TY - JOUR A1 - Reimer, Stanislaus A1 - Lock, Johan F. A1 - Flemming, Sven A1 - Weich, Alexander A1 - Widder, Anna A1 - Plaßmeier, Lars A1 - Döring, Anna A1 - Hering, Ilona A1 - Hankir, Mohammed K. A1 - Meining, Alexander A1 - Germer, Christoph-Thomas A1 - Groneberg, Kaja A1 - Seyfried, Florian T1 - Endoscopic management of large leakages after upper gastrointestinal surgery JF - Frontiers in Surgery N2 - Background Endoscopic vacuum therapy (EVT) is an evidence-based option to treat anastomotic leakages of the upper gastrointestinal (GI) tract, but the technical challenges and clinical outcomes of patients with large defects remain poorly described. Methods All patients with leakages of the upper GI tract that were treated with endoscopic negative pressure therapy at our institution from 2012–2021 were analyzed. Patients with large defects (>30 mm) as an indicator of complex treatment were compared to patients with smaller defects (control group). Results Ninety-two patients with postoperative anastomotic or staplerline leakages were identified, of whom 20 (21.7%) had large defects. Compared to the control group, these patients required prolonged therapy (42 vs. 14 days, p < 0.001) and hospital stay (63 vs. 26 days, p < 0.001) and developed significantly more septic complications (40 vs. 17.6%, p = 0.027.) which often necessitated additional endoscopic and/or surgical/interventional treatments (45 vs. 17.4%, p = 0.007.) Nevertheless, a resolution of leakages was achieved in 80% of patients with large defects, which was similar compared to the control group (p = 0.42). Multiple leakages, especially on the opposite side, along with other local unfavorable conditions, such as foreign material mass, limited access to the defect or extensive necrosis occurred significantly more often in cases with large defects (p < 0.001). Conclusions Overall, our study confirms that EVT for leakages even from large defects of the upper GI tract is feasible in most cases but comes with significant technical challenges. KW - anastomotic leakage KW - endoluminal KW - vacuum-assisted closure KW - negative pressure KW - endoscopic Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-274044 SN - 2296-875X VL - 9 ER - TY - JOUR A1 - Hankir, Mohammed K. A1 - Seyfried, Florian A1 - Schellinger, Isabel N. A1 - Schlegel, Nicolas A1 - Arora, Tulika T1 - Leaky gut as a potential culprit for the paradoxical dysglycemic response to gastric bypass-associated ileal microbiota JF - Metabolites N2 - Altered host-intestinal microbiota interactions are increasingly implicated in the metabolic benefits of Roux-en-Y gastric bypass (RYGB) surgery. We previously found, however, that RYGB-associated ileal microbiota can paradoxically impair host glycemic control when transferred to germ-free mice. Here we present complementary evidence suggesting that this could be due to the heightened development of systemic endotoxemia. Consistently, application of ileal content from RYGB-treated compared with sham-operated rats onto Caco-2 cell monolayers compromised barrier function and decreased expression of the barrier-stabilizing proteins claudin-4 and desmoglein-2. Our findings raise the possibility that RYGB-associated ileal microbiota produce and release soluble metabolites which locally increase intestinal permeability to promote systemic endotoxemia-induced insulin resistance, with potential implications for the treatment of RYGB patients who eventually relapse onto type 2 diabetes. KW - Roux-en-Y gastric bypass surgery KW - intestinal microbiota KW - intestinal epithelial barrier KW - systemic endotoxemia KW - type 2 diabetes Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234085 SN - 2218-1989 VL - 11 IS - 3 ER - TY - JOUR A1 - Rullmann, Michael A1 - Preusser, Sven A1 - Poppitz, Sindy A1 - Heba, Stefanie A1 - Gousias, Konstantinos A1 - Hoyer, Jana A1 - Schütz, Tatjana A1 - Dietrich, Arne A1 - Müller, Karsten A1 - Hankir, Mohammed K. A1 - Pleger, Burkhard T1 - Adiposity Related Brain Plasticity Induced by Bariatric Surgery JF - Froniers in Human Neuroscience N2 - Previous magnetic resonance imaging (MRI) studies revealed structural-functional brain reorganization 12 months after gastric-bypass surgery, encompassing cortical and subcortical regions of all