257 A novel polysaccharide-based porous scaffold for cell delivery into the infarcted heart

BackgroundCellular cardiomyoplasty has been proposed as an attractive strategy to repair myocardial damage. One of the crucial point is the optimal delivery strategy. In the present study, we examined the use of an implantable porous scaffold for promoting bone marrow-derived mesenchymal stem cells (MSCs) survival and functions in a rat model of acute myocardial infarction.Methods and ResultsCardiac patch was based on biodegradable polysaccharides porous scaffold. After ligation of the left anterior coronary artery, the fate of 1x106 GFP+ MSC administered either using cellularized scaffold implantation or direct injection was examined at 1 and 2 months. The number of residual GFP+ cells in the sample studied was estimated on the basis of the fluorescence emitted by a defined number of GFP+ cells used for calibration. Cellularized scaffold allowed a more efficient delivery and the difference with direct injection was significant at 2 months, with respectively 2100±1300×103 and 215±85x103 residual GFP+ cells (p<0.03). Cardiac tissue levels of matrix metalloproteinase-2 and -9 mRNA were similar whatever the administration conditions but a slight increase in the local production of vascular endothelial growth factor was observed at 2 months after patch implantation in comparison to direct injection (p<0.05). In animals having received MSC implemented on scaffold, clusters of GFP+ cells, mainly phenotypically consistent with immature MSC cells, were detected in the peri-infarct area. The increased survival using scaffold was not translated in an improved myocardial remodelling and functions with no significant difference in the LVEDD, LVESD, and FS between the 2 groups as in comparison with animals implanted with non cellularized scaffold.ConclusionsThese findings demonstrate that the implantation of cellularized grafts is safe and effective for delivering mesenchymal stem cells into damaged myocardium, and results in a better cellular engraftment compared to direct injection

Left bundle branch block-induced cardiomyopathy: Myth or reality?

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Magnetic behaviour of the MTbF6 fluoroterbates (M=Cd, Ca, Sr, (α/β)-Ba)

Neutron powder diffraction has been performed on the MTbF6 fluorides (M=Cd, Ca, Sr, (α/β)-Ba). Four of these fluorides (Cd, Ca, Sr, β-Ba) are built of a (pseudo-) tetragonal packing of [TbF6]2− chains and only differs by the chains relative orientations. Thus this series represents a valuable opportunity to evaluate the Tb4+-Tb4+ magnetic interactions. All the compounds displayed antiferromagnetic order (TN=2.70 K (Cd), 2.15 K (Ca), 2.60 K (Sr), 2.10 K (β-Ba)), except for the α form of BaTbF6. The crystal structure of this latter fluoroterbate has also been investigated by means of high-resolution neutron powder diffraction. From Neutron Powder Diffraction data, CdTbF6 and β-BaTbF6 magnetic structures were determined, together with the metamagnetic behaviour of β-BaTbF6 as a function of an external magnetic field. A tentative phase diagram is then given for β-BaTbF6. Advantage was taken of the polymorphism of the BaTbF6 fluoroterbate to analyse, on the basis of topological parameters such as bond distances and angles, the magnetic behaviour of its α and β forms. It was shown that superexchange interactions are present in β-BaTbF6, and that these interactions may also rule the magnetic behaviour of the other MTbF6 (M=Ca, Sr, Cd) tetravalent terbium fluorides

The Ce--Ni--Ge system: relationship between chemical composition and magnetic ordering

The investigation on Ce--Ni--Ge phase diagram indicates a relationship between the physical behavior of these ternary germanides and their chemical composition. Those with more than 50 % Ge-atomic percentage order antiferromagnetically, with Néel temperatures TN decreasing with Ge-content. The Ce-magnetic moment at 1.4 K, determined by neutron powder diffraction, also decreases with Ge-content. As for the ternary germanides rich in Ni (\geq 33%), they can be classified as intermediate valence compounds (CeNiGe, Ce3Ni4Ge4 and CeNi4.25Ge0.75) or heavy-fermions systems (CeNi2Ge2 and CeNi9Ge4)

The Ce--Ni--Ge system: relationship between chemical composition and magnetic ordering

The investigation on Ce--Ni--Ge phase diagram indicates a relationship between the physical behavior of these ternary germanides and their chemical composition. Those with more than 50 % Ge-atomic percentage order antiferromagnetically, with Néel temperatures TN decreasing with Ge-content. The Ce-magnetic moment at 1.4 K, determined by neutron powder diffraction, also decreases with Ge-content. As for the ternary germanides rich in Ni (\geq 33%), they can be classified as intermediate valence compounds (CeNiGe, Ce3Ni4Ge4 and CeNi4.25Ge0.75) or heavy-fermions systems (CeNi2Ge2 and CeNi9Ge4)

External validation of risk factors for malignant ventricular arrhythmias in lamin A/C mutation carriers

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Epidemiology of invasive fungal infections during induction therapy in adults with acute lymphoblastic leukemia: a GRAALL-2005 study.

International audienceLittle data have been published concerning invasive fungal infections during treatment of acute lymphoblastic leukemia (ALL). Patients included between May 2006 and October 2012 in the multicenter phase III trial for newly diagnosed ALL (GRAALL-2005) were retrospectively reviewed for the occurrence of IFI using the EORTC modified criteria. These patients did not routinely receive antifungal prophylaxis. Among 969 patients included (median age 47 years), 65 (6.7%) developed IFI during induction chemotherapy: 26 (3.3%) invasive aspergillosis (IA), 33 (3.4%) invasive candidiasis (IC) and six other IFI. For IA, the median time between induction therapy and IA diagnosis was 20 days. Diagnosis was probable in 22 cases and proven in four. Aspergillus antigen in serum was tested in all cases and positive in 24. Overall 12-week mortality after diagnosis of IA was 5/26 and attributable mortality related to the infection was 4/26 (15.4%). For IC, the median time between induction therapy and diagnosis was 19 days. Diagnosis was proven in 29 episodes. Candida albicans was the major pathogen in yeast infections (16/27). Overall 12-week mortality after diagnosis of IC was 8/33 (24.2%) and attributable mortality related to the infection was 7/33. The median delay between induction chemotherapy initiation and attributable death related to IC was 15 days. These findings may help to optimize the future management of ALL patients, and as in AML advocate systematic monitoring and the development of prophylactic or preemptive antifungal treatments