Page 111 - Human Bile Acid Metabolism: a Postprandial Perspective

Study Design
The DJBL was delivered and retrieved endoscopically where after subjects were studied and followed up upon as described previously [17]. Here, we report on three visits: 1) within one month prior to implantation (baseline), 2) one week after implantation (week 1), and 3) 24 weeks after implantation, just prior to removal (week 24). Standardized meal tolerance tests were performed. An intravenous cannula was placed for blood sampling. The first sample was drawn after an overnight fast; subsequently a standard liquid meal was consumed (Ensure Plus, Abbott Laboratories, IL; 333 mL, 500 kcal, 20.8 g protein, 67.3 g carbohydrates, and 16.4 g fat), followed by collection of blood samples after 30, 60, 90, 120 and 180 min (BD Vacutainer EDTA tube/EDTA aprotinin tube, BD diagnostics, Erembodegem-Aalst, Belgium). Samples were immediately cooled, centrifuged, and stored at −80 °C until analysis.
Laboratory Analysis
Bile acid concentrations were determined using a UPLC-tandem MS method to
quantify CA, CDCA, DCA and ursodeoxycholic acid (UDCA) in their conjugated 6 and unconjugated forms [18]. FGF19 was measured using an in-house developed
ELISA as published previously [19]. Total bile acids were calculated by adding up
all the individual bile acids measurements.
Ethics
The study was approved by the Medical Ethics Committee of both centers and conducted according to the revised version of the Declaration of Helsinki. Written informed consent was obtained from every subject prior to study participation. Clinical Trial Registration Number: NCT00985114.
Statistical Analysis
Statistical analysis was performed using IBM SPSS Statistics 22 (IBM, Armonk, NY, USA). Data were visually and statistically assessed for normality and logarithmically transformed where appropriate. Area-under-the-curve (AUC) of postprandial plasma levels was calculated using the trapezoidal method; subsequent correction for baseline values yielded the incremental-area-under- the-curve (iAUC). Peak time was defined as the first time point at which maximal concentration was reached. Comparisons between 3 test conditions were made using Friedman’s test to determine significant differences. Individual comparisons
Duodenal-jejunal bypass liner
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