Der Beitrag von GFAP zur Pathogenese des Sehnervenschadens beim Glaukom - Etablierung einer Methode zur Laserdissektion der murinen glialen Lamina

Beim primären Offenwinkelglaukom (POWG) führt ein zu hoher intraokulärer Druck (IOD) des Bulbus zur Schädigung der Axone der retinalen Ganglienzellen im Bereich der Lamina cribrosa, wo die Axone im N. opticus den Bulbus verlassen. Vermutlich erhöht der IOD die mechanische Belastung der Axone, was beim POWG dann nicht mehr kompensiert werden kann. In der Lamina cribrosa ordnen sich die Axone zu Bündeln an, die von Astrozyten umhüllt werden. Diese zeigen den Phänotyp von fibrillären Astrozyten mit einem umfangreichen Zytoskelett aus Intermediärfilamenten, die hauptsächlich aus Glial Fibrillary Acidic Protein (GFAP) bestehen. Im Mausauge entspricht der Lamina cribrosa die gliale Lamina, ein Teil des N. opticus mit einem Durchmesser von in etwa 100 µm und eine Länge von 50 µm. Bisherige Befunde der Arbeitsgruppe zeigen, dass Mäuse mit einer gentechnisch induzierten Defizienz von GFAP auch unter normalen Bedingungen kontinuierlich Axone des Sehnervens verlieren. Um mehr Informationen über die molekularen Veränderungen des glialen Lamina bei GFAP-Defizienz der Maus zu erhalten, wäre eine Bestimmung der Gesamtheit der Proteine (Proteom) der glialen Lamina hilfreich. Dies ist aber auf Grund der geringen Größe des Gewebes am Mausauge technisch sehr anspruchsvoll. Ziel der vorliegenden Arbeit war es daher zu untersuchen, ob es technisch überhaupt möglich ist ein Protokoll zu entwickeln, das die spezifische Isolierung der glialen Lamina der Maus mit der Methode des Laser Micro-Dissection Pressure Catapulting (LMPC) erlaubt, und zwar mit einer Proteinmenge und -qualität, die eine massenspektroskopische Bestimmung des Proteoms ermöglicht. In der vorliegenden Arbeit konnte gezeigt werden, dass dies möglich ist, wenn dazu die Parameter Cut: 75; LPC: 97 der LMPC zur Anwendung kommen. Für jeden Bulbus müssen dann mindestens 6-10 Gewebeschnitte gesammelt werden. Für die daran anschließende Proteomanalyse sind jeweils zwei Proben von GFAP-defizienten und Wildtyp-Mäusen notwendig. Jede Probe beinhaltet dann Dissektionsmaterial aus vier enukleierten Augen, somit mindestens 24 Gefrierschnitten. Erste vorläufige Daten der Proteomanalyse zeigen, dass das Intermediärfilament Vimentin, als weiteres Intermediärfilament, bei den GFAP-defizienten Mäusen vermehrt nachweisbar ist, um vermutlich den Verlust an GFAP zu kompensieren. Fibrillin-1, F- Actin, Caveolin-1 und Kollagen-alpha-1(III) sind dagegen verringert bzw. in kaum nachweisbaren Mengen vorhanden. Insgesamt ermöglichen die Ergebnisse der vorliegenden Arbeit eine umfassende Analyse des Proteoms der glialen Lamina der Maus

Workforce Demand Assessment to Shape Future GI-Education – First Results of a Survey

Ponencias, comunicaciones y pósters presentados en el 17th AGILE Conference on Geographic Information Science "Connecting a Digital Europe through Location and Place", celebrado en la Universitat Jaume I del 3 al 6 de junio de 2014.Geographic Information Science & Technology (GIS&T) is constantly evolving in scientific and technological terms. In 2006 the GIS&T Body of Knowledge (BoK) initiative has provided a domain inventory that serves as a structured basis for curriculum development. The content and structure of the BoK are currently undergoing revision. One of the projects addressing an update of the BoK is the project Geographic Information: Need to Know. In this project an assessment of current and future workforce demand and educational supply in the geographic information (GI) domain provide the basis for revising the BoK. This article reports on first results from a survey regarding GI workforce demand in Europe. People working in the GIS&T domain were asked to rate BoK knowledge areas related to their relevance in a professional working context. These ratings are differentiated by types of organizations and educational backgrounds of respondents. The report is rounded off with an outlook to the results on future competences identified by respondents

