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In vivo stability of <sup>211</sup>At-radiopharmaceuticals: on the impact of halogen bond formation
No full textInternational audienceAt, when coupled to a targeting agent, is one of the most promising radionuclides for therapeutic applications. The main labelling approach consists in the formation of astatoaryl compounds, which often show a lack of in vivo stability. The hypothesis that halogen bond (XB) interactions with protein functional groups initiate a deastatination mechanism is investigated through radiochemical experiments and DFT modelling. Several descriptors agree on the known mechanism of iodoaryl substrates dehalogenation by iodothyronine deiodinases, supporting the higher in vivo dehalogenation of Nsuccinimidyl 3-[ 211 At]astatobenzoate (SAB) conjugates in comparison with their iodinated counterparts. The guanidinium group in 3-[ 211 At]astato-4-guanidinomethylbenzoate (SAGMB) prevents the formation of At-mediated XBs with the selenocysteine active site in iodothyronine deiodinases. The initial step of At-aryl bond dissociation is inhibited, elucidating the better in vivo stability of SAGMB conjugates compared with those of SAB. The impact of astatine's ability to form XB interactions on radiopharmaceutical degradation may not be limited to the case of aryl radiolabeling
Total Absorption Gamma-ray Spectroscopy for applied and fundamental physics
No full textInternational audienc
Preliminary results of the theranostic Sc cyclotron proton-induced production with enriched Ti, Ti and Ti targets
No full textInternational audienceThe scientific community interest in the production of the theranostic 47Sc is due to its medical favourable decay characteristics suitable for both SPECT imaging and therapeutic purposes. Considering the SPES cyclotron, this work is focused on the measurement of the 48/49/50Ti(p,x)47Sc and 46Sc cross sections up to 70 MeV. In fact, 46Sc is the main co-produced contaminant, since it has a longer half-life than the theranostic 47Sc. Enriched 48/49/50Ti powder were deposited on aluminum backing by using the HIVIPP technique and the obtained targets were characterized by Elastic Back Scattering at the INFN-LNL. Experimental data are compared with the scarce literature and the TALYS results, obtained using the default parameters
Insights on the carbon footprint of radiotherapy in France
No full textInternational audienceAchieving a net zero emissions scenario will require a 4-5 fold decrease of carbon emissions in the coming years. The carbon footprint of radiation therapy has not been specifically studied to date. In this review we summarize the content of the carbon footprint dedicated session in the SFRO congress. We discuss the French healthcare system carbon footprint and its major drivers and our work on the estimation of the carbon footprint of external beam radiation therapy in the French setting. We developed a dedicated methodology to estimate the carbon footprint related to radiation therapy treatments, and describe the main drivers of emissions based on a single center as an example, namely patient’s rides, accelerators acquisition and maintenance and data storage. Based on the carbon footprint calculated in our centers, we propose mitigation strategies and an estimation of their respective potential. Our results may be extrapolated to other occidental settings by adapting emission factors (kgCO2/item or euro) to other national settings. EBRT has a major carbon footprint that may be mitigated in many ways that may impact how radiation therapy treatments are delivered, as well as the national organization of the radiotherapy sector. This needs to be taken into account when thinking about the future of radiotherapy.Le système de santé français est responsable de 8% de l’empreinte carbone nationale. La réalisation d'un scénario neutre en émission nécessiterait de diviser par 4 ou 5 les émissions carbonées actuelles dans les années à venir. Cependant l’empreinte carbone de la radiothérapie n'a pas été spécifiquement étudiée à ce jour.Dans cette revue, nous résumons le contenu de la session du congrès de la SFRO dédiée à la sobriété énergétique et à l'empreinte carbone de la radiothérapie. Nous discutons de l'empreinte carbone du système de santé français et de nos travaux sur l'estimation de l'empreinte carbone de la radiothérapie externe. Nous avons développé une méthodologie dédiée pour estimer l'empreinte carbone liée aux traitements de radiothérapie et ainsi estimé les principales sources d'émissions, à savoir les trajets des patients et des personnels, la fabrication et la maintenance des accélérateurs et le stockage des données. Sur la base de l'empreinte carbone calculée dans nos centres, nous proposons des stratégies de réduction et une estimation de leur potentiel respectif. Nos résultats peuvent être extrapolés à d'autres paramètres internationaux en adaptant les facteurs d'émission (kgCO2/article ou euro) à d'autres paramètres nationaux.La radiothérapie externe a une empreinte carbone majeure qui peut être diminuée de plusieurs manières, notamment en modifiant le fractionnement des traitements. Ces modifications auraient un impact important sur la manière dont les traitements de radiothérapie sont dispensés, ainsi que sur l'organisation des soins en radiothérapie. Il faut donc en tenir compte dans la réflexion sur l'avenir de la radiothérapie
production at NLO with a scale-dependent color-evaporation model
No full textInternational audienceNearly ten years ago, Kang, Ma, Qiu, and Sterman derived an evolution equation for a pair fragmenting into a quarkonium. In this study we explore the consequence of this evolution for the color-evaporation model, focusing on transverse-momentum () distributions in proton-proton collisions. We show that, as expected, it softens the spectrum obtained by fixed-order calculations. While next-to-leading-order calculations strongly overestimate data at large , ours, including the (approximate) evolution and next-to-leading-order cross sections computed with Madgraph, are in good agreement with experiments. Since our study with the color-evaporation model shows a significant effect of the evolution at large , a determination of scale-dependent long-distance-matrix elements of non-relativistic QCD could be necessary. To describe data at small and intermediate , we use the -factorization approach, and we argue that quarkonia data could help constrain unintegrated parton densities
Perturbative QCD concerning light and heavy flavor in the EPOS4 framework
No full textInternational audienceWe recently introduced new concepts, implemented in EPOS4, which allow to consistently accommodate factorization and saturation in high energy proton-proton and nucleus-nucleus collisions, in a rigorous parallel scattering framework. EPOS4 has a modular structure and in this paper, we present in detail how the "single scattering module" (the main EPOS4 building block) is related to perturbative QCD, and how these calculations are performed, with particular care being devoted to heavy flavor contributions. We discuss similarities and differences compared to the usual pQCD approach based on factorization