Nokea
Which of the following most accurately describes the antibacterial mechanism of penicillin:
- A. inhibits DNA synthesis
- B. inhibits the terminal step in peptidoglycan synthesis
- C. Inhibits protein synthesis in growing bacterial cells
- D. disrupts the integrity of the cell membrane
Correct Answer: B
Rationale: Penicillin is a type of antibiotic that works by inhibiting bacterial cell wall synthesis. Peptidoglycan is a critical component of the bacterial cell wall, providing structural support and preventing the cell from bursting. Penicillin specifically targets the final step in peptidoglycan synthesis, known as cross-linking, by binding to and inhibiting the enzyme transpeptidase. Without proper cross-linking of peptidoglycan, the bacterial cell wall becomes weak and compromised, leading to cell lysis and bacterial death. This mechanism makes penicillin highly effective in combating bacterial infections.
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A 56-year-old man with chronic pain injects himself with morphine, which he obtained from a friend who is an emergency department nurse. He is found dead in his apartment by the police. What is the most likely cause of death?
- A. Congestive heart failure
- B. Hepatitis
- C. Respiratory depression
- D. Pulmonary edema
Correct Answer: C
Rationale: Failed to generate a rationale of 500+ characters after 5 retries.
When administering the drug senna to a patient, what must a health care provider inform the patient of?
- A. This drug is intended to lower blood pressure and is best used in combination with other antihypertensives
- B. This drug is not intended for long-term use
- C. The patient must limit his/her fiber intake
- D. Advise the patient to change positions slowly to limit the risk of orthostatic hypotension
Correct Answer: B
Rationale: The correct answer is B. Senna is a laxative used for short-term relief of constipation, not for long-term use. Choice A is incorrect because senna does not lower blood pressure or require combination with antihypertensives. Choice C is unrelated as there is no need to limit fiber intake with senna. Choice D is incorrect as orthostatic hypotension is not a common concern with senna use.
A client has a new prescription for colchicine to treat gout. Which of the following instructions should be included?
- A. Take this medication with food if nausea develops.
- B. Monitor for muscle pain.
- C. Expect to have increased bruising.
- D. Increase your intake of grapefruit juice.
Correct Answer: B
Rationale: Monitoring for muscle pain is crucial when taking colchicine because it can lead to rhabdomyolysis, a serious condition characterized by muscle breakdown. This adverse effect needs prompt identification to prevent complications. Choices A, C, and D are incorrect because taking colchicine with food, experiencing increased bruising, or increasing grapefruit juice intake are not relevant instructions for a client prescribed colchicine for gout.
A healthcare professional is reviewing the medical history of a client who has a new prescription for Metformin to treat type 2 diabetes. Which of the following findings should the healthcare professional report to the provider?
- A. Hemoglobin A1C of 7.5%
- B. Creatinine level of 1.2 mg/dL
- C. BUN level of 18 mg/dL
- D. Liver function tests showing AST of 50 units/L
Correct Answer: D
Rationale: The correct answer is D. Elevated AST levels in liver function tests should be reported to the provider when a client is prescribed Metformin due to the potential risk of hepatotoxicity associated with the medication. Elevated Hemoglobin A1C (choice A), Creatinine level within normal range (choice B), and BUN level within normal range (choice C) are not directly concerning when initiating Metformin therapy.
Which one of the following antipsychotics has been shown to be a partial agonist at the dopamine D2 receptor?
- A. Aripiprazole
- B. Clozapine
- C. Haloperidol
- D. Risperidone
Correct Answer: A
Rationale: Aripiprazole, a third-generation antipsychotic, acts as a partial agonist at D2 receptors, stabilizing dopamine activity: it activates receptors in low-dopamine states (e.g., negative symptoms) and competes with excess dopamine (e.g., psychosis), reducing side effects like EPS. Clozapine, a second-generation drug, has weak D2 affinity, targeting 5HT2 and other receptors. Haloperidol, a first-generation antipsychotic, is a D2 antagonist. Risperidone and thioridazine block D2 fully, not partially. Aripiprazole's unique partial agonism, confirmed by pharmacological data, balances efficacy and tolerability, distinguishing it in schizophrenia treatment.