3/1 UWORLD test # 28 Flashcards
Q 1. In mitral regurgitation murmur, what auscultation finding correlates with severity?
severity of MR = amount of blood flowing back to atrium
The more blood flowing back to the atrium, the more likely S3 sounds will present in subsequent diastole phase.
Q 1. Why INTENSITY of murmur does not correlate with severity?
larger regurgitant orifice leads to higher intensity sound.
This doesn’t necessarily correlates with amount of volume flowing back to atrium, thus doesn’t tell that much about severity
Q 1. What is S3 gallop? Its presence is normal for what patient group?
Rapid entrance of blood into ventricle during diastole
It correlates with amount of blood hanging out in atrium.
Severe MR/ HF can cause this.
- may be heard in children and young adults
Q 2. What is withdrawal symptoms of drug? How does it correlate with drug action
withdrawal symptom is the opposite action of drug
This makes sense: drug is acting on suppressing something, and as drug is removed, body’s compensation against that action will be intensified
Q 2. Withdrawal symptoms (5) of opioid (heroin)
- yawning
- lacrimation
- dilated pupil (remember opioid causes miosis)
- GI cramping/ diarrhea (remember opioid causes constipation)
- sweating
Q 2. Withdrawal symptoms (4) of alcohol? What is treatment?
- tremor
- sezuire
- delirium
- anxiety
Q 2. Withdrawal symptoms (3) of BDZ?
pretty similar as alcohol withdrwal
- insomnia
- tremor
- anxiety
Q 2. Withdrawal symptoms (4) of nicotine?
- irritability
- hypersomnia (excessive drowsiness)
- depression
- increased appetite
Q 3. Define linkage disequilibrium. example?
due to close proximity of two genes, allele frequency of two genes together is higher or lower than expected
- HLA-DQA1 and HLA-DQB1
Define incomplete penetrance. example?
not all individuals with mutant genotype develops phenotype
- BRCA1: not all mutants will develop breast cancer
Define pleiotropy. example?
mutation can cause multiple phenotypes
- PKU: musty body odor, intellectual disability, light skin
Define loss of heterozygosity. example?
with mutation of one allele, loss of complementary allele must be done to express phenotype
- retinoblastoma, and two hit hypothesis for lynch syndrome
Define dominant negative mutation. example?
mutation in one allele prevents normal gene function
- mutation of transcription factor in allosteric site. mutant can still bind to DNA, preventing wild-type transcription factor
Define locus heterogeneity. example?
mutation on different loci can cause similar phenotype
- albinism
Define allelic heterogeneity. example?
different mutations on same loci can produce same phenotype
- beta thalassemia
Define heteroplasmy. example?
presence of normal and mutated MITOCHONDRIAL DNA
Q 6. What does “anicteric infection” mean?
subclinical: infection with clinically insignificant symptoms
Q 7. What are three clinical features of nocardia?
- pneumonia (immunocompromised)
- brain abcess
- cutaneous symptom: cutaneous inflammation
Q 7. What may be seen in brain MRI with nocardia infection?
ring enhancing focal region
do NOT pick toxoplasmosis just because of this.
Toxo is protozoan. Question will give additional info
Q 8. Disaggregation of nuclear granules: is this reversible injury? or irreversible injury?
Reversible injury
do NOT confuse with nuclear fragmentation (karyorrhexis) or condensation (pyknosis)
Q 9. When does fetal hemoglobin is rapidly being replaced by adult hemoglobin? This explains delayed presentation of what diseases
- after 6 months
- gamma subunit in HbF is replaced by beta subunit in HbA. Thus, any defect with beta (beta-thalessmia or sickle cell)
Q 10. What is gross appearance of menigocele/mengiomyelocele?
cystic lesion in lower spine with hairy patch
Q 10. What intervention in mother can prevent neural tube defects?
folate supplementation
Q 13. What is motor endplate action potential? How does myasthenia gravis change it?
motor end-plate potential is the electric potential (NOT ACTION POTENTIAL) at the end of muscular junction.
In myasthenia gravis, motor end-plate potential is reduced due to less availability of functional ACh receptors. Thus, action potential is NOT generated
Action potential is generated as motor end-plate potential reaches threshold. Once it reaches threshold, same amplitude of action potential is generated, REGARDLESS of magnitude of motor end-plate potential
Q 13. What is excitation-contraction coupling?