brain lobes as well as the cerebellum. Changes in the mean of cluster-wise gray/white matter density (GMD/WMD) were correlated with the individual loss of body mass index (BMI), rendering the BMI a potential marker of widespread surgery-induced brain plasticity. Here, we investigated voxel-by-voxel associations between surgery-induced changes in adiposity, metabolism and inflammation and markers of functional and structural neural plasticity. We re-visited the data of patients who underwent functional and structural MRI, 6 months (n = 27) and 12 months after surgery (n = 22), and computed voxel-wise regression analyses. Only the surgery-induced weight loss was significantly associated with brain plasticity, and this only for GMD changes. After 6 months, weight loss overlapped with altered GMD in the hypothalamus, the brain's homeostatic control site, the lateral orbitofrontal cortex, assumed to host reward and gustatory processes, as well as abdominal representations in somatosensory cortex. After 12 months, weight loss scaled with GMD changes in right cerebellar lobule VII, involved in language-related/cognitive processes, and, by trend, with the striatum, assumed to underpin (food) reward. These findings suggest time-dependent and weight-loss related gray matter plasticity in brain regions involved in the control of eating, sensory processing and cognitive functioning. KW - adiposity KW - magnetic resonance imaging KW - brain plasticity KW - bariatric surgery KW - gastric-bypass surgery Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227168 VL - 13 ER - TY - JOUR A1 - Chen, Jeremy Tsung-Chieh A1 - Schmidt, Lea A1 - Schürger, Christina A1 - Hankir, Mohammed K. A1 - Krug, Susanne M. A1 - Rittner, Heike L. T1 - Netrin-1 as a multitarget barrier stabilizer in the peripheral nerve after injury JF - International Journal of Molecular Sciences N2 - The blood–nerve barrier and myelin barrier normally shield peripheral nerves from potentially harmful insults. They are broken down during nerve injury, which contributes to neuronal damage. Netrin-1 is a neuronal guidance protein with various established functions in the peripheral and central nervous systems; however, its role in regulating barrier integrity and pain processing after nerve injury is poorly understood. Here, we show that chronic constriction injury (CCI) in Wistar rats reduced netrin-1 protein and the netrin-1 receptor neogenin-1 (Neo1) in the sciatic nerve. Replacement of netrin-1 via systemic or local administration of the recombinant protein rescued injury-induced nociceptive hypersensitivity. This was prevented by siRNA-mediated knockdown of Neo1 in the sciatic nerve. Mechanistically, netrin-1 restored endothelial and myelin, but not perineural, barrier function as measured by fluorescent dye or fibrinogen penetration. Netrin-1 also reversed the decline in the tight junction proteins claudin-5 and claudin-19 in the sciatic nerve caused by CCI. Our findings emphasize the role of the endothelial and myelin barriers in pain processing after nerve damage and reveal that exogenous netrin-1 restores their function to mitigate CCI-induced hypersensitivity via Neo1. The netrin-1-neogenin-1 signaling pathway may thus represent a multi-target barrier protector for the treatment of neuropathic pain. KW - neuropathic pain KW - netrin-1 KW - blood-nerve barrier KW - tight junction proteins Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-261695 SN - 1422-0067 VL - 22 IS - 18 ER - TY - JOUR A1 - Flemming, Sven A1 - Hankir, Mohammed K. A1 - Kusan, Simon A1 - Krone, Manuel A1 - Anger, Friedrich A1 - Germer, Christoph-Thomas A1 - Wiegering, Armin T1 - Safety of elective abdominal and vascular surgery during the COVID-19 pandemic: a retrospective single-center study JF - European Journal of Medical Research N2 - Background Patients with coronavirus disease 2019 (COVID-19) who undergo surgery have impaired postoperative outcomes and increased mortality. Consequently, elective and semi-urgent operations on the increasing number of patients severely affected by COVID-19 have been indefinitely postponed.in many countries with unclear implications on disease progression and overall survival. The purpose of this study was to evaluate whether the establishment of a