WK 1: Cellular injury Flashcards
A 48-year-old woman has a malignant lymphoma involving lymph nodes in the para-aortic region. She is treated with a chemotherapeutic agent which results in the loss of neoplastic cells through fragmentation of individual cell nuclei and cytoplasm. Over the next 2 months, the lymphoma decreases in size, as documented on abdominal CT scans. By which of the following mechanisms has her neoplasm primarily responded to therapy?
A Coagulative necrosis
B Mitochondrial poisoning
C Phagocytosis
D Acute inflammation
E Apoptosis
(E) CORRECT. The induction of individual cell death occurs in the process of apoptosis. The drug effect is targeted primarily at the neoplastic cells, not normal cells.
A 53-year-old man has had severe chest pain for the past 6 hours. On physical examination he is afebrile, but has tachycardia. Laboratory studies show a serum troponin I of 10 ng/mL. A coronary angiogram is performed emergently and reveals >90% occlusion of the anterior interventricular (left anterior descending) artery. In this setting, an irreversible injury to myocardial fibers will have occurred when which of the following cellular changes occurs?
A Glycogen stores are depleted
B Cytoplasmic sodium increases
C Nuclei undergo karyorrhexis
D Intracellular pH diminishes
E Blebs form on cell membranes
(C) CORRECT. Chromatin clumping is reversible, but dissolution of the entire nucleus is not, and when the nucleus is lost, the cell will die. An acute coronary syndrome with myocardial infarction is described here.
