18 research outputs found
Protein kinase CK2 contributes to the organization of sodium channels in axonal membranes by regulating their interactions with ankyrin G
In neurons, generation and propagation of action potentials requires the precise accumulation of sodium channels at the axonal initial segment (AIS) and in the nodes of Ranvier through ankyrin G scaffolding. We found that the ankyrin-binding motif of Nav1.2 that determines channel concentration at the AIS depends on a glutamate residue (E1111), but also on several serine residues (S1112, S1124, and S1126). We showed that phosphorylation of these residues by protein kinase CK2 (CK2) regulates Nav channel interaction with ankyrins. Furthermore, we observed that CK2 is highly enriched at the AIS and the nodes of Ranvier in vivo. An ion channel chimera containing the Nav1.2 ankyrin-binding motif perturbed endogenous sodium channel accumulation at the AIS, whereas phosphorylation-deficient chimeras did not. Finally, inhibition of CK2 activity reduced sodium channel accumulation at the AIS of neurons. In conclusion, CK2 contributes to sodium channel organization by regulating their interaction with ankyrin G
Impact of Vitamin D Supplementation on Influenza Vaccine Response and Immune Functions in Deficient Elderly Persons: A Randomized Placebo-Controlled Trial
Background: Immunosenescence contributes to reduced vaccine response in elderly persons, and is worsened by deficiencies in nutrients such as Vitamin (Vit-D). The immune system is a well-known target of Vit-D, which can both potentiate the innate immune response and inhibit the adaptive system, and so modulate vaccination response.Objective: This randomized placebo-controlled double-blind trial investigated whether Vit-D supplementation in deficient elderly persons could improve influenza seroprotection and immune response.Design: Deficient volunteers (Vit-D serum <30 ng/mL) were assigned (V1) to receive either 100,000 IU/15 days of cholecalciferol (D, n = 19), or a placebo (P, n = 19), over a 3 month period. Influenza vaccination was performed at the end of this period (V2), and the vaccine response was evaluated 28 days later (V3). At each visit, serum cathelicidin, immune response to vaccination, plasma cytokines, lymphocyte phenotyping, and phagocyte ROS production were assessed.Results: Levels of serum 25-(OH)D increased after supplementation (D group, V1 vs. V2: 20.7 ± 5.7 vs. 44.3 ± 8.6 ng/mL, p < 0.001). No difference was observed for serum cathelicidin levels, antibody titers, and ROS production in D vs. P groups at V3. Lower plasma levels of TNFα (p = 0.040) and IL-6 (p = 0.046), and higher ones for TFGÎČ (p = 0.0028) were observed at V3. The Th1/Th2 ratio was lower in the D group at V2 (D: 0.12 ± 0.05 vs. P: 0.18 ± 0.05, p = 0.039).Conclusions: Vit-D supplementation promotes a higher TGFÎČ plasma level in response to influenza vaccination without improving antibody production. This supplementation seems to direct the lymphocyte polarization toward a tolerogenic immune response. A deeper characterization of metabolic and molecular pathways of these observations will aid in the understanding of Vit-D's effects on cell-mediated immunity in aging. This clinical trial was registered at clinicaltrials.gov as NCT01893385
Feeding mice with diets containing mercury-contaminated fish flesh from French Guiana: a model for the mercurial intoxication of the Wayana Amerindians
International audienc
Méthodologie d'évaluation hybride des interactions entre la biodiversité et les systÚmes urbains : vers une synergie entre l'Analyse de Cycle de Vie, l'expertise écologie et la data science
The ongoing 6th mass extinction event put biodiversity preservation on the same level as climate change in the list of public policy priorities (e.g. French Biodiversity Plan, 2018). The construction industry has already been asked to assess the carbon footprint of their new projects (e.g. future environmental regulations for new buildings, RE 2020). It has now also become necessary to have tools capable of measuring these projectsâ impacts on biodiversity. One can list five major risks facing biodiversity: habitats loss, global warming, pollution, resources overexploitation and invasive species introduction. These risks can have local causes - on the construction site of a project â or global ones. Both common and endangered species are affected by these risks. In this context, the scientific goal of this Ph.D. is to develop a reliable and robust methodology to evaluate interactions between biodiversity and urban systems. The operational goal is to design tooling that will support with the identification of the most favorable