10 research outputs found

    Clinical and cytogenetic characterization of tumors of the pineal region

    No full text
    Raumforderungen der PR haben ihren Ursprung zum einen in den pinealen Geweben und zum anderen in den heterogenen Strukturen des ZNS. Aufgrund ihrer anatomischen Lage im Bereich der zirkumventrikulären GP und des Hirnstammes bedeuten sie im fortgeschrittenen Stadium für die Patienten eine massiv eingeschränkte Lebensqualität bei zunehmend schlechter Prognose. Die Heterogenität dieser Tumoren stellt die Medizin jedoch vor eine große diagnostische und therapeutische Herausforderung. Entscheidend für eine optimale Therapie ist eine eindeutige Charakterisierung dieser Raumforderungen. In dieser Arbeit ist es erstmals gelungen, neben pineal-parenchymalen Raumforderungen und Keimzelltumoren der PR, pilozytische Astrozytome, einen solid-fibrösen und einen neuroendokrinen Tumor der PR molekularzytogenetisch zu charakterisieren. Die Karzinogenese der Raumforderungen der PR ist nicht abschließend geklärt. Von Tumoren, die einer histologischen Zellpopulation entsprächen, wären in Regelhaftigkeit identische genetische Veränderungen zu erwarten. Die Analysen in dieser Arbeit zeigen zum einen übereinstimmende molekularzytogenetische Veränderungen der Chromosomen 7, 9, 12 und 17 mit zuvor beschriebenen Tumoren der PR. Zudem konnte erstmals eine Vielzahl neuer chromosomaler Veränderungen beschrieben werden. Diese molekulargenetische Heterogenität stellt die aktuelle Zuordnung der Raumforderungen der PR nicht in Frage, unterstreicht jedoch, dass eine weitere histologische Charakterisierung notwendig ist, um Subgruppen zu identifizieren. Sie zeigt, dass klassische Konzepte der Tumorigenese die molekularzytogenetische Heterogenität dieser Tumoren nur unzureichend beschreiben und durch progressivere Tumormodelle ergänzt werden müssen (Berger et al. 2011). Tumoren und Raumforderungen der PR entsprechen im Kindesalter 3-8% und im Erwachsenenalter weniger als 1% aller intrazerebralen Raumforderungen (Edwards et al. 1988; Regis et al. 1996; Rickert et al. 2001), so dass Untersuchungen größerer Patienten-kollektive über einen längeren Zeitraum schwierig sind. Die molekular¬zytogenetische Zuordnung der in dieser Arbeit untersuchten Raumforderungen unterstützt und ergänzt die Charakterisierung der Tumorentitäten. Auch wenn nur eine geringe Tumoranzahl über einen längeren Zeitraum untersucht werden konnte, so ist anzunehmen, dass es möglich sein wird, einzelnen histologischen Entitäten ein zytogenetisches Muster zuzuordnen, wenn größere Tumorkollektive der PR untersucht werden. So kann die Diagnostik erweitert und eine prognostische Bedeutung zum Wohle der Patienten erlangt werden

    Distributed Cognitive Expert Systems in Cancer Data Analytics: A Decision Support System for Oral and Maxillofacial Surgery

    No full text
    Although researchers have uncovered potential positive impacts of digital technologies in healthcare and medical centers have been increasingly making use of technology to digitally store their data, the use of healthcare analytics in clinical practice remains limited. In particular, the application of machine learning (ML) approaches, although holding the potential of providing valuable insights, is mainly restricted to descriptive ML, due to the approximate nature of ML, the impact of inaccuracies, and the perceived potential additional efforts in clinical workflows. Taking into account these barriers to healthcare analytics adoption, in this multidisciplinary study, we obtained and jointly analyzed cancer data on 799 cases of cranio-maxillofacial and oral-maxillofacial surgery. We developed a real-time decision support system that predicts optimal treatments and communicates its prediction confidence along with patient attributes that are significant to decision making, thereby providing potentials simultaneously for improving quality of care and for increasing process efficiency for physicians

    Removable thermoplastic appliances modified by incisal cuts show altered biomechanical properties during tipping of a maxillary central incisor

