@phdthesis{Koschitzki2020, author = {Koschitzki, Kim Christine Cornelia}, title = {Evaluation of preclinical animal models in bone tissue engineering and their success in clinical translation}, doi = {10.25972/OPUS-20759}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-207593}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {Autologous bone still represents today's gold standard for the treatment of critical size bone defects and fracture non-unions despite associated disadvantages regarding limitations in availability, donor site morbidity, costs and efficacy. Bone tissue engineered constructs would present a promising alternative to currently available treatments. However, research on preclinical animal studies still fails to provide clinical applicable results able to allow the replacement of currently applied methods. It seems that the idea of bone tissue engineering, which has now been integral part of academic studies for over 30 years, got somehow stuck at an intermediate level, in between intense preclinical research and striven stages of initial clinical trial phases. A clear discrepancy exists between the number of studies with preclinical animal models for bone tissue engineering and the number of clinically approved bone tissue engineered constructs available to patients. The aim of this thesis was hence to evaluate preclinical animal models for bone tissue engineering as well as the perception of scientists and clinicians towards these models. Moreover, the general role of bone tissue engineering and its clinical need assessed by scientists and surgeons was investigated. A survey was conducted questioning both scientific and clinical opinions on currently available study designs and researchers' satisfaction with preclinical animal models. Additionally, a literature research was conducted, resulting in 167 papers from the last 10 years that report current designs of preclinical orthotopic animal studies in bone tissue engineering. Thereby, the focus lied on the description of the models regarding animal species, strain, age, gender and defect design. The outcome of the literature search was evaluated and compared to the outcome obtained from the survey. The survey data revealed that both scientists and surgeons generally remain positive about the future role of bone tissue engineering and its step to clinical translation, at least in the distant future, where it then might replace the current gold standard, autologous bone. Moreover, most of the participants considered preclinical animal models as relevant and well developed but the results as not yet realizable in the clinics. Surgeons thereby demonstrated a slightly more optimistic perception of currently conducted research with animal models compared to scientists. However, a rather inconsistent description of present preclinical study designs could be discerned when evaluating the reported study designs in the survey and the papers of the literature search. Indeed, defining an appropriate animal species, strain, age, gender, observation time, observation method and surgical design often depends on different indications and research questions and represents a highly challenging task for the establishment of a preclinical animal model. The existing lack of valid guidelines for preclinical testing of bone tissue engineering leads hence to a lack of well standardized preclinical animal models. Moreover, still existing knowledge gaps regarding aspects that affect the process of fracture healing, such as vascularization or immunological aspects, were found to hinder clinical translation of bone tissue engineered constructs. Using literature review and survey, this thesis points out critical issues that need to be addressed to allow clinical translation of bone tissue engineered constructs. It can be concluded that currently existing study designs with preclinical animal models cannot live up to the claim of providing suitable results for clinical implementation. The here presented comprehensive summary of currently used preclinical animal models for bone tissue engineering reveals a missing consensus on the usage of models such as an apparent lack of reporting and standardization regarding the study designs described in both papers from the literature review and the survey. It thereby indicates a crucial need to improve preclinical animal models in order to allow clinical translation. Despite the fact that participants of the survey generally revealed a positive perception towards the use of bone tissue engineered constructs and affirmed the clinical need for such novel designs, the missing standardization constitutes a main weak point for the provision of reliable study outcome and the translational success of the models. The optimization of reproducibility and reliability, as well as the further understanding of ongoing mechanisms in bone healing in order to develop effective tissue engineered constructs, need to form the basis of all study designs. The study outcomes might then fulfill the requirements of maybe today's and hopefully tomorrow's aging population.}, language = {en} } @article{DotterweichSchlegelmilchKelleretal.2016, author = {Dotterweich, Julia and Schlegelmilch, Katrin and Keller, Alexander and Geyer, Beate and Schneider, Doris and Zeck, Sabine and Tower, Robert J. J. and Ebert, Regina and Jakob, Franz and Sch{\"u}tze, Norbert}, title = {Contact of myeloma cells induces a characteristic transcriptome signature in skeletal precursor cells-implications for myeloma bone disease}, series = {Bone}, volume = {93}, journal = {Bone}, doi = {10.1016/j.bone.2016.08.006}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-186688}, pages = {155-166}, year = {2016}, abstract = {Physical interaction of skeletal precursors with multiple myeloma cells has been shown to suppress their osteogenic potential while favoring their tumor-promoting features. Although several transcriptome analyses of myeloma patient-derived mesenchymal stem cells have displayed differences compared to their healthy counterparts, these analyses insufficiently reflect the signatures mediated by tumor cell contact, vary due to different methodologies, and lack results in lineage-committed precursors. To determine tumor cell contact-mediated changes on skeletal precursors, we performed transcriptome analyses of mesenchymal stem cells and osteogenic precursor cells cultured in contact with the myeloma cell line INA-6. Comparative analyses confirmed dysregulation of genes which code for known disease-relevant factors and additionally revealed upregulation of genes that are associated with plasma cell homing, adhesion, osteoclastogenesis, and angiogenesis. Osteoclast-derived coupling factors, a dysregulated adipogenic potential, and an imbalance in favor of anti-anabolic factors may play a role in the hampered osteoblast differentiation potential of mesenchymal stem cells. Angiopoietin-Like 4 (ANGPTL4) was selected from a list of differentially expressed genes as a myeloma cell contact-dependent target in skeletal precursor cells which warranted further functional analyses. Adhesion assays with full-length ANGPTL4-coated plates revealed a potential role of this protein in INA6 cell attachment. This study expands knowledge of the myeloma cell contact-induced signature in the stromal compartment of myelomatous bones and thus offers potential targets that may allow detection and treatment of myeloma bone disease at an early stage.}, language = {en} } @article{ArnholdtKamawalHolzapfeletal.2018, author = {Arnholdt, J{\"o}rg and Kamawal, Yama and Holzapfel, Boris Michael and Ripp, Axel and Rudert, Maximilian and Steinert, Andre Friedrich}, title = {Evaluation of implant fit and frontal plane alignment after bi-compartmental knee arthroplasty using patient-specific instruments and implants}, series = {Archives of Medical Science}, volume = {14}, journal = {Archives of Medical Science}, number = {6}, doi = {10.5114/aoms.2018.79007}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-159668}, pages = {1424-1431}, year = {2018}, abstract = {Introduction The goals of successful bi-compartmental knee arthroplasty are to achieve correct fit and positioning of the implant, while appropriately correcting the mechanical alignment of the leg after surgery. As these requirements are not always reliably fulfilled using off-the-shelf implant systems, newer approaches for bi-compartmental resurfacing have been explored. Material and methods In this article we report the radiographic results of 30 patients with anteromedial osteoarthritis (OA) who were treated with a novel patient-specific fixed-bearing bi-compartmental knee resurfacing system using custom-made implants and instruments. Utilizing standardized pre- and postoperative radiographic analyses (based on anterior-posterior and lateral, anterior-posterior weight-bearing full-length radiographs, patella skyline views and preoperative computed tomography (CT) scanning) implant fit and positioning as well as correction of the mechanical axis (hip-knee-ankle angle, HKA) were determined. Results On average, HKA was corrected from 173.4 ±3.47° preoperatively to 179.4 ±2.85° postoperatively. The coronal femoro-tibial angle was corrected on average 5.61°. The preoperative tibial slope measured on lateral views was 6.38 ±2.4°, while the average slope in the CT-based planning protocol (iView) was 6.14 ±2.40°. Postoperative lateral tibial slope was determined to be 5.77 ±1.97°. The thickness of the posterior femoral cuts was measured intraoperatively and, in all cases, corresponded well to the targeted thickness of the cuts provided by the iView. The joint line was preserved in all cases and the average Insall-Salvati index was 1.078 ±0.11 pre- and 1.072 ±0.11 postoperatively. The fit of the implant components measured by over- or underhang was excellent throughout (< 1.01 mm). Conclusions Custom-made bicompartmental knee arthroplasty can ensure optimized fitting and positioning of the implant with restoration of the leg axis. These implants could be considered as an alternative primary solution for knee surgeons treating bi-compartmental disease.}, language = {en} } @article{WittmannSiebervonStengeletal.2016, author = {Wittmann, Katharina and Sieber, Cornel and von Stengel, Simon and Kohl, Matthias and Freiberger, Ellen and Jakob, Franz and Lell, Michael and Engelke, Klaus and Kemmler, Wolfgang}, title = {Impact of whole body electromyostimulation on cardiometabolic risk factors in older women with sarcopenic obesity: the randomized controlled FORMOsA-sarcopenic obesity study}, series = {Clinical Interventions in Aging}, volume = {11}, journal = {Clinical Interventions in Aging}, doi = {10.2147/CIA.S116430}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-164930}, pages = {1697—1706}, year = {2016}, abstract = {Background: Sarcopenic obesity (SO) is characterized by a combination of low muscle and high fat mass with an additive negative effect of both conditions on cardiometabolic risk. The aim of the study was to determine the effect of whole-body electromyostimulation (WB-EMS) on the metabolic syndrome (MetS) in community-dwelling women aged ≥70 years with SO. Methods: The study was conducted in an ambulatory university setting. Seventy-five community-dwelling women aged ≥70 years with SO living in Northern Bavaria, Germany, were randomly allocated to either 6 months of WB-EMS application with (WB-EMS\&P) or without (WB-EMS) dietary supplementation (150 kcal/day, 56\% protein) or a non-training control group (CG). WB-EMS included one session of 20 min (85 Hz, 350 µs, 4 s of strain-4 s of rest) per week with moderate-to-high intensity. The primary study endpoint was the MetS Z-score with the components waist circumference (WC), mean arterial pressure (MAP), triglycerides, fasting plasma glucose, and high-density lipoprotein cholesterol (HDL-C); secondary study endpoints were changes in these determining variables. Results: MetS Z-score decreased in both groups; however, changes compared with the CG were significant (P=0.001) in the WB-EMS\&P group only. On analyzing the components of the MetS, significant positive effects for both WB-EMS groups (P≤0.038) were identified for MAP, while the WB-EMS group significantly differed for WC (P=0.036), and the WB-EMS\&P group significantly differed for HDL-C (P=0.006) from the CG. No significant differences were observed between the WB-EMS groups. Conclusion: The study clearly confirms the favorable effect of WB-EMS application on the MetS in community-dwelling women aged ≥70 years with SO. However, protein-enriched supplements did not increase effects of WB-EMS alone. In summary, we considered this novel technology an effective and safe method to prevent cardiometabolic risk factors and diseases in older women unable or unwilling to exercise conventionally.}, language = {en} } @article{DotterweichTowerBrandletal.2016, author = {Dotterweich, Julia and Tower, Robert J. and Brandl, Andreas and M{\"u}ller, Marc and Hofbauer, Lorenz C. and Beilhack, Andreas and Ebert, Regina and Gl{\"u}er, Claus C. and Tiwari, Sanjay and Sch{\"u}tze, Norbert and Jakob, Franz}, title = {The KISS1 Receptor as an In Vivo Microenvironment Imaging Biomarker of Multiple Myeloma Bone Disease}, series = {PLoS One}, volume = {11}, journal = {PLoS One}, number = {5}, doi = {10.1371/journal.pone.0155087}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146960}, pages = {e0155087}, year = {2016}, abstract = {Multiple myeloma is one of the most common hematological diseases and is characterized by an aberrant proliferation of plasma cells within the bone marrow. As a result of crosstalk between cancer cells and the bone microenvironment, bone homeostasis is disrupted leading to osteolytic lesions and poor prognosis. Current diagnostic strategies for myeloma typically rely on detection of excess monoclonal immunoglobulins or light chains in the urine or serum. However, these strategies fail to localize the sites of malignancies. In this study we sought to identify novel biomarkers of myeloma bone disease which could target the malignant cells and/or the surrounding cells of the tumor microenvironment. From these studies, the KISS1 receptor (KISS1R), a G-protein-coupled receptor known to play a role in the regulation of endocrine functions, was identified as a target gene that was upregulated on mesenchymal stem cells (MSCs) and osteoprogenitor cells (OPCs) when co-cultured with myeloma cells. To determine the potential of this receptor as a biomarker, in vitro and in vivo studies were performed with the KISS1R ligand, kisspeptin, conjugated with a fluorescent dye. In vitro microscopy showed binding of fluorescently-labeled kisspeptin to both myeloma cells as well as MSCs under direct co-culture conditions. Next, conjugated kisspeptin was injected into immune-competent mice containing myeloma bone lesions. Tumor-burdened limbs showed increased peak fluorescence compared to contralateral controls. These data suggest the utility of the KISS1R as a novel biomarker for multiple myeloma, capable of targeting both tumor cells and host cells of the tumor microenvironment.}, language = {en} } @article{KamawalSteinertHolzapfeletal.2016, author = {Kamawal, Yama and Steinert, Andre F and Holzapfel, Boris M and Rudert, Maximilian and Barthel, Thomas}, title = {Case report - calcification of the medial collateral ligament of the knee with simultaneous calcifying tendinitis of the rotator cuff}, series = {BMC Muscoskeletal Disorders}, volume = {17}, journal = {BMC Muscoskeletal Disorders}, number = {283}, doi = {10.1186/s12891-016-1147-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-147669}, year = {2016}, abstract = {Calcification of the medial collateral ligament (MCL) of the knee is a very rare disease. We report on a case of a patient with a calcifying lesion within the MCL and simultaneous calcifying tendinitis of the rotator cuff in both shoulders. Case presentation: Calcification of the MCL was diagnosed both via x-ray and magnetic resonance imaging (MRI) and was successfully treated surgically. Calcifying tendinitis of the rotator cuff was successfully treated applying conservative methods. Conclusion: This is the first case report of a patient suffering from both a calcifying lesion within the medial collateral ligament and calcifying tendinitis of the rotator cuff in both shoulders. Clinical symptoms, radio-morphological characteristics and macroscopic features were very similar and therefore it can be postulated that the underlying pathophysiology is the same in both diseases. Our experience suggests that magnetic resonance imaging and x-ray are invaluable tools for the diagnosis of this inflammatory calcifying disease of the ligament, and that surgical repair provides a good outcome if conservative treatment fails. It seems that calcification of the MCL is more likely to require surgery than calcifying tendinitis of the rotator cuff. However, the exact reason for this remains unclear to date.}, language = {en} } @article{WehrleLiedertHeilmannetal.2015, author = {Wehrle, Esther and Liedert, Astrid and Heilmann, Aline and Wehner, Tim and Bindl, Ronny and Fischer, Lena and Haffner-Luntzer, Melanie and Jakob, Franz and Schinke, Thorsten and Amling, Michael and Ignatius, Anita}, title = {The impact of low-magnitude high-frequency vibration on fracture healing is profoundly influenced by the oestrogen status in mice}, series = {Disease Models \& Mechanisms}, volume = {8}, journal = {Disease Models \& Mechanisms}, doi = {10.1242/dmm.018622}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-144700}, pages = {93-104}, year = {2015}, abstract = {Fracture healing is impaired in aged and osteoporotic individuals. Because adequate mechanical stimuli are able to increase bone formation, one therapeutical approach to treat poorly healing fractures could be the application of whole-body vibration, including low-magnitude high-frequency vibration (LMHFV). We investigated the effects of LMHFV on fracture healing in aged osteoporotic mice. Female C57BL/6NCrl mice (n=96) were either ovariectomised (OVX) or sham operated (non-OVX) at age 41 weeks. When aged to 49 weeks, all mice received a femur osteotomy that was stabilised using an external fixator. The mice received whole-body vibrations (20 minutes/day) with 0.3 g peak-to-peak acceleration and a frequency of 45 Hz. After 10 and 21 days, the osteotomised femurs and intact bones (contra-lateral femurs, lumbar spine) were evaluated using bending-testing, micro-computed tomography (mu CT), histology and gene expression analyses. LMHFV disturbed fracture healing in aged non-OVX mice, with significantly reduced flexural rigidity (-81\%) and bone formation (-80\%) in the callus. Gene expression analyses demonstrated increased oestrogen receptor β (ERβ, encoded by Esr2) and Sost expression in the callus of the vibrated animals, but decreased β-catenin, suggesting that ERβ might mediate these negative effects through inhibition of osteoanabolic Wnt/β-catenin signalling. In contrast, in OVX mice, LMHFV significantly improved callus properties, with increased flexural rigidity (+ 1398\%) and bone formation (+637\%), which could be abolished by subcutaneous oestrogen application (0.025 mg oestrogen administered in a 90-day-release pellet). On a molecular level, we found an upregulation of ER alpha in the callus of the vibrated OVX mice, whereas ERβ was unaffected, indicating that ERa might mediate the osteoanabolic response. Our results indicate a major role for oestrogen in the mechanostimulation of fracture healing and imply that LMHFV might only be safe and effective in confined target populations.}, language = {en} } @article{RudertHorasHobergetal.2016, author = {Rudert, Maximilian and Horas, Konstantin and Hoberg, Maik and Steinert, Andre and Holzapfel, Dominik Emanuel and H{\"u}bner, Stefan and Holzapfel, Boris Michael}, title = {The Wuerzburg procedure: the tensor fasciae latae perforator is a reliable anatomical landmark to clearly identify the Hueter interval when using the minimally-invasive direct anterior approach to the hip joint}, series = {BMC Musculoskeletal Disorders}, volume = {17}, journal = {BMC Musculoskeletal Disorders}, number = {57}, doi = {10.1186/s12891-016-0908-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146031}, year = {2016}, abstract = {Background The key for successful delivery in minimally-invasive hip replacement lies in the exact knowledge about the surgical anatomy. The minimally-invasive direct anterior approach to the hip joint makes it necessary to clearly identify the tensor fasciae latae muscle in order to enter the Hueter interval without damaging the lateral femoral cutaneous nerve. However, due to the inherently restricted overview in minimally-invasive surgery, this can be difficult even for experienced surgeons. Methods and Surgical Technique In this technical note, we demonstrate for the first time how to use the tensor fasciae latae perforator as anatomical landmark to reliably identify the tensor fasciae latae muscle in orthopaedic surgery. Such perforators are used for flaps in plastic surgery as they are constant and can be found at the lateral third of the tensor fasciae latae muscle in a direct line from the anterior superior iliac spine. Conclusion As demonstrated in this article, a simple knowledge transfer between surgical disciplines can minimize the complication rate associated with minimally-invasive hip replacement.}, language = {en} } @article{KonradsHobergRudert2015, author = {Konrads, C. and Hoberg, M. and Rudert, M.}, title = {New Mechanism of Hip Endoprosthesis Damage Caused by High-frequency Electrocautery}, series = {Journal of Medical Implants \& Surgery}, volume = {1}, journal = {Journal of Medical Implants \& Surgery}, number = {1}, doi = {10.4172/jmis.1000102}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146528}, pages = {103}, year = {2015}, abstract = {No abstract available.}, language = {en} } @article{KonradsBarthel2015, author = {Konrads, Christian and Barthel, Thomas}, title = {Children and Adolescents with Knee Pain Need Diagnostics for Osteochondritis Dissecans}, series = {Journal of Pain Management \& Medicine}, volume = {2}, journal = {Journal of Pain Management \& Medicine}, number = {1}, doi = {10.4172/jpmme.1000107}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146531}, pages = {107}, year = {2015}, abstract = {No abstract available.}, language = {en} } @article{ThibaudeauTaubenbergerTheodoropoulosetal.2015, author = {Thibaudeau, Laure and Taubenberger, Anna V. and Theodoropoulos, Christina and Holzapfel, Boris M. and Ramuz, Olivier and Straub, Melanie and Hutmacher, Dietmar W.}, title = {New mechanistic insights of integrin β1 in breast cancer bone colonization}, series = {Oncotarget}, volume = {6}, journal = {Oncotarget}, number = {1}, doi = {10.18632/oncotarget.2788}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-175432}, pages = {332-344}, year = {2015}, abstract = {Bone metastasis is a frequent and life-threatening complication of breast cancer. The molecular mechanisms supporting the establishment of breast cancer cells in the skeleton are still not fully understood, which may be attributed to the lack of suitable models that interrogate interactions between human breast cancer cells and the bone microenvironment. Although it is well-known that integrins mediate adhesion of malignant cells to bone extracellular matrix, their role during bone colonization remains unclear. Here, the role of β1 integrins in bone colonization was investigated using tissue-engineered humanized in vitro and in vivo bone models. In vitro, bone-metastatic breast cancer cells with suppressed integrin β1 expression showed reduced attachment, spreading, and migration within human bone matrix compared to control cells. Cell proliferation in vitro was not affected by β1 integrin knockdown, yet tumor growth in vivo within humanized bone microenvironments was significantly inhibited upon β1 integrin suppression, as revealed by quantitative in/ex vivo fluorescence imaging and histological analysis. Tumor cells invaded bone marrow spaces in the humanized bone and formed osteolytic lesions; osteoclastic bone resorption was, however, not reduced by β1 integrin knockdown. Taken together, we demonstrate that β1 integrins have a pivotal role in bone colonization using unique tissue-engineered humanized bone models.}, language = {en} } @article{HolzapfelRechlLehneretal.2011, author = {Holzapfel, Boris Michael and Rechl, Hans and Lehner, Stefan and Pilge, Hakan and Gollwitzer, Hans and Steinhauser, Erwin}, title = {Alloplastic Reconstruction of the Extensor Mechanism after Resection of Tibial Sarcoma [Research Article]}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-69072}, year = {2011}, abstract = {Reconstruction of the extensor mechanism is essential for good extremity function after endoprosthetic knee replacement following tumor resection. Only a few biological methods have been able to reliably restore a functional extensor mechanism, but they are often associated with significant complication rates. Reattachment of the patellar tendon to the prosthesis using an alloplastic patellar ligament (Trevira cord) can be an appropriate alternative. In vivo and in vitro studies have already shown that complete fibrous ingrowth in polyethylene chords can be seen after a period of six months. However, until now, no biomechanical study has shown the efficacy of an alloplastic cord and its fixation device in providing sufficient stability and endurance in daily life-activity until newly formed scar tissue can take over this function. In a special test bench developed for this study, different loading regimes were applied to simulate loads during everyday life. Failure loads and failuremodes were evaluated. The properties of the cord were compared before and after physiological conditioning. It was shown that rubbing was the mode of failure under dynamic loading. Tensile forces up to 2558N did not result in material failure. Thus, using an artificial cord together with this fixation device, temporary sufficient stable fixation can be expected.}, subject = {Medizin}, language = {en} } @article{SeefriedMuellerDeubertSchwarzetal.2010, author = {Seefried, Lothar and Mueller-Deubert, Sigrid and Schwarz, Thomas and Lind, Thomas and Mentrup, Birgit and Kober, Melanie and Docheva, Denitsa and Liedert, Astrid and Kassem, Moustapha and Ignatius, Anita and Schieker, Matthias and Claes, Lutz and Wilke, Winfried and Jakob, Franz and Ebert, Regina}, title = {A small scale cell culture system to analyze mechanobiology using reporter gene constructs and polyurethane dishes}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68099}, year = {2010}, abstract = {Mechanical forces are translated into biochemical signals and contribute to cell differentiation and phenotype maintenance. Mesenchymal stem cells and their tissuespecific offspring, as osteoblasts and chondrocytes, cells of cardiovascular tissues and lung cells are sensitive to mechanical loading but molecules and mechanisms involved have to be unraveled. It is well established that cellular mechanotransduction is mediated e.g. by activation of the transcription factor SP1 and by kinase signaling cascades resulting in the activation of the AP1 complex. To investigate cellular mechanisms involved in mechanotransduction and to analyze substances, which modulate cellular mechanosensitivity reporter gene constructs, which can be transfected into cells of interest might be helpful. Suitable small-scale bioreactor systems and mechanosensitive reporter gene constructs are lacking. To analyze the molecular mechanisms of mechanotransduction and its crosstalk with biochemically induced signal transduction, AP1 and SP1 luciferase reporter gene constructs were cloned and transfected into various cell lines and primary cells. A newly developed bioreactor and small-scale 24-well polyurethane dishes were used to apply cyclic stretching to the transfected cells. 1 Hz cyclic stretching for 30 min in this system resulted in a significant stimulation of AP1 and SP1 mediated luciferase activity compared to unstimulated cells. In summary we describe a small-scale cell culture/bioreactor system capable of analyzing subcellular crosstalk mechanisms in mechanotransduction, mechanosensitivity of primary cells and of screening the activity of putative mechanosensitizers as new targets, e.g. for the treatment of bone loss caused by both disuse and signal transduction related alterations of mechanotransduction.