Publications by authors named "Cécile Courrèges"

5 Publications

  • Page 1 of 1

AES and ToF-SIMS combination for single cell chemical imaging of gold nanoparticle-labeled .

Chem Commun (Camb) 2021 Jun;57(44):5446-5449

Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, Institut des Sciences Analytiques et Physico-Chimie Pour l'Environnement et les matériaux (IPREM), 2 avenue du Président Angot, 64000 Pau, France.

A chemical fingerprint of the Escherichia coli cell surface labeled by gelatin coated gold nanoparticles was obtained by combining Auger Electron Spectroscopy (AES) for single cell level chemical images, and Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS) Tandem MS for unambiguous molecular identification of co-localized species.
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http://dx.doi.org/10.1039/d1cc01211hDOI Listing
June 2021

[email protected] Functional Nanoparticle-Driven Rod-Coil Diblock Copolymer Self-Assembly.

Langmuir 2019 Dec 10;35(51):16925-16934. Epub 2019 Dec 10.

CNRS/Université de Pau et des Pays de l'Adour/E2S UPPA , IPREM CNRS-UMR 5254 Hélioparc , 2 Avenue Président Angot , 64053 Pau Cedex 9, France.

Herein, a novel strategy to overcome the influence of π-π stacking on the rod-coil copolymer organization is reported. A diblock copolymer poly(3-hexylthiophene)--poly(ethylene glycol methyl ether methacrylate) (P3HT--PEGMA) was synthesized by the Huisgen cycloaddition, so-called "click chemistry", combining the PEGMA and P3HT blocks synthesized by atom transfer radical polymerization and Kumada catalyst transfer polymerization, respectively. Using a dip-coating process, we controlled the original film organization of the diblock copolymer by the crystallization of the P3HT block via π-π stacking. The morphology of the P3HT--PEGMA films was influenced by the incorporation of gold nanoparticles (GNPs) coated by poly(ethylene glycol) ligands. Indeed, the crystalline structuration of the P3HT sequence was counterbalanced by the addition in the film of gold nanoparticles finely localized within the copolymer PEGMA matrix. Transmission electron microscopy and time-of-flight secondary ion mass spectrometry analysis validated the GNP homogeneous localization into the compatible PEGMA phase. Differential scanning calorimetry showed the rod block crystallization disruption. A morphological transition of the self-assembly is observed by atomic force microscopy from P3HT fibrils into out-of-plane cylinders driven by the nanophase segregation.
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http://dx.doi.org/10.1021/acs.langmuir.9b02744DOI Listing
December 2019

Structural evidence of a phosphoinositide-binding site in the Rgd1-RhoGAP domain.

Biochem J 2017 09 20;474(19):3307-3319. Epub 2017 Sep 20.

Université de Bordeaux, Chimie et Biologie des Membranes et des Nano-objets, CNRS UMR 5248, Allée Geoffroy Saint Hilaire, 33600 Pessac Cedex, France

Phosphoinositide lipids recruit proteins to the plasma membrane involved in the regulation of cytoskeleton organization and in signalling pathways that control cell polarity and growth. Among those, Rgd1p is a yeast GTPase-activating protein (GAP) specific for Rho3p and Rho4p GTPases, which control actin polymerization and stress signalling pathways. Phosphoinositides not only bind Rgd1p, but also stimulate its GAP activity on the membrane-anchored form of Rho4p. Both F-BAR (F-BAR FCH, and BAR) and RhoGAP domains of Rgd1p are involved in lipid interactions. In the Rgd1p-F-BAR domain, a phosphoinositide-binding site has been recently characterized. We report here the X-ray structure of the Rgd1p-RhoGAP domain, identify by NMR spectroscopy and confirm by docking simulations, a new but cryptic phosphoinositide-binding site, comprising contiguous A1, A1' and B helices. The addition of helix A1', unusual among RhoGAP domains, seems to be crucial for lipid interactions. Such a site was totally unexpected inside a RhoGAP domain, as it was not predicted from either the protein sequence or its three-dimensional structure. Phosphoinositide-binding sites in RhoGAP domains have been reported to correspond to polybasic regions, which are located at the unstructured flexible termini of proteins. Solid-state NMR spectroscopy experiments confirm the membrane interaction of the Rgd1p-RhoGAP domain upon the addition of PtdIns(4,5)P and indicate a slight membrane destabilization in the presence of the two partners.
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http://dx.doi.org/10.1042/BCJ20170331DOI Listing
September 2017

Enhanced electrochemical performance of Lithium-ion batteries by conformal coating of polymer electrolyte.

Nanoscale Res Lett 2014 2;9(1):544. Epub 2014 Oct 2.

Aix-Marseille Université, CNRS, LP3 UMR 7341, F-13288, Marseille Cedex 9, France ; Aix-Marseille Université, CNRS, MADIREL UMR 7246, F-13397, Marseille Cedex 20, France.

This work reports the conformal coating of poly(poly(ethylene glycol) methyl ether methacrylate) (P(MePEGMA)) polymer electrolyte on highly organized titania nanotubes (TiO2nts) fabricated by electrochemical anodization of Ti foil. The conformal coating was achieved by electropolymerization using cyclic voltammetry technique. The characterization of the polymer electrolyte by proton nuclear magnetic resonance ((1)H NMR) and size-exclusion chromatography (SEC) shows the formation of short polymer chains, mainly trimers. X-ray photoelectron spectroscopy (XPS) results confirm the presence of the polymer and LiTFSI salt. The galvanostatic tests at 1C show that the performance of the half cell against metallic Li foil is improved by 33% when TiO2nts are conformally coated with the polymer electrolyte.
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http://dx.doi.org/10.1186/1556-276X-9-544DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4194452PMC
October 2014

[The National Health Agency: the challenge of a unified national program rejecting technocratic and centralized approaches].

Sante Publique 2012 May-Jun;24(3):229-40

Institut National du Cancer - 52 Avenue André Morizet - 92513 Boulogne-Billancout.

The creation of Regional Health Agencies precipitated the need for an overhaul of national health policy management. The National Steering Committee created as part of the HPST law is only a step in the right direction. We need to go beyond the coordination of national policy-makers in order to develop and implement an effective health policy. The creation of a National Health Agency (ANS) is generally considered to be the best way to develop a national steering mechanism capable of developing and implementing a global health policy. The purpose of this new body is not to act as a "super health agency" encompassing all existing health agencies. Rather, the ANS should aim to be an instrument of regulation acting on health care organization and funding and the quality and effectiveness of health care practices. In this sense, its role is to bring together state services and National health insurance services. However, there are two different conceptions of the agency's role ? as an autonomous technical entity based on the current model of the CNAMTS or as a body under the authority of the Ministry of Health. In both cases, the ANS may serve to increase the emphasis on technocratic and centralized approaches to health management. An intermediate solution between the ANS and the current status quo would involve increasing the authority of the Secretary-General of the Social Ministries over the central bodies of the Ministry of Health, the National health insurance services and the National Solidarity Fund for Autonomy. As part of this mission, the Secretary-General would oversee a specific body with national jurisdiction. While integrating a more coherent national policy as well as maintaining the decision-making bodies of the current administrative system, this intermediate solution would help to avoid a radical restructuring of existing national institutions at a time when current challenges in the area of population health require immediate attention.
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December 2012