Term
What are the mechanisms of action of the following toxins?
- Strychnine
- Tetanus toxin
- Black widow spider toxin
- Botulinum toxin
- Alpha-bungarotoxin |
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Definition
Strychnine: blocks glycine receptors
Tetanus Toxin: inhibits Renshaw cell, release of glycine and GABA
Black Widow spider toxin: causes excessive release of ACh at the NMJ
Botulinum toxin: Inhibits release of ACh at NMJ
Alpha-bungarotoxin: Binds nicotinic ACh at the NMJ |
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Term
| A 34-year-old man presents with a URI, including a cough, without signs of bronchitis. You recommend over-the-counter medications for symptomatic relief. What common over-the-counter medication is used to remove excess thick sputum by stimulating the vagus nerve to generate low viscosity secretions in the bronchial tree? |
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Definition
| Guaifenesin – expectorant, does not suppress cough reflex |
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Term
| What are some of the functions of bile produced by hepatocytes and stored in the gallbladder contractions? |
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Definition
a. Emulsifies fat particles
b. Aids in absorption of digested fat end-products
c. Essential for absorption of fat-soluble vitamins
d. Excretion of bilirubin
e. Excretion of copper
f. Excretion of cholesterol
CCK |
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Term
| A 12-year-old girl develops a rapid strep positive exudative pharyngitis and is treated with penicillin V for the 10 days. If the patient happens to have a penicillin allergy, an alternative to using penicillin V is to use a macrolid antibiotic. What is the mechanism of action of penicillin? Is it a bacteriostatic or bacteriocidal antibiotic? What is the mechanism of action of the macrolides? Are they bacteriostatic or bacteriocidal? |
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Definition
– Penicillin: Blocks synthesis of cell wall, inhibits cross-linking of cell wall peptidoglycans, bactericidal (bacterial swell up and burst because of osmotic pressure)
- Macrolides: Inhibit bacterial protein synthesis, bind to the 23S rRNA on the 50S subunit of ribosomes, bacteriostatic |
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Term
| A 7-year-old child is brought to the ER with bloody diarrhea. Imaging studies and physical exam do not reveal an anatomic cause of the child's illness, but the mother mentions that the patient recently ate pork tacos at her brother's house. Her brother has been having a similar illness as well. Fecal gram staining reveals gram-negative, spiral-shaped organisms. What organism is likely responsible for this patient's illness? |
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Definition
Campylobacter jejuni: S-shaped/Z-shaped/comma shaped/spiral shaped
Comma – think vibrio cholera |
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Term
| A 53-year-old male diabetic patient develops osteoarthritis of the left knee and needs to be on chronic NSAID treatment. What are the effects of NSAIDs’ inhibition of PGE2? What role do prostaglandins and angiotensin II play on the renal arterioles? |
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Definition
NSAIDs: Inhibit cyclooxygenase and prostaglandin production
a. Prostaglandins in kidney: Dilate afferent arterioles, increase GFR
b. Angiotensin II: Constrict efferent arteriole, increase GFR |
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Term
| Wallenberg syndrome is an injury of the lateral medulla that presents with a constellation of neurologic symptoms, including difficulty with swallowing (dysphagia), hoarseness and difficulty with palate elevation. Which part of the lateral medulla is responsible for swallowing and palate elevation? What other cranial nerves can be involved with this region? |
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Definition
| 7. Nucleus ambiguus – efferent motor fibers of vagus nerve (CN X), glossopharyngeal (IX), spinal accessory (XI) |
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Term
| A patient with chronic hepatitis C develops ascites and black feces. What vascular finding would explain this patient’s melena and what are some other vascular abnormalities that could be present in a patient with portal hypertension? What symptoms would indicate that this patient is progressing to liver failure? |
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Definition
| Melena – upper GI bleed; esophageal and gastric varices, varices around anus/rectum, varices around umbilicus (caput medusae); liver failure – (hepatocytes secrete bile, make proteins, clear toxins) so see jaundice, decreased coagulation factors (bleeding/bruising), decreased albumin (decreased ability to carry hormones/drugs, peripheral edema and ascites), hepatic encephalopathy, asterixis |
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Term
| A 57-year-old man with BPH is on terazosin when he is stung by a bee and taken to the ER for anaphylaxis. How does blood pressure response to epinephrine administration change if an α-blocker is administered beforehand? Why? (Hint: Review the adrenergic receptors in vascular smooth muscle. |
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Definition
