UWorld Exam 1 Section 1 Flashcards
What is the clinical presentation of ARDS?
Hypoxemia and cyanosis in the absence of heart failure
White-out on chest x-ray
What is the cause of ARDS (pathophysiology)?
Injury and inflammation of alveolar pneumocytes and pulmonary epithelium
Inflammatory insult leads to recruitment of neutrophils which release mediators (e.g. proteases and free radicals) that cause futher damage
Leads to increased pulmonary capillary permeability (fluid entering alveoli), diminished surfactant production (alveolar collapse), leakage of protein-rich fluid and necrotic debris (hyaline membrane formation)
List cardiac tissue in order from fastest so slowest conduction velocity
Purkinje system
Atrial muscle
Ventricular muscle
AV node
Where is the SA node located?
On the R atrial wall near the SVC
Where is the AV node located?
Interatrial septum near the tricuspid orifice
Paget disease of the bone is associated with which bone tumor?
Osteosarcoma
What 4 bony diseases does renal osteodystrophy encompass?
Hyperparathyroid bone disease
Osteomalacia
Mixed uremic osteodystrophy
Aplastic bone
Describe the defect in globus sensation
Globus senstaion is a FUNCTIONAL disorder of the esophagus, not due to a structural abnormality
Abnormal sensation of tightness, foreign body, or fullness in the throat
Often worsened with swallowing saliva and alleviated with food or liquid
What is the triad in Plummer-Vinson syndrome
Plumbers DIE
D - dysphagia (glossitis)
I - Iron deficiency anemia
E - esophageal web
What is the immune response in gout
Bare urate crystals are shed and exposed to IgG antibodies which leads to neutrophil phagocytosis and release of inflammatory cytokine (primarily IL-1)
How does Oseltamivir (Tamiflu) work?
It inhibits neuraminidases (NA) in Influenza virus so that virus particles remain attaches through hemagglutinin binding of sialic acid, and thus new virions cannot be released from infected cell
What is DNA laddering and cellular function is it an indicator of
DNA laddering is the appearance of DNA fragments in multiples of 180 base pairs
This is a sensitive indicators of apoptosis
Lymphoid malignancies (e.g. follicular B cell lymphoma) often evade programmed cell death by overexpressing BCL2, an antiapoptotic protein
What is achondroplasia?
Failure of longitudinal bond growth, leading to short limbs
Constitutive activation of fibroblast growth factor receptor (FGFR3) actually inhibits chondrocyte proliferation
What is the definition of mosaicism, somatic mosaicism, and germline mosaicism
Mosaicism - presence of multiple genetically different cell lines within the body (typically results from mutation during early stages of embryonic development)
Germline mosaicism - involves only oocytes or spermatocytes (should be considered in genetic mutation in offspring but not parents)
Somatic mosaicism - mutation in somatic cells (cannot be passed to offspring)
Describe the definitino of penetrance
Probability that a person with a given mutant genotype will exhibit the corresponding phenotype
What is pleiotropy?
Occurrence of multiple, seeming unrelated phenotypic manifestations, often in different organ systems, as a result of a single genetic defect
What disease is associated with Auer rods and what is the associated translocation
Acute myeloid leukemia (especially APL)
APL = t(15;17)
Think: Auer sounds like Furer (Hitler) - I am 16 going on 17 (15;17)
What is the treatment for Acute Promyelocytic Leukemia?
all-trans retinoic acid
Becuase the mutation is a translocation of retinoic acid receptor t(15;17)
What translocation is associate with B-ALL
t(12;21)
t(9;22)
What 2 things to integrins bind together?
Attaches cell to basement membrane
Hemidesmosomes within epithelial cells rely in integrins to bind the epithelial cell to fibronectin and laminin within the extracellular membrane
What is the histologic presentation of molluscum contagiosum
Cytoplasmic inclusion bodies (“molluscum bodies”) within keratinocytes
Describe the histologic appearance of basal cell carcinoma
Basaloid cells with peripheral palisading nuclei (cells lined up along periphery of basal cell nodules)
Describe the histologic appearance of Verruca vulgaris
Common warts caused by HPV
Will have koilocytes (enlarged nuclei with cytoplasmic vacuolization - perinuclear halos)
Defect in what muscle would lead to inability to raise arm over the head and protrustion (“winging”) of the medial border of the scapula when the outstretch arm is pushed forward against resistance
Serratus anterior
Originates on the frist 8 ribs and inserts on the medial border of the scapula
What movement is levator scapulae responsible for?
And what is its innervation
Elevation of the scapula and rotation of the glenoid fossa (shoulder joint) inferiorly
Innervated by 3rd and 4th cervical spinal nerves and dorsal scapular nerve
What movement is pectoralis minor responsible for and what nerve is it innervated by?
Draws the scapula anteriorly and inferiorly
Originates from the anterior surface of 3-5 ribs and attaches to the coracoid process of the scapula
Innervated by the medial pectoral nerve
What movement is the trapezius muscle responsible for and what nerve is it innervated by?
Elevation and retraction of the scapula
Also acts with the serratus anterior to rotate the glenoid fossa (shoulder joint) superiorly
Innervated by the spinal accessory nerve (CN XI)
What nerve innervates the serratus anterior?
Long thoracic nerve
May be injured with trauma or surgery near the lateral chest wall
Leads to scapular “winging” and inability to raise arm over head
