University of Erlangen Medical Center

Erlangen, Germany

University of Erlangen Medical Center

Erlangen, Germany
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Fiegel H.C.,University of Leipzig | Pryymachuk G.,University of Erlangen Medical Center | Rath S.,National University of Singapore | Bleiziffer O.,University of Erlangen Medical Center | And 7 more authors.
Journal of Cellular and Molecular Medicine | Year: 2010

The use of foetal liver cells (FLC) in the context of hepatic tissue engineering might permit efficient in vitro expansion and cryopreservation in a cell bank. A prerequisite for successful application of bioartificial liver tissue is sufficient initial vascularization. In this study, we evaluated the transplantation of fibrin gel-immobilized FLC in a vascularized arterio-veno-venous (AV)-loop model. FLC were isolated from embryonic/foetal (ED 16) rat livers and were enriched by using magnetic cell sorting (MACS). After cryopreservation, FLC were labelled by pkh-26. Cells were transplanted in a fibrin matrix into a subcutaneous chamber containing a microsurgically created AV-loop in the femoral region of the recipient rat. The chambers were explanted after 14 days. Subcutaneous implants without an AV-loop and cell-free implants served as controls. Fluorescence microscopy of the constructs was used to identify pkh-26+- donor cells. Characterization was performed by RT-PCR and immunhistology (IH) for CK-18 and CD31. Transplantation of FLC using the AV-loop permitted a neo-tissue formation in the fibrin matrix. A high-density vascularization was observed in the AV-loop constructs as shown by CD31 IH. Viable foetal donor cells were detected which expressed CK-18. FLC can be successfully used for heterotopic transplantation. Fibrin matrix permits rapid blood vessel ingrowth from the AV-loop and supports engraftment of FLC. It is therefore an appropriate environment for hepatocyte transplantation in combination with microsurgical vascularization strategies. Transplantation of fibrin gel-immobilized FLC may be a promising approach for the development of highly vascularized in vivo tissue-engineering-based liver support systems. © 2008 The Authors Journal compilation © 2010 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.

Momeni A.,Stanford University | Goerke S.M.,Albert Ludwigs University of Freiburg | Bannasch H.,Albert Ludwigs University of Freiburg | Arkudas A.,University of Erlangen Medical Center | Stark G.B.,Albert Ludwigs University of Freiburg
Annals of Plastic Surgery | Year: 2013

Background: The importance of providing high-quality exposure and training in aesthetic and reconstructive surgery during residency has come to the forefront of plastic surgery education. Adequate training in aesthetic surgery, however, has traditionally been challenging. The authors were interested in how these challenges were met abroad. Methods: A 17-item online survey was developed to assess the quality of training in aesthetic surgery in Germany. The survey had 3 distinct sections: demographic information, current state of aesthetic surgery training, and residents' opinions about the perceived quality of aesthetic surgery training. Only responses of senior residents were included in the final analysis. Results: A total of 112 residents responded (30% response rate), of which 88 were senior plastic surgery residents. Ninety percent (n = 79) reported that a resident aesthetic surgery clinic was not part of their training experience. Eighty-eight percent (n = 77) reported that they did not have a dedicated aesthetic surgery rotation during their residency training. According to 69.3% (n = 61), no didactic training in aesthetic surgery was provided. Fifty-six percent (n = 49) of senior plastic surgery residents had performed only a maximum of 10 aesthetic surgery procedures at the time of the survey. Although only 43.2% of senior residents claimed to be interested in a predominantly aesthetic surgery practice, 90.9% (n = 80) felt that they require further training in aesthetic surgery (ie, fellowship). Conclusions: Deficiencies exist with respect to aesthetic surgery training among senior plastic surgery residents in Germany. Structural improvements in residency training with formal exposure and teaching in aesthetic surgery are warranted. The German Society of Plastic, Reconstructive and Aesthetic Surgeons is actively addressing deficiencies identified with the goal of improving the quality of training. © 2012 by Lippincott Williams and Wilkins.