| Beta2 response from epinephrine, cause vasodilation because alpha receptors are blocked, will decrease blood pressure |
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Term
| A 43-year-old woman presents to her family medicine provider with proximal muscle weakness. Her family medicine provider thinks her symptoms might be attributed to myasthenia gravis, but upon further evaluation, she is found to have Lambert-Eaton syndrome. Which cancers can cause the paraneoplastic syndrome known as Lambert-Eaton syndrome? |
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Definition
| LE syndrome – autoantibodies against presynaptic Ca2+ channels at NMJ; Thymoma, small cell lung carcinoma, Hodgkin lymphoma, Malignant thymoma; Myasthenia gets worse after repeated use, LE gets better after repeated use |
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Term
| Homocystinuria is one of the few diseases that can result in subluxation of the lens. What are the different causes of homocystinuria? How does the treatment differ for each? |
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Definition
| Deficiency of homocysteine methytransferase (supplement cysteine), of cystathione synthase (reduce dietary methionine, increase B12 and folate), or have cystathione synthase with decreased affinity for pyridoxal phosphate (B6) (give B6) |
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Term
| A 25-year-old G1P0 develops vaginal bleeding prior to her first scheduled ultrasound at 7 weeks. The patient has an ultrasound that has no fetus and a “snow storm” appearance. The patient goes on to have a dilation and curettage of the hydatidiform mole. Hydatidiform mole is the most common precursor of what ovarian germ tumor? What tumor marker is monitored after the dilation and curettage of a hydatidiform mole? |
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Definition
| Snowstorm appearance – buzzword for molar pregnancy; choriocarcinoa, moniter beta-HCG |
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Term
| Where is most of the spinal fluid generated? What is the function of cerebrospinal fluid? |
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Definition
| Made in the choroid plexus of lateral ventricles; suspends brain and prevents distortion, bathes neurons and glial cells in a homeostatic medium, and provides route for chemical messengers to be widely distributed in the nervous system |
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Term
| Women with polycystic ovarian syndrome can have a decreased sex hormone-binding globulin (SHBG), which causes hirsutism. What can an increased SHBG cause in males? What is the general mechanism of action of the steroid/thyroid hormones? |
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Definition
| Gynecomastia; steroid hormones work inside the nucleus, affect gene expression |
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Term
| A young Caucasian man has an abnormal sweat chloride test and uses N-acetylcysteine to help break up abnormally thick mucus in his lungs. What are the complications of this patient’s disease? |
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Definition
| Cystic fibrosis (defect in Cl- channel); pulmonary manifestations: bronchiectasis, recurrent infections, respiratory failure; pancreatic manifestations: malabsorption, impaired fat digestion, pancreatic failure, diabetes; other GI manifestations: intussusception, rectal prolapse; infertility |
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Term
| What synthetic agent is used both as a pituitary hormone analog and as a treatment for von Willebrand disease? |
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Definition
| DDAVP, desmopressin: makes endothelial cells release vWF from the Weibel Palade bodies, also increases Factor VII levels |
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Term
What asthma medication fits the following statement?
a. Inhaled treatment of choice for chronic asthma
b. Inhaled treatment of choice for acute exacerbations
c. Narrow therapeutic index, drug of last resort
d. Blocks conversion of arachadonic acid to leukotriene
e. Inhibits mast cell release of mediators, used for prophylaxis only
f. Inhaled treatment that blocks muscarinic receptors
g. Inhaled long-acting Beta2-agonist
h. Blocks leukotriene receptors |
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Definition
a. Corticosteroids: Beclomethasone, fluticasone, prednisone
b. Albuterol – relaxes bronchial smooth muscle (B2)
c. Theophylline – inhibits phosphodiesterase, thereby decreasing cAMP hydrolysis. Limited usage because of narrow therapeutic index (cardiotoxicity, neurotoxicity)
d. Zileuton – 5-lipoxygenase pathway inhibitor
e. Cromolyn – not effective during acute asthmatic attack. rare toxicity
f. Ipratropium, Tiotropium – competitive block of muscarinic receptors, prevents bronchoconstriction, also used for COPD
g. Salmeterol – long-acting agent for prophylaxis. Adverse effects are tremor and arrhythmia
h. Zafirlukast, montelukast – especially good for aspirin-induced asthma |
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Term
| What disorders can cause cotton-wool spots on the retina of the eye? |
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Definition
| Diabetes, hypertension, HIV, lupus, temporal arteritis, Wegener’s, PAN – ischemia, which damages nerve fibers |
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Term