scenarios of construction for biodiversity. We propose a hybrid methodology to evaluate the interaction between biodiversity and urban system. It is based on a combination of ecology, Life Cycle Assessment (LCA) and data science. It takes into account the interactions between urban systems and in-situ (local) or ex-situ (global) biodiversity, as well as the five risks it is facing. The multi-scale process underlying the strategy involves a vertical development of the method (component, building, plot, district, territory). The main methodological developments consider:- The urban plantsâ life cycle: three data sets were structured according to the selected criteria for the proposed hybrid method: 1) Plants used in an urban setting, 2) Specific richness of floristic species for the habitats in the region Ile-de-France, 3) Environmental data for urban plants;- The construction project location specificities: a model, a database and a programming tool allow the calculation of a land use indicator, specific for the Ile-de-France region, with nearly 900 possible combinations of soil transformation;- The compatibility of the hybrid method with the methods and tools promoted by the regulatory bodies: linear regression models and a programming tool allow the calculation of ex-situ impacts from the outputs of environmental assessment software compatible with RE2020 (i.e. ELODIE)The methodâs operability to identify the levers of action was tested on a real case study, on the scale of a building, in the Ile-de-France region (EPA Marne project). Developments for the hybrid methodâs application to larger scales are proposed using specific tools suitable to each scale, such as BIM / CIM (Building / City Information Modeling) and a district scale evaluation software based on the RE2020 approach (ie UrbanPrint).Face au 6Ăšme phĂ©nomĂšne dâextinction de masse, la prĂ©servation de la biodiversitĂ© a Ă©tĂ© placĂ©e au mĂȘme rang que le changement climatique dans les prioritĂ©s des politiques publiques (par ex. Plan BiodiversitĂ© adoptĂ© en 2018). Ă lâinstar de la nĂ©cessitĂ© dâĂ©valuer lâempreinte carbone des projets de construction (par ex. future RĂ©glementation Environnementale pour les bĂątiments neufs RE 2020), il apparait aujourdâhui nĂ©cessaire de se munir dâoutils capables de mesurer lâempreinte biodiversitĂ© du cadre bĂąti. Cinq grandes pressions sâexercent sur la biodiversitĂ© : la perte dâhabitats, le rĂ©chauffement climatique, les pollutions, la surexploitation des ressources et lâintroduction dâespĂšces invasives. Ces pressions sâexercent sur la biodiversitĂ©, au niveau local (sur le site dâun projet de construction) et global (planĂ©taire). Quâelle soit considĂ©rĂ©e comme ordinaire ou reconnue comme menacĂ©e, la biodiversitĂ© dans son ensemble est affectĂ©e par ces pressions. Dans ce contexte, lâobjectif scientifique de la thĂšse est de dĂ©velopper une mĂ©thodologie fiable et robuste dâĂ©valuation des interactions entre les systĂšmes urbains et la biodiversitĂ©. Lâobjectif opĂ©rationnel est dâaboutir Ă des outils dâaide Ă la dĂ©cision, qui permettent dâidentifier les scĂ©narios de construction les plus favorables Ă la biodiversitĂ©. Une mĂ©thodologie dâĂ©valuation Hybride des Interactions BiOdiversitĂ© / systĂšme Urbain est proposĂ©e (mĂ©thodologie dâĂ©valuation HIBOU). Elle est basĂ©e sur la synergie entre lâĂ©cologie, lâAnalyse de Cycle de Vie (ACV) et la data science. Elle permet de prendre en compte les interactions entre les systĂšmes urbains et la biodiversitĂ© in-situ (locale) et ex-situ (globale), ainsi que les cinq pressions qui sâexercent sur la biodiversitĂ©. Le jeu dâĂ©chelle sous-jacent Ă la stratĂ©gie implique un dĂ©veloppement de type gigogne des travaux (composant, bĂątiment, parcelle, quartier, territoire). Les principaux dĂ©veloppements mĂ©thodologiques concernent :- La prise en compte du cycle de vie des vĂ©gĂ©taux urbains dans lâĂ©valuation : trois bases de donnĂ©es ont Ă©tĂ© structurĂ©es selon les critĂšres nĂ©cessaires Ă la mĂ©thode hybride proposĂ©e : 1) VĂ©gĂ©taux utilisĂ©s en ville, 2) Richesse SpĂ©cifique Floristique des Habitats en Ile de France, 3) DonnĂ©es environnementales pour les vĂ©gĂ©taux urbains ;- La prise en compte des spĂ©cificitĂ©s du site dâimplantation du projet : un modĂšle, une base de donnĂ©es et un outil de programmation permettent le calcul dâun indicateur dâutilisation des sols spĂ©cifique Ă lâIle de France avec prĂšs de 900 combinaisons possibles de transformation des sols ;- La compatibilitĂ© de la mĂ©thode hybride avec les mĂ©thodes et outils promus par la rĂ©glementation : des modĂšles de rĂ©gression linĂ©aire et un outil de programmation permettent le calcul des impacts sur la biodiversitĂ© ex-situ Ă partir des sorties dâun logiciel dâĂ©valuation environnementale conforme Ă la RE2020 (i.e. ĂLODIE)LâopĂ©rationnalitĂ© de la mĂ©thode pour lâidentification des leviers dâaction a Ă©tĂ© testĂ©e par application sur un cas dâĂ©tude rĂ©el, Ă lâĂ©chelle bĂątiment, en Ile de France (projet EPA Marne). Des dĂ©veloppements pour application de la mĂ©thode hybride aux Ă©chelles supĂ©rieures sont proposĂ©s Ă partir des outils traitant ces Ă©chelles comme le BIM/CIM (Building/City Information Modeling) et un logiciel dâĂ©valuation Ă lâĂ©chelle du quartier basĂ© sur la mĂȘme approche que la RE2020 (i.e. UrbanPrint)
