Question Log Flashcards
Acute onset CVP elevation, together with HOTN and tachycardia, can occur with what conditions?
cardiac tamponade or tension pneumothorax
Acute onset HF following viral illness should make you think?
dilated cardiomyopathy caused by viral myocarditis, which manifests as LV/RV dilation, mitral/tricuspid regurg, inc. ESV/EDV in LV
*unless there’s a high systolic pressure gradient between LV and aorta, because then that suggests LV outflow obstruction
Acute transplant rejection time frame and histopathology
1-4wks post-transplant; dense lymphocytic infiltrate in the interstitium of the organ
Aldolase B is part of what pathway?
Fructose (and Sucrose which can become fructose); Fructose to F-1-P is by Fructokinase, then F-1-P to Glyceraldehyde or DHAP is by Aldolase B
Alveolar transmural pressure and Intrapleural pressure
ATP is always positive; at FRC the airway pressure is 0 and there’s no force for bringing air in or out; at FRC the chest wall tendency to open and the lung tendency to collapse results in intrapleural pressure being about -5 cmH2O
Anti-Smith Ab - what does the Smith protein do?
Ab associated with SLE; the Smith protein complexes with snRNA to form a spliceosome, which cuts out introns from mRNA before it leaves the nucleus
Aortic stenosis, Afib, and Pulmonary edema
AS –> LVH –> dependent on atrial strength to fill up LV
Afib –> less likely to fully fill LV –> blood backs up into lungs –> pulmonary edema
Bilirubin metabolism pathway
Heme –[Heme Oxygenase]–> Biliverdin (green) –[Biliverdin reductase]–> Unconj Bilirubin –[Glucoronyl transferase]–> Conj bilirubin (liver) –[bacterial dehydrogenase]–> Urobilinogen (gut) –> Stercobilin –> brown color to feces
Bleeding from the nipple, think -
intraductal papilloma
Calculating resistance in parallel circuits
1/Rt = 1/R1 + 1/R2 + … 1/Rn
Can histamine antagonists be used in asthma?
Histamine antagonists are ineffective in asthma
Causes of dilated cardiomyopathy
Coxsackie B viral myocarditis, peripartum, alcoholism, thiamine def/wet beriberi, cardiotoxic drugs, chronic SVT
Causes of polyhydramnios
“decreased swallowing: esophageal/duodenal obstruction, intestinal atresia, or anencephaly
increased fetal CO: fetomaternal hemorrhage, Parvo infxn, alloimmunization”
CCBs’ effect on pacemaker cells vs. cardiac myoctes
“PM cells: will decrease/slow the Ca channel opening and thus Ca deolarization; this decreases the rate of firing of the SA and AV nodes
Myocytes: will decrease the opening of Ca channels, decrease the IC [Ca], and thereby reduced the excitation-contraction coupling”
Cells of bronchial epithelium
distal to terminal bronchioles = MPs; proximal is all lined with ciliated epithelium
Characteristics of mesothelioma
epithelioid neoplasm of the serosa, joined by desmosomes and have abundant tonofilaments with long slender microvilli; hemorrhagic pleural effusions are frequent and on CXR will see nodular or smooth pleural thickening
Cherry-red macula - ddx?
Hyphenated: Niemann-Pick (HSM; foam cells) and Tay-Sachs (tay-six; NO HSM; onion skin lysosome)
Clinical Triad: acute neuro abnormalities, hypoxia, and petechial rash on chest (following long bone fracture/surgery)
fat embolism to lungs
Common cause of pigmented stones
excretion of large amounts of conjugated bilirubin into bile, which is then deconjugated by beta-glucuronidase, causes pigmented stones; large amounts of bilirubin may result from chronic hemolysis, and lots of deconjugation (making it available for stones) is done by beta-glucuronidases which often come from bacteria and HCs injured in infection
COPD causes increase or decrease in FRC/TRV?
