Flashcards in #4 3/8 Deck (82)
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
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
FGF, TGF-Beta, IGF-I
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.
the only ss DNA virus (non-enveloped)
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.
branched-chain alpha-ketoacid dehydrogenase, pyruvate dehydrogenase, and alpha-ketoglutarate dehydrogenase all require which five cofactors?
thiamine pyrophosphate, lipoate, coenzyme A, FAD, NAD (mnemonic: tender loving care for nancy)
describe path of pulmonary artery post bifucation (relative to aortic arch, SVC, left main bronchus)
pulmonary trunk is to the left of aortic arch. right pulmonary artery travels under aortic arch and posterior to SVC. left pulmonary artery travels superior over left main bronchus
at what costal cartilage level does SVC form
1st costal cartilage
presentation of complete hydatidiform mole
bunch of grapes, result of trophoblast proliferation. large villi with decrease villous blood vessels.
vaginal bleeding in first trimester
nausea and vomiting
excessive hcg -> theca-lutein cyst
prognosis of complete hydatidiform mole
most recover after removal. some progress to 1. invasive mole (penetrate uterine wall; hydropic villi and proliferated trophoblast) or 2. choriocarcinoma (malignancy of trophoblastic cells; atypical cyto and synctiotrophoblastc w/ focal hemorrhage and necrosis).
elevated AFP in pregnant woman suggests.. (4 things, 1 main)
fetal neural tube defect
underestimation of gestational age
abdominal wall defect
CEA is a marker for
formula for confidence interval
mean +/- 1.96*SD/sqrt n
SEM = SD/sqrt n
95% confident that the true mean of the underlying population falls in this interval (1 z-score)
mean, SD, z-score, sample size
examples of signals using receptor-tyrosine kinase
growth factor receptors: EGF, PDGF, FGF
examples of tyrosine-kinase ASSOCIATED receptors (JAK/STAT)
cytokines, growth hormone, prolactin, IL-2, colony-stimulating factors
ANP signaling receptor
intrinsic guanylate cyclase activity
what can arginine deficiency be confused with (clinical presentation)?
cerebral palsy, progressive spastic paresis. arginine deficiency -- build up of arginine, can't make urea and ornithine. rx: low arginine diet
synthesis of 5-HT
hydroxylation and decarboxylation of tryptophan by tryptophan hydroxylase
role of glutamate in the body
transports ammonia from peripheral tissues to kidney. in nephron, hydrolyzed by glutaminase to generate glutamate and free ammonium
orotic acid build up when
block in urea acid cycle; ornithine transcarbamylase deficiency (OTC), citrullinemia, and argininosuccinic aciduria
vitamin B6, B12, and folate deficiency are associated with high levels of what compound?
homocysteine --> associated with atherosclerosis and thrombotic events
formation of GABA
decarboxylation of glutamate by (GAD) glutamic acid decarboxylase
mature defense, where unacceptable drive/emotions redirected towards acceptable targets (rage -> gym)
vs. displacement, where redirected towards unacceptable targets (rage -> wall, pets)
immature defense, unacceptable feelings are ignored and opposite sentiment is adopted. (i.e. man is angry at wife, but instead compliments dress)
most impt virulence factor in e.coli UTI
Fimbriae, or pili (specifically P-fimbriae = pyelonephritis-associated pilli). permits adhesion
most impt virulence factor in e. coli meningitis
K1 capsulate antigen
component of lipopolysaccharide in enterobacter --> activation of macrophages, widespread release of IL-1, IL-6, TNF-alpha
outflow murmur with HCM
systolic anterior motion of mitral valve touches hypertrophied inter ventricular septum
inspiration effect on right and left heart
RIGHT: INCREASED venous return to right atrium --> increased volume in right ventricle. increase
LEFT: pulmonary vessel capacitance, DECREASING venous return to left ventricle
differentiate tricuspid regurg vs. mitral regurg vs. VSD
1. inspiration increases tricuspid intensity (MR and VSD don't)
- tricuspid loudest near left lower sternal border
- mitral loudest over cardiac apex (high pitched)
- VSD loudest over left sternal border bet 3/4th intercostal space
- aortic stenosis: midsystolic, crescendo-decrescendo, travels to clavicle
- mitral regurg: holosystolic, high-pitched, LLD, apex
- tricuspid regurg: inspiration increases intensity, left lower sternal border
- pulmonic stenosis
- VSD: holosystolic blowing murmur, left sternal border 3/4th intercostal space
- aortic regurg:
- mitral stenosis: mid-diastolic, low pitched murmur, starts after S2 and ends before S1
- tricuspid stenosis:
- pulmonic regurg: inspiration increases intensity early diastolic, starts w/ S2, ends before S1 (decrescendo), high-pitched blowing best heard over left 2nd and 3rd space
Tricyclic antidepressants receptor targets (5)
1. central and peripheral mAch-R
- tachycardia, delirium, dilated pupils, flushing, decreased diaphoresis, hyperthermia, intestinal ileus, urinary retention
2. peripheral alpha-1-adrenergic receptors
- peripheral vasodilation (orthostatic HTN)
3. cardiac fast Na+ channels
- conduction defects, arrythmia, hypotension
4. presynaptic NE 5HT ntx reuptake
seizure and tremors
5. histamine H1 receptor
most common cause of death in patients w/ antidepressant intoxication
what mediates cachexia?
