@article{SchandaKeiblHeimeletal., author = {Schanda, Jakob and Keibl, Claudia and Heimel, Patrick and Monforte, Xavier and Feichtinger, Xaver and Teuschl, Andreas and Baierl, Andreas and Muschitz, Christian and Redl, Heinz and Fialka, Christian and Mittermayr, Rainer}, title = {Zoledronic Acid Substantially Improves Bone Microarchitecture and Biomechanical Properties After Rotator Cuff Repair in a Rodent Chronic Defect Model}, series = {Am J Sports Med}, volume = {2020 Jul}, journal = {Am J Sports Med}, number = {48 (9)}, pages = {2151 -- 2160}, abstract = {Background: Bone mineral density at the humeral head is reduced in patients with chronic rotator cuff tears. Bone loss in the humeral head is associated with repair failure after rotator cuff reconstruction. Bisphosphonates (eg, zoledronic acid) increase bone mineral density. Hypothesis: Zoledronic acid improves bone mineral density of the humeral head and biomechanical properties of the enthesis after reconstruction of chronic rotator cuff tears in rats. Study design: Controlled laboratory study. Methods: A total of 32 male Sprague-Dawley rats underwent unilateral (left) supraspinatus tenotomy with delayed transosseous rotator cuff reconstruction after 3 weeks. All rats were sacrificed 8 weeks after rotator cuff repair. Animals were randomly assigned to 1 of 2 groups. At 1 day after rotator cuff reconstruction, the intervention group was treated with a single subcutaneous dose of zoledronic acid at 100 µg/kg bodyweight, and the control group received 1 mL of subcutaneous saline solution. In 12 animals of each group, micro-computed tomography scans of both shoulders were performed as well as biomechanical testing of the supraspinatus enthesis of both sides. In 4 animals of each group, histological analyses were conducted. Results: In the intervention group, bone volume fraction (bone volume/total volume [BV/TV]) of the operated side was higher at the lateral humeral head (P = .005) and the medial humeral head (P = .010) compared with the control group. Trabecular number on the operated side was higher at the lateral humeral head (P = .004) and the medial humeral head (P = .001) in the intervention group. Maximum load to failure rates on the operated side were higher in the intervention group (P < .001). Cortical thickness positively correlated with higher maximum load to failure rates in the intervention group (r = 0.69; P = .026). Histological assessment revealed increased bone formation in the intervention group. Conclusion: Single-dose therapy of zoledronic acid provided an improvement of bone microarchitecture at the humeral head as well as an increase of maximum load to failure rates after transosseous reconstruction of chronic rotator cuff lesions in rats. Clinical relevance: Zoledronic acid improves bone microarchitecture as well as biomechanical properties after reconstruction of chronic rotator cuff tears in rodents. These results need to be verified in clinical investigations.}, subject = {Tissue Engineering}, language = {en} } @article{SlezakSlezakHartingeretal., author = {Slezak, Paul and Slezak, Cyrill and Hartinger, Joachim and Teuschl, Andreas and N{\"u}rnberger, Sylvia and Redl, Heinz and Mittermayr, Rainer}, title = {A Low Cost Implantation Model in the Rat That Allows a Spatial Assessment of Angiogenesis.}, series = {Frontiers in Bioengineering and Biotechnology}, journal = {Frontiers in Bioengineering and Biotechnology}, abstract = {There is continual demand for animal models that allow a quantitative assessment of angiogenic properties of biomaterials, therapies, and pharmaceuticals. In its simplest form, this is done by subcutaneous material implantation and subsequent vessel counting which usually omits spatial data. We have refined an implantation model and paired it with a computational analytic routine which outputs not only vessel count but also vessel density, distribution, and vessel penetration depth, that relies on a centric vessel as a reference point. We have successfully validated our model by characterizing the angiogenic potential of a fibrin matrix in conjunction with recombinant human vascular endothelial growth factor (rhVEGF165). The inferior epigastric vascular pedicles of rats were sheathed with silicone tubes, which were subsequently filled with 0.2 ml of fibrin and different doses of rhVEGF165, centrically embedding the vessels. Over 4 weeks, tissue samples were harvested and subsequently immunohistologically stained and computationally analyzed. The model was able to detect variations over the angiogenic potentials of growth factor spiked fibrin matrices. Adding 20 ng of rhVEGF165 resulted in a significant increase in vasculature while 200 ng of rhVEGF165 did not improve vascular growth. Vascularized tissue volume increased during the first week and vascular density increased during the second week. Total vessel count increased significantly and exhibited a peak after 2 weeks which was followed by a resorption of vasculature by week 4. In summary, a simple implantation model to study in vivo vascularization with only a minimal workload attached was enhanced to include morphologic data of the emerging vascular tree.}, subject = {Tissue Engineering}, language = {en} } @article{BerkovitchCohenPeledetal., author = {Berkovitch, Yulia and Cohen, Talia and Peled, Eli and Schmidhammer, Robert and Hildner, Florian and Teuschl, Andreas and Wolbank, Susanne and Yelin, Dvir and Redl, Heinz and Seliktar, Dror}, title = {Hydrogel composition and laser micropatterning to regulate sciatic nerve regeneration.