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Flashcards in #4 3/8 Deck (82)
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histology of true vocal folds

stratified squamous epithelium


- regions of respiratory tract with ciliated, pseudostratified, columnar, mucus-secreting epithelium
- regions with stratified squamous epithelium

- paranasal sinus, nasopharynx, most of larynx (including false cords), tracheobronchial tree
- oropharynx, laryngopharynx, anterior epiglottis, upper half of posterior epiglottis, true vocal cords


HIV fusion depends on...

(1) host cell CD4 + CCR5 and (2) HIV gp120


Nef and Tat HIV gene

Tat: role in viral replication
Nef: decreases expression of MHC class I on surface of expressed cells


When does tetrology of fallot present w/ cyanosis?

when pulmonic stenosis results in enough pulmonary HTN to turn VSD into a right-to-left shunt


Endocardiac cushion defects result in

defects in atrioventricular septum (left-to-right shunt, initially asymptomatic, but can have Eisenmenger syndrome later on


3 major cyanotic diseases caused by abnormal migration of neural crest cells...

tetralogy of fallot (anterior misalignment of aorticopulmonary septum), transposition of great vessels, truncus arteriosus


(3) mitochondrial myopathy (blotchy red muscle fibers on Gomori trichrome stain)

(1) myoclonic epilepsy w/ ragged red fibers [MERRF] (2) leber optic neuropathy [blindness] (3) mitochondrial encephalopathy w/ stroke-like episodes and lactic acidosis (MELAS)

ragged red bc abnormal mitochondria deposit under sarcolemma


Inheritance of cystic fibrosis

autosomal recessive (chr. 7)


fertility w/ cystic fibrosis

most men are infertile, but not sterile


human multidrug resistance (MDR1) gene

codes for P-glycoprotein, a transmembrane ATP-dependent efflux (esp good for hydrophobic agents like anthracyclines)

prevents influx as well as increases efflux


What precipitates sickling in HbS?

low oxygen, increased acidity, low volume (dehydration) [valine instead of glutamate at 6th AA position in beta subunit


hemoglobin M disease

mutation in heme binding pocket of alpha or beta chain; most common mutation replaces histidine in the heme binding pocket with tyrosine, results in the formation of an iron phenolate complex that resists the reduction of iron to the ferrous state --> methemoglobin


Wilson's disease

decreased ceruloplasmin


lipid loss in nephrotic syndrome under microscopy

polarized light -> oval fat bodies have maltese cross appearance


high altitude acclimatization process

inspired partial pressure (pO2) falls from 150 to 86mmHg, resulting from PaO2 of 60mmHg or less. hypoxemia stimulates carotid & aortic body chemoreceptors --> increased ventilatory drive --> hyperventilation and respiration alkalosis (increased pH, decreased CO2, low O2). drop in bicarb within 48 hours. within hours, increased EPO. see increased RBC 10-14 days. also, increased capillary density, myoglobin concentration, mitochondria


describe osteoclasts in paget's disease of the bone

very large, can have up to 100 nuclei (normal 2-5). will be tartrate-resistant acid phosphatase positive (like all osteoclasts)


factors important for osteoclastic differentiation

(1) M-CSF (macrophage colony-stimulating factor) and (2) RANK-L (receptor for activated nuclear factor kappa beta-ligand)


typical presentation of Paget's disease of bone

older gentleman, pain and deformity in a bony area and hearing loss (conductive problem w/ bone) . potentially caused by paramyxovirus infxn of osteoclasts


fibroblast growth factor on bone

increase bone formation, stimulate osteoblast. neurovascularization and wound healing


TGF-beta on bone formation

increases replication of osteoblast precursors and increased formation of mature osteoblasts. increase collagen synthesis. stimulate osteoclast apoptosis; decrease bone resorption


insulin-like growth factor on bone formation

IGF-1 increases osteoblast replication and collagen synth. decreases collagen degradation; inhibits MMP-13. anabolic


osteocalcin in bone formation

non-collagenous protein secreted by osteoblast. marker of bone formation. limits bone mineralization.


factors that stimulate osteoblasts



pulsus paradoxus (definition, detection, pathophysiology)

decrease in systolic BP greater than 10mmHg on inspiration. korotkoff sound first heard on expiration, then later on all phases of respiration.

caused by IMPAIRED expansion in PERICARDIAL space

normally, inspiration increases venous return --> increased volume of right heart, which expands into pericardial space.

when impaired expansion (acute cardiac tamponade, constrictive pericarditis, severe obstructive lung disease, restrictive cardiomyopathy)

here: increased RV volume pushes interventricular septum to left, reducing left heart diastolic volume & stroke volume --> decreases systolic BP.


Parvovirus B19

the only ss DNA virus (non-enveloped)


beta-hemolytic bacteria

s. aureus, listeria monocytogenes, s. pyogenes, s. agalactiae


listeria monocyogenes characterestics

- tumbling motility at 22 deg (immobile at 37)
- can multiply at 4 deg (refrigeration)
- only gram positive with LPS!


intracellular evasion strategies of Salmonella & Mycobacterium

- block fusion of phagolysosome with lysosome
- tuberculosis also blocks phagolysosome acidification


rheumatic fever on heart valves

almost always affects mitral, but both mitral and aortic are affected in some. often combined aortic stenosis and regurgitation, both --> increased LV diastolic pressure. predispose to infective endocarditis.