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1

How many half-lives does it take for a drug infused at a constant rate to reach 94% of steady state? What variables determine the half-life of a drug? (FA15 p243) (FA16 p237)

about 3.3 half-lives (90%, 4-5 to reach steady state)
2 half lives: 75%
3: 87.5%
4: 93.75%

half life (t1/2) = (0.7 x Vd)/CL
-volume distribution and clearance

2

Describe the anatomical layers of the penis

outer dermis
dartos fascia
deep (Buck's) fascia
tunica albuginea
2 corpora cavernosa (dorsal/top)
1 corpus spongiosum (ventral/bottom) -urethra inside

3

What is the mechanism of action of penicillin? Is it a bacteriostatic or bactericidal antibiotic? (FA15 p180) (FA16 p170)

bacteriocidal, binds PBPs (PCN binding proteins) and blocks cell wall synthesis via inhibiting PTG cross-linking

4

What is the adult remnant of each of the following fetal structures? (FA15 p271, 569) (FA16 p264, 573)
Gubernaculum (female)
Processus vaginalis (male)
Foramen ovale
Notochord

Gubernaculum (female): round ligament of uterus + ovarian ligament
Processus vaginalis (male): tunica vaginalis
Foramen ovale: fossa ovalis
Notochord: Nucleus pulposus

5

A 37-year-old patient with refractory peptic ulcer disease undergoes an esophagogastric duodenoscopy (EGD). Biopsies of the duodenum reveal hypertrophied submucosal glands. What are these glands? What are Peyer’s patches? How can these structures help you identify the location from which a histological specimen was taken? (FA15 p345, 360, 356) (FA16 p341, 357, 352)

Brunner glands (HCO3−-secreting cells of submucosa) (*duodenum*) :hypertrophy implies PUD, etc.

Peyer patches (lymphoid aggregates in lamina propria, submucosa) (*ileum*), MALT

6

A person eating fugu sashimi in Japan is at risk for what toxicity? What is the mechanism of this toxicity? (FA15 p252) (FA16 p250)

Tetrodotoxin
Highly potent toxin that binds fast voltage-gated Na+ channels in cardiac and nerve tissue, preventing depolarization (blocks action potential without changing resting potential).
Causes nausea, diarrhea, paresthesias, weakness, dizziness, loss of reflexes. severe: coma, respiratory arrest, CV collapse
tx: supportive

7

You are performing a well-child examination on a 4-year-old girl. The patient was recently adopted after being removed from the biological mother for abandonment. What changes might you see in your evaluation? What are the effects seen in an infant when there is long-term deprivation of affection? (FA15 p506) (FA16 p510)

Long-term deprivation of affection results in: 􏰂 Failure to thrive, Poor language/socialization skills, Lack of basic trust, Anaclitic depression (infant withdrawn/ unresponsive)
The 4 W’s: Weak, Wordless, Wanting (socially), Wary.
Deprivation for more than 6 months can lead to irreversible changes.
Severe deprivation can result in infant death.
-malnutrition and hygiene/dental issues

8

Which antifungal drugs cause gynecomastia and by what mechanism? Which diuretic drug causes gynecomastia and by what mechanism? (FA15 p191, 554) (FA16 p182, 558)

ketoconazole: inhibition of testosterone synthesis via inhibiting desmolase (cholesterol-->pregnenolone), also weak testosterone receptor antagonist

spironolactone: antiandrogen, ^conversion of testosterone-->estradiol (causing gynecomastia) and blocks testosterone synthesis; testosterone receptor antagonist

9

A 25-year-old woman presents to the clinic with severe pelvic pain that is always associated with menses. What diagnosis is characteristic of this type of pain and often results in infertility? What is the classic finding on the ovary that is associated with this diagnosis? (FA15 p588) (FA16 p594)

endometriosis
"chocolate cyst" ovary (endometrioma); normal-sized uterus

10

What are the early cyanotic heart diseases? What are the late cyanotic heart diseases? (FA15 p288- 289) (FA16 p282-283)

early: R-->L shunts; "blue babies"
5 T's: Truncus arteriosus (1 vessel), Transposition (2 switched vessels), Tricuspid atresia (3=Tri), Tetralogy of Fallot (4=tetra), TAPVR (5 letters)

late: L-->R shunts; "blue kids"
VSD>ASD>PDA; also Eisenmenger syndrome

11

causes K+ to shift OUT of cell (inducing hyperkalemia)

Digitalis (blocks Na+/K+ ATPase)
HyperOsmolarity
Lysis of cells (e.g., crush injury, rhabdomyolysis, cancer)
Acidosis
β-blocker
High blood Sugar (insulin deficiency)
Patient with hyperkalemia? *DO LAβS*

12

causes K+ to shift into cells (inducing hypokalemia)

Hypo-osmolarity
Alkalosis
β-adrenergic agonist (􏰄Na+/K+ ATPase) Insulin (􏰄Na+/K+ ATPase)
Insulin shifts K+ into cells


13

e-lyte disturbance: Nausea and malaise, stupor, coma, seizures

hyponatremia

14

e-lyte disturbance: U waves on ECG, flattened T waves, arrhythmias, muscle spasm

hypokalemia

15

e-lyte disturbance: Tetany, seizures, QT prolongation

hypocalcemia

16

e-lyte disturbance: Tetany, torsades de pointes, hypokalemia

hypomagnesia?

