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International audience; Doping of transition metals within a semiconductor quantum dot (QD) has a high impact on the optical and magnetic properties of the QD. In this study, we report the synthesis of Mn 2+-doped Ag−In−Ga−Zn−S (Mn:AIGZS) QDs via thermolysis of a dithiocarbamate complex of Ag + , In 3+ , Ga 3+ , and Zn 2+ and of Mn(stearate) 2 in oleylamine. The influence of the Mn 2+ loading on the photoluminescence (PL) and magnetic properties of the dots are investigated. Mn:AIGZS QDs exhibit a diameter of ca. 2 nm, a high PL quantum yield (up to 41.3% for a 2.5% doping in Mn 2+), and robust photo-and colloidal stabilities. The optical properties of Mn:AIGZS QDs are preserved upon transfer into water using the glutathione tetramethylammonium ligand. At the same time, Mn:AIGZS QDs exhibit high relaxivity (r 1 = 0.15 mM −1 s −1 and r 2 = 0.57 mM −1 s −1 at 298 K and 2.34 T), which shows their potential applicability for bimodal PL/magnetic resonance imaging (MRI) probes.

Au début de la deuxième vague de COVID-19, le 7 novembre 2020, était organisé le séminaire « Questions d’éthique » au Lieu Unique à Nantes (France). La conférence du Pr. Axel Kahn était axée sur la perspective éthique des relations entre information et médias, chercheurs et essais cliniques, liberté individuelle et démocratie sanitaire, mais également l’urgence des soins, le tri des patients et le confinement. Partant du caractère indispensable de l’ « éthique en temps de crise », titre de sa conférence, il analyse sa pratique à travers le prisme de la liberté et de la responsabilité., At the beginning of the second wave of COVID-19, on November 7, 2020, the conference “Questions d’éthique” was held at the Lieu Unique in Nantes (France). Prof. Axel Kahn’s presentation focused on the ethical perspective of the relations between information and media, researchers and clinical trials, individual liberty and health democracy, but also the urgency of care, patient triage and confinement. Starting from the indispensable character of “ethics in times of crisis”, the title of his talk, he analyzed his practice through the prism of liberty and responsibility.

International audience; Peptide-based hydrogels are physical gels formed through specific supramolecular self-assembling processes, leading to ordered nanostructures which constitutes the water entrapping scaffold of the soft material. Thanks to the inherent properties of peptides, these hydrogels are highly considered in the biomedical domain and open new horizons in terms of application in advanced therapies and biotechnologies. The use of one, and only one, native peptide to formulate a gel is by far the most reported approach to design such materials, but suffers from several limitations, including in terms of mechanical properties. To improve peptide-based hydrogels interest and give rise to innovative properties, several strategies have been proposed in the recent years, and the development of multicomponent peptide-based hydrogels appears as a promising and relevant strategy. Indeed, mixing two or more compounds to develop new materials is a much-used approach that has proven its effectiveness in a wide variety of domains, including polymers, composites and alloys. While still limited to a handful of examples, we would like to report herein on the formulation and the comprehensive study of multicomponent hybrid DNA-nucleobase/peptide-based hydrogels using a multiscale approach based on a large panel of analytical techniques (i.e., rheometry, proton relaxometry, SAXS, electronic microscopy, infrared, circular dichroism, fluorescence, Thioflavin T assays). Among the six multicomponent systems studied, the results highlight the synergistic role of the presence of the two complementary DNA-nucleobases (i.e., adenine/thymine and guanine/cytosine) on the coassembling process from structural (e.g., morphology of the nanoobjects) to physicochemical (e.g., kinetics of formation, fluorescence properties) and mechanical properties (e.g., stiffness, resistance to external stress). All the data confirm the relevance of the multicomponent peptide-based approach in the design of innovative hydrogels and bring another brick in the wall of the understanding of these complex and promising systems.

Objectif : Évaluer la prévalence de la plainte cognitive chez des personnes ayant été traitées pour un lymphome. Matériel et méthode : Questionnaire diffusé auprès des participants de la Journée mondiale des lymphomes, en septembre 2017 et février 2018. Résultats : Soixante-deux pour cent des participants (n = 396) rapportaient une plainte cognitive, et 39 % l’attribuaient aux traitements oncologiques reçus. Cinquantequatre pour cent d’entre eux auraient souhaité bénéficier de soins de support adaptés. Conclusion : Les difficultés cognitives à la suite des traitements oncologiques doivent être mieux connues des professionnels de santé afin de proposer des soins de support adaptés.