Utilizing functional lumen imaging probe in directing treatment for post-fundoplication dysphagia.

BACKGROUND: Esophagogastric junction obstruction (EGJO) post-fundoplication (PF) is difficult to identify with currently available tests. We aimed to assess the diagnostic accuracy of EGJ opening on functional lumen imaging probe (FLIP) and dilation outcome in FLIP-detected EGJO in PF dysphagia. METHODS: We prospectively collected data on PF patients referred to Esophageal Clinic over 18 months. EGJO diagnosis was made by (a) endoscopist's description of a narrow EGJ/wrap area, (b) appearance of wrap obstruction or contrast/tablet retention on esophagram, or (c) EGJ-distensibility index (DI) < 2.8 mm2/mmHg on real-time FLIP. In patients with EGJO and dysphagia, EGJ dilation was performed to 20 mm, 30 mm, or 35 mm in a stepwise fashion. Outcome was assessed as % dysphagia improvement during phone call or on brief esophageal dysphagia questionnaire (BEDQ) score. RESULTS: Twenty-six patients were included, of whom 17 (65%) had a low EGJ-DI. No patients had a hiatal hernia greater than 3 cm. Dysphagia was the primary symptom in 17/26 (65%). In 85% (κ = 0.677) of cases, EGJ assessment (tight vs. open) was congruent between the combination of endoscopy (n = 26) and esophagram (n = 21) vs. EGJ-DI (n = 26) on FLIP. Follow-up data were available in 11 patients who had dilation based on a low EGJ-DI (4 with 20 mm balloon and 7 with ≥ 30 mm balloon). Overall, the mean % improvement in dysphagia was 60% (95% CI 37.7-82.3%, p = 0.0001). Nine out of 11 patients, including 6 out of 7 undergoing pneumatic dilation, had improvement ≥ 50% in dysphagia (mean % improvement 72.2%; 95% CI 56.1-88.4%, p = 0.0001). CONCLUSIONS AND INFERENCES: Functional lumen imaging probe is an accurate modality for evaluating for EGJ obstruction PF. FLIP may be used to select patients who may benefit from larger diameter dilation.

Colonic Microbiota Encroachment Correlates With Dysglycemia in Humans.

BACKGROUND AND AIMS: Mucoid structures that coat the epithelium play an essential role in keeping the intestinal microbiota at a safe distance from host cells. Encroachment of bacteria into the normally almost-sterile inner mucus layer has been observed in inflammatory bowel disease and in mouse models of colitis. Moreover, such microbiota encroachment has also been observed in mouse models of metabolic syndrome, which are associated low-grade intestinal inflammation. Hence, we investigated if microbiota encroachment might correlate with indices of metabolic syndrome in humans. METHODS: Confocal microscopy was used to measure bacterial-epithelial distance of the closest bacteria per high-powered field in colonic biopsies of all willing participants undergoing cancer screening colonoscopies. RESULTS: We observed that, among all subjects, bacterial-epithelial distance was inversely correlated with body mass index, fasting glucose levels, and hemoglobin A1C. However, this correlation was driven by dysglycemic subjects, irrespective of body mass index, whereas the difference in bacterial-epithelial distance between obese and nonobese subjects was eliminated by removal of dysglycemic subjects. CONCLUSIONS: We conclude that microbiota encroachment is a feature of insulin resistance-associated dysglycemia in humans.

Glial cell line-derived neurotrophic factor enhances neurogenin3 gene expression and beta-cell proliferation in the developing mouse pancreas.

Glial cell line-derived neurotrophic factor (GDNF) is a factor produced by glial cells that is required for the development of the enteric nervous system. In transgenic mice that overexpress GDNF in the pancreas, GDNF has been shown to enhance beta-cell mass and improve glucose control, but the transcriptional and cellular processes involved are not known. In this study we examined the influence of GDNF on the expression of neurogenin3 (Ngn3) and other transcription factors implicated in early beta-cell development, as well as on beta-cell proliferation during embryonic and early postnatal mouse pancreas development. Embryonic day 15.5 (E15.5) mouse pancreatic tissue when exposed to GDNF for 24 h showed higher Ngn3, pancreatic and duodenal homeobox gene 1 (Pdx1), neuroD1/beta(2), paired homeobox gene 4 (Pax4), and insulin mRNA expression than tissue exposed to vehicle only. Transgenic expression of GDNF in mouse pancreata was associated with increased numbers of Ngn3-expressing pancreatic cells and higher beta-cell mass at embryonic day 18 (E18), as well as higher beta-cell proliferation and Pdx1 expression in beta-cells at E18 and postnatal day 1. In the HIT-T15 beta-cell line, GDNF enhanced the expression of Pax6. This response was, however, blocked in the presence of Pdx1 small interfering RNA (siRNA). Chromatin immunoprecipitation studies using the HIT-T15 beta-cell line demonstrated that GDNF can influence Pdx1 gene expression by enhancing the binding of Sox9 and neuroD1/beta(2) to the Pdx1 promoter. Our data provide evidence of a mechanism by which GDNF influences beta-cell development. GDNF could be a potential therapeutic target for the treatment and prevention of diabetes.