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Dive into the research topics where Ulrich Mittelkötter is active.

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Featured researches published by Ulrich Mittelkötter.


Hpb Surgery | 2010

Indications and early outcomes for total pancreatectomy at a high-volume pancreas center.

M Janot; Orlin Belyaev; Sabine Kersting; Ansgar M. Chromik; Matthias H. Seelig; Dominique Sülberg; Ulrich Mittelkötter; Waldemar Uhl

Background. This study aimed to analyse the most common current indications for total pancreatectomy (TP) at a high-volume pancreas center. Method. Prospectively collected data on indications and short-term outcome of all TPs performed from January 2004 until June 2008 were analysed. Results. The total pancreatectomies (TP) were 63, i.e., 6.7% of all pancreatic procedures (n = 948). Indications for TP were classified into 4 groups: tumors of advanced stage, n = 23 (36.5%), technical problems due to soft pancreatic tissue, n = 18 (28.6%), troubles due to perioperative surgical complications, n = 15 (23.8%), and therapy-resistant pain due to chronic pancreatitis, n = 7 (11.1%). Surgical complications occurred in 23 patients (36.5%). The mortality in elective TP was 6.25%. Median postoperative stay was 21 days. Mortality, morbidity and the other perioperative parameters differed substantially according to the indication for pancreatectomy. Conclusion. Total pancreatectomy is definitely indicated for a limited range of elective and emergency situations. Indications can be: size or localisation of pancreatic tumor, trouble, technical diffuculties and therapy-refractory pain in chronic pancreatitis. A TP due to perioperative complications (troubles) after pancreatic resections is doomed by extremely high morbidity and mortality and should be avoided.


Journal of Clinical Gastroenterology | 2009

Bacteribilia after preoperative bile duct stenting: a prospective study.

Torsten Herzog; Orlin Belyaev; Christophe A. Müller; Ulrich Mittelkötter; Matthias H. Seelig; Dirk Weyhe; Peter Felderbauer; Renate Schlottmann; Henning Schrader; Wolfgang Schmidt; Waldemar Uhl

Study Design A prospective analysis of intraoperative bile duct cultures in patients undergoing surgery for both, malignant or benign periampullary diseases at the Department of Surgery, St Josef Hospital, Bochum, Germany, during a period of 18 months, between January 2004 and June 2005. Goals The goals of the presented study were to investigate the effects of preoperative bile duct stenting on intraoperative bile duct cultures and postoperative outcome in patients undergoing pancreatic surgery. Background In pancreatic surgery, bile duct stenting is often aimed at improving postoperative outcome. As implantation of xenograft material in the main bile duct facilitates bacterial contamination and cholangitis, a critical evaluation of stenting is mandatory. Study In all patients with a hepaticojejunostomy (n=80), a bile duct culture was collected during the operation. All patients received antibiotic prophylaxis perioperatively and a retrograde flushing of bile ducts with warm saline after bile duct resection. Fifty-one percent (41/80) patients had biliary drainage before surgery, whereas 49% (39/80) were operated without preoperative draining procedures. Results After bile duct stenting, 98% of patients had a positive bile culture, whereas only 21% of infected bile was seen in patients without drainage (P<0.001). Despite infected bile, only 2% stented patients developed acute cholangitis postoperatively, versus 13% patients in the group without stent (P=0.231). After stenting, major complications occurred in 12%, versus 8% in patients without stent (P=0.817). Conclusions Preoperative biliary drainage leads to an almost 100% bacterial contamination of bile ducts. With hospital-adjusted antibiotic prophylaxis and retrograde flushing of bile ducts, the postoperative rate of acute cholangitis and morbidity is not elevated. A critical evaluation of benefits from preoperative biliary drainage for each patient is necessary.


