20 research outputs found

    Selective Uptake of Pelagic Microbial Community Members by Caribbean Reef Corals

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    Coral reefs are possible sinks for microbes; however, the removal mechanisms at play are not well understood. Here, we characterize pelagic microbial groups at the CARMABI reef (Curaçao) and examine microbial consumption by three coral species: Madracis mirabilis, Porites astreoides, and Stephanocoenia intersepta. Flow cytometry analyses of water samples collected from a depth of 10 m identified 6 microbial groups: Prochlorococcus, three groups of Synechococcus, photosynthetic eukaryotes, and heterotrophic bacteria. Minimum growth rates (”) for Prochlorococcus, all Synechococcus groups, and photosynthetic eukaryotes were 0.55, 0.29, and 0.45” day-1, respectively, and suggest relatively high rates of productivity despite low nutrient conditions on the reef. During a series of 5-h incubations with reef corals performed just after sunset or prior to sunrise, reductions in the abundance of photosynthetic picoeukaryotes, Prochlorococcus and Synechococcus cells, were observed. Of the three Synechococcus groups, one decreased significantly during incubations with each coral and the other two only with M. mirabilis. Removal of carbon from the water column is based on coral consumption rates of phytoplankton and averaged between 138 ng h-1and 387 ng h-1, depending on the coral species. A lack of coral-dependent reduction in heterotrophic bacteria, differences in Synechococcus reductions, and diurnal variation in reductions of Synechococcus and Prochlorococcus, coinciding with peak cell division, point to selective feeding by corals. Our study indicates that bentho-pelagic coupling via selective grazing of microbial groups influences carbon flow and supports heterogeneity of microbial communities overlying coral reefs. Importance We identify interactions between coral grazing behavior and the growth rates and cell abundances of pelagic microbial groups found surrounding a Caribbean reef. During incubation experiments with three reef corals, reductions in microbial cell abundance differed according to coral species and suggest specific coral or microbial mechanisms are at play. Peaks in removal rates of Prochlorococcus and Synechococcus cyanobacteria appear highest during postsunset incubations and coincide with microbial cell division. Grazing rates and effort vary across coral species and picoplankton groups, possibly influencing overall microbial composition and abundance over coral reefs. For reef corals, use of such a numerically abundant source of nutrition may be advantageous, especially under environmentally stressful conditions when symbioses with dinoflagellate algae break down

    Cyanobacterial distributions along a physico-chemical gradient in the Northeastern Pacific Ocean

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    The cyanobacteria Prochlorococcus and Synechococcus are important marine primary producers. We explored their distributions and covariance along a physico-chemical gradient from coastal to open ocean waters in the Northeastern Pacific Ocean. An inter-annual pattern was delineated in the dynamic transition zone where upwelled and eastern boundary current waters mix, and two new Synechococcus clades, Eastern Pacific Clade (EPC) 1 and EPC2, were identified. By applying state-of-the-art phylogenetic analysis tools to bar-coded 16S amplicon datasets, we observed higher abundance of Prochlorococcus high-light I (HLI) and low-light I (LLI) in years when more oligotrophic water intruded farther inshore, while under stronger upwelling Synechococcus I and IV dominated. However, contributions of some cyanobacterial clades were proportionally relatively constant, e.g. Synechococcus EPC2. In addition to supporting observations that Prochlorococcus LLI thrive at higher irradiances than other LL taxa, the results suggest LLI tolerate lower temperatures than previously reported. The phylogenetic precision of our 16S rRNA gene analytical approach and depth of bar-coded sequencing also facilitated detection of clades at low abundance in unexpected places. These include Prochlorococcus at the coast and Cyanobium-related sequences offshore, although it remains unclear whether these came from resident or potentially advected cells. Our study enhances understanding of cyanobacterial distributions in an ecologically important eastern boundary system. © 2014 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd

    Severe Asthma Standard-of-Care Background Medication Reduction With Benralizumab: ANDHI in Practice Substudy

