The cDNAs encoding the human bone morphogenetic proteins BMP-2 and BMP-4 in an eukaryotic expression vector were permanently transferred into the murine mesenchymal progenitor cell line C3H10T1/2. Originally, these cells are known to differentiate into myotubes, adipocytes, and chondrocytes upon the addition of azacytidine. Permanent transfection of genes encoding human BMP-2 and BMP-4 induces differentiation into the osteogenic lineage. The osteogenic differentiation potential of C3H10T1/2 cells is substantiated by histochemical and genetic analyses of marker genes typical or specific for osteogenesis, including the parathyroid hormone receptor, alkaline phosphatase, osteopontin, osteonectin, and osteocalcin. In addition to osteoblast formation, development into adipocytes and chondrocytes is also observed, suggesting that BMP-2 and BMP-4 induce differentiation into three mesenchymal lineages.

The murine homologue of the human motility-stimulating protein autotaxin (ATX) was identified as a BMP2 upregulated gene by subtractive cloning from mesenchymal progenitors C3H10T1/2 (Bächner, D., Ahrens, M., Betat, N., Schröder, D., Hoffmann. A., Lauber, J., Steinert, P., Flohe, L., Gross, G., 1998. Bmp-2 downstream targets in mesenchymal development identified by subtractive cloning from recombinant mesenchymal progenitors (C3H10T1/2). Dev. Dyn. 213, 398-411). ATX mRNA transcription is induced during BMP2 mediated osteo-/chondrogenic differentiation in vitro several orders of magnitude. To delineate a potential role for ATX in osteo-/chondrogenic development, its expression pattern during murine embryogenesis was examined in comparison with Col1a1 and Col2a1, a marker either of osteoblast, odontoblast and tendon or of chondrocyte development, respectively. Localization of murine ATX was first observed in the floor plate of the neural tube at day 9.5 of mouse embryonic development. Later, enhanced ATX expression levels were observed in proliferating subepithelial mesenchyme, during osteo-/chondrogenic and tooth development, in choroid plexus epithelium, in late kidney development, and in smooth muscles of the ductus deferens and the bladder.

A real-time audio rendering system is introduced which combines a full room-specific simulation, dynamic crosstalk cancellation, and multitrack binaural synthesis for virtual acoustical imaging. The system is applicable for any room shape (normal, long, flat, coupled), independent of the a priori assumption of a diffuse sound field. This provides the possibility of simulating indoor or outdoor spatially distributed, freely movable sources and a moving listener in virtual environments. In addition to that, near-tohead sources can be simulated by using measured near-field HRTFs. The reproduction component consists of a headphone-free reproduction by dynamic crosstalk cancellation. The focus of the project is mainly on the integration and interaction of all involved subsystems. It is demonstrated that the system is capable of real-time room simulation and reproduction and, thus, can be used as a reliable platform for further research on VR applications.

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High-dose-rate brachytherapy proved to be an effective treatment modality in locoregional recurrent head and neck cancer. In cases with persistent or residual tumor after primary radiochemotherapy a local boost with brachytherapy can improve the chance of cure of tumor disease.

Objective Cerebral magnetic resonance imaging with the magnet of the cochlear implant receiver/stimulator in place causes artifacts and hinders evaluation of intracerebral structures. The aim of this study was to evaluate the internal auditory canal and the labyrinth in a 1.5T MRI with the magnet in place. Study Design Observational study. Setting Tertiary referral center. Subjects and Methods The receiver/stimulator unit was placed and fixed onto the head of three volunteers at three different angles to the nasion–outer ear canal (90°–160°) and at three different distances from the outer ear canal (5–9 cm). T1 and T2 weighted sequences were conducted for each position. Results Excellent visibility of the internal auditory canal and the labyrinth was seen in the T2 weighted sequences with 9 cm between the magnet and the outer ear canal at every nasion–outer ear canal angle. T1 sequences showed poorer visibility of the internal auditory canal and the labyrinth. Conclusion Aftercare and visibility of intracerebral structures after cochlear implantation is becoming more important as cochlear implant indications are widened worldwide. With a distance of at least 9 cm from the outer ear canal the artifact induced by the magnet allows evaluation of the labyrinth and the internal auditory canal.