}, subject = {Bioreaktor}, language = {en} } @phdthesis{Schlegelmilch2012, author = {Schlegelmilch, Katrin}, title = {Molecular function of WISP1/CCN4 in the musculoskeletal system with special reference to apoptosis and cell survival}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-73430}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2012}, abstract = {Human adult cartilage is an aneural and avascular type of connective tissue, which consequently reflects reduced growth and repair rates. The main cell type of cartilage are chondrocytes, previously derived from human mesenchymal stem cells (hMSCs). They are responsible for the production and maintainance of the cartilaginous extracellular matrix (ECM), which consists mainly of collagen and proteoglycans. Signal transmission to or from chondrocytes, generally occurs via interaction with signalling factors connected to the cartilaginous ECM. In this context, proteins of the CCN family were identified as important matricellular and multifunctional regulators with high significance during skeletal development and fracture repair. In this thesis, main focus lies on WISP1/CCN4, which is known as a general survival factor in a variety of cell types and seems to be crucial during lineage progression of hMSCs into chondrocytes. We intend to counter the lack of knowledge about the general importance of WISP1-signalling within the musculoskeletal system and especially regarding cell death and survival by a variety of molecular and cell biology methods. First, we established a successful down-regulation of endogenous WISP1 transcripts within different cell types of the human musculoskeletal system through gene-silencing. Interestingly, WISP1 seems to be crucial to the survival of all examined cell lines and primary hMSCs, since a loss of WISP1 resulted in cell death. Bioinformatical analyses of subsequent performed microarrays (WISP1 down-regulated vs. control samples) confirmed this observation in primary hMSCs and the chondrocyte cell line Tc28a2. Distinct clusters of regulated genes, closely related to apoptosis induction, could be identified. In this context, TRAIL induced apoptosis as well as p53 mediated cell death seem to play a crucial role during the absence of WISP1 in hMSCs. By contrast, microarray analysis of WISP1 down-regulated chondrocytes indicated rather apoptosis induction via MAPK-signalling. Despite apoptosis relevant gene regulations, microarray analyses also identified clusters of differentially expressed genes of other important cellular activities, e.g. a huge cluster of interferon-inducible genes in hMSCs or gene regulations affecting cartilage homeostasis in chondrocytes. Results of this thesis emphasize the importance of regulatory mechanisms that influence cell survival of primary hMSCs and chondrocytes in the enforced absence of WISP1. Moreover, findings intensified the assumed importance for WISP1-signalling in cartilage homeostasis. Thus, this thesis generated an essential fundament for further examinations to investigate the role of WISP1-signalling in cartilage homeostasis and cell death.}, subject = {Knorpelzelle}, language = {en} } @phdthesis{HaddadWeber2010, author = {Haddad-Weber, Meike}, title = {Development of stem cell-based ACL- and tendon reconstruction}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-66796}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2010}, abstract = {Ruptures of the anterior cruciate ligament (ACL) and defects of the rotator cuff represent the most common ligament and tendon injuries in knee and shoulder. Both injuries represent significant implications for the patients. After an injury, the ACL and the rotator cuff both exhibit poor intrinsic healing capacities. In order to prevent further defects such as arthritis of the knee and fatty infiltration of the rotator cuff, surgical interaction is essential. In both cases, the currently used surgical techniques are far from optimal because even after the therapy many patients report problems ranging from pain and reduced mobility to complete dysfunction of the involved joint and muscles. Tissue engineering may be a possible solution. It is a promising field of regenerative medicine and might be an advantageous alternative for the treatment of musculoskeletal injuries and diseases in the near future. In this thesis, different tissue engineering based approaches were investigated. For the reconstruction of damaged or diseased ligaments and tendons, the use of MSCs and gene therapy with growth factors is especially suitable and possesses a great therapeutic potential. Therefore, the first method studied and tested in this thesis was the development of a biomaterial based construct for the repair of a ruptured ACL. The second approach represents a cell based strategy for the treatment of the fatty infiltration in the rotator cuff. The third approach was a combined cell, biomaterial, and growth factor based strategy for ACL ruptures. Biomaterial based ACL construct The implant is currently tested in a preclinical in vivo study in mini pigs. This proof-of-principle study is performed to validate the functional capability of the collagen fiber based implant under load in vivo and its population with fibroblasts which produce a ligamentogenic matrix. Cell based treatment of the fatty infiltration in the rotator cuff Regarding the treatment of the fatty infiltration of the rotator cuff in a rabbit model, the in vivo results are also promising. The group treated with autologous MSCs (+MSC group) showed a lower fat content than the untreated group (-MSC group) 6 weeks after the treatment. Furthermore, the SSP muscle of the MSC-treated animals revealed macroscopically and microscopically only few differences compared to the healthy control group. The exact underlying mechanisms leading to the positive results of the treatment are not yet fully understood and have therefore to be further investigated in the future. Cell, biomaterial, and growth factor based treatment of ACL ruptures Studies described in current literature show that collagen hydrogel scaffolds are not ideal for a complete ligament or tendon reconstruction, because of their insufficient mechanical stability. Introduced as an alternative and superior therapy, the combined strategy used in this thesis proves that the cultivation of BMP-12, -13, and IGF-1 transduced MSCs and ACL fibroblasts in a collagen hydrogel is successful. The results of the performed in vitro study reveal that the cells exhibit a fibroblastic appearance and produce a ligamentogenic matrix after 3 weeks. Furthermore, the adenoviral transduction of MSCs and ACL fibroblasts showed no negative effects on proliferation or viability of the cells nor was apoptosis caused. Therefore, the application of these cells represents a possible future therapy for a partial ligament and tendon rupture where the mechanical stability of the remaining ligament or tendon is sufficient and the healing can be improved substantially by this therapy. In general, prospective randomized clinical trials still have to prove the postulated positive effect of MSCs for the treatment of various musculoskeletal diseases, but the results obtained here are already very promising. Ideally, the treatment with MSCs is superior compared to the standard surgical procedures. Because of current safety issues the use of genetically modified cells cannot be expected to be applied clinically in the near future. In summary, the different tissue engineering approaches for novel therapies for musculoskeletal injuries and diseases invested in this thesis showed very promising results and will be further developed and tested in preclinical and clinical trials.}, subject = {Kreuzband}, language = {en} } @article{LjunggrenBarrettStoykovetal.2013, author = {Ljunggren, Osten and Barrett, Annabel and Stoykov, Ivaylo and Langdahl, Bente L. and Lems, Willem F. and Walsh, J. Bernard and Fahrleitner-Pammer, Astrid and Rajzbaum, Gerald and Jakob, Franz and Karras, Dimitrios and Marin, Fernando}, title = {Effective osteoporosis treatment with teriparatide is associated with enhanced quality of life in postmenopausal women with osteoporosis: the European Forsteo Observational Study}, series = {BMC Musculoskeletal Disorders}, volume = {14}, journal = {BMC Musculoskeletal Disorders}, number = {251}, issn = {1471-2474}, doi = {10.1186/1471-2474-14-251}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-122057}, year = {2013}, abstract = {Background: To describe changes in health-related quality of life (HRQoL) of postmenopausal women with osteoporosis treated with teriparatide for up to 18 months and followed-up for a further 18 months, and to assess the influence of recent prior and incident fractures. Methods: The European Forsteo Observational Study (EFOS) is an observational, prospective, multinational study measuring HRQoL using the EQ-5D. The primary objective was to assess changes in HRQoL during 36 months in the whole study population. A secondary post-hoc analysis examined fracture impact on HRQoL in four subgroups classified based on recent prior fracture 12 months before baseline and incident clinical fractures during the study. Changes from baseline were analysed using a repeated measures model. Results: Of the 1581 patients, 48.4\% had a recent prior fracture and 15.6\% of these patients had an incident fracture during follow-up. 10.9\% of the 816 patients with no recent prior fracture had an incident fracture. Baseline mean EQ-VAS scores were similar across the subgroups. In the total study cohort (n = 1581), HRQoL (EQ-VAS and EQ-5D index scores) improved significantly from baseline to 18 months and this improvement was maintained over the 18-month post-teriparatide period. Improvements were seen across all five EQ-5D domains during teriparatide treatment that were maintained after teriparatide was discontinued. Subjects with incident clinical fractures had significantly less improvement in EQ-VAS than those without incident fractures. Recent prior fracture did not influence the change in EQ-VAS during treatment. Conclusions: EFOS is the first longitudinal study in women with severe postmenopausal osteoporosis in the real world setting to show a substantial improvement in HRQoL during teriparatide treatment that was sustained during subsequent treatment with other medications. The increase in HRQoL was lower in the subgroups with incident fracture but was not influenced by recent prior fracture. The results should be interpreted in the context of the design of an observational study.}, language = {en} } @article{WimmerRandauDemletal.2013, author = {Wimmer, Matthias D. and Randau, Thomas M. and Deml, Moritz C. and Ascherl, Rudolf and Forst, Raimund and Gravius, Nadine and Wirtz, Dieter and Gravius, Sascha}, title = {Impaction grafting in the femur in cementless modular revision total hip arthroplasty: a descriptive outcome analysis of 243 cases with the MRP-TITAN revision implant}, series = {BMC Musculoskeletal Disorders}, volume = {14}, journal = {BMC Musculoskeletal Disorders}, number = {19}, issn = {1471-2474}, doi = {10.1186/1471-2474-14-19}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-122061}, year = {2013}, abstract = {Background: We present a descriptive and retrospective analysis of revision total hip arthroplasties (THA) using the MRP-TITAN stem (Peter Brehm, Weisendorf, GER) with distal diaphyseal fixation and metaphyseal defect augmentation. Our hypothesis was that the metaphyseal defect augmentation (Impaction Bone Grafting) improves the stem survival. Methods: We retrospectively analyzed the aggregated and anonymized data of 243 femoral stem revisions. 68 patients with 70 implants (28.8\%) received an allograft augmentation for metaphyseal defects; 165 patients with 173 implants (71.2\%) did not, and served as controls. The mean follow-up was 4.4 +/- 1.8 years (range, 2.1-9.6 years). There were no significant differences (p > 0.05) between the study and control group regarding age, body mass index (BMI), femoral defects (types I-III as described by Paprosky), and preoperative Harris Hip Score (HHS). Postoperative clinical function was evaluated using the HHS. Postoperative radiologic examination evaluated implant stability, axial implant migration, signs of implant loosening, periprosthetic radiolucencies, as well as bone regeneration and resorption. Results: There were comparable rates of intraoperative and postoperative complications in the study and control groups (p > 0.05). Clinical function, expressed as the increase in the postoperative HHS over the preoperative score, showed significantly greater improvement in the group with Impaction Bone Grafting (35.6 +/- 14.3 vs. 30.8 +/- 15.8; p <= 0.05). The study group showed better outcome especially for larger defects (types II C and III as described by Paprosky) and stem diameters >= 17 mm. The two groups did not show significant differences in the rate of aseptic loosening (1.4\% vs. 2.9\%) and the rate of revisions (8.6\% vs. 11\%). The Kaplan-Meier survival for the MRP-TITAN stem in both groups together was 93.8\% after 8.8 years. [Study group 95.7\% after 8.54 years; control group 93.1\% after 8.7 years]. Radiologic evaluation showed no significant change in axial implant migration (4.3\% vs. 9.3\%; p = 0.19) but a significant reduction in proximal stress shielding (5.7\% vs. 17.9\%; p < 0.05) in the study group. Periprosthetic radiolucencies were detected in 5.7\% of the study group and in 9.8\% of the control group (p = 0.30). Radiolucencies in the proximal zones 1 and 7 according to Gruen occurred significantly more often in the control group without allograft augmentation (p = 0.05). Conclusion: We present the largest analysis of the impaction grafting technique in combination with cementless distal diaphyseal stem fixation published so far. Our data provides initial evidence of improved bone regeneration after graft augmentation of metaphyseal bone defects. The data suggests that proximal metaphyseal graft augmentation is beneficial for large metaphyseal bone defects (Paprosky types IIC and III) and stem diameters of 17 mm and above. Due to the limitations of a retrospective and descriptive study the level of evidence remains low and prospective trials should be conducted.}, language = {en} } @article{BoelchBarthelGoebeletal.2015, author = {Boelch, Sebastian Philipp and Barthel, Thomas and Goebel, Sascha and Rudert, Maximilian and Plumhoff, Piet}, title = {Calcinosis universalis - a rare case with classical presentation}, series = {Case Reports in Orthopedics}, volume = {2015}, journal = {Case Reports in Orthopedics}, doi = {10.1155/2015/505420}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126300}, pages = {505420}, year = {2015}, abstract = {Juvenile Dermatomyositis (JDM) is a rare autoimmune disease in children and adolescents. In these patients calcinosis might be the most characteristic symptom. However there are only few reported cases of intramuscular calcinosis in Dermatomyositis. We report a case of calcinosis universalis (CU) of the elbow in JDM successfully treated with broaching. The patient, a 24-year-old woman, suffered from a long history of JDM. On examination she presented with a fistula lateral to the olecranon and pain of the right elbow joint. Plain X-rays displayed a diffuse pattern of multiple periarticular, subcutaneous, and intramuscular calcifications. The patient underwent surgery for histological and microbiological sampling as well as broaching. Intraoperatively sinus formation and subfascial hard calcium deposition were found. Due to the risk of collateral tissue damage, incomplete broaching was performed. A local infection with Staphylococcus was diagnosed and treated with antibiotics. On six-week and 30-month follow-up the patient was free of pain and had very good function. Calcifications on standard radiographs had almost resolved entirely. This case report gives a summary on calcinosis in Dermatomyositis and adds a new case of recalcitrant CU to the literature. Broaching surgery proved to be a reliable treatment option in symptomatic calcinosis.}, language = {en} } @article{SteinertKunzPrageretal.2015, author = {Steinert, Andre F. and Kunz, Manuela and Prager, Patrick and G{\"o}bel, Sascha and Klein-Hitpass, Ludger and Ebert, Regina and N{\"o}th, Ulrich and Jakob, Franz and Gohlke, Frank}, title = {Characterization of bursa subacromialis-derived mesenchymal stem cells}, series = {Stem Cell Research \& Therapy}, volume = {6}, journal = {Stem Cell Research \& Therapy}, number = {114}, doi = {10.1186/s13287-015-0104-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126446}, year = {2015}, abstract = {Introduction The bursa subacromialis (BS) provides the gliding mechanism of the shoulder and regenerates itself after surgical removal. Therefore, we explored the presence of mesenchymal stem cells (MSCs) within the human adult BS tissue and characterized the BS cells compared to MSCs from bone marrow (BMSCs) on a molecular level. Methods BS cells were isolated by collagenase digest from BS tissues derived from patients with degenerative rotator cuff tears, and BMSCs were recovered by adherent culture from bone-marrow of patients with osteoarthritis of the hip. BS cells and BMSCs were compared upon their potential to proliferate and differentiate along chondrogenic, osteogenic and adipogenic lineages under specific culture conditions. Expression profiles of markers associated with mesenchymal phenotypes were comparatively evaluated by flow cytometry, immunohistochemistry, and whole genome array analyses. Results BS cells and BMSCs appeared mainly fibroblastic and revealed almost similar surface antigen expression profiles, which was \(CD44^+, CD73^+, CD90^+, CD105^+, CD106^+\),\(STRO-1^+, CD14^-, CD31^-, CD34^- , CD45^-, CD144^-\). Array analyses revealed 1969 genes upregulated and 1184 genes downregulated in BS cells vs. BMSCs, indicating a high level of transcriptome similarity. After 3 weeks of differentiation culture, BS cells and BMSCs showed a similar strong chondrogenic, adipogenic and osteogenic potential, as shown by histological, immunohistochemical and RT-PCR analyses in contrast to the respective negative controls. Conclusions Our in vitro characterizations show that BS cells fulfill all characteristics of mesenchymal stem cells, and therefore merit further attention for the development of improved therapies for various shoulder pathologies.}, language = {en} } @phdthesis{Hondke2014, author = {Hondke, Sylvia}, title = {Elucidation of WISP3 function in human mesenchymal stem cells and chondrocytes}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-109641}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2014}, abstract = {WISP3 is a member of the CCN family which comprises six members found in the 1990's: Cysteine-rich,angiogenic inducer 61 (CYR61, CCN1), Connective tissue growth factor (CTGF, CCN2), Nephroblastoma overexpressed (NOV, CNN3) and the Wnt1 inducible signalling pathway protein 1-3 (WISP1-3, CCN4-6).They are involved in the adhesion, migration, mitogenesis, chemotaxis, proliferation, cell survival, angiogenesis, tumorigenesis, and wound healing by the interaction with different integrins and heparan sulfate proteoglycans. Until now the only member correlated to the musculoskeletal autosomal disease Progressive Pseudorheumatoid Dysplasia (PPD) is WISP3. PPD is characterised by normal embryonic development followed by cartilage degradation over time starting around the age of three to eight years. Animal studies in mice exhibited no differences between knock out or overexpression compared to wild type litter mates, thus were not able to reproduce the symptoms observed in PPD patients. Studies in vitro and in vivo revealed a role for WISP3 in antagonising BMP, IGF and Wnt signalling pathways. Since most of the knowledge of WISP3 was gained in epithelial cells, cancer cells or chondrocyte cell lines, we investigated the roll of WISP3 in primary human mesenchymal stem cells (hMSCs) as well as primary chondrocytes. WISP3 knock down was efficiently established with three short hairpin RNAs in both cell types, displaying a change of morphology followed by a reduction in cell number. Simultaneous treatment with recombinant WISP3 was not enough to rescue the observed phenotype nor increase the endogenous expression of WISP3. We concluded that WISP3 acts as an essential survival factor, where the loss resulted in the passing of cell cycle control points followed by apoptosis. Nevertheless, Annexin V-Cy3 staining and detection of active caspases by Western blot and immunofluorescence staining detected no clear evidence for apoptosis. Furthermore, the gene expression of the death receptors TRAILR1 and TRAILR2,important for the extrinsic activation of apoptosis, remained unchanged during WISP3 mRNA reduction. Autophagy as cause of cell death was also excluded, given that the autophagy marker LC3 A/B demonstrated to be uncleaved in WISP3-deficient hMSCs. To reveal correlated signalling pathways to WISP3 a whole genome expression analyses of WISP3-deficient hMSCs compared to a control (scramble) was performed. Microarray analyses exhibited differentially regulated genes involved in cell cycle control, adhesion, cytoskeleton and cell death. Cell death observed by WISP3 knock down in hMSCs and chondrocytes might be explained by the induction of necroptosis through the BMP/TAK1/RIPK1 signalling axis. Loss of WISP3 allows BMP to bind its receptor activating the Smad 2/3/4 complex which in turn can activate TAK1 as previously demonstrated in epithelial cells. TAK1 is able to block caspase-dependent apoptosis thereby triggering the assembly of the necrosome resulting in cell death by necroptosis. Together with its role in cell cycle control and extracellular matrix adhesion, as demonstrated in human mammary epithelial cells, the data supports the role of WISP3 as tumor suppressor and survival factor in cells of the musculoskeletal system as well as epithelial cells.}, subject = {Knorpelzelle}, language = {en} } @article{EbertJakobMeissnerWeigletal.2014, author = {Ebert, Regina and Jakob, Franz and Meissner-Weigl, Jutta and Zeck, Sabine and M{\"a}{\"a}tt{\"a}, Jorma and Auriola, Seppo and de Sousa, Sofia Coimbra and Mentrup, Birgit and Graser, Stephanie and Rachner, Tilman D. and Hofbauer, Lorenz C.}, title = {Probenecid as a sensitizer of bisphosphonate-mediated effects in breast cancer cells}, doi = {10.1186/1476-4598-13-265}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-111174}, year = {2014}, abstract = {Background: Anti-resorptive bisphosphonates (BP) are used for the treatment of osteoporosis and bone metastases. Clinical studies indicated a benefit in survival and tumor relapse in subpopulations of breast cancer patients receiving zoledronic acid, thus stimulating the debate about its anti-tumor activity. Amino-bisphosphonates in nM concentrations inhibit farnesyl pyrophosphate synthase leading to accumulation of isopentenyl pyrophosphate (IPP) and the ATP/ pyrophosphate adduct ApppI, which induces apoptosis in osteoclasts. For anti-tumor effects μM concentrations are needed and a sensitizer for bisphosphonate effects would be beneficial in clinical anti-tumor applications. We hypothesized that enhancing intracellular pyrophosphate accumulation via inhibition of probenecid-sensitive channels and transporters would sensitize tumor cells for bisphosphonates anti-tumor efficacy. Methods: MDA-MB-231, T47D and MCF-7 breast cancer cells were treated with BP (zoledronic acid, risedronate, ibandronate, alendronate) and the pyrophosphate channel inhibitors probenecid and novobiocin. We determined cell viability and caspase 3/7 activity (apoptosis), accumulation of IPP and ApppI, expression of ANKH, PANX1, ABCC1, SLC22A11, and the zoledronic acid target gene and tumor-suppressor KLF2. Results: Treatment of MDA-MB-231 with BP induced caspase 3/7 activity, with zoledronic acid being the most effective. In MCF-7 and T47D either BP markedly suppressed cell viability with only minor effects on apoptosis. Co-treatment with probenecid enhanced BP effects on cell viability, IPP/ApppI accumulation as measurable in MCF-7 and T47D cells, caspase 3/7 activity and target gene expression. Novobiocin co-treatment of MDA-MB-231 yielded identical results on viability and apoptosis compared to probenecid, rendering SLC22A family members as candidate modulators of BP effects, whereas no such evidence was found for ANKH, ABCC1 and PANX1. Conclusions: In summary, we demonstrate effects of various bisphosphonates on caspase 3/7 activity, cell viability and expression of tumor suppressor genes in breast cancer cells. Blocking probenecid- and novobiocin-sensitive channels and transporters enhances BP anti-tumor effects and renders SLC22A family members good candidates as BP modulators. Further studies will have to unravel if treatment with such BP-sensitizers translates into preclinical and clinical efficacy.}, language = {en} } @article{WehrleLiedertHeilmannetal.2015, author = {Wehrle, Esther and Liedert, Astrid and Heilmann, Aline and Wehner, Tim and Bindl, Ronny and Fischer, Lena and Haffner-Luntzer, Melanie and Jakob, Franz and Schinke, Thorsten and Amling, Michael and Ignatius, Anita}, title = {The impact of low-magnitude high-frequency vibration on fracture healing is profoundly influenced by the oestrogen status in mice}, series = {Disease Models \& Mechanisms}, volume = {8}, journal = {Disease Models \& Mechanisms}, doi = {10.1242/dmm.018622}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-121109}, pages = {93-104}, year = {2015}, abstract = {Fracture healing is impaired in aged and osteoporotic individuals. Because adequate mechanical stimuli are able to increase bone formation, one therapeutical approach to treat poorly healing fractures could be the application of whole-body vibration, including low-magnitude high-frequency vibration (LMHFV). We investigated the effects of LMHFV on fracture healing in aged osteoporotic mice. Female C57BL/6NCrl mice (n=96) were either ovariectomised (OVX) or sham operated (non-OVX) at age 41 weeks. When aged to 49 weeks, all mice received a femur osteotomy that was stabilised using an external fixator. The mice received whole-body vibrations (20 minutes/day) with 0.3 G: peak-to-peak acceleration and a frequency of 45 Hz. After 10 and 21 days, the osteotomised femurs and intact bones (contra-lateral femurs, lumbar spine) were evaluated using bending-testing, micro-computed tomography (μCT), histology and gene expression analyses. LMHFV disturbed fracture healing in aged non-OVX mice, with significantly reduced flexural rigidity (-81\%) and bone formation (-80\%) in the callus. Gene expression analyses demonstrated increased oestrogen receptor β (ERβ, encoded by Esr2) and Sost expression in the callus of the vibrated animals, but decreased β-catenin, suggesting that ERβ might mediate these negative effects through inhibition of osteoanabolic Wnt/β-catenin signalling. In contrast, in OVX mice, LMHFV significantly improved callus properties, with increased flexural rigidity (+1398\%) and bone formation (+637\%), which could be abolished by subcutaneous oestrogen application (0.025 mg oestrogen administered in a 90-day-release pellet). On a molecular level, we found an upregulation of ERα in the callus of the vibrated OVX mice, whereas ERβ was unaffected, indicating that ERα might mediate the osteoanabolic response. Our results indicate a major role for oestrogen in the mechanostimulation of fracture healing and imply that LMHFV might only be safe and effective in confined target populations.}, language = {en} } @article{BoelchJansenMeffertetal.2015, author = {Boelch, S. P. and Jansen, H. and Meffert, R. H. and Frey, S. P.}, title = {Six Sesamoid Bones on Both Feet: Report of a Rare Case}, series = {Journal of Clinical and Diagnostic Research}, volume = {9}, journal = {Journal of Clinical and Diagnostic Research}, number = {8}, doi = {10.7860/JCDR/2015/12842.6394}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126073}, pages = {RD04-RD05}, year = {2015}, abstract = {There is a variation of the total number of distinct bones in the human in the literature. This difference is mainly caused by the variable existence of sesamoid bones. Sesamoid bones at the first MTP are seen regularly. In contrast additional sesamoid bones at the divond to fifth MTP are rare. We report a case of additional sesamoid bones at every metatarsophalangeal joint (MTP) of both feet. A 22-year-old female Caucasian presented with weight-dependent pain of the divond MTP of the left foot. In the radiographs of both feet additional sesamoid bones at every MTP could be seen. This case reports a very rare variation in human anatomy. A similar case has not been displayed to the academic society and therefore should be acknowledged.}, language = {en} } @article{JakobEbertRudertetal.2012, author = {Jakob, Franz and Ebert, Regina and Rudert, Maximilian and N{\"o}th, Ulrich and Walles, Heike and Docheva, Denitsa and Schieker, Matthias and Meinel, Lorenz and Groll, J{\"u}rgen}, title = {In situ guided tissue regeneration in musculoskeletal diseases and aging}, series = {Cell and Tissue Research}, volume = {347}, journal = {Cell and Tissue Research}, number = {3}, doi = {10.1007/s00441-011-1237-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-124738}, pages = {725-735}, year = {2012}, abstract = {In situ guided tissue regeneration, also addressed as in situ tissue engineering or endogenous regeneration, has a great potential for population-wide "minimal invasive" applications. During the last two decades, tissue engineering has been developed with remarkable in vitro and preclinical success but still the number of applications in clinical routine is extremely small. Moreover, the vision of population-wide applications of ex vivo tissue engineered constructs based on cells, growth and differentiation factors and scaffolds, must probably be deemed unrealistic for economic and regulation-related issues. Hence, the progress made in this respect will be mostly applicable to a fraction of post-traumatic or post-surgery situations such as big tissue defects due to tumor manifestation. Minimally invasive procedures would probably qualify for a broader application and ideally would only require off the shelf standardized products without cells. Such products should mimic the microenvironment of regenerating tissues and make use of the endogenous tissue regeneration capacities. Functionally, the chemotaxis of regenerative cells, their amplification as a transient amplifying pool and their concerted differentiation and remodeling should be addressed. This is especially important because the main target populations for such applications are the elderly and diseased. The quality of regenerative cells is impaired in such organisms and high levels of inhibitors also interfere with regeneration and healing. In metabolic bone diseases like osteoporosis, it is already known that antagonists for inhibitors such as activin and sclerostin enhance bone formation. Implementing such strategies into applications for in situ guided tissue regeneration should greatly enhance the efficacy of tailored procedures in the future.