International Journal of Oncology | 1992

Synergistic apoptotic effects of taurolidine and TRAIL on squamous carcinoma cells of the esophagus

Adrien Daigeler; Ansgar M. Chromik; A. Geisler; Daniel Bulut; Christoph Hilgert; Andreas Krieg; Ludger Klein-Hitpass; Marcus Lehnhardt; Waldemar Uhl; Ulrich Mittelkötter

The treatment of choice for esophageal cancer is considered surgical resection, but a median survival of around 20 months after treatment is still discouraging. The value of adjuvant or neoadjuvant radiation or chemotherapy is limited and to date, benefits have only been described for certain tumor stages. Therefore, new therapeutic options are required. As alternative chemotherapeutics, we tested the antibiotic taurolidine (TRD) on KYSE 270 human esophageal carcinoma cells alone and in combination with rhTRAIL (TNF related apoptosis-inducing ligand). Viability, apoptosis and necrosis were visualized by TUNEL assay and quantitated by FACS analysis. Gene expression was analysed by RNA microarray. The most effective concentration of TRD as single substance (250 micromol/l) induced apoptosis to a maximum of 40% after 12-h dose dependently, leaving 4% viable cells after 48 h; by comparison, rhTRAIL did not have a significant effect. The combination of both substances doubled the effect of TRD alone. Gene expression profiling revealed that TRD downregulated endogenous TRAIL, TNFRSF1A, TRADD, TNFRSF1B, TNFRSF21, FADD, as well as MAP2K4, JAK2 and Bcl2, Bcl2l1, APAF1 and caspase-3. TNFRSF25, cytochrome-c, caspase-1, -8, -9, JUN, GADD45A and NFKBIA were upregulated. TRAIL reduced endogenous TRAIL, Bcl2l1 and caspase-1 expression. BIRC2, BIRC3, TNFAIP3, and NFKBIA were upregulated. The combined substances upregulated endogenous TRAIL, NFKBIA and JUN, whereas DFFA and TRAF3 were downregulated compared to TRD as single substance. We conclude that TRD overcomes TRAIL resistance in KYSE 270 cells. Synergistic effects are dependent on the same and on distinct apoptotic pathways which, jointly triggered, result in an amplified response. Several apoptotic pathways, including the TNF-receptor associated and the mitochondrial pathway, were differentially regulated by the substances on gene expression level. Additionally transcription factors seem to be influenced, NFKB in particular. Endogenous TRAIL expression is increased by the combination of substances, whereas it is reduced by each single substance. Taking into consideration that the non-toxic TRD was able to reduce rhTRAIL toxicity and dose, combined therapy with TRD and rhTRAIL may offer new options for treatment in esophageal cancer.


Journal of Investigative Surgery | 2007

Genetic Deletion of JNK1 and JNK2 Aggravates the DSS-Induced Colitis in Mice

Ansgar M. Chromik; Annette M. Müller; J. Körner; Orlin Belyaev; T. Holland-Letz; Frank Schmitz; Thomas Herdegen; Waldemar Uhl; Ulrich Mittelkötter

The c-Jun N-terminal kinases (JNKs) are considered as novel targets for therapy of inflammatory bowel diseases (IBD). However, the relevant JNK isoforms have to be elucidated. Here, we analyze the individual contribution of the JNK1 and JNK2 isoforms in a dextran sulfate sodium (DSS) model of experimental colitis. JNK1 and JNK2 knockout mice (JNK1 ko, JNK2 ko) and their wild-type controls (WT1, WT2) received three cycles of DSS treatment, each consisting of 1.7% DSS for 5 days, followed by 5 days with water. Animals were daily evaluated by a disease activity index (DAI) comprising measurement of body weight, estimation of stool consistency, and test for occult blood/gross rectal bleeding. After 30 days all animals were sacrificed, and the inflamed intestine was histologically evaluated by a crypt damage score. Unexpectedly, neither JNK1 ko nor JNK2 ko prevented mice from developing a chronic colitis when compared to wild-type controls WT1 and WT2, respectively. On the contrary, DAI and mortality were aggravated in JNK2 ko compared to WT2. DAI and mortality did not differ between JNK1 ko and WT1, but the histological crypt damage score was significantly enhanced in the cecum of JNK1 ko mice. Genetic deletion of JNK2 worsens the disease outcome in an experimental model of murine colitis. We hypothesize that the functional deletion of the otherwise proapoptotic JNK2 prolongs the activity of proinflammatory immune cells with deterioration of disease activity.


