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Roux-en-Y gastric bypass (RYGB) is an effective treatment for obesity. Importantly, weight loss following RYGB is thought to result in part from changes in brain-mediated regulation of appetite and food intake. Dopamine (DA) within the dorsal striatum plays an important role in feeding behavior; we therefore hypothesized that RYGB alters DA homeostasis in this subcortical region. In the current study, obese RYGB-operated mice consumed significantly less of a high-fat diet, weighed less by the end of the study, and exhibited lower adiposity than obese sham-operated mice. Interestingly, both RYGB and caloric restriction (pair feeding) resulted in elevated DA and reduced norepinephrine (NE) tissue levels compared with ad libitum fed sham animals. Consequently, the ratio of NE to DA, a measure of DA turnover, was significantly reduced in both of these groups. The RYGB mice additionally exhibited a significant increase in phosphorylation of tyrosine hydroxylase at position Ser31, a key regulatory site of DA synthesis. This increase was associated with augmented expression of extracellular-signal-regulated kinases ERK1/2, the kinase targeting Ser31. Additionally, RYGB has been shown in animal models and humans to improve insulin sensitivity and glycemic control. Curiously, we noted a significant increase in the expression of insulin receptor-β in RYGB animals in striatum (a glucosensing brain region) compared to sham ad libitum fed mice. These data demonstrate that RYGB surgery is associated with altered monoamine homeostasis at the level of the dorsal striatum, thus providing a critical foundation for future studies exploring central mechanisms of weight loss in RYGB.
OBJECTIVES - We sought to determine: (1) if early weight regain between 1 and 2 years after Roux-en-Y gastric bypass (RYGB) is associated with worsened hepatic and peripheral insulin sensitivity, and (2) if preoperative levels of ghrelin and leptin are associated with early weight regain after RYGB.
METHODS - Hepatic and peripheral insulin sensitivity and ghrelin and leptin plasma levels were assessed longitudinally in 45 subjects before RYGB and at 1 month, 6 months, 1 year, and 2 years postoperatively. Weight regain was defined as ≥5% increase in body weight between 1 and 2 years after RYGB.
RESULTS - Weight regain occurred in 33% of subjects, with an average increase in body weight of 10 ± 5% (8.5 ± 3.3 kg). Weight regain was not associated with worsening of peripheral or hepatic insulin sensitivity. Subjects with weight regain after RYGB had higher preoperative and postoperative levels of ghrelin compared to those who maintained or lost weight during this time. Conversely, the trajectories of leptin levels corresponded with the trajectories of fat mass in both groups.
CONCLUSIONS - Early weight regain after RYGB is not associated with a reversal of improvements in insulin sensitivity. Higher preoperative ghrelin levels might identify patients that are more susceptible to weight regain after RYGB.
Copyright © 2014 The Obesity Society.
The indications for duct-to-duct (DD) biliary reconstruction in living donor liver transplantation (LDLT) for small children are still controversial. In this study, the feasibility of DD biliary reconstruction versus Roux-en-Y (RY) biliary reconstruction was investigated in terms of long-term outcomes. Fifty-six children who consecutively underwent LDLT with a weight less than or equal to 10.0 kg were enrolled. Biliary reconstruction was performed in a DD fashion for 20 patients and in an RY fashion for 36 patients. During a minimum follow-up of 2 years, the incidence of biliary strictures was 5.0% in the DD group and 11.1% in the RY group. Cholangitis during the posttransplant period was observed in the RY group only. There were no deaths related to biliary problems. This study shows that DD reconstruction in LDLT for small children (weighing 10.0 kg or less) is a feasible option for biliary reconstruction.
© 2014 American Association for the Study of Liver Diseases.
We report the complex case of a 12-month-old girl with stage IV hepatoblastoma accompanied by thrombosis and cavernous transformation of the portal vein. After neoadjuvant chemotherapy, she underwent right hepatectomy, which was complicated by iatrogenic injury of her left hepatic duct, and subsequently developed a postoperative biloma and chronic biliocutaneous fistula. Concomitant with multiple percutaneous interventions to manage the biloma nonoperatively while the child completed her adjuvant chemotherapy, she progressed to develop chronic malnutrition, jaundice, and failure to thrive. Once therapy was completed and the child was deemed free of disease, she underwent exploratory laparotomy with Roux-en-Y biliary cystenterostomy for definitive management, resulting in resolution of her biliary fistula, jaundice, and marked improvement in her nutritional status. Roux-en-Y biliary cystenterostomy is a unique and efficacious management option in the highly selected patient population with chronic biliary leak refractory to minimally invasive management.