}, language = {en} } @article{WalshLemsKarrasetal.2012, author = {Walsh, J. Bernard and Lems, Willem F. and Karras, Dimitrios and Langdahl, Bente L. and Ljunggren, Osten and Fahrleitner-Pammer, Astrid and Barrett, Annabel and Rajzbaum, Gerald and Jakob, Franz and Marin, Fernando}, title = {Effectiveness of Teriparatide in Women Over 75 Years of Age with Severe Osteoporosis: 36-Month Results from the European Forsteo Observational Study (EFOS)}, series = {Calcified Tissue International}, volume = {90}, journal = {Calcified Tissue International}, number = {5}, doi = {10.1007/s00223-012-9590-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-124746}, pages = {373-383}, year = {2012}, abstract = {This predefined analysis of the European Forsteo Observational Study (EFOS) aimed to describe clinical fracture incidence, back pain, and health-related quality of life (HRQoL) during 18 months of teriparatide treatment and 18 months post-teriparatide in the subgroup of 589 postmenopausal women with osteoporosis aged ≥75 years. Data on clinical fractures, back pain (visual analogue scale, VAS), and HRQoL (EQ-5D) were collected over 36 months. Fracture data were summarized in 6-month intervals and analyzed using logistic regression with repeated measures. A repeated-measures model analyzed changes from baseline in back pain VAS and EQ-VAS. During the 36-month observation period, 87 (14.8 \%) women aged ≥75 years sustained a total of 111 new fractures: 37 (33.3 \%) vertebral fractures and 74 (66.7 \%) nonvertebral fractures. Adjusted odds of fracture was decreased by 80 \% in the 30 to <36-month interval compared with the first 6-month interval (P < 0.009). Although the older subgroup had higher back pain scores and poorer HRQoL at baseline than the younger subgroup, both age groups showed significant reductions in back pain and improvements in HRQoL postbaseline. In conclusion, women aged ≥75 years with severe postmenopausal osteoporosis treated with teriparatide in normal clinical practice showed a reduced clinical fracture incidence by 30 months compared with baseline. An improvement in HRQoL and, possibly, an early and significant reduction in back pain were also observed, which lasted for at least 18 months after teriparatide discontinuation when patients were taking other osteoporosis medication. The results should be interpreted in the context of an uncontrolled observational study.}, language = {en} } @phdthesis{Simann2015, author = {Simann, Meike}, title = {Aufkl{\"a}rung der Effekte von Fibroblasten-Wachstumsfaktor 1 und 2 auf die Adipogenese und Osteogenese von prim{\"a}ren humanen Knochenmark-Stroma-Zellen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-119322}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2015}, abstract = {Regulating and reverting the adipo-osteogenic lineage decision of trabecular human bone marrow stromal cells (hBMSCs) represents a promising approach for osteoporosis therapy and prevention. Fibroblast growth factor 1 (FGF1) and its subfamily member FGF2 were scored as lead candidates to exercise control over lineage switching processes (conversion) in favor of osteogenesis previously. However, their impact on differentiation events is controversially discussed in literature. Hence, the present study aimed to investigate the effects of these FGFs on the adipogenic and osteogenic differentiation and conversion of primary hBMSCs. Moreover, involved downstream signaling mechanisms should be elucidated and, finally, the results should be evaluated with regard to the possible therapeutic approach. This study clearly revealed that culture in the presence of FGF1 strongly prevented the adipogenic differentiation of hBMSCs as well as the adipogenic conversion of pre-differentiated osteoblastic cells. Lipid droplet formation was completely inhibited by a concentration of 25 ng/µL. Meanwhile, the expression of genetic markers for adipogenic initiation, peroxisome proliferator-activated receptor gamma 2 (PPARg2) and CCAAT/enhancer binding protein alpha (C/EBPa), as well as subsequent adipocyte maturation, fatty acid binding protein 4 (FABP4) and lipoprotein lipase (LPL), were significantly downregulated. Yet, the genetic markers of osteogenic commitment and differentiation were not upregulated during adipogenic differentiation and conversion under FGF supplementation, not supporting an event of osteogenic lineage switching. Moreover, when examining the effects on the osteogenic differentiation of hBMSCs and the osteogenic conversion of pre-differentiated adipocytic cells, culture in the presence of FGF1 markedly decreased extracellular matrix (ECM) mineralization. Additionally, the gene expression of the osteogenic marker alkaline phosphatase (ALP) was significantly reduced and ALP enzyme activity was decreased. Furthermore, genetic markers of osteogenic commitment, like the master regulator runt-related transcription factor 2 (RUNX2) and bone morphogenetic protein 4 (BMP4), as well as markers of osteogenic differentiation and ECM formation, like collagen 1 A1 (COL1A1) and integrin-binding sialoprotein (IBSP), were downregulated. In contrast, genes known to inhibit ECM mineralization, like ANKH inorganic pyrophosphate transport regulator (ANKH) and osteopontin (OPN), were upregulated. ANKH inhibition revealed that its transcriptional elevation was not crucial for the reduced matrix mineralization, perhaps due to decreased expression of ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) that likely annulled ANKH upregulation. Like FGF1, also the culture in the presence of FGF2 displayed a marked anti-adipogenic and anti-osteogenic effect. The FGF receptor 1 (FGFR1) was found to be crucial for mediating the described FGF effects in adipogenic and osteogenic differentiation and conversion. Yet, adipogenic conversion displayed a lower involvement of the FGFR1. For adipogenic differentiation and osteogenic differentiation/conversion, downstream signal transduction involved the extracellular signal-regulated kinases 1 and 2 (ERK1/2) and the mitogen-activated protein kinase (MAPK)/ERK kinases 1 and 2 (MEK1/2), probably via the phosphorylation of FGFR docking protein FGFR substrate 2a (FRS2a) and its effector Ras/MAPK. The c-Jun N-terminal kinase (JNK), p38-MAPK, and protein kinase C (PKC) were not crucial for the signal transduction, yet were in part responsible for the rate of adipogenic and/or osteogenic differentiation itself, in line with current literature. Taken together, to the best of our knowledge, our study was the first to describe the strong impact of FGF1 and FGF2 on both the adipogenic and osteogenic differentiation and conversion processes of primary hBMSCs in parallel. It clearly revealed that although both FGFs were not able to promote the differentiation and lineage switching towards the osteogenic fate, they strongly prevented adipogenic differentiation and lineage switching, which seem to be elevated during osteoporosis. Our findings indicate that FGF1 and FGF2 entrapped hBMSCs in a pre-committed state. In conclusion, these agents could be applied to potently prevent unwanted adipogenesis in vitro. Moreover, our results might aid in unraveling a pharmacological control point to eliminate the increased adipogenic differentiation and conversion as potential cause of adipose tissue accumulation and decreased osteoblastogenesis in bone marrow during aging and especially in osteoporosis.}, subject = {Mesenchymzelle}, language = {en} } @article{SeefriedDahirPetryketal.2020, author = {Seefried, Lothar and Dahir, Kathryn and Petryk, Anna and H{\"o}gler, Wolfgang and Linglart, Agn{\`e}s and Martos-Moreno, Gabriel {\´A}ngel and Ozono, Keiichi and Fang, Shona and Rockman-Greenberg, Cheryl and Kishnani, Priya S}, title = {Burden of Illness in Adults With Hypophosphatasia: Data From the Global Hypophosphatasia Patient Registry}, series = {Journal of Bone and Mineral Research}, volume = {35}, journal = {Journal of Bone and Mineral Research}, number = {11}, doi = {10.1002/jbmr.4130}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-217787}, pages = {2171 -- 2178}, year = {2020}, abstract = {Hypophosphatasia (HPP) is a rare, inherited, metabolic disease caused by deficient tissue non-specific alkaline phosphatase activity. This study aims to assess patient-reported pain, disability and health-related quality of life (HRQoL) in a real-world cohort of adults with HPP who were not receiving asfotase alfa during the analysis. Adults (≥18 years old) with HPP (confirmed by ALPL gene mutation and/or low serum alkaline phosphatase activity for age/sex) were identified from the Global HPP Registry (NCT02306720). Demographics, clinical characteristics, and data on patient-reported pain, disability, and HRQoL (assessed by Brief Pain Inventory Short Form [BPI-SF], Health Assessment Questionnaire Disability Index [HAQ-DI], and 36-Item Short-Form Health Survey version 2 [SF-36v2], respectively) were stratified by pediatric- and adult-onset HPP and summarized descriptively. Of the 304 adults included (median [min, max] age 48.6 [18.8, 79.8] years; 74\% women), 45\% had adult-onset HPP and 33\% had pediatric-onset HPP (unknown age of onset, 22\%). Of those with data, 38\% had experienced ≥5 HPP manifestations and 62\% had a history of ≥1 fracture/pseudofracture. Median (Q1, Q3) BPI-SF scores were 3.5 (1.5, 5.3) for pain severity and 3.3 (0.9, 6.2) for pain interference. Median (Q1, Q3) disability on the HAQ-DI was 0.3 (0.0, 0.7). Median (Q1, Q3) physical and mental component summary scores on the SF-36v2 were 42.4 (32.7, 49.9) and 45.3 (36.3, 54.8), respectively. Greater numbers of HPP manifestations experienced/body systems affected correlated significantly with poorer scores on the BPI-SF, HAQ-DI, and SF-36v2 (all p < 0.05). No significant differences between adults with pediatric- and adult-onset HPP were observed for patient-reported outcomes, except for disability and the BPI-SF question "pain at its worst," which were significantly higher among adults with pediatric- versus adult-onset HPP (p = 0.03 and 0.04, respectively). These data from the Global HPP Registry show that adults with HPP have a substantial burden of illness that is associated with reduced patient-reported HRQoL, regardless of age of disease onset.}, language = {en} } @article{WagenbrennerHeinzHorasetal.2020, author = {Wagenbrenner, Mike and Heinz, Tizian and Horas, Konstantin and Jakuscheit, Axel and Arnholdt, Joerg and Mayer-Wagner, Susanne and Rudert, Maximilian and Holzapfel, Boris M. and Weißenberger, Manuel}, title = {Impact of Tranexamic Acid on Chondrocytes and Osteogenically Differentiated Human Mesenchymal Stromal Cells (hMSCs) In Vitro}, series = {Journal of Clinical Medicine}, volume = {9}, journal = {Journal of Clinical Medicine}, number = {12}, issn = {2077-0383}, doi = {10.3390/jcm9123880}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-219410}, year = {2020}, abstract = {The topical application of tranexamic acid (TXA) helps to prevent post-operative blood loss in total joint replacements. Despite these findings, the effects on articular and periarticular tissues remain unclear. Therefore, this in vitro study examined the effects of varying exposure times and concentrations of TXA on proliferation rates, gene expression and differentiation capacity of chondrocytes and human mesenchymal stromal cells (hMSCs), which underwent osteogenic differentiation. Chondrocytes and hMSCs were isolated and multiplied in monolayer cell cultures. Osteogenic differentiation of hMSCs was induced for 21 days using a differentiation medium containing specific growth factors. Cell proliferation was analyzed using ATP assays. Effects of TXA on cell morphology were examined via light microscopy and histological staining, while expression levels of tissue-specific genes were measured using semiquantitative RT-PCR. After treatment with 50 mg/mL of TXA, a decrease in cell proliferation rates was observed. Furthermore, treatment with concentrations of 20 mg/mL of TXA for at least 48 h led to a visible detachment of chondrocytes. TXA treatment with 50 mg/mL for at least 24 h led to a decrease in the expression of specific marker genes in chondrocytes and osteogenically differentiated hMSCs. No significant effects were observed for concentrations beyond 20 mg/mL of TXA combined with exposure times of less than 24 h. This might therefore represent a safe limit for topical application in vivo. Further research regarding in vivo conditions and effects on hMSC functionality are necessary to fully determine the effects of TXA on articular and periarticular tissues.}, language = {en} } @article{RackwitzEdenReppenhagenetal.2012, author = {Rackwitz, Lars and Eden, Lars and Reppenhagen, Stephan and Reichert, Johannes C. and Jakob, Franz and Walles, Heike and Pullig, Oliver and Tuan, Rocky S. and Rudert, Maximilian and N{\"o}th, Ulrich}, title = {Stem cell- and growth factor-based regenerative therapies for avascular necrosis of the femoral head}, series = {Stem Cell Research \& Therapy}, volume = {3}, journal = {Stem Cell Research \& Therapy}, number = {7}, doi = {10.1186/scrt98}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-135413}, year = {2012}, abstract = {Avascular necrosis (AVN) of the femoral head is a debilitating disease of multifactorial genesis, predominately affects young patients, and often leads to the development of secondary osteoarthritis. The evolving field of regenerative medicine offers promising treatment strategies using cells, biomaterial scaffolds, and bioactive factors, which might improve clinical outcome. Early stages of AVN with preserved structural integrity of the subchondral plate are accessible to retrograde surgical procedures, such as core decompression to reduce the intraosseous pressure and to induce bone remodeling. The additive application of concentrated bone marrow aspirates, ex vivo expanded mesenchymal stem cells, and osteogenic or angiogenic growth factors (or both) holds great potential to improve bone regeneration. In contrast, advanced stages of AVN with collapsed subchondral bone require an osteochondral reconstruction to preserve the physiological joint function. Analogously to strategies for osteochondral reconstruction in the knee, anterograde surgical techniques, such as osteochondral transplantation (mosaicplasty), matrix-based autologous chondrocyte implantation, or the use of acellular scaffolds alone, might preserve joint function and reduce the need for hip replacement. This review summarizes recent experimental accomplishments and initial clinical findings in the field of regenerative medicine which apply cells, growth factors, and matrices to address the clinical problem of AVN.}, language = {en} } @article{GroteNoeldekeBlauthetal.2013, author = {Grote, Stefan and Noeldeke, Tatjana and Blauth, Michael and Mutschler, Wolf and B{\"u}rklein, Dominik}, title = {Mechanical torque measurement in the proximal femur correlates to failure load and bone mineral density ex vivo}, series = {Orthopedic Reviews (Pavia)}, volume = {5}, journal = {Orthopedic Reviews (Pavia)}, number = {e16}, doi = {10.4081/or.2013.e16}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-132358}, year = {2013}, abstract = {Knowledge of local bone quality is essential for surgeons to determine operation techniques. A device for intraoperative measurement of local bone quality has been developed by the AO-Research Foundation (DensiProbe®). We used this device to experimentally measure peak breakaway torque of trabecular bone in the proximal femur and correlated this with local bone mineral density (BMD) and failure load. Bone mineral density of 160 cadaver femurs was measured by ex situ dual-energy X-ray absorptiometry. The failure load of all femurs was analyzed by side-impact analysis. Femur fractures were fixed and mechanical peak torque was measured with the DensiProbe® device. Correlation was calculated whereas correlation coefficient and significance was calculated by Fisher's Z-transformation. Moreover, linear regression analysis was carried out. The unpaired Student's t-test was used to assess the significance of differences. The Ward triangle region had the lowest BMD with 0.511 g/cm2 (±0.17 g/cm2), followed by the upper neck region with 0.546 g/cm2 (±0.16 g/cm2), trochanteric region with 0.685 g/cm2 (±0.19 g/cm2) and the femoral neck with 0.813 g/cm2 (±0.2 g/cm2). Peak torque of DensiProbe® in the femoral head was 3.48 Nm (±2.34 Nm). Load to failure was 4050.2 N (±1586.7 N). The highest correlation of peak torque measured by Densi Probe® and load to failure was found in the femoral neck (r=0.64, P<0.001). The overall correlation of mechanical peak torque with T-score was r=0.60 (P<0.001). A correlation was found between mechanical peak torque, load to failure of bone and BMD in vitro. Trabecular strength of bone and bone mineral density are different aspects of bone strength, but a correlation was found between them. Mechanical peak torque as measured may contribute additional information about bone strength, especially in the perioperative testing.}, language = {en} } @article{BenischSchillingKleinHitpassetal.2012, author = {Benisch, Peggy and Schilling, Tatjana and Klein-Hitpass, Ludger and Frey, S{\"o}nke P. and Seefried, Lothar and Raaijmakers, Nadja and Krug, Melanie and Regensburger, Martina and Zeck, Sabine and Schinke, Thorsten and Amling, Michael and Ebert, Amling and Jakob, Franz}, title = {The Transcriptional Profile of Mesenchymal Stem Cell Populations in Primary Osteoporosis Is Distinct and Shows Overexpression of Osteogenic Inhibitors}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {9}, doi = {10.1371/journal.pone.0045142}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133379}, pages = {e45142}, year = {2012}, abstract = {Primary osteoporosis is an age-related disease characterized by an imbalance in bone homeostasis. While the resorptive aspect of the disease has been studied intensely, less is known about the anabolic part of the syndrome or presumptive deficiencies in bone regeneration. Multipotent mesenchymal stem cells (MSC) are the primary source of osteogenic regeneration. In the present study we aimed to unravel whether MSC biology is directly involved in the pathophysiology of the disease and therefore performed microarray analyses of hMSC of elderly patients (79-94 years old) suffering from osteoporosis (hMSC-OP). In comparison to age-matched controls we detected profound changes in the transcriptome in hMSC-OP, e.g. enhanced mRNA expression of known osteoporosis-associated genes (LRP5, RUNX2, COL1A1) and of genes involved in osteoclastogenesis (CSF1, PTH1R), but most notably of genes coding for inhibitors of WNT and BMP signaling, such as Sclerostin and MAB21L2. These candidate genes indicate intrinsic deficiencies in self-renewal and differentiation potential in osteoporotic stem cells. We also compared both hMSC-OP and non-osteoporotic hMSC-old of elderly donors to hMSC of similar to 30 years younger donors and found that the transcriptional changes acquired between the sixth and the ninth decade of life differed widely between osteoporotic and non-osteoporotic stem cells. In addition, we compared the osteoporotic transcriptome to long term-cultivated, senescent hMSC and detected some signs for pre-senescence in hMSC-OP. Our results suggest that in primary osteoporosis the transcriptomes of hMSC populations show distinct signatures and little overlap with non-osteoporotic aging, although we detected some hints for senescence-associated changes. While there are remarkable inter-individual variations as expected for polygenetic diseases, we could identify many susceptibility genes for osteoporosis known from genetic studies. We also found new candidates, e.g. MAB21L2, a novel repressor of BMP-induced transcription. Such transcriptional changes may reflect epigenetic changes, which are part of a specific osteoporosis-associated aging process.}, language = {en} } @article{KlotzMentrupRegensburgeretal.2012, author = {Klotz, Barbara and Mentrup, Birgit and Regensburger, Martina and Zeck, Sabine and Schneidereit, Jutta and Schupp, Nicole and Linden, Christian and Merz, Cornelia and Ebert, Regina and Jakob, Franz}, title = {1,25-Dihydroxyvitamin D3 Treatment Delays Cellular Aging in Human Mesenchymal Stem Cells while Maintaining Their Multipotent Capacity}, series = {PLoS ONE}, volume = {7}, journal = {PLoS ONE}, number = {1}, doi = {10.1371/journal.pone.0029959}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133392}, pages = {e29959}, year = {2012}, abstract = {1,25-dihydroxyvitamin D3 (1,25D3) was reported to induce premature organismal aging in fibroblast growth factor-23 (Fgf23) and klotho deficient mice, which is of main interest as 1,25D3 supplementation of its precursor cholecalciferol is used in basic osteoporosis treatment. We wanted to know if 1,25D3 is able to modulate aging processes on a cellular level in human mesenchymal stem cells (hMSC). Effects of 100 nM 1,25D3 on hMSC were analyzed by cell proliferation and apoptosis assay, beta-galactosidase staining, VDR and surface marker immunocytochemistry, RT-PCR of 1,25D3-responsive, quiescence-and replicative senescence-associated genes. 1,25D3 treatment significantly inhibited hMSC proliferation and apoptosis after 72 h and delayed the development of replicative senescence in long-term cultures according to beta-galactosidase staining and P16 expression. Cell morphology changed from a fibroblast like appearance to broad and rounded shapes. Long term treatment did not induce lineage commitment in terms of osteogenic pathways but maintained their clonogenic capacity, their surface marker characteristics (expression of CD73, CD90, CD105) and their multipotency to develop towards the chondrogenic, adipogenic and osteogenic pathways. In conclusion, 1,25D3 delays replicative senescence in primary hMSC while the pro-aging effects seen in mouse models might mainly be due to elevated systemic phosphate levels, which propagate organismal aging.}, language = {en} } @article{RudertHolzapfelJakubietz2011, author = {Rudert, Maximilian and Holzapfel, Boris Michael and Jakubietz, Michael}, title = {Adjuvant Radiotherapy}, series = {Deutsches {\"A}rzteblatt International}, volume = {108}, journal = {Deutsches {\"A}rzteblatt International}, number = {33}, doi = {10.3238/arztebl.2011.0553a}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133571}, pages = {553}, year = {2011}, abstract = {No abstract available.}, language = {en} } @article{HolzapfelChhayaMelchelsetal.2013, author = {Holzapfel, Boris Michael and Chhaya, Mohit Prashant and Melchels, Ferry Petrus Wilhelmus and Holzapfel, Nina Pauline and Prodinger, Peter Michael and von Eisenhart-Rothe, R{\"u}diger and Griensven, Martijn van and Schantz, Jan-Thorsten and Rudert, Maximilian and Hutmacher, Dietmar Werner}, title = {Can Bone Tissue Engineering Contribute to Therapy Concepts after Resection of Musculoskeletal Sarcoma?}, series = {Sarcoma}, volume = {2013}, journal = {Sarcoma}, number = {Article ID 153640}, doi = {10.1155/2013/153640}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-132465}, pages = {10 p.}, year = {2013}, abstract = {Resection of musculoskeletal sarcoma can result in large bone defects where regeneration is needed in a quantity far beyond the normal potential of self-healing. In many cases, these defects exhibit a limited intrinsic regenerative potential due to an adjuvant therapeutic regimen, seroma, or infection. Therefore, reconstruction of these defects is still one of the most demanding procedures in orthopaedic surgery. The constraints of common treatment strategies have triggered a need for new therapeutic concepts to design and engineer unparalleled structural and functioning bone grafts. To satisfy the need for long-term repair and good clinical outcome, a paradigm shift is needed from methods to replace tissues with inert medical devices to more biological approaches that focus on the repair and reconstruction of tissue structure and function. It is within this context that the field of bone tissue engineering can offer solutions to be implemented into surgical therapy concepts after resection of bone and soft tissue sarcoma. In this paper we will discuss the implementation of tissue engineering concepts into the clinical field of orthopaedic oncology.}, language = {en} } @article{WernerBoehmGohlke2013, author = {Werner, Birgit S. and Boehm, Dorota and Gohlke, Frank}, title = {Revision to reverse shoulder arthroplasty with retention of the humeral component Good outcome in 14 patients followed for a mean of 2.5 years}, series = {Acta Orthopaedica}, volume = {84}, journal = {Acta Orthopaedica}, number = {5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131621}, pages = {473-478}, year = {2013}, abstract = {Background: Revision in failed shoulder arthroplasty often requires removal of the humeral component with a significant risk of fracture and bone loss. Newer modular systems allow conversion from anatomic to reverse shoulder arthroplasty with retention of a well-fixed humeral stem. We report on a prospectively evaluated series of conversions from hemiarthroplasty to reverse shoulder arthroplasty. Methods: In 14 cases of failed hemiarthroplasty due to rotator cuff deficiency and painful pseudoparalysis (in 13 women), revision to reverse shoulder arthroplasty was performed between October 2006 and 2010, with retention of the humeral component using modular systems. Mean age at the time of operation was 70 (56-80) years. Pre- and postoperative evaluation followed a standardized protocol including Constant score, range of motion, and radiographic analysis. Mean follow-up time was 2.5 (2-5.5) years. Results: Mean Constant score improved from 9 (2-16) to 41 (17-74) points. Mean lengthening of the arm was 2.6 (0.9-4.7) cm without any neurological complications. One patient required revision due to infection. Interpretation Modular systems allow retainment of a well-fixed humeral stem with good outcome. There is a risk of excessive humeral lengthening.}, language = {en} } @article{LiedertRoentgenSchinkeetal.2014, author = {Liedert, Astrid and R{\"o}ntgen, Viktoria and Schinke, Thorsten and Benisch, Peggy and Ebert, Regina and Jakob, Franz and Klein-Hitpass, Ludger and Lennerz, Jochen K. and Amling, Michael and Ignatius, Anita}, title = {Osteoblast-Specific Krm2 Overexpression and Lrp5 Deficiency Have Different Effects on Fracture Healing in Mice}, series = {PLOS ONE}, volume = {9}, journal = {PLOS ONE}, number = {7}, issn = {1932-6203}, doi = {10.1371/journal.pone.0103250}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-115782}, pages = {e103250}, year = {2014}, abstract = {The canonical Wnt/beta-catenin pathway plays a key role in the regulation of bone remodeling in mice and humans. Two transmembrane proteins that are involved in decreasing the activity of this pathway by binding to extracellular antagonists, such as Dickkopf 1 (Dkk1), are the low-density lipoprotein receptor related protein 5 (Lrp5) and Kremen 2 (Krm2). Lrp 5 deficiency (Lrp5(-/-)) as well as osteoblast-specific overexpression of Krm2 in mice (Col1a1-Krm2) result in severe osteoporosis occurring at young age. In this study, we analyzed the influence of Lrp5 deficiency and osteoblast-specific overexpression of Krm2 on fracture healing in mice using flexible and semi-rigid fracture fixation. We demonstrated that fracture healing was highly impaired in both mouse genotypes, but that impairment was more severe in Col1a1-Krm2 than in Lrp5(-/-) mice and particularly evident in mice in which the more flexible fixation was used. Bone formation was more reduced in Col1a1-Krm2 than in Lrp5(-/-) mice, whereas osteoclast number was similarly increased in both genotypes in comparison with wild-type mice. Using microarray analysis we identified reduced expression of genes mainly involved in osteogenesis that seemed to be responsible for the observed stronger impairment of healing in Col1a1-Krm2 mice. In line with these findings, we detected decreased expression of sphingomyelin phosphodiesterase 3 (Smpd3) and less active beta-catenin in the calli of Col1a1-Krm2 mice. Since Krm2 seems to play a significant role in regulating bone formation during fracture healing, antagonizing KRM2 might be a therapeutic option to improve fracture healing under compromised conditions, such as osteoporosis.}, language = {en} } @article{StaabHottowitzSohnsetal.2014, author = {Staab, Wieland and Hottowitz, Ralf and Sohns, Christian and Sohns, Jan Martin and Gilbert, Fabian and Menke, Jan and Niklas, Andree and Lotz, Joachim}, title = {Accelerometer and Gyroscope Based Gait Analysis Using Spectral Analysis of Patients with Osteoarthritis of the Knee}, series = {Journal of Physical Therapy Science}, volume = {26}, journal = {Journal of Physical Therapy Science}, number = {7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-115907}, pages = {997-1002}, year = {2014}, abstract = {[Purpose] A wide variety of accelerometer tools are used to estimate human movement, but there are no adequate data relating to gait symmetry parameters in the context of knee osteoarthritis. This study's purpose was to evaluate a 3D-kinematic system using body-mounted sensors (gyroscopes and accelerometers) on the trunk and limbs. This is the first study to use spectral analysis for data post processing. [Subjects] Twelve patients with unilateral knee osteoarthritis (OA) (10 male) and seven age-matched controls (6 male) were studied. [Methods] Measurements with 3-D accelerometers and gyroscopes were compared to video analysis with marker positions tracked by a six-camera optoelectronic system (VICON 460, Oxford Metrics). Data were recorded using the 3D-kinematic system. [Results] The results of both gait analysis systems were significantly correlated. Five parameters were significantly different between the knee OA and control groups. To overcome time spent in expensive post-processing routines, spectral analysis was performed for fast differentiation between normal gait and pathological gait signals using the 3D-kinematic system. [Conclusions] The 3D-kinematic system is objective, inexpensive, accurate and portable, and allows long-term recordings in clinical, sport as well as ergonomic or functional capacity evaluation (FCE) settings. For fast post-processing, spectral analysis of the recorded data is recommended.