Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

[Q]: Context: This study was designed to investigate the effects of simvastatin in a rat model of acute myocardial infarction.', 'Male Wistar rats were anesthetized (thiopentone sodium 120 mg/kg). After a thoracotomy, the left-anterior-descending coronary artery (LAD) was occluded (for 25 min) and reperfused (for 120 min). Area at risk (AR) was determined with Evans Blue dye and infarct size after staining of the area at risk with nitroblue tetrazolium.', 'In rats, which received the vehicle for simvastatin (10% DMSO, 1 ml/kg i.v. at 1 h prior to the occlusion of the LAD), occlusion of the LAD for 25 min followed by reperfusion for 2 hours resulted in an infarct size of 54 +/- 4% (n=7) of the AR. When compared with vehicle, administration of simvastatin (1 mg/kg i.v. bolus administration at 1 h prior to the onset of myocardial ischemia) caused a significant reduction in myocardial infarct size of 39%. LAD-occlusion and reperfusion caused a progressive fall in mean arterial blood pressure (when compared with sham-operated animals). Simvastatin had no significant effect on blood pressure.
Answer: The result indicates that simvastatin, an inhibitor of HMG-CoA reductase and a ligand of PPAR-a and PPAR-g, reduces the tissue necrosis associated with acute myocardial infarction. We propose that statins may be useful in conditions associated with ischemia-reperfusion of the heart and other organs.
[A]: Does simvastatin reduce infarct size in a model of acute myocardial ischemia and reperfusion in the rat?


[Q]: Context: Molecular staging of sentinel lymph nodes (SLNs) may identify patients who are node-negative by standard microscopic staging but are at increased risk for regional nodal recurrence; such patients may benefit from completion lymph node dissection (CLND).', 'In a multicenter, randomized clinical trial, patients with tumor-negative SLNs by standard pathology (hematoxylin and eosin [H and E] serial sections and immunohistochemistry [IHC]) underwent reverse transcriptase polymerase chain reaction (PCR) analysis of SLNs for melanoma-specific mRNA. Microscopically negative/PCR+ patients were randomized to observation, CLND, or CLND with high-dose interferon (HDI). For this post-hoc analysis, clinicopathologic features and survival outcomes, including overall survival (OS) and disease-free survival (DFS), were compared between PCR+ patients who underwent CLND vs observation. Microscopic and molecular node-negative (PCR-) patients were included for comparison.', 'A total of 556 patients were PCR+: 180 underwent observation, and 376 underwent CLND. An additional 908 PCR- patients were observed. Median follow-up was 72 months. Disease-free survival (DFS) was significantly better for PCR+ patients who underwent CLND compared with observation (p\xa0= 0.0218). No statistically significant differences in OS or distant disease-free survival (DDFS) were seen. Regional lymph node recurrence-free survival (LNRFS) was improved in PCR+ patients with CLND compared to observation (p\xa0=\xa00.0065). The PCR+ patients in the observation group had the worst DFS; those with CLND had similar DFS to that in the PCR- group (p\xa0= 0.9044).
Answer: Patients with microscopically negative/PCR+ SLN have an increased risk of nodal recurrence that was mitigated by CLND. Although CLND did not affect OS, these data suggest that molecular detection of melanoma-specific mRNA in the SLN predicts a greater risk of nodal recurrence and deserves further study.
[A]: Does molecular Staging of Sentinel Lymph Nodes identify Melanoma Patients at Increased Risk of Nodal Recurrence?


[Q]: Context: The prognostic significance of pathological Q waves appearing in the acute phase of myocardial infarction has not been determined. We investigated whether new Q waves on the presenting electrocardiogram of patients with acute ST-segment elevation were independently associated with a worse outcome after a first myocardial infarction.', 'The presence or absence of new Q waves on the presenting electrocardiogram was assessed in 481 patients who presented within 4 h of symptom onset and were randomized to receive either captopril or placebo within 2 h of streptokinase therapy for myocardial infarction. Ventriculography was performed at 22+/-6 days and mortality status was obtained at a median follow-up of 5.6 years. New Q waves were associated with a lower ejection fraction (51+/-13% vs 61+/-12%, P<0.0001), a larger end-systolic volume index (37 ml vs 28 ml, P<0.001), and increased cardiac mortality at 30 days (7% vs 2%, P=0.01) and at follow-up (17% vs 7%, P=0.002). On multivariate analysis, age (P<0.01), new Q waves at presentation (P<0.01) and a history of angina (P=0.046) were independent predictors of cardiac mortality, whereas randomization to captopril and the time from symptom onset to streptokinase administration were not.
Answer: New Q waves at presentation are independently associated with a worse outcome after a first myocardial infarction. The presence of new Q waves on the presenting electrocardiogram allows very early identification of patients at risk of increased cardiac mortality.
[A]:
Do new Q waves on the presenting electrocardiogram independently predict increased cardiac mortality following a first ST-elevation myocardial infarction?