Methodology to assess the interaction between biodiversity and urban system : toward a synergy of LCA, ecological expertise and data science
Face au 6Ăšme phĂ©nomĂšne dâextinction de masse, la prĂ©servation de la biodiversitĂ© a Ă©tĂ© placĂ©e au mĂȘme rang que le changement climatique dans les prioritĂ©s des politiques publiques (par ex. Plan BiodiversitĂ© adoptĂ© en 2018). Ă lâinstar de la nĂ©cessitĂ© dâĂ©valuer lâempreinte carbone des projets de construction (par ex. future RĂ©glementation Environnementale pour les bĂątiments neufs RE 2020), il apparait aujourdâhui nĂ©cessaire de se munir dâoutils capables de mesurer lâempreinte biodiversitĂ© du cadre bĂąti. Cinq grandes pressions sâexercent sur la biodiversitĂ© : la perte dâhabitats, le rĂ©chauffement climatique, les pollutions, la surexploitation des ressources et lâintroduction dâespĂšces invasives. Ces pressions sâexercent sur la biodiversitĂ©, au niveau local (sur le site dâun projet de construction) et global (planĂ©taire). Quâelle soit considĂ©rĂ©e comme ordinaire ou reconnue comme menacĂ©e, la biodiversitĂ© dans son ensemble est affectĂ©e par ces pressions. Dans ce contexte, lâobjectif scientifique de la thĂšse est de dĂ©velopper une mĂ©thodologie fiable et robuste dâĂ©valuation des interactions entre les systĂšmes urbains et la biodiversitĂ©. Lâobjectif opĂ©rationnel est dâaboutir Ă des outils dâaide Ă la dĂ©cision, qui permettent dâidentifier les scĂ©narios de construction les plus favorables Ă la biodiversitĂ©. Une mĂ©thodologie dâĂ©valuation Hybride des Interactions BiOdiversitĂ© / systĂšme Urbain est proposĂ©e (mĂ©thodologie dâĂ©valuation HIBOU). Elle est basĂ©e sur la synergie entre lâĂ©cologie, lâAnalyse de Cycle de Vie (ACV) et la data science. Elle permet de prendre en compte les interactions entre les systĂšmes urbains et la biodiversitĂ© in-situ (locale) et ex-situ (globale), ainsi que les cinq pressions qui sâexercent sur la biodiversitĂ©. Le jeu dâĂ©chelle sous-jacent Ă la stratĂ©gie implique un dĂ©veloppement de type gigogne des travaux (composant, bĂątiment, parcelle, quartier, territoire). Les principaux dĂ©veloppements mĂ©thodologiques concernent :- La prise en compte du cycle de vie des vĂ©gĂ©taux urbains dans lâĂ©valuation : trois bases de donnĂ©es ont Ă©tĂ© structurĂ©es selon les critĂšres nĂ©cessaires Ă la mĂ©thode hybride proposĂ©e : 1) VĂ©gĂ©taux utilisĂ©s en ville, 2) Richesse SpĂ©cifique Floristique des Habitats en Ile de France, 3) DonnĂ©es environnementales pour les vĂ©gĂ©taux urbains ;- La prise en compte des spĂ©cificitĂ©s du site dâimplantation du projet : un modĂšle, une base de donnĂ©es et un outil de programmation permettent le calcul dâun indicateur dâutilisation des sols spĂ©cifique Ă lâIle de France avec prĂšs de 900 combinaisons possibles de transformation des sols ;- La compatibilitĂ© de la mĂ©thode hybride avec les mĂ©thodes et outils promus par la rĂ©glementation : des modĂšles de rĂ©gression linĂ©aire et un outil de programmation permettent le calcul des impacts sur la biodiversitĂ© ex-situ Ă partir des sorties dâun logiciel dâĂ©valuation environnementale conforme Ă la RE2020 (i.e. ĂLODIE)LâopĂ©rationnalitĂ© de la mĂ©thode pour lâidentification des leviers dâaction a Ă©tĂ© testĂ©e par application sur un cas dâĂ©tude rĂ©el, Ă lâĂ©chelle bĂątiment, en Ile de France (projet EPA Marne). Des dĂ©veloppements pour application de la mĂ©thode hybride aux Ă©chelles supĂ©rieures sont proposĂ©s Ă partir des outils traitant ces Ă©chelles comme le BIM/CIM (Building/City Information Modeling) et un logiciel dâĂ©valuation Ă lâĂ©chelle du quartier basĂ© sur la mĂȘme approche que la RE2020 (i.e. UrbanPrint).The ongoing 6th mass extinction event put biodiversity preservation on the same level as climate change in the list of public policy priorities (e.g. French Biodiversity Plan, 2018). The construction industry has already been asked to assess the carbon footprint of their new projects (e.g. future environmental regulations for new buildings, RE 2020). It has now also become necessary to have