}, language = {en} } @article{ThibaudeauTaubenbergerHolzapfeletal.2014, author = {Thibaudeau, Laure and Taubenberger, Anna V. and Holzapfel, Boris M. and Quent, Verena M. and Fuehrmann, Tobias and Hesami, Parisa and Brown, Toby D. and Dalton, Paul D. and Power, Carl A. and Hollier, Brett G. and Hutmacher, Dietmar W.}, title = {A tissue-engineered humanized xenograft model of human breast cancer metastasis to bone}, series = {Disease Models \& Mechanisms}, volume = {7}, journal = {Disease Models \& Mechanisms}, number = {2}, doi = {10.1242/dmm.014076}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-117466}, pages = {299-309}, year = {2014}, abstract = {The skeleton is a preferred homing site for breast cancer metastasis. To date, treatment options for patients with bone metastases are mostly palliative and the disease is still incurable. Indeed, key mechanisms involved in breast cancer osteotropism are still only partially understood due to the lack of suitable animal models to mimic metastasis of human tumor cells to a human bone microenvironment. In the presented study, we investigate the use of a human tissue-engineered bone construct to develop a humanized xenograft model of breast cancer-induced bone metastasis in a murine host. Primary human osteoblastic cell-seeded melt electrospun scaffolds in combination with recombinant human bone morphogenetic protein 7 were implanted subcutaneously in non-obese diabetic/severe combined immunodeficient mice. The tissue-engineered constructs led to the formation of a morphologically intact 'organ' bone incorporating a high amount of mineralized tissue, live osteocytes and bone marrow spaces. The newly formed bone was largely humanized, as indicated by the incorporation of human bone cells and human-derived matrix proteins. After intracardiac injection, the dissemination of luciferase-expressing human breast cancer cell lines to the humanized bone ossicles was detected by bioluminescent imaging. Histological analysis revealed the presence of metastases with clear osteolysis in the newly formed bone. Thus, human tissue-engineered bone constructs can be applied efficiently as a target tissue for human breast cancer cells injected into the blood circulation and replicate the osteolytic phenotype associated with breast cancer-induced bone lesions. In conclusion, we have developed an appropriate model for investigation of species-specific mechanisms of human breast cancer-related bone metastasis in vivo.}, language = {en} } @article{WirtzGraviusAscherletal.2014, author = {Wirtz, Dieter C. and Gravius, Sascha and Ascherl, Rudolf and Thorweihe, Miguel and Forst, Raimund and Noeth, Ulrich and Maus, Uwe M. and Wimmer, Matthias D. and Zeiler, Guenther and Deml, Moritz C.}, title = {Uncemented femoral revision arthroplasty using a modular tapered, fluted titanium stem 5-to 16-year results of 163 cases}, series = {Acta Orthopaedica}, volume = {85}, journal = {Acta Orthopaedica}, number = {6}, issn = {1745-3674}, doi = {10.3109/17453674.2014.958809}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-114555}, pages = {562 - 569}, year = {2014}, abstract = {Background and purpose - Due to the relative lack of reports on the medium- to long-term clinical and radiographic results of modular femoral cementless revision, we conducted this study to evaluate the medium- to long-term results of uncemented femoral stem revisions using the modular MRP-TITAN stem with distal diaphyseal fixation in a consecutive patient series. Patients and methods - We retrospectively analyzed 163 femoral stem revisions performed between 1993 and 2001 with a mean follow-up of 10 (5-16) years. Clinical assessment included the Harris hip score (HHS) with reference to comorbidities and femoral defect sizes classified by Charnley and Paprosky. Intraoperative and postoperative complications were analyzed and the failure rate of the MRP stem for any reason was examined. Results - Mean HHS improved up to the last follow-up (37 (SD 24) vs. 79 (SD 19); p < 0.001). 99 cases (61\%) had extensive bone defects (Paprosky IIB-III). Radiographic evaluation showed stable stem anchorage in 151 cases (93\%) at the last follow-up. 10 implants (6\%) failed for various reasons. Neither a breakage of a stem nor loosening of the morse taper junction was recorded. Kaplan-Meier survival analysis revealed a 10-year survival probability of 97\% (95\% CI: 95-100). Interpretation - This is one of the largest medium- to longterm analyses of cementless modular revision stems with distal diaphyseal anchorage. The modular MRP-TITAN was reliable, with a Kaplan-Meier survival probability of 97\% at 10 years.}, language = {en} } @article{ReichertSchmalzlPrageretal.2013, author = {Reichert, Johannes and Schmalzl, Jonas and Prager, Patrick and Gilbert, Fabian and Quent, Verena M. C. and Steinert, Andre F. and Rudert, Maximilian and N{\"o}th, Ulrich}, title = {Synergistic effect of Indian hedgehog and bone morphogenetic protein-2 gene transfer to increase the osteogenic potential of human mesenchymal stem cells}, series = {Stem Cell Research \& Therapy}, journal = {Stem Cell Research \& Therapy}, doi = {10.1186/scrt316}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97010}, year = {2013}, abstract = {Introduction To stimulate healing of large bone defects research has concentrated on the application of mesenchymal stem cells (MSCs). Methods In the present study, we induced the overexpression of the growth factors bone morphogenetic protein 2 (BMP-2) and/or Indian hedgehog (IHH) in human MSCs by adenoviral transduction to increase their osteogenic potential. GFP and nontransduced MSCs served as controls. The influence of the respective genetic modification on cell metabolic activity, proliferation, alkaline phosphatase (ALP) activity, mineralization in cell culture, and osteogenic marker gene expression was investigated. Results Transduction had no negative influence on cell metabolic activity or proliferation. ALP activity showed a typical rise-and-fall pattern with a maximal activity at day 14 and 21 after osteogenic induction. Enzyme activity was significantly higher in groups cultured with osteogenic media. The overexpression of BMP-2 and especially IHH + BMP-2 resulted in a significantly higher mineralization after 28 days. This was in line with obtained quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) analyses, which showed a significant increase in osteopontin and osteocalcin expression for osteogenically induced BMP-2 and IHH + BMP-2 transduced cells when compared with the other groups. Moreover, an increase in runx2 expression was observed in all osteogenic groups toward day 21. It was again more pronounced for BMP-2 and IHH + BMP-2 transduced cells cultured in osteogenic media. Conclusions In summary, viral transduction did not negatively influence cell metabolic activity and proliferation. The overexpression of BMP-2 in combination with or without IHH resulted in an increased deposition of mineralized extracellular matrix, and expression of osteogenic marker genes. Viral transduction therefore represents a promising means to increase the osteogenic potential of MSCs and the combination of different transgenes may result in synergistic effects.}, language = {en} } @article{EbertDotterweichKrausetal.2014, author = {Ebert, Regina and Dotterweich, Julia and Kraus, Sabrina and Tower, Robert J. and Jakob, Franz and Sch{\"u}tze, Norbert}, title = {Mesenchymal stem cell contact promotes CCN1 splicing and transcription in myeloma cells}, doi = {10.1186/1478-811X-12-36}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-110497}, year = {2014}, abstract = {CCN family member 1 (CCN1), also known as cysteine-rich angiogenic inducer 61 (CYR61), belongs to the extracellular matrix-associated CCN protein family. The diverse functions of these proteins include regulation of cell migration, adhesion, proliferation, differentiation and survival/apoptosis, induction of angiogenesis and cellular senescence. Their functions are partly overlapping, largely non-redundant, cell-type specific, and depend on the local microenvironment. To elucidate the role of CCN1 in the crosstalk between stromal cells and myeloma cells, we performed co-culture experiments with primary mesenchymal stem cells (MSC) and the interleukin-6 (IL-6)-dependent myeloma cell line INA-6. Here we show that INA-6 cells display increased transcription and induction of splicing of intron-retaining CCN1 pre-mRNA when cultured in contact with MSC. Protein analyses confirmed that INA-6 cells co-cultured with MSC show increased levels of CCN1 protein consistent with the existence of a pre-mature stop codon in intron 1 that abolishes translation of unspliced mRNA. Addition of recombinant CCN1-Fc protein to INA-6 cells was also found to induce splicing of CCN1 pre-mRNA in a concentration-dependent manner. Only full length CCN1-Fc was able to induce mRNA splicing of all introns, whereas truncated recombinant isoforms lacking domain 4 failed to induce intron splicing. Blocking RGD-dependent integrins on INA-6 cells resulted in an inhibition of these splicing events. These findings expand knowledge on splicing of the proangiogenic, matricellular factor CCN1 in the tumor microenvironment. We propose that contact with MSC-derived CCN1 leads to splicing and enhanced transcription of CCN1 which further contributes to the translation of angiogenic factor CCN1 in myeloma cells, supporting tumor viability and myeloma bone disease.}, language = {en} } @article{SteinertRudertSieker2014, author = {Steinert, Andre F. and Rudert, Maximilian and Sieker, Jakob T.}, title = {"Symptomatic loosening of a total knee arthroplasty caused by a tibial chondrosarcoma - a case report"}, doi = {10.1186/2193-1801-3-308}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-110341}, year = {2014}, abstract = {Premature implant loosening following total knee arthroplasty (TKA) can have several causes. In this article we report on a rare case of a 74 year old male patient suffering tibial component loosening 14 month after primary TKA. The patient did neither have any malignancies nor joint arthroplasty before. Upon clinical examination the range of motion in the diseased knee was painfully restricted to 80° of knee flexion, with the patient increasingly suffering sleeping and resting pain, and also at weight bearing. In standard radiographs, loosening of the TKA due to a large osteolysis at the tibial component was evident. Local computed tomography (CT) of the right knee revealed loosening of the tibial component due to a presumably malign bone tumor. For determination of the final diagnosis a representative biopsy of the tumor was taken by open surgery prior to the tumor resection. Histopathologic evaluation of the biopsy revealed a periprosthetic myxoid chondrosarcoma of the proximal tibia. Pre-operative staging examination included CT scans of lung and abdomen, as well as a bone scintigraphy which revealed no signs of tumor metastasis in the body. Surgical management comprised wide tumor resection and implantation of a hinged tumor knee arthroplasty with replacements of the distal femur and proximal tibia, as well as a patella tendon replacement using a synthetic ligament. Revision surgery was necessary twice due to impaired wound healing and critical soft tissue coverage, and treatment included a gastrocnemius muscle flap with skin mesh graft covering. Unfortunately long-term follow-up examinations could not be obtained, as the patient deceased due to an alveolitis during rehabilitation. In summary, the specifics of this rare case of aseptic TKA loosening, and the unusual circumstances of chondrosarcoma diagnosis and treatment are informative for those providing surgical treatment of similar cases.}, language = {en} } @article{WagenbrennerMayerWagnerRudertetal.2021, author = {Wagenbrenner, Mike and Mayer-Wagner, Susanne and Rudert, Maximilian and Holzapfel, Boris Michael and Weissenberger, Manuel}, title = {Combinations of hydrogels and mesenchymal stromal cells (MSCs) for cartilage tissue engineering — a review of the literature}, series = {Gels}, volume = {7}, journal = {Gels}, number = {4}, issn = {2310-2861}, doi = {10.3390/gels7040217}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-250177}, year = {2021}, abstract = {Cartilage offers limited regenerative capacity. Cell-based approaches have emerged as a promising alternative in the treatment of cartilage defects and osteoarthritis. Due to their easy accessibility, abundancy, and chondrogenic potential mesenchymal stromal cells (MSCs) offer an attractive cell source. MSCs are often combined with natural or synthetic hydrogels providing tunable biocompatibility, biodegradability, and enhanced cell functionality. In this review, we focused on the different advantages and disadvantages of various natural, synthetic, and modified hydrogels. We examined the different combinations of MSC-subpopulations and hydrogels used for cartilage engineering in preclinical and clinical studies and reviewed the effects of added growth factors or gene transfer on chondrogenesis in MSC-laden hydrogels. The aim of this review is to add to the understanding of the disadvantages and advantages of various combinations of MSC-subpopulations, growth factors, gene transfers, and hydrogels in cartilage engineering.}, language = {en} } @article{WeissenbergerWeissenbergerGilbertetal.2020, author = {Weissenberger, M. and Weissenberger, M. H. and Gilbert, F. and Groll, J. and Evans, C. H. and Steinert, A. F.}, title = {Reduced hypertrophy in vitro after chondrogenic differentiation of adult human mesenchymal stem cells following adenoviral SOX9 gene delivery}, series = {BMC Musculoskeletal Disorders}, volume = {20}, journal = {BMC Musculoskeletal Disorders}, doi = {10.1186/s12891-020-3137-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229232}, year = {2020}, abstract = {Background Mesenchymal stem cell (MSC) based-treatments of cartilage injury are promising but impaired by high levels of hypertrophy after chondrogenic induction with several bone morphogenetic protein superfamily members (BMPs). As an alternative, this study investigates the chondrogenic induction of MSCs via adenoviral gene-delivery of the transcription factor SOX9 alone or in combination with other inducers, and comparatively explores the levels of hypertrophy and end stage differentiation in a pellet culture system in vitro. Methods First generation adenoviral vectors encoding SOX9, TGFB1 or IGF1 were used alone or in combination to transduce human bone marrow-derived MSCs at 5 x 10\(^2\) infectious particles/cell. Thereafter cells were placed in aggregates and maintained for three weeks in chondrogenic medium. Transgene expression was determined at the protein level (ELISA/Western blot), and aggregates were analysed histologically, immunohistochemically, biochemically and by RT-PCR for chondrogenesis and hypertrophy. Results SOX9 cDNA was superior to that encoding TGFB1, the typical gold standard, as an inducer of chondrogenesis in primary MSCs as evidenced by improved lacuna formation, proteoglycan and collagen type II staining, increased levels of GAG synthesis, and expression of mRNAs associated with chondrogenesis. Moreover, SOX9 modified aggregates showed a markedly lower tendency to progress towards hypertrophy, as judged by expression of the hypertrophy markers alkaline phosphatase, and collagen type X at the mRNA and protein levels. Conclusion Adenoviral SOX9 gene transfer induces chondrogenic differentiation of human primary MSCs in pellet culture more effectively than TGFB1 gene transfer with lower levels of chondrocyte hypertrophy after 3 weeks of in vitro culture. Such technology might enable the formation of more stable hyaline cartilage repair tissues in vivo.}, language = {en} } @phdthesis{Schilling2007, author = {Schilling, Tatjana}, title = {Transdifferentiation of Human Mesenchymal Stem Cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-24299}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2007}, abstract = {With ageing, the loss of bone mass correlates with the expansion of adipose tissue in human bone marrow thus facilitating bone-related diseases like osteopenia and osteoporosis. The molecular mechanisms underlying these events are still largely unknown. Reduced osteogenesis and concurrently enhanced adipogenesis might not only occur due to the impairment of conventional osteogenic differentiation originating from mesenchymal stem cells (MSCs). Additionally, transdifferentiation of (pre-)osteoblasts into adipocytes could contribute to the fatty conversion. Therefore, the aim of the present study was to prove the existence of transdifferentiation between the adipogenic and osteogenic lineage and to elucidate molecular mechanisms underlying this phenomenon. At first, a cell culture system of primary human MSCs was established that allowed for differentiation into the adipogenic and osteogenic lineage and proved that the MSC-derived adipocytes and pre-osteoblasts were capable of transdifferentiation (reprogramming) from one into the other lineage. Thereby, lineage-specific markers were completely reversed after reprogramming of pre-osteoblasts into adipocytes. The osteogenic transdifferentiation of adipocytes was slightly less efficient since osteogenic markers were present but the adipogenic ones partly persisted. Hence, plasticity also reached into the differentiation pathways of both lineages and the better performance of adipogenic reprogramming further supported the assumption of its occurrence in vivo. The subsequent examination of gene expression changes by microarray analyses that compared transdifferentiated cells with conventionally differentiated ones revealed high numbers of reproducibly regulated genes shortly after initiation of adipogenic and osteogenic reprogramming. Thereof, many genes were correlated with metabolism, transcription, and signal transduction as FGF, IGF, and Wnt signalling, but only few of the established adipogenesis- and none of the osteogenesis-associated marker genes were detected within 24 h after initiation of transdifferentiation. To find possible key control factors of transdifferentiation amongst the huge amount of regulated genes, a novel bioinformatic scoring scheme was developed that ranked genes due to their potential relevance for reprogramming. Besides the reproducibility and level of their regulation, also the possible reciprocity between the adipogenic and osteogenic transdifferentiation pathway was taken into account. Fibroblast growth factor 1 (FGF1) that ranked as one of the leading candidates to govern reprogramming was proven to inhibit adipogenic differentiation as well as adipogenic transdifferentiation in our cell culture system. Further examination of the FGF signalling pathway and other highly ranked genes could help to better understand the age-related fatty degeneration at the molecular level and therefore provide target molecules for therapeutic modulation of the plasticity of both lineages in order to inhibit adipogenic degeneration and to enhance osteogenesis.}, subject = {Zelldifferenzierung}, language = {en} } @phdthesis{Heymer2008, author = {Heymer, Andrea}, title = {Chondrogenic differentiation of human mesenchymal stem cells and articular cartilage reconstruction}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-29448}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2008}, abstract = {Articular cartilage defects are still one of the major challenges in orthopedic and trauma surgery. Today, autologous chondrocyte transplantation (ACT), as a cell-based therapy, is an established procedure. However, one major limitation of this technique is the loss of the chondrogenic phenotype during expansion. Human mesenchymal stem cells (hMSCs) have an extensive proliferation potential and the capacity to differentiate into chondrocytes when maintained under specific conditions. They are therefore considered as candidate cells for tissue engineering approaches of functional cartilage tissue substitutes. First in this study, hMSCs were embedded in a collagen type I hydrogel to evaluate the cartilaginous construct in vitro. HMSC collagen hydrogels cultivated in different culture media showed always a marked contraction, most pronounced in chondrogenic differentiation medium supplemented with TGF-ß1. After stimulation with chondrogenic factors (dexamethasone and TGF-ß1) hMSCs were able to undergo chondrogenesis when embedded in the collagen type I hydrogel, as evaluated by the temporal induction of cartilage-specific gene expression. Furthermore, the cells showed a chondrocyte-like appearance and were homogeneously distributed within a proteoglycan- and collagen type II-rich extracellular matrix, except a small area in the center of the constructs. In this study, chondrogenic differentiation could not be realized with every hMSC preparation. With the improvement of the culture conditions, e.g. the use of a different FBS lot in the gel fabrication process, a higher amount of cartilage-specific matrix deposition could be achieved. Nevertheless, the large variations in the differentiation capacity display the high donor-to-donor variability influencing the development of a cartilaginous construct. Taken together, the results demonstrate that the collagen type I hydrogel is a suitable carrier matrix for hMSC-based cartilage regeneration therapies which present a promising future alternative to ACT. Second, to further improve the quality of tissue-engineered cartilaginous constructs, mechanical stimulation in specific bioreactor systems are often employed. In this study, the effects of mechanical loading on hMSC differentiation have been examined. HMSC collagen hydrogels were cultured in a defined chondrogenic differentiation medium without TGF-ß1 and subjected to a combined mechanical stimulation protocol, consisting of perfusion and cyclic uniaxial compression. Bioreactor cultivation neither affected overall cell viability nor the cell number in collagen hydrogels. Compared with non-loaded controls, mechanical loading promoted the gene expression of COMP and biglycan and induced an up-regulation of matrix metalloproteinase 3. These results circumstantiate that hMSCs are sensitive to mechanical forces, but their differentiation to chondrocytes could not be induced. Further studies are needed to identify the specific metabolic pathways which are altered by mechanical stimulation. Third, for the development of new cell-based therapies for articular cartilage repair, a reliable cell monitoring technique is required to track the cells in vivo non-invasively and repeatedly. This study aimed at analyzing systematically the performance and biological impact of a simple and efficient labeling protocol for hMSCs. Very small superparamagnetic iron oxide particles (VSOPs) were used as magnetic resonance (MR) contrast agent. Iron uptake was confirmed histologically with prussian blue staining and quantified by mass spectrometry. Compared with unlabeled cells, VSOP-labeling did neither influence significantly the viability nor the proliferation potential of hMSCs. Furthermore, iron incorporation did not affect the differentiation capacity of hMSCs. The efficiency of the labeling protocol was assessed with high resolution MR imaging at 11.7 Tesla. VSOP-labeled hMSCs were visualized in a collagen type I hydrogel indicated by distinct hypointense spots in the MR images, resulting from an iron specific loss of signal intensity. This was confirmed by prussian blue staining. In summary, this labeling technique has great potential to visualize hMSCs and track their migration after transplantation for articular cartilage repair with MR imaging.}, subject = {Gelenkknorpel}, language = {en} } @phdthesis{Schenk2007, author = {Schenk, Rita}, title = {Impact of the CCN-proteins CYR61/CCN1 and WISP3/CCN6 on mesenchymal stem cells and endothelial progenitor cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-27766}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2007}, abstract = {CYR61 and WISP3 belong to the family of CCN-proteins. These proteins are characterised by 10\% cysteine residues whose positions are strictly conserved. The proteins are extracellular signalling molecules that can be associated with the extracellular matrix. CCN-proteins function in a cell- and tissue specific overlapping yet distinct manner. CCN-proteins are expressed and function in several cells and tissues of the musculoskeletal system. In this study the impact of the angiogenic inducer cysteine-rich protein 61 (CYR61/CCN1) on endothelial progenitor cells (EPCs) and mesenchymal stem cells (MSCs) as well as the wnt1 inducible signalling pathway protein 3 (WISP3/CCN6) on MSCs were elucidated. EPCs are promising cells to induce neovascularisation in ischemic regions as tissue engineered constructs. A major drawback is the small amount of cells that can be obtained from patients; therefore a stimulating factor to induce in vitro propagation of EPCs is urgently needed. In this study, mononuclear cells obtained from peripheral blood were treated with 0.5 µg/ml CYR61, resulting in an up to 7-fold increased cell number within one week compared to untreated control cells. To characterise if EPCs treated with CYR61 display altered or maintained EPC phenotype, the expression of the established markers CD34, CD133 and KDR as well as the uptake of acLDL and concurrent staining for ulex lectin was analysed. Both CYR61 treated and untreated control cells displayed EPCs characteristics, indicating that CYR61 treatment induces EPC number without altering their phenotype. Further studies revealed that the stimulating effect of CYR61 on EPCs is due to enhanced adhesion, rather than improved proliferation. Usage of mutated CYR61-proteins showed that the adhesive effect is mediated, at least partly, by the integrin \&\#945;6\&\#946;1, while the integrin \&\#945;\&\#965;\&\#946;3 has no influence. Endogenous expression of CYR61 was not detectable in EPCs, which indicated that control cells are not influenced by endogenous secretion of CYR61 and also could explain the dose-dependent effect of CYR61 that is measured at a low concentration of 0.05 µg/ml. MSCs were treated with 0.5 µg/ml CYR61, a combination of growth factors including VEGF, both together and compared to untreated control cells. Matrigel angiogenesis assay revealed an induction of angiogenesis, detected by induced sprouting of the cells, after CYR61 treatment of the MSC. Induced sprouting and vessel like structure formation after CYR61 treatment was similar to the results obtained after treatment with growth factors including the established angiogenesis inducer VEGF. This result clearly demonstrates the angiogenic potential of CYR61 on MSCs. Further studies revealed a migrative and proliferative effect of CYR61 on MSCs. Both properties are crucial for the induction of angiogenesis thus further strengthening the view of CYR61 as an angiogenic inducer. MSCs and EPCs are promising cells for tissue engineering applications in bone remodelling and reconstruction. MSCs due to their potential to differentiate into other lineages; EPCs induce neovascularisation within the construct. Both cell types respond to CYR61 treatment. Furthermore EPCs home to sides were CYR61 expression is detectable and both are induced by similar stimulators. Therefore CYR61 is a promising factor for tissue engineered bone reconstruction applications. WISP3 is expressed in cartilage in vivo and in chondrocytes in vitro. Loss of function mutations in the WISP3 gene are associated to the inherited human disease progressive pseudorheumatoid dysplasia (PPD), that is characterised by cartilage loss and bone and joint destruction. Since MSCs also express the protein, the aim of this study was to elucidate if recombinant protein targets MSCs. A migratory effect of WISP3 treatment on MSCs and osteogenic differentiated MSCs has been proven in this study. To elucidate if global gene expression patterns are influenced by WISP3, cells were treated with 0.5 µg/ml WISP3 and compared to untreated control MSCs. Gene expression study by using affymetrix technology revealed an induction of interferon inducible genes including CXCL chemokines and members of the TNFSF family. Reevaluation by RT-PCR on identical RNA and an additional time series confirmed the results. Although no established cartilage associated genes were detected as regulated genes within this 24h treatment, anti-angiogenic and immunosuppressive genes indicate a protective role of WISP3 for the cartilage, which is sensitive to inflammatory processes. Both CCN-proteins CYR61 and WISP3 are valuable for the musculoskeletal system. This and previous studies revealed the role of CYR61 for osteogenesis and angiogenesis of tissue engineered applications. WISP3 is responsible for development, protection and maintenance of cartilage. Therefore further studies with the proteins in the musculoskeletal system are of high relevance.