TY - JOUR A1 - Adel-Khattab, D. A1 - Giacomini, F. A1 - Gildenhaar, R. A1 - Berger, G. A1 - Gomes, Cynthia A1 - Linow, Ulf A1 - Hardt, M. A1 - Peleska, B. A1 - Günster, Jens A1 - Stiller, M. A1 - Houshmand, A. A1 - Ghaffar, K. A1 - Gamal, A. A1 - El-Mofty, M. A1 - Knabe, C. T1 - Development of a synthetic tissue engineered three- dimensional printed bioceramic-based bone graft with homogenously distributed osteoblasts and mineralizing bone matrix in vitro N2 - Over the last decade there have been increasing efforts to develop three-dimensional (3D) scaffolds for bone tissue Engineering from bioactive ceramics with 3D printing emerging as a promising technology. The overall objective of the present study was to generate a tissue engineered synthetic bone graft with homogenously distributed osteoblasts and mineralizing bone Matrix in vitro, thereby mimicking the advantageous properties of autogenous bone grafts and facilitating usage for reconstructing segmental discontinuity defects in vivo . To this end, 3D scaffolds were developed from a silica-containing calcium alkali orthophosphate, using, fi rst, a replica technique – the Schwartzwalder – Somers method – and, second, 3D printing, (i.e. rapid prototyping). The mechanical and physical scaffold properties and their potential to facilitate homogenous colonization by osteogenic cells and extracellular bone matrix formation throughout the porous scaffold architecture were examined. Osteoblastic cells were dynamically cultured for 7 days on both scaffold types with two different concentrations of 1.5 and 3 × 10⁹ cells/l. The amount of cells and bone matrix formed and osteogenic marker expression were evaluated using hard tissue histology, immunohistochemical and histomorphometric analysis. 3D-printed scaffolds (RPS) exhibited more micropores, greater compressive strength and silica release. RPS seeded with 3 × 10⁹ cells/l displayed greatest cell and extracellular Matrix formation, mineralization and osteocalcin expression. In conclusion, RPS displayed superior mechanical and biological properties and facilitated generating a tissue engineered synthetic bone graft in vitro, which mimics the advantageous properties of autogenous bone grafts, by containing homogenously distributed terminally differentiated osteoblasts and mineralizing bone matrix and therefore is suitable for subsequent in vivo implantation for regenerating segmental discontinuity bone defects. KW - Bone tissue engineering KW - Calcium alkali orthophosphate KW - Rapid prototyping KW - Scaffold KW - Mandible PY - 2017 DO - https://doi.org/10.1002/term.2362 SN - 1932-6254 SN - 1932-7005 VL - 12 IS - 1 SP - 44 EP - 58 PB - Wiley Online Library AN - OPUS4-40745 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Barthel, Mathias A1 - Fiedler, J. A1 - Giacomini, M. A1 - Moriske, H.-J. A1 - Seeger, Stefan A1 - Thurner, J.-U. T1 - Partikelemissionen aus Laserdruckern - Aktueller Sachstand N2 - Partikelemissionen aus Laserdruckern sind seit längerem bekannt und wurden bislang als Feinstaubmasse bei der Prüfwertvergabe für den Blauen Engel begrenzt. Seit einigen Jahren weiß man, dass neben den Feinstaubpartikeln auch ultrafeine Partikel beim Betrieb von Laserdruckern emittiert werden. Diese Emissionen lassen sich nur eingeschränkt bis gar nicht über Nachrüstfilter am Druckgerät minimieren. Das Umweltbundesamt (UBA) hat dies zum Anlass genommen, die Prüfvorgaben für den Blauen Engel im Hinblick auf die Erfassung ultrafeiner Partikel anzupassen und zu verschärfen. UBA hat hierzu einen Forschungsauftrag an die Bundesanstalt für Materialforschung und -prüfung (BAM) vergeben. Testverfahren und Prüfvorgaben sind nunmehr erarbeitet und werden im Beitrag vorgestellt. Die geänderten Prüfbedingungen sollen ab 2013 in die Prüfvorgabe eingeführt werden. Etwa drei Viertel der derzeit am Markt erhältlichen Laserdrucker werden die strengen Prüfvorgaben nicht erfüllen können. N2 - Particle emissions from laser printers are since longer time well-known. The total particulate mass (fine dust) is already limited within the Blue Angel basic criteria. For some years we know that besides fine particles (FP) also the ultrafine particle (UFP) fraction is relevant for health impact assessment. These particles are also emitted by laser printing devices. Particle filter systems, fixed outside the printing device housings, do not provide a general solution to the minimization of UFP emissions. The Federal Environment Agency of Germany (UBA) therefore decided to update the existing test procedure and its basic criteria for the Blue Angel ecolabel by considering also the number of ultra fine particles. For this project, UBA contracted the Federal Institute for Materials Research and Testing (BAM). As an outcome, the draft proposal for the extended test procedure along with particle emission limits is presented here. The changed basic criteria are to be set into force by January 2013. It is expected that approximately three-quarters of the printers currently available on the market will not meet these strict test criteria. KW - Laserdrucker KW - Blauer Engel KW - UFP KW - FP KW - Partikelemissionen PY - 2012 SN - 2190-1120 SN - 2190-1147 VL - 1 SP - 23 EP - 29 PB - BfS CY - Berlin AN - OPUS4-25922 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -