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The CRCTB and RRI IMPACT are pleased to invite you to a lecture by Professor Jason Woods (University of Cincinnati, Cincinnati Children's Hospital Medical Center).
Professor Woods, invited by Gaël Dournes, will give a presentation entitled: "Using modern MRI to achieve improved respiratory outcomes in pediatrics".
Contacts
RRI IMPACT congratulates Mireille Blanchard-Desce, member of RRI, CNRS research director at ISM, and winner of the Achille Le Bel 2024 prize awarded by the Société Chimique de France.
The prize is awarded by the SCF Board of Directors. It is awarded for internationally-recognized work that falls within the scope of the SCF's activities.
Mireille Blanchard-Desce entered the ENSJF in 1980, obtaining an agrégation in physical sciences and a doctorate in organic chemistry in 1989 (Université Pierre et Marie Curie) under the supervision of Jean-Marie Lehn. Mireille Blanchard-Desce has spent her entire professional career as a CNRS researcher since 198. At ENS Paris, she set up a young team to develop and optimize new chromophores for non-linear optics. During her thesis (under the supervision of Jean-Maire Lehn), she developed the first models of conductive molecular wires, then turned to the mechanisms of electron transfer in photosynthetic processes, which enabled her to direct her work towards molecular photonics and nanoscience. These studies led to the development of high-performance materials for electro-optical modulation.
In parallel with the covalent approach taken with organic nanodots, Mireille Blanchard-Desce was interested in an alternative route based on the self-assembly in water of multipolar, polarizable chromophoric motifs. Remarkably, this approach not only modulated optical properties (emission color, excitation response), but also surface properties (colloidal stability, interactions with cell membranes). In particular, these hyper-bright, modulable molecular nanoparticles have enabled two-photon microscopy angiography on small animals, tracking of individual nanoparticles in aqueous media, and two-color tracking within living cells.
Mireille Blanchard-Desce has been involved in research administration and management: unit director (UMR6510, Rennes) and team leader, elected for three terms to the CNRS Committee, coordinator and PI of two European ITN networks, numerous regional federative projects, member of the INC scientific council, among others. She plays an active role in the dissemination of knowledge through the supervision of over 30 theses and 20 post-doctoral fellows, teaching and publishing (editorial board of ChemPhysChem), expertise (ANR, LabEx, ERC, HCERES) and scientific mediation.
His work has been recognized by the CNRS, which awarded him the bronze medal in 1990 and the silver medal in 2008. She was awarded the Grand Prix Mergier-Bourdeix by the Académie des Sciences in 1999, the Palmes Académiques in 2009 and the Légion d'Honneur in 2012.
A member of the SCF, she has served on the board of the DCP and on the boards of the DCO and the French photo-physics, photochemistry and photo-sciences group.
To date, Mireille Blanchard-Desce's scientific output totals over 315 scientific articles, 1 book and 5 book chapters, 8 patents, 128 invited lectures at conferences and congresses, and around 100 seminars presented in academic and industrial settings.
LE RRI IMPACT congratulates Justine Couvez, doctoral student in the project and winner of the 2024 Mature Your PhD! competition. IMPACT félicite Justine Couvez, doctorante au sein du projet et lauréate du concours 2024 MAture Your PhD !
The Mature Your PhD+ competition is open to the entire Université de Bordeaux doctoral community in 2nd and 3rd year, including non-funded members. In addition to the Mature ton PhD program, which is open on a permanent basis, Mature you PhD+ is a way of recognizing your commitment. Co-constructed with the Graduate Research School and SATT AST, this is an annual competition (light pre-filing and pitch to a jury). For the 3 most convincing projects, you'll be awarded a 3-month fixed-term contract, during which you'll be able to devote yourself to this mission of innovation alongside your thesis work.
No call for the moment.
See you soon!