increase - because air is trapped
Cystic fibrosis - effects on pancreas and absorption
pancreas is damaged in CF, so ADEK are less absorbed; avitaminosis A is most likely to contribute to squamous metaplasia of the exocrine ducts in pancreas
DDx for painful thyroid nodules
De Quervain granulomatous thyroiditis - follows infection, self-limited, may start as hyperthyroid but ends up hypothyroid; will see early inflammation but the main thing is granulomas
Medullary thyroid carcinoma may also present as neck pain; pain here is more likely than in papillary thyroid carcinoma
Describe Myeloma cast nephropathy
when a pt has MM, there’s an overproduction of Bence Jones proteins (light chains) which are filtered by the glomerulus then reabsorbed in the tubule, but when it reaches limit for reabsorption the light chains are stuck in the tubule and end up forming casts with Tamm Horsfall proteins; when peed out these casts stain intensely pink (eosinophilic)
*Not to be confused with eosinophils in the urine (drug-induced interstitial nephritis)
Describe the shape and pH of the 4 types of kidney stones
- Ca oxalate - acidic pH, square envelopes (if Ca phosphate then basic pH)
- AMP - basic pH, coffin lids, from infxn with urease+ bugs (staghorn in adults)
- Uric acid - acidic pH, rhomboid or rosettes (radiolucent - unique)
- Cystine (aa) - acidic pH, hexagonal (staghorns in kids)
Differentiating between coarctation of the aorta and PDA?
coarctation will present with BP discrepancy, PDA will present with distal extremity cyanosis
DNA polymerase III has what activity? DNA pol I has what activity?
“Pol III: 5’–>3’ synthesis; 3’–>5’ exonuclease
Pol I: same as pol III but also removes RNA primer and replaces with DNA”
Does Cushing’s/excess ACTH cause hypertrophy or hyperplasia of (what level of the adrenal cortex)?
Hyperplasia of the fasciculata and reticularis (can be diffuse or nodular)
Doxorubicin AE on heart?
dose-dependent cardiotoxicity that produces dilated cardiomyopathy
Eccentric vs Concentric LVH
both are types of hypertrophy in response to an increased load; concentric is when the muscular wall gets bigger and thicker in order to pump against inc. afterload (like Aortic stenosis); eccentric is when the ventricle gets bigger and dilated in order to deal with the increased preload (like aortic regurgitation)
Effect of sex steroids on bone growth
Initially increase linear growth; also encourage closure of the epiphyseal growth plates
Effects of insulin
“promotes synthesis of TGs, glycogen, nucleic acids, and proteins
inhibits gluconeogenesis and glycogenolysis”
Explain endothelium-dependent vasodilation
“1. stimulus (including ACh, bradykinin, shear stress, substance P, and serotonin) induces rise of IC Ca
- inc. Ca induces ENOS which converts Arginine + O2 –> NO + citrulline
- NO diffuses over to smooth muscle where it stimulates GC
- active GC converts GTP to cGMP which activates pKG which reduces IC Ca and causes relaxation of the smooth muscle”
Explain hormones involved in anovulatory cycles
without ovulation there’s no progesterone, there’s just a cyclical rise/fall in estrogen; this means that the endometrium is perpetually proliferating, and bleeds whenever it become unstable and outgrows its own blood supply, instead of on a regular cycle. Results in irregular/longer menses.
Fabry’s Disease
XLR deficiency of alpha-galactosidase A; ceremide trihexosidase accumulates; angiokeratomas, peripheral neuropthy, hypohydrosis, and eventually renal failure; differentiate from Krabbe by the angiokeratomas
Factors that make a LVOT murmur louder
“decreasing the preload or afterload - this decreases the size of the LV and brings the mitral and aortic valves closer which is part of the LVOT obstruction; this is what causes SCD in pts with HCM
*Anything that increases preload or afterload - like squatting, passive leg raise, or sustained hand grip - would decrease murmur intensity”
Fate of K+ in the renal tubules
All of it is filtered; 65% reabsorbed in the PCT; 35% reabsorbed in the TAL (NaKCC); DCT/CD regulates final concentration of K - if low then it will reabsorb, if normal/high it will secrete K+
For a patient in afib, what is the determining factor for ventricular rate?
