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: To conduct an untargeted, high resolution exploration of metabolic pathways that was altered in association with hepatic steatosis in adolescents.', 'This prospective, case-control study included 39 Hispanic-American, obese adolescents aged 11-17\xa0years evaluated for hepatic steatosis using magnetic resonance spectroscopy. Of these 39 individuals, 30\xa0had hepatic steatosis ≥5% and 9 were matched controls with hepatic steatosis <5%. Fasting plasma samples were analyzed in triplicate using ultra-high resolution metabolomics on a Thermo Fisher Q Exactive mass spectrometry system, coupled with C18 reverse phase liquid chromatography. Differences in plasma metabolites between adolescents with and without nonalcoholic fatty liver disease (NAFLD) were determined by independent t tests and visualized using Manhattan plots. Untargeted pathway analyses using Mummichog were performed among the significant metabolites to identify pathways that were most dysregulated in NAFLD.', 'The metabolomics analysis yielded 9583 metabolites, and 7711 with 80% presence across all samples remained for statistical testing. Of these, 478 metabolites were associated with the presence of NAFLD compared with the matched controls. Pathway analysis revealed that along with lipid metabolism, several major amino acid pathways were dysregulated in NAFLD, with tyrosine metabolism being the most affected.
Answer: Metabolic pathways of several amino acids are significantly disturbed in adolescents with elevated hepatic steatosis. This is a novel finding and suggests that these pathways may be integral in the mechanisms of NAFLD.
[A]: Is amino Acid Metabolism Altered in Adolescents with Nonalcoholic Fatty Liver Disease-An Untargeted , High Resolution Metabolomics Study?


[Q]: Context: Ischemic mitral regurgitation (MR) often persists after restrictive mitral valve annuloplasty, in which case it is associated with worse clinical outcomes. The goal of the present study was to determine whether persistence of MR and/or clinical outcome could be predicted from preoperative analysis of mitral valve configuration.', 'In 51 consecutive patients undergoing restrictive annuloplasty for ischemic MR, posterior leaflet (PL) angle, anterior leaflet angle, coaptation distance, and tenting area were quantified by echocardiography before surgery (6+/-3 days), and MR severity was assessed before and early after surgery (9+/-4 days). Postoperatively, persistence of mild to moderate MR (vena contracta > 3 mm) was observed in 11 (22%) of the patients. The best predictor of postoperative persistence of MR was a PL angle > or = 45 degrees (sensitivity 100%, specificity 97%, positive predictive value 92%, negative predictive value 100%). Patients with persistent MR had markedly lower 3-year event-free survival (26+/-20%) compared with those with nonpersistent MR (75+/-12%, P=0.01). Preoperative presence of a PL angle > or = 45 degrees also was associated with a markedly lower 3-year event-free survival (22+/-17% versus 76+/-12%; P<0.001).
Answer: In patients undergoing restrictive annuloplasty for ischemic MR, persistence of MR and 3-year event-free survival can accurately be predicted by preoperative analysis of mitral valve configuration. Patients with a PL angle > or = 45 degrees (ie, with high PL restriction) should thus be considered poor candidates for this procedure, and concomitant or alternative procedures should be contemplated.
[A]: Does preoperative posterior leaflet angle accurately predict outcome after restrictive mitral valve annuloplasty for ischemic mitral regurgitation?


[Q]: Context: Atrial fibrillation (AF) and chronic kidney disease (CKD) are closely related. The present study aimed to evaluate the association between estimated glomerular filtration rate (eGFR) and outcomes after cryoballoon catheter ablation for AF.', 'We included a total of 110 patients (64.0±10.1 years, 64% men) with paroxysmal AF who underwent second-generation cryoballoon catheter ablation in this study. Recurrence and change in renal function after ablation were assessed by stratification of eGFR sub-groups.', 'During a mean follow-up period of 9 months, 20 (18%) patients had AF recurrence after the first catheter ablation procedure. Multivariate Cox regression analysis showed that eGFR [hazard ratio (HR) 0.97, 95% confidence interval (CI) 0.93-0.99, p=0.047], non-pulmonary vein (PV) ectopic beats at initial ablation (HR 2.92, 95% CI 1.03-8.27, p=0.043), and history of stroke (HR 7.47, 95% CI 2.30-24.2, p=0.001) were independent predictors of recurrence after the ablation. Among the CKD groups, recurrence was found in 7% (1/15), 12% (9/73), and 46% (10/22) of the eGFR ≥90mL/min/1.73m
Answer: Low eGFR at baseline was an independent predictor of recurrence after cryoballoon ablation for paroxysmal AF. The presence of non-PV ectopic beats was significantly increased in patients with impaired renal function, which might be associated with a poor outcome.
[A]:
Is impaired renal function associated with recurrence after cryoballoon catheter ablation for paroxysmal atrial fibrillation : A potential effect of non-pulmonary vein foci?