Global phylogeography of marine synechococcus in coastal areas reveals strong community shifts

Marine Synechococcus comprise a numerically and ecologically prominent phytoplankton group, playing a major role in both carbon cycling and trophic networks in all oceanic regions except in the polar oceans. Despite their high abundance in coastal areas, our knowledge of Synechococcus communities in these environments is based on only a few local studies. Here, we use the global metagenome data set of the Ocean Sampling Day (June 21st, 2014) to get a snapshot of the taxonomic composition of coastal Synechococcus communities worldwide, by recruitment on a reference database of 141 picocyanobacterial genomes, representative of the whole Prochlorococcus, Synechococcus, and Cyanobium diversity. This allowed us to unravel drastic community shifts over small to medium scale gradients of environmental factors, in particular along European coasts. The combined analysis of the phylogeography of natural populations and the thermophysiological characterization of eight strains, representative of the four major Synechococcus lineages (clades I to IV), also brought novel insights about the differential niche partitioning of clades I and IV, which most often co-dominate the Synechococcus community in cold and temperate coastal areas. Altogether, this study reveals several important characteristics and specificities of the coastal communities of Synechococcus worldwide

Coordination et mobilisation des acteurs locaux dans les Contrats locaux de santé des régions Bretagne et Pays de la Loire

Within the framework of the inter-regional health research, evaluation and expertise scheme (DIREES), EHESP was awarded a mandate to study Local Health Contracts (CLS) by the ARS Bretagne and Pays-de-la-Loire. The first part of the mandate aimed to improve the understanding of the impact and added value of the CLSs deployed in their territories in terms of health promotion and environmental health.The second part, which is the subject of this report, aimed to understand the issues relating to the management and mobilisation of actors within a CLS in order to improve their actions to tackle social inequalities in health.Dans le cadre du dispositif inter-régional de recherche, d’évaluation et d’expertise en santé (DIREES), un mandat portant sur les Contrats Locaux de Santé (CLS) a été octroyé à l’EHESP par les ARS Bretagne et Pays-de-la-Loire. Son premier volet visait à améliorer la compréhension des impacts et de la plus-value des CLS déployés sur leur territoire en matière de promotion de la santé et de santé environnement.Le second volet, faisant l’objet du présent rapport, visait quant à lui à saisir les enjeux relatifs au pilotage et à la mobilisation des acteurs au sein d'un CLS afin de tendre vers une amélioration de leurs actions visant à lutter contre les inégalités sociales de santé

Stochastic and Deterministic Processes Regulate Phytoplankton Assemblages in a Temperate Coastal Ecosystem

International audienceAssessing the relative contributions of the interacting deterministic andstochastic ecological processes for phytoplankton community assembly is crucial inunderstanding and predicting community organization and succession at differenttemporal and spatial scales. In this study, we hypothesized that deterministic and sto-chastic ecological processes regulating phytoplankton, present seasonal and repeatingpatterns. This hypothesis was explored during a 5-year survey (287 samples) conductedat a small spatial scale (;15km) in a temperate coastal ecosystem (eastern EnglishChannel). Microscopy and flow cytometry quantified phytoplankton abundance andbiomass, while metabarcoding data allowed an extended evaluation of diversity andthe exploration of the ecological processes regulating phytoplankton using null modelanalysis. Alpha diversity of phytoplankton was governed by the effect of environmen-tal conditions (environmental filtering). Temporal community turnover (beta diversity)evidenced a consistent interannual pattern that determined the phytoplankton sea-sonal structure. In winter and early spring (from January to March), determinism (ho-mogeneous selection) was the major process in the phytoplankton community assem-bly. The overall mean in the year was 38%. Stochastic processes (ecological drift)prevailed during the rest of the year from April to December, where the overall meanfor the year was 55%. The maximum values were recorded in late spring and summer,which often presented recurrent and transient monospecific phytoplankton peaks.Overall, the prevalence of stochastic processes rendered less predictable seasonal dy-namics of phytoplankton communities to future environmental change.IMPORTANCE While ecological deterministic processes are conducive to modeling,stochastic ones are far less predictable. Understanding the overall assembly processesof phytoplankton is critical in tracking and predicting future changes. The novelty ofthis study was that it addressed a long-posed question, on a pluriannual scale. Wasseasonal phytoplankton succession influenced by deterministic processes (e.g., abioticenvironment) or by stochastic ones (e.g., dispersal, or ecological drift)? Our results pro-vided strong support for a seasonal and repeating pattern with stochastic processes(drift) prevailing during most of the year and periods with monospecific phytoplank-ton peaks