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    Background: The phase IIIb, randomized, parallel-group, placebo-controlled ANDHI double-blind (DB) study extended understanding of the efficacy of benralizumab for patients with severe eosinophilic asthma. Patients from ANDHI DB could join the 56-week ANDHI in Practice (IP) single-arm, open-label extension substudy. Objective: Assess potential for standard-of-care background medication reductions while maintaining asthma control with benralizumab. Methods: Following ANDHI DB completion, eligible adults were enrolled in ANDHI IP. After an 8-week run-in with benralizumab, there were 5 visits to potentially reduce background asthma medications for patients achieving and maintaining protocol-defined asthma control with benralizumab. Main outcome measures for non-oral corticosteroid (OCS)-dependent patients were the proportions with at least 1 background medication reduction (ie, lower inhaled corticosteroid dose, background medication discontinuation) and the number of adapted Global Initiative for Asthma (GINA) step reductions at end of treatment (EOT). Main outcomes for OCS-dependent patients were reductions in daily OCS dosage and proportion achieving OCS dosage of 5 mg or lower at EOT. Results: For non-OCS-dependent patients, 53.3% (n = 208 of 390) achieved at least 1 background medication reduction, increasing to 72.6% (n = 130 of 179) for patients who maintained protocol-defined asthma control at EOT. A total of 41.9% (n = 163 of 389) achieved at least 1 adapted GINA step reduction, increasing to 61.8% (n = 110 of 178) for patients with protocol-defined EOT asthma control. At ANDHI IP baseline, OCS dosages were 5 mg or lower for 40.4% (n = 40 of 99) of OCS-dependent patients. Of OCS-dependent patients, 50.5% (n = 50 of 99) eliminated OCS and 74.7% (n = 74 of 99) achieved dosages of 5 mg or lower at EOT. Conclusions: These findings demonstrate benralizumab's ability to improve asthma control, thereby allowing background medication reduction

    AI is a viable alternative to high throughput screening: a 318-target study

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    : High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNetÂź convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNetÂź model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery

    Cyberlindnera jadinii and Kluyveromyces lactis, two fungi used in food processes, have potential probiotic effects on gut inflammation

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    International audienceMany strains have been used and selected by the food industry for their capacities to ferment, produce flavors, or produce heterologous molecules. Very little is known about the diversity of foodborne yeasts and their potential effect on gut microbiota and gut health. We initiated a complete characterization of five strains belonging to five species with a long history of safe use in food: Cyberlindnera jadinii, Debaryomyces hansenii, Kazachstania unispora, Kluyveromyces lactis, and Pichia membra nifaciens, with a focus on their capacity to protect against gut inflammation using an in vivo dextran sodium sulfate-induced colitis model in mice. C. jadinii and K. lactis living cells showed a clear reduction in mouse sensitivity to colitis in vivo. Interestingly, we observed that C. jadinii had the capacity to survive transit in the gut, while K. lactis did not. We demonstrated that C. jadinii was unable to efficiently adhere to epithelial cells and did not survive more than 24 to 48 h in the gut. Transcriptomic analysis using NanoString technology suggested a potential role of IL-8 through Mif and Fkbp5 in the effect of C. jadinii on the immune system. Bacterial and fungal microbiota characterization showed a modification of both microbiota after C. jadinii treatment, with a significant increase in positive microorganisms and a decrease in pathobionts. Altogether, these data suggest that both C. jadinii and K. lactis strains have potential as probiotic yeast strains to fight against inflammation in the gut, but further studies are needed to understand the mechanisms by which these strains act on gut health

    Projet Plasti-nium (2021-2025) : DĂ©bris plastiques dans le continuum Terre-Mer

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    15e JournĂ©e scientifique de l'OSUNA, NANTES, FRANCE, 03-/06/2022 - 03/06/2022Le projet Plasti-nium - DĂ©bris Plastiques dans le continuum terre-mer - ambitionne d'Ă©tudier la pollution plastique de la ville jusqu'Ă  la mer et de crĂ©er une dynamique transverse et interdisciplinaire sur cette thĂ©matique au sein de la RĂ©gion des Pays de la Loire. La problĂ©matique des dĂ©bris plastiques et plus spĂ©cifiquement des microplastiques (taille < 5 mm) est aujourd'hui trĂšs mĂ©diatisĂ©e et trouve une caisse de rĂ©sonance importante dans notre sociĂ©tĂ© civile. Concomitamment, la communautĂ© scientifique dĂ©montre les impacts nĂ©gatifs gĂ©nĂ©rĂ©s par cette pollution plastique sur les Ă©cosystĂšmes. Il en rĂ©sulte aujourd'hui que les actions gouvernementales et autres actions locales et rĂ©gionales se multiplient. La rĂ©gion des Pays de la Loire, dans le cadre de la stratĂ©gie « ambition marine » de 2018, vise spĂ©cifiquement la pollution plastique, et prĂ©cise que des initiatives trĂšs concrĂštes de rĂ©duction sont dĂ©jĂ  opĂ©rationnelles ou sur le point de l'ĂȘtre. Nantes MĂ©tropole, territoire reconnu « ZĂ©ro dĂ©chet, zĂ©ro gaspillage » soutient Ă©galement des initiatives expĂ©rimentales, innovantes, contribuant Ă  un territoire zĂ©ro dĂ©chet. Évaluer la mise en oeuvre de ces actions quelle que soit leur forme - de la sensibilisation Ă  la gestion intĂ©grĂ©e et concertĂ©e au niveau d'un territoire - constitue un enjeu. Le projet Plasti-nium vise Ă  offrir un accompagnement scientifique de ces programmes, et de bien articuler l'acquisition des connaissances, leur transfert et les actions des politiques publiques. Cet accompagnement peut largement contribuer au rayonnement national et international de ces initiatives. Dans cette dĂ©marche, la finalitĂ© du projet Plasti-nium est de fournir un cadre de rĂ©flexion et d'expertise pour alimenter l'Ă©laboration et la mise en oeuvre du plan rĂ©gional de prĂ©vention et de gestion des dĂ©chets avec lequel la RĂ©gion ambitionne d'ĂȘtre un territoire leader en termes de gestion des dĂ©chets

