89 research outputs found

    Low-dose intestinal Trichuris muris infection alters the lung immune microenvironment and can suppress allergic airway inflammation

    Get PDF
    Immunological cross talk between mucosal tissues such as the intestine and the lung is poorly defined during homeostasis and disease. Here, we show that a low-dose infection with the intestinally restricted helminth parasite Trichuris muris results in the production of Th1 cell-dependent gamma interferon (IFN-γ) and myeloid cell-derived interleukin-10 (IL-10) in the lung without causing overt airway pathology. This cross-mucosal immune response in the lung inhibits the development of papain-induced allergic airway inflammation, an innate cell-mediated type 2 airway inflammatory disease. Thus, we identify convergent and nonredundant roles of adaptive and innate immunity in mediating cross-mucosal suppression of type 2 airway inflammation during low-dose helminth-induced intestinal inflammation. These results provide further insight in identifying novel intersecting immune pathways elicited by gut-to-lung mucosal cross talk

    Metal-Enhanced Fluorescence of Chlorophylls in Single Light-Harvesting Complexes

    Get PDF
    Ensemble and single-molecule spectroscopy demonstrates that both emission and absorption of peridinin−chlorophyll−protein photosynthetic antennae can be largely enhanced through plasmonic interactions. We find up to 18-fold increase of the chlorophyll fluorescence for complexes placed near a silver metal layer. This enhancement, which leaves no measurable effects on the protein structure, is observed when exciting either chlorophyll or carotenoid and is attributed predominantly to an increase of the excitation rate in the antenna. The enhancement mechanism comes from plasmon-induced amplification of electromagnetic fields inside the complex. This result is an important step toward applying plasmonic nanostructures for controlling the optical response of complex biomolecules and improving the design and functioning of artificial light-harvesting systems

    Lateral thermokarst patterns in permafrost peat plateaus in northern Norway

    Get PDF
    Subarctic peatlands underlain by permafrost contain significant amounts of organic carbon. Our ability to quantify the evolution of such permafrost landscapes in numerical models is critical for providing robust predictions of the environmental and climatic changes to come. Yet, the accuracy of large-scale predictions has so far been hampered by small-scale physical processes that create a high spatial variability of thermal surface conditions, affecting the ground thermal regime and thus permafrost degradation patterns. In this regard, a better understanding of the small-scale interplay between microtopography and lateral fluxes of heat, water and snow can be achieved by field monitoring and process-based numerical modeling. Here, we quantify the topographic changes of the Šuoššjávri peat plateau (northern Norway) over a three-year period using drone-based repeat high-resolution photogrammetry. Our results show thermokarst degradation is concentrated on the edges of the plateau, representing 77 % of observed subsidence, while most of the inner plateau surface exhibits no detectable subsidence. Based on detailed investigation of eight zones of the plateau edge, we show that this edge degradation corresponds to an annual volume change of 0.13±0.07 m3 yr−1 per meter of retreating edge (orthogonal to the retreat direction). Using the CryoGrid3 land surface model, we show that these degradation patterns can be reproduced in a modeling framework that implements lateral redistribution of snow, subsurface water and heat, as well as ground subsidence due to melting of excess ice. By performing a sensitivity test for snow depths on the plateau under steady-state climate forcing, we obtain a threshold behavior for the start of edge degradation. Small snow depth variations (from 0 to 30 cm) result in highly different degradation behavior, from stability to fast degradation. For plateau snow depths in the range of field measurements, the simulated annual volume changes are broadly in agreement with the results of the drone survey. As snow depths are clearly correlated with ground surface temperatures, our results indicate that the approach can potentially be used to simulate climate-driven dynamics of edge degradation observed at our study site and other peat plateaus worldwide. Thus, the model approach represents a first step towards simulating climate-driven landscape development through thermokarst in permafrost peatlands

    Affinity maturation generates greatly improved xyloglucan-specific carbohydrate binding modules

