@article{SeyfriedvonRahdenMirasetal.2015,
  author    = {Seyfried, Florian and von Rahden, Burkhard H. and Miras, Alexander D. and Gasser, Martin and Maeder, Uwe and Kunzmann, Volker and Germer, Christoph-Thomas and Pelz, J{\"o}rg O. W. and Kerscher, Alexander G.},
  title     = {Incidence, time course and independent risk factors for metachronous peritoneal carcinomatosis of gastric origin - a longitudinal experience from a prospectively collected database of 1108 patients},
  series = {BMC Cancer},
  volume    = {15},
  journal   = {BMC Cancer},
  number    = {73},
  doi       = {10.1186/s12885-015-1081-8},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125014},
  year      = {2015},
  abstract  = {Background Comprehensive evidence on the incidence, time course and independent risk factors of metachronous peritoneal carcinomatosis (metaPC) in gastric cancer patients treated with curative intent in the context of available systemic combination chemotherapies is lacking. Methods Data from a prospectively collected single-institutional Center Cancer Registry with 1108 consecutive patients with gastric adenocarcinoma (GC), clinical, histological and survival data were analyzed for independent risk factors and prognosis with focus on the development of metaPC. Findings were then stratified to the time periods of treatment with surgery alone, 5-Fluorouracil-only and contemporary combined systemic perioperative chemotherapy strategies, respectively. Results Despite R0 D2 gastrectomy (n = 560), 49.6\% (±5.4\%) of the patients were diagnosed with tumour recurrence and 15.5\% (±1.8\%) developed metaPC after a median time of 17.7 (15.1-20.3) months after surgery resulting in a tumour related mortality of 100\% with a median survival of 3.0 months (2.1 - 4.0). Independent risk factors for the development of metaPC were serosa positive T-category, nodal positive-status, signet cell and undifferentiated gradings (G3/G4). Contemporary systemic combination chemotherapy did not improve the incidence and prognosis of metaPC (p = 0.54). Conclusions Despite significant improvements in the overall survival for the complete cohort with gastric cancer over time, those patients with metaPC did not experience the same benefits. The lack of change in the incidence, and persistent poor prognosis of metaPC after curative surgery expose the need for further prevention and/or improved treatment options for this devastating condition.},
  language  = {en}
}
@article{MirasSeyfriedPhinikaridouetal.2014,
  author    = {Miras, Alexander D. and Seyfried, Florian and Phinikaridou, Alkystis and Andia, Marcelo E. and Christakis, Ioannis and Spector, Alan C. and Botnar, Rene M. and le Roux, Carel W.},
  title     = {Rats Fed Diets with Different Energy Contribution from Fat Do Not Differ in Adiposity},
  series = {OBESITY FACTS},
  volume    = {7},
  journal   = {OBESITY FACTS},
  number    = {5},
  doi       = {10.1159/000368622},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-115249},
  pages     = {302-310},
  year      = {2014},
  abstract  = {Objective: To determine whether rats reaching the same body mass, having been fed either a low-fat (LFD) or a high-fat diet (HFD), differ in white adipose tissue (WAT) deposition. Methods: In experiment 1, 22 Sprague-Dawley rats of the same age were divided into 11 rats with body mass below the batch median and fed a HFD, and 11 above the median and fed a LFD. In experiment 2, 20 Sprague-Dawley rats of the same age and starting body mass were randomised to either a HFD or LFD. When all groups reached similar final body mass, WAT was quantified using magnetic resonance imaging (MRI), dissection, and plasma leptin. Results: In experiment 1, both groups reached similar final body mass at the same age; in experiment 2 the HFD group reached similar final body mass earlier than the LFD group. There were no significant differences in WAT as assessed by MRI or leptin between the HFD and LFD groups in both experiments. Dissection revealed a trend for higher retroperitoneal and epididymal adiposity in the HFD groups in both experiments. Conclusions: We conclude that at similar body mass, adiposity is independent of the macronutrient composition of the feeding regimen used to achieve it. (C) 2014 S Karger GmbH, Freiburg},
