An Imaging Study Measuring the Form and Structure of the Layers of the Duodenum in Patients with and without Type 2 Diabetes


About this study

This observational study is conducted to determine how the duodenal layer thicknesses (mucosa, submucosa, and muscularis) vary with several factors in patients with and without type 2 diabetes.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria

  • Patient is already scheduled for upper endoscopy with ultrasound or OCT, such as those with Barrett's esophagus
  • Patient is willing to sign an informed consent form

Exclusion Criteria

  • Patient is not a candidate for endoscopy, EUS, or OCT, such as those with strictures, inflammatory disease or previous anastomosis of the esophagus or duodenum

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Jacksonville, Fla.

Mayo Clinic principal investigator

Victoria Gomez, M.D.

Closed for enrollment

More information


  • Enteroendocrine cells are solitary epithelial cells scattered throughout the gastrointestinal tract and produce various types of hormones, constituting one of the largest endocrine systems in the body. The study of these rare epithelial cells has been hampered by the difficulty in isolating them because of the lack of specific cell surface markers. Here, we report that enteroendocrine cells selectively express a tight junction membrane protein, claudin-4 (Cld4), and are efficiently isolated with the use of an antibody specific for the Cld4 extracellular domain and flow cytometry. Sorted Cld4+ epithelial cells in the small intestine exclusively expressed a chromogranin A gene (Chga) and other enteroendocrine cell-related genes (Ffar1, Ffar4, Gpr119), and the population was divided into two subpopulations based on the activity of binding to Ulex europaeus agglutinin-1 (UEA-1). A Cld4+UEA-1- cell population almost exclusively expressed glucose-dependent insulinotropic polypeptide gene (Gip), thus representing K cells, whereas a Cld4+UEA-1+ cell population expressed other gut hormone genes, including glucagon-like peptide 1 (Gcg), pancreatic polypeptide-like peptide with N-terminal tyrosine amide (Pyy), cholecystokinin (Cck), secretin (Sct), and tryptophan hydroxylase 1 (Tph1). In addition, we found that orally administered luminal antigens were taken up by the solitary Cld4+ cells in the small intestinal villi, raising the possibility that enteroendocrine cells might also play a role in initiation of mucosal immunity. Our results provide a useful tool for the cellular and functional characterization of enteroendocrine cells. Read More on PubMed
  • Incretins are hormones released by enteroendocrine cells in response to meals, depending upon absorption of nutrients. The present study aimed to elucidate the mechanisms through which a high-fat diet (HFD) induces insulin resistance and insulin hypersecretion by focusing on the effects on enteroendocrine cells, especially those secreting glucose-dependent insulinotropic polypeptide (GIP). Read More on PubMed
  • The prevalence of obesity-induced type 2 diabetes mellitus is increasing worldwide. The objective of this review and meta-analysis is to determine the impact of bariatric surgery on type 2 diabetes in association with the procedure performed and the weight reduction achieved. Read More on PubMed
  • Optical coherence tomography (OCT) has demonstrated the microscopic structure of the gastrointestinal (GI) tract mucosa and submucosa in vitro. We evaluated a prototype OCT system and assessed the feasibility of OCT in the human GI tract. Read More on PubMed
  • Thirty-eight consecutive patients underwent endoscopic ultrasound-guided fine-needle aspiration. Of 46 lesions, 34 were extraluminal (12 pancreatic masses, 8 periesophageal nodes, 6 celiac nodes, 2 pericolonic masses, 1 mediastinal mass, 1 perigastric mass, 1 liver, 1 periduodenal node, 1 perirectal mass, 1 perirectal node) and 12 were submucosal (8 gastric, 3 duodenal, 1 esophageal). One hundred sixty-three passes were made, with an average of 3.5 passes per lesion and 4.3 passes per patient (range, 1 to 8). Adequate specimens were obtained from 91% of targeted lesions. The overall diagnostic accuracy was 87%. In patients with malignant lesions, sensitivity was 91% and specificity 100%. Celiac nodes were successfully sampled and diagnostic in 5 of 6 (83%) patients. No complications occurred. Using this technique, an initial tissue diagnosis of malignancy was made in 66% of cancer patients without a previous diagnosis and the preoperative stage was changed in 44% of cancer patients. The additional information gained by this modality directly influenced the decision not to perform surgery in 26% of patients with a primary malignancy. Endoscopic ultrasound-guided fine-needle aspiration is feasible and can be safely used to evaluate submucosal and extraluminal lesions in both the upper and lower gastrointestinal tract with a high degree of diagnostic accuracy. Read More on PubMed