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Molecular evolution of carbohydrate binding modules (CBM) is a new approach for the generation of glycan-specific molecular probes. To date, the possibility of performing affinity maturation on CBM has not been investigated. In this study we show that binding characteristics such as affinity can be improved for CBM generated from the CBM4-2 scaffold by using random mutagenesis in combination with phage display technology.</p> <p>Results</p> <p>Two modified proteins with greatly improved affinity for xyloglucan, a key polysaccharide abundant in the plant kingdom crucial for providing plant support, were generated. Both improved modules differ from other existing xyloglucan probes by binding to galactose-decorated subunits of xyloglucan. The usefulness of the evolved binders was verified by staining of plant sections, where they performed better than the xyloglucan-binding module from which they had been derived. They discriminated non-fucosylated from fucosylated xyloglucan as shown by their ability to stain only the endosperm, rich in non-fucosylated xyloglucan, but not the integument rich in fucosylated xyloglucan, on tamarind seed sections.</p> <p>Conclusion</p> <p>We conclude that affinity maturation of CBM selected from molecular libraries based on the CBM4-2 scaffold is possible and has the potential to generate new analytical tools for detection of plant carbohydrates.</p

    Gesellschaftliche Akzeptanzfragen bei der Umsetzung von Wasserstofftechnologien

    Get PDF
    Die Bundesrepublik Deutschland hat sich zum Ziel gesetzt, bis 2045 klimaneutral zu werden. Das kann nur funktionieren, wenn fossile Rohstoffe durch erneuerbare Energien ersetzt werden - insbesondere in den Bereichen Industrie und Verkehr. Ein wesentlicher Baustein in diesem Transformationsprozess ist die Errichtung einer Wasserstoffwirtschaft, innerhalb derer Strom aus erneuerbaren Energien in grünen Wasserstoff umgewandelt und dieser als Energieträger vor allem in den Bereichen Industrie und Verkehr angewendet wird

    Single-crystalline YIG nanoflakes with uniaxial in-plane anisotropy and diverse crystallographic orientations

    Full text link
    We study Y3Fe5O12 (YIG) nanoflakes that we produce via mechanical cleaving and exfoliation of YIG single crystals. By characterizing their structural and magnetic properties, we find that these YIG nanoflakes have surfaces oriented along unusual crystallographic axes and uniaxial in-plane magnetic anisotropy due to their shape, both of which are not commonly available in YIG thin films. These physical properties, combined with the possibility of picking up the YIG nanoflakes and stacking them onto nanoflakes of other van der Waals materials or pre-patterned electrodes or waveguides, open unexplored possibilities for magnonics and for the realization of novel YIG-based heterostructures and devices.Comment: 13 pages, 4 figure

    Loss of vascular CD34 results in increased sensitivity to lung injury

    Get PDF
    Survival during lung injury requires a coordinated program of damage limitation and rapid repair. CD34 is a cell surface sialomucin expressed by epithelial, vascular and stromal cells that promotes cell adhesion, coordinates inflammatory cell recruitment, and drives angiogenesis. To test whether CD34 also orchestrates pulmonary damage and repair, we induced acute lung injury in wild type (WT) and Cd34-/- mice by bleomycin (BLM) administration. We found that Cd34-/- mice displayed severe weight loss and early mortality compared to WT controls. Despite equivalent early airway inflammation to WT mice, CD34-deficient animals developed interstitial edema and endothelial delamination, suggesting impaired endothelial function. Chimeric Cd34-/- mice reconstituted with WT hematopoietic cells exhibited early mortality compared to WT mice reconstituted with Cd34-/- cells, supporting an endothelial defect. CD34-deficient mice were also more sensitive to lung damage caused by influenza infection, showing greater weight loss and more extensive pulmonary remodeling. Together our data suggest that CD34 plays an essential role in maintaining vascular integrity in the lung in response to chemical- and infection-induced, tissue damage
    corecore