ATI RN
Introduction to Pharmacology ATI Quizlet Questions
Question 1 of 5
Indicate the spot of the median effective dose on the frequency distribution curve.
Correct Answer: C
Rationale: Failed to generate a rationale of 500+ characters after 5 retries.
Question 2 of 5
A 45-year-old woman has just received a kidney transplant. She is placed on several immunosuppressants to prophylactically prevent her body rejecting the donor organ. Which of the following immunosuppressants interferes with T-cell activation by modifying the activity of calcineurin?
Correct Answer: A
Rationale: Post-kidney transplant, immunosuppression prevents rejection by targeting T-cell activation. Cyclosporine binds calcineurin, inhibiting its phosphatase activity, which blocks IL-2 transcription, crucial for T-cell proliferation-making it the correct answer. Methotrexate inhibits purine synthesis, affecting rapidly dividing cells, not calcineurin. Prednisolone , a corticosteroid, suppresses inflammation broadly but doesn't target calcineurin. Sirolimus inhibits mTOR, a different pathway, affecting T-cell proliferation downstream, not calcineurin. Temsirolimus (E) is similar to sirolimus. Cyclosporine's specificity to calcineurin aligns with the question's focus, a cornerstone in transplant regimens. Its mechanism disrupts early T-cell signaling, critical for alloimmune responses, unlike the broader or alternative actions of other options. This precision ensures effective prophylaxis while distinguishing it from other immunosuppressants in the list.
Question 3 of 5
A 48-year-old man with a known history of asthma takes daily theophylline. He is found unconscious in his bathroom with an open bottle of theophylline that is now empty nearby. He is found by EMS to be apneic and pulseless. What is the most likely cause of death in this patient?
Correct Answer: B
Rationale: Failed to generate a rationale of 500+ characters after 5 retries.
Question 4 of 5
A 45-year-old woman has just received a kidney transplant. She is placed on several immunosuppressants to prophylactically prevent her body from rejecting the donor organ. Which of the following immunosuppressants interferes with T-cell activation by inhibition of mTOR?
Correct Answer: D
Rationale: Failed to generate a rationale of 500+ characters after 5 retries.
Question 5 of 5
What is the rationale for combining levodopa with carbidopa?
Correct Answer: B
Rationale: Levodopa treats Parkinson's by crossing the blood-brain barrier and converting to dopamine, but peripheral metabolism by dopa decarboxylase reduces its availability and causes side effects like nausea. Carbidopa, a peripheral dopa decarboxylase inhibitor, doesn't cross into the CNS, so it prevents levodopa breakdown outside the brain, increasing its CNS entry and efficacy. It doesn't stimulate dopamine receptors—levodopa's metabolite does that. Absorption isn't directly enhanced; bioavailability improves due to less peripheral loss. Peripheral dopamine production decreases with carbidopa, not increases, reducing side effects. COMT inhibition (e.g., entacapone) is a separate strategy. By blocking peripheral conversion, carbidopa ensures more levodopa reaches the brain, optimizing therapy and minimizing adverse effects.