AV node refractory period - this is the RLS since they will get signals and pass them on, it just won’t be organized signals, so they pass them on as fast as they can
bronchogenic carcinoma is #1 malignancy and
for asbestos exposure:
mesothelioma is rare; can also see pleural plaques, pulmonary fibrosis, and asbestos bodies
Gallstones in pregnancy
high estrogen causes upregulation of HMG-CoA reductase and thus the bile is hypersaturated with cholesterol, plus progesterone causes gallbladder hypomotility – resulting in cholesterol stone formation; can have same effect from OCPs
Gaucher’s disease
deficiency of glucocerebrosidase; glucocerebroside accumulates; triad = HSM, avascular necrosis of femur (severe hip/knee pain, aka Legg-Calve-Perthes disease) and osteoporosis, specific finding of MPs that look like crumpled tissue paper (Gaucher cell), yellow-brown skin pigmentation (non-specific); “young patient with easy bruising and anemia/pancytopenia, joint pain, MASSIVE liver and/or spleen, diffuse petechiae”
von Gierke disease
GSD type I - missing G-6-phosphatase, can’t get glucose OUT of the liver
Respiratory/metabolic changes in high alititude
high altitude –> hyperventilation –> blow off CO2 –> respiratory alkalosis –> kidneys secrete bicarb
Gout presents as what type of joint reaction?
acute inflammatory process; therefore treat with NSAIDs aimed at reducing PGs/NTs or Colchicine which inhibits NT activation and migration
Hepatosplenomegaly - ddx?
Gaucher (hip/knee pain), Niemann-Pick (cherry red macula), Hurler’s (gargoylism, cloudy corneas) and Hunter’s (gargolyism + aggression, no cloudy corneas)
Hgb subunits? Myoglobin? O2 dissociation curve of each
Hbg subunits = 2 alpha and 2 beta, each has a heme group; Myoglobin = monomer, 1 heme (so basically just like 1 beta subunit of Hgb); O2 dissociation curve is sigmoidal for Hgb because of the multi-heme interactions while it’s straight up and asymptote near 100% for myoglobin/monomer
High estrogen comes from where and causes what?
“thickened endometrium” - think high estrogen; if ovarian mass too - granulosa cell tumor; then look for Call-Exner bodies (description: cuboidal granulosa cells in a rosette pattern with coffee bean nuclei)
Histological presentation of kidneys following RAS
the one with the stenotic artery will be smaller and the other one will be bigger due to compensatory hypertrophy
Holosystolic murmur that increases in intensity during inspiration
tricuspid regurgitation
How are parasites killed by eosinophils?
the parasites are first covered by Abs; the eo’s then bind those Abs with their Fc receptors and that causes them to degranulate their MBP; this is a form of ADCC
How do you get neurological sx from hyperventilation?
tachypnea –> hypocapnia –> vasoconstriction (has to do with pH) –> decreased ICP
hypocapnia during hyperventilation causes neuro sx, it also causes vasoconstriction (related? dunno)
How does CHF affect lungs?
well of course you get a transudate into the interstitium, but the real effect of this is that the lung compliance is decreased because there’s distortion and swelling in the tissue and it’s harder to open the lung; creates the same net effect as pulmonary fibrosis and insufficient surfactant
How does depolarization happen in the 3 major muscle types?
“Cardiac: depolarization opens L-type CaCh, influx opens the RyR2 receptor in the SR which releases more Ca to bind troponin to let actin and myosin interact
Smooth: same as cardiac except instead of Ca binding troponin, Ca binds calmodulin and this lets actin and myosin interact
Skeletal: L-type CaCh interact directly with the RyR1 receptors and don’t need an influx of Ca to open it, then Ca binds troponin and actin/myosin interact”
How does GH make someone taller?
It acts to increase the IGF being released from the liver, which has the direct growth effects
How does PAH get cleared?
majority is filtered in glomerulus but then a lot is secreted by the PCT; none is reabsorbed
How does silicosis affect MPs?
damages them; thought that the MP eat the silicon fibers and break
How long does it take after birth for PVR to decline enough to hear a left-to-right shunt murmur?
4-10d
How to calculate the RBF using PAH?
RBF = PAH clearance = (Urine PAH * Urine Flow rate) / [PAH in plasma]
–> be careful if they give you a serum concentration; then you have to convert: Plasma = 1 - Hct
How to differentiate an Granulosa cell tumor and a Sertoli-Leydig cell tumor?
GCT –> Estrogen which will produce ABNORMAL uterine bleeding 2/2 endometrial hyperplasia, and precocious puberty
SLCT –> Testosterone which will produce virilization meaning AMENORRHEA, deep voice, hirsutism, clitoromegaly
How to differentiate dermatitis herpetiformis from atopic dermatitis that is triggered with eating certain foods?