  • Eighty-eight patients with carcinoma of the esophagus (N = 44), stomach (N = 41), and duodenum (N = 3) who underwent surgery were pre-operatively examined by endoscopic ultrasonography (EUS). The ability of EUS to accurately predict the T stage and the N stage was 82% and 70% for esophageal carcinoma, 71% and 75% for gastric cancer, and 100% and 66% for duodenal malignancy. In esophageal carcinoma, the accuracy of T staging was only slightly lower in cases with non-traversable tumor stenoses (77%) compared with traversable carcinomas (84%). This was probably due to the fact that all non-traversable tumors were either in stage T3 or T4. The accuracy of EUS in predicting the stages T1 to T3, which correspond to R0 resectability (no macroscopic or microscopic tumor remains), was 92% for adenocarcinoma of the distal esophagus and 85% for gastric cancer. However, in squamous cell carcinoma of the esophagus, R0 resection was possible in only 66% of all cases, whereas EUS predicted an 84% R0 resection rate. In adenocarcinoma of the distal esophagus and stomach, EUS prediction of stages T1 to T3 correlated well with the actual rate of R0 resection. These results show that EUS is a reliable diagnostic method for the local staging of upper gastrointestinal cancer. Its impact on treatment and hence on prognosis of patients with these malignancies has yet to be determined. Read More on PubMed
  • Microscopic changes in duodenal biopsy specimens from 16 elderly patients with small-bowel bacterial overgrowth were studied before and after cyclical courses of antibiotic treatment, using computer-aided morphometry measurements as well as visual assessment. Twenty-three subjects in the same age group with no evidence of intestinal disorder were studied as controls. Mean villus height was significantly reduced in the pre-treatment study compared to the post-treatment measurements and those in controls. Similar significant differences were found in mean crypt depth and total mucosal thickness. The mean intra-epithelial lymphocyte count was raised before treatment and fell after treatment to a level similar to that of the controls. The mean lymphocyte count in the peripheral blood rose significantly after treatment. This study provides objective evidence of microscopic structural changes in the bacterial overgrowth syndrome in old age. The return to normality after antibiotic treatment suggests that these changes are directly attributable to the presence of bacteria in the gut lumen. Read More on PubMed
  • The appearance of the small intestinal mucosa in cow's milk protein intolerance (CMPI) was studied using quantitative morphometry. The parameters under study were the numbers of eosinophil cells in the lamina propria and epithelium, villous height, crypt zone depth, villous height/crypt zone depth ratio, and total mucosal thickness. Tracings of whole sections were analysed using a suitably programmed minicomputer linked to a digitising table. Small bowel biopsy specimens from children with untreated CMPI, from children before and after clinical relapse on cow's milk challenges, and from children with resolved CMPI were compared to each other, to those from control infants, and to those from children with coeliac disease. No change of diagnostic significance could be found in the number of lamina propria eosinophil cells, but levels of intraepithelial eosinophils were significantly increased following cow's milk challenge. Quantification of mucosal dimensions confirmed the presence of a cow's milk-sensitive enteropathy and established the finding of a thin mucosa in CMPI regardless of clinical disease activity. Mucosal thickness was not different from control values following resolution of the disease. In coeliac disease mucosal thickness was significantly greater than in CMPI (apart from young children with untreated coeliac disease whose mucosa was not thicker than that of children with untreated CMPI) but not different from control values. It is suggested that in CMPI there is a limitation in the capacity of crypt cells to compensate for the loss of villous epithelium. Read More on PubMed

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