@article{HettichSchierjottEppleetal.2019,
  author    = {Hettich, Georg and Schierjott, Ronja A. and Epple, Matthias and Gbureck, Uwe and Heinemann, Sascha and Mozaffari-Jovein, Hadi and Grupp, Thomas M.},
  title     = {Calcium phosphate bone graft substitutes with high mechanical load capacity and high degree of interconnecting porosity},
  series = {Materials},
  volume    = {12},
  journal   = {Materials},
  number    = {21},
  issn      = {1996-1944},
  doi       = {10.3390/ma12213471},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-193233},
  pages     = {3471},
  year      = {2019},
  abstract  = {Bone graft substitutes in orthopedic applications have to fulfill various demanding requirements. Most calcium phosphate (CaP) bone graft substitutes are highly porous to achieve bone regeneration, but typically lack mechanical stability. This study presents a novel approach, in which a scaffold structure with appropriate properties for bone regeneration emerges from the space between specifically shaped granules. The granule types were tetrapods (TEPO) and pyramids (PYRA), which were compared to porous CaP granules (CALC) and morselized bone chips (BC). Bulk materials of the granules were mechanically loaded with a peak pressure of 4 MP; i.e., comparable to the load occurring behind an acetabular cup. Mechanical loading reduced the volume of CALC and BC considerably (89\% and 85\%, respectively), indicating a collapse of the macroporous structure. Volumes of TEPO and PYRA remained almost constant (94\% and 98\%, respectively). After loading, the porosity was highest for BC (46\%), lowest for CALC (25\%) and comparable for TEPO and PYRA (37\%). The pore spaces of TEPO and PYRA were highly interconnected in a way that a virtual object with a diameter of 150 µm could access 34\% of the TEPO volume and 36\% of the PYRA volume. This study shows that a bulk of dense CaP granules in form of tetrapods and pyramids can create a scaffold structure with load capacities suitable for the regeneration of an acetabular bone defect},
  language  = {en}
}
@article{PlumSteinbachAttemsetal.2016,
  author    = {Plum, Sarah and Steinbach, Simone and Attems, Johannes and Keers, Sharon and Riederer, Peter and Gerlach, Manfred and May, Caroline and Marcus, Katrin},
  title     = {Proteomic characterization of neuromelanin granules isolated from human substantia nigra by laser-microdissection},
  series = {Scientific Reports},
  volume    = {6},
  journal   = {Scientific Reports},
  number    = {37139},
  doi       = {10.1038/srep37139},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167507},
  year      = {2016},
  abstract  = {Neuromelanin is a complex polymer pigment found primarily in the dopaminergic neurons of human substantia nigra. Neuromelanin pigment is stored in granules including a protein matrix and lipid droplets. Neuromelanin granules are yet only partially characterised regarding their structure and function. To clarify the exact function of neuromelanin granules in humans, their enrichment and in-depth characterization from human substantia nigra is necessary. Previously published global proteome studies of neuromelanin granules in human substantia nigra required high tissue amounts. Due to the limited availability of human brain tissue we established a new method based on laser microdissection combined with mass spectrometry for the isolation and analysis of neuromelanin granules. With this method it is possible for the first time to isolate a sufficient amount of neuromelanin granules for global proteomics analysis from ten 10 μm tissue sections. In total 1,000 proteins were identified associated with neuromelanin granules. More than 68\% of those proteins were also identified in previously performed studies. Our results confirm and further extend previously described findings, supporting the connection of neuromelanin granules to iron homeostasis and lysosomes or endosomes. Hence, this method is suitable for the donor specific enrichment and proteomic analysis of neuromelanin granules.},
  language  = {en}
}