DH is going to occur in 4-5th decade; AD typically presents in infants and usually before age 5
DH usually affects the buttocks/extensor surfaces; AD in infants will involve scalp/extensor surfaces but spare the diaper area, then in older kids will affect the flexor surfaces
DH is associated with Celiac disease, which also has LC infiltration, crypt hyperplasia (not crypt abscesses - that’s UC), and loss of villi which would make for malabsorption/steatorrhea.
AD is associated with asthma and allergic rhinitis = allergic triad.
How to recognize a pulmonary abscess
if the abscess communicates with an air passage there will be partial drainage enough for an air cavity to form which can be seen on CXR; this abscess is forming because of release of lysosomal enzymes from the dying NTs/MPs; there can also be an air-fluid level on imaging.
Symptoms = night sweats, fever, weight loss, and productive cough with foul-smelling sputum
Hypocapnia implies
alveolar hypoventilation (assuming constant rate of CO2 production)
In a patient with dementia, prior stroke, and PNA, what is the most likely cause of the PNA?
aspiration (can lead to septic shock, lactic acidosis)
Incontinence and DM1
think diabetic autonomic neruopathy–affecting detrusor muscle; also don’t feel the urge and can’t empty completely, with difficulty starting/stopping
Ivabradine
selectively inhibits funny sodium channels in the SA node cells, thereby slowing HR; it’s the only drug that has NO effect on contractility or relaxation; used in treatment of HF (reduces the risk of hospitalization)
Kidney stones and Calcium levels
#1 reason for kidney stones is hypercalciuria - makes sense because if you have too much Calcium then your body tries to dump it in the kidneys, instead of leaving it in circulation for that reason there's normal serum calcium levels
Know what direction glycolysis goes when you have high Fructose
down glycolytic pathway
Law of Conservation of Mass - as applied to a blood vessel that gets smaller
Qin = Qout --> V1*A1 = V2*A2 Q = flow; V = velocity; A = diameter of vessel
Mainstem bronchus lesion
from obstruction of the bronchus you get air trapped in the lung, then it all gets absorbed into the blood; when no more air in the alveoli –> atelectasis; trachea deviates toward side of lesion because of lower pressure when lung collapses
Major basic protein is for
for parasites, as it’s “anti-helminth”
Man with testicular tumor and hyperthyroidism - likely diagnosis?
Choriocarcinoma - because this tumor secretes hCG, the alpha subunit of which is similar between hCG, TSH, FSH, and LH (may also see gynecomastia)
Midline episiotomy will involve what structures?
vaginal lining/mucosa and perineal body
MOA of the CFTR
CFTR uses ATP hydrolysis
most common benign pulmonary lung tumor:
hamartoma - “popcorn calcifications” with islands of mature hyaline cartilage
Most frequent mechanism of SCD following MI/coronary artery occlusion
V-fib
Neurophysins
carrier proteins for ADH/oxytocin to move them down to the nerve terminal for release in posterior pituitary
Normal Pressures in cardiac cath
SVC/RA: 1-6mmHg RV: systolic is 15-30mmHg PA: diastolic is 6-12mmHg Pulm wedge: 6-12mmHg (~PA diastolic) LA: 10mmHg (higher in mitral regurg) LV: ~120mmHg (same as aorta)
Pancoast tumor is also called:
Superior Sulcus tumor
Pancreatitis is a major risk factor for what lung disease?
ARDS
What size particle are dealt with by mucociliary transport in the respiratory tract?
2.5-10 micrometers = mucociliary transport
Pentad of sx makes you think:
fever, neuro sx, RF, anemia, thrombocytopenia in the setting of GI illness
TTP-HUS or another thrombotic microangiopathy
Peripheral neuropathy (LSD) - ddx?