17

e-lyte disturbance: Bone loss, osteomalacia (adults), rickets (children)

hypophosphatemia

18

e-lyte disturbance: Renal stones, metastatic calcifications, hypocalcemia

hyperphosphatemia

19

e-lyte disturbance: decreased DTRs, lethargy, bradycardia, hypotension, cardiac arrest, hypocalcemia

hypermagnesia

20

e-lyte disturbance: Stones (renal), bones (pain), groans (abdominal pain), thrones (􏰄urinary frequency), psychiatric overtones (anxiety, altered mental status), but not necessarily calciuria

hypercalcemia

21

e-lyte disturbance: Wide QRS and peaked T waves on ECG, arrhythmias, muscle weakness

hyperkalemia

22

e-lyte disturbance: Irritability, stupor, coma

hypernatremia

23

consequences of renal failure

"MAD HUNGER"
Metabolic Acidosis
Dyslipidemia (especially 􏰄 triglycerides)
Hyperkalemia
Uremia—clinical syndrome marked by ^ 􏰄BUN: Nausea and anorexia, Pericarditis, Asterixis, Encephalopathy, Platelet dysfunction
Na+/H2O retention (HF, pulmonary edema, hypertension)
Growth retardation and developmental delay
􏰂Erythropoietin failure (anemia)
􏰂Renal osteodystrophy

24

ACE inhibitor SEs

Captopril’s CATCHH.
Cough, Angioedema (contraindicated in C1 esterase inhibitor deficiency), Teratogen (fetal renal malformations), ^Creatinine (decreased 􏰃GFR), Hyperkalemia, and Hypotension. Avoid in bilateral renal artery stenosis, because ACE inhibitors will further􏰃 decrease GFR-->􏰅renal failure.

25

drugs that cause gynecomastia

"Some Drugs Cause Awesome Knockers"
Spironolactone
Digitalis
Cimetidine
Alcohol
Ketoconazole

26

For what conditions is hyperbaric oxygen therapy particularly helpful?

CO poisoning-->carboxyhemoglobin (binds Hgb w. 200x more affinity than O2)
the bends (decompression sickness)
arterial gas emboli
gas gangrene (C. perfringens)
osteomyelitis
acute MI

27

What is the pressure in the potential spaces of the body including the pleural cavity, the joint spaces, and the pericardial cavity?

negative, facilitates diffusion of fluids in
pleural cavity: -7 to -8 cm H2O
joint spaces: -3 to -5 cm H2O
pericardial cavity: -5 to -6 mmHg

28

If stroke volume determines cardiac output, and contractility determines stroke volume, what determines contractility? (FA15 p273) (FA16 p267)

increases with:
Catecholamines (^􏰄activity of Ca2+ pump in
sarcoplasmic reticulum)􏰂/sympathethic stimuation
^􏰄intracellular Ca2+
^􏰃extracellular Na+ (dec. 􏰃activity of Na+/Ca2+ exchanger)
􏰂Digitalis (blocks Na+/K+ pump-->􏰅􏰄intracellular Na+-->dec. 􏰅􏰃Na+/Ca2+ exchanger activity-->^􏰅􏰄intracellular Ca2+)

decreases with:
β1-blockade (dec.􏰃 cAMP) HF with systolic dysfunction 􏰂
Acidosis
􏰂Hypoxia/hypercapnia (􏰃dec. Po2/^Pco2)
Non-dihydropyridine Ca2+ channel blockers (verapamil, diltiazem)
decreased IC Ca2+, ^EC Na+ (opposite digoxin/digitalis)

29

A 48-year-old man presents to your office with a persistent cough that has become bloody. Chest x- ray reveals a coin lesion within the lung parenchyma. Further workup reveals that the patient has the most common type of lung cancer in nonsmokers. Which cancer is this? What other lung cancers are not associated with smoking? Which lung cancers are associated with smoking, and where are they located, centrally or peripherally? (FA15 p619) (FA16 p626)

bronchial adenocarcinoma
other non-smoking cancers: bronchioloalveolar adenocarcinoma, malignant mesothelioma (pleural)

others: small cell (oat cell), squamous, large cell, non-small cell, bronchial carcinoid tumor

smokers: small cell, squamous; "sentrally" located

30

How does standard deviation differ from standard error of the mean? (FA15 p53) (FA16 p37) Which one is used in calculating confidence intervals? (FA15 p54) (FA16 p38)

Standard deviation = how much variability exists from the mean in a set of values.
Standard error of the mean = an estimate of how much variability exists between the sample mean and the true population mean.
= standard deviation/ square root of #number of subjects (larger population, lower SEM)
CI= confidence interval= range from [mean-Z(SEM)] to [mean+Z(SEM)]
95% CI, Z=1.96
99% CI, Z=2.58