  language  = {en}
}
@article{ReimerLockFlemmingetal.2022,
  author    = {Reimer, Stanislaus and Lock, Johan F. and Flemming, Sven and Weich, Alexander and Widder, Anna and Plaßmeier, Lars and D{\"o}ring, Anna and Hering, Ilona and Hankir, Mohammed K. and Meining, Alexander and Germer, Christoph-Thomas and Groneberg, Kaja and Seyfried, Florian},
  title     = {Endoscopic management of large leakages after upper gastrointestinal surgery},
  series = {Frontiers in Surgery},
  volume    = {9},
  journal   = {Frontiers in Surgery},
  issn      = {2296-875X},
  doi       = {10.3389/fsurg.2022.885244},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-274044},
  year      = {2022},
  abstract  = {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.},
  language  = {en}
}
@article{WidderKelmReibetanzetal.2022,
  author    = {Widder, Anna and Kelm, Matthias and Reibetanz, Joachim and Wiegering, Armin and Matthes, Niels and Germer, Christoph-Thomas and Seyfried, Florian and Flemming, Sven},
  title     = {Robotic-assisted versus laparoscopic left hemicolectomy — postoperative inflammation status, short-term outcome and cost effectiveness},
  series = {International Journal of Environmental Research and Public Health},
  volume    = {19},
  journal   = {International Journal of Environmental Research and Public Health},
  number    = {17},
  issn      = {1660-4601},
  doi       = {10.3390/ijerph191710606},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-286203},
  year      = {2022},
  abstract  = {Robotic-assisted colon surgery may contain advantages over the laparoscopic approach, but clear evidence is sparse. This study aimed to analyze postoperative inflammation status, short-term outcome and cost-effectiveness of robotic-assisted versus laparoscopic left hemicolectomy. All consecutive patients who received minimal-invasive left hemicolectomy at the Department of Surgery I at the University Hospital of Wuerzburg in 2021 were prospectively included. Importantly, no patient selection for either procedure was carried out. The robotic-assisted versus laparoscopic approaches were compared head to head for postoperative short-term outcomes as well as cost-effectiveness. A total of 61 patients were included, with 26 patients having received a robotic-assisted approach. Baseline characteristics did not differ among the groups. Patients receiving a robotic-assisted approach had a significantly decreased length of hospital stay as well as lower rates of complications in comparison to patients who received laparoscopic surgery (n = 35). In addition, C-reactive protein as a marker of systemic stress response was significantly reduced postoperatively in patients who were operated on in a robotic-assisted manner. Consequently, robotic-assisted surgery could be performed in a cost-effective manner. Thus, robotic-assisted left hemicolectomy represents a safe and cost-effective procedure and might improve patient outcomes in comparison to laparoscopic surgery.},
  language  = {en}
}
@article{HeringDoerriesFlemmingetal.2022,
  author    = {Hering, Ilona and D{\"o}rries, Luise and Flemming, Sven and Krietenstein, Laura and Koschker, Ann-Kathrin and Fassnacht, Martin and Germer, Christoph-Thomas and Hankir, Mohammed K. and Seyfried, Florian},
  title     = {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},
  series = {Langenbeck's Archives of Surgery},
  volume    = {407},
  journal   = {Langenbeck's Archives of Surgery},
  number    = {5},
  doi       = {10.1007/s00423-022-02472-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-323909},
  pages     = {1873-1879},
  year      = {2022},
  abstract  = {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.},
  language  = {en}
}
@article{ReimerSeyfriedFlemmingetal.2022,
  author    = {Reimer, Stanislaus and Seyfried, Florian and Flemming, Sven and Brand, Markus and Weich, Alexander and Widder, Anna and Plaßmeier, Lars and Kraus, Peter and D{\"o}ring, Anna and Hering, Ilona and Hankir, Mohammed K. and Meining, Alexander and Germer, Christoph-Thomas and Lock, Johan F. and Groneberg, Kaja},