“EE”: Fabry (angiokeratoma) and Krabbe (optic atrophy)
Phenylalanine metabolism pathway
Phenylalanine –> Tyrosine* –> DOPA (–>melanin)
Can’t convert to Tyrosine = PKU
Can’t convert to DOPA = Albinism
*Tyrosine –> Homogentisate ->->-> Fumarate
Can’t convert Homogentisate = Alkpatonuria
Problems limited to the right heart - think
carcinoid syndrome (and most commonly, serotonin/bradykinin)
PRPP is an enzyme where?
in the purine/pyrimidine synthesis pathway; without it you get gout (deposition of needle-shaped, negatively birefringent crystals in joints)
Ras-Raf-Mek-Erk-TF - what activates Ras?
Ras is a G-protein that gets activated when it binds GTP; it’s inactivated form is when GTP is cleaved into GDP and it hangs out like that; a mutated Ras may never again cleave GTP into GDP and thus would be constitutively active always, leading to continuous proliferation/cancer
Rate of Inulin clearance best approximates ?
GFR
Ratio of phosphatidylcholine (aka lecithin) to sphingomyelin in amiotic fluid?
approximately 1:1 until week 35 (3rd trimester) when lecithin will rise sharply as fetal lungs start to produce surfactant; will rise to 2:1 or higher
Reactive arthritis - how to recognize it?
since it’s a seronegative spondyloarthropathy, look for a single involved joint about 1-4wks following an infection; may also have the other symptoms of conjunctivitis and urethritis; associated strongly with HLA-B27, but not serum markers
*Reactive arthritis may also involved sacroiliitis, dactylitis, hyperkeratotic vesicles on palms/soles, dermatitis of glans penis (circinate balanitis), and oral ulcers
Relationship between Ca and granulomatous disease
activated MPs (in granulomas) can express 1-alpha-dehydroxylase which will activate Vit D and increase Ca, independent of PTH
Relationship between PTH, Vit D, Ca, PO4, and Mg
low serum Ca or Mg will inc. PTH; really high Mg will dec. PTH; when PTH is secreted it will tell kidney to retain Ca and dump PO4 because PO4 likes to bind up free Ca; diarrhea will cause low Mg
Retinopathy of prematurity
when a baby is born premature and they have hypoplastic lungs they will be treated with O2 and/or CPAP; the hypoxia however will induce angiogenic factors in the retina, which start neovascularization when there is sufficient O2 (like when the nurse gives it) and all the neovascularization will increase the risk of retinal hemorrhage/detachment, hence retinopathy (this is a major cause of blindness in developed countries)
Roles of HGPRT and PRPP in purine synthesis
HGPRT is purine salvage and PRPP is de novo synthesis; so in the case of Lesch-Nyhan when you’re missing HGPRT you can’t keep up with all the purines that need recycling and they get shunted/stuck as Hypoxanthine/Guanine, Xanthine, and Uric acid
Signs of normal aging in the heart
sigmoid shaped ventricular septum, increased interstitial collagen/CT, and accumulation of brown cytoplasmic granules containing lipofuscin (wear and tear pigment)
Sorbitol pathway
“Glucose –> Sorbitol –> Fructose
Aldose reductase / Sorbitol dehydrogenase”
Theca cells make?
Granulosa cells make?
TAGE
Theca –> Androgens
Granulosa –> Estrogen
Thionamide induced agranulocytosis
both methimazole and PTU can produce agranulocytosis; so if a patient has fever and sore throat get a WBC with differential to rule out agranulocytosis and probably stop the drug asap; this side effect makes radioactive iodine the preferred treatment for hyperthyroidism (including Grave’s disease)
Thoracic outlet syndrome
presents as numbness, tingling, weakness, and maybe swelling (if vein involved) of the upper extremity; outlet is most commonly obstructed at the scalene triangle (formed by ant and middle scalenes and the first rib)
Thymomas or thymic hyperplasia is associated with what disease of bone marrow?
pure red cell aplasia - the thymus makes T cells that then develop a destructive affinity for RBCs only (via IgG or CTLs); this could also be due to Parvovirus B19 infection
Total PVR is lowest at ?
lowest = FRC; at max inspiration the alveoli are full of gas and put pressure on the capillaries; at max expiration there’s lots of intrathoracic pressure on the capillaries; so happy medium is where you’re not breathing in or out
Transient myocardial ischemia causes cells to increase in size. What happens?
decreased O2 causes cell to switch to anaerobic metabolism, but can’t make as much ATP so the Na/K ATPase in the membrane fails, as well as the Ca-ATPase in the mitochondrial membrane; this build up of IC Na and Ca is bad for the cell and causes swelling - the primary cause of the increased size
Failure of the SR to sequester Ca results in decreased contractility of the muscle
What aa’s anchor a protein into the cell membrane?
nonpolar, hydrophobic aa’s like: ala, val, leu, phe, tryp, met, pro, gly
What are the 2 ways to represent CO?
