General Pathology USMLE Step 1 Practice Question
A 58-year-old man with history of smoking presents with acute chest pain, diaphoresis, and dyspnea. Vital signs show BP 142/88 mmHg, HR 102 bpm, RR 18, temp 37.2°C, SpO2 98% on room air. ECG demonstrates ST-elevation in leads II, III, aVF. Troponin I is elevated at 8.2 ng/mL. Two weeks post-MI, echocardiography reveals a noncontractile fibrous scar in the inferior wall without ventricular rupture. Which mediator most strongly promotes fibroblast chemotaxis and collagen deposition during cardiac wound repair?
Answer choices
- AC3a
- BNitric oxide
- CTransforming growth factor betaCorrect answer
- DIL 8
- EHistamine
- FPlatelet-derived growth factor (PDGF) binding PDGFR on fibroblasts
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