}, subject = {Endothel}, language = {en} } @article{SteinertWeissenbergerKunzetal.2012, author = {Steinert, Andre F. and Weissenberger, Manuel and Kunz, Manuela and Gilbert, Fabian and Ghivizzani, Steven C. and Goebel, Sascha and Jakob, Franz and N{\"o}th, Ulrich and Rudert, Maximilian}, title = {Indian hedgehog gene transfer is a chondrogenic inducer of human mesenchymal stem cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75425}, year = {2012}, abstract = {Introduction: To date, no single most-appropriate factor or delivery method has been identified for the purpose of mesenchymal stem cell (MSC)-based treatment of cartilage injury. Therefore, in this study we tested whether gene delivery of the growth factor Indian hedgehog (IHH) was able to induce chondrogenesis in human primary MSCs, and whether it was possible by such an approach to modulate the appearance of chondrogenic hypertrophy in pellet cultures in vitro. Methods: First-generation adenoviral vectors encoding the cDNA of the human IHH gene were created by cre-lox recombination and used alone or in combination with adenoviral vectors, bone morphogenetic protein-2 (Ad.BMP- 2), or transforming growth factor beta-1 (Ad.TGF-b1) to transduce human bone-marrow derived MSCs at 5 × 102 infectious particles/cell. Thereafter, 3 × 105 cells were seeded into aggregates and cultured for 3 weeks in serumfree medium, with untransduced or marker gene transduced cultures as controls. Transgene expressions were determined by ELISA, and aggregates were analysed histologically, immunohistochemically, biochemically and by RT-PCR for chondrogenesis and hypertrophy. Results: IHH, TGF-b1 and BMP-2 genes were equipotent inducers of chondrogenesis in primary MSCs, as evidenced by strong staining for proteoglycans, collagen type II, increased levels of glycosaminoglycan synthesis, and expression of mRNAs associated with chondrogenesis. IHH-modified aggregates, alone or in combination, also showed a tendency to progress towards hypertrophy, as judged by the expression of alkaline phosphatase and stainings for collagen type X and Annexin 5. Conclusion: As this study provides evidence for chondrogenic induction of MSC aggregates in vitro via IHH gene delivery, this technology may be efficiently employed for generating cartilaginous repair tissues in vivo.}, subject = {Medizin}, language = {en} } @article{HolzapfelProdingerPilgeetal.2013, author = {Holzapfel, Boris Michael and Prodinger, Peter M. and Pilge, Hakan and Banke, Ingo J. and B{\"u}rklein, Dominik and Miethke, Thomas and Gradinger, Reiner}, title = {Acute Osteomyelitis of the Humerus mimicking Malignancy: Streptococcus pneumoniae as Exceptional Pathogen in an Immunocompetent Adult}, series = {BMC Infectious Diseases}, journal = {BMC Infectious Diseases}, doi = {10.1186/1471-2334-13-266}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-95790}, year = {2013}, abstract = {Background Chronic osteomyelitis due to direct bone trauma or vascular insufficiency is a frequent problem in orthopaedic surgery. In contrast, acute haematogenous osteomyelitis represents a rare entity that almost exclusively affects prepubescent children or immunodeficient adults. Case Presentation In this article, we report the case of acute pneumococcal osteomyelitis of the humerus in an immunocompetent and otherwise healthy 44-year-old male patient presenting with minor inflammation signs and misleading clinical features. Conclusions The diagnosis had to be confirmed by open biopsy which allowed the initiation of a targeted therapy. A case of pneumococcal osteomyelitis of a long bone, lacking predisposing factors or trauma, is unique in adults and has not been reported previously.}, language = {en} } @article{NedopilRaabRudert2013, author = {Nedopil, Alexander and Raab, Peter and Rudert, Maximilian}, title = {Desmoplastic Fibroma: A Case Report with Three Years of Clinical and Radiographic Observation and Review of the Literature}, series = {Open Orthopaedics Journal}, journal = {Open Orthopaedics Journal}, doi = {10.2174/1874325001307010040}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96123}, year = {2013}, abstract = {Background: Desmoplastic fibroma (DF) is an extremely rare locally aggressive bone tumor with an incidence of 0.11\% of all primary bone tumors. The typical clinical presentation is pain and swelling above the affected area. The most common sites of involvement are the mandible and the metaphysis of long bones. Histologically and biologically, desmoplastic fibroma mimics extra-abdominal desmoid tumor of soft tissue. Case Presentation and Literature Review: A case of a 27-year old man with DF in the ilium, including the clinical, radiological and histological findings over a 4-year period is presented here. CT scans performed in 3-year intervals prior to surgical intervention were compared with respect to tumor extension and cortical breakthrough. The patient was treated with curettage and grafting based on anatomical considerations. Follow-up CT scans over 18-months are also documented here. Additionally, a review and analysis of 271 cases including the presented case with particular emphasis on imaging patterns in MRI and CT as well as treatment modalities and outcomes are presented. Conclusion: In patients with desmoplastic fibroma, CT is the preferred imaging technique for both the diagnosis of intraosseus tumor extension and assessment of cortical involvement, whereas MRI is favored for the assessment of extraosseus tumor growth and preoperative planning. While tumor resection remains the preferred treatment for DF, curettage and grafting prove to be an acceptable alternative treatment modality with close follow-up when resection is not possible. Curettage and grafting have been shown to provide good clinical results and are associated with long recurrence free intervals.}, language = {en} } @article{Rudert2022, author = {Rudert, Maximilian}, title = {Taking the next step in personalised orthopaedic implantation}, series = {Journal of Personalized Medicine}, volume = {12}, journal = {Journal of Personalized Medicine}, number = {3}, issn = {2075-4426}, doi = {10.3390/jpm12030365}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-262089}, year = {2022}, abstract = {No abstract available}, language = {en} } @article{HochleitnerJuengstBrownetal.2015, author = {Hochleitner, Gernot and J{\"u}ngst, Tomasz and Brown, Toby D and Hahn, Kathrin and Moseke, Claus and Jakob, Franz and Dalton, Paul D and Groll, J{\"u}rgen}, title = {Additive manufacturing of scaffolds with sub-micron filaments via melt electrospinning writing}, series = {Biofabrication}, volume = {7}, journal = {Biofabrication}, number = {3}, doi = {10.1088/1758-5090/7/3/035002}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-254053}, year = {2015}, abstract = {The aim of this study was to explore the lower resolution limits of an electrohydrodynamic process combined with direct writing technology of polymer melts. Termed melt electrospinning writing, filaments are deposited layer-by-layer to produce discrete three-dimensional scaffolds for in vitro research. Through optimization of the parameters (flow rate, spinneret diameter, voltage, collector distance) for poly-ϵ-caprolactone, we could direct-write coherent scaffolds with ultrafine filaments, the smallest being 817 ± 165 nm. These low diameter filaments were deposited to form box-structures with a periodicity of 100.6 ± 5.1 μm and a height of 80 μm (50 stacked filaments; 100 overlap at intersections). We also observed oriented crystalline regions within such ultrafine filaments after annealing at 55 °C. The scaffolds were printed upon NCO-sP(EO-stat-PO)-coated glass slide surfaces and withstood frequent liquid exchanges with negligible scaffold detachment for at least 10 days in vitro.}, language = {en} } @misc{Seefried2023, author = {Seefried, Lothar}, title = {Supplement: Impaired Physical Performance in X-linked Hypophosphatemia is not caused by depleted muscular phosphate stores}, series = {Journal of Clinical Endocrinology \& Metabolism}, journal = {Journal of Clinical Endocrinology \& Metabolism}, doi = {10.25972/OPUS-30364}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-303647}, year = {2023}, abstract = {Supplemental Data to "Impaired Physical Performance in X-linked Hypophosphatemia is not caused by depleted muscular phosphate stores"}, language = {en} } @article{AchenbachHuppertzZemanetal.2022, author = {Achenbach, Leonard and Huppertz, Gunnar and Zeman, Florian and Weber, Johannes and Luig, Patrick and Rudert, Maximilian and Krutsch, Werner}, title = {Multicomponent stretching and rubber band strengthening exercises do not reduce overuse shoulder injuries: a cluster randomised controlled trial with 579 handball athletes}, series = {BMJ Open Sport \& Exercise Medicine}, volume = {8}, journal = {BMJ Open Sport \& Exercise Medicine}, number = {1}, issn = {2055-7647}, doi = {10.1136/bmjsem-2021-001270}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300770}, year = {2022}, abstract = {Objectives Handball is associated with a high risk of overuse shoulder injury. This study investigated if an injury prevention programme effectively reduces overuse injury to the throwing shoulder of handball athletes. Methods 61 men's and women's handball teams (u-19 and senior athletes) were cluster-randomised into an intervention and a control group in the 2019-2020 season. Players of the intervention group regularly carried out an injury prevention programme. Both groups documented overuse shoulder injuries via an online questionnaire every second week. The primary endpoint was the prevalence of overuse injury to the throwing shoulder. Secondary endpoints were the influence of compliance on the primary endpoint and intensity of overuse shoulder symptoms measured by a shortened, handball-specific Western Ontario Shoulder Index (WOSI). Results 31 teams (295 players) in the intervention group and 30 teams (284 players) in the control group were included for analyses. The overall questionnaire response rate was 61\%. The average prevalence of overuse shoulder injury did not significantly differ between the intervention group (n=109, 38.4\% (95\% CI 32.9\% to 44.2\%)) and the control group (n=106, 35.9\% (95\% CI 30.7\% to 41.6\%), p=0.542). Compliance with the intervention programme did not significantly affect overuse shoulder injury (p=0.893). Using generalised estimating equations for WOSI, the estimated mean for the intervention group was 44.6 points (95\% CI 42.0 to 47.1) and 47.6 points for the control group (95\% CI 44.9 to 50.3, p=0.111). Conclusions A multicomponent exercise programme using rubber bands and stretching did not significantly reduce the prevalence or symptoms of overuse throwing shoulder injury in handball athletes of both sexes. Randomised controlled study; level of evidence I.}, language = {en} } @article{EbertBenischKrugetal.2015, author = {Ebert, Regina and Benisch, Peggy and Krug, Melanie and Zeck, Sabine and Meißner-Weigl, Jutta and Steinert, Andre and Rauner, Martina and Hofbauer, Lorenz and Jakob, Franz}, title = {Acute phase serum amyloid A induces proinflammatory cytokines and mineralization via toll-like receptor 4 in mesenchymal stem cells}, series = {Stem Cell Research}, volume = {15}, journal = {Stem Cell Research}, doi = {10.1016/j.scr.2015.06.008}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-148491}, pages = {231-239}, year = {2015}, abstract = {The role of serum amyloid A (SAA) proteins, which are ligands for toll-like receptors, was analyzed in human bone marrow-derived mesenchymal stem cells (hMSCs) and their osteogenic offspring with a focus on senescence, differentiation andmineralization. In vitro aged hMSC developed a senescence-associated secretory phenotype (SASP), resulting in enhanced SAA1/2, TLR2/4 and proinflammatory cytokine (IL6, IL8, IL1\(\beta\), CXCL1, CXCL2) expression before entering replicative senescence. Recombinant human SAA1 (rhSAA1) induced SASP-related genes and proteins in MSC, which could be abolished by cotreatment with the TLR4-inhibitor CLI-095. The same pattern of SASP-resembling genes was stimulated upon induction of osteogenic differentiation, which is accompanied by autocrine SAA1/2 expression. In this context additional rhSAA1 enhanced the SASP-like phenotype, accelerated the proinflammatory phase of osteogenic differentiation and enhanced mineralization. Autocrine/paracrine and rhSAA1 via TLR4 stimulate a proinflammatory phenotype that is both part of the early phase of osteogenic differentiation and the development of senescence. This signaling cascade is tightly involved in bone formation and mineralization, but may also propagate pathological extraosseous calcification conditions such as calcifying inflammation and atherosclerosis.}, language = {en} } @article{SzymskiAchenbachSiebentrittetal.2021, author = {Szymski, Dominik and Achenbach, Leonard and Siebentritt, Martin and Simoni, Karola and Kuner, Norbert and Pfeifer, Christian and Krutsch, Werner and Alt, Volker and Meffert, Rainer and Fehske, Kai}, title = {Injury epidemiology of 626 athletes in surfing, wind surfing and kite surfing}, series = {Open Access Journal of Sports Medicine}, volume = {12}, journal = {Open Access Journal of Sports Medicine}, doi = {10.2147/OAJSM.S316642}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261545}, pages = {99-107}, year = {2021}, abstract = {Introduction/Background Surfing, wind surfing and kite surfing enjoy a growing popularity with a large number of athletes worldwide. The aim of this study was to identify and compare the injury profiles and compare the injury profiles of these three extreme water sports. Materials and Methods These data for this retrospective cohort study were collected through an online standardised questionnaire during the 2017-18 season. The questionnaire included questions about anthropometry, skill level, injury diagnosis, injury mechanism, environmental conditions and training regimes. Results The 626 athletes included reported 2584 injuries. On average, each athlete sustained 4.12 injuries during the season. The most frequent injury location was in the lower extremity, in particular the foot, with 49 (16.4\%) injuries in surfing, 344 (18.3\%) in wind surfing and 79 (19.7\%) in kite surfing. Surfing demonstrated a particularly high rate of head injuries (n = 37; 12.4\%). Other frequent injury types were skin lesions (up to 42.1\%) and contusions (up to 40.5\%). The most common injury across all surfing sports was skin lesions of the foot (wind surfing: 11.7\%; kite surfing: 13.2\%; surfing: 12.7\%). In surfing, skin lesions of the head were frequently observed (n = 24; 8.0\%). In surfing, a 'too large wave' (n = 18; 24.7\%) was main cause of the injury, while in wind surfing (n = 189; 34.5\%) and kite surfing (n = 65; 36.7\%) 'own incompetence' led to the most injuries. Conclusion This unique study compares injury epidemiology and mechanism in the three most popular surfing sports: wind surfing, kite surfing and surfing. Overall, injuries were sustained mainly in the lower extremity, while surfing also demonstrated a high rate of head injuries.}, language = {en} } @article{KaltdorfBreitenbachKarletal.2023, author = {Kaltdorf, Martin and Breitenbach, Tim and Karl, Stefan and Fuchs, Maximilian and Kessie, David Komla and Psota, Eric and Prelog, Martina and Sarukhanyan, Edita and Ebert, Regina and Jakob, Franz and Dandekar, Gudrun and Naseem, Muhammad and Liang, Chunguang and Dandekar, Thomas}, title = {Software JimenaE allows efficient dynamic simulations of Boolean networks, centrality and system state analysis}, series = {Scientific Reports}, volume = {13}, journal = {Scientific Reports}, doi = {10.1038/s41598-022-27098-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313303}, year = {2023}, abstract = {The signal modelling framework JimenaE simulates dynamically Boolean networks. In contrast to SQUAD, there is systematic and not just heuristic calculation of all system states. These specific features are not present in CellNetAnalyzer and BoolNet. JimenaE is an expert extension of Jimena, with new optimized code, network conversion into different formats, rapid convergence both for system state calculation as well as for all three network centralities. It allows higher accuracy in determining network states and allows to dissect networks and identification of network control type and amount for each protein with high accuracy. Biological examples demonstrate this: (i) High plasticity of mesenchymal stromal cells for differentiation into chondrocytes, osteoblasts and adipocytes and differentiation-specific network control focusses on wnt-, TGF-beta and PPAR-gamma signaling. JimenaE allows to study individual proteins, removal or adding interactions (or autocrine loops) and accurately quantifies effects as well as number of system states. (ii) Dynamical modelling of cell-cell interactions of plant Arapidopsis thaliana against Pseudomonas syringae DC3000: We analyze for the first time the pathogen perspective and its interaction with the host. We next provide a detailed analysis on how plant hormonal regulation stimulates specific proteins and who and which protein has which type and amount of network control including a detailed heatmap of the A.thaliana response distinguishing between two states of the immune response. (iii) In an immune response network of dendritic cells confronted with Aspergillus fumigatus, JimenaE calculates now accurately the specific values for centralities and protein-specific network control including chemokine and pattern recognition receptors.}, language = {en} } @article{WeissenbergerWagenbrennerSchoteetal.2022, author = {Weißenberger, Manuel and Wagenbrenner, Mike and Schote, Fritz and Horas, Konstantin and Sch{\"a}fer, Thomas and Rudert, Maximilian and Barthel, Thomas and Heinz, Tizian and Reppenhagen, Stephan}, title = {The 3-triangle method preserves the posterior tibial slope during high tibial valgus osteotomy: first preliminary data using a mathematical model}, series = {Journal of Experimental Orthopaedics}, volume = {9}, journal = {Journal of Experimental Orthopaedics}, issn = {2197-1153}, doi = {10.1186/s40634-022-00466-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300806}, year = {2022}, abstract = {Purpose Despite much improved preoperative planning techniques accurate intraoperative assessment of the high tibial valgus osteotomy (HTO) remains challenging and often results in coronal over- and under-corrections as well as unintended changes of the posterior tibial slope. Noyes et al. reported a novel method for accurate intraoperative coronal and sagittal alignment correction based on a three-dimensional mathematical model. This is the first study examining preliminary data via the proposed Noyes approach for accurate intraoperative coronal and sagittal alignment correction during HTO. Methods From 2016 to 2020 a total of 24 patients (27 knees) underwent HTO applying the proposed Noyes method (Noyes-Group). Radiographic data was analyzed retrospectively and matched to patients that underwent HTO using the conventional method, i.e., gradual medial opening using a bone spreader under fluoroscopic control (Conventional-Group). All operative procedures were performed by an experienced surgeon at a single orthopaedic university center. Results From the preoperative to the postoperative visit no statistically significant changes of the posterior tibial slope were noted in the Noyes-Group compared to a significant increase in the Conventional-Group (p = 0.01). Regarding the axial alignment no significant differences between both groups were observed pre- and postoperatively. The number of over- and under-corrections did not differ significantly between both groups. Linear regression analysis showed a significant correlation of the postoperative medial proximal tibial angle (MPTA) with the position of the weightbearing line on the tibial plateau. Conclusion The 3-triangle method by Noyes seems to be a promising approach for preservation of the posterior tibial slope during HTO.}, language = {en} } @article{JessbergerHoeggerGenestetal.2017, author = {Jessberger, Steffen and H{\"o}gger, Petra and Genest, Franca and Salter, Donald M. and Seefried, Lothar}, title = {Cellular pharmacodynamic effects of Pycnogenol\(^{®}\) in patients with severe osteoarthritis: a randomized controlled pilot study}, series = {BMC Complementary and Alternative Medicine}, volume = {17}, journal = {BMC Complementary and Alternative Medicine}, number = {537}, doi = {10.1186/s12906-017-2044-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-159532}, year = {2017}, abstract = {Background: The standardized maritime pine bark extract (Pycnogenol\(^{®}\)) has previously shown symptom alleviating effects in patients suffering from moderate forms of knee osteoarthritis (OA). The cellular mechanisms for this positive impact are so far unknown. The purpose of the present randomized pilot controlled study was to span the knowledge gap between the reported clinical effects of Pycnogenol\(^{®}\) and its in vivo mechanism of action in OA patients. Methods: Thirty three patients with severe OA scheduled for a knee arthroplasty either received 100 mg of Pycnogenol\(^{®}\) twice daily or no treatment (control group) three weeks before surgery. Cartilage, synovial fluid and serum samples were collected during surgical intervention. Relative gene expression of cartilage homeostasis markers were analyzed in the patients' chondrocytes. Inflammatory and cartilage metabolism mediators were investigated in serum and synovial fluid samples. Results: The oral intake of Pycnogenol\(^{®}\) downregulated the gene expression of various cartilage degradation markers in the patients' chondrocytes, the decrease of MMP3, MMP13 and the pro-inflammatory cytokine IL1B were statistically significant (p ≤ 0.05). Additionally, protein concentrations of ADAMTS-5 in serum were reduced significantly (p ≤ 0.05) after three weeks intake of the pine bark extract. Conclusions: This is the first report about positive cellular effects of a dietary supplement on key catabolic and inflammatory markers in patients with severe OA. The results provide a rational basis for understanding previously reported clinical effects of Pycnogenol\(^{®}\) on symptom scores of patients suffering from OA.}, language = {en} } @article{GenestLindstroemSchereretal.2021, author = {Genest, Franca and Lindstr{\"o}m, Sarah and Scherer, Sophia and Schneider, Michael and Seefried, Lothar}, title = {Feasibility of simple exercise interventions for men with osteoporosis - A prospective randomized controlled pilot study}, series = {Bone Reports}, volume = {15}, journal = {Bone Reports}, doi = {10.1016/j.bonr.2021.101099}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261434}, year = {2021}, abstract = {Background Aging is associated with progressive loss of musculoskeletal performance. Exercise interventions can improve physical function in the elderly but there is a paucity of comparative assessments in order to understand what specific goals can be achieved particularly with less demanding exercise interventions readily accessible for untrained men. Methods Prospective randomized, controlled, single center exploratory trial to compare four distinct exercise interventions, i.e. Resistance Training (RT), Whole Body Vibration Exercise (WBV), Qi Gong (QG) and wearing a Spinal orthosis (SO) for 6 months in men at risk for osteoporosis aged 65-90 years. Primary endpoint was change in isometric one repetition maximum force trunk strength for extension (TSE) and flexion (TSF) compared to baseline, secondary endpoints covered key parameters of geriatric functional assessment, including Handgrip Strength (HS), Chair-Rise-Test (CRT), Usual Gait Speed (UGS) and Timed-Up-and-Go (TUG). Results Altogether 47 men (mean age 77 ±6.1 years) were randomized to RT, (n = 11) WBV (n = 13), QG (n = 10) and SO(n = 13). RT, defined as reference exercise intervention, lead to significant improvements for TSE (p = 0.009) and TSF (p = 0.013) and was significantly superior in the between-group analysis for TSE (p = 0.038). Vibration exercise caused sign. Improvements in TSE (p = 0.014) and CRT (p = 0.005), the Spinal orthosis improved CRT (p = 0.003) and Gait Speed (p = 0.027), while the QG intervention did not attain any sig. Developments. Subgroup analyses revealed most pronounced musculoskeletal progress in vulnerable patients (age ≥ 80 years, pre-sarcopenia, multimorbidity ≥3chronic diseases). Irrespective of the type of exercise, participants ≥80 years experienced significant gains in TSE (p = 0.029) and CRT (p = 0.017). Presarcopenic subjects (Skeletal muscle Index (SMI) ≤10.75 kg/m2) improved in TSE (p = 0.003), CRT (p = 0.001) and UGS (p = 0.016). Multimorbid participants achieved sig. Gains in TSE (p < 0.001), TSF (p = 0.002), UGS (p = 0.036) and HS (p = 0.046). Conclusions In this exploratory trial we found that simple exercise interventions are feasible in elderly men eliciting specific benefits, i.e. improvements are attained in those tasks addressed with the respective exercise modality. While targeted resistance training is superior in increasing TSE, alternative simple exercise interventions also appear to elicit beneficial effects, even in vulnerable patients, i.e. those with low muscle mass, above 80 years of age or multimorbidity.}, language = {en} } @article{EbertWeissenbergerBraunetal.2022, author = {Ebert, Regina and Weissenberger, Manuel and Braun, Clemens and Wagenbrenner, Mike and Herrmann, Marietta and M{\"u}ller-Deubert, Sigrid and Krug, Melanie and Jakob, Franz and Rudert, Maximilian}, title = {Impaired regenerative capacity and senescence-associated secretory phenotype in mesenchymal stromal cells from samples of patients with aseptic joint arthroplasty loosening}, series = {Journal of Orthopaedic Research}, volume = {40}, journal = {Journal of Orthopaedic Research}, number = {2}, doi = {10.1002/jor.25041}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-238963}, pages = {513 -- 523}, year = {2022}, abstract = {Aseptic loosening of total hip and knee joint replacements is the most common indication for revision surgery after primary hip and knee arthroplasty. Research suggests that exposure and uptake of wear by mesenchymal stromal cells (MSC) and macrophages results in the secretion of proinflammatory cytokines and local osteolysis, but also impaired cell viability and regenerative capacity of MSC. Therefore, this in vitro study compared the regenerative and differentiation capacity of MSC derived from patients undergoing primary total hip arthroplasty (MSCprim) to MSC derived from patients undergoing revision surgery after aseptic loosening of total hip and knee joint implants (MSCrev). Regenerative capacity was examined by measuring the cumulative population doubling (CPD) in addition to the number of passages until cells stopped proliferating. Osteogenesis and adipogenesis in monolayer cultures were assessed using histological stainings. Furthermore, RT-PCR was performed to evaluate the relative expression of osteogenic and adipogenic marker genes as well as the expression of markers for a senescence-associated secretory phenotype (SASP). MSCrev possessed a limited regenerative capacity in comparison to MSCprim. Interestingly, MSCrev also showed an impaired osteogenic and adipogenic differentiation capacity compared to MSCprim and displayed a SASP early after isolation. Whether this is the cause or the consequence of the aseptic loosening of total joint implants remains unclear. Future research should focus on the identification of specific cell markers on MSCprim, which may influence complication rates such as aseptic loosening of total joint arthroplasty to further individualize and optimize total joint arthroplasty.}, language = {en} } @article{SappeyMarinierHowellNedopiletal.2022, author = {Sappey-Marinier, Elliot and Howell, Stephen M. and Nedopil, Alexander J. and Hull, Maury L.}, title = {The trochlear groove of a femoral component designed for kinematic alignment is lateral to the quadriceps line of force and better laterally covers the anterior femoral resection than a mechanical alignment design}, series = {Journal of Personalized Medicine}, volume = {12}, journal = {Journal of Personalized Medicine}, number = {10}, issn = {2075-4426}, doi = {10.3390/jpm12101724}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-290482}, year = {2022}, abstract = {Background: A concern about kinematically aligned (KA) total knee arthroplasty (TKA) is that it relies on femoral components designed for mechanical alignment (MAd-FC) that could affect patellar tracking, in part, because of a trochlear groove orientation that is typically 6° from vertical. KA sets the femoral component coincident to the patient's pre-arthritic distal and posterior femoral joint lines and restores the Q-angle, which varies widely. Relative to KA and the native knee, aligning the femoral component with MA changes most distal joint lines and Q-angles, and rotates the posterior joint line externally laterally covering the anterior femoral resection. Whether switching from a MAd- to a KAd-FC with a wider trochlear groove orientation of 20.5° from vertical results in radiographic measures known to promote patellar tracking is unknown. The primary aim was to determine whether a KAd-FC sets the trochlear groove lateral to the quadriceps line of force (QLF), better laterally covers the anterior femoral resection, and reduces lateral patella tilt relative to a MAd-FC. The secondary objective was to determine at six weeks whether the KAd-FC resulted in a higher complication rate, less knee extension and flexion, and lower clinical outcomes. Methods: Between April 2019 and July 2022, two surgeons performed sequential bilateral unrestricted caliper-verified KA TKA with manual instruments on thirty-six patients with a KAd- and MAd-FC in opposite knees. An observer measured the angle between a line best-fit to the deepest valley of the trochlea and a line representing the QLF that indicated the patient's Q-angle. When the trochlear groove was lateral or medial relative to the QLF, the angle is denoted + or -, and the femoral component included or excluded the patient's Q-angle, respectively. Software measured the lateral undercoverage of the anterior femoral resection on a Computed Tomography (CT) scan, and the patella tilt angle (PTA) on a skyline radiograph. Complications, knee extension and flexion measurements, Oxford Knee Score, KOOS Jr, and Forgotten Joint Score were recorded pre- and post-operatively (at 6 weeks). A paired Student's T-test determined the difference between the KA TKAs with a KAd-FC and MAd-FC with a significance set at p < 0.05. Results: The final analysis included thirty-five patients. The 20.5° trochlear groove of the KAd-FC was lateral to the QLF in 100\% (15 ± 3°) of TKAs, which was greater than the 69\% (1 ± 3°) lateral to the QLF with the 6° trochlear groove of the MAd-FC (p < 0.001). The KAd-FC's 2 ± 1.9 mm lateral undercoverage of the anterior femoral resection was less than the 4.4 ± 1.5 mm for the MAd-FC (p < 0.001). The PTA, complication rate, knee extension and flexion, and clinical outcome measures did not differ between component designs. Conclusions: The KA TKA with a KAd-FC resulted in a trochlear groove lateral to the QLF that included the Q-angle in all patients, and negligible lateral undercoverage of the anterior femoral resection. These newly described radiographic parameters could be helpful when investigating femoral components designed for KA with the intent of promoting patellofemoral kinematics.