    No full text
    Abstract Background The present study aimed to evaluate the force delivery of removable thermoplastic appliances (RTAs), modified by different sized incisal cuts, during tipping of a maxillary central incisor in palatal and vestibular direction. Methods Forty-five RTAs from three different materials (Biolon®, Erkodur®, Ideal Clear®) of the same thickness (1 mm) were used. Analysis was performed on a separated maxillary central incisor which was part of a resin model with a complete dentition. In 15 RTAs, of different material, a cut was inserted at the incisal edge of tooth 11. In 15 other appliances, the cut was extended to teeth 12 and 21. Fifteen aligners remained uncut. The experimental tooth was tipped starting from the zero position in 0.05° steps to a maximal deflection of ± 0.42° of the incisal edge in vestibular and palatal direction, after positioning the RTA onto the model. Results The horizontal (Fx) and the vertical (Fz) force components were decreased by approximately half with increasing cut size. Fz values changed during palatal tipping from a weak intrusive force, for aligners without cut, to an extrusive force with increasing cut size. Compared to both other materials used (Erkodur® and Ideal Clear®), the Biolon® aligners showed significantly higher Fx and Fz values (p < 0.0001, respectively). Conclusions RTAs modified by different sized incisal cuts show altered biomechanical properties and an inversion of the vertical force component, during tipping of a maxillary central incisor

    Murine mesenchymal progenitor cells from different tissues differentiated <it>via </it>mesenchymal microspheres into the mesodermal direction

    No full text
    Abstract Background Because specific marker molecules for phenotypical identification of mesenchymal stem and progenitor cells are missing, the assessment of the in vitro-differentiation capacity is a prerequisite to characterize these cells. However, classical differentiation protocols are often cell-consuming and time intensive. Therefore, the establishment of novel strategies for differentiation is one topic of current efforts in stem cell biology. The goal of this study was to demonstrate the practicability of a new differentiation test using plastic adherent cell isolates from different tissues. Results We introduced the mesenchymal microsphere method as a feasible time- and cell saving screening method to analyse multilineage differentiation properties of adult progenitor cells in a three-dimensional system. For this purpose we isolated, characterized and analyzed new sources of adult murine mesenchymal progenitor cells from perirenal adipose tissue and mediastinal stromal tissue in comparison to bone marrow progenitor cells. The proliferation capacity of the cells was demonstrated by determination of the daily doubling index. Although the flow cytometry analysis of undifferentiated cells revealed differences in the expression of CD marker molecules, all isolates have the capacity for multilineage differentiation following the mesenchymal microsphere protocol as well as the classical "micro mass body" protocol for chondrogenic and the monolayer cultivation protocol for osteogenic and adipogenic differentiation. Differentiation was characterized using histochemical and immunhistochemical staining as well as RT-PCR. Conclusions We were able to show that the mesenchymal microsphere method is an efficient test system for chondro-, osteo- and adipogenic differentiation of adult progenitor cells. The advantage of this system in comparison to classical protocols is that approximately 7 times lower cell numbers are necessary. Since classical culture procedures are time intensive because high cell numbers have to be obtained, the new differentiation method may also save cells and time in future clinical applications using human mesenchymal stromal cells.</p

    Additional file 1 of Accuracy of intraoral real-time navigation versus static, CAD/CAM-manufactured pilot drilling guides in dental implant surgery: an in vitro study

    No full text
    Additional file 1: Fig. S1. A) Schematic illustration of spatial offsets from implant planning. Analysis shows deviations in drilling depth, oro-vestibular as well as mesio-distal direction and angulation. B) Section of the Treatment Evaluation Tool in coDiagnostix®. Planning is shown in blue. Red shows the actual implant position. C) Mandible model used for the in vitro testing with pilot drilling guide in situ. D) DENACAM system used for the in vitro testing. E) Major findings in absolute numbers

    Accelerating the Front End of Medicine: Three Digital Use Cases and HCI Implications

    Get PDF
    Digital applications in health care are a concurrent research and management question, where implementation experiences are a core field of information systems research. It also contributes to fighting pandemic crises like COVID-19 because contactless information flow and speed of diagnostics are improved. This paper presents three digital application case studies from emergency medicine, administration management, and cancer diagnosis with AI support from the University Medical Centers of M&uuml;nster and G&ouml;ttingen in Germany. All cases highlight the potential of digitalization to increase speed and efficiency within the front end of medicine as the crucial phase before patient treatment starts. General challenges for health care project implementations and human-computer interaction (HCI) concepts in health care are derived and discussed, including the importance of specific processes together with user analysis and adaption. A derived concept for HCI includes the criteria speed, accuracy, modularity, and individuality to achieve sustainable improvements within the front end of medicine
    corecore