approximation to aflatoxin B metabolism and sensitivity in commercial poultry species based on empirical mathematical equations.

Enzyme kinetic parameters for aflatoxin B metabolism have been reported for chicken, quail, turkey and duck, but an integrated model has not been proposed. Both enzyme-catalyzed reactions and spontaneous reactions were modeled in the CellDesigner software and results were adjusted to Hill, Rational and Hoerl models. Results revealed that the higher amount of aflatoxin B epoxide produced in a short lapse of time and a low production of epoxide conjugated to glutathione explains the severe genotoxic effect of aflatoxin B in duck.

The role of endoscopy in the management of GERD.

We recommend that uncomplicated GERD be diagnosed on the basis of typical symptoms without the use of diagnostic testing, including EGD. We recommend EGD for patients who have symptoms suggesting complicated GERD or alarm symptoms. We recommend that EGD not be routinely performed solely for the assessment of extraesophageal GERD symptoms.

Association between circulating levels of sex steroid hormones and Barrett's esophagus in men: a case-control analysis.

Background & Aims: Esophageal adenocarcinoma is believed to result from the progression of gastroesophageal reflux disease to erosive esophagitis and re-epithelialization of the esophagus with a columnar cell population termed Barrett's esophagus (BE). Men develop BE and esophageal adenocarcinoma more frequently than women, yet little is known about the mechanisms of this difference. We assessed whether sex steroid hormones were associated with BE in a male population.