An innovative automated active compound screening system allows high-throughput optimization of somatic embryogenesis in Coffea arabica

International audienceSomatic embryogenesis (SE) faces many challenges in fulfilling the growing demand for elite materials. A high-throughput approach is required to accelerate the optimization of SE protocols by multiplying experimental conditions within a limited time period. For the first time in plant micropropagation, we have developed a miniaturized and automated screening system to meet high-throughput standards. Coffea arabica embryo regeneration, classically achieved in 250-ml Erlenmeyer flasks, was successfully miniaturized in 24-well plates, allowing a volume downscaling factor of 100 and a space saving of 53 cm 2 /well. Cell clusters were ground and filtered to fit the automated pipetting platform, leading to fast, reproducible and uniform cluster distribution (23.0 ± 5.5 cell clusters/well) and successful regeneration (6.5 ± 2.2 embryos/well). Pilot screening of active compounds on SE was carried out. Compounds belonging to the histone deacetylase inhibitor family were tested for embryo regeneration efficiency. Cells treated with 1 µM Trichostatin A showed a marked 3-fold increase in the number of regenerated embryos. When re-tested in 250-ml flasks, the same enhancement was obtained, thereby validating the miniaturized and automated screening method. These results showed that our screening system is reliable and well suited to screening hundreds of compounds, offering unprecedented perspectives in plant micropropagation

Towards outpatient management of tubo-ovarian abscesses?

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Thermoacclimation and genome adaptation of the membrane lipidome in marine Synechococcus

International audienceThe marine cyanobacteria of the genus Synechococcus are important primary producers, displaying a wide latitudinal distribution that is underpinned by diversification into temperature ecotypes. The physiological basis underlying these ecotypes is poorly known. In many organisms, regulation of membrane fluidity is crucial for acclimating to variations in temperature. Here, we reveal the detailed composition of the membrane lipidome of the model strain Synechococcus sp. WH7803 and its response to temperature variation. Unlike freshwater strains, membranes are almost devoid of C18, mainly containing C14 and C16 chains with no more than two unsaturations. In response to cold, we observed a rarely observed process of acyl chain shortening that likely induces membrane thinning, along with specific desaturation activities. Both of these mechanisms likely regulate membrane fluidity, facilitating the maintenance of efficient photosynthetic activity. A comprehensive examination of 53 Synechococcus genomes revealed clade-specific gene sets regulating membrane lipids. In particular, the genes encoding desaturase enzymes, which is a key to the temperature stress response, appeared to be temperature ecotype-specific, with some of them originating from lateral transfers. Our study suggests that regulation of membrane fluidity has been among the important adaptation processes for the colonization of different thermal niches by marine Synechococcus

Patients' perspectives on how to improve endometriosis care: A large qualitative study within the ComPaRe-Endometriosis e-cohort

International audienceEndometriosis is a chronic gynecological condition that affects about 10% of women of reproductive age. Despite its prevalence, diagnosis is often delayed, misdiagnosis is common, and treatment options are poor. This study aimed at capturing ideas to improve endometriosis care from the patients' perspectives. Materials and Methods: We analyzed cross-sectional data from 1,000 adult patients in ComPaRe-Endometriosis (a French prospective e-cohort focused on endometriosis) who answered to the open-ended question: "If you had a magic wand, what would you change about your health care?". The free-text responses were analyzed by qualitative thematic analysis using an inductive approach. Results: Patients had a mean age of 34.1 years (standard deviation = 8.1); 56% and 42% had stage IV disease or deep endometriosis, respectively. They elicited 2,487 ideas to improve the management of endometriosis, which were categorized into 61 areas of improvement, further grouped into 14 themes. The top five areas of improvement were mentioned by >10% of the patients and were to (1) train caregivers to develop their knowledge on the disease, (2) provide better management of daily pain and pain attacks, (3) take patient-reported symptoms seriously, (4) standardize diagnostic processes to improve early detection, and (5) have caregivers listen more to the patients. Conclusions: We identified 61 areas for improvement in endometriosis care. These results reflect patients' expectations in terms of management of their disease and will be useful to design a better global care for endometriosis from the patients' perspectives