    Projet Plasti-nium (2021-2025) : DĂ©bris plastiques dans le continuum Terre-Mer

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    15e JournĂ©e scientifique de l'OSUNA, NANTES, FRANCE, 03-/06/2022 - 03/06/2022Le projet Plasti-nium - DĂ©bris Plastiques dans le continuum terre-mer - ambitionne d'Ă©tudier la pollution plastique de la ville jusqu'Ă  la mer et de crĂ©er une dynamique transverse et interdisciplinaire sur cette thĂ©matique au sein de la RĂ©gion des Pays de la Loire. La problĂ©matique des dĂ©bris plastiques et plus spĂ©cifiquement des microplastiques (taille < 5 mm) est aujourd'hui trĂšs mĂ©diatisĂ©e et trouve une caisse de rĂ©sonance importante dans notre sociĂ©tĂ© civile. Concomitamment, la communautĂ© scientifique dĂ©montre les impacts nĂ©gatifs gĂ©nĂ©rĂ©s par cette pollution plastique sur les Ă©cosystĂšmes. Il en rĂ©sulte aujourd'hui que les actions gouvernementales et autres actions locales et rĂ©gionales se multiplient. La rĂ©gion des Pays de la Loire, dans le cadre de la stratĂ©gie « ambition marine » de 2018, vise spĂ©cifiquement la pollution plastique, et prĂ©cise que des initiatives trĂšs concrĂštes de rĂ©duction sont dĂ©jĂ  opĂ©rationnelles ou sur le point de l'ĂȘtre. Nantes MĂ©tropole, territoire reconnu « ZĂ©ro dĂ©chet, zĂ©ro gaspillage » soutient Ă©galement des initiatives expĂ©rimentales, innovantes, contribuant Ă  un territoire zĂ©ro dĂ©chet. Évaluer la mise en oeuvre de ces actions quelle que soit leur forme - de la sensibilisation Ă  la gestion intĂ©grĂ©e et concertĂ©e au niveau d'un territoire - constitue un enjeu. Le projet Plasti-nium vise Ă  offrir un accompagnement scientifique de ces programmes, et de bien articuler l'acquisition des connaissances, leur transfert et les actions des politiques publiques. Cet accompagnement peut largement contribuer au rayonnement national et international de ces initiatives. Dans cette dĂ©marche, la finalitĂ© du projet Plasti-nium est de fournir un cadre de rĂ©flexion et d'expertise pour alimenter l'Ă©laboration et la mise en oeuvre du plan rĂ©gional de prĂ©vention et de gestion des dĂ©chets avec lequel la RĂ©gion ambitionne d'ĂȘtre un territoire leader en termes de gestion des dĂ©chets