tools capable of measuring these projectsâ impacts on biodiversity. One can list five major risks facing biodiversity: habitats loss, global warming, pollution, resources overexploitation and invasive species introduction. These risks can have local causes - on the construction site of a project â or global ones. Both common and endangered species are affected by these risks. In this context, the scientific goal of this Ph.D. is to develop a reliable and robust methodology to evaluate interactions between biodiversity and urban systems. The operational goal is to design tooling that will support with the identification of the most favorable scenarios of construction for biodiversity. We propose a hybrid methodology to evaluate the interaction between biodiversity and urban system. It is based on a combination of ecology, Life Cycle Assessment (LCA) and data science. It takes into account the interactions between urban systems and in-situ (local) or ex-situ (global) biodiversity, as well as the five risks it is facing. The multi-scale process underlying the strategy involves a vertical development of the method (component, building, plot, district, territory). The main methodological developments consider:- The urban plantsâ life cycle: three data sets were structured according to the selected criteria for the proposed hybrid method: 1) Plants used in an urban setting, 2) Specific richness of floristic species for the habitats in the region Ile-de-France, 3) Environmental data for urban plants;- The construction project location specificities: a model, a database and a programming tool allow the calculation of a land use indicator, specific for the Ile-de-France region, with nearly 900 possible combinations of soil transformation;- The compatibility of the hybrid method with the methods and tools promoted by the regulatory bodies: linear regression models and a programming tool allow the calculation of ex-situ impacts from the outputs of environmental assessment software compatible with RE2020 (i.e. ELODIE)The methodâs operability to identify the levers of action was tested on a real case study, on the scale of a building, in the Ile-de-France region (EPA Marne project). Developments for the hybrid methodâs application to larger scales are proposed using specific tools suitable to each scale, such as BIM / CIM (Building / City Information Modeling) and a district scale evaluation software based on the RE2020 approach (ie UrbanPrint)
Dénaturation thermique du DNA de bactériophage lambda et interaction lambda DNA proflavine: Interactions lambda-DNA-proflavine
Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe
A study by electron microscopy of heat denaturation of λb2 phage DNA
SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Photodynamic action of methylated proflavine in λ+ and λb2 DNA
SCOPUS: ar.jinfo:eu-repo/semantics/publishe
The flexibility of a complex of DNA with methylated proflavine.
Journal Articleinfo:eu-repo/semantics/publishe
Biodiversity impact assessment of building's roofs based on Life Cycle Assessment methods
International audienceTo fight against the biodiversity loss and to take advantage of ecosystem services that nature can offer, urban planners integrate green spaces in urban projects. However to assess green spaces, attention is generally paid to local biodiversity (i.e. "in situ") which concerns the plot on which buildings are constructed. The biodiversity impacted outside the construction site (i.e. "ex situ") which concerns the extraction of materials, transportation and waste, is rarely associated to the project assessment. In this study, two endpoint Life Cycle Assessment (LCA) methods are applied: ReCiPe 2016 and Impact World + to assess a conventional roof and three different types of green roofs. As Life Cycle Inventory (LCI) data about urban plants are missing, we created new data to model the vegetation layer of green roofs by collecting information nearby plants nursery. This work shows that 1) extensive green roof generates the least biodiversity loss, 2) "ex situ" biodiversity is 10 times more impacted than "in situ" biodiversity, 3) the impact of the vegetation layer on the biodiversity loss is significant. LCA methods do not enable to cover all pressures threatening biodiversity and they also lack precision to assess "in situ" biodiversity. Nevertheless, their main strength is to consider "ex situ" biodiversity along the value chain of the studied systems. Coupling LCA with ecological expertise should improve the assessment by taking into account local specifi-cities and both negative and positive impacts of a system (e.g. "in situ" biodiversity gains with green roofs)