}, language = {en} } @article{EidmannEisertRudertetal.2022, author = {Eidmann, Annette and Eisert, Marius and Rudert, Maximilian and Stratos, Ioannis}, title = {Influence of Vitamin D and C on bone marrow edema syndrome — A scoping review of the literature}, series = {Journal of Clinical Medicine}, volume = {11}, journal = {Journal of Clinical Medicine}, number = {22}, issn = {2077-0383}, doi = {10.3390/jcm11226820}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297356}, year = {2022}, abstract = {Bone marrow edema syndrome (BMES) is a rare disease with a largely unknown etiology. The aim of this scoping review is to systematically evaluate and combine the available evidence about vitamin D and C and BMES. The analysis of the manuscripts was based on country of origin, number of patients, gender, study type, epidemiology, localization, bone mineral density measurements, vitamin status and therapy. Sixty studies were included. The overall number of patients was 823 with a male-to-female ratio of 1.55:1 and a mean age of 40.9 years. Studies were very heterogeneous and of diverging scientific scope with a weak level of evidence. The hip was the most affected joint, followed by the foot and ankle and the knee; 18.3\% of patients suffered from multifocal BMES. Sixteen studies reported on vitamin D levels, resulting in a high prevalence of vitamin D deficiency (47\%) and insufficiency (17.9\%) among BMES patients. Three BME manuscripts were associated with vitamin C deficiency. Current therapeutic interventions include conservative measures (mainly unloading), various osteoactive drugs and iloprost. In summary, data about BMES in association with vitamin status is limited. A causal relationship between vitamin D or vitamin C status, osteopenia, and BMES cannot be determined from the existing literature.}, language = {en} } @book{Wang2008, author = {Wang, Wen}, title = {Validation of shRNA clones for gene silencing in 293FT cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-25955}, publisher = {Universit{\"a}t W{\"u}rzburg}, year = {2008}, abstract = {...}, subject = {shRNA}, language = {en} } @article{RakKlannHeinzetal.2023, author = {Rak, Dominik and Klann, Lukas and Heinz, Tizian and Anderson, Philip and Stratos, Ioannis and Nedopil, Alexander J. and Rudert, Maximilian}, title = {Influence of mechanical alignment on functional knee phenotypes and clinical outcomes in primary TKA: a 1-year prospective analysis}, series = {Journal of Personalized Medicine}, volume = {13}, journal = {Journal of Personalized Medicine}, number = {5}, issn = {2075-4426}, doi = {10.3390/jpm13050778}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313646}, year = {2023}, abstract = {In total knee arthroplasty (TKA), functional knee phenotypes are of interest regarding surgical alignment strategies. Functional knee phenotypes were introduced in 2019 and consist of limb, femoral, and tibial phenotypes. The hypothesis of this study was that mechanically aligned (MA) TKA changes preoperative functional phenotypes, which decreases the 1-year Forgotten Joint (FJS) and Oxford Knee Score (OKS) and increases the 1-year WOMAC. All patients included in this study had end-stage osteoarthritis and were treated with a primary MA TKA, which was supervised by four academic knee arthroplasty specialists. To determine the limb, femoral, and tibial phenotype, a long-leg radiograph (LLR) was imaged preoperatively and two to three days after TKA. FJS, OKS, and WOMAC were obtained 1 year after TKA. Patients were categorized using the change in functional limb, femoral, and tibial phenotype measured on LLR, and the scores were compared between the different categories. A complete dataset of preoperative and postoperative scores and radiographic images could be obtained for 59 patients. 42\% of these patients had a change of limb phenotype, 41\% a change of femoral phenotype, and 24\% a change of tibial phenotype of more than ±1 relative to the preoperative phenotype. Patients with more than ±1 change of limb phenotype had significantly lower median FJS (27 points) and OKS (31 points) and higher WOMAC scores (30 points) relative to the 59-, 41-, and 4-point scores of those with a 0 ± 1 change (p < 0.0001 to 0.0048). Patients with a more than ±1 change of femoral phenotype had significantly lower median FJS (28 points) and OKS (32 points) and higher WOMAC scores (24 points) relative to the 69-, 40-, and 8-point scores of those with a 0 ± 1 change (p < 0.0001). A change in tibial phenotype had no effect on the FJS, OKS, and WOMAC scores. Surgeons performing MA TKA could consider limiting coronal alignment corrections of the limb and femoral joint line to within one phenotype to reduce the risk of low patient-reported satisfaction and function at 1-year.}, language = {en} } @article{WeberBeckKlugetal.2023, author = {Weber, Patrick and Beck, Melina and Klug, Michael and Klug, Andreas and Klug, Alexander and Glowalla, Claudio and Gollwitzer, Hans}, title = {Survival of patient-specific unicondylar knee replacement}, series = {Journal of Personalized Medicine}, volume = {13}, journal = {Journal of Personalized Medicine}, number = {4}, issn = {2075-4426}, doi = {10.3390/jpm13040665}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-313650}, year = {2023}, abstract = {Unicompartmental knee arthroplasty (UKA) in isolated medial or lateral osteoarthritis leads to good clinical results. However, revision rates are higher in comparison to total knee arthroplasty (TKA). One reason is suboptimal fitting of conventional off-the-shelf prostheses, and major overhang of the tibial component over the bone has been reported in up to 20\% of cases. In this retrospective study, a total of 537 patient-specific UKAs (507 medial prostheses and 30 lateral prostheses) that had been implanted in 3 centers over a period of 10 years were analyzed for survival, with a minimal follow-up of 1 year (range 12 to 129 months). Furthermore, fitting of the UKAs was analyzed on postoperative X-rays, and tibial overhang was quantified. A total of 512 prostheses were available for follow-up (95.3\%). Overall survival rate (medial and lateral) of the prostheses after 5 years was 96\%. The 30 lateral UKAs showed a survival rate of 100\% at 5 years. The tibial overhang of the prosthesis was smaller than 1 mm in 99\% of cases. In comparison to the reported results in the literature, our data suggest that the patient-specific implant design used in this study is associated with an excellent midterm survival rate, particularly in the lateral knee compartment, and confirms excellent fitting.}, language = {en} } @article{TrivanovicVolkmannStoeckletal.2023, author = {Trivanovic, Drenka and Volkmann, Noah and Stoeckl, Magdalena and Tertel, Tobias and Rudert, Maximilian and Giebel, Bernd and Herrmann, Marietta}, title = {Enhancement of immunosuppressive activity of mesenchymal stromal cells by platelet-derived factors is accompanied by apoptotic priming}, series = {Stem Cell Reviews and Reports}, volume = {19}, journal = {Stem Cell Reviews and Reports}, number = {3}, doi = {10.1007/s12015-022-10471-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324669}, pages = {713-733}, year = {2023}, abstract = {The pro-inflammatory phase of bone healing, initiated by platelet activation and eventually hematoma formation, impacts bone marrow mesenchymal stromal cells (MSCs) in unknown ways. Here, we created platelet-rich plasma (PRP) hydrogels to study how platelet-derived factors modulate functional properties of encapsulated MSCs in comparison to a non-inflammatory fibrin (FBR) hydrogel environment. MSCs were isolated from human bone marrow, while PRP was collected from pooled apheresis thrombocyte concentrates and used for hydrogel preparation. After their encapsulation in hydrogels for 72 h, retrieved MSCs were analyzed for immunomodulatory activities, apoptosis, stem cell properties, senescence, CD9\(^+\), CD63\(^+\) and CD81\(^+\) extracellular vesicle (EV) release, and metabolism-related changes. PRP-hydrogels stimulated immunosuppressive functions of MSCs, along with their upregulated susceptibility to cell death in communication with PBMCs and augmented caspase 3/7 activity. We found impaired clonal growth and cell cycle progression, and more pronounced β-galactosidase activity as well as accumulation of LC3-II-positive vacuoles in PRP-MSCs. Stimuli derived from PRP-hydrogels upregulated AKT and reduced mTOR phosphorylation in MSCs, which suggests an initiation of survival-related processes. Our results showed that PRP-hydrogels might represent a metabolically stressful environment, inducing acidification of MSCs, reducing polarization of the mitochondrial membrane and increasing lipid accumulation. These features were not detected in FBR-MSCs, which showed reduced CD63\(^+\) and CD81\(^+\) EV production and maintained clonogenicity. Our data revealed that PRP-derived hematoma components cause metabolic adaptation of MSCs followed by increased immune regulatory functions. For the first time, we showed that PRP stimuli represent a survival challenge and "apoptotic priming" that are detrimental for stem cell-like growth of MSCs and important for their therapeutic consideration.}, language = {en} } @article{ScorcellettiKaraZangeetal.2022, author = {Scorcelletti, Matteo and Kara, Serhan and Zange, Jochen and Jordan, Jens and Semler, Oliver and Sch{\"o}nau, Eckhard and Rittweger, J{\"o}rn and Ireland, Alex and Seefried, Lothar}, title = {Lower limb bone geometry in adult individuals with X-linked hypophosphatemia: an observational study}, series = {Osteoporosis International}, volume = {33}, journal = {Osteoporosis International}, number = {7}, doi = {10.1007/s00198-022-06385-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324655}, pages = {1601-1611}, year = {2022}, abstract = {Summary We assessed lower-limb geometry in adults with X-linked hypophosphatemia (XLH) and controls. We found large differences in multiple measures including femoral and tibial torsion, bowing and cross-sectional area and acetabular version and coverage which may contribute to clinical problems such as osteoarthritis, fractures and altered gait common in XLH. Purpose Individuals with X-linked hypophosphatemia (XLH) are at risk of lower-limb deformities and early onset of osteoarthritis. These two factors may be linked, as altered biomechanics is a risk factor for osteoarthritis. This exploratory evaluation aims at providing clues and concepts for this association to facilitate future larger-scale and longitudinal studies on that aspect. Methods For this observational study, 13 patients with XLH, aged 18-65 years (6 female), were compared with sex-, age- and weight-matched healthy individuals at a single German research centre. Femoral and hip joint geometry, including femoral and tibial torsion and femoral and tibial shaft bowing, bone cross-sectional area (CSA) and acetabular version and coverage were measured from magnetic resonance imaging (MRI) scans. Results Total femoral torsion was 29° lower in individuals with XLH than in controls (p < 0.001), mainly resulting from lower intertrochanteric torsion (ITT) (p < 0.001). Femoral lateral and frontal bowing, tibial frontal bowing, mechanical axis, femoral mechanical-anatomical angle, acetabular version and acetabular coverage were all greater and tibial torsion lower in individuals with XLH as compared to controls (all p < 0.05). Greater femoral total and marrow cavity CSA, greater tibial marrow cavity CSA and lower cortical CSA were observed in XLH (all p < 0.05). Discussion We observed large differences in clinically relevant measures of tibia and particularly femur bone geometry in individuals with XLH compared to controls. These differences may plausibly contribute to clinical manifestations of XLH such as early-onset osteoarthritis, pseudofractures and altered gait and therefore should be considered when planning corrective surgeries.}, language = {en} } @article{HoertererBaumbachLemperleetal.2019, author = {H{\"o}rterer, Hubert and Baumbach, Sebastian Felix and Lemperle, Stefan and Altenberger, Sebastian and Gottschalk, Oliver and Mehlhorn, Alexander Tobias and R{\"o}ser, Anke and Walther, Markus}, title = {Clinical outcome and concomitant injuries in operatively treated fractures of the lateral process of the talus}, series = {BMC Musculoskeletal Disorders}, volume = {20}, journal = {BMC Musculoskeletal Disorders}, doi = {10.1186/s12891-019-2603-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-321207}, year = {2019}, abstract = {Background The aim of this study was to review the patient rated outcome (PROM) of surgically treated fractures to the lateral process of the talus (LPTF) and identify factors influencing the outcome. Methods Retrospective study with a current follow-up. Eligible were all patients treated surgically for a LPTF (n = 23) with a minimum follow-up of one year. Demographics, medical history, trauma mechanism, fracture characteristics, concomitant injuries, treatment details, complications, return to work and sports were assessed retrospectively. The current follow-up included the VAS FA, Karlsson Score, and SF-12. The primary outcome was the VAS FA. Secondary aim was the identification of parameters influencing the PROMs. Results 22 patients (96\% follow-up) with a mean age of 32 ± 9 (18 to 49) years were included. 73\% suffered a Hawkins Type 1, 23\% a Type 2, and one patient a Type 3 fracture. 82\% suffered concomitant injuries. 9\% suffered minor surgical side infections, 50\% developed symptomatic subtalar osteoarthritis. At final follow-up (44 ± 2 (12 to 97) months), the mean VAS FA Overall was 77 ± 21 (20 to 100), the Karlsson Score 72 ± 21 (34 to 97), and for the SF 12 the PCS 53 ± 8 (36 to 64) and the MCS 53 ± 7 (32 to 63). 50\% of patients returned to their previous level of sports. Hawkins Type 1 fractures resulted in better VAS FA Overall score than Type 2 fractures. Posttraumatic subtalar osteoarthritis was the independent factor associated to a poor patient rated outcome (VAS FA, Karlsson Score). Conclusion After a follow-up of over 3.5 years, surgically treated LPTF resulted in only moderate results. 50\% suffered posttraumatic symptomatic subtalar osteoarthritis, which was the primary independent parameter for a poor outcome following LPTF. Level of evidence Level III.}, language = {en} } @article{SteinertSchroederSefrinetal.2022, author = {Steinert, Andre F. and Schr{\"o}der, Lennart and Sefrin, Lukas and Janßen, Bj{\"o}rn and Arnholdt, J{\"o}rg and Rudert, Maximilian}, title = {The impact of total knee replacement with a customized cruciate-retaining implant design on patient-reported and functional outcomes}, series = {Journal of Personalized Medicine}, volume = {12}, journal = {Journal of Personalized Medicine}, number = {2}, issn = {2075-4426}, doi = {10.3390/jpm12020194}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-312746}, year = {2022}, abstract = {Purpose: To treat patients with tricompartimental knee osteoarthritis (OA), a customized cruciate-retaining total knee arthroplasty (CCR-TKA) system can be used, including both individualized instrumentation and implants. The objective of this monocentric cohort study was to analyze patient-reported and functional outcomes in a series of patients implanted with the second generation of this customized implant. Methods: At our arthroplasty center, we prospectively recruited a cohort of patients with tricompartmental gonarthrosis to be treated with total knee replacement (TKA) using a customized cruciate-retaining (CCR) implant design. Inclusion criteria for patients comprised the presence of intact posterior cruciate and collateral ligaments and a knee deformity that was restricted to <15° varus, valgus, or flexion contracture. Patients were assessed for their range of motion (ROM), Knee Society Score (KSS), Western Ontario and McMaster University osteoarthritis index (WOMAC), and short form (SF)-12 physical and mental scores, preoperatively, at 3 and 6 months, as well as at 1, 2, 3, and 5 years of follow-up (FU) postoperatively. Results: The average age of the patient population was 64 years (range: 40-81), the average BMI was 31 (range: 23-42), and in total, 28 female and 45 male patients were included. Implant survivorship was 97.5\% (one septic loosening) at an average follow-up of 2.5 years. The KSS knee and function scores improved significantly (p < 0.001) from, respectively, 41 and 53 at the pre-operative visit, to 92 and 86, respectively, at the 5-year post-operative time point. The SF-12 Physical and Mental scores significantly (p < 0.001) improved from the pre-operative values of 28 and 50, to 50 and 53 at the 5-year FU, respectively. Patients experienced significant improvements in their overall knee range of motion, from 106° at the preoperative visit to 122°, on average, 5 years postoperatively. The total WOMAC score significantly (p < 0.001) improved from 49.1 preoperatively to 11.4 postoperatively at 5-year FU. Conclusions: Although there was no comparison to other implants within this study, patients reported high overall satisfaction and improvement in functional outcomes within the first year from surgery, which continued over the following years. These mid-term results are excellent compared with those reported in the current literature. Comparative long-term studies with this device are needed. Level of evidence 3b (individual case-control study).}, language = {en} } @article{MagesShojaaKohletal.2021, author = {Mages, Michelle and Shojaa, Mahdieh and Kohl, Matthias and Stengel, Simon von and Becker, Clemens and Gosch, Markus and Jakob, Franz and Kerschan-Schindl, Katharina and Kladny, Bernd and Kl{\"o}ckner, Nicole and Lange, Uwe and Middeldorf, Stefan and Peters, Stefan and Schoene, Daniel and Sieber, Cornel C. and Tholen, Reina and Thomasius, Friederike E. and Uder, Michael and Kemmler, Wolfgang}, title = {Exercise effects on Bone Mineral Density in men}, series = {Nutrients}, volume = {13}, journal = {Nutrients}, number = {12}, issn = {2072-6643}, doi = {10.3390/nu13124244}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-250247}, year = {2021}, abstract = {In contrast to postmenopausal women, evidence for a favorable effect of exercise on Bone Mineral Density (BMD) is still limited for men. This might be due to the paucity of studies, but also to the great variety of participants and study characteristics that may dilute study results. The aim of the present systematic review and meta-analysis was to evaluate the effect of exercise on BMD changes with rational eligibility criteria. A comprehensive search of six electronic databases up to 15 March 2021 was conducted. Briefly, controlled trials ≥6 months that determined changes in areal BMD in men >18 years old, with no apparent diseases or pharmacological therapy that relevantly affect bone metabolism, were included. BMD changes (standardized mean differences: SMD) of the lumbar spine (LS) and femoral neck (FN) were considered as outcomes. Twelve studies with 16 exercise and 12 control groups were identified. The pooled estimate of random-effect analysis was SMD = 0.38, 95\%-CI: 0.14-0.61 and SMD = 0.25, 95\%-CI: 0.00-0.49, for LS and FN, respectively. Heterogeneity between the trials was low-moderate. Funnel plots and rank and regression correlation tests indicate evidence for small study publication bias for LS but not FN-BMD. Subgroup analyses that focus on study length, type of exercise and methodologic quality revealed no significant difference between each of the three categories. In summary, we provided further evidence for a low but significant effect of exercise on BMD in men. However, we are currently unable to give even rough exercise recommendations for male cohorts.}, language = {en} } @article{WeissenbergerHeinzRueckletal.2020, author = {Weissenberger, Manuel and Heinz, Tizian and Rueckl, Kilian and Rudert, Maximilian and Klug, Alexander and Hoffmann, Reinhard and Schmidt-Horloh{\´e}, Kay}, title = {No functional differences in anatomic reconstruction with one vs. two suture anchors after non-simultaneous bilateral distal biceps brachii tendon rupture: a case report and review of the literature}, series = {BMC Musculoskeletal Disorders}, volume = {21}, journal = {BMC Musculoskeletal Disorders}, doi = {10.1186/s12891-020-03304-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229266}, year = {2020}, abstract = {Background Surgical reattachment of the tendon is still the gold standard for ruptures of the distal biceps brachii tendon. Several fixation techniques have been described in the literature, with suture anchors being one of the most common fixation techniques. Currently, there is no data available on how many anchors are required for a safe and stable refixation. In this case report clinical data of a patient with non-simultaneous bilateral distal biceps tendon ruptures treated with a different number of suture anchors for each side (one vs. two) are demonstrated. Case presentation A 47-year-old factory worker suffered a rupture of the distal biceps tendon on both arms following two different occasions. The left side was fixed using a single suture anchor, while refixation on the right side was performed with two anchors. The patient was prospectively followed for one year. Functional outcome was assessed using the Andrews Carson Score (ACS), the Oxford Elbow Score (OES), and the Disabilities of Arm, Shoulder and Hand (DASH) Score after six, twelve, 24 and 48 weeks. Furthermore, an isokinetic strength measurement for flexion strength was performed after 24 and 48 weeks. After 48 weeks the patient presented with excellent functional outcome scores and no follow-up complications. During the follow-up period, no differences in the functional scores nor in the isokinetic flexion strength measurement could be detected. Furthermore, no radiological complications (like heterotopic ossifications) could be detected in the postoperative radiographs after one year. Conclusions Anatomic reattachment of the distal biceps tendon is a successful operative treatment option for distal biceps tendon ruptures. Suture anchor fixation remains one of the most common techniques, as it allows fast surgery and provides good results with respect to range of motion (ROM) and functional scoring according to the current literature. However, the number of anchors required for a stable fixation remains unclear. As indicated by our presented case, we hypothesize, that there are no significant differences between a one-point or a two-point fixation. In the presented case report, no intraindividual differences between the usage of one versus two suture anchors were evident in the short-term follow-up.}, language = {en} } @article{EidmannEwaldBoelchetal.2021, author = {Eidmann, Annette and Ewald, Andrea and Boelch, Sebastian P. and Rudert, Maximilian and Holzapfel, Boris M. and Stratos, Ioannis}, title = {In vitro evaluation of antibacterial efficacy of vancomycin-loaded suture tapes and cerclage wires}, series = {Journal of Materials Science: Materials in Medicine}, volume = {32}, journal = {Journal of Materials Science: Materials in Medicine}, number = {4}, doi = {10.1007/s10856-021-06513-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260089}, pages = {42}, year = {2021}, abstract = {Usage of implants containing antibiotic agents has been a common strategy to prevent implant related infections in orthopedic surgery. Unfortunately, most implants with microbial repellent properties are characterized by accessibility limitations during daily clinical practice. Aim of this in vitro study was to investigate whether suture tapes and cerclage wires, which were treated with vancomycin, show a sustainable antibacterial activity. For this purpose, we used 24 stainless steel wire cerclages and 24 ultra-high molecular weight polyethylene and polyester suture tape test bodies. The test bodies were incubated for 30 min. in 100 mg/ml vancomycin solution or equivalent volumes of 0.9\% NaCl. After measuring the initial solution uptake of the test bodies, antibacterial efficacy via agar diffusion test with Staphylococcus aureus and vancomycin elution tests were performed 1, 2, 3, and 6 days after incubation. Vancomycin-loaded tapes as well as vancomycin-loaded cerclage wires demonstrated increased bacterial growth inhibition when compared to NaCl-treated controls. Vancomycin-loaded tapes showed an additional twofold and eightfold increase of bacterial growth inhibition compared to vancomycin-loaded wires at day 1 and 2, respectively. Elution tests at day 1 revealed high levels of vancomycin concentration in vancomycin loaded tapes and wires. Additionally, the concentration in vancomycin loaded tapes was 14-fold higher when compared to vancomycin loaded wires. Incubating suture tapes and cerclage wires in vancomycin solution showed a good short-term antibacterial activity compared to controls. Considering the ease of vancomycin application on suture tapes or wires, our method could represent an attractive therapeutic strategy in biofilm prevention in orthopedic surgery.}, language = {en} } @article{GraserLiedtkeJakob2021, author = {Graser, Stephanie and Liedtke, Daniel and Jakob, Franz}, title = {TNAP as a new player in chronic inflammatory conditions and metabolism}, series = {International Journal of Molecular Sciences}, volume = {22}, journal = {International Journal of Molecular Sciences}, number = {2}, issn = {1422-0067}, doi = {10.3390/ijms22020919}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-258888}, year = {2021}, abstract = {This review summarizes important information on the ectoenzyme tissue-nonspecific alkaline phosphatase (TNAP) and gives a brief insight into the symptoms, diagnostics, and treatment of the rare disease Hypophosphatasia (HPP), which is resulting from mutations in the TNAP encoding ALPL gene. We emphasize the role of TNAP beyond its well-known contribution to mineralization processes. Therefore, above all, the impact of the enzyme on central molecular processes in the nervous system and on inflammation is presented here.}, language = {en} } @article{ArmbrusterKriegWeissenbergeretal.2017, author = {Armbruster, Nicole and Krieg, Jennifer and Weißenberger, Manuel and Scheller, Carsten and Steinert, Andre F.}, title = {Rescued Chondrogenesis of Mesenchymal Stem Cells under Interleukin 1 Challenge by Foamyviral Interleukin 1 Receptor Antagonist Gene Transfer}, series = {Frontiers in Pharmacology}, volume = {8}, journal = {Frontiers in Pharmacology}, number = {255}, doi = {10.3389/fphar.2017.00255}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170919}, year = {2017}, abstract = {Background: Mesenchymal stem cells (MSCs) and their chondrogenic differentiation have been extensively investigated in vitro as MSCs provide an attractive source besides chondrocytes for cartilage repair therapies. Here we established prototype foamyviral vectors (FVV) that are derived from apathogenic parent viruses and are characterized by a broad host range and a favorable integration pattern into the cellular genome. As the inflammatory cytokine interleukin 1 beta (IL1β) is frequently present in diseased joints, the protective effects of FVV expressing the human interleukin 1 receptor antagonist protein (IL1RA) were studied in an established in vitro model (aggregate culture system) of chondrogenesis in the presence of IL1β. Materials and Methods: We generated different recombinant FVVs encoding enhanced green fluorescent protein (EGFP) or IL1RA and examined their transduction efficiencies and transgene expression profiles using different cell lines and human primary MSCs derived from bone marrow-aspirates. Transgene expression was evaluated by fluorescence microscopy (EGFP), flow cytometry (EGFP), and ELISA (IL1RA). For evaluation of the functionality of the IL1RA transgene to block the inhibitory effects of IL1β on chondrogenesis of primary MSCs and an immortalized MSC cell line (TERT4 cells), the cells were maintained following transduction as aggregate cultures in standard chondrogenic media in the presence or absence of IL1β. After 3 weeks of culture, pellets were harvested and analyzed by histology and immunohistochemistry for chondrogenic phenotypes. Results: The different FVV efficiently transduced cell lines as well as primary MSCs, thereby reaching high transgene expression levels in 6-well plates with levels of around 100 ng/ml IL1RA. MSC aggregate cultures which were maintained in chondrogenic media without IL1β supplementation revealed a chondrogenic phenotype by means of strong positive staining for collagen type II and matrix proteoglycan (Alcian blue). Addition of IL1β was inhibitory to chondrogenesis in untreated control pellets. In contrast, foamyviral mediated IL1RA expression rescued the chondrogenesis in pellets cultured in the presence of IL1β. Transduced MSC pellets reached thereby very high IL1RA transgene expression levels with a peak of 1087 ng/ml after day 7, followed by a decrease to 194 ng/ml after day 21, while IL1RA concentrations of controls were permanently below 200 pg/ml. Conclusion: Our results indicate that FVV are capable of efficient gene transfer to MSCs, while reaching IL1RA transgene expression levels, that were able to efficiently block the impacts of IL1β in vitro. FVV merit further investigation as a means to study the potential as a gene transfer tool for MSC based therapies for cartilage repair.