    Projet Plasti-nium (2021-2025) : DĂ©bris plastiques dans le continuum Terre-Mer

    No full text
    15e JournĂ©e scientifique de l'OSUNA, NANTES, FRANCE, 03-/06/2022 - 03/06/2022Le projet Plasti-nium - DĂ©bris Plastiques dans le continuum terre-mer - ambitionne d'Ă©tudier la pollution plastique de la ville jusqu'Ă  la mer et de crĂ©er une dynamique transverse et interdisciplinaire sur cette thĂ©matique au sein de la RĂ©gion des Pays de la Loire. La problĂ©matique des dĂ©bris plastiques et plus spĂ©cifiquement des microplastiques (taille < 5 mm) est aujourd'hui trĂšs mĂ©diatisĂ©e et trouve une caisse de rĂ©sonance importante dans notre sociĂ©tĂ© civile. Concomitamment, la communautĂ© scientifique dĂ©montre les impacts nĂ©gatifs gĂ©nĂ©rĂ©s par cette pollution plastique sur les Ă©cosystĂšmes. Il en rĂ©sulte aujourd'hui que les actions gouvernementales et autres actions locales et rĂ©gionales se multiplient. La rĂ©gion des Pays de la Loire, dans le cadre de la stratĂ©gie « ambition marine » de 2018, vise spĂ©cifiquement la pollution plastique, et prĂ©cise que des initiatives trĂšs concrĂštes de rĂ©duction sont dĂ©jĂ  opĂ©rationnelles ou sur le point de l'ĂȘtre. Nantes MĂ©tropole, territoire reconnu « ZĂ©ro dĂ©chet, zĂ©ro gaspillage » soutient Ă©galement des initiatives expĂ©rimentales, innovantes, contribuant Ă  un territoire zĂ©ro dĂ©chet. Évaluer la mise en oeuvre de ces actions quelle que soit leur forme - de la sensibilisation Ă  la gestion intĂ©grĂ©e et concertĂ©e au niveau d'un territoire - constitue un enjeu. Le projet Plasti-nium vise Ă  offrir un accompagnement scientifique de ces programmes, et de bien articuler l'acquisition des connaissances, leur transfert et les actions des politiques publiques. Cet accompagnement peut largement contribuer au rayonnement national et international de ces initiatives. Dans cette dĂ©marche, la finalitĂ© du projet Plasti-nium est de fournir un cadre de rĂ©flexion et d'expertise pour alimenter l'Ă©laboration et la mise en oeuvre du plan rĂ©gional de prĂ©vention et de gestion des dĂ©chets avec lequel la RĂ©gion ambitionne d'ĂȘtre un territoire leader en termes de gestion des dĂ©chets

    Projet Plasti-nium (2021-2025) : DĂ©bris plastiques dans le continuum Terre-Mer

    No full text
    15e JournĂ©e scientifique de l'OSUNA, NANTES, FRANCE, 03-/06/2022 - 03/06/2022Le projet Plasti-nium - DĂ©bris Plastiques dans le continuum terre-mer - ambitionne d'Ă©tudier la pollution plastique de la ville jusqu'Ă  la mer et de crĂ©er une dynamique transverse et interdisciplinaire sur cette thĂ©matique au sein de la RĂ©gion des Pays de la Loire. La problĂ©matique des dĂ©bris plastiques et plus spĂ©cifiquement des microplastiques (taille < 5 mm) est aujourd'hui trĂšs mĂ©diatisĂ©e et trouve une caisse de rĂ©sonance importante dans notre sociĂ©tĂ© civile. Concomitamment, la communautĂ© scientifique dĂ©montre les impacts nĂ©gatifs gĂ©nĂ©rĂ©s par cette pollution plastique sur les Ă©cosystĂšmes. Il en rĂ©sulte aujourd'hui que les actions gouvernementales et autres actions locales et rĂ©gionales se multiplient. La rĂ©gion des Pays de la Loire, dans le cadre de la stratĂ©gie « ambition marine » de 2018, vise spĂ©cifiquement la pollution plastique, et prĂ©cise que des initiatives trĂšs concrĂštes de rĂ©duction sont dĂ©jĂ  opĂ©rationnelles ou sur le point de l'ĂȘtre. Nantes MĂ©tropole, territoire reconnu « ZĂ©ro dĂ©chet, zĂ©ro gaspillage » soutient Ă©galement des initiatives expĂ©rimentales, innovantes, contribuant Ă  un territoire zĂ©ro dĂ©chet. Évaluer la mise en oeuvre de ces actions quelle que soit leur forme - de la sensibilisation Ă  la gestion intĂ©grĂ©e et concertĂ©e au niveau d'un territoire - constitue un enjeu. Le projet Plasti-nium vise Ă  offrir un accompagnement scientifique de ces programmes, et de bien articuler l'acquisition des connaissances, leur transfert et les actions des politiques publiques. Cet accompagnement peut largement contribuer au rayonnement national et international de ces initiatives. Dans cette dĂ©marche, la finalitĂ© du projet Plasti-nium est de fournir un cadre de rĂ©flexion et d'expertise pour alimenter l'Ă©laboration et la mise en oeuvre du plan rĂ©gional de prĂ©vention et de gestion des dĂ©chets avec lequel la RĂ©gion ambitionne d'ĂȘtre un territoire leader en termes de gestion des dĂ©chets
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