Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
Six morphotypes of small mussels (Bivalvia: Mytilidae) were found attached to naturally sunken wood collected in the Bohol Sea (Philippines). These specimens are related to the large Bathymodiolus mussels that are found worldwide at cold seeps and hydrothermal vents. In these habitats, the mytilids harbour sulphur- and methane-oxidizing endosymbionts in their gills and depend on the energy and carbon provided by the symbionts. In this study, bacteria associated with the gills of wood-associated mussels are characterized using molecular and microscopic techniques. The existence of bacteria in the lateral zone of gill filaments in all specimens is demonstrated. Comparative analyses of 16S rRNA gene and adenosine 5′-phosphosulphate (APS) reductase gene sequences indicate that the bacteria are closely related to sulphur-oxidizing endosymbionts of Bathymodiolus. FISHs using specific probes confirm that sulphur oxidizers are by far the most abundant, if not the only bacteria present. Electron micrographs displayed mostly extracellular bacteria located between microvilli at the apical surface of host gill epithelial cells all along the lateral zone of each gill filament. In some specimens, occasional occurrence of intracellular bacteria with similar morphology was noted. This study provides the first molecular evidence for the presence of possible thiotrophic symbiosis in sunken wood ecosystems. With their epibiotic bacteria, wood-associated mussels display a less integrated type of interaction than described in their seep, vent and whale fall relatives.
ISSN: 0168-6496

hal-00715244
https://hal.univ-antilles.fr/hal-00715244
DOI : 10.1111/j.1574-6941.2008.00438.x

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
: Human exposure to xenobiotics is usually estimated by indirect methods. Biological monitoring has emerged during the last decade to improve assessment of exposure. However, biomonitoring is still an analytical challenge, because the amounts of sample available are often very small yet analysis must be as thorough and sensitive as possible. The purpose of this work was to develop an untargeted "exposomics" approach by using ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS), which was applied to the characterization of pesticide metabolites in urine from pregnant women from a French epidemiological cohort. An upgradable list of pesticides commonly used on different crops, with their metabolites (more than 400 substances) was produced. Raw MS data were then processed to extract signals from these substances. Metabolites were identified by tandem mass spectrometry; putative identifications were validated by comparison with standards and metabolites generated by experiments on animals. Finally, signals of identified compounds were statistically analyzed by use of multivariate methods. This enabled discrimination of exposure groups, defined by indirect methods, on the basis of four metabolites from two fungicides (azoxystrobin, fenpropimorph) used in cereal production. This original approach applied to pesticide exposure can be extended to a variety of contaminant families for upstream evaluation of exposure from food and the environment.
ISSN: 1618-2642

hal-00875889
https://hal.archives-ouvertes.fr/hal-00875889
DOI : 10.1007/s00216-013-7136-2
PUBMED : 23892877

Éditeur(s) : HAL CCSD
Résumé : 16 p.
National audience
The objective of this paper is to present an approach for experimenting territorial prospective analysis based on spatial modelling. This approach is carried out in the framework of the DESCARTES project which aims at developing a spatial simulation tool to support the design and analysis of different scenarios for land-use allocation in Reunion Island in terms of environmental services. The spatial modelling tool is composed of two complementary applications: (i) the Ocelet modelling language and its land dynamics simulation environment, and (ii) the Margouill@ platform. The first demonstrator, a model of farm land consumption by urbanization, was developed and presented during workshops in order to test the role of the spatial simulation tool in support of a collaborative innovation process among stakeholders, and to foster new research on social learning, spatial simulation of environmental services, and scale change issues.
L'objectif de cet article est de présenter une démarche de construction d'un exercice de prospective territoriale basé sur un outil de modélisation spatiale. Cette démarche est mise en œuvre dans le cadre du projet ANR DESCARTES dont l'objectif est de construire un outil de simulation cartographique pour analyser différents scénarios d'affectation de l'usage des sols à l'Ile de La Réunion, en termes de services environnementaux. La plateforme de simulation cartographique est composée de deux applications complémentaires (i) le langage de modélisation Ocelet et son environnement de simulation de paysages dynamiques, et (ii) la plateforme Margouill@. Le développement puis la présentation, en atelier, d'un premier démonstrateur sur la consommation des terres agricoles par l'urbanisation a permis de tester l'outil cartographique comme support d'un processus d'innovation collective entre les parties prenantes, et d'ouvrir de nouveaux champs de recherche sur l'analyse de la démarche par les apprentissages, la spatialisation et la simulation prospective des services écosystémiques, et la prise en compte du changement d'échelle.
Acte de la Conférence Internationale de Géomatique et d'Analyse Spatiale
Brest, France

cirad-00850243
http://hal.cirad.fr/cirad-00850243
http://hal.cirad.fr/cirad-00850243/document
http://hal.cirad.fr/cirad-00850243/file/SAGEO-Brest2013-version_finale.pdf