}, language = {en} } @article{MuellerDeubertSeefriedKrugetal.2017, author = {M{\"u}ller-Deubert, Sigrid and Seefried, Lothar and Krug, Melanie and Jakob, Franz and Ebert, Regina}, title = {Epidermal growth factor as a mechanosensitizer in human bone marrow stromal cells}, series = {Stem Cell Research}, volume = {24}, journal = {Stem Cell Research}, doi = {10.1016/j.scr.2017.08.012}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170247}, pages = {69-76}, year = {2017}, abstract = {Epidermal growth factors (EGFs) e.g. EGF, heparin-binding EGF and transforming growth factor alpha and their receptors e.g. EGFR and ErbB2 control proinflammatory signaling and modulate proliferation in bone marrow stromal cells (BMSC). Interleukin-6 and interleukin-8 are EGF targets and participate in the inflammatory phase of bone regeneration via non-canonical wnt signaling. BMSC differentiation is also influenced by mechanical strain-related activation of ERK1/2 and AP-1, but the role of EGFR signaling in mechanotransduction is unclear. We investigated the effects of EGFR signaling in telomerase-immortalized BMSC, transfected with a luciferase reporter, comprising a mechanoresponsive AP1 element, using ligands, neutralizing antibodies and EGFR inhibitors on mechanotransduction and we found that EGF via EGFR increased the response to mechanical strain. Results were confirmed by qPCR analysis of mechanoresponsive genes. EGF-responsive interleukin-6 and interleukin-8 were synergistically enhanced by EGF stimulation and mechanical strain. We show here in immortalized and primary BMSC that EGFR signaling enhances mechanotransduction, indicating that the EGF system is a mechanosensitizer in BMSC. Alterations in mechanosensitivity and -adaptation are contributors to age-related diseases like osteoporosis and the identification of a suitable mechanosensitizer could be beneficial. The role of the synergism of these signaling cascades in physiology and disease remains to be unraveled.}, language = {en} } @article{ReichertvonRottkayRothetal.2018, author = {Reichert, Johannes C. and von Rottkay, Eberhard and Roth, Franz and Renz, Tim and Hausmann, Johannes and Kranz, Julius and Rackwitz, Lars and N{\"o}th, Ulrich and Rudert, Maximilian}, title = {A prospective randomized comparison of the minimally invasive direct anterior and the transgluteal approach for primary total hip arthroplasty}, series = {BMC Musculoskeletal Disorders}, volume = {19}, journal = {BMC Musculoskeletal Disorders}, number = {241}, doi = {10.1186/s12891-018-2133-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176072}, year = {2018}, abstract = {Background: The presented prospective randomized controlled single-centre study compares the clinical outcome up to 12 months after total hip arthroplasty using a minimally invasive single-incision direct anterior (DAA) and a direct transgluteal lateral approach. Methods: A total of 123 arthroplasties were evaluated utilizing the Harris Hip Score (HHS), the extra short musculoskeletal functional assessment questionnaire (XSFMA), the Short Form 36 (SF-36) health survey, a Stepwatch™ Activity Monitor (SAM), and a timed 25 m foot walk (T25-FW). Postoperative x-ray images after THA were reviewed to determine inclination and stem positioning. Results: At final follow-up, the XSFMA functional index scores were 10.3 (anterior) and 15.08 (lateral) while the bother index summed up to a score of 15.8 (anterior) and 21.66 (lateral) respectively, thus only differing significantly for the functional index (p = 0.040 and p = 0.056). The SF-36 physical component score (PCS) was 47.49 (anterior) and 42.91 (lateral) while the mental component score (MCS) summed up to 55.0 (anterior) and 56.23 (lateral) with a significant difference evident for the PCS (p = 0.017; p = 0.714). Patients undergoing THA through a DAA undertook a mean of 6402 cycles per day while those who had undergone THA through a transgluteal approach undertook a mean of 5340 cycles per day (p = 0.012). Furthermore, the obtained outcome for the T25-FW with 18.4 s (anterior) and 19.75 s (lateral) and the maximum walking distance (5932 m and 5125 m) differed significantly (p = 0.046 and p = 0.045). The average HHS showed no significant difference equaling 92.4 points in the anterior group and 91.43 in the lateral group (p = 0.477). The radiographic analysis revealed an average cup inclination of 38.6° (anterior) and 40.28° (lateral) without signs of migration. Conclusion: In summary, our outcomes show that after 1 year THA through the direct anterior approach results in a higher patient activity compared to THA utilizing a transgluteal lateral approach while no differences regarding hip function are evident.}, language = {en} } @article{BoelchRothArnholdtetal.2018, author = {Boelch, Sebastian P. and Roth, Magnus and Arnholdt, Joerg and Rudert, Maximilian and Luedemann, Martin}, title = {Synovial fluid aspiration should not be routinely performed during the two-stage exchange of the knee}, series = {BioMed Research International}, volume = {2018}, journal = {BioMed Research International}, number = {6720712}, doi = {10.1155/2018/6720712}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176800}, year = {2018}, abstract = {Purpose. Detection of infection persistence during the two-stage exchange of the knee for periprosthetic joint infection is challenging. Synovial fluid culture (SFC) and synovial white blood cell count (SWBCC) before joint reimplantation are widespread diagnostic means for this indication. The sensitivity and specificity of SFC and of SWBCC for infection persistence before planned reimplantation were evaluated. Methods. 94 two-stage exchanges of the knee with synovial fluid aspiration performed after a drug holiday of at least 14 days and before reimplantation or spacer exchange (planned reimplantation) were retrospectively analyzed. Only cases with at least 3 intraoperative samples at planned reimplantation were included. SFC and SWBCC were compared to pathogen detection (SFC\(_{(culture)}\)/SWBCC\(_{(culture)}\) and to histopathological signs of infection persistence (SFC\(_{(histo)}\)/SWBCC\(_{(histo)}\) from intraoperative samples at planned reimplantation. For SFC, the sensitivity and specificity were calculated. For SWBCC, the optimal cut-off value with its sensitivity and specificity was calculated with the Youden-Index. Results. Sensitivity and specificity of SFC\(_{(culture)}\) were 0.0\% and 98.9\%. Sensitivity and specificity of SFC\(_{(histo)}\) were 3.4\% and 100\%. The optimal cut-off value for SWBCC\(_{(culture)}\) was 4450 cells/μl with a sensitivity of 50.0\% and a specificity of 86.5\%. The optimal cut-off value for SWBCC\(_{(histo)}\) was 3250 cells/μl with a sensitivity of 35.7\% and a specificity of 92.9\%. Conclusion. The detection of infection persistence remains challenging and a consented approach is lacking. The results do not warrant the routine performance of SFC during the two-stage exchange at the knee. SWBCC can be used to confirm infection persistence at high cut-offs, but they only occur in few patients and are therefore inappropriate for the routine use.}, language = {en} } @article{BoelchGurokGilbertetal.2021, author = {Boelch, Sebastian P. and Gurok, Anna and Gilbert, Fabian and Weißenberger, Manuel and Rudert, Maximilian and Barthel, Thomas and Reppenhagen, Stephan}, title = {Why compromise the patella? Five-year follow-up results of medial patellofemoral ligament reconstruction with soft tissue patellar fixation}, series = {International Orthopaedics}, volume = {45}, journal = {International Orthopaedics}, issn = {0341-2695}, doi = {10.1007/s00264-020-04922-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235751}, pages = {1493-1500}, year = {2021}, abstract = {Purpose This study investigates the redislocation rate and functional outcome at a minimum follow-up of five years after medial patellofemoral ligament (MPFL) reconstruction with soft tissue patellar fixation for patella instability. Methods Patients were retrospectively identified and knees were evaluated for trochlea dysplasia according to Dejour, for presence of patella alta and for presence of cartilage lesion at surgery. At a minimum follow-up of five years, information about an incident of redislocation was obtained. Kujala, Lysholm, and Tegner questionnaires as well as range of motion were used to measure functional outcome. Results Eighty-nine knees were included. Follow-up rate for redislocation was 79.8\% and for functional outcome 58.4\%. After a mean follow-up of 5.8 years, the redislocation rate was 5.6\%. There was significant improvement of the Kujala score (68.8 to 88.2, p = 0.000) and of the Lysholm score (71.3 to 88.4, p = 0.000). Range of motion at follow-up was 149.0° (115-165). 77.5\% of the knees had patella alta and 52.9\% trochlear dysplasia types B, C, or D. Patellar cartilage legions were present in 54.2\%. Redislocations occurred in knees with trochlear dysplasia type C in combination with patella alta. Conclusion MPFL reconstruction with soft tissue patellar fixation leads to significant improvement of knee function and low midterm redislocation rate. Patients with high-grade trochlear dysplasia should be considered for additional osseous correction.}, language = {en} } @article{GenestRakBaetzetal.2021, author = {Genest, Franca and Rak, Dominik and B{\"a}tz, Elisa and Ott, Kerstin and Seefried, Lothar}, title = {Sarcopenia and Malnutrition Screening in Female Osteoporosis Patients — A Cross-Sectional Study}, series = {Journal of Clinical Medicine}, volume = {10}, journal = {Journal of Clinical Medicine}, number = {11}, issn = {2077-0383}, doi = {10.3390/jcm10112344}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239658}, year = {2021}, abstract = {Sarcopenia and malnutrition are important determinants of increased fracture risk in osteoporosis. SARC-F and MNA-SF are well-established questionnaires for identifying patients at risk for these conditions. We sought to evaluate the feasibility and potential added benefit of such assessments as well as the actual prevalence of these conditions in osteoporosis patients. We conducted a cross-sectional, single-center study in female osteoporosis patients ≥ 65 years (SaNSiBaR-study). Results of the sarcopenia (SARC-F) and malnutrition (MNA-SF) screening questionnaires were matched with a functional assessment for sarcopenia and data from patients' medical records. Out of 107 patients included in the analysis, a risk for sarcopenia (SARC-F ≥ 4 points) and a risk for malnutrition (MNA-SF ≤ 11 points) was found in 33 (30.8\%) and 38 (35.5\%) patients, respectively. Diagnostic overlap with coincident indicative findings in both questionnaires was observed in 17 patients (16\%). As compared to the respective not-at-risk groups, the mean short physical performance battery (SPPB) score was significantly reduced in both patients at risk for sarcopenia (7.0 vs. 10.9 points, p < 0.001) and patients at risk for malnutrition (8.7 vs. 10.5 points, p = 0.005). Still, confirmed sarcopenia according to EWGSOP2 criteria was present in only 6 (6\%) of all 107 patients, with only 3 of them having an indicative SARC-F score. Bone mineral density was not significantly different in any of the at-risk groups at any site. In summary, applying SARC-F and MNA-SF in osteoporosis patients appears to be a complementary approach to identify individuals with functional deficits.}, language = {en} } @article{LiedertNemitzHaffnerLuntzeretal.2020, author = {Liedert, Astrid and Nemitz, Claudia and Haffner-Luntzer, Melanie and Schick, Fabian and Jakob, Franz and Ignatius, Anita}, title = {Effects of estrogen receptor and Wnt signaling activation on mechanically induced bone formation in a mouse model of postmenopausal bone loss}, series = {International Journal of Molecular Sciences}, volume = {21}, journal = {International Journal of Molecular Sciences}, number = {21}, issn = {1422-0067}, doi = {10.3390/ijms21218301}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-285487}, year = {2020}, abstract = {In the adult skeleton, bone remodeling is required to replace damaged bone and functionally adapt bone mass and structure according to the mechanical requirements. It is regulated by multiple endocrine and paracrine factors, including hormones and growth factors, which interact in a coordinated manner. Because the response of bone to mechanical signals is dependent on functional estrogen receptor (ER) and Wnt/β-catenin signaling and is impaired in postmenopausal osteoporosis by estrogen deficiency, it is of paramount importance to elucidate the underlying mechanisms as a basis for the development of new strategies in the treatment of osteoporosis. The present study aimed to investigate the effectiveness of the activation of the ligand-dependent ER and the Wnt/β-catenin signal transduction pathways on mechanically induced bone formation using ovariectomized mice as a model of postmenopausal bone loss. We demonstrated that both pathways interact in the regulation of bone mass adaption in response to mechanical loading and that the activation of Wnt/β-catenin signaling considerably increased mechanically induced bone formation, whereas the effects of estrogen treatment strictly depended on the estrogen status in the mice.}, language = {en} } @article{NedopilDhaliwalHowelletal.2022, author = {Nedopil, Alexander J. and Dhaliwal, Anand and Howell, Stephen M. and Hull, Maury L.}, title = {A surgeon that switched to unrestricted kinematic alignment with manual instruments has a short learning curve and comparable resection accuracy and outcomes to those of an experienced surgeon}, series = {Journal of Personalized Medicine}, volume = {12}, journal = {Journal of Personalized Medicine}, number = {7}, issn = {2075-4426}, doi = {10.3390/jpm12071152}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-281842}, year = {2022}, abstract = {After starting an orthopedic practice, a surgeon with a fellowship in mechanically aligned (MA) TKA initiated this study to characterize their learning curve after they switched to unrestricted kinematic alignment (KA) TKA using manual instruments. Accordingly, the present study determined for the inexperienced (IE) surgeon the number of cases required to achieve consistent femoral resections and operating times, and whether the femoral resection accuracy, patient-reported outcome measures (PROMs), and component alignment were different from an experienced (E) surgeon. This prospective cohort study analyzed the IE surgeon's first 30 TKAs, all performed with KA, and 30 consecutive KA TKAs performed by an E surgeon. The resection accuracy or deviation was the calipered thickness of the distal and posterior medial and lateral femoral resections minus the planned resection thickness, which was the thickness of the corresponding condyle of the femoral component, minus 2 mm for cartilage wear, and 1 mm for the kerf of the blade. Independent observers recorded the femoral resection thickness, operative times, PROMs, and alignment. For each femoral resection, the deviation between three groups of patients containing ten consecutive KA TKAs, was either insignificant (p = 0.695 to 1.000) or within the 0.5 mm resolution of the caliper, which indicated no learning curve. More than three groups were needed to determine the learning curve for the operative time; however, the IE surgeon's procedure dropped to 77 min for the last 10 patients, which was 20 min longer than the E surgeon. The resection deviations of the IE and E surgeon were comparable, except for the posterolateral femoral resection, which the IE surgeon under-resected by a mean of -0.8 mm (p < 0.0001). At a mean follow-up of 9 and 17 months, the Forgotten Joint Score, Oxford Knee Score, KOOS, and the alignment of the components and limbs were not different between the IE and E surgeon (p ≥ 0.6994). A surgeon that switches to unrestricted KA with manual instruments can determine their learning curve by computing the deviation of the distal and posterior femoral resections from the planned resection. Based on the present study, an IE surgeon could have resection accuracy, post-operative patient outcomes, and component alignment comparable to an E surgeon.}, language = {en} } @article{HorasvanHerckMaieretal.2020, author = {Horas, Konstantin and van Herck, Ulrike and Maier, Gerrit S. and Maus, Uwe and Harrasser, Norbert and Jakob, Franz and Weissenberger, Manuel and Arnholdt, J{\"o}rg and Holzapfel, Boris M. and Rudert, Maximilian}, title = {Does vitamin D deficiency predict tumour malignancy in patients with bone tumours? Data from a multi-center cohort analysis}, series = {Journal of Bone Oncology}, volume = {25}, journal = {Journal of Bone Oncology}, doi = {10.1016/j.jbo.2020.100329}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230314}, year = {2020}, abstract = {Vitamin D deficiency is a global health concern that is estimated to afflict over one billion people globally. The major role of vitamin D is that of a regulator of calcium and phosphate metabolism, thus, being essential for proper bone mineralisation. Concomitantly, vitamin D is known to exert numerous extra-skeletal actions. For example, it has become evident that vitamin D has direct anti-proliferative, pro-differentiation and pro-apoptotic actions on cancer cells. Hence, vitamin D deficiency has been associated with increased cancer risk and worse prognosis in several malignancies. We have recently demonstrated that vitamin D deficiency promotes secondary cancer growth in bone. These findings were partly attributable to an increase in bone remodelling but also through direct effects of vitamin D on cancer cells. To date, very little is known about vitamin D status of patients with bone tumours in general. Thus, the objective of this study was to assess vitamin D status of patients with diverse bone tumours. Moreover, the aim was to elucidate whether or not there is an association between pre-diagnostic vitamin D status and tumour malignancy in patients with bone tumours. In a multi-center analysis, 25(OH)D, PTH and calcium levels of 225 patients that presented with various bone tumours between 2017 and 2018 were assessed. Collectively, 76\% of all patients had insufficient vitamin D levels with a total mean 25(OH)D level of 21.43 ng/ml (53.58 nmol/L). In particular, 52\% (117/225) of patients were identified as vitamin D deficient and further 24\% of patients (55/225) were vitamin D insufficient. Notably, patients diagnosed with malignant bone tumours had significantly lower 25(OH)D levels than patients diagnosed with benign bone tumours [19.3 vs. 22.75 ng/ml (48.25 vs. 56.86 nmol/L); p = 0.04). In conclusion, we found a widespread and distressing rate of vitamin D deficiency and insufficiency in patients with bone tumours. However, especially for patients with bone tumours sufficient vitamin D levels seem to be of great importance. Thus, we believe that 25(OH)D status should routinely be monitored in these patients. Collectively, there should be an increased awareness for physicians to assess and if necessary correct vitamin D status of patients with bone tumours in general or of those at great risk of developing bone tumours.}, language = {en} } @article{OhlebuschBorstFrankenbachetal.2020, author = {Ohlebusch, Barbara and Borst, Angela and Frankenbach, Tina and Klopocki, Eva and Jakob, Franz and Liedtke, Daniel and Graser, Stephanie}, title = {Investigation of alpl expression and Tnap-activity in zebrafish implies conserved functions during skeletal and neuronal development}, series = {Scientific Reports}, volume = {10}, journal = {Scientific Reports}, doi = {10.1038/s41598-020-70152-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230024}, year = {2020}, abstract = {Hypophosphatasia (HPP) is a rare genetic disease with diverse symptoms and a heterogeneous severity of onset with underlying mutations in the ALPL gene encoding the ectoenzyme Tissue-nonspecific alkaline phosphatase (TNAP). Considering the establishment of zebrafish (Danio rerio) as a new model organism for HPP, the aim of the study was the spatial and temporal analysis of alpl expression in embryos and adult brains. Additionally, we determined functional consequences of Tnap inhibition on neural and skeletal development in zebrafish. We show that expression of alpl is present during embryonic stages and in adult neuronal tissues. Analyses of enzyme function reveal zones of pronounced Tnap-activity within the telencephalon and the mesencephalon. Treatment of zebrafish embryos with chemical Tnap inhibitors followed by axonal and cartilage/mineralized tissue staining imply functional consequences of Tnap deficiency on neuronal and skeletal development. Based on the results from neuronal and skeletal tissue analyses, which demonstrate an evolutionary conserved role of this enzyme, we consider zebrafish as a promising species for modeling HPP in order to discover new potential therapy strategies in the long-term.}, language = {en} } @article{ReichelRuecklFenwicketal.2019, author = {Reichel, Thomas and Rueckl, Kilian and Fenwick, Annabel and Vogt, Niklas and Rudert, Maximilian and Plumhoff, Piet}, title = {Hibernoma of the upper extremity: complete case of a rare but benign soft tissue tumor}, series = {Case Reports in Orthopedics}, volume = {2019}, journal = {Case Reports in Orthopedics}, doi = {10.1155/2019/6840693}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201669}, pages = {6840693}, year = {2019}, abstract = {Hibernoma is a rare benign lipomatous tumor showing differentiation of brown fatty tissue. To the author's best knowledge, there is no known case of malignant transformation or metastasis. Due to their slow, noninfiltrating growth hibernomas are often an incidental finding in the third or fourth decade of life. The vast majority are located in the thigh, neck, and periscapular region. A diagnostic workup includes ultrasound and contrast-enhanced MRI. Differential diagnosis is benign lipoma, well-differentiated liposarcoma, and rhabdomyoma. An incisional biopsy followed by marginal resection of the tumor is the standard of care, and recurrence after complete resection is not reported. The current paper presents diagnostic and intraoperative findings of a hibernoma of the upper arm and reviews similar reports in the current literature.}, language = {en} } @article{HeinzMellerLuetkensetal.2023, author = {Heinz, Tizian and Meller, Felix and Luetkens, Karsten Sebastian and Anderson, Philip Mark and Stratos, Ioannis and Horas, Konstantin and Rudert, Maximilian and Reppenhagen, Stephan and Weißenberger, Manuel}, title = {The AMADEUS score is not a sufficient predictor for functional outcome after high tibial osteotomy}, series = {Journal of Experimental Orthopaedics}, volume = {10}, journal = {Journal of Experimental Orthopaedics}, doi = {10.1186/s40634-023-00575-2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357765}, year = {2023}, abstract = {Purpose The Area Measurement And Depth Underlying Structures (AMADEUS) classification system has been proposed as a valuable tool for magnetic resonance (MR)-based grading of preoperatively encountered chondral defects of the knee joint. However, the potential relationship of this novel score with clinical data was yet to determine. It was the primary intention of this study to assess the correlative relationship of the AMADEUS with patient reported outcome scores in patients undergoing medial open-wedge high tibial valgus osteotomy (HTO). Furthermore, the arthroscopic ICRS (International Cartilage Repair Society) grade evaluation was tested for correlation with the AMADEUS classification system. Methods This retrospective, monocentric study found a total of 70 individuals that were indicated for HTO due to degenerative chondral defects of the medial compartment between 2008 and 2019. A preoperative MR image as well as a pre-osteotomy diagnostic arthroscopy for ICRS grade evaluation was mandatory for all patients. The Knee Osteoarthritis Outcome Score (KOOS) including its five subscale scores (KOOS-ADL, KOOS-QOL, KOOS-Sports, KOOS-Pain, KOOS-Symptoms) was obtained preoperatively and at a mean follow-up of 41.2 ± 26.3 months. Preoperative chondral defects were evaluated using the AMADEUS classification system and the final AMADEUS scores were correlated with the pre- and postoperative KOOS subscale sores. Furthermore, arthroscopic ICRS defect severity was correlated with the AMADEUS classification system. Results There was a statistically significant correlation between the AMADEUS BME (bone marrow edema) subscore and the KOOS Symptoms subscore at the preoperative visit (r = 0.25, p = 0.04). No statistically significant monotonic association between the AMADEUS total score and the AMADEUS grade with pre- and postoperative KOOS subscale scores were found. Intraoperatively obtained ICRS grade did reveal a moderate correlative relation with the AMADEUS total score and the AMADEUS grade (r = 0.28, p = 0.02). Conclusions The novel AMADEUS classification system largely lacks correlative capacity with patient reported outcome measures in patients undergoing HTO. The MR tomographic appearance of bone marrow edema is the only parameter predictive of the clinical outcome at the preoperative visit.}, language = {en} } @article{MunawarZhouPrommersbergeretal.2023, author = {Munawar, Umair and Zhou, Xiang and Prommersberger, Sabrina and Nerreter, Silvia and Vogt, Cornelia and Steinhardt, Maximilian J. and Truger, Marietta and Mersi, Julia and Teufel, Eva and Han, Seungbin and Haertle, Larissa and Banholzer, Nicole and Eiring, Patrick and Danhof, Sophia and Navarro-Aguadero, Miguel Angel and Fernandez-Martin, Adrian and Ortiz-Ruiz, Alejandra and Barrio, Santiago and Gallardo, Miguel and Valeri, Antonio and Castellano, Eva and Raab, Peter and Rudert, Maximilian and Haferlach, Claudia and Sauer, Markus and Hudecek, Michael and Martinez-Lopez, J. and Waldschmidt, Johannes and Einsele, Hermann and Rasche, Leo and Kort{\"u}m, K. Martin}, title = {Impaired FADD/BID signaling mediates cross-resistance to immunotherapy in Multiple Myeloma}, series = {Communications Biology}, volume = {6}, journal = {Communications Biology}, doi = {10.1038/s42003-023-05683-4}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357609}, year = {2023}, abstract = {The treatment landscape in multiple myeloma (MM) is shifting from genotoxic drugs to immunotherapies. Monoclonal antibodies, immunoconjugates, T-cell engaging antibodies and CART cells have been incorporated into routine treatment algorithms, resulting in improved response rates. Nevertheless, patients continue to relapse and the underlying mechanisms of resistance remain poorly understood. While Impaired death receptor signaling has been reported to mediate resistance to CART in acute lymphoblastic leukemia, this mechanism yet remains to be elucidated in context of novel immunotherapies for MM. Here, we describe impaired death receptor signaling as a novel mechanism of resistance to T-cell mediated immunotherapies in MM. This resistance seems exclusive to novel immunotherapies while sensitivity to conventional anti-tumor therapies being preserved in vitro. As a proof of concept, we present a confirmatory clinical case indicating that the FADD/BID axis is required for meaningful responses to novel immunotherapies thus we report impaired death receptor signaling as a novel resistance mechanism to T-cell mediated immunotherapy in MM.}, language = {en} } @article{WeissenbergerWagenbrennerNickeletal.2023, author = {Weißenberger, Manuel and Wagenbrenner, Mike and Nickel, Joachim and Ahlbrecht, Rasmus and Blunk, Torsten and Steinert, Andre F. and Gilbert, Fabian}, title = {Comparative in vitro treatment of mesenchymal stromal cells with GDF-5 and R57A induces chondrogenic differentiation while limiting chondrogenic hypertrophy}, series = {Journal of Experimental Orthopaedics}, volume = {10}, journal = {Journal of Experimental Orthopaedics}, doi = {10.1186/s40634-023-00594-z}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357770}, year = {2023}, abstract = {Purpose Hypertrophic cartilage is an important characteristic of osteoarthritis and can often be found in patients suffering from osteoarthritis. Although the exact pathomechanism remains poorly understood, hypertrophic de-differentiation of chondrocytes also poses a major challenge in the cell-based repair of hyaline cartilage using mesenchymal stromal cells (MSCs). While different members of the transforming growth factor beta (TGF-β) family have been shown to promote chondrogenesis in MSCs, the transition into a hypertrophic phenotype remains a problem. To further examine this topic we compared the effects of the transcription growth and differentiation factor 5 (GDF-5) and the mutant R57A on in vitro chondrogenesis in MSCs. Methods Bone marrow-derived MSCs (BMSCs) were placed in pellet culture and in-cubated in chondrogenic differentiation medium containing R57A, GDF-5 and TGF-ß1 for 21 days. Chondrogenesis was examined histologically, immunohistochemically, through biochemical assays and by RT-qPCR regarding the expression of chondrogenic marker genes. Results Treatment of BMSCs with R57A led to a dose dependent induction of chondrogenesis in BMSCs. Biochemical assays also showed an elevated glycosaminoglycan (GAG) content and expression of chondrogenic marker genes in corresponding pellets. While treatment with R57A led to superior chondrogenic differentiation compared to treatment with the GDF-5 wild type and similar levels compared to incubation with TGF-ß1, levels of chondrogenic hypertrophy were lower after induction with R57A and the GDF-5 wild type. Conclusions R57A is a stronger inducer of chondrogenesis in BMSCs than the GDF-5 wild type while leading to lower levels of chondrogenic hypertrophy in comparison with TGF-ß1.