Zugor V.,St Antonius Hospital | Labanaris A.P.,Martha Maria Medical Center | Witt J.,St Antonius Hospital | Seidler A.,Bamberg Medical Center | And 2 more authors.
Anticancer Research | Year: 2010

Background: Granulosa cell tumor of the testis is a rare intermediate stromal cell tumor that can be distinguished in the adult and juvenile type. The juvenile type is the most common reason for scrotal swelling in newborns under the age of six months. Less than fifty cases of this disease entity have been reported in the literature. Patients and Methods: In the following article, two newborn patients with scrotal swelling and a histological confirmation of juvenile granulosa cell tumor of the testis will be presented. Results: Case 1: A newborn patient presented with massive scrotal swelling. Sonography of the testicle exhibited a multiple septic and cystic enlargement of the testicle without distinction of the testicular parenchyma being possible. The laboratory findings demonstrated normal testosterone levels, β-HCG and inhibin-B levels as well as an increased alpha-fetoprotein level of 35.350 ng/dl. Due to clinical and sonographic findings, an inguinal exploration and later, due to the impossibility of distinction of the testicular parenchyma, an inguinal orchiectomy of the right testicle was performed. Case 2: The clinical and sonographic examination of a newborn patient demonstrated a suspicious process of the left testicle. Sonography exhibited an enlarged testicle with cystic formations with the distinction of the testicular parenchyma not being possible. The laboratory findings demonstrated normal testosterone levels, β-HCG and inhibin-B levels as well as an increased alpha-fetoprotein level of 9.038 ng/dl and LDH of 768 U/I. An inguinal orchiectomy of the left testicle was performed. In both cases, a histological diagnosis of juvenile granulosa cell tumor of the testis was made. Conclusion: These two aforementioned cases demonstrate that juvenile granulosa cell tumor of the testis is a benign disease encountered in newborns, which exhibits an excellent prognosis. Inguinal orchiectomy is the therapy of choice. After surgical removal of the involved testicle is performed no further management is required.

Schauer C.,Friedrich - Alexander - University, Erlangen - Nuremberg | Janko C.,Friedrich - Alexander - University, Erlangen - Nuremberg | Munoz L.E.,Friedrich - Alexander - University, Erlangen - Nuremberg | Zhao Y.,Friedrich - Alexander - University, Erlangen - Nuremberg | And 14 more authors.
Nature medicine | Year: 2014

Gout is characterized by an acute inflammatory reaction and the accumulation of neutrophils in response to monosodium urate (MSU) crystals. Inflammation resolves spontaneously within a few days, although MSU crystals can still be detected in the synovial fluid and affected tissues. Here we report that neutrophils recruited to sites of inflammation undergo oxidative burst and form neutrophil extracellular traps (NETs). Under high neutrophil densities, these NETs aggregate and degrade cytokines and chemokines via serine proteases. Tophi, the pathognomonic structures of chronic gout, share characteristics with aggregated NETs, and MSU crystals can induce NETosis and aggregation of NETs. In individuals with impaired NETosis, MSU crystals induce uncontrolled production of inflammatory mediators from neutrophils and persistent inflammation. Furthermore, in models of neutrophilic inflammation, NETosis-deficient mice develop exacerbated and chronic disease that can be reduced by adoptive transfer of aggregated NETs. These findings suggest that aggregated NETs promote the resolution of neutrophilic inflammation by degrading cytokines and chemokines and disrupting neutrophil recruitment and activation.

Horch R.E.,University of Erlangen Medical Center | D'Hoore A.,University Clinics Gasthuisberg | Holm T.,Karolinska University Hospital | Kneser U.,University of Erlangen Medical Center | And 2 more authors.
Annals of Surgical Oncology | Year: 2012

