A clinical-grade acellular matrix for esophageal replacement.

In pathologies of the esophagus such as esophageal atresia, cancers, and caustic injuries, methods for full thickness esophageal replacement require the sacrifice of healthy intra-abdominal organs such as the stomach and the colon and are associated with high morbidity, mortality, and poor functional results. To overcome these problems, tissue engineering methods are developed to create a substitute with scaffolds and cells. The aim of this study was to develop a simple and safe decellularization process in order to obtain a clinical grade esophageal extracellular matrix. Following the decontamination step, porcine esophagi were decellularized in a bioreactor with sodium dodecyl sulfate and ethylenediaminetetraacetic acid for 3 days and were rinsed with deionized water. DNA was eliminated by a 3-hr DNase treatment. To remove any residual detergent, the matrix was then incubated with an absorbing resin. The resulting porcine esophageal matrix was characterized by the assessment of the efficiency of the decellularization process (DNA quantification), evaluation of sterility and absence of cytotoxicity, and its composition and biomechanical properties, as well as the possibility to be reseeded with mesenchymal stem cells. Complete decellularization with the preservation of the general structure, composition, and biomechanical properties of the native esophageal matrix was obtained. Sterility was maintained throughout the process, and the matrix showed no cytotoxicity. The resulting matrix met clinical grade criteria and was successfully reseeded with mesenchymal stem cells..

Roux-en-Y gastric bypass for the treatment of severe complications after omega-loop gastric bypass.

BACKGROUND: Omega-loop gastric bypass (OLGB) may be associated with severe complications, including anastomotic leak, refractory ulcer or stenosis, undernutrition, and disabling digestive disorders (chronic diarrhea, steatorrhea, bile reflux, and vomiting). OLGB conversion to Roux-en-Y gastric bypass (RYGB) was suggested to treat these complications. OBJECTIVES: To evaluate the efficacy and risk of severe complications after OLGB conversion to RYGB. SETTING: University hospital. METHODS: Retrospective analysis between October 2011 and June 2016. RESULTS: Seventeen patients underwent OLGB conversion to RYGB. Fourteen patients (82%) presented at least 1 disabling digestive disorder. Before conversion, 10 patients (58.8%) received nutritional support for undernutrition. There was no postoperative mortality. Seven patients (41.1%) developed major adverse events (<90 d). At conversion, the average weight, body mass index, and percent of excess weight loss for the population without undernutrition (n = 7) were 103.7±24 kg, 38.7±6.8 kg/m², and 37%±33%, respectively. These values were 85±18.3 kg, 30.6±4.7 kg/m², and 73.3%±21.5%, respectively, at 2 years. In patients with undernutrition (n = 10), the average weight, body mass index, and percent of excess weight loss were 52.2±16.5 kg, 18.7±5.9 kg/m², and 149.3%±46.5%, respectively, before nutritional support and 58.9±14.7 kg, 21.1±5.2 kg/m², and 132.7%±39.1%, respectively, at revisional surgery. At 2 years the values were 71±5.6 kg, 24.3±2.2 kg/m², and 104.6%±15.2%, respectively. The patients experienced significant improvements in hypoalbuminemia, anemia, and vitamin/trace element deficiencies. The disabling digestive disorders resolved in 85% of patients. CONCLUSION: The conversion of OLGB to RYGB for severe complications allows for weight correction in patients with undernutrition, reduces disabling digestive disorders, and improves the nutritional status of patients. However, the conversion is associated with high morbidity.