  title     = {Evolution of endoscopic vacuum therapy for upper gastrointestinal leakage over a 10-year period: a quality improvement study},
  series = {Surgical Endoscopy},
  volume    = {36},
  journal   = {Surgical Endoscopy},
  number    = {12},
  doi       = {10.1007/s00464-022-09400-w},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-323953},
  pages     = {9169-9178},
  year      = {2022},
  abstract  = {Background Endoscopic vacuum therapy (EVT) is an effective treatment option for leakage of the upper gastrointestinal (UGI) tract. The aim of this study was to evaluate the clinical impact of quality improvements in EVT management on patients' outcome. Methods All patients treated by EVT at our center during 2012-2021 were divided into two consecutive and equal-sized cohorts (period 1 vs. period 2). Over time several quality improvement strategies were implemented including the earlier diagnosis and EVT treatment and technical optimization of endoscopy. The primary endpoint was defined as the composite score MTL30 (mortality, transfer, length-of-stay > 30 days). Secondary endpoints included EVT efficacy, complications, in-hospital mortality, length-of-stay (LOS) and nutrition status at discharge. Results A total of 156 patients were analyzed. During the latter period the primary endpoint MTL30 decreased from 60.8 to 39.0\% (P = .006). EVT efficacy increased from 80 to 91\% (P = .049). Further, the need for additional procedures for leakage management decreased from 49.9 to 29.9\% (P = .013) and reoperations became less frequent (38.0\% vs.15.6\%; P = .001). The duration of leakage therapy and LOS were shortened from 25 to 14 days (P = .003) and 38 days to 25 days (P = .006), respectively. Morbidity (as determined by the comprehensive complication index) decreased from 54.6 to 46.5 (P = .034). More patients could be discharged on oral nutrition (70.9\% vs. 84.4\%, P = .043). Conclusions Our experience confirms the efficacy of EVT for the successful management of UGI leakage. Our quality improvement analysis demonstrates significant changes in EVT management resulting in accelerated recovery, fewer complications and improved functional outcome.},
  language  = {en}
}
@article{HankirPattPattetal.2017,
  author    = {Hankir, Mohammed K. and Patt, Marianne and Patt, J{\"o}rg T. W. and Becker, Georg A. and Rullmann, Michael and Kranz, Mathias and Deuther-Conrad, Winnie and Schischke, Kristin and Seyfried, Florian and Brust, Peter and Hesse, Swen and Sabri, Osama and Kr{\"u}gel, Ute and Fenske, Wiebke},
  title     = {Suppressed fat appetite after Roux-en-Y gastric bypass surgery associates with reduced brain mu-opioid receptor availability in diet-induced obese male rats},
  series = {Frontiers in Neuroscience},
  volume    = {10},
  journal   = {Frontiers in Neuroscience},
  doi       = {10.3389/fnins.2016.00620},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-181130},
  year      = {2017},
  abstract  = {Brain μ-opioid receptors (MORs) stimulate high-fat (HF) feeding and have been implicated in the distinct long term outcomes on body weight of bariatric surgery and dieting. Whether alterations in fat appetite specifically following these disparate weight loss interventions relate to changes in brain MOR signaling is unknown. To address this issue, diet-induced obese male rats underwent either Roux-en-Y gastric bypass (RYGB) or sham surgeries. Postoperatively, animals were placed on a two-choice diet consisting of low-fat (LF) and HF food and sham-operated rats were further split into ad libitum fed (Sham-LF/HF) and body weight-matched (Sham-BWM) to RYGB groups. An additional set of sham-operated rats always only on a LF diet (Sham-LF) served as lean controls, making four experimental groups in total. Corresponding to a stage of weight loss maintenance for RYGB rats, two-bottle fat preference tests in conjunction with small-animal positron emission tomography (PET) imaging studies with the selective MOR radioligand [\(^{11}\)C]carfentanil were performed. Brains were subsequently