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Dive into the research topics where A. Hirner is active.

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Featured researches published by A. Hirner.


Surgery | 1996

Surgical stress induces a shift in the type-1/type-2 T-helper cell balance, suggesting down-regulation of cell-mediated and up-regulation of antibody-mediated immunity commensurate to the trauma*

D. Decker; Martin Schöndorf; Frank Bidlingmaier; A. Hirner; Alexander von Ruecker

BACKGROUND Measuring serum cytokines, pituitary hormones, or acute phase proteins during or after surgery is not an optimal method for quantifying the impact of surgical procedures. In an effort to assess surgical stress by means of the immune response, we focused on changes in cell-mediated and antibody-mediated immunity as illustrated by the type 1/type 2 T-helper (Th1/Th2) cell balance. The sensitivity of this approach was evaluated by comparing laparoscopic and conventional cholecystectomy (LCE, CCE). METHODS In a pragmatic prospective study 43 patients with symptomatic cholelithiasis were operated on either by LCE (n = 25) or CCe (n = 18). Blood sampling was done 24 hours before surgery, immediately before incision, and 2, 24, and 48 hours after surgery. Cell surface markers and cytokine production were used to characterize the Th1/Th2 balance and were measured by means of flow cytometry and enzyme-linked immunosorbent assay techniques. RESULTS Activation of Th2 cells evokes the production and secretion of interleukin-4 (IL-4), which up-regulates the expression of immunoglobulin E receptors (Fo epsilon RII, CD23) on B cells. Phytohemagglutinin-induced IL-4 production in freshly isolated peripheral blood mononuclear cells from patients increased more after CCE than LCE (IL-4, +41% versus +17%; p < 0.05). Also the expression of CD23 on B cells was higher after CCE than LCE (+146% versus +63%; P < 0.01). CD30, a membrane molecule that belongs to the tumor necrosis factor receptor superfamily and probably is an important indicator of Th2 activity, was more evaluated on T cells from patients who underwent CCE. The Th1 response, characterized by phytohemagglutinin-induced IFN-gamma secretion in peripheral blood mononuclear cells and up-regulation of human leukocyte antigen-DR expression on monocytes, was lower after CCE than after LCE. CONCLUSIONS This study shows that surgical stress induces a shift in the Th1/Th2 balance toward Th2, suggesting that cell-mediated immunity is down-regulated and antibody-mediated immunity is up-regulated after surgery. The evaluation of this shift may be clinically meaningful and help quantify even less invasive surgical procedures. When comparing CCE and LCE in this not strictly randomized study, we found LCE to be the less stressful procedure.


Gut | 2007

Inhibition of macrophage function prevents intestinal inflammation and postoperative ileus in rodents

Sven Wehner; Florian F. Behrendt; Boris N Lyutenski; Mariola Lysson; Anthony J. Bauer; A. Hirner; Jörg C. Kalff

Background: Abdominal surgery results in a molecular and cellular inflammatory response in the intestine, leading to postoperative ileus. It was hypothesised that resident macrophages within the intestinal muscularis have an important role in this local inflammation. Aims: To investigate whether chemical or genetic depletion of resident muscularis macrophages would lead to a reduction in the local inflammation and smooth-muscle dysfunction. Methods: Two rodent models were used to deplete and inactivate macrophages: (1) a rat model in which resident macrophages were depleted by chlodronate liposomes; (2) a model of mice with osteopetrosis mice, completely lacking the resident muscularis macrophages, used as an additional genetic approach. Animals with normal or altered intestinal macrophages underwent surgical intestinal manipulation. The inflammatory response was investigated by quantitative reverse transcriptase-polymerase chain reaction for mRNA of MIP-1α, interleukin (IL)1β, IL6, intracellular adhesion molecule 1 (ICAM-1) and monocyte chemotractant protein 1 (MCP)-1 in the isolated small bowel muscularis. In addition, muscularis whole mounts were used for histochemical and immunohistochemical analysis to quantify leucocyte infiltration and detect cytokine expression. Subsequently, in vitro muscle contractility and in vivo gastrointestinal transit were measured. Results: Both models resulted in markedly decreased expression of MIP-1α, IL1β, IL6, ICAM-1 and MCP-1 after manipulation compared with controls. In addition to this decrease in inflammatory mediators, recruitment of leucocytes into the muscularis was also diminished. Macrophage-altered animals had near normal in vitro jejunal circular muscle function and gastrointestinal transit despite surgical manipulation. Conclusions: Resident intestinal muscularis macrophages are initially involved in inflammatory responses resulting in postoperative ileus. Depletion and inactivation of the muscularis macrophage network prevents postoperative ileus.