Generation of action potential is linked to muscle contraction
excitation: action potential, contraction: muscle contraction
AP -> Ca2+ entry -> muscle contraction
Q 14. Scopolamine
- mechanism of action
- indication
- Ach receptor selective anti-muscarinic
- motion sickness
Q 15. Describe the molecular mechanism of insulin release in pancreatic beta-islet cells
glucose entry into pancreatic beta cell through GLUT2 (insulin-independent)
- > ATP generation via glycolysis within the cell
- > closure of ATP-SENSITIVE potassium channel
- > depolarization
- > voltage gated Ca2+ channel opening & Ca2+ entry
- > exocytosis of insulin granules (with C peptide)
Q 16. Schwannoma
- usually arises from which cranial nerve?
- intracranial mass occupies what location?
- due to this location, what other cranial nerves can be compressed?
- clinical presentations
- CN8
- cerebellopontine angle: between lateral pons and cerebellum
- mass may also compress CN7 and CN5
- UNILATERAL hearing loss: CN8
- asymmetric smile: CN7
- facial numbness: CN5
- lack of corneal reflex: CN5 & 7
Q 16. What neural disorder may present with BILATERAL hearing loss?
NF2 (neurofibromatosis type 2)
Q 19. Compare symptoms: radial nerve injury vs. low trunk branchial plexus injury
- radial nerve: wrist drop
- low trunk of branchial plexus: claw hands (interossi innervated by ulnar)
Q 20. Thrombosis induced ischemic injury in brain results in what type of necrosis? What is the mechanism of this type of necrosis?
Thrombosis -> ischemic injury -> release of lysozyme
-> liquefactive necrosis
CNS = fat rich = liquefactive necrosis
Q 20. Under what circumstance does hemorrhagic CNS infarct happen?
reperfusion injury
: introduce of oxygen radical
Q 20. Hemorrahgic infarct is common in what organ?
organs with dual supply: lung ( pulmonary artery + bronchial artery)
hemorrhagic infarct happens in brain during reperfusion. Most thrombotic infarct in CNS results in liquefactive necrosis
Q 22. Cholestyramine vs. ezetimibe
- mechanism of action
- changes in level of lipids
- side effects
- MOA
- cholestyramine: inhibit bile reuptake into liver
- ezetimibe: inhibit INTESTINAL cholesterol absorption - lipid changes
- cholestyramine: decreased LDL, increased in HDL & TG
=> cholestyramine is the ONLY drug that elevates TG
- ezetimibe: decreased LDL - side effects
- cholestryramine: GI upset
- ezetimibe: diarrhea, increased LFT
Q 23. Describe progression of cherry hemangioma
Grows rapidly and spontaneously regress by 5-8 yo
Q 25. What immune response causes autoimmune destruction of parietal cells in pernicious anemia?
CD4+ T cell
Q 26. Skin manifestation in Nisseria menigitis? what is the mechanism?
petechial rash due to thrombocytopenia
- sketchy: guy lying down the ground on pants with red dots
Q 28. What drugs (4) are proven to increase mortality in HF?
- ACEI
- ARB
- B blocker
- Spironlactone
Q 28. What is triamterene?
eNac blocker, same as amerolide
Q 29. staph allows co-growth of what bug? how?
H.influenzae
hemolysis by staph releases NAD+
Q 32. Latissimus dorsi
- innervated by what nerve
- which arm motion
- thoracodorsal nerve
- internal rotation: latissimus dorsi is attached to frontal side of humerus
Q 33. cervical adenopathy, gray pharyngeal exudate, myocarditis: what bug is this?
Diptheria
Q 34. What is energy metabolism in erythrocyte?
only glycolysis
there is no mitochondria in erythrocytes
Q 35. What would be a strategy for prevention of hepatocellular carcinoma in developing countries? why?
vaccination against HepB virus
There is high incidence in HepB infection in countries with hepatocellular carcinoma
Q 37. What neuroendocrine markers (3) may be seen in small cell lung carcinoma?
- neural cell adhesion molecule (NCAM, CD56)
- chromagranin A
- enolase
Q 38. Cromoyln
- mechanism of action
- indication
- stabilize mast cell and prevents degranulation
- prophlyaxis for seasonal symptoms, aspirin induced asthma, exercise induced asthma