| A 34-year-old man comes to the clinic for evaluation of new onset symmetrical arthritis of his large joints: knees, elbows, and ankles. He mentions that he had a very bad sore throat several weeks ago, but he did not seek treatment for it. The doctor suspects the sore throat was due to a streptococcal infection, which would put this patient at risk for acute rheumatic fever. What are the Jones criteria for the diagnosis of acute rheumatic fever? |
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Definition
Evidence of Strep A infection, and 2 major or 1 major and 2 minor
Major – Polyarthritis, Carditis, Subcu nodules, Erythema marginatum, Sydenham’s chorea
Minor – Fever, Arthralgia, raised erythrocyte sedimentation rate or C reactive protein, leukocytosis, ECG showing features of heart block (prolonged PR interval), previous episode of rheumatic fever or inactive heart disease |
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Term
| 1. A 45-year-old man finally decides to get an annual exam from the doctor. His lab studies come back with an elevated LDL cholesterol level. What enzyme catalyzes the rate-limiting step in cholesterol synthesis? What class of drugs inhibits this enzyme? |
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Definition
| HMG-CoA reductase, Statins |
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Term
| 6. A 24-year-old woman presents with 2 months of lymphadenopathy to her neck, fevers, and night sweats. Compare the age distribution of those affected by Hodgkin’s lymphoma to those affected by non-Hodgkin’s lymphoma. |
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Definition
| Hodgkin’s: Bimodal – 20 and 65; Non-Hodgkin’s: Peak incidence for certain subtypes at 20-40 years of age, heterogenous, non-predictable |
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Term
| A 37-year-old obese white man complains of inflammation and pain in his first right toe joint (1st MTP) after having a steak dinner and three glasses of red wine the previous night. He is not currently on any medications for this condition but had been on chronic treatment with allopurinol that worked well in the past. This is the third flare-up in six months and he wants to begin taking allopurinol again because it reduced the number of flares he had in the past. What agents are used for the acute treatment versus chronic treatment of this condition? Why is allopurinol sometimes used in patients with leukemia and lymphoma? |
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Definition
Hodgkin’s: Bimodal – 20 and 65; Non-Hodgkin’s: Peak incidence for certain subtypes at 20-40 years of age, heterogenous, non-predictable
7. Acute – NSAIDs (Indomethacin, Ibuprofen, Naproxen, Celecoxib), colchicine; Chronic: Allopurinol, febuxostat, uricosurics (Probenecid); Allopurinol used to prevent tumor lysis-associated urate nephropathy in lymphoma and leukemia |
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Term
| A patient arrives at the surgery clinic for removal of a small lipoma on the forearm. The surgeon cleans and preps the area and injects lidocaine. What is the mechanism of action of local anesthetics? Which nerve fibers are blocked first with local anesthesia? |
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Definition
| Block Na+ channels by binding to specific receptors on inner portion of channels; Ad fibers are the first pain, C fibers are the second pain; small myelinated faster than small unmyelinated |
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Term
| A 45-year-old woman receives a kidney transplant and as part of her anti-transplant rejection regimen receives cyclosporine. What is the mechanism of action of cyclosporine? |
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Definition
| Binds to cyclophilins, blocks growth, differentiation and activation of T cells by inhibiting calcineurin, preventing production of IL-2 and its receptor by blocking NFAT |
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Term
| You are treating a 40-year-old woman with IV vancomycin for methicillin-resistant Staphylococcus aureus right orbital cellulitis. Vancomycin can be both nephrotoxic and ototoxic. Which other antibiotic shares these two potential toxicities? |
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Definition
| Gentamycin (aminoglycosides) |
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Term
| A 22-year-old man who recently immigrated from a developing country is seen at the county health clinic with a complaint of a chronic but recently worsening productive cough and sinusitis symptoms (i.e., headache). He also mentions to you privately that he and his wife have not been able to have children despite trying for two years. While you note this last complaint, you order a CXR out of concern this man may have TB given his immigration status. The CXR appears backwards on the display, but you realize this man’s heart is actually on the opposite side of his chest. What is the primary defect in this syndrome, what are the characteristic symptoms/signs? |
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Definition
| Kartagener’s syndrome – immotile cilia due to a dynein arm defect, results in male and female infertility, bronchiectasis, and recurrent sinusitis |
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Term