Bank capital regulation with random audits

We consider a model of optimal bank closure rules (cum capital replenishment by banks), with Poisson-distributed audits of the bank's asset value by the regulator, with the goal of eliminating (ameliorating) the incentives of levered bank shareholders/managers to take excessive risks in their choice of underlying assets. The roles of (tax or other) subsidies on deposit interest payments by the bank, and of the auditing frequency are examined

Spatial Modelling of Solar energy Potential in Kenya

Solar energy is one of the readily available renewable energy resources in the developing countries within the tropical region. Kenya is one of the countries which receive an average of approximately 6.5 sunshine hours in a single day throughout the year. However, there is slow adoption of solar energy resources in the country due to limited information on the spatial variability solar energy potential. This study aims at assessing the potential of photovoltaic solar energy in Kenya. The factors that influence incident solar radiation which were considered in this task included atmospheric transmissivity and topography. The influence of atmospheric transmissivity was factored in by modelling monthly transmissivity factors from a combination of cloud cover, diffuse ratios and the effect of altitude. The contribution of topography was included by applying hemispherical viewshed analysis to determine the amount of incident global radiation on the surface based on the orientation of the terrain. GIS concepts were used to integrate the spatial datasets from different themes. The results showed that, about 70% of the land area in Kenya has the potential of receiving approximately 5kWh/m2/day throughout the year. In outline, this work successfully assessed the spatio-temporal variability in the characteristics of solar energy potential in Kenya and can be used as a basis for policy support in the country

Berichte

ctn - Diözesan-Fernsehen in ChikagoChristliche Kommunikationskonferenz in MalawiSalzburger "Seminar '75": Christliche Botschaft in säkularisierten MedienVon der Eigeninitiative zur Gemeinschaftsaufgabe: 25 Jahre Arbeit der Christlichen Presse AkademiePublizistik und Erwachsenenbildung: Erfahrungsbericht aus der Bensberger Thomas-Moros-Akademie"Publik-Forums" (kirchen-)treue Leser: Ergebnisse einer Analys

Sustainable development: Understanding the least resource base

In the paper, the least resource base required to ensure isolated human habitat sustainability over a historically long period of time is discussed. Territory and energy are proposed as such basic resources. The analysis of isolated societies of Tasmania, the Chatham Islands, and North Sentinel Island concludes that habitat can exist long and sustainably in a local area of at least 30 square kilometres in a mode of inherent safety, without the use of artificial technologies. This conclusion demonstrates the possibility of sustainable development of human civilization as a sum of local communities in the context of the isolationism paradigm, an alternative to globalism's currently dominant concept. The significance of identifying the least resource base of sustainable development of isolated communities in the context of the establishment of scientific bases and settlements in remote areas of the globe, on the Moon and other planets of the solar system, and developing strategies to combat pandemics such as COVID-19, is highlighted

ISPRS International Journal of Geo-Information / Extraction of terraces on the loess plateau from high-resolution DEMs and imagery utilizing object-based image analysis