TNF (along w/ sepsis)
death due to TCA toxicity results from.. Rx is..
primarily blockade of fast Na+ channels --> ventricular fibrillation and/or cardiogenic shock. Rx: fluid resuscitation w/ normal saline and hypertonic sodium bicarb
presentation of serotonin syndrome
hyperthermia, autonomic instability, muscle rigidity, myoclonus, diaphoresis
impairment of respiratory control centers in brainstem (ondine's curse)
decreased frequency and/or amplitude of involuntary respiratory result in respiratory arrest when sleeping. (voluntary breathing unaffected)
progressively weakening diaphragmatic contractions during ventilation w/ intact phrenic can be (2)
NMJ problem (myasthenia gravis) and/or abnormally rapid diaphragmatic muscle fatigue (restrictive lung / chest wall disease)
angiotensin II receptor blockers act on..
AT-1 (angiotensin II receptors); block constriction of vascular smooth muscle & block aldosterone secretion. also block negative feedback of renin, angiotensin I, angiotension II
alpha-1-adrenergic mediated vasoconstriction affects... (2)
skin and viscera (i.e. reduces renal and hepatic blood flow)
NE affects (2)
1. a1 -> vasoconstriction, increase systolic/diastolic BP
2. b1 -> increase cAMP. would imagine increase in contractility, conduction, and chronotropic effects, but counteracted by indirect baroreceptor-mediated reflex bradycardia (no change or even decrease)
what are some potential benefits of ACE inhibitors? when are ACE inhibitors contraindicated?
reduce mortality risk in patients w/ cardiovascular and peripheral vascular disease, decrease LV vol in aortic regurg, reduce infarct expansion & progressive LV remodeling post-infarct.
contraindicated in pts w/ extensive atherosclerotic disease & bilateral renal artery stenosis; ATII-mediated vasoconstriction of efferent arteriole is essential for GFR maintenance here
conus medullaris syndrome (vertebral level & clinical presentation)
L2 vertebral level; damage to cord; flaccid paralysis of bladder and rectum, impotence, and saddle (S3-S5) anesthesia (disk herniation, tumor, spinal fractures) can also have mild leg muscle weakness
cauda equina syndrome
results from massive rupture of an intervertebral disk capable of compressing 2+ (of the 18) spinal nerve roots. can be from any trauma/space occupying lesion.
involved in: sensory & motor of lower extremities, pelvic floor, sphincters
classic symptoms: low back pain radiating to one or both legs, saddle anesthesia, loss of anocutaneous reflex, bowel/bladder dysfunction (S3-S5), loss of ankle-jerk reflex with plantar flexion weakness of feet.
L3 L4, mediate quadriceps (knee-jerk/patellar reflex)
s1 and s2
when should you test serum cortisol for cushing?
evening, since cortisol should be low in most people (circadian rhythm) more sensitive and specific
gold standard diagnosis for mesothelioma & features that distinguish it from adenocarcinoma.
clinical presentation of mesothelioma?
EM; numerous slender microvilli w/ abundant tonofilaments
(as opposed to adenocarcinoma -- short, plump microvilli)
dyspnea and chest pain. hemorrhagic pleural effusion and pleural thickening
bronchoalveolar carcinoma on chest x-ray
variant of adenoarcinoma in periphery of lung. peripheral mass or area of pneumonia-like consolidation
distinguish small cell and squamous carcinoma (2 similarities, 1 distinguish) on X-ray and staining
1. both arise form major bronchi 2. both will appear as hilar mass 3. small cell stains for neuroendocrine markers like chromogranin and synpatophysin, squamous stains for keratin and intercellular bridges.
how do thiazides cause hypokalemia (2 mechanisms?) hyperglycemia? hyperuricemia? hypercalcemia?
hypokalemia: 1. increased delivery of Na+ to CT 2. volume contraction stimulates aldosterone secretion, which increases K+ excretion
--> leads to muscle weakness & ECG problems
hyperglycemia: decreased insulin secretion & glucose uptake by tissues
hyperuricemia: hypovolemia increases uric acid reabsorption in PCT
hypercalcemia: increase calcium reabsorption
Rx: idiopathic hypercalciuria / recurrent calcium stone nephrolithiasis
thiazide diuretics; increase Ca++ reabsorption in DCT
clinical presentation with hyperphosphatemia?
like hypokalemia: muscle weakness and paralysis. commonly seen in alcoholics
renal blood flow formula
RBF = (PAH clearance / 1- hct)