Q- Which of the following markers identifies B lymphocytes in a blood sample treated with different fluorescent-labeled antibodies?
A- CD3
B- CD4
C- CD8
D- CD19
D- CD19- CD19 is a classic marker found on the surface of B lymphocytes. CD3 identifies T cells, while CD4 and CD8 mark helper and cytotoxic T-cell subsets, not B cells.
Q- A patient with a history of diabetes presents with dark bronze skin pigmentation and multiple arthralgias. Which of the following would be detected in a joint aspirate?
A- Copper
B- Hemosiderin
C- Monosodium urate crystals
D- Negatively birefringent particles
B- Hemosiderin- The patient’s “dark bronze” skin and diabetes strongly suggest hereditary hemochromatosis. In hemochromatosis, excess iron is deposited in multiple tissues, including the joints. Joint aspiration may show hemosiderin-laden macrophages due to iron overload. Calcium pyrophosphate crystals (pseudogout) are common in hemochromatosis, but that option is not provided in the list. Monosodium urate crystals and negatively birefringent particles are findings of gout, not hemochromatosis.
Q- Which of the following is characteristic of Alzheimer’s disease?
A- Lewy bodies
B- Negri bodies
C- Neurofibrillary tangles
D- Nuclear atypia
C- Neurofibrillary tangles- Alzheimer’s disease is characterized by neurofibrillary tangles made of hyperphosphorylated tau protein. Lewy bodies are seen in Parkinson disease and Lewy body dementia, Negri bodies in rabies, and nuclear atypia is a general term not specific to Alzheimer’s.
Thanks Dr. Omar for visiting this website. Have a great day.
Thank you very much
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