Copyright © 2012 Elsevier Inc. All rights reserved.
Bypass of the foregut following Roux-en-Y gastric bypass (RYGB) surgery results in altered nutrient absorption, which is proposed to underlie the improvement in glucose tolerance and insulin sensitivity. We conducted a prospective crossover study in which a mixed meal was delivered orally before RYGB (gastric) and both orally (jejunal) and by gastrostomy tube (gastric) postoperatively (1 and 6 wk) in nine subjects. Glucose, insulin, and incretin responses were measured, and whole-body insulin sensitivity was estimated with the insulin sensitivity index composite. RYGB resulted in an improved glucose, insulin, and glucagon-like peptide-1 (GLP-1) area under the curve (AUC) in the first 6 wk postoperatively (all P ≤ 0.018); there was no effect of delivery route (all P ≥ 0.632) or route × time interaction (all P ≥ 0.084). The glucose-dependent insulinotropic polypeptide (GIP) AUC was unchanged after RYGB (P = 0.819); however, GIP levels peaked earlier after RYGB with jejunal delivery. The ratio of insulin AUC to GLP-1 and GIP AUC decreased after surgery (P =.001 and 0.061, respectively) without an effect of delivery route over time (both P ≥ 0.646). Insulin sensitivity improved post-RYGB (P = 0.001) with no difference between the gastric and jejunal delivery of the mixed meal over time (P = 0.819). These data suggest that exclusion of nutrients from the foregut with RYGB does not improve glucose tolerance or insulin sensitivity. However, changes in the foregut response post-RYGB due to lack of nutrient exposure cannot be excluded. Our findings suggest that foregut bypass may alter the incretin response by enhanced nutrient delivery to the hindgut.
Pancreas transplantation with enteric drainage avoids the long-term urological complications of bladder drainage. Increasing use of this technique raises the possibility of complications from the enteric reconstruction. This report describes a patient five yr after left-sided pancreas transplant with Roux-en-Y enteric drainage, presenting with abdominal pain, leukocytosis and radiological evidence of bowel obstruction. Exploration revealed a volvulus of the Roux limb as it passed through the mesocolon, with necrosis of the allograft duodenum and marked congestion of the pancreas. This is the first report of pancreas graft loss due to this entity, which should be recognized as an unusual cause of abdominal pain after pancreas transplantation. Potential bowel complications related to the sigmoid mesentery in left-sided pancreas transplantation are additional reasons for right-sided placement of the pancreas allograft.
Hepaticojejunostomy is a standard biliary reconstruction method for infantile living donor liver transplantation (LDLT), but choledochocholedochostomy for infants is not generally accepted yet. Ten pediatric recipients weighing no more than 10 kg underwent duct-to-duct choledochocholedochostomy (DD) for biliary reconstruction for LDLT. Patients were followed up for a median period of 26.8 months (range: 4.0-79.0 months). The incidence of posttransplant biliary complications for DD was compared with that for Roux-en-Y hepaticojejunostomy (RY). No DD patients and 1 RY patient (5%) developed biliary leakage (P > 0.05), and biliary stricture occurred in 1 DD patient (10%) and none of the RY patients (P > 0.05); none of the DD patients and 5 RY patients (25%) suffered from uncomplicated cholangitis after LDLT (P > 0.05), and 1 DD patient (10%) and 2 RY patients (10%) died of causes unrelated to biliary complications. In conclusion, both hepaticojejunostomy and choledochocholedochostomy resulted in satisfactory outcome in terms of biliary complications, including leakage and stricture, for recipients weighing no more than 10 kg.
The purpose of this study is to describe the feasibility of using single-balloon enteroscopy (SBE) to perform endoscopic retrograde cholangiopancreatography (ERCP) in patients who had a prior Roux-en-Y (RY) anastomosis. This case series describes four patients, one with RY gastric bypass, two with RY due to bile duct injury, and one with RY after liver transplantation, who underwent ERCP with SBE. Cholangiography was successful in three of the four patients. In the procedure that was not successful, the enteroenterostomy site could not be located. The successful procedures ranged from 65-91 min in duration. Medication doses were higher than with typical ERCPs. No procedural complications occurred. SBE for ERCP is a feasible option for endoscopic access to the biliary tree in patients with prior RY anastomoses. Limitations of this technique include the time requirement, delay in identification of the enteroenterostomy site, potential learning curve, and immature technology lacking accessories.