University of Düsseldorf

About: University of Düsseldorf is a education organization based out in Düsseldorf, Germany. It is known for research contribution in the topics: Population & Transplantation. The organization has 25225 authors who have published 49155 publications receiving 1946434 citations.

Reactive astrocyte nomenclature, definitions, and future directions

Abstract: Reactive astrocytes are astrocytes undergoing morphological, molecular, and functional remodeling in response to injury, disease, or infection of the CNS. Although this remodeling was first described over a century ago, uncertainties and controversies remain regarding the contribution of reactive astrocytes to CNS diseases, repair, and aging. It is also unclear whether fixed categories of reactive astrocytes exist and, if so, how to identify them. We point out the shortcomings of binary divisions of reactive astrocytes into good-vs-bad, neurotoxic-vs-neuroprotective or A1-vs-A2. We advocate, instead, that research on reactive astrocytes include assessment of multiple molecular and functional parameters-preferably in vivo-plus multivariate statistics and determination of impact on pathological hallmarks in relevant models. These guidelines may spur the discovery of astrocyte-based biomarkers as well as astrocyte-targeting therapies that abrogate detrimental actions of reactive astrocytes, potentiate their neuro- and glioprotective actions, and restore or augment their homeostatic, modulatory, and defensive functions.

Motifs in Brain Networks

Abstract: Complex brains have evolved a highly efficient network architecture whose structural connectivity is capable of generating a large repertoire of functional states. We detect characteristic network building blocks (structural and functional motifs) in neuroanatomical data sets and identify a small set of structural motifs that occur in significantly increased numbers. Our analysis suggests the hypothesis that brain networks maximize both the number and the diversity of functional motifs, while the repertoire of structural motifs remains small. Using functional motif number as a cost function in an optimization algorithm, we obtain network topologies that resemble real brain networks across a broad spectrum of structural measures, including small-world attributes. These results are consistent with the hypothesis that highly evolved neural architectures are organized to maximize functional repertoires and to support highly efficient integration of information.

Dimensional ridge alterations following tooth extraction. An experimental study in the dog

Abstract: The aim of the present study was to histologically evaluate extraction wound healing after socket preservation using a beta-TCP root taper.Ten dogs were used in the study. Immediately following careful extraction of the first premolar of the lower jaw the extraction sockets were filled using a chair-side thermically formed polylactide-linked root taper (RT). To avoid contamination, a further polylactide barrier covered the crestal surface of the taper. Untreated extraction sites of the opposite side served as control. After three and six months of healing, the animals were sacrified and dissected blocks were prepared for histomorphometrical analysis. Following parameters were evaluated: difference between lingual and buccal bone height, lingual and buccal alveolar wall and total bone width 1, 3 and 5mm underneath the top of the respective crest. During the entire study period healing was uneventful for all animals. Histological analysis of three months specimens revealed a definable area of minor mineralized bone within the former extraction sockets in both RT and control group. In the test group small areas of material organized by connective tissue but no remnants of the bone substitute material could be observed. After six months the borderline between new and pre-existing bone had disappeared. Histomorphometric analysis revealed no statistically significant differences between test and control group after three or six months (p>0.05, paired T-test). Within the limits of the present study it was concluded that the application of polylactide-stabilized RT does not improve the dimensional ridge alterations after tooth extraction.