Journal of Experimental & Clinical Cancer Research | 2008

TRAIL and Taurolidine induce apoptosis and decrease proliferation in human fibrosarcoma

Adrien Daigeler; Christina Brenzel; Daniel Bulut; A. Geisler; Christoph Hilgert; Marcus Lehnhardt; Hans Ulrich Steinau; Annegret Flier; Lars Steinstraesser; Ludger Klein-Hitpass; Ulrich Mittelkötter; Waldemar Uhl; Ansgar M. Chromik

BackgroundDisseminated soft tissue sarcoma still represents a therapeutic dilemma because effective cytostatics are missing. Therefore we tested TRAIL and Tarolidine (TRD), two substances with apoptogenic properties on human fibrosarcoma (HT1080).MethodsViability, apoptosis and necrosis were visualized by TUNEL-Assay and quantitated by FACS analysis (Propidiumiodide/AnnexinV staining). Gene expression was analysed by RNA-Microarray and the results validated for selected genes by rtPCR. Protein level changes were documented by Western Blot analysis. NFKB activity was analysed by ELISA and proliferation assays (BrdU) were performed.Results and discussionThe single substances TRAIL and TRD induced apoptotic cell death and decreased proliferation in HT1080 cells significantly. Gene expression of several genes related to apoptotic pathways (TRAIL: ARHGDIA, NFKBIA, TNFAIP3; TRD: HSPA1A/B, NFKBIA, GADD45A, SGK, JUN, MAP3K14) was changed. The combination of TRD and TRAIL significantly increased apoptotic cell death compared to the single substances and lead to expression changes in a variety of genes (HSPA1A/B, NFKBIA, PPP1R15A, GADD45A, AXL, SGK, DUSP1, JUN, IRF1, MYC, BAG5, BIRC3). NFKB activity assay revealed an antipodal regulation of the several subunits of NFKB by TRD and TRD+TRAIL compared to TRAIL alone.ConclusionTRD and TRAIL are effective to induce apoptosis and decrease proliferation in human fibrosarcoma. A variety of genes seems to be involved, pointing to the NFKB pathway as key regulator in TRD/TRAIL-mediated apoptosis.


Journal of Experimental & Clinical Cancer Research | 2010

Comparative analysis of cell death induction by Taurolidine in different malignant human cancer cell lines

Ansgar M. Chromik; Adrien Daigeler; Daniel Bulut; Annegret Flier; Christina May; Kamran Harati; Jan Roschinsky; Dominique Sülberg; Peter R. Ritter; Ulrich Mittelkötter; Stephan A. Hahn; Waldemar Uhl

BackgroundTaurolidine (TRD) represents an anti-infective substance with anti-neoplastic activity in many malignant cell lines. So far, the knowledge about the cell death inducing mechanisms and pathways activated by TRD is limited. The aim of this study was therefore, to perform a comparative analysis of cell death induction by TRD simultaneously in different malignant cell lines.Materials and methodsFive different malignant cell lines (HT29/Colon, Chang Liver/Liver, HT1080/fibrosarcoma, AsPC-1/pancreas and BxPC-3/pancreas) were incubated with increasing concentrations of TRD (100 μM, 250 μM and 1000 μM) for 6 h and 24 h. Cell viability, apoptosis and necrosis were analyzed by FACS analysis (Propidiumiodide/AnnexinV staining). Additionally, cells were co-incubated with the caspase Inhibitor z-VAD, the radical scavenger N-Acetylcystein (NAC) and the Gluthation depleting agent BSO to examine the contribution of caspase activation and reactive oxygen species in TRD induced cell death.ResultsAll cell lines were susceptible to TRD induced cell death without resistance toward this anti-neoplastic agent. However, the dose response effects were varying largely between different cell lines. The effect of NAC and BSO co-treatment were highly different among cell lines - suggesting a cell line specific involvement of ROS in TRD induced cell death. Furthermore, impact of z-VAD mediated inhibition of caspases was differing strongly among the cell lines.ConclusionThis is the first study providing a simultaneous evaluation of the anti-neoplastic action of TRD across several malignant cell lines. The involvement of ROS and caspase activation was highly variable among the five cell lines, although all were susceptible to TRD induced cell death. Our results indicate, that TRD is likely to provide multifaceted cell death mechanisms leading to a cell line specific diversity.


