Single-nucleus transcriptomics identifies separate classes of UCP1 and futile cycle adipocytes.

Adipose tissue can recruit catabolic adipocytes that utilize chemical energy to dissipate heat. This process occurs either by uncoupled respiration through uncoupling protein 1 (UCP1) or by utilizing ATP-dependent futile cycles (FCs). However, it remains unclear how these pathways coexist since both processes rely on the mitochondrial membrane potential. Utilizing single-nucleus RNA sequencing to deconvolute the heterogeneity of subcutaneous adipose tissue in mice and humans, we identify at least 2 distinct subpopulations of beige adipocytes: FC-adipocytes and UCP1-beige adipocytes. Importantly, we demonstrate that the FC-adipocyte subpopulation is highly metabolically active and utilizes FCs to dissipate energy, thus contributing to thermogenesis independent of Ucp1. Furthermore, FC-adipocytes are important drivers of systemic energy homeostasis and linked to glucose metabolism and obesity resistance in humans. Taken together, our findings identify a noncanonical thermogenic adipocyte subpopulation, which could be an important regulator of energy homeostasis in mammals.

The difficult hepaticojejunostomy after pancreatic head resection: reconstruction with a T tube.

BACKGROUND: After pancreatic head resection, bile leaks from a difficult hepaticojejunostomy secondary to a small or fragile common hepatic duct may be reduced by a T tube at the side of the anastomosis. METHODS: A retrospective analysis of patients who underwent a difficult hepaticojejunostomy without or with a T tube was performed. RESULTS: In 48% (55/114) of patients, a T tube was placed at the side of the hepaticojejunostomy; 52% (59/114) did not have a T tube. Bile leaks occurred in 12% (14/114) (9% [5/55] in patients with a T tube vs 15% [9/59] without a T tube, P = .316). Bile leaks were associated with mortality, abscess formation, hemorrhage, and sepsis. Seven percent (8/114) of patients required revisional laparotomy (2% [1/55] with a T tube vs 12% [7/59] without a T tube, P = .036). Mortality was not different between the groups. Minor T-tube-associated complications occurred in 15% (8/55) without major complications. CONCLUSIONS: Augmentation of anastomosis with a T tube cannot prevent biliary leakage but does reduce the severity of bile leaks, resulting in less reoperations.

Rare solid tumors of the pancreas as differential diagnosis of pancreatic adenocarcinoma.

CONTEXT: Rare solid tumors of the pancreas can be misinterpreted as primary pancreatic cancer. OBJECTIVE: The aim of this study was to report our experience in the treatment of patients with rare tumor lesions of the pancreas and to discuss clinical and pathological characteristics in the context of the role of surgery. DESIGN: Data from patients of our prospective data-base with rare benign and malignant tumors of the pancreas, treated in our division from January 2004 to August 2010, were analyzed retrospectively. RESULTS: One-thousand and ninety-eight patients with solid tumors of the pancreas underwent pancreatic surgery. In 19 patients (10 women, 9 men) with a mean age of 57 years (range: 20-74 years) rare pancreatic tumors (metastasis, solid pseudopapillary tumor, teratoma, hemangioma, accessory spleen, lymphoepithelial cyst, hamartoma, sarcoidosis, yolk sac tumor) were the reason for surgical intervention. CONCLUSION: If rare benign and malignant pancreatic tumors, intrapancreatic metastasis, as well as pancreatic malformations or other abnormalities, present themselves as solid masses of the pancreas, they constitute an important differential diagnosis to primary pancreatic neoplasia, e.g. pancreatic ductal adenocarcinoma. Clinical imaging techniques cannot always rule out malignancy, thus operative exploration often remains the treatment of choice to provide the correct diagnosis and initiate adequate surgical therapy.

Bacteribilia with resistant microorganisms after preoperative biliary drainage--the influence of bacteria on postoperative outcome.

BACKGROUND: In pancreatic surgery, preoperative biliary drainage (PBD) leads to bacteribilia. Whether positive bile duct cultures are associated with a higher postoperative morbidity might be related to the resistance of the species isolated from bile. STUDY: Intraoperative bile duct cultures were collected from all patients who underwent pancreatic surgery. Postoperative morbidity was analyzed according to the species and the resistance found on bile duct cultures. RESULTS: Fifty-five percent (166/301) of patients had PBD, while 45% (135/301) underwent primary operation. PBD was associated with a positive bile duct culture in 87% (144/166) versus 21% (28/135) in patients without PBD (p = 0.001) and polymicrobial infections in 53% (88/166) versus 6% (8/135) (p = 0.001). Postoperative morbidity was 40% (121/301); mortality was 3% (9/301). PBD was not associated with morbidity and mortality, but resistant species on bile duct cultures lead to significantly more postoperative complications, 54% (25/46) versus 38% (96/255) (p = 0.033), with significantly more antibiotic therapies. CONCLUSION: PBD is associated with polymicrobial infections with resistant microorganisms, resulting in more postoperative complications. Since PBD cannot always be avoided, surgeons and gastroenterologists must be aware of their institutional surveillance data to identify patients at risk for postoperative complications.