Presentation - 3D Semantic Segmentation of Airway Abnormalities on UTE-MRI with Reinforcement Learning on Deep Supervision, by Amel Imene Hadj Bouzid, Fabien Baldacci, Baudouin Denis De Senneville, Wadie Ben Hassen, Ilyes Benlala, Patrick Berger and Gaël Dournes, In ISBI 2025
Abstract
Cystic fibrosis (CF) monitoring traditionally relies on CT scans, which involve radiation exposure concerns. Ultra-short echo time (UTE) MRI has emerged as a promising radiation-free alternative for lung imaging. However, automated segmentation of CF lesions on UTE MRI has not been reported yet, mainly due to lower signal-to-noise ratio and contrast compared to CT. This study evaluates the feasibility of fully automated semantic segmentation of three main hallmarks of CF: bronchiectasis, bronchial wall thickening, and bronchial mucus. To address the challenges of low proton MRI signal and resolution, we propose a novel Reinforcement learning for deep Supervision adapted to nnU-Net (RiSeNet). This approach enhances the standard nnU-Net by dynamically ad-justing deep supervision weights during training through reinforcement learning. We compare RiSeNet against both the baseline nnU-Net and selected state-of-the-art architectures: SAMed and nnSAM for global context modeling, MedNeXt for large scale feature capture, and U-Mamba for efficient volu- metric processing. All models were evaluated using registered same-day CT-derived ground truth labels. Results demonstrate RiSeNet’s superior performance in both accuracy and efficiency when handling the unique challenges of UTE MRI segmentation.
Index Terms— Cystic Fibrosis, Semantic Segmentation, UTE MRI, Reinforcement Learning
Publication - Neuroprotective effects of lactate and ketone bodies in acute brain injury by Plourde, G., H. Roumes, L. Suissa, L. Hirt, E. Doche, L. Pellerin, A. K. Bouzier-Sore and H. Quintard, J Cereb Blood Flow Metab
Abstract :
The goal of neurocritical care is to prevent and reverse the pathologic cascades of secondary brain injury by optimizing cerebral blood flow, oxygen supply and substrate delivery. While glucose is an essential energetic substrate for the brain, we frequently observe a strong decrease in glucose delivery and/or a glucose metabolic dysregulation following acute brain injury. In parallel, during the last decades, lactate and ketone bodies have been identified as potential alternative fuels to provide energy to the brain, both under physiological conditions and in case of glucose shortage. They are now viewed as integral parts of brain metabolism. In addition to their energetic role, experimental evidence also supports their neuroprotective properties after acute brain injury, regulating in particular intracranial pressure control, decreasing ischemic volume, and leading to an improvement in cognitive functions as well as survival. In this review, we present preclinical and clinical evidence exploring the mechanisms underlying their neuroprotective effects and identify research priorities for promoting lactate and ketone bodies use in brain injury.
Keywords: Alternative brain fuels; TBI; brain metabolism; hypoxia; ketone bodies; lactate; neuroprotection; stroke.
Publication - Whole-brain T2 mapping with radial sampling and retrospective motion correction at 3T. by Corbin N, Trotier AJ, Anandra S, Kadalie E, Dallet L, Miraux S, and Ribot EJ, Magn Reson Med.
Abstract
Purpose: Several barriers prevent the use of whole-brain T2 mapping in routine use despite increasing interest in this parameter. One of the main barriers is the long scan time resulting in patient discomfort and motion corrupted data. To address this challenge, a method for accurate whole-brain T2 mapping with a limited acquisition time and motion correction capabilities is investigated.
Methods: A 3D radial multi-echo spin-echo sequence was implemented with optimized sampling trajectory enabling the estimation of intra-scan motion, subsequently used to correct the raw data. Motion corrected echo images are then reconstructed with linear subspace constrained reconstruction. Experiments were carried out on phantom and volunteers at 3T to evaluate the accuracy of the T2 estimation, the sensitivity to lesions and the efficiency of the correction on motion corrupted data.
Results: Whole-brain T2 mapping acquired in less than 7 min enabled the depiction of lesions in the white matter with longer T2. Data retrospectively corrupted with typical motion traces of pediatric patients highly benefited from the motion correction by reducing the error in T2 estimates within the lesions. All datasets acquired on seven volunteers, with deliberate motion, also showed that motion corrupted T2 maps could be improved with the retrospective motion correction both at the voxel level and the structure level.
Conclusion: A whole-brain T2 mapping sequence with retrospective intra-scan motion correction and reasonable acquisition time is proposed. The method necessitates advanced iterative reconstruction strategies but no additional navigator, external device, or increased scan time is required.
Keywords: T2 mapping; motion correction; radial sampling.