Terraces are typical artificial landforms on the Loess Plateau, with ecological functions in water and soil conservation, agricultural production, and biodiversity. Recording the spatial distribution of terraces is the basis of monitoring their extent and understanding their ecological effects. The current terrace extraction method mainly relies on high-resolution imagery, but its accuracy is limited due to vegetation coverage distorting the features of terraces in imagery. High-resolution topographic data reflecting the morphology of true terrace surfaces are needed. Terraces extraction on the Loess Plateau is challenging because of the complex terrain and diverse vegetation after the implementation of “vegetation recovery”. This study presents an automatic method of extracting terraces based on 1 m resolution digital elevation models (DEMs) and 0.3 m resolution Worldview-3 imagery as auxiliary information used for object-based image analysis (OBIA). A multi-resolution segmentation method was used where slope, positive and negative terrain index (PN), accumulative curvature slope (AC), and slope of slope (SOS) were determined as input layers for image segmentation by correlation analysis and Sheffield entropy method. The main classification features based on DEMs were chosen from the terrain features derived from terrain factors and texture features by gray-level co-occurrence matrix (GLCM) analysis; subsequently, these features were determined by the importance analysis on classification and regression tree (CART) analysis. Extraction rules based on DEMs were generated from the classification features with a total classification accuracy of 89.96%. The red band and near-infrared band of images were used to exclude construction land, which is easily confused with small-size terraces. As a result, the total classification accuracy was increased to 94%. The proposed method ensures comprehensive consideration of terrain, texture, shape, and spectrum characteristics, demonstrating huge potential in hilly-gully loess region with similarly complex terrain and diverse vegetation covers.(VLID)219512

A versatile optode system for oxygen, carbon dioxide, and pH measurements in seawater with integrated battery and logger

Herein, we present a small and versatile optode system with integrated battery and logger for monitoring of O-2, pH, and pCO(2) in seawater. Three sensing materials designed for seawater measurements are optimized with respect to dynamic measurement range and long-term stability. The spectral properties of the sensing materials were tailored to be compatible with a commercially available laboratory oxygen logger that was fitted into a pressure housing. Interchangeable sensor caps with appropriate "sensing chemistry" are conveniently attached to the end of the optical fiber. This approach allows using the same instrument for multiple analytes, which offers great flexibility and minimizes hardware costs. Applications of the new optode system were demonstrated by recording depth profiles for the three parameters during a research cruise in the Baltic Sea and by measuring surface water transects of pH. The optode was furthermore used to monitor the concentration of dissolved oxygen in a seagrass meadow in the Limfjord, Denmark, and sensor packages consisting of pO(2), pH, and pCO(2) were deployed in the harbors of Kiel, Germany, and Southampton, England, for 6 d. The measurements revealed that the system can resolve typical patterns in seawater chemistry related to spatial heterogeneities as well as temporal changes caused by biological and tidal activity

IDO1 + Paneth cells promote immune escape of colorectal cancer

Abstract: Tumors have evolved mechanisms to escape anti-tumor immunosurveillance. They limit humoral and cellular immune activities in the stroma and render tumors resistant to immunotherapy. Sensitizing tumor cells to immune attack is an important strategy to revert immunosuppression. However, the underlying mechanisms of immune escape are still poorly understood. Here we discover Indoleamine-2,3-dioxygenase-1 (IDO1)+ Paneth cells in the stem cell niche of intestinal crypts and tumors, which promoted immune escape of colorectal cancer (CRC). Ido1 expression in Paneth cells was strictly Stat1 dependent. Loss of IDO1+ Paneth cells in murine intestinal adenomas with tumor cell-specific Stat1 deletion had profound effects on the intratumoral immune cell composition. Patient samples and TCGA expression data suggested corresponding cells in human colorectal tumors. Thus, our data uncovered an immune escape mechanism of CRC and identify IDO1+ Paneth cells as a target for immunotherapy

IDO1 + Paneth cells promote immune escape of colorectal cancer

Abstract: Tumors have evolved mechanisms to escape anti-tumor immunosurveillance. They limit humoral and cellular immune activities in the stroma and render tumors resistant to immunotherapy. Sensitizing tumor cells to immune attack is an important strategy to revert immunosuppression. However, the underlying mechanisms of immune escape are still poorly understood. Here we discover Indoleamine-2,3-dioxygenase-1 (IDO1)+ Paneth cells in the stem cell niche of intestinal crypts and tumors, which promoted immune escape of colorectal cancer (CRC). Ido1 expression in Paneth cells was strictly Stat1 dependent. Loss of IDO1+ Paneth cells in murine intestinal adenomas with tumor cell-specific Stat1 deletion had profound effects on the intratumoral immune cell composition. Patient samples and TCGA expression data suggested corresponding cells in human colorectal tumors. Thus, our data uncovered an immune escape mechanism of CRC and identify IDO1+ Paneth cells as a target for immunotherapy