standardized screening program for acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is sufficient to ensure high-quality medical and surgical treatment of COVID-19 and non-COVID-19 patients while minimizing in-hospital SARS-CoV-2 transmission. Methods The screening program comprised polymerase chain reaction (PCR) testing of nasopharyngeal swabs and a standardized questionnaire about potential symptoms for SARS-CoV-2 infection. All elective and emergency patients admitted to the surgical department of a tertiary-care hospital center in Lower Franconia, Germany, between March and May 2020 were included and their characteristics were recorded. Results Out of the study population (n = 657), 509 patients (77.5%) had at least one risk factor for a potentially severe course of COVID-19 and 164 patients (25%) were active smokers. The average 7-day incidence in Lower Franconia was 24.0/100,000 during the observation period. Preoperative PCR testing revealed four asymptomatic positive patients out of the 657 tested patients. No postoperative SARS-CoV-2 infection or transmission could be detected. Conclusion The implementation of a standardized preoperative screening program to both COVID-19 and non-COVID-19 patients can ensure high-quality surgical care while minimizing infection risk for healthcare workers and potential in-hospital transmission. KW - SARS-CoV-2 KW - COVID-19 KW - elective surgery KW - screening KW - PCR Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-264975 VL - 26 ER - TY - JOUR A1 - Hoffmann, Annett A1 - Ebert, Thomas A1 - Hankir, Mohammed K. A1 - Flehmig, Gesine A1 - Klöting, Nora A1 - Jessnitzer, Beate A1 - Lössner, Ulrike A1 - Stumvoll, Michael A1 - Blüher, Matthias A1 - Fasshauer, Mathias A1 - Tönjes, Anke A1 - Miehle, Konstanze A1 - Kralisch, Susan T1 - Leptin improves parameters of brown adipose tissue thermogenesis in lipodystrophic mice JF - Nutrients N2 - Lipodystrophy syndromes (LD) are a heterogeneous group of very rare congenital or acquired disorders characterized by a generalized or partial lack of adipose tissue. They are strongly associated with severe metabolic dysfunction due to ectopic fat accumulation in the liver and other organs and the dysregulation of several key adipokines, including leptin. Treatment with leptin or its analogues is therefore sufficient to reverse some of the metabolic symptoms of LD in patients and in mouse models through distinct mechanisms. Brown adipose tissue (BAT) thermogenesis has emerged as an important regulator of systemic metabolism in rodents and in humans, but it is poorly understood how leptin impacts BAT in LD. Here, we show in transgenic C57Bl/6 mice overexpressing sterol regulatory element-binding protein 1c in adipose tissue (Tg (aP2-nSREBP1c)), an established model of congenital LD, that daily subcutaneous administration of 3 mg/kg leptin for 6 to 8 weeks increases body temperature without affecting food intake or body weight. This is associated with increased protein expression of the thermogenic molecule uncoupling protein 1 (UCP1) and the sympathetic nerve marker tyrosine hydroxylase (TH) in BAT. These findings suggest that leptin treatment in LD stimulates BAT thermogenesis through sympathetic nerves, which might contribute to some of its metabolic benefits by providing a healthy reservoir for excess circulating nutrients. KW - lipodystrophy KW - leptin KW - brown adipose tissue KW - thermogenesis KW - uncoupling protein 1 KW - sympathetic nervous system Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-242787 SN - 2072-6643 VL - 13 IS - 8 ER - TY - JOUR A1 - Hankir, Mohammed K. A1 - Rotzinger, Laura A1 - Nordbeck, Arno A1 - Corteville, Caroline A1 - Dischinger, Ulrich A1 - Knop, Juna-Lisa A1 - Hoffmann, Annett A1 - Otto, Christoph A1 - Seyfried, Florian T1 - Leptin receptors are not required for Roux-en-Y gastric bypass surgery to normalize energy and glucose homeostasis in rats JF - Nutrients N2 - Sensitization to the adipokine leptin is a promising therapeutic strategy against obesity and its comorbidities and has been proposed to contribute to the lasting metabolic benefits of Roux-en-Y gastric bypass (RYGB) surgery. We formally tested this idea using Zucker fatty fa/fa rats as an established genetic model of obesity, glucose