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Saint-Nazaire-les-Eymes, France

Dimastromatteo J.,French Institute of Health and Medical Research | Dimastromatteo J.,Joseph Fourier University | Dimastromatteo J.,ERAS Labo | Riou L.M.,French Institute of Health and Medical Research | And 22 more authors.
Journal of Nuclear Cardiology | Year: 2010

Background: Myocardial angiogenesis following reperfusion of an infarcted area may impact on patient prognosis and pro-angiogenic treatments are currently evaluated. The non-invasive imaging of angiogenesis would therefore be of potential clinical relevance in these settings. 99mTc-RAFT-RGD is a novel 99mTc-labeled tracer that targets the αvβ 3 integrin. Our objective was to determine whether this tracer was suitable for myocardial angiogenesis imaging. Methods and Results: A rat model of reperfused myocardial infarction was employed. Fourteen days following reperfusion, the animals were injected with 99mTc-RAFT-RGD or with its negative control 99mTc-RAFT-RAD. Fourteen animals were dedicated to autoradiographic imaging, infarct staining, and gamma-well counting of myocardial activity. In vivo dual-isotope pinhole SPECT imaging of 201Tl and 99mTc-RAFT-RGD or 99mTc-RAFT-RAD was also performed in 11 additional animals. Neovessels were observed by immunostaining in the infarcted and peri-infarct areas. 99mTc-RAFT- RGD infarct-to-normal ratios by gamma-well counting and ex vivo imaging (2.5 ± 0.6 and 4.9 ± 0.9, respectively) were significantly higher than those of 99mTc-RAFT-RAD (1.7 ± 0.2 and 2.2 ± 0.4, respectively, P < .05). The infarcted area was readily visible in vivo by SPECT with 99mTc-RAFT-RGD but not with 99mTc-RAFT-RAD (infarct-to-normal zone activity ratio, 2.5 ± 0.6 and 1.7 ± 0.4, respectively, P < .05). Conclusion: 99mTc-RAFT-RGD allowed the experimental in vivo molecular imaging of myocardial angiogenesis. © 2010 American Society of Nuclear Cardiology.

Mabrouk W.,Tunis el Manar University | Mabrouk W.,University of Carthage | Mabrouk W.,CNRS Process and Engineering in Mechanics and Materials Laboratory | Ogier L.,ERAS Labo | And 4 more authors.
Desalination and Water Treatment | Year: 2015

Two new types of proton exchange membranes used in proton exchange membrane fuel cell (PEMFC) were synthesized from sulfochlorinated polyethersulfone (PES (polyarylethersulfone)–SO2Cl). One, called S-PESB, was obtained by grafting butylphenol in an amount of 0.3 equivalent per monomer unit. The second (S-PESTD) was prepared by cross-linking with 0.1 equivalent of 4,7,10-trioxa-1,13-tridecandiamine. Analysis of thermal properties (thermogravimetric analysis and DSA) and mechanical testing (dynamical and thermomechanical analysis) of the two membranes showed a significant improvement in comparison with unmodified polyethersulfone sulfonic acid (S-PES). Thus, a significant lowering of the glass transition temperature was observed. In addition, a comparative study carried out with the commercial Nafion® membrane gave very similar values of ionic conductivity and a high selectivity of proton transport. A preliminary electrochemical study of membrane/electrode assembly has shown that the elaborated membranes are promising in PEMFC application. Power densities obtained with cross-linked S-PESTD were superior to those of commercial Nafion®, while S-PESB led to comparable values. © 2015 Balaban Desalination Publications. All rights reserved.

Grauzam S.,Joseph Fourier University | Grauzam S.,CNRS Complex Medical Engineering Laboratory | Henri M.,French Institute of Health and Medical Research | Henri M.,Joseph Fourier University | And 11 more authors.
IRBM | Year: 2011

A new technique of insulin resistance assessment, using nuclear imaging, was developed. On a model of experimental myocardial infarction in rats, our results indicate a significant phenomenon of cardiac insulin resistance seven days after ischaemia. This study demonstrates the sensitivity of the technique for measuring insulin resistance by nuclear imaging. © 2011 Elsevier Masson SAS. All rights reserved.

Delhorbe V.,Cergy-Pontoise University | Thiry X.,CNRS Physical Eletrochemistry Materials and Interfaces Lab | Cailleteau C.,CEA Grenoble | Mourier E.,University Claude Bernard Lyon 1 | And 11 more authors.
Journal of Membrane Science | Year: 2012

The purpose of this study has been to develop new proton-exchange membranes based on semi-interpenetrating polymer network (semi-IPN) architectures for application in polymer electrolyte fuel cells. A series of semi-IPNs combining a fluorinated hexane network and a linear sulfonated poly(aryl ether ether ketone) (SPEEK) has been obtained by varying the SPEEK content from 50 to 80. wt.%. A telechelic functionalized acrylate oligomer was obtained by acrylation of α,ω-fluorinated hexanediol, while SPEEK was synthesized by polycondensation of sulfonated difluorobenzophenone with the bisphenol 6F. These semi-IPN membranes have been characterized by infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and small-angle X-ray scattering. A semi-IPN containing 60. wt.% SPEEK has been tested as a fuel cell membrane. © 2011 Elsevier B.V.

Delhorbe V.,Cergy-Pontoise University | Reijerkerk S.R.,CEA Grenoble | Cailleteau C.,CNRS Structure and Properties of Molecular Architectures Laboratory | Bathfield M.,Charles Gerhardt Institute | And 9 more authors.
Journal of Membrane Science | Year: 2013

Original membranes based on an interpenetrating polymer network (IPN) architecture combining a poly(2-acrylamido-2-methyl-1-propane sulfonic acid) (AMPS) network and a fluorinated network were synthesized. The AMPS weight compositions were varied from 50 to 70. wt%. The first network was achieved by radical copolymerization of AMPS with a fluorinated telechelic diacrylate while the second one was obtained by photoinitiated cationic copolymerization of telechelic fluorinated diepoxide with trimethylol propane triglycidyl ether. The morphologies of these different IPNs were deduced from small-angle X-ray scattering (SAXS) spectra and dynamic thermomechanical analysis (DMTA). The main functional properties related to their use as proton exchange membrane in fuel cells were quantified, such as water vapor sorption, liquid water uptake (22-59. wt%), proton conductivity (1-63. mS/cm), gas permeability (0.06 and 0.80 barrer for dry oxygen and hydrogen, respectively), and oxidative and thermal stabilities. More precisely, the effects of the ionic exchange capacity (IEC) varying from 1.73 to 2.43. meq/g and the cross-linking density of the conducting phase on the morphology and the properties of IPN membranes were studied in detail. Finally, these IPN membranes were tested as fuel cell membrane and a correlation between the ex-situ and in-situ characterizations was established. © 2012 Elsevier B.V.

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