Nature Medicine | 2010

T helper type 1 memory cells disseminate postoperative ileus over the entire intestinal tract

Daniel R. Engel; Arne Koscielny; Sven Wehner; Juliane Maurer; Lars Franken; Beatrix Schumak; Andreas Limmer; Tim Sparwasser; A. Hirner; Percy A. Knolle; Jörg C. Kalff; Christian Kurts

Localized abdominal surgery can lead to disruption of motility in the entire gastrointestinal tract (postoperative ileus). Intestinal macrophages produce mediators that paralyze myocytes, but it is unclear how the macrophages are activated, especially those in unmanipulated intestinal areas. Here we show that intestinal surgery activates intestinal CD103+CD11b+ dendritic cells (DCs) to produce interleukin-12 (IL-12). This promotes interferon-γ (IFN-γ) secretion by CCR9+ memory T helper type 1 (TH1) cells which activates the macrophages. IL-12 also caused some TH1 cells to migrate from surgically manipulated sites through the bloodstream to unmanipulated intestinal areas where they induced ileus. Preventing T cell migration with the drug FTY720 or inhibition of IL-12, T-bet (TH1-specific T box transcription factor) or IFN-γ prevented postoperative ileus. CCR9+ TH1 memory cells were detected in the venous blood of subjects 1 h after abdominal surgery. These findings indicate that postoperative ileus is a TH1 immune-mediated disease and identify potential targets for disease monitoring and therapy.


Surgical Endoscopy and Other Interventional Techniques | 2001

Use of the Polyflex stent in the palliative therapy ofesophageal carcinoma

P. Decker; J. Lippler; D. Decker; A. Hirner

Background:Several prospective randomized trials have shown that self-expanding stents have advantages over conventional plastic tubes. Nevertheless, the optimal stent has not yet been developed. The Polyflex stent is a completely new model that represents an improvement over the old metal stents. We have used this stent in a prospective study and herein our present preliminary results. Methods:In 14 patients with nonresectable esophageal carcinoma, the Polyflex stent was implanted to reduce dysphagia. The grade of dysphagia, the complications following intervention, and the patients’ total survival time were documented prospectively every 4 weeks. Results:The implantation of the stent was successful in all cases. The grade of the dysphagia was reduced from 3.0 to 0.5 after stent implantation. One patient died during the hospital stay from a non–stent-induced complication. Stent dislocation occurred once, and tumor overgrowth at the stent margins was observed twice. The mean survival time was 6.2 months, and the reintervention rate was 21.3%. Conclusion:The new Polyflex stent, which is based on a completely new design, can be implanted without any difficulty and has had very good shortand long-term results. Therefore, it is a worthy alternative to the metal stents in current use.


Langenbeck's Archives of Surgery | 2003

Current state of portosystemic shunt surgery

Martin Wolff; A. Hirner

BackgroundA switch to decompressive shunt procedures is mandatory if endoscopic therapy fails to control recurrent variceal hemorrhage. Surgical shunt procedures continue to be safe, highly effective, and durable procedures to treat variceal bleeding in patients with low operative risk and good liver function.DiscussionIn cirrhotics, elective operations using portal flow preserving techniques such as a selective distal splenorenal shunt (Warren) and a partial portocaval small diameter interposition shunt (Sarfeh) should be preferred. Rarely, end-to-side portocaval shunt may serve as a salvage procedure if emergency endoscopic treatment or transjugular intrahepatic portosystemic shunt insertion fails to stop bleeding. Until definitive results from randomized trials are available patients with good prognosis (Child-Pugh A and B) should be regarded as candidates for surgical shunts. For patients with noncirrhotic portal hypertension, in particular with extrahepatic portal vein thrombosis, portosystemic shunt surgery represents the only effective therapy which leads to freedom of recurrent bleeding and repeated endoscopies for many years, and improves hypersplenism without deteriorating liver function or encephalopathy. Gastroesophageal devascularization and other direct variceal ablative procedures should be restricted to treat endoscopic therapy failures without shuntable portal tributaries.


