What are the ingredients in a PTT?

Correct Answer: A

Rationale: Step-by-step rationale: 1. Plasma is the liquid portion of blood. 2. Phospholipid is a component of platelet membrane needed for coagulation. 3. Calcium is required for the activation of coagulation factors. Therefore, the correct answer is A. Summary: B: Thromboplastin is not an ingredient in PTT. C: Thromboplastin is not part of PTT. D: Thrombin is a product of the coagulation cascade, not an ingredient in PTT.

Correct Answer: C

Rationale: The correct answer is C: Rhodnius prolixus. This insect is a vector for Trypanosoma cruzi, causing Chagas disease. Palpebral edema, lymphadenopathy, and megaesophagus are common manifestations. Glossina morsitans transmits African Trypanosomiasis (sleeping sickness) with different symptoms. Ixodes scapularis transmits Lyme disease. Simulium damnosum transmits Onchocerciasis (river blindness). Thus, Rhodnius prolixus is the correct vector based on the provided symptoms.

Correct Answer: B

Rationale: The correct answer is B: Glutathione reduction. NADPH generated from the pentose phosphate pathway in RBCs is crucial for maintaining reduced glutathione levels, which helps protect cells from oxidative damage. Glutathione is an important antioxidant in cells that helps neutralize harmful reactive oxygen species. This process is essential for the protection of RBCs from oxidative stress and maintains their structural integrity. A: Fatty acid synthesis - NADPH is indeed required for fatty acid synthesis, but in RBCs, the primary role of NADPH is in maintaining redox balance rather than fatty acid synthesis. C: ATP formation - NADPH is not directly involved in ATP formation, as ATP is mainly produced through processes like glycolysis and oxidative phosphorylation. D: Oxygen radical removal - While NADPH is involved in reducing oxidative stress, its primary role in RBCs is to maintain glutathione levels for antioxidant defense rather than directly removing oxygen radicals.

Correct Answer: C

Rationale: Schistocytes are fragmented red blood cells formed due to mechanical trauma in the circulation. In the context of microangiopathic hemolytic anemia (MAHA), such as in thrombotic thrombocytopenic purpura or hemolytic uremic syndrome, schistocytes are commonly seen due to the presence of microthrombi in small vessels. This mechanical destruction of red blood cells leads to the characteristic appearance of schistocytes on peripheral blood smear. Therefore, the correct answer is C. Sickle cell trait (choice A) and thalassemia (choice B) do not typically present with schistocytes. In immune thrombocytopenic purpura (ITP) (choice D), the destruction of platelets by autoantibodies does not typically cause schistocytes formation.

Correct Answer: A

Rationale: The correct answer is A: Phlebotomus species. Visceral leishmaniasis is transmitted by sandflies of the genus Phlebotomus in Asia. These sandflies are the main vectors for the parasite that causes the disease. Phlebotomus species are known to transmit Leishmania donovani, the causative agent of visceral leishmaniasis. Lutzomyia species (B) are primarily found in the Americas and are more commonly associated with cutaneous leishmaniasis. Anopheles species (C) are known vectors for malaria, not visceral leishmaniasis. Mansonia species (D) are associated with transmitting various viruses, not Leishmania parasites. Therefore, the correct answer is A as Phlebotomus species are the main vectors of visceral leishmaniasis in Asia.