}, language = {en} } @article{BaumbachHoertererOppeltetal.2022, author = {Baumbach, Sebastian Felix and H{\"o}rterer, Hubert and Oppelt, Sonja and Szeimies, Ulrike and Polzer, Hans and Walther, Markus}, title = {Do pre-operative radiologic assessment predict postoperative outcomes in patients with insertional Achilles tendinopathy?: a retrospective database study}, series = {Archives of Orthopaedic and Trauma Surgery}, volume = {142}, journal = {Archives of Orthopaedic and Trauma Surgery}, number = {11}, issn = {1434-3916}, doi = {10.1007/s00402-021-03897-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-307963}, pages = {3045-3052}, year = {2022}, abstract = {Introduction Diagnosis and treatment of insertional tendinopathy of the Achilles tendon (IAT) remains a challenge. The aim of this study was to assess the influence of pre-operative radiological pathologies on the patient-reported outcomes following open debridement of all pathologies for IAT. Materials and methods In this IRB-approved retrospective correlation and comparative study, patients with pre-operative imaging were identified from the authors' retrospective IAT database comprising of 118 patients. All were treated by a standardized surgical treatment strategy utilizing a midline, transachillary approach and debridement of all pathologies. A total of fifteen radiologic parameters were measured on radiographs (RX) and MRI. The patient-reported outcomes were assessed using the Victorian Institute of Sport Assessment-Achilles questionnaire (VISA-A-G) and the general health questionnaire SF-12 at a minimum follow-up of 12 months. The data are presented as mean ± SD (95\% CI). Results 88 patients (74.6\%) with an average age of 50 ± 12 (47-52) years were included. Radiographs were available in 68 patients and MRI in 53. The mean follow-up was 3.8 ± 1.9 (3.4-4.3) years. The overall VISA-A-G was 81 ± 22 (77-86), the SF-12 PCS 54 ± 7 (52-55), and the SF-12 MCS 52 ± 9 (50-54) points. None of the assessed radiological parameters had a significant influence on the patient-reported outcome following surgical treatment for IAT. Conclusion In this retrospective correlation study, no significant association was found between preoperative radiographic and MRI radiologic parameters for IAT and postoperative patient-reported outcomes (VISA-A-G and SF-12).}, language = {en} } @article{LuetkensGrunzKunzetal.2023, author = {Luetkens, Karsten Sebastian and Grunz, Jan-Peter and Kunz, Andreas Steven and Huflage, Henner and Weißenberger, Manuel and Hartung, Viktor and Patzer, Theresa Sophie and Gruschwitz, Philipp and Erg{\"u}n, S{\"u}leyman and Bley, Thorsten Alexander and Feldle, Philipp}, title = {Ultra-high-resolution photon-counting detector CT arthrography of the ankle: a feasibility study}, series = {Diagnostics}, volume = {13}, journal = {Diagnostics}, number = {13}, issn = {2075-4418}, doi = {10.3390/diagnostics13132201}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-362622}, year = {2023}, abstract = {This study was designed to investigate the image quality of ultra-high-resolution ankle arthrography employing a photon-counting detector CT. Bilateral arthrograms were acquired in four cadaveric specimens with full-dose (10 mGy) and low-dose (3 mGy) scan protocols. Three convolution kernels with different spatial frequencies were utilized for image reconstruction (ρ\(_{50}\); Br98: 39.0, Br84: 22.6, Br76: 16.5 lp/cm). Seven radiologists subjectively assessed the image quality regarding the depiction of bone, hyaline cartilage, and ligaments. An additional quantitative assessment comprised the measurement of noise and the computation of contrast-to-noise ratios (CNR). While an optimal depiction of bone tissue was achieved with the ultra-sharp Br98 kernel (S ≤ 0.043), the visualization of cartilage improved with lower modulation transfer functions at each dose level (p ≤ 0.014). The interrater reliability ranged from good to excellent for all assessed tissues (intraclass correlation coefficient ≥ 0.805). The noise levels in subcutaneous fat decreased with reduced spatial frequency (p \< 0.001). Notably, the low-dose Br76 matched the CNR of the full-dose Br84 (p 0.999) and superseded Br98 (p \< 0.001) in all tissues. Based on the reported results, a photon-counting detector CT arthrography of the ankle with an ultra-high-resolution collimation offers stellar image quality and tissue assessability, improving the evaluation of miniscule anatomical structures. While bone depiction was superior in combination with an ultra-sharp convolution kernel, soft tissue evaluation benefited from employing a lower spatial frequency.}, language = {en} } @article{PereiraLipphausErginetal.2021, author = {Pereira, Ana Rita and Lipphaus, Andreas and Ergin, Mert and Salehi, Sahar and Gehweiler, Dominic and Rudert, Maximilian and Hansmann, Jan and Herrmann, Marietta}, title = {Modeling of the Human Bone Environment: Mechanical Stimuli Guide Mesenchymal Stem Cell-Extracellular Matrix Interactions}, series = {Materials}, volume = {14}, journal = {Materials}, number = {16}, issn = {1996-1944}, doi = {10.3390/ma14164431}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-245012}, year = {2021}, abstract = {In bone tissue engineering, the design of in vitro models able to recreate both the chemical composition, the structural architecture, and the overall mechanical environment of the native tissue is still often neglected. In this study, we apply a bioreactor system where human bone-marrow hMSCs are seeded in human femoral head-derived decellularized bone scaffolds and subjected to dynamic culture, i.e., shear stress induced by continuous cell culture medium perfusion at 1.7 mL/min flow rate and compressive stress by 10\% uniaxial load at 1 Hz for 1 h per day. In silico modeling revealed that continuous medium flow generates a mean shear stress of 8.5 mPa sensed by hMSCs seeded on 3D bone scaffolds. Experimentally, both dynamic conditions improved cell repopulation within the scaffold and boosted ECM production compared with static controls. Early response of hMSCs to mechanical stimuli comprises evident cell shape changes and stronger integrin-mediated adhesion to the matrix. Stress-induced Col6 and SPP1 gene expression suggests an early hMSC commitment towards osteogenic lineage independent of Runx2 signaling. This study provides a foundation for exploring the early effects of external mechanical stimuli on hMSC behavior in a biologically meaningful in vitro environment, opening new opportunities to study bone development, remodeling, and pathologies.}, language = {en} } @article{SeefriedRakPetryketal.2021, author = {Seefried, L. and Rak, D. and Petryk, A. and Genest, F.}, title = {Bone turnover and mineral metabolism in adult patients with hypophosphatasia treated with asfotase alfa}, series = {Osteoporosis International}, volume = {32}, journal = {Osteoporosis International}, number = {12}, doi = {10.1007/s00198-021-06025-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265310}, pages = {2505-2513}, year = {2021}, abstract = {Summary There is limited understanding of how asfotase alfa affects mineral metabolism and bone turnover in adults with pediatric-onset hypophosphatasia. This study showed that adults with hypophosphatasia treated with asfotase alfa experienced significant changes in biochemical markers of bone and mineral metabolism, possibly reflecting enhanced bone remodeling of previously osteomalacic bone. Introduction Hypophosphatasia (HPP), due to a tissue nonspecific alkaline phosphatase (TNSALP) deficiency, can cause impaired bone mineralization and turnover. Although HPP may be treated with asfotase alfa, an enzyme replacement therapy, limited data are available on how treatment with asfotase alfa affects mineral metabolism and bone turnover in adults with HPP. Methods ALP substrates, bone turnover and mineral metabolism markers, and bone mineral density (BMD) data from EmPATHY, a single-center, observational study of adults (≥ 18 years) with pediatric-onset HPP treated with asfotase alfa (NCT03418389), were collected during routine clinical care and analyzed from baseline through 24 months of treatment. Results Data from 21 patients showed significantly increased ALP activity and reduced urine phosphoethanolamine (PEA)/creatinine (Cr) ratios after baseline through 24 months of asfotase alfa treatment. There were significant transient increases in parathyroid hormone 1-84 (PTH), osteocalcin, and procollagen type 1 N-propeptide (P1NP) levels at 3 and 6 months and in tartrate-resistant acid phosphatase 5b (TRAP5b) levels at 3 months, with a significant decrease in N-terminal telopeptide of type 1 collagen (NTX) levels at 24 months. Lumbar spine BMD T scores continuously increased during treatment. Conclusion Significant changes in bone turnover and mineral metabolism markers after asfotase alfa treatment suggest that treatment-mediated mineralization may enable remodeling and bone turnover on previously unmineralized surfaces. Urine PEA/Cr ratios may be a useful parameter in monitoring treatment during routine care.}, language = {en} } @article{GenestClaussenRaketal.2021, author = {Genest, F. and Claußen, L. and Rak, D. and Seefried, L.}, title = {Bone mineral density and fracture risk in adult patients with hypophosphatasia}, series = {Osteoporosis International}, volume = {32}, journal = {Osteoporosis International}, issn = {0937-941X}, doi = {10.1007/s00198-020-05612-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235793}, pages = {377-385}, year = {2021}, abstract = {Summary In adult hypophosphatasia (HPP) patients, elevated lumbar spine dual X-ray absorptiometry (DXA) values are associated with markers of disease severity and disease-specific fracture risk while femoral bone mineral density (BMD), being largely unaffected by the disease severity, may still be useful to monitor other causes of increased fracture risk due to low BMD. Introduction Hypophosphatasia (HPP) is a rare inherited metabolic disorder due to deficient activity of the tissue-nonspecific alkaline phosphatase (TNAP). Clinical manifestation in adult HPP patients is manifold including an increased risk for fractures, but data regarding clinical significance of DXA measurement and associations with fracture risk and disease severity is scarce. Methods Retrospective single-center analysis of DXA scans in patients with confirmed HPP (documented mutation, clinical symptoms, low alkaline phosphatase activity). Further data evaluation included disease-related fractures, laboratory results (alkaline phosphatase, pyridoxalphosphate, phosphoethanolamine), and medical history. Results Analysis included 110 patients (84 female, mean age of 46.2 years) of whom 37.3\% (n = 41) were harboring two mutations. Average T-Score level at the lumbar spine was - 0.1 (SD 1.9), and mean total hip T-Score was - 1.07 (SD 0.15). Both lower ALP activity and higher substrate levels (pyridoxalphosphate and phosphoethanolamine) were significantly correlated with increased lumbar spine T-Score levels (p < 0.001) while BMD at the hip was not affected by indicators of disease severity. Increased lumbar spine BMD was significantly associated with an increased risk for HPP-related fractures, prevalent in 22 (20\%) patients (p < 0.001) with 21 of them having biallelic mutations. Conclusion BMD in adult HPP patients is not systematically reduced. Conversely, increased lumbar spine BMD appears to be associated with severely compromised mineralization and increased risk for HPP-related fractures while BMD at the hip appears unaffected by indicators of disease severity, suggesting suitability of this anatomic location for assessing and discerning disorders with increased fracture risk owing to reduced BMD like osteoporosis. Trial registration number German register for clinical studies (DRKS00014022) Date of registration 02/10/2018 - retrospectively registered}, language = {en} } @article{StratosBehrendtAnselmetal.2022, author = {Stratos, Ioannis and Behrendt, Ann-Kathrin and Anselm, Christian and Gonzalez, Aldebarani and Mittlmeier, Thomas and Vollmar, Brigitte}, title = {Inhibition of TNF-α restores muscle force, inhibits inflammation, and reduces apoptosis of traumatized skeletal muscles}, series = {Cells}, volume = {11}, journal = {Cells}, number = {15}, issn = {2073-4409}, doi = {10.3390/cells11152397}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-286094}, year = {2022}, abstract = {Background: Muscle injuries are common in humans and are often associated with irrecoverable damage and disability. Upon muscle injury, TNF-α signaling pathways modulate the healing process and are predominantly associated with tissue degradation. In this study we assumed that TNF-α inhibition could reduce the TNF-α-associated tissue degradation after muscle injury. Materials and methods: Therefore, the left soleus muscle of 42 male Wistar rats was injured using a standardized open muscle injury model. All rats were treated immediately after injury either with infliximab (single i.p. injection; 10 mg/kg b.w.) or saline solution i.p. Final measurements were conducted at day one, four, and 14 post injury. The muscle force, the muscle cell proliferation, the muscle cell coverage as well as the myofiber diameter served as read out parameters of our experiment. Results: Systemic application of infliximab could significantly reduce the TNF-α levels in the injured muscle at day four upon trauma compared to saline treated animals. The ratio of muscle weight to body weight was increased and the twitch muscle force showed a significant rise 14 days after trauma and TNF-α inhibition. Quantification of myofiber diameter in the penumbra zone showed a significant difference between both groups at day one and four after injury, indicated by muscle hypertrophy in the infliximab group. Planimetric analysis of the injured muscle at day 14 revealed increased muscle tissue fraction in the infliximab group compared to the control animals. Muscle cell proliferation did not differ between both groups. Conclusions: These data provide evidence that the TNF-α blockade positively regulates the restauration of skeletal muscles upon injury.}, language = {en} } @phdthesis{Altmann2023, author = {Altmann, Stephan}, title = {Characterization of Metabolic Glycoengineering in Mesenchymal Stromal Cells for its Application in thermoresponsive Bioinks}, doi = {10.25972/OPUS-29100}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-291003}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {This work developed during the first funding period of the subproject B05 in the framework of the interdisciplinary research consortium TRR 225 'From the Fundamentals of Biofabrication toward functional Tissue Models' and was part of a cooperation between the Orthopedic Department represented by Prof. Dr. Regina Ebert and the Institute of Organic Chemistry represented by Prof. Dr. J{\"u}rgen Seibel. This project dealed with cellular behavior during the bioprinting process and how to influence it by modifying the cell glycocalyx with functional target molecules. The focus was on the impact of potential shear stress, that cells experience when they get processed in thermoresponsive bioinks, and a way to increase the cell stiffness via metabolic glycoengineering to attenuate shear forces. For the characterization of the metabolic glycoengineering, four different peracetylated and four non-acetylated modified monosaccharides (two mannose and two sialic acid sugars) were tested in primary human mesenchymal stromal cells (hMSC) and telomerase-immortalized hMSC (hMSC-TERT). Viability results demonstrated a dose-dependent correlation for all sugars, at which hMSC-TERT seemed to be more susceptible leading to lower viability rates. The assessment of the incorporation efficiencies was performed by click chemistry using fluorescent dyes and revealed also a dose-dependent correlation for all mannose and sialic acid sugars, while glucose and galactose variants were not detected in the glycocalyx. However, incorporation efficiencies were highest when using mannose sugars in the primary hMSC. A subsequent analysis of the temporal retention of the incorporated monosaccharides showed a constant declining fluorescence signal up to 6 d for azido mannose in hMSC-TERT, whereas no signal could be detected for alkyne mannose after 2 d. Investigation of the differentiation potential and expression of different target genes revealed no impairment after incubation with mannose sugars, indicating a normal phenotype for hMSC-TERT. Following the successful establishment of the method, either a coumarin derivative or an artificial galectin 1 ligand were incorporated into the cell glycocalyx of hMSC-TERT as functional target molecule. The biophysical analysis via shear flow deformation cytometry revealed a slightly increased cell stiffness and lowered fluidity for both molecules. A further part of this project aimed to control lectin-mediated cell adhesion by artificial galectin 1 ligands. As that hypothesis was settled in the work group of Prof. Dr. J{\"u}rgen Seibel, this work supported with an initial characterization of galectin 1 as part of the hMSC biology. A stable galectin 1 expression at gene and protein level in both hMSC and hMSC-TERT could be confirmed, at which immunocytochemical stainings could detect the protein only in the glycocalyx. The treatment of hMSC-TERT with a galectin 1 ligand in different concentrations did not show an altered gene expression of galectin 1. However, these first data in addition to the investigation of stiffness confirmed the applicability of specific and artificial IV galectin 1 ligands in biofabrication approaches to alter cell properties of hMSC. To conclude, metabolic glycoengineering has been successfully implemented in hMSC and hMSC-TERT to introduce glycocalyx modifications which reside there for several days. A proof of concept was carried out by the increase of cell stiffness and fluidity by the incorporation of a coumarin derivative or an artificial galectin 1 ligand. For the characterization of shear stress impact on cells after printing in thermoresponsive bioinks, the processing of hMSC-TERT (mixing or additionally printing) with Pluronic F127 or Polyoxazoline-Polyoxazine (POx-POzi) polymer solution was investigated. While there were no changes in viability when using POx-POzi bioink, processing with Pluronic F127 indicated slightly lower viability and increased apoptosis activity. Assessment of cellular responses to potential shear stress showed no reorganization of the cytoskeleton independent of the bioink, but highly increased expression of the mechanoresponsive proto-oncogene c Fos which was more pronounced when using Pluronic F127 and just mixed with the bioinks. Interestingly, processing of the mechanoresponsive reporter cell line hMSC-TERT-AP1 revealed slightly elevated mechanotransduction activity when using POx-POzi polymer and just mixed with the bioinks as well. In conclusion, hMSC-TERT embedded in thermoresponsive bioinks might shortly experience shear stress during the printing process, but that did not lead to remarkable cell damage likely due to the rheological properties of the bioinks. Furthermore, the printing experiments also suggested that cells do not sense more shear stress when additionally printed.}, subject = {Glykobiologie}, language = {en} } @article{RakNedopilSayreetal.2022, author = {Rak, Dominik and Nedopil, Alexander J. and Sayre, Eric C. and Masri, Bassam A. and Rudert, Maximilian}, title = {Postoperative inpatient rehabilitation does not increase knee function after primary total knee arthroplasty}, series = {Journal of Personalized Medicine}, volume = {12}, journal = {Journal of Personalized Medicine}, number = {11}, issn = {2075-4426}, doi = {10.3390/jpm12111934}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297322}, year = {2022}, abstract = {Inpatient rehabilitation (IR) is a common postoperative protocol after total knee replacement (TKA). Because IR is expensive and should therefore be justified, this study determined the difference in knee function one year after TKA in patients treated with IR or outpatient rehabilitation, fast-track rehabilitation (FTR) in particular, which also entails a reduced hospital length of stay. A total of 205 patients were included in this multi-center prospective cohort study. Of the patients, 104 had primary TKA at a German university hospital and received IR, while 101 had primary TKA at a Canadian university hospital and received FTR. Patients receiving IR or FTR were matched by pre-operative demographics and knee function. Oxford Knee Score (OKS), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and EuroQol visual analogue scale (EQ-VAS) determined knee function one year after surgery. Patients receiving IR had a 2.8-point lower improvement in OKS (p = 0.001), a 6.7-point lower improvement in WOMAC (p = 0.063), and a 12.3-point higher improvement in EQ-VAS (p = 0.281) than patients receiving FTR. IR does not provide long-term benefits to patient recovery after primary uncomplicated TKA under the current rehabilitation regime.}, language = {en} } @article{SeilerEbertRudertetal.2022, author = {Seiler, Jonas and Ebert, Regina and Rudert, Maximilian and Herrmann, Marietta and Leich, Ellen and Weißenberger, Manuela and Horas, Konstantin}, title = {Bone metastases of diverse primary origin frequently express the VDR (vitamin D receptor) and CYP24A1}, series = {Journal of Clinical Medicine}, volume = {11}, journal = {Journal of Clinical Medicine}, number = {21}, issn = {2077-0383}, doi = {10.3390/jcm11216537}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297377}, year = {2022}, abstract = {Active vitamin D (1,25(OH)2D3) is known to exert direct anti-cancer actions on various malignant tissues through binding to the vitamin D receptor (VDR). These effects have been demonstrated in breast, prostate, renal and thyroid cancers, which all have a high propensity to metastasise to bone. In addition, there is evidence that vitamin D catabolism via 24-hydroxylase (CYP24A1) is altered in tumour cells, thus, reducing local active vitamin D levels in cancer cells. The aim of this study was to assess VDR and CYP24A1 expression in various types of bone metastases by using immunohistochemistry. Overall, a high total VDR protein expression was detected in 59\% of cases (39/66). There was a non-significant trend of high-grade tumours towards the low nuclear VDR expression (p = 0.07). Notably, patients with further distant metastases had a reduced nuclear VDR expression (p = 0.03). Furthermore, a high CYP24A1 expression was detected in 59\% (39/66) of bone metastases. There was a significant positive correlation between nuclear VDR and CYP24A1 expression (p = 0.001). Collectively, the VDR and CYP24A1 were widely expressed in a multitude of bone metastases, pointing to a potential role of vitamin D signalling in cancer progression. This is of high clinical relevance, as vitamin D deficiency is frequent in patients with bone metastases.}, language = {en} } @article{KippnichDuempertSchorscheretal.2022, author = {Kippnich, Maximilian and Duempert, Maximilian and Schorscher, Nora and Jordan, Martin C. and Kunz, Andreas S. and Meybohm, Patrick and Wurmb, Thomas}, title = {Simultaneous treatment of trauma patients in a dual room trauma suite with integrated movable sliding gantry CT system: an observational study}, series = {Scientific Reports}, volume = {12}, journal = {Scientific Reports}, number = {1}, doi = {10.1038/s41598-022-20491-2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-299695}, year = {2022}, abstract = {The trauma center of the University Hospital Wuerzburg has developed an advanced trauma pathway based on a dual-room trauma suite with an integrated movable sliding gantry CT-system. This enables simultaneous CT-diagnostics and treatment of two trauma patients. The focus of this study was to investigate the quality of the concept based on defined outcome criteria in this specific setting (time from arrival to initiation of CT scan: tCT; time from arrival to initiation of emergency surgery: tES). We analyzed all trauma patients admitted to the hospital's trauma suite from 1st May 2019 through 29th April 2020. Two subgroups were defined: trauma patients, who were treated without a second trauma patient present (group 1) and patients, who were treated simultaneously with another trauma patient (group 2). Simultaneous treatment was defined as parallel arrival within a period of 20 min. Of 423 included trauma patients, 46 patients (10.9\%) were treated simultaneously. Car accidents were the predominant trauma mechanism in this group (19.6\% vs. 47.8\%, p < 0.05). Prehospital life-saving procedures were performed with comparable frequency in both groups (intubation 43.5\% vs. 39\%, p = 0.572); pleural drainage 3.2\% vs. 2.2\%, p = 0.708; cardiopulmonary resuscitation 5\% vs. 2.2\%, p = 0.387). At hospital admission, patients in group 2 suffered significantly more pain (E-problem according to Advanced Trauma Life Support principles©; 29.2\% vs. 45.7\%, p < 0.05). There were no significant differences in the clinical treatment (emergency procedures, vasopressor and coagulant therapy, and transfusion of red blood cells). tCT was 6 (4-10) minutes (median and IQR) in group 1 and 8 (5-15.5) minutes in group 2 (p = 0.280). tES was 90 (78-106) minutes in group 1 and 99 (97-108) minutes in group 2 (p = 0.081). The simultaneous treatment of two trauma patients in a dual-room trauma suite with an integrated movable sliding gantry CT-system requires a medical, organizational, and technical concept adapted to this special setting. Despite the oftentimes serious and life-threatening injuries, optimal diagnostic and therapeutic procedures can be guaranteed for two simultaneous trauma patients at an individual medical level in consistent quality.}, language = {en} } @article{ReppenhagenBeckerKugleretal.2023, author = {Reppenhagen, Stephan and Becker, Roland and Kugler, Andreas and John, Dominik and Kopf, Sebastian and Anetzberger, Hermann}, title = {Hand dominance is not of significance in performing fundamental arthroscopic skills simulation training tasks}, series = {Arthroscopy, Sports Medicine, and Rehabilitation}, volume = {5}, journal = {Arthroscopy, Sports Medicine, and Rehabilitation}, number = {5}, issn = {2666-061X}, doi = {10.1016/j.asmr.2023.100767}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-350432}, year = {2023}, abstract = {Purpose To compare the performance of the dominant and nondominant hand during fundamental arthroscopic simulator training. Methods Surgical trainees who participated in a 2-day simulator training course between 2021 and 2023 were classified, according to their arthroscopic experience in beginners and competents. Only right-handed individuals with complete data sets were included in the study. Ambidexterity was trained using a box trainer (Fundamentals of Arthroscopic Surgery Training, Virtamed AG, Schlieren, Switzerland).Two tasks, periscoping for learning camera guidance and triangulation for additional instrument handling, were performed 4 times with the camera in the dominant hand and then in the nondominant hand. For each task, exercise time, camera path length, and instrument path length were recorded and analyzed. Results Out of 94 participants 74 right-handed individuals (22 females, 52 males) were classified to novices (n = 43, less than 10 independently performed arthroscopies) and competents (n = 31, more than 10 independently performed arthroscopies). Competents performed significantly better than novices. No significant difference was found after changing the guiding hand for the camera from the dominant to the nondominant hand regarding the camera path length and the instrument path length. Notably, tasks were performed even faster when using the camera in the nondominant hand. Conclusions Our data demonstrate that the learned manual skills during basic arthroscopic training are quickly transferred to the contralateral side. In consequence, additional fundamental skills training for camera guidance and instrument handling of the nondominant hand are not necessary. Clinical Relevance For skillful arthroscopy, camera guidance and instrument handing must be equally mastered with both hands. It is important to understand how hand dominance may affect learning during arthroscopic simulator training.}, language = {en} } @article{KronerWeiglChuRudertetal.2023, author = {Kroner-Weigl, Niklas and Chu, Jin and Rudert, Maximilian and Alt, Volker and Shukunami, Chisa and Docheva, Denitsa}, title = {Dexamethasone is not sufficient to facilitate tenogenic differentiation of dermal fibroblasts in a 3D organoid model}, series = {Biomedicines}, volume = {11}, journal = {Biomedicines}, number = {3}, issn = {2227-9059}, doi = {10.3390/biomedicines11030772}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-311234}, year = {2023}, abstract = {Self-assembling three-dimensional organoids that do not rely on an exogenous scaffold but maintain their native cell-to-cell and cell-to-matrix interactions represent a promising model in the field of tendon tissue engineering. We have identified dermal fibroblasts (DFs) as a potential cell type for generating functional tendon-like tissue. The glucocorticoid dexamethasone (DEX) has been shown to regulate cell proliferation and facilitate differentiation towards other mesenchymal lineages. Therefore, we hypothesized that the administration of DEX could reduce excessive DF proliferation and thus, facilitate the tenogenic differentiation of DFs using a previously established 3D organoid model combined with dose-dependent application of DEX. Interestingly, the results demonstrated that DEX, in all tested concentrations, was not sufficient to notably induce the tenogenic differentiation of human DFs and DEX-treated organoids did not have clear advantages over untreated control organoids. Moreover, high concentrations of DEX exerted a negative impact on the organoid phenotype. Nevertheless, the expression profile of tendon-related genes of untreated and 10 nM DEX-treated DF organoids was largely comparable to organoids formed by tendon-derived cells, which is encouraging for further investigations on utilizing DFs for tendon tissue engineering.}, language = {en} }