Unveiling membrane thermoregulation strategies in marine picocyanobacteria

International audienceThe wide latitudinal distribution of marine Synechococcus cyanobacteria partly relies on the differentiation of lineages adapted to distinct thermal environments. Membranes are highly thermosensitive cell components, and the ability to modulate their fluidity can be critical for the fitness of an ecotype in a particular thermal niche. We compared the thermophysiology of Synechococcus strains representative of major temperature ecotypes in the field. We measured growth, photosynthetic capacities and membrane lipidome variations. We carried out a metagenomic analysis of stations of the Tara Oceans expedition to describe the latitudinal distribution of the lipid desaturase genes in the oceans. All strains maintained efficient photosynthetic capacities over their different temperature growth ranges. Subpolar and cold temperate strains showed enhanced capacities for lipid monodesaturation at low temperature thanks to an additional, poorly regiospecific Delta 9-desaturase. By contrast, tropical and warm temperate strains displayed moderate monodesaturation capacities but high proportions of double unsaturations in response to cold, thanks to regiospecific Delta 12-desaturases. The desaturase genes displayed specific distributions directly related to latitudinal variations in ocean surface temperature. This study highlights the critical importance of membrane fluidity modulation by desaturases in the adaptive strategies of Synechococcus cyanobacteria during the colonization of novel thermal niches

Global phylogeography of marine Synechococcus in coastal areas reveals strikingly different communities than in the open ocean

Abstract Marine Synechococcus comprise a numerically and ecologically prominent phytoplankton group, playing a major role in both carbon cycling and trophic networks in all oceanic regions except in the polar oceans. Despite their high abundance in coastal areas, our knowledge of Synechococcus communities in these environments is based on only a few local studies. Here, we use the global metagenome dataset of the Ocean Sampling Day (June 21 st 2014) to get a snapshot of the taxonomic composition of coastal Synechococcus communities worldwide, by recruitment on a reference database of 141 picocyanobacterial genomes, representative of the whole Prochlorococcus, Synechococcus and Cyanobium diversity. This allowed us to unravel drastic community shifts over small to medium scale gradients of environmental factors, in particular along European coasts. The combined analysis of the phylogeography of natural populations and the thermophysiological characterization of eight strains, representative of the four major Synechococcus lineages (clades I to IV), also brought novel insights about the differential niche partitioning of clades I and IV, which most often co-dominate the Synechococcus community in cold and temperate coastal areas. Altogether, this study tackles the main differences between open-ocean and coastal communities worldwide

Role of SPECT/CT Compared With MRI in the Diagnosis and Management of Patients With Wrist Trauma Occult Fractures.

International audienceBACKGROUND: The diagnosis of wrist fractures, especially scaphoid fractures, remains a challenge because of nonunion risk. Currently, new hybrid technologies are emerging such as SPECT/CT systems, which combine functional and anatomical data sets. So, we wanted to evaluate the utility of SPECT/CT in the management of occult carpal fractures. METHODS: In this study, all patients addressed at the orthopedic department at Brest University Hospital for wrist pain after trauma with initial normal plain radiographs were prospectively included. Patients with normal radiographs but with signs strongly suggestive of clinical fracture underwent a bone SPECT/CT and an MRI of the wrist. Therapeutic management took into account the results of all modalities, and all patients were followed up for at least 6 months and reviewed by the same surgeon. SPECT/CT findings were compared with those of the other modalities and follow-up. RESULTS: From December 2009 to May 2011, 57 patients were enrolled. Fifty-seven SPECT/CT and 52 MRI scans were obtained. Twenty-eight patients had normal imaging results, whereas 29 patients presented bone bruise and/or fractures. Ten patients were concordant according to SPECT/CT and MRI; 2 patients presented fractures on SPECT/CT without MRI performed; 17 patients had partially discordant results. Only 1 patient presented a nonunion at the follow-up, whereas both investigations were positive. CONCLUSIONS: This study highlights the good performances of SPECT/CT, which allows the detection of most occult carpal fractures. When a carpal occult fracture is strongly suspected clinically, SPECT/CT might be proposed at first intention after normal radiographs