syndrome

Answer 35

caused by defect in stem cell maturation leading to ineffective differentiation of cell lines and, therefore, pancytopenia bone marrow biopsy will be hyper cellular with abnormally differentiated cells (misshapen nuclei) primarily occurs in patients over 65

Question 36

what is AXONAL REACTION

Answer 36

changes seen in neuronal body after the axon is severed cell body shows sings of CELLULAR EDEMA SWOLLEN and ROUNDED, with the NUCLEUS displaces to the PERIPHERY NISSL substance becomes FINE, GRANULAR and DISPERSED throughout the cytoplasm (central chromolysis) becomes visible 24-48 hours after the injury maximal changes in the neuronal body occurs approximately 12 days after the injury these changes reflect increased synthesis of protein by the cells in order to regenerate the severed axon

Question 37

what is Wallerian degeneration

Answer 37

occurs in the segment of axon that has lost connection with the cell body represents the degeneration of axon an dymelin distal to a point of injury fist: swelling and irregularity are noted in the distal segment of the axon within a week the axon is destroyed and its fragments are digested by Schwann cells and macrophages degeneration of the proximal segment extend to the closest node of Ranvier

Question 38

benzene causes what

Answer 38

aplastic anemia

Question 39

what is retinopathy of prematurity

Answer 39

use of concentrated oxygen therapy for neonatal respiratory distress syndrome may be complicated by abnormal RETINAL NEOVASCULARIZATION and is a major cause of blindness in developed nations thought to be VEGF reuptake mediated from return to regular air after temporary local hyperoxia in the retina

Question 40

what is terbutaline

Answer 40

a beta-mimetic tocolytic drug used to delay labor and delivery by suppressing uterine contractions use has been linked to an increased risk of neonatal intraventricalr hemorrhage, hypoglycemia, hypocalcemia, and ileus

Question 41

what are the complications of surfactant treatment

Answer 41

transient hypoxia and hypotension, blockage of an endotracheal tube, and pulmonary hemorrhage

Question 42

where do charcot-bouchard aneurysms occur

Answer 42

basal ganglia cerebellum thalamus pons intracerebral hemorrhage progressive neurologic deficits, headaches may follow

Question 43

what is the most common cause of lobar/cortical parenchymal hemorrhage

Answer 43

cerebral amyloid angiopathy

Question 44

what is hypertensive encephalopathy

Answer 44

PROGRESSIVE headache and nausea/vomitting followed by non localizing neurologic symptoms (confusion) patients deep intracranial hemorrhage makes hypertensive vasculopathy more likely

Question 45

what is hypoxic encephalopathy

Answer 45

caused by decrease oxygenation of the blood (due to cardiac arrest) often present with decreased consciousness (coma or vegetative state)

Question 46

what does squatting do in mitral valve prolapse

Answer 46

makes the murmur disappear (mid systolic click followed by late systolic murmur is MVP w/ mitral regurgitation- click is from sudden tensing of chord tendinae as they are pulled tight by leaflets)

Question 47

what is seen in the myxomatous lesions of MVP

Answer 47

proliferation of spongiosa of valve leaflets, fragmentation of elastin fibers with increase in mucopolysaccharide and type III collagen deposits

Question 48

what happens to murmur in hypertrophic cardiomyopathy when squatting

Answer 48

decreases in intensity (due to increase left ventricular volume and decreased outflow tract obstruction) systolic murmur at cardiac apex