1,008 research outputs found

    Erkennung von methanogenen Archaeen durch Zellen des angeborenen Immunsystems

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    The importance of the microbiota on health and immune homeostasis is widely accepted and many studies are currently dissecting the interaction between the microbiota and our body. Archaea are present at nearly every part of the body but their contribution to health and disease is not understood. The gut-associated methanogenic archaeon Methanosphaera stadtmanae induces inflammatory responses, however, the mechanism how this archaeon is sensed by the immune system has not been evaluated. In contrast, Methanomassiliicoccus luminyensis is discussed for supplementation in humans as it has the unique metabolic capability to degrade harmful trimethylamines. This study aims (1) to elucidate the receptors, archaeal structures and signaling pathways that are engaged upon activation by M. stadtmanae and (2) to analyze immunological features of M. luminyensis to exclude excessive immune stimulation. Human innate immune cells were used to characterize cellular activation showing that M. stadtmanae is a strong activator of the innate immune system capable of inflammasome activation and induction of interferons. Knockout cell lines were generated using CRISPR/Cas9 to specifically identify TLR7 and TLR8 as key receptors. Furthermore, our data demonstrate a TLR8-dependent activation of the NLRP3 inflammasome sharing major characteristics with the LPS-induced alternative pathway. M. luminyensis on the other hand induces only a weak response probably due to its low phagocytosis rate. Moreover, M. luminyensis exhibits typical characteristics of a commensal gut inhabitant which supports its application as probiotic supplement for TMA degradation. For the first time, this work describes specific recognition of an archaeon by human immune cells on the molecular level. As some studies indicate a potential connection of M. stadtmanae to inflammatory bowel disease and lung hypersensitivity, our findings might help to understand how archaea are involved in inflammatory disease progression.Die Mikrobiota des Menschen ist wichtig fĂŒr dessen Gesundheit und hat großen Einfluss auf die Immunhomöostase. Archaeen sind auf allen Körperstellen zu finden, ihr Einfluss auf Gesundheit und Krankheit ist jedoch weitgehend unbekannt. Methanosphaera stadtmanae ist ein methanogenes Archaeon, welches inflammatorische Immunantworten auslösen kann. Der molekulare Mechanismus, wie M. stadtmanae vom Immunsystem erkannt wird, ist unbekannt. Im Gegensatz dazu wird Methanomassiliicoccus luminyensis als Probiotikum diskutiert, da es schĂ€dliches Trimethylamin verstoffwechseln kann. Seine immunstimulatorische AktivitĂ€t ist jedoch unbekannt. Ziel dieser Arbeit ist es (1) die Rezeptoren, archaeellen Strukturen und Signalwege zu identifizieren, die wichtig fĂŒr die Erkennung sind und (2) die immunologischen Eigenschaften von M. luminyensis zu analysieren, um ĂŒbermĂ€ĂŸige Immunantworten auszuschließen. Humane myeloide Zellen wurden verwendet, um die durch M. stadtmanae-vermittelte Immunantwort zu untersuchen, die vor allem durch Aktivierung des Inflammasoms und Expression von Interferonen gekennzeichnet ist. Mit Hilfe von CRISPR/Cas9-generierten knockout Zelllinien konnten TLR7 und TLR8 als SchlĂŒsselrezeptoren identifiziert werden. Zudem wird eine TLR8-abhĂ€ngige Inflammasomaktivierung induziert, die Eigenschaften der LPS-abhĂ€ngigen alternativen Aktivierung aufweist. M. luminyensis löst dagegen nur schwache Immunantworten aus, wahrscheinlich aufgrund seiner geringen phagozytotischen Eigenschaften. Dieses Archaeon besitzt typische Eigenschaften eines kommensalen Darmbewohners, was fĂŒr einen Einsatz als Probiotikum spricht. Zum ersten Mal konnte auf molekularer Ebene die Erkennung eines Archaeons durch menschliche Immunzellen beschrieben werden. Da ein Zusammenhang von M. stadtmanae mit chronisch entzĂŒndlichen Darmerkrankungen und LungenhypersensitivitĂ€t vermutet wird, kann diese Arbeit dazu beitragen, die Rolle von Archaeen in entzĂŒndlichen Erkrankungen besser zu verstehen

    Testing the stability of behavioural coping style across stress contexts in the Trinidadian guppy

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    This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.1. Within-populations, individuals can vary in stress response, a multivariate phenomenon comprising neuroendocrine, physiological and behavioural traits. 2. Verbal models of individual stress ‘coping style’ have proposed that the behavioural component of this variation can be described as a single axis, with each individual’s coping style being consistent across time and stress contexts. 3. Focusing on this behavioural component of stress response, and combining repeated measures of multiple traits with a novel multivariate modelling framework, we test for the existence of coping style variation and assess its stability across contexts in the Trinidadian guppy (Poecilia reticulata). 4. Specifically, we test the following hypotheses: (i) there exists repeatable among-individual behavioural (co)variation (‘personality’) within a mild stress context consistent with a risk-averse—risk-prone continuum of behavioural coping style, (ii) there is population-level plasticity in behaviour as a function of stressor severity, (iii) there is among-individual variation in plasticity (i.e., IxE), and (iv) the presence of IxE reduces cross-context stability of behavioural coping style. 5. We found significant repeatable among-individual behavioural (co)variation in the mild stress context (open field trial), represented as an I matrix. However, I was not readily described by a simple risk-averse—risk-prone continuum as posited by the original coping style model. We also found strong evidence for population-level changes in mean behaviour with increasing stressor severity (simulated avian and piscine predation risks). 6. Single-trait analyses did show the presence of individual-by-environment interactions (IxE), as among-individual cross-context correlations were significantly less than +1. However, multi-trait analysis revealed the consequences of this plasticity variation were minimal. Specifically, we found little evidence for changes in the structure of I between mild and moderate stress contexts overall, and only minor changes between the two moderate contexts (avian versus piscine predator). 7. We show that a multivariate approach to assessing changes in among individual (co)variance across contexts can prevent the over-interpretation of statistically significant, but small, individual-by-environment effects. While behavioural flexibility enables populations (and individuals) to respond rapidly to changes in the environment, multivariate personality structure can be conserved strongly across such contexts.Funding was provided by a grant from the Biotechnology and Biological Sciences Research Council (BBSRC, grant BB/L022656/1). A.J.Y. is supported by a BBSRC David Phillips Fellowship