Background: In our own experience over the last 15 years, the primary transpelvic vertical rectus abdominis myocutaneous (VRAM) flap is a reliable tool to prevent perineal wound complications after cylindrical excision in radical anorectal tumor surgery. To minimize the operative trauma in such patients, we performed a laparoscopic abdominoperineal resection combined with an open posterior cylindrical excision and a primary transpelvic vertical rectus abdominis myocutaneous (VRAM) flap via a minimal supraumbilical incision, which is described here for the first time. Methods: A 49-year-old patient with recurrent anal cancer received radiochemotherapy with curative intention and underwent laparoscopic abdominoperineal rectal excision with posterior cylindrical excision combined with a primary transpelvic vertical rectus abdominis myocutaneous (VRAM) flap. The rectal stump was clipped and pulled through the pelvis together with the VRAM flap, which was then placed into the sacral defect. Results: We found that the combined operative technical approaches with laparoscopy and minimal incisions for flap harvest and cylindrical excision were technically feasible, and no mesh was needed to close the small-sized laparotomies. We achieved complete tumor removal and flap perfusion, and healing was uneventful. The patient showed no relapse at 3 years postoperative. Conclusions: Our report of the operative technique shows that the combination of minimally invasive methods together with transpelvic VRAM flap transposition is technically feasible, can be performed with operative efficiency, and may become a valuable tool to minimize perioperative complications in advanced colorectal tumor surgery. © 2011 Society of Surgical Oncology.

Kneser U.,University of Erlangen Medical Center | Brockmann S.,University of Erlangen Medical Center | Leffler M.,University of Erlangen Medical Center | Haeberle L.,Friedrich - Alexander - University, Erlangen - Nuremberg | And 5 more authors.
Journal of Plastic, Reconstructive and Aesthetic Surgery | Year: 2011

Background: Skin defects of the foot, ankle and distal lower leg often require coverage by local or distant flaps. We aimed to compare functional outcome and donor-site morbidity following transfer of distally based delayed sural (DSFs) or peroneus brevis flaps (PBFs). Methods: Between 2003 and 2006, 52 patients (24 DSFs and 28 PBFs) were included. For increased reliability, all extended sural flaps were delayed for 3-15 days. At the end of the follow-up period (minimum 12 months), patients were asked to fill out a modified foot and ankle score (Foot and Ankle Outcome Score (FAOS)) questionnaire. In addition, a chart review and a physical examination were performed. Results: Total hospital stay and total number of operations were significantly lower in the PBF group. Minor flap necrosis (<10%) was observed in 21% of the DSF and 7% of the PBF group, and partial (>10%) or total flap loss occurred in one and three patients from the DSF group, respectively. Patient satisfaction, FAOS results and range of motion were comparable in both groups. Defect aetiology and patient age did not influence surgical outcome. Conclusion: Donor-site morbidity and functional outcome after DSF and PBF are comparable. A higher rate of complications was observed in the DSF group. Based on our findings, the PBF is recommended as first-line procedure for reconstruction of small- to medium-sized defects at the distal tibia, fibula, ankle and heel. The sural flap might be chosen for extended skin defects especially when a larger arc of rotation is required. © 2010 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Zugor V.,St Antonius Hospital | Schott G.E.,University of Erlangen Medical Center | Lausen B.,University of Erlangen Medical Center | Kuhn R.,Martha Maria Medical Center | Labanaris A.P.,Martha Maria Medical Center
Anticancer Research | Year: 2010

Background: Although the NWTSG and SIOP studies have included the largest number of patients, several individual institutions have made likewise important contributions to the optimization of Wilms' tumor therapy. The purpose of this study is to present our personal experience obtained in the last 42 years by treating Wilms' tumor in childhood. Patients and Methods: Throughout the period 1965-2006, 65 children with histological confirmation of Wilms' tumour were treated in the Department of Urology, University of Erlangen Medical Centre. The records of all patients presenting to our institution with Wilms' tumour were examined. Results: The results obtained by this study group indicate that prognosis according to age demonstrated no significance, but prognosis according to tumor size, lymph node involvement and distant metastasis was significant. After a 10-year follow-up, our data revealed an 89.4% survival rate. Furthermore, the statistical evaluation performed in order to evaluate the significance of surgical complications following neoadjuvant therapy in comparison to non adjuvant therapy, indicates that there is a significant increase in complications in patients who are not treated with neoadjuvant therapy. Discussion: Although clinicians in the USA. and Europe have different philosophies on preoperative chemotherapy, most patients with Wilms' tumor survive long term, regardless of the sequence of therapeutic interventions. In the absence of a clear choice between up-front nephrectomy and preoperative chemotherapy, it is reasonable to base the timing of resection on factors such as tumor size, the patient's clinical condition, and the experience of the surgeon.