Histomorphological features of the pancreatic remnant as independent risk factors for postoperative pancreatic fistula: a matched-pairs analysis.

BACKGROUND/AIMS: Postoperative pancreatic fistula (POPF) is a major complication after resective pancreatic surgery. This study aimed to identify histomorphological features of the pancreatic remnant as independent determinants for the development of POPF. METHODS: Twenty-five patients, 3.6% of 696 resections over a period of 5 years, who developed POPF were matched for age, gender, diagnosis, comorbidities, surgeon and procedure with 25 controls without POPF. Pancreatic duct size and index, fibrosis grade, fat content, edema, and signs of chronic and acute inflammation were measured in frozen sections of the resection margin and were then compared. RESULTS: The POPF rate was 12.2 and 2.6% after distal pancreatectomy and pancreatoduodenectomy, respectively. The POPF group was characterized by a longer ICU and total postoperative stay, higher rate of reoperations and complications. Their pancreata were softer at palpation (88 vs. 56%). Their pancreatic duct was smaller (2.5 vs. 3.2 mm) and their pancreatic fat content higher (16 vs. 8%). High inter- and intralobular fat content, small duct size, low interlobular fibrosis grade and lack of signs of chronic pancreatitis were predictors of POPF development. A score including these parameters identified high-risk patients with a sensitivity of 92% and a specificity of 84%. CONCLUSION: Histomorphological features of the pancreatic remnant play an independent role as risk factors for the development of POPF. A simple histological score based on the frozen sections may already intraoperatively predict the risk of POPF development.

Treatment of acute delayed visceral hemorrhage after pancreatic surgery from hepatic arteries with covered stents.

BACKGROUND: Delayed visceral hemorrhage following pancreatic surgery is a rare but life-threatening complication. Usually hemorrhage originates from pseudoaneurysms secondary to pancreatic or biliary fistula. Re-laparotomy is often associated with high morbidity and mortality. Endovascular occlusion with metallic coils can stop pseudoaneurysmatic bleeding, but hepatic artery occlusion can result in severe organ damage. Interventional treatment with covered stents is an alternative providing persistent organ perfusion. RESULTS: In our department endovascular stenting for visceral hemorrhage was introduced in November 2008. From November 2008 until October 2009, 303 patients underwent pancreatic surgery at our institution. Among those, four patients were successfully treated with covered stents for delayed visceral hemorrhage. In all four patients bleeding originated from hepatic arteries. Mean onset of hemorrhage was 24 days after surgery. Endovascular stenting was successful in all four patients. None of these patients required re-operation or died during the study. CONCLUSION: Treatment of delayed visceral hemorrhage from hepatic arteries after pancreatic surgery with covered stents is safe and effective. Endovascular stenting is associated with a lower morbidity than re-laparotomy or coil embolisation. Emergency angiography with endovascular stenting should be considered for all patients with delayed hemorrhage from hepatic arteries after pancreatic surgery.

Contemporary single-center surgical experiences in redo procedures of the pancreas: improved outcome and reduction of operative risk.

INTRODUCTION: Redo procedures of the pancreas are complex operations associated with significant morbidity and mortality rates. The operative risk may be minimised when indications for redo procedure are well reflected and operation is performed by an experienced surgeon. The aim of this study was to confirm this hypothesis evaluating our experiences with redo procedures. METHODS: We reviewed 28 patients (mean age of 54 years; range 11-75 years) undergoing a redo procedure of the pancreas from January 2004 to June 2008 at our hospital. The term redo procedure was defined as a pancreatic reoperation that was carried out after preceding pancreatic surgery. Relaparotomies following acute complications after pancreatic surgery were not taken into consideration. RESULTS: The following parameters were evaluated: median operative time 332 min (range 160-730 min), median intraoperative blood loss 625 ml (range 300-2,800 ml), median postoperative stay on Intensive Care Unit 20 h (range 0-112 h), median postoperative hospital stay 15 days (range 7-98), morbidity (14%), and mortality (3.6%). CONCLUSIONS: Redo procedures of the pancreas can be performed with low complication rates. In order to achieve a satisfactory outcome, the indication of redo procedures has to be well reflected, and operation may be performed by specialised and experienced surgeons.