@article{BotheDeubelHesseetal.2019,
  author    = {Bothe, Friederike and Deubel, Anne-Kathrin and Hesse, Eliane and Lotz, Benedict and Groll, J{\"u}rgen and Werner, Carsten and Richter, Wiltrud and Hagmann, Sebastien},
  title     = {Treatment of focal cartilage defects in minipigs with zonal chondrocyte/mesenchymal progenitor cell constructs},
  series = {International Journal of Molecular Sciences},
  volume    = {20},
  journal   = {International Journal of Molecular Sciences},
  number    = {3},
  issn      = {1422-0067},
  doi       = {10.3390/ijms20030653},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-285118},
  year      = {2019},
  abstract  = {Despite advances in cartilage repair strategies, treatment of focal chondral lesions remains an important challenge to prevent osteoarthritis. Articular cartilage is organized into several layers and lack of zonal organization of current grafts is held responsible for insufficient biomechanical and biochemical quality of repair-tissue. The aim was to develop a zonal approach for cartilage regeneration to determine whether the outcome can be improved compared to a non-zonal strategy. Hydrogel-filled polycaprolactone (PCL)-constructs with a chondrocyte-seeded upper-layer deemed to induce hyaline cartilage and a mesenchymal stromal cell (MSC)-containing bottom-layer deemed to induce calcified cartilage were compared to chondrocyte-based non-zonal grafts in a minipig model. Grafts showed comparable hardness at implantation and did not cause visible signs of inflammation. After 6 months, X-ray microtomography (µCT)-analysis revealed significant bone-loss in both treatment groups compared to empty controls. PCL-enforcement and some hydrogel-remnants were retained in all defects, but most implants were pressed into the subchondral bone. Despite important heterogeneities, both treatments reached a significantly lower modified O'Driscoll-score compared to empty controls. Thus, PCL may have induced bone-erosion during joint loading and misplacement of grafts in vivo precluding adequate permanent orientation of zones compared to surrounding native cartilage.},
  language  = {en}
}
@article{HaiderAhmadYangetal.2021,
  author    = {Haider, Malik Salman and Ahmad, Taufiq and Yang, Mengshi and Hu, Chen and Hahn, Lukas and Stahlhut, Philipp and Groll, J{\"u}rgen and Luxenhofer, Robert},
  title     = {Tuning the thermogelation and rheology of poly(2-oxazoline)/poly(2-oxazine)s based thermosensitive hydrogels for 3D bioprinting},
  series = {Gels},
  volume    = {7},
  journal   = {Gels},
  number    = {3},
  issn      = {2310-2861},
  doi       = {10.3390/gels7030078},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-241781},
  year      = {2021},
  abstract  = {As one kind of "smart" material, thermogelling polymers find applications in biofabrication, drug delivery and regenerative medicine. In this work, we report a thermosensitive poly(2-oxazoline)/poly(2-oxazine) based diblock copolymer comprising thermosensitive/moderately hydrophobic poly(2-N-propyl-2-oxazine) (pPrOzi) and thermosensitive/moderately hydrophilic poly(2-ethyl-2-oxazoline) (pEtOx). Hydrogels were only formed when block length exceeded certain length (≈100 repeat units). The tube inversion and rheological tests showed that the material has then a reversible sol-gel transition above 25 wt.\% concentration. Rheological tests further revealed a gel strength around 3 kPa, high shear thinning property and rapid shear recovery after stress, which are highly desirable properties for extrusion based three-dimensional (3D) (bio) printing. Attributed to the rheology profile, well resolved printability and high stackability (with added laponite) was also possible. (Cryo) scanning electron microscopy exhibited a highly porous, interconnected, 3D network. The sol-state at lower temperatures (in ice bath) facilitated the homogeneous distribution of (fluorescently labelled) human adipose derived stem cells (hADSCs) in the hydrogel matrix. Post-printing live/dead assays revealed that the hADSCs encapsulated within the hydrogel remained viable (≈97\%). This thermoreversible and (bio) printable hydrogel demonstrated promising properties for use in tissue engineering applications.},
  language  = {en}
}
@phdthesis{Seifert2022,
  author    = {Seifert, Annika Kristina},
  title     = {Unidirectional freezing of soft and hard matter for biomedical applications},
  doi       = {10.25972/OPUS-27728},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-277281},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2022},
  abstract  = {A multitude of human tissues, such as bones, tendons, or muscles, are characterized by a hierarchical and highly ordered structure. In many cases, the loss of these tissues requires reconstruction using biocompatible replacement materials. In the field of bone replacement, the pore structure of the material has a crucial influence. Anisotropic porosity would have the advantage of facilitating the ingrowth of cells and newly formed blood vessels as well as the transport of nutrients. In this thesis, scaffolds with a highly ordered and anisotropic pore structure were fabricated using unidirectional freezing. Systematic investigations were carried out on biopolymer solutions (alginate and chitosan) to gain a deeper understanding of the freeze-structuring process. The knowledge gained was then applied to the development of anisotropically structured bone substitute materials. Here, the previously existing material platform for anisotropically structured calcium phosphates was extended to low-temperature phases such as calcium deficient hydroxyapatite (CDHA) or the secondary phosphates monetite and brushite. After the implantation of a biomaterial, the inevitably triggered initial immune response plays a key role in the success of a graft, with immune cells such as neutrophils or macrophages being of particular importance. In this thesis, the influence of anisotropically structured alpha-TCP and CDHA scaffolds as well as their unstructured references on human monocytes/macrophages was investigated. Macrophages produced extracellular traps (ETs) due to mineral nanoparticles formed by the binding of phosphate and calcium ions to human platelet lysate. In particular, incubation of alpha-TCP samples in lysate containing cell culture medium resulted in pronounced particle formation and enhanced release of ETs.},
  subject      = {Freezing},
  language  = {en}
}
@phdthesis{Pinzner2021,
  author    = {Pinzner, Florian},
  title     = {Vicinal and Double Chemoselective Biofunctionalization of Polyoxazolines},
  doi       = {10.25972/OPUS-22975},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229758},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2021},
  abstract  = {In this work, a toolbox was provided to create three-component polymer conjugates with a defined architecture, designed to bear different biocomponents that can interact with larger biological systems in biomacromolecular recognition experiments. The target architecture is the attachment of two biomolecule 'arms' to the alpha telechelic end point of a polymer and fixating the conjugate to the gold surface of SAW and SPR sensor chips with the polymer's other omega chain end. This specific design of a conjugate will be implemented by using a strategy to yield novel double alpha as well as omega telechelic functionalized POx and the success of all cascade reaction steps leading to the final conjugation product will be proven through affinity measurements between covalently bound mannose and ConA. All reactions were performed on a low molecular model level first and then transferred to telechelic and also side chain functionalized polymer systems.},
  subject      = {Polyoxazoline},
  language  = {en}
}