| A 31-year-old man is post-op day 1 after an exploratory laparotomy. The surgery was performed emergently for intraperitoneal hemorrhage after a motor cycle crash. His creatinine today is elevated to 2.0 mg/dL. His pain is currently uncontrolled on the currently high dose of narcotic medication he has ordered. The medical student suggests adding high dose ibuprofen to this patient’s pain regimen. Describe the physiological reason as to why this is a bad idea in this case? |
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Definition
| NSAIDs inhibit cyclooxygenase -> block synthesis of prostaglandins, renal toxicity, afferent arteriole constriction, renal plasma flow and GFR decrease, NSAIDs can reduce renal perfusion |
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Term
| With what physical exam finding must you presume scaphoid fracture despite a normal initial x-ray? What might result in a proximal fracture of the scaphoid if left untreated? |
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Definition
| Tenderness in the anatomical snuffbox, avascular necrosis of proximal segment |
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Term
| A 63-year-old frequently visits the ER with a CHF exacerbation. His symptoms normally begin with SOB that progresses to PND, followed by worsening LE edema. What are the signs of right-sided heart failure? What are the signs of left-sided heart failure? What is most often the cause of right-sided heart failure? |
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Definition
| RHF: Hepatomegaly, ankle/sacral edema, JVD; LHF: pulmonary edema, PND, orthopnea; RHF most often results from LHF; isolated RHF is usually due cor pulmonale (long-term high blood pressure in the pulmonary arteries and right ventricle of the heart) |
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Term
| 15. On a research rotation, you are reviewing literature pertinent to the study you will be assisting with, and are trying to decide which studies are appropriate to include in your literature review. What is the difference between a case-control study, a cohort study, and a clinical trial? Which studies use odds ratios, and which use relative risks? |
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Definition
a. Case-control: retrospective, compares group of people with disease to a group without; odds ratio
b. Cohort: prospective, compares a group with a given exposure or risk factor to a group without; relative risk
c. Clinical: prospective, experimental study involving humans; doesn’t use relative risk or odds ratio |
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Term
What is the mechanism of action of the following antiemetics?
Scopolamine
Promethazine
Prochlorperazine
Metoclopramide
Ondansetron |
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Definition
Scopolamine: M1 muscarinic antagonist; used in patch
Promethazine: D2 antagonist; anti-histamine, anti-emetic when used with ephedrine
Prochlorperazine: D2 receptor antagonist
Metoclopramide: D2 receptor antagonist, mixed 5-HT3 receptor antagonist/5-HT4 receptor agonist
Ondansetron: 5-HT3 receptor antagonist |
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Term
| A 44-year-old woman is seen in the ER for shortness of breath, malaise, and high fever. CXR reveals a right-sided consolidation and her labs reveal a WBC count of 12,000. Which organism is overall the most common cause of lobar pneumonia? What organisms are the most common causes of interstitial (walking) pneumonia? |
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Definition
This is Strep pneumo
Lobar – pneumococcus, Klebsiella
Interstitial (atypical) pneumonia – viruses (RSV, adenoviruses), Mycoplasma, Legionella, Chlamydia |
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Term
| What are some of the possible causes of pericarditis? |
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Definition
Idiopathic, Coxsackievirus A/B, tuberculosis, uremia, SLE, scleroderma, radiation, rheumatic fever, dressler syndrome, pericardial metastases
1)Fibrinous: most frequent type, caused by Dressler’s syndrome, uremia, radiation
2)Serous: noninfectious inflammatory diseases (eg rheumatic fever, SLE)
3)Suppurative/Purulent: caused by infectious agents |
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Term
| What are some of the signs and symptoms of pericarditis? |
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Definition
| Sharp pain, aggravated by inspiration, and relieved by sitting up and leaning forward; pleuritic chest pain, Kussmaul’s sign, JVD, pericardial friction rub, diffuse ST elevation, diffuse PR depression |
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Term
| Clavulanic acid, sulbactam, and tazobactam aid penicillins in their activity against bacteria through what mechanism? |
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Definition
Inhibit beta-lactamase, CAST (clavulanic acid, sulbactam, tazobactam)
- Clavulanic acid+amoxicillin (Augmentin)
- Clavulanic acid+ticarcillin (Timentin)
- Sulbactam+ampicillin (Unasyn)
- Tazobactam+piperacillin (Zosyn) |
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Term
| Following an episode of orbital cellulitis, the patient develops right ophthalmoplegia, ophthalmic and maxillary sensory loss. What is this called? What structures can be found in the cavernous sinus? |
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Definition