}, series = {Journal of Tissue Engineering and Regenerative Medicine}, journal = {Journal of Tissue Engineering and Regenerative Medicine}, pages = {1049 -- 1061}, abstract = {Treatment of peripheral nerve injuries has evolved over the past several decades to include the use of sophisticated new materials endowed with trophic and topographical cues that are essential for in vivo nerve fibre regeneration. In this research, we explored the use of an advanced design strategy for peripheral nerve repair, using biological and semi-synthetic hydrogels that enable controlled environmental stimuli to regenerate neurons and glial cells in a rat sciatic nerve resection model. The provisional nerve growth conduits were composed of either natural fibrin or adducts of synthetic polyethylene glycol and fibrinogen or gelatin. A photo-patterning technique was further applied to these 3D hydrogel biomaterials, in the form of laser-ablated microchannels, to provide contact guidance for unidirectional growth following sciatic nerve injury. We tested the regeneration capacity of subcritical nerve gap injuries in rats treated with photo-patterned materials and compared these with injuries treated with unpatterned hydrogels, either stiff or compliant. Among the factors tested were shear modulus, biological composition, and micropatterning of the materials. The microchannel guidance patterns, combined with appropriately matched degradation and stiffness properties of the material, proved most essential for the uniform tissue propagation during the nerve regeneration process.}, subject = {Tissue Engineering}, language = {en} } @incollection{HackethalSchuhHoferetal., author = {Hackethal, Johannes and Schuh, Christina and Hofer, Alexandra and Meixner, Barbara and Hennerbichler, Simone and Redl, Heinz and Teuschl, Andreas}, title = {Human Placenta Laminin-111 as a Multifunctional Protein for Tissue Engineering and Regenerative Medicine}, series = {Advances in Experimental Medicine and Biology}, booktitle = {Advances in Experimental Medicine and Biology}, publisher = {Springer}, publisher = {Fachhochschule Technikum Wien}, subject = {Biomaterial}, language = {en} } @techreport{Freistetter, author = {Freistetter, Florian}, title = {The Power of Lauf}, organization = {ORF Sendung "Science Busters"}, subject = {Bioreactor}, language = {de} } @article{SchneiderEnayatiGrasletal., author = {Schneider, Karl Heinrich and Enayati, Marjan and Grasl, Christian and Walter, Ingrid and Budinsky, Lubos and Zebic, Gabriel and Kaun, Christoph and Wagner, Anja and Kratochwill, Klaus and Redl, Heinz and Teuschl, Andreas and Podesser, Bruno K. and Bergmeister, Helga}, title = {Acellular vascular matrix grafts from human placenta chorion: Impact of ECM preservation on graft characteristics, protein composition and in vivo performance.}, series = {Biomaterials}, journal = {Biomaterials}, pages = {14 -- 26}, abstract = {Small diameter vascular grafts from human placenta, decellularized with either Triton X-100 (Triton) or SDS and crosslinked with heparin were constructed and characterized. Graft biochemical properties, residual DNA, and protein composition were evaluated to compare the effect of the two detergents on graft matrix composition and structural alterations. Biocompatibility was tested in vitro by culturing the grafts with primary human macrophages and in vivo by subcutaneous implantation of graft conduits (n = 7 per group) into the flanks of nude rats. Subsequently, graft performance was evaluated using an aortic implantation model in Sprague Dawley rats (one month, n = 14). In situ graft imaging was performed using MRI angiography. Retrieved specimens were analyzed by electromyography, scanning electron microscopy, histology and immunohistochemistry to evaluate cell migration and the degree of functional tissue remodeling. Both decellularization methods resulted in grafts of excellent biocompatibility in vitro and in vivo, with low immunogenic potential. Proteomic data revealed removal of cytoplasmic proteins with relative enrichment of ECM proteins in decelluarized specimens of both groups. Noteworthy, LC-Mass Spectrometry analysis revealed that 16 proteins were exclusively preserved in Triton decellularized specimens in comparison to SDS-treated specimens. Aortic grafts showed high patency rates, no signs of thrombus formation, aneurysms or rupture. Conduits of both groups revealed tissue-specific cell migration indicative of functional remodeling. This study strongly suggests that decellularized allogenic grafts from the human placenta have the potential to be used as vascular replacement materials. Both detergents produced grafts with low residual immunogenicity and appropriate mechanical properties. Observed differences in graft characteristics due to preservation method had no impact on successful in vivo performance in the rodent model.}, subject = {Biomaterial}, language = {en} } @article{BachmannSpitzRothbaueretal., author = {Bachmann, Barbara and Spitz, Sarah and Rothbauer, Mario and Jordan, Christian and Purtscher, Michaela and Zirath, Helene and Schuller, Patrick and Eilenberger, Christoph and Ali, Syed Faheem and M{\"u}hleder, Severin and Priglinger, Eleni and Harasek, Michael and Redl, Heinz and Holnthoner, Wolfgang and Ertl, Peter}, title = {Engineering of three-dimensional pre-vascular networks within fibrin hydrogel constructs by microfluidic control over reciprocal cell signaling}, series = {Biomicrofluidics}, journal = {Biomicrofluidics}, subject = {Microfluidic}, language = {en} }