Liver Transplantation | 2009

Impaired autophagic clearance after cold preservation of fatty livers correlates with tissue necrosis upon reperfusion and is reversed by hypothermic reconditioning

Thomas Minor; Judith Stegemann; A. Hirner; Martina Koetting

Fatty livers are particularly susceptible to mitochondrial alterations after cold preservation. We thus aimed to improve graft integrity by brief hypothermic oxygenation prior to warm reperfusion. Macrovesicular steatosis was induced in rat livers by fasting and subsequent feeding of a fat‐free diet enriched with carbohydrates. Fatty livers were retrieved and stored ischemically at 4°C for 20 hours in histidine‐tryptophan‐ketoglutarate solution. Hypothermic reconditioning (HR) was performed in some livers by insufflation of gaseous oxygen via the caval vein during the last 90 minutes of preservation. Viability was assessed upon isolated reperfusion. HR resulted in a significant (approximately 5‐fold) reduction of parenchymal (alanine aminotransferase and lactate dehydrogenase) and mitochondrial (glutamate dehydrogenase) enzyme release. Functional recovery (bile production, oxygen consumption, and tissue levels of adenosine triphosphate) was significantly improved by HR. In untreated grafts, cellular autophagy (cleavage of LC3B and protein expression of beclin‐1) was significantly impaired (<50% of baseline) after preservation/reperfusion but was restored to normal values by HR. HR also increased cleavage of caspase 9 (P < 0.5) and caspase 3 enzyme activity (by a factor of 1.5). In contrast, histological signs of tissue necrosis were abundant after reperfusion in untreated livers and largely abrogated in reconditioned livers. In conclusion, HR limits mitochondrial defects and restores basal rates of cellular autophagy. This may represent a rescue mechanism for maintaining cellular homeostasis and tissue survival. Liver Transpl 15:798–805, 2009.


Gastroenterology | 2009

Inhibition of p38 mitogen-activated protein kinase pathway as prophylaxis of postoperative ileus in mice.

Sven Wehner; Stefan Straesser; Tim O. Vilz; Dimitrios Pantelis; Thais Sielecki; Vidal F. de la Cruz; A. Hirner; Joerg C. Kalff

BACKGROUND & AIMS Postoperative ileus, an iatrogenic complication of abdominal surgery, is mediated by severe inflammation of the tunica muscularis. Macrophages that reside in the muscularis have important roles in initiating the inflammation. We investigated whether activation of the p38 mitogen-activated protein kinase (MAPK) and stress-activated protein kinase is involved in the genesis of postoperative ileus, and whether p38-MAPK inhibition by the macrophage-specific inhibitor semapimod prevents intestinal dysmotility. METHODS Postoperative ileus was induced by intestinal manipulation of the small bowel in mice. Protein kinase phosphorylation was assessed by immunoblotting of muscularis externa preparations. Proinflammatory gene expression was quantified by real-time polymerase chain reaction. Myeloperoxidase histochemistry for neutrophils was performed in jejunal segments. Nitric oxide production was measured by Griess reaction in smooth-muscle organ culture supernatants. Jejunal contractility was assessed within an organ bath setup. Intestinal motility was analyzed by gastrointestinal and colonic transit measurements. RESULTS High levels of p38-MAPK and stress-activated protein kinase phosphorylation were observed immediately after intestinal manipulation. Semapimod treatment led to a significant decrease of p38-MAPK phosphorylation in macrophages; proinflammatory gene expression of macrophage inflammatory protein-1alpha, interleukin-6, monocyte chemoattractant protein-1, and intercellular adhesion molecule-1; and neutrophil infiltration. Furthermore, semapimod completely abrogated nitric oxide production within the tunica muscularis. Subsequently, semapimod prevented the suppression of smooth muscle contractility and small intestinal and colonic motility after intestinal manipulation. CONCLUSION A single preoperative semapimod administration prevents intestinal macrophage activation and subsequent gastrointestinal dysmotility induced by abdominal surgery. Semapimod inhibits p38-MAPK and nitric oxide production in macrophages, making it a promising strategy for prophylaxis of postoperative ileus.


