Blinatumomab, a bispecific T-cell engaging molecule, is active against which CD antigen that is expressed on B-lymphoblasts?
- A. CD10
- B. CD15
- C. CD19
- D. CD20
Correct Answer: C
Rationale: Step-by-step rationale:
1. Blinatumomab is a bispecific molecule designed to engage T-cells to target B-lymphoblasts.
2. It targets CD19, a B-cell-specific antigen expressed on B-lymphoblasts.
3. Engagement of T-cells via CD19 leads to targeted killing of B-lymphoblasts.
4. CD10, CD15, and CD20 are not specific to B-cells, making them incorrect choices.
Summary:
The correct answer is C (CD19) because blinatumomab's mechanism of action specifically targets B-lymphoblasts via CD19. Choices A, B, and D are incorrect as they do not have the same specificity for B-cells as CD19 does.
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Haemolytic anemia is not produced by:
- A. penicillin
- B. lithium
- C. Quinidine
- D. methyldopa
Correct Answer: B
Rationale: The correct answer is B: lithium. Lithium does not cause hemolytic anemia because it does not affect red blood cell destruction. Penicillin (A), Quinidine (C), and Methyldopa (D) are known to cause hemolytic anemia by various mechanisms, such as immune-mediated destruction or oxidative damage to red blood cells. In contrast, lithium's mechanism of action does not involve direct harm to red blood cells, making it the correct choice in this scenario.
A patient with pancytopenia has a bone marrow aspiration from the left posterior iliac crest. Which action would be important for the nurse to take after the procedure?
- A. Elevate the head of the bed to 45 degrees.
- B. Apply a sterile 2-inch gauze dressing to the site.
- C. Use a half-inch sterile gauze to pack the wound.
- D. Have the patient lie on the left side for 1 hour.
Correct Answer: D
Rationale: The correct answer is D. Having the patient lie on the left side for 1 hour after a bone marrow aspiration helps to prevent bleeding by applying pressure to the site. This position helps to promote clotting and reduces the risk of hematoma formation. Elevating the head of the bed (choice A) is not necessary for this procedure. Applying a sterile 2-inch gauze dressing (choice B) is important but does not address the immediate post-procedure care. Using a half-inch sterile gauze to pack the wound (choice C) is not recommended as it may disrupt the clotting process.
A nurse is caring for a client who recently started alteplase therapy. The nurse should monitor the client for which of the following adverse effects?
- A. Bronchodilation
- B. Headache
- C. Edema
- D. Hypertension
Correct Answer: B
Rationale: The correct answer is B: Headache. Alteplase is a thrombolytic medication that can cause cerebral bleeding, leading to headaches. Monitoring for headaches is crucial as it can indicate a serious adverse effect. Bronchodilation (A) is not associated with alteplase therapy. Edema (C) is not a common adverse effect of alteplase. Hypertension (D) is a potential adverse effect, but it is not as specific or common as headaches in this context.
Assuming that adherence has been excellent, which of the following should have returned to normal 6 weeks following appropriate oral iron treatment for a child with severe dietary iron deficiency (hemoglobin [Hgb] 5.0 g/dL and mean corpuscular volume [MCV] 48 fL at the beginning of therapy)?
- A. Hgb concentration
- B. MCV
- C. Red cell distribution width
- D. Peripheral blood smear
Correct Answer: A
Rationale: Rationale for Correct Answer (A): Hgb concentration reflects the amount of hemoglobin in the blood, which is directly affected by iron levels. After 6 weeks of appropriate oral iron treatment, the child's severe iron deficiency should have improved, leading to an increase in Hgb concentration back to normal levels.
Explanation of Incorrect Choices:
B: MCV measures the size of red blood cells, which is affected by iron deficiency anemia. However, it may take longer than 6 weeks for MCV to return to normal.
C: Red cell distribution width indicates the variation in red blood cell sizes and is not directly related to iron levels. It may not necessarily return to normal within 6 weeks.
D: Peripheral blood smear provides information on the morphology of red blood cells but does not directly reflect iron levels. It may not show significant changes within 6 weeks of iron treatment.
Presence of an --jaundice --splenomegaly with increase MCH is seen in:
- A. liver cirrhosis
- B. th.major
- C. PNH
- D. herditary spherocytosis
Correct Answer: D
Rationale: The correct answer is D, hereditary spherocytosis. In this condition, the presence of jaundice and splenomegaly is due to the destruction of red blood cells by the spleen, leading to increased MCH. In liver cirrhosis (choice A), jaundice is due to impaired liver function. Thalassemia major (choice B) presents with severe anemia, not jaundice. Paroxysmal nocturnal hemoglobinuria (choice C) is characterized by hemolytic anemia and not typically associated with splenomegaly and jaundice. Therefore, the presence of jaundice, splenomegaly, and increased MCH points towards hereditary spherocytosis.