intolerance, and fatty liver due to leptin receptor deficiency. We show that the changes in body weight in these rats following RYGB largely overlaps with that of diet-induced obese Wistar rats with intact leptin receptors. Further, food intake and oral glucose tolerance were normalized in RYGB-treated Zucker fatty fa/fa rats to the levels of lean Zucker fatty fa/+ controls, in association with increased glucagon-like peptide 1 (GLP-1) and insulin release. In contrast, while fatty liver was also normalized in RYGB-treated Zucker fatty fa/fa rats, their circulating levels of the liver enzyme alanine aminotransferase (ALT) remained elevated at the level of obese Zucker fatty fa/fa controls. These findings suggest that the leptin system is not required for the normalization of energy and glucose homeostasis associated with RYGB, but that its potential contribution to the improvements in liver health postoperatively merits further investigation. KW - Roux-en-Y gastric bypass surgery KW - energy homeostasis KW - glucose homeostasis KW - fatty liver KW - leptin system KW - Zucker fatty fa/fa rats Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239550 SN - 2072-6643 VL - 13 IS - 5 ER - TY - JOUR A1 - Plassmeier, Lars A1 - Hankir, Mohammed K. A1 - Seyfried, Florian T1 - Impact of Excess Body Weight on Postsurgical Complications JF - Visceral Medicine N2 - Background: Obesity is considered a risk factor for postoperative complications as it can limit exposure to the operation field, thereby significantly prolonging surgery time. Obesity-associated comorbidities, such as low-grade systemic inflammation, impaired functional status, and type 2 diabetes, are independent risk factors for impaired anastomotic wound healing and nonsurgical site infections. If obesity itself is an independent risk factor for surgical complications remains controversial, but the reason for this is largely unexplored. Summary: A MEDLINE literature search was performed using the terms: “obesity,” “excess body weight,” and “surgical complications.” Out of 65,493 articles 432 meta-analyses were screened, of which 25 meta-analyses were on the subject. The vast majority of complex oncologic procedures in the field of visceral surgery have shown higher complication rates in obese patients. Meta-analyses from the last 10 to 15 years with high numbers of patients enrolled consistently have shown longer operation times, higher blood loss, longer hospital stay for colorectal procedures, oncologic upper gastrointestinal (GI) procedures, and pancreatic surgery. Interestingly, these negative effects seem not to affect the overall survival in oncologic patients, especially in esophageal resections. A selection bias in oncologic upper GI patients may have influenced the results with higher BMI in upper GI cancer to be a predictor for better nutritional and performance status. Key Messages: Contrary to bariatric surgery, only limited evidence indicated that site and type of surgery, the approach to the abdominal cavity (laparoscopic vs. open), institutional factors, and the type of perioperative care such as ERAS protocols may play a role in determining postsurgical complications in obese patients. The initial question remains therefore partially unanswered. Large nationwide register-based studies are necessary to better understand which aspects of obesity and its related comorbidities define it as a risk factor for surgical complications. KW - obesity KW - surgical complications KW - laparoscopy Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244890 SN - 2297-4725 SN - 2297-475X VL - 37 IS - 4 ER - TY - JOUR A1 - Griebsch, Nora-Isabell A1 - Kern, Johanna A1 - Hansen, Jonas A1 - Rullmann, Michael A1 - Luthardt, Julia A1 - Helfmeyer, Stephanie A1 - Dekorsy, Franziska J. A1 - Soeder, Marvin A1 - Hankir, Mohammed K. A1 - Zientek, Franziska A1 - Becker, Georg-Alexander A1 - Patt, Marianne A1 - Meyer, Philipp M. A1 - Dietrich, Arne A1 - Blüher, Matthias A1 - Ding, Yu-Shin A1 - Hilbert, Anja A1 - Sabri, Osama A1 - Hesse, Swen T1 - Central serotonin/noradrenaline transporter availability and treatment success in patients with obesity JF - Brain Sciences N2 - Serotonin (5-hydroxytryptamine, 5-HT) as well as noradrenaline (NA) are key modulators of various