Éditeur(s) : HAL CCSD
Résumé : International audience
Background: Mounier-Kuhn syndrome (MKS) is a rare disorder characterized by enlargement of the trachea and main bronchi and associated with recurrent respiratory tract infections. Objective: This multicenter, retrospective study was carried out to describe respiratory conditions associated with tracheobronchomegaly. Methods: Nine institutions involved in the ‘Groupe d'Endoscopie de Langue Française' (GELF) participated in this study. A standard form was used to record patient characteristics, treatments and follow-up from medical charts. Results: Seventeen patients, 53% male, aged 58 ± 18 years at diagnosis were included. Recurrent infections revealed MKS in 88% of cases. Main comorbid conditions were diffuse bronchiectasis in 88% of patients and tracheobronchomalacia in 67% of cases. The exacerbation rate was 1.5 exacerbations/patient/year. The main non-respiratory morbid condition was gastroesophageal reflux disease in 29% of cases. Interventional bronchoscopy was performed in seven patients (41%), consisting of laser (n = 2) and tracheal stenting (n = 5). Complications related to stents were observed in 80% of cases with a mean stent duration of 8 months. Four deaths, including three due to respiratory causes, occurred during follow-up. Conclusions: This is the largest series of MKS reported in the literature, showing that bronchiectasis and tracheobronchomalacia are the main associated morbid conditions that constitute a challenge for treatment.
Respiration

hal-01331182
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01331182
DOI : 10.1159/000445029
PUBMED : 27022925

Éditeur(s) : HAL CCSD Taylor & Francis
Résumé : International audience
The astronomical and geodetic observatory OCA, located on the karst plateau of Calern (Caussols, France), has been monitoring earth deformation for several years. Two long baseline tiltmeters have been installed in a shaft in 2007, along with classical hydrogeological monitoring tools in order to investigate the relationship between current karst deformation and hydrology. Dye tests have shown that the plateau is drained towards the East, to the spring of Bramafam, except for its Western third. Karst tilting, as recorded by the tiltmeters, is linked to rainfall events. These instruments bring additional information to characterize different reservoirs: the deep karst aquifer of Bramafan with high amplitude oscillations of its water table, up to 100 m, the perched aquifer of Moustiques shaft whose response is attenuated, and several slope aquifers with reduced oscillations (Fontaniers, Castel Bon Pré). Tilt deformation reaches 8 μrad with a definite orientation between N90°E and N100°E. The best correlation between hydrology and tilts is observed for the deep aquifers. If the first autumn rainfall is ineffective on tilt, it recharges the epikarst and refills the reserves. The winter rains cause the water to flush towards the eastern deep aquifer and provokes a quick tilting of the plateau. Finally, the long term variations in tilt and water table show a very good correlation The relationship between current hydrological deformations and tectonics is also analyzed; broken and shifted speleothems in the shafts indicate a general shift of the plateau towards the south.
ISSN: 0985-3111

hal-00708116
https://hal.archives-ouvertes.fr/hal-00708116
https://hal.archives-ouvertes.fr/hal-00708116/document
https://hal.archives-ouvertes.fr/hal-00708116/file/2010_Geodinamica_Calern_final.pdf
BIBCODE : 10.3166/ga.23.49-64

Éditeur(s) : HAL CCSD
Résumé : International audience
AIM:We aimed to study the relationships between circulating 25-hydroxyvitamin D [25(OH)D], insulin resistance and leptin-to-adiponectin (L/A) ratio in Guadeloupean children and adolescents and to analyse the changes in 25(OH)D levels after a 1-year lifestyle intervention program.METHODS:25(OH)D concentrations were measured via a chemiluminescence assay. Cardiometabolic risk factors, homoeostasis model assessment of insulin resistance (HOMA-IR), and adipokines were measured. The lifestyle intervention included dietary counselling, regular physical activity.RESULTS:Among 117 girls and boys (11–15 years old, 31.6% obese), 40% had vitamin D deficiency (25(OH)D levels < 20 ng/mL). With linear regression models where 25(OH)D and HOMA-IR acted as independent variables and age, sex, BMI, L/A ratio as covariates, 25(OH)D was significantly associated with HOMA-IR alone (P = 0.036). HOMA-IR was also associated with BMI z-score ≥ 2, L/A ratio and an interaction term BMI z-score ≥ 2*L/A ratio (P < 0.001 for all). After one year, in 78 children/adolescent, mean serum 25(OH)D increased significantly from 21.4 ± 4.9 ng/mL at baseline to 23.2 ± 6.0 after 1 year; P = 0.003 whereas BMI z-score, HOMA-IR and L/A ratio decreased significantly (P = 0.003, P < 0.001 and P = 0.012; respectively).CONCLUSION:The association between 25(OH)D and HOMA-IR, independently of obesity and the high prevalence of vitamin D deficiency should be considered in order to prevent the later incidence of T2DM. A healthy lifestyle including non-sedentary and outdoor activities could be a way for improving vitamin D status.
Open Access Macedonian Journal of Medical Sciences

hal-01427889
http://hal.upmc.fr/hal-01427889
PUBMEDCENTRAL : PMC5175505