Meng D.,Imperial College London | Rath S.N.,University of Erlangen Medical Center | Mordan N.,University College London | Salih V.,University College London | And 3 more authors.
Journal of Biomedical Materials Research - Part A | Year: 2011

Highly porous (>90% porosity) 45S5 Bioglass®-derived glass-ceramic scaffolds were fabricated by foam replication method, and coated with carbon nanotubes (CNT) (coating thickness: 1 μm) using electrophoretic deposition (EPD). In vitro cell culture using mesenchymal stem cells (MSCs) was carried out on both scaffold systems (with and without CNT coating) over a 4-week period. By using AlamarBlue ™, BSA and alkaline phosphatase assays; the cell viability and differentiation were measured quantitatively measured and compared between the two scaffold types. The results showed that both scaffold systems are biocompatible with MSCs and they can support the cellular activity. No cytotoxic effects of CNT were observed under the conditions of the present experiments. Although a lower initial cell viability on the CNT-coated scaffolds was observed, no significant differences were found after 4 weeks of culture compared with the uncoated scaffolds. This work therefore shows that there is in principle no significant improvement of cellular responses by creating a CNT-coating on this type of highly bioactive scaffolds. However, the electrical conductivity introduced by the coating might have the potential to increase cell viability and differentiation when cell culture is carried out under the effect of electrical stimulation. © 2011 Wiley Periodicals, Inc.

Arkudas A.,University of Erlangen Medical Center | Balzer A.,University of Erlangen Medical Center | Buehrer G.,University of Erlangen Medical Center | Arnold I.,University of Erlangen Medical Center | And 9 more authors.
Tissue Engineering - Part C: Methods | Year: 2013

In this study, the angiogenetic effect of sintered 45S5 Bioglass ® was quantitatively assessed for the first time in the arteriovenous loop (AVL) model. An AVL was created by interposition of a venous graft from the contralateral side between the femoral artery and vein in the medial thigh of eight rats. The loop was placed in a Teflon isolation chamber and was embedded in a sintered 45S5 Bioglass® granula matrix filled with fibrin gel. Specimens were investigated 3 weeks postoperatively by means of microcomputed tomography, histological, and morphometrical techniques. All animals tolerated the operations well. At 3 weeks, both microcomputed tomography and histology demonstrated a dense network of newly formed vessels originating from the AVL. All constructs were filled with cell-rich, highly vascularized connective tissue around the vascular axis. Analysis of vessel diameter revealed constant small vessel diameters, indicating immature new vessel sprouts. This study shows for the first time axial vascularization of a sintered 45S5 Bioglass® granula matrix. After 3 weeks, the newly generated vascular network already interfused most parts of the scaffolds and showed signs of immaturity. The intrinsic type of vascularization allows transplantation of the entire construct using the AVL pedicle. © 2013, Mary Ann Liebert, Inc.

Kneser U.,University of Erlangen Medical Center | Beier J.P.,University of Erlangen Medical Center | Dragu A.,University of Erlangen Medical Center | Arkudas A.,University of Erlangen Medical Center | Horch R.E.,University of Erlangen Medical Center
Journal of Plastic, Reconstructive and Aesthetic Surgery | Year: 2011

Propeller perforator flaps supplied by branches from the transverse cervical artery allow transport of skin from the back region to supraclavicular defects. This article describes a soft tissue defect following resection of melanoma metastasis that was successfully reconstructed using a propeller flap based on a perforator originating from the anterior part of the cranial trapezius muscle. This technique should be considered as an alternative to commonly used muscle or myocutanous flaps in selected cases. © 2010 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

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