World Journal of Surgical Oncology | 2003

Desmoid tumors of the abdominal wall: A case report

Marcus Overhaus; Pan Decker; Hans Fischer; Hj Textor; A. Hirner

BackgroundDesmoid tumors are slow growing deep fibromatoses with aggressive infiltration of adjacent tissue but without any metastatic potential.Case PresentationWe report on two female patients with desmoid tumor of the abdominal wall who underwent primary resection. Both patients had a history of an earlier abdominal surgery. Preoperative evaluation included abdominal ultrasound, magnetic resonance imaging and computed tomography. The histology in both cases revealed a desmoid tumor.ConclusionComplete surgical resection is the first line management of this tumor entity.


Journal of Gastrointestinal Surgery | 2009

Operative Re-intervention Following Pancreatic Head Resection: Indications and Outcome

Jens Standop; Tim R. Glowka; Volker Schmitz; Nico Schäfer; Marcus Overhaus; A. Hirner; Jörg C. Kalff

BackgroundThis study analyzed indication and outcome regarding operative re-intervention following pancreatoduodenectomy (PD) and pancreatogastrostomy (PG) with special emphasis on complications related to redo surgery.Patients and MethodsTwo hundred eighty-five patients who underwent PD with PG between 1989 and 2008 were identified from a pancreatic resection database and indications for repeat surgery were registered. Patients with and without reoperation were analyzed with regard to gender, age, underlying disease, length of hospital stay, mortality rate, and postoperative complications.ResultsThirty-one patients (11%) underwent operative reintervention. Early intra-abdominal extraluminal postoperative bleeding was the main cause for redo surgery followed by abdominal abscesses. Thirteen percent of patients with and 1.9% without secondary surgery died during the postoperative course. Forty-five percent of reoperated patients had to undergo at least one more operation resulting in doubling of the length of hospital stay. There was no correlation between patients’ gender, age, and underlying disease and the need for operative reintervention. However, redo surgery was associated with higher incidence of delayed gastric emptying, pancreatic fistula and bleeding, and non-surgery related complication. Intra-abdominal bleeding and abscesses, insufficiencies of bilio-digestive and gut anastomosis, wound infections, and pancreatitis were observed significantly more often in patients with secondary surgery.ConclusionsComplications after pancreatic resection that require operative re-intervention are associated with a notably increased mortality, ranging between 13% and 60%. Apart from the surgeon’s experience in selecting patients and his/her personal technical skills in performing a pancreaticoduodenectomy, timely anticipation and determined management of postoperative complications is essential for improving the outcome of this operation.


American Journal of Transplantation | 2007

Resident Macrophages are Involved in Intestinal Transplantation‐Associated Inflammation and Motoric Dysfunction of the Graft Muscularis

Nico Schaefer; K. Tahara; J. Schmidt; Sven Wehner; Jörg C. Kalff; Kareem Abu-Elmagd; A. Hirner; Andreas Türler

Gut manipulation and ischemia/reperfusion evoke an inflammatory response within the intestinal muscularis that contributes to dysmotility. We hypothesize that resident macrophages play a key role in initiating the inflammatory cascade. Isogenic small bowel transplantation was performed in Lewis rats. The impact of recovery of organs on muscularis inflammation was investigated by comparing cold whole‐body perfusion after versus prior to recovery. The role of macrophages was investigated by transplantation of macrophage‐depleted gut. Leukocytes were counted using muscularis whole mounts. Mediator expression was determined by real‐time RT‐PCR. Contractility was assessed in a standard organ bath. Both organ recovery and ischemia/reperfusion induced leukocyte recruitment and a significant upregulation in IL‐6, MCP‐1, ICAM‐1 and iNOS mRNAs. Although organ recovery in cold ischemia prevented early gene expression, peak expression was not changed by modification of the recovery technique. Compared to controls, transplanted animals showed a 65% decrease in smooth muscle contractility. In contrast, transplanted macrophage‐depleted isografts exhibited significant less leukocyte infiltration and only a 19% decrease in contractile activity. In summary, intestinal manipulation during recovery of organs initiates a functionally relevant inflammatory response within the intestinal muscularis that is massively intensified by the ischemia reperfusion injury. Resident muscularis macrophages participate in initiating this inflammatory response.

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R. Häring

Free University of Berlin

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Rene Tolba

RWTH Aachen University

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