fundamental brain functions including the control of appetite. While manipulations that alter brain serotoninergic signaling clearly affect body weight, studies implicating 5-HT transporters and NA transporters (5-HTT and NAT, respectively) as a main drug treatment target for human obesity have not been conclusive. The aim of this positron emission tomography (PET) study was to investigate how these central transporters are associated with changes of body weight after 6 months of dietary intervention or Roux-en-Y gastric bypass (RYGB) surgery in order to assess whether 5-HTT as well as NAT availability can predict weight loss and consequently treatment success. The study population consisted of two study cohorts using either the 5-HTT-selective radiotracer [\(^{11}\)C]DASB to measure 5-HTT availability or the NAT-selective radiotracer [\(^{11}\)C]MRB to assess NAT availability. Each group included non-obesity healthy participants, patients with severe obesity (body mass index, BMI, >35 kg/m\(^2\)) following a conservative dietary program (diet) and patients undergoing RYGB surgery within a 6-month follow-up. Overall, changes in BMI were not associated with changes of both 5-HTT and NAT availability, while 5-HTT availability in the dorsal raphe nucleus (DRN) prior to intervention was associated with substantial BMI reduction after RYGB surgery and inversely related with modest BMI reduction after diet. Taken together, the data of our study indicate that 5-HTT and NAT are involved in the pathomechanism of obesity and have the potential to serve as predictors of treatment outcomes. KW - obesity KW - serotonin KW - noradrenaline KW - serotonin transporter KW - noradrenaline transporter KW - Roux-en-Y gastric bypass surgery KW - body mass index (BMI; kg/m\(^2\)) KW - radiotracer KW - PET KW - PET imaging Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-290294 SN - 2076-3425 VL - 12 IS - 11 ER - TY - JOUR A1 - Hering, Ilona A1 - Dörries, Luise A1 - Flemming, Sven A1 - Krietenstein, Laura A1 - Koschker, Ann-Kathrin A1 - Fassnacht, Martin A1 - Germer, Christoph-Thomas A1 - Hankir, Mohammed K. A1 - Seyfried, Florian T1 - Impact of preoperative weight loss achieved by gastric balloon on peri- and postoperative outcomes of bariatric surgery in super-obese patients: a retrospective matched-pair analysis JF - Langenbeck’s Archives of Surgery N2 - Background An intragastric balloon is used to cause weight loss in super-obese patients (BMI > 60 kg/m\(^2\)) prior to bariatric surgery. Whether weight loss from intragastric balloon influences that from bariatric surgery is poorly studied. Methods In this retrospective, single-center study, the effects of intragastric balloon in 26 patients (BMI 69.26 ± 6.81) on weight loss after bariatric surgery (primary endpoint), postoperative complications within 30 days, hospital readmission, operation time, and MTL30 (secondary endpoints) were evaluated. Fifty-two matched-pair patients without intragastric balloon prior to bariatric surgery were used as controls. Results Intragastric balloon resulted in a weight loss of 17.3 ± 14.1 kg (BMI 5.75 ± 4.66 kg/m\(^2\)) with a nadir after 5 months. Surgical and postoperative outcomes including complications were comparable between both groups. Total weight loss was similar in both groups (29.0% vs. 32.2%, p = 0.362). Direct postoperative weight loss was more pronounced in the control group compared to the gastric balloon group (29.16 ± 7.53% vs 23.78 ± 9.89% after 1 year, p < 0.05 and 32.13 ± 10.5% vs 22.21 ± 10.9% after 2 years, p < 0.05), who experienced an earlier nadir and started to regain weight during the follow-up. Conclusion A multi-stage therapeutic approach with gastric balloon prior to bariatric surgery in super-obese patients may be effective to facilitate safe surgery. However, with the gastric balloon, pre-treated patients experienced an attenuated postoperative weight loss with an earlier nadir and earlier body weight regain. This should be considered when choosing the appropriate therapeutic regime and managing patients’ expectations. KW - obesity KW - super-obesity KW - intragastric balloon KW - sleeve gastrectomy KW - Roux-en-Y gastric bypass Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-323909 VL - 407 IS - 5 ER -