CO = SV * HR = O2 consumption / arteriovenous O2 difference
What are the cardinal veins?
in utero they are the veins that eventually become the systemic veins; in contrast to the umbilical and vitelline veins which degenerate and form the portal system, respectively
What are the normal partial pressures for O2 and CO2?
Normal PaO2=75-105, PAO2=105
Normal PaCO2=33-45, PACO2=40
What are the vascular changes that occur in malignant HTN? DM? atherosclerosis?
- malignant HTN - onion skinning/concentric hypertrophy of small vessels
- DM - hyaline arteriosclerosis/homogenous acellular pink material; stains pink with PAS stain
- atherosclerosis - lipid-filled intimal plaque covered by fibrous cap (ECM and fibrous cap made by VSMCs)
What cell types line the female reproductive tract?
Ovary - cuboidal; Fallopian tubes and Uterus - simple columnar; Cervix - simple columnar to stratified squamous (NK); Vagina - stratified squamous (NK)
What cofactor is most often required for transfer of groups between/to amino acids?
B6 - required for decarboxylation and transamination of amino acids, as well as for gluconeogenesis
What do hemosiderin laden MPs look like and how do they stain?
golden cytoplasmic granules within MPs that stain blue with Prussian blue (stains the iron in the blood)
What do the enzymes PNMT, COMT, and MAO do?
“PNMT: converts NE to Epi
COMT: breaks down NE –> normetanephrine; Epi –> metanephrine
MAO: breaks down NMN/MN into vanillylmandelic acid (VMA)”
What do the Purkinje PM cells do?
they are ectopic PM cells that can assume pacemaker activity during bradycardia
What does Buerger disease look like?
they’ll tell you it’s an Asian male (young) who has something to do with smoking/tobacco - could be hypersensitivity rxn to tobacco component; and they have vascular insufficiency in the extremities, and this segmental vasculitis is unique in that it extends into contiguous veins and nerves
What does left dominant circulation mean?
That the PDA is fed primarily by the Left coronary circulation, specifically the L circumflex artery.
The PDA also gives rise to the AV nodal artery; so whichever coronary is dominant, that the one that feeds the AV node.
What factors affect airway resistance?
airway resistance is increased by smaller diameter and turbulent airflow (in larger diameter); it’s decreased by total cross sectional area which is maximal in small bronchi and beyond
What form of O2 in blood doesn’t change?
partial pressure of dissolved O2
What happens to C peptide?
it gets cleaved from the proinsulin molecule by beta-peptidases but is secreted alongside, so it ends up in circulation
What happens to the thyroid pool when you take Estrogen/Progesterone?
estrogen increases the amount of TBG, so more thyroid is bound up and less free T3/T4 - this feeds back to pituitary to increase TSH; TH then saturates the TBG and repletes the free T3/T4; so net effect is that the total TH goes up while free T3/T4 stays the same
What is a glomangioma and where is it found?
a tumor of the modified smooth muscle cells of a glomus body, which is a small encapsulated neurovascular organ found in the dermis of the nail bed, finger/toe pads, and ear; the glomus body functions to sense the temp and dilate or constrict to let heat out/in
What is PFK1 and PFK2 and when are they active?
PFK1 converts F-6-P to F-1,6-BP in glycolysis.
PFK2 converts F-6-P to F-2,6-BP in the side path that is going to sense whether you need to run glycolysis or not.
Fed state: inc. F-2,6-BP will push PFK1 to run glycolysis.
Fasting state: Glucagon has inc. cAMP/pKA which drives PFK2 backwards to make more F-6-P to turn into glucose (MAIN GOAL = GLUC)
What do Homeobox genes code for?
transcription factors that alter expression of genes that will result in the cranio-caudal segmentation of the embryo; mutations in these genes will result in improperly placed organs and limbs and skeletal abnormalities
Amitryptiline
a TCA with strong anticholinergic properties