    Narrowing the Digital Divide: The Young Women Leaders Program HerStory Project

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    Research suggests that girls are at especial disadvantage in the field of informational technology and are less likely than boys to take courses or seek out careers in this area. The Young Women Leaders Program (YWLP), a mentoring program at the University of Virginia that pairs at-risk middle school girls with college women for a year of mentoring, developed the YWLP HerStory project to engage middle school girls in informational technology through their development of technology projects focused on psychosocial issues of importance to them. This study reviewed an early version of the YWLP HerStory’s technology curriculum and training for mentors, the revisions made to both, and evaluated the effectiveness of the revisions with a sample of 27 eighth grade girls and their mentors. Findings indicated that participating in the revised curriculum improved girls’ engagement in technology projects, including an 83% completion rate, and modifications to mentor training improved mentor’s grasp of relevant technology and confidence in teaching it to their mentees. Notably, participating eighth grade girls reported that the technology curriculum was fun and expressed an interest in further engagement in using technology platforms to tell their stories

    Konzeption und Evaluation einer Webanwendung fĂŒr die narrative Schreibkompetenzförderung heterogener Lerngruppen der 5. Jahrgangsstufe als Beispiel der Synthese von Inklusion und Digitalisierung

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    Die Konvention ĂŒber die Rechte von Menschen mit Behinderungen (United Nations, 2006) wirkte weltweit wie ein Motor fĂŒr die inklusive Entwicklung. Die Ratifizierung dieser Konvention durch Deutschland 2009 fĂŒhrte in den einzelnen BundeslĂ€ndern dazu, gravierende VerĂ€nderungen im Schulsystem anzustreben und umzusetzen. Eine gleichberechtigte Teilhabe an Bildung wirft große Herausforderungen in der zunehmend heterogenen Gesellschaft auf. Vor allem bezogen auf schulische Bildung bedeutet dies fĂŒr LehrkrĂ€fte einen umfassenden Blick auf die heterogene SchĂŒler:innenschaft und das erfolgreiche Lehren und Lernen. In diesem Beitrag wird die Konzeption einer Webanwendung, die die Förderung des narrativen Schreibens von SchĂŒler:innen in einer heterogenen Lerngruppe unterstĂŒtzt, thematisiert. Es werden in diesem Beitrag neben einer theoretischen Fundierung der Konzeption der Webanwendung, die Ergebnisse der Pilotstudie berichtet und das Vorgehen in der aktuell laufenden Hauptuntersuchung skizziert. (DIPF/Orig.

    "Der ist da völlig ausgerastet". Aggressives Verhalten von SchĂŒler:innen im Grundschulunterricht aus Lehrkraftperspektive

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    Aggressives Verhalten von SchĂŒler:innen beeintrĂ€chtigt nicht nur die sozialemotionale Entwicklung von Kindern, sondern ist oftmals auch die Ursache von Unterrichtsstörungen. Bisherigen Studien zufolge ist davon auszugehen, dass LehrkrĂ€fte insgesamt eher stark kontrollierend, wenig unterstĂŒtzend und mit negativem Affekt auf aggressives Verhalten von Kindern im Unterricht reagieren. Doch qualitative Studien, die untersuchen, welche Vorstellungen von LehrkrĂ€ften zu diesem Verhalten fĂŒhren, bleiben ein Forschungsdesiderat. Daher werden in der vorliegenden Studie Interviews von 21 GrundschullehrkrĂ€ften inhaltsanalytisch untersucht, um herauszuarbeiten, welche Vorstellungen LehrkrĂ€fte zu aggressivem Verhalten haben und wie die LehrkrĂ€fte ihr eigenes Verhalten zu Unterrichtssituationen mit aggressivem Verhalten von SchĂŒler:innen beschreiben. (DIPF/Orig.

    The long non-coding RNA LUCAT1 is a negative feedback regulator of interferon responses in humans

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    Long non-coding RNAs are important regulators of biological processes including immune responses. The immunoregulatory functions of lncRNAs have been revealed primarily in murine models with limited understanding of lncRNAs in human immune responses. Here, we identify lncRNA LUCAT1 which is upregulated in human myeloid cells stimulated with lipopolysaccharide and other innate immune stimuli. Targeted deletion of LUCAT1 in myeloid cells increases expression of type I interferon stimulated genes in response to LPS. By contrast, increased LUCAT1 expression results in a reduction of the inducible ISG response. In activated cells, LUCAT1 is enriched in the nucleus where it associates with chromatin. Further, LUCAT1 limits transcription of interferon stimulated genes by interacting with STAT1 in the nucleus. Together, our study highlights the role of the lncRNA LUCAT1 as a post-induction feedback regulator which functions to restrain the immune response in human cells

    New directions for the treatment of adrenal insufficiency

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    The following funding bodies supported this work: Biotechnology and Biological Sciences Research Council (BBSRC BB/L00267/1, to LG), Rosetrees Trust (to LG), Barts and The London Charity (417/2235, to LG), EU COFUND (PCOFUND-GA-2013-608765, to LG and GRB). IH is supported by a Medical Research Council (MRC, G0802796) PhD studentship
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