collected and MOR protein levels in the hypothalamus, striatum, prefrontal cortex and orbitofrontal cortex were analyzed by Western Blot. We found that only the RYGB group presented with intervention-specific changes: having markedly suppressed intake and preference for high concentration fat emulsions, a widespread reduction in [\(^{11}\)C]carfentanil binding potential (reflecting MOR availability) in various brain regions, and a downregulation of striatal and prefrontal MOR protein levels compared to the remaining groups. These findings suggest that the suppressed fat appetite caused by RYGB surgery is due to reduced brain MOR signaling, which may contribute to sustained weight loss unlike the case for dieting.},
  language  = {en}
}
@article{Trujillo‐VieraEl‐MerahbiSchmidtetal.2021,
  author    = {Trujillo-Viera, Jonathan and El-Merahbi, Rabih and Schmidt, Vanessa and Karwen, Till and Loza-Valdes, Angel and Strohmeyer, Akim and Reuter, Saskia and Noh, Minhee and Wit, Magdalena and Hawro, Izabela and Mocek, Sabine and Fey, Christina and Mayer, Alexander E. and L{\"o}ffler, Mona C. and Wilhelmi, Ilka and Metzger, Marco and Ishikawa, Eri and Yamasaki, Sho and Rau, Monika and Geier, Andreas and Hankir, Mohammed and Seyfried, Florian and Klingenspor, Martin and Sumara, Grzegorz},
  title     = {Protein Kinase D2 drives chylomicron-mediated lipid transport in the intestine and promotes obesity},
  series = {EMBO Molecular Medicine},
  volume    = {13},
  journal   = {EMBO Molecular Medicine},
  number    = {5},
  doi       = {10.15252/emmm.202013548},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239018},
  year      = {2021},
  abstract  = {Lipids are the most energy-dense components of the diet, and their overconsumption promotes obesity and diabetes. Dietary fat content has been linked to the lipid processing activity by the intestine and its overall capacity to absorb triglycerides (TG). However, the signaling cascades driving intestinal lipid absorption in response to elevated dietary fat are largely unknown. Here, we describe an unexpected role of the protein kinase D2 (PKD2) in lipid homeostasis. We demonstrate that PKD2 activity promotes chylomicron-mediated TG transfer in enterocytes. PKD2 increases chylomicron size to enhance the TG secretion on the basolateral side of the mouse and human enterocytes, which is associated with decreased abundance of APOA4. PKD2 activation in intestine also correlates positively with circulating TG in obese human patients. Importantly, deletion, inactivation, or inhibition of PKD2 ameliorates high-fat diet-induced obesity and diabetes and improves gut microbiota profile in mice. Taken together, our findings suggest that PKD2 represents a key signaling node promoting dietary fat absorption and may serve as an attractive target for the treatment of obesity.},
  language  = {en}
}
@article{HankirRotzingerNordbecketal.2021,
  author    = {Hankir, Mohammed K. and Rotzinger, Laura and Nordbeck, Arno and Corteville, Caroline and Dischinger, Ulrich and Knop, Juna-Lisa and Hoffmann, Annett and Otto, Christoph and Seyfried, Florian},
  title     = {Leptin receptors are not required for Roux-en-Y gastric bypass surgery to normalize energy and glucose homeostasis in rats},
  series = {Nutrients},
  volume    = {13},
  journal   = {Nutrients},
  number    = {5},
  issn      = {2072-6643},
  doi       = {10.3390/nu13051544},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239550},
  year      = {2021},
  abstract  = {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.},
  language  = {en}
}
@article{PlassmeierHankirSeyfried2021,
  author    = {Plassmeier, Lars and Hankir, Mohammed K. and Seyfried, Florian},
  title     = {Impact of Excess Body Weight on Postsurgical Complications},
  series = {Visceral Medicine},
  volume    = {37},
  journal   = {Visceral Medicine},
  number    = {4},
  issn      = {2297-4725},
  doi       = {10.1159/000517345},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-244890},
  pages     = {287-97},
  year      = {2021},
  abstract  = {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.},
  language  = {en}
}