Nokea
Characteristics of Amfotericin B are following, EXCEPT:
- A. Used for systemic mycosis treatment
- B. Poor absorption from the gastro-intestinal tract
- C. Does not demonstrate nephrotoxicity
- D. Influences the permeability of fungus cell membrane
Correct Answer: C
Rationale: The correct answer is C: "Does not demonstrate nephrotoxicity." Amphotericin B is known for its nephrotoxicity, which can lead to kidney damage. This is a well-documented side effect of the drug. Choices A, B, and D are incorrect because Amphotericin B is indeed used for systemic mycosis treatment, poorly absorbed from the gastrointestinal tract, and influences the permeability of fungus cell membrane, making them true characteristics of the drug.
You may also like to solve these questions
A 10-year-old patient will be started on methylphenidate hydrochloride (Ritalin) therapy. The nurse will perform which essential baseline assessment before this drug is started?
- A. Eye examination
- B. Height and weight
- C. Liver studies
- D. Hearing test
Correct Answer: B
Rationale: The correct answer is B: Height and weight. Before starting methylphenidate therapy in a 10-year-old patient, it is essential to assess height and weight as this medication can affect growth and appetite. Monitoring these parameters at baseline helps establish a reference point for future assessment of treatment effects on growth. Eye examination (A) is important for long-term monitoring but not essential before starting therapy. Liver studies (C) are not typically required before starting methylphenidate therapy. Hearing test (D) is not directly related to starting this medication.
Mechanism of action of cyclosporine A is:
- A. Complement-mediated cytolysis of T lymphocytes
- B. ADCC towards T lymphocytes
- C. Inhibits calcineurin
- D. Compete for Fc receptors with autoantibodies
Correct Answer: C
Rationale: The correct answer is C: Inhibits calcineurin. Cyclosporine A works by inhibiting calcineurin, a protein phosphatase that is crucial for the activation of T cells. By blocking calcineurin, cyclosporine A prevents the production of interleukin-2, a key cytokine involved in T cell activation and proliferation. This ultimately leads to suppression of the immune response.
Choices A, B, and D are incorrect:
A: Complement-mediated cytolysis of T lymphocytes is not the mechanism of action of cyclosporine A.
B: ADCC towards T lymphocytes does not describe how cyclosporine A works.
D: Competing for Fc receptors with autoantibodies is not related to the mechanism of action of cyclosporine A.
Tick the group of antibiotics having an antimalarial effect:
- A. Aminoglycosides
- B. Tetracyclins
- C. Carbapenems
- D. Penicillins
Correct Answer: B
Rationale: Step 1: Tetracyclins are known to have antimalarial properties by inhibiting protein synthesis in Plasmodium species.
Step 2: Aminoglycosides (choice A) primarily target bacteria, not parasites like malaria.
Step 3: Carbapenems (choice C) and Penicillins (choice D) are both beta-lactam antibiotics that have no significant antimalarial effects.
Summary: Tetracyclins are the correct choice as they directly target malaria parasites, while the other options do not possess antimalarial properties.
Methotrexate is:
- A. A purine antagonist
- B. A folic acid antagonist
- C. An antibiotic
- D. An alkylating agent
Correct Answer: B
Rationale: Methotrexate is a folic acid antagonist. It inhibits dihydrofolate reductase, leading to decreased DNA synthesis. This action makes it effective in treating cancer and autoimmune diseases. Purine antagonists target purine synthesis, antibiotics act on bacterial growth, and alkylating agents damage DNA to prevent cell division. Methotrexate's mechanism aligns with folic acid antagonism, making option B the correct choice.
Which of the following drugs most likely caused the adverse effect of dizziness and fainting when standing up rapidly?
- A. Propranolol
- B. Minoxidil
- C. Hydralazine
- D. Prazosin
Correct Answer: D
Rationale: The correct answer is D: Prazosin. Prazosin is an alpha-1 adrenergic blocker that can cause orthostatic hypotension, leading to dizziness and fainting when standing up rapidly. It works by dilating blood vessels, which can cause a sudden drop in blood pressure upon standing. Propranolol (A) is a beta-blocker and can cause dizziness but is less likely to cause orthostatic hypotension. Minoxidil (B) is a vasodilator that can cause rapid heart rate but not typically dizziness upon standing. Hydralazine (C) is a direct vasodilator that can cause reflex tachycardia but is less likely to cause orthostatic hypotension compared to alpha-1 blockers like Prazosin.