Given a passage, 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.

It has already been demonstrated that the rat esophagus produces retinoic acid from retinol. In this study, this process is further characterized and the effect of acetaldehyde examined to elucidate the possible mechanisms behind the epidemiological evidence that the incidence of esophageal cancer is higher in alcoholics.', 'Rat esophageal samples were incubated with all-trans retinal and newly formed all-trans retinoic acid (ATRA) was quantified using high-performance liquid chromatography (HPLC). Furthermore, beta-nicotinamide adenine dinucleotide (NAD)-dependent acetaldehyde oxidation by the rat esophagus was examined by tracing NAD reduction using a spectrophotometer.', 'Rat esophageal samples produced ATRA from all-trans retinal in a NAD-dependent manner and the potential was significantly attenuated by phenetyl isothiocynate, an ALDH inhibitor, or acetaldehyde depending on the concentration used. Rat esophageal samples also oxidized acetaldehyde of various concentrations NAD dependently. The ATRA formation potential that was temporarily inhibited by acetaldehyde was recovered to the control level by dialysis when the specimen was incubated with up to 50 microM of acetaldehyde.
Does acetaldehyde inhibit the formation of retinoic acid from retinal in the rat esophagus?

This study was designed to determine the relevance of a proposed classification for advanced heart failure (HF). Profiles based on clinical assessment of congestion and perfusion at the time of hospitalization were compared with subsequent outcomes.', 'Optimal design of therapy and trials for advanced HF remains limited by the lack of simple clinical profiles to characterize patients.', "Prospective analysis was performed for 452 patients admitted to the cardiomyopathy service at the Brigham and Women's Hospital with a diagnosis of HF. Patients were classified by clinical assessment into four profiles: profile A, patients with no evidence of congestion or hypoperfusion (dry-warm, n = 123); profile B, congestion with adequate perfusion (wet-warm, n = 222); profile C, congestion and hypoperfusion (wet-cold, n = 91); and profile L, hypoperfusion without congestion (dry-cold, n = 16). Other standard predictors of outcome were included and patients were followed for the end points of death (n = 117) and death or urgent transplantation (n = 137) at one year.", 'Survival analysis showed that clinical profiles predict outcomes in HF. Profiles B and C increase the risk of death plus urgent transplantation by univariate (hazard ratio [HR] 1.83, p = 0.02) and multivariate analyses (HR 2.48, p = 0.003). Moreover, clinical profiles add prognostic information even when limited to patients with New York Heart Association (NYHA) class III/IV symptoms (profile B: HR 2.23, p = 0.026; profile C: HR 2.73, p = 0.009).
Does clinical assessment identify hemodynamic profiles that predict outcomes in patients admitted with heart failure?

Ulcerative colitis (UC) is a chronic inflammatory intestinal disease. It is necessary to find out new effective drugs for UC. In our study epicatechin extracted from grape seed by our institute for the first time could treat UC effectively. Then anti-UC mechanisms of epicatechin were elucidated in vivo and in vitro.', 'Dextran sulfate sodium (DSS)-induced acute UC mice model was used to evaluate the activity of epicatechin and its properties against UC. Then its anti-inflammatory and antioxidant effects were evaluated as follows: the concentrations of TNF-α and IL-6 in the colon supernatants were determined by ELISA. NO and MPO were assayed by Griess method and commercial kit respectively. NF-κB were determined by NF-κB-Dependent Reporter Gene Expression Assay and Western Blotting respectively. Antioxidant factors such as SOD, MDA, GSH-Px and CAT were also measured in colon tissues and cell supernatant stimulated by LPS respectively.', 'In C57BL/6J mice model with DSS-induced UC, epicatechin was able to decrease the disease activity index and colon macroscopic damage index scores, reduce body weight loss, and significantly relieve colon contracture and crypt damage. TNF-α, IL-6, NO, MPO and MDA were reduced in the mice administered epicatechin, whereas antioxidant enzymes showed increased activity in epicatechin-treated mice and cell line respectively. Furthermore, inhibition effect on NF-κB activation by epicatechin were demonstrated in vivo and in vitro.

Is the protective effect of epicatechin on experimental ulcerative colitis in mice mediated by increasing antioxidation and by the inhibition of NF-κB pathway?