The First Provenance Challenge

The first Provenance Challenge was set up in order to provide a forum for the community to help understand the capabilities of different provenance systems and the expressiveness of their provenance representations. To this end, a Functional Magnetic Resonance Imaging workflow was defined, which participants had to either simulate or run in order to produce some provenance representation, from which a set of identified queries had to be implemented and executed. Sixteen teams responded to the challenge, and submitted their inputs. In this paper, we present the challenge workflow and queries, and summarise the participants contributions

Complex morphology and functional dynamics of vital murine intestinal mucosa revealed by autofluorescence 2-photon microscopy

The mucosa of the gastrointestinal tract is a dynamic tissue composed of numerous cell types with complex cellular functions. Study of the vital intestinal mucosa has been hampered by lack of suitable model systems. We here present a novel animal model that enables highly resolved three-dimensional imaging of the vital murine intestine in anaesthetized mice. Using intravital autofluorescence 2-photon (A2P) microscopy we studied the choreographed interactions of enterocytes, goblet cells, enteroendocrine cells and brush cells with other cellular constituents of the small intestinal mucosa over several hours at a subcellular resolution and in three dimensions. Vigorously moving lymphoid cells and their interaction with constituent parts of the lamina propria were examined and quantitatively analyzed. Nuclear and lectin staining permitted simultaneous characterization of autofluorescence and admitted dyes and yielded additional spectral information that is crucial to the interpretation of the complex intestinal mucosa. This novel intravital approach provides detailed insights into the physiology of the small intestine and especially opens a new window for investigating cellular dynamics under nearly physiological conditions

Kiel ist Vorreiterin : Zero-Waste-Strategien

Auf dem Weg zu einer ressourceneffizienten Gesellschaft bedarf es richtiger Rahmenbedingungen, Informationen und Handlungsalternativen. Eine Möglichkeit, diese Voraussetzungen zu schaffen, ist ein kommunales Zero-Waste-Konzept. Zero Waste lässt sich übersetzen mit "Null Abfall, null Verschwendung" und verfolgt das Ziel, möglichst wenig Abfall zu produzieren sowie effizient und sparsam mit Ressourcen umzugehen. Ein solches Konzept wie in Kiel ist die Basis für eine Zertifizierung als Zero Waste City, eine Auszeichnung, die der europäische Verein Zero Waste Europe vergibt. 2007 wurde die italienische Gemeinde Capannori zur ersten Zero Waste City in Europa erklärt, seitdem sind knapp 400 europäische Gemeinden dieser Bewegung gefolgt

Ice Recrystallization Kinetics in the Presence of Synthetic Antifreeze Glycoprotein Analogues Using the Framework of LSW Theory

Budke C, Heggemann C, Koch M, Sewald N, Koop T. Ice Recrystallization Kinetics in the Presence of Synthetic Antifreeze Glycoprotein Analogues Using the Framework of LSW Theory. Journal of Physical Chemistry B. 2009;113(9):2865-2873.The Ostwald ripening of polycrystalline ice in aqueous Sucrose Solutions was investigated experimentally. The kinetics of this ice recrystallization process was studied at temperatures between -6 and -10 degrees C and varying ice volume fractions. Using the theory of Lifshitz, Slyozov, and Wagner (LSW), the diffusion-limited rate constant for ice recrystallization was determined. Also, the effects of synthetic analogues of natural antifreeze glycoproteins (AFGP) were studied. These analogues synAFGPmi (i = 3-5) contained monosaccharide side groups instead of disaccharide side groups that occur in natural AFGP. In order to account for the inhibition effect of the synAFGPmi, we have modified classical LSW theory, allowing for the derivation of inhibition rate constants. It was found that the investigated synAFGPmi inhibit ice recrystallization at concentrations down to similar to 3 mu g mL(-1) or, equivalently, similar to 1 mu mol L-1 for the largest synAFGPmi investigated: synAFGPm5. Hence, our new method is capable of quantitatively assessing the efficiency of very similar AFGP with a sensitivity that is at least 2 orders of magnitude larger than that typical for quantitative thermal hysteresis measurements

Antifreeze glycopeptide diastereomers

Nagel L, Budke C, Dreyer A, Koop T, Sewald N. Antifreeze glycopeptide diastereomers. Beilstein Journal of Organic Chemistry. 2012;8:1657-1667.Antifreeze glycopeptides (AFGPs) are a special class of biological antifreeze agents, which possess the property to inhibit ice growth in the body fluids of arctic and antarctic fish and, thus, enable life under these harsh conditions. AFGPs are composed of 4-55 tripeptide units -Ala-Ala-Thr- glycosylated at the threonine side chains. Despite the structural homology among all the fish species, divergence regarding the composition of the amino acids occurs in peptides from natural sources. Although AFGPs were discovered in the early 1960s, the adsorption mechanism of these macromolecules to the surface of the ice crystals has not yet been fully elucidated. Two AFGP diastereomers containing different amino acid configurations were synthesized to study the influence of amino acid stereochemistry on conformation and antifreeze activity. For this purpose, peptides containing monosaccharide-substituted allo-L- and D-threonine building blocks were assembled by solid-phase peptide synthesis (SPPS). The retro-inverso AFGP analogue contained all amino acids in D-configuration, while the allo-L-diastereomer was composed of L-amino acids, like native AFGPs, with replacement of L-threonine by its allo-L-diastereomer. Both glycopeptides were analyzed regarding their conformational properties, by circular dichroism (CD), and their ability to inhibit ice recrystallization in microphysical experiments

Antifreeze glycopeptide analogs: synthesis, structural, and functional analysis

Plattner C, Nagel L, Budke C, Koop T, Sewald N. Antifreeze glycopeptide analogs: synthesis, structural, and functional analysis. AMINO ACIDS. 2009;37:41-41

Nonviral in situ green fluorescent protein labeling and culture of primary, adult human hair follicle epithelial progenitor cells

In this article we show that cloning of the human K15 promoter before a green fluorescence protein (GFP)/geneticin-resistance cassette and transfection of microdissected, organ-cultured adult human scalp hair follicles generates specific K15 promoter-driven GFP expression in their stem cell-rich bulge region. K15-GFP+ cells can be visualized in situ by GFP fluorescence and 2-photon laser scanning microscopy. Vital K15-GFP+ progenitor cells can then be selected by using the criteria of their green fluorescence, adhesion to collagen type IV and fibronectin, and geneticin resistance. Propagated K15-GFP+ cells express epithelial progenitor markers, show the expected differential gene expression profile of human bulge epithelium, and form holoclones. This application of nonretroviral, K15 promoter-driven, GFP labeling to adult human hair follicles facilitates the characterization and manipulation of human epithelial stem cells, both in situ and in vitro, and should be transferable to other complex human tissues