Journal of Investigative Surgery | 2007

Synergistic Effects in Apoptosis Induction by Taurolidine and TRAIL in HCT-15 Colon Carcinoma Cells

Ansgar M. Chromik; Adrien Daigeler; Christoph Hilgert; Daniel Bulut; A. Geisler; V. Liu; Jan-Michel Otte; Waldemar Uhl; Ulrich Mittelkötter

Induction of apoptosis in tumor cells by TRAIL (tumor necrosis factor [TNF]-related apoptosis-inducing ligand) is a promising therapeutic principle in oncology, although toxicity and resistance against TRAIL are limiting factors. Taurolidine (TRD), an antineoplastic agent with low toxicity, is a potential candidate for combined therapy with TRAIL. The aim of this study was to evaluate the apoptotic effects of a combined treatment with TRD and TRAIL in a human HCT-15 colon carcinoma cell line. HCT-15 cells were incubated with increasing concentrations of recombinant human TRAIL (50 ng/mL to 500 ng/mL) or TRD (50 μ mol/L to 1000 μ mol/L). In a second experiment, cells were furthermore exposed to a combination of both substances (TRAIL 50 ng/mL and TRD 100 μ mol/L). At various time points (3 h to 36 h), cell viability, apoptosis, and necrosis were quantified by FACS analysis (propidium iodide/annexin V-FITC) and confirmed by TUNEL assay. Incubation with TRD resulted in cell death induction with maximum effects observed at 100 μ mol/L and 1000 μ mol/L after 36 h. TRAIL application led to dose-dependent cell death induction as early as 6 h. Combined treatment of TRD (100 μ mol/L) and TRAIL (50 ng/mL) caused a sustained induction of apoptosis that was superior to single-agent application, exceeding a merely additive effect. Combinatory treatment of human colon carcinoma cells with TRD and TRAIL results in a synergistic effect on apoptosis induction with a significant increase of the apoptotic index. Combination of TRAIL with the nontoxic TRD might represent a novel therapeutic strategy in oncological therapy.


Journal of Inflammation Research | 2013

Knockout of the c-Jun N-terminal Kinase 2 aggravates the development of mild chronic dextran sulfate sodium colitis independently of expression of intestinal cytokines TNFα, TGFB1, and IL-6

Sabine Kersting; Kirstin Reinecke; Christoph Hilgert; M Janot; Elisabeth Haarmann; Martin Albrecht; Annette M. Müller; Thomas Herdegen; Ulrich Mittelkötter; Waldemar Uhl; Ansgar M. Chromik

Introduction The c-Jun N-terminal kinases (JNKs) are involved in signal transduction of inflammatory bowel diseases. The aim of this study was to examine the function of JNKs by using a low-dose dextran sulfate sodium (DSS) model in JNK1 knockout mice (Mapk8−/−), JNK2 knockout mice (Mapk9−/−), and wild-type controls (WT1, WT2). Methods The animals were evaluated daily using a disease activity index. After 30 days, the intestine was evaluated histologically with a crypt damage score. CD4+ and CD8+ cells were quantified using immunofluorescence. Analysis of tumor necrosis factor-α (TNFα), interleukin-6 (IL-6), and transforming growth factor β1 (TGFB1) expression was carried out using LightCycler® real-time polymerase chain reaction. Results Cyclic administration of low-dose DSS (1%) was not able to induce features of chronic colitis in Mapk8−/− WT2 mice. By contrast, DSS administration significantly increased the disease activity index in WT1 and Mapk9−/− mice. In Mapk9−/− mice, the crypt damage score and the number of CD4+ and CD8+ cells as features of chronic colitis/inflammation were also significantly elevated. Expression of TNFα, IL-6, and TGFB1 was not altered by the JNK knockout. Conclusion Administering DSS at a defined low concentration that is unable to induce colitis in WT animals leads to clinically and histologically detectable chronic colitis in Mapk9−/− mice. The reason for this disease-inducing effect resulting from the loss of JNK2 remains to be elucidated. Expression of TNFα, IL-6, and TGFB1 does not appear to be involved; proapoptotic JNK2 may prolong the activity of proinflammatory immune cells, leading to perpetuation of the inflammation.