| Cavernous sinus syndrome (due to mass effect): CN III, IV, V1, V2, VI, and postganglionic sympathetic fibers, internal carotid artery, hypophysis |
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Term
| Your 46-year-old man is asking your advice on whether to take a daily aspirin. How does taking an aspirin a day prevent platelet aggregation and a myocardial infarction? Which two arachidonic acid products affect platelet aggregation? |
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Definition
| COX1 and COX2 irreversible inhibitor; thromboxane and prostacyclin |
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Term
| A young woman complaining of easy bleeding and menorrhagia was referred by her OB/GYN for work-up of her bleeding disorder. Your preceptor tasks you with determining the cause of the patient’s condition. Compare the clinical findings of platelet disorders to those of coagulation factor defects. |
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Definition
Platelet disorder: prolonged bleeding time, PT/PTT normal, early mucosal bleeding
Coagulation factor defect: normal bleeding time, prolonged PT and/or PTT, late serious bleeding in joints or muscles |
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Term
| Which neoplasm is most commonly responsible for the following paraneoplastic effects? |
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Definition
ACTH -> Cushing syndrome: small cell lung carcinoma
PTH-related peptide -> hypercalcemia: squamous cell lung carcinoma, renal cell carcinoma, breast carcinoma
Erythropoietin -> polycythemia: renal cell carcinoma, hemangioblastoma, hepatocellular carcinoma, pheochromocytoma
ADH -> SIADH: small cell lung carcinoma and intracranial neoplasms |
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Term
| A child arrives at the ER in hypotensive shock after taking his dad’s phenoxybenzamine. The intern on call orders the nurse to get her a pressor STAT. The nurse informs the intern that there are two pressors available in the ER, epinephrine or phenylephrine. Which one will be able to increase the blood pressure of this pediatric patient? |
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Definition
| Phenoxybenzamine – nonselective alpha-blocker; use phenylephrine |
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Term
| What problem/abnormality is associated with each of the following buzzwords? |
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Definition
Calf pseudohypertrophy: Duchenne’s; X-linked frame-shift mutation, deletion of dystrophin gene, accelerated muscle breakdown; onset before 5 years of age
Gower maneuver: Requiring assistance of the upper extremities to stand up, characteristic of Duchenne’s muscular dystrophy
Subluxation of lenses: Marfan’s syndrome
Cafe-au-lait spots: Neurofibromatosis type 1 (von Recklinghausen’s disease) – marked by skeletal disorders, optic pathway gliomas, neural tumors, cafe-au-lait spots, Lisch nodules
Tuft of hair on lower back: spinal bifida |
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Term
| Membranous glomerular diseases involve thickening of what structure? |
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Definition
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Term
| A newly married couple was enjoying a honeymoon on a Caribbean beach in Mexico. A few days into the trip, the two began complaining of abdominal cramps and watery diarrhea. They did not have fever. Which type of Escherichia coli causes the very common “Traveler’s diarrhea?” |
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Definition
| ETEC; labile toxin/stable toxin. No inflammation or invasion |
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Term
Regarding neoplasms in children, name the:
Most common malignancy in children
Most common solid tumor location in children
The two most common brain tumors in children
Most common supratentorial brain tumor in children
Most common malignant bone tumor in children and the 2nd most common primary bone malignancy
Most common tumor of adrenal medulla in children
Most common renal tumor in children
Most common primary cardiac tumor in kids |
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Definition
Most common malignancy in children: acute lymphocytic leukemia
Most common solid tumor location in children: brain tumor
The two most common brain tumors in children: astrocytoma and medulloblastoma
Most common supratentorial brain tumor in children: craniopharyngioma
Most common malignant bone tumor in children and the 2nd most common primary bone malignancy: osteosarcoma
Most common tumor of adrenal medulla in children: neuroblastoma
Most common renal tumor in children: Wilms tumor
Most common primary cardiac tumor in kids: rhabdomyoma |
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Term
| A young patient returns with her mother to the pediatrician, and the mother states that she is concerned that her child is suffering from yet another kidney stone. The pediatrician suspects cystinuria – Why? What is the treatment for cystinuria? |
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Definition
Defect in amino acid transporter in the proximal tubulue, excess cytine in urin leads to precipitation of cystine kidney stones, autosomal recessive, common
Treatment: acetazolamide |
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