BMC Cancer | 2010

Gene expression analysis of cell death induction by Taurolidine in different malignant cell lines

Ansgar M. Chromik; Stephan A. Hahn; Adrien Daigeler; Annegret Flier; Daniel Bulut; Christina May; Kamran Harati; Jan Roschinsky; Dominique Sülberg; Dirk Weyhe; Ulrich Mittelkötter; Waldemar Uhl

BackgroundThe anti-infective agent Taurolidine (TRD) has been shown to have cell death inducing properties, but the mechanism of its action is largely unknown. The aim of this study was to identify potential common target genes modulated at the transcriptional level following TRD treatment in tumour cell lines originating from different cancer types.MethodsFive different malignant cell lines (HT29, Chang Liver, HT1080, AsPC-1 and BxPC-3) were incubated with TRD (100 μM, 250 μM and 1000 μM). Proliferation after 8 h and cell viability after 24 h were analyzed by BrdU assay and FACS analysis, respectively. Gene expression analyses were carried out using the Agilent -microarray platform to indentify genes which displayed conjoint regulation following the addition of TRD in all cell lines. Candidate genes were subjected to Ingenuity Pathways Analysis and selected genes were validated by qRT-PCR and Western Blot.ResultsTRD 250 μM caused a significant inhibition of proliferation as well as apoptotic cell death in all cell lines. Among cell death associated genes with the strongest regulation in gene expression, we identified pro-apoptotic transcription factors (EGR1, ATF3) as well as genes involved in the ER stress response (PPP1R15A), in ubiquitination (TRAF6) and mitochondrial apoptotic pathways (PMAIP1).ConclusionsThis is the first conjoint analysis of potential target genes of TRD which was performed simultaneously in different malignant cell lines. The results indicate that TRD might be involved in different signal transduction pathways leading to apoptosis.


Journal of Pediatric Surgery | 2008

Tailored resective pancreatic surgery for pediatric patients with chronic pancreatitis

Ansgar M. Chromik; Matthias H. Seelig; Benjamin Saewe; Christophe Müller; Dirk Weyhe; Peter Felderbauer; Ulrich Mittelkötter; Andrea Tannapfel; Anjona Schmidt-Choudhury; Waldemar Uhl

BACKGROUND Surgical treatment for chronic pancreatitis (CP) in children comprises predominantly nonresective draining procedures. The purpose of this study was to identify indications, techniques, and results of organ-preserving resective pancreatic procedures for pediatric CP at our institution. PATIENTS AND METHODS A retrospective chart review was performed of all children undergoing pancreatic surgery for CP over a period of 4 years. RESULTS Overall, 6 pediatric patients (3 male, 3 female, ages 7-18 years) underwent a duodenum-preserving pancreatic head resection (3), a middle segmental pancreatic resection (2), or a distal pancreatectomy (1) for CP of different etiologies (idiopathic 2, posttraumatic 2, pancreas divisum 1, situs inversus 1). No mortality or major surgical complication occurred. Mean operative time was 294 min (207-412 min) and intraoperative blood loss was 541 mL (100-1300 mL). Postoperative hospital stay was 13 days (10-18 days). No endocrine or exocrine insufficiency occurred during follow up of 46 months (25-50 m), and pain control was improved in 5 of 6 patients. CONCLUSIONS Tailored organ-preserving resective pancreatic surgery can be performed with low morbidity and mortality in pediatric patients with CP and not responding to conservative treatment.

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A. Geisler

Ruhr University Bochum

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