Exon skipping as a therapeutic strategy applied to an RYR1 mutation with pseudo-exon inclusion causing a severe core myopathy.

International audienceCentral core disease is a myopathy often arising from mutations in the type 1 ryanodine receptor (RYR1) gene, encoding the sarcoplasmic reticulum calcium release channel RyR1. No treatment is currently available for this disease. We studied the pathological situation of a severely affected child with two recessive mutations, which resulted in a massive reduction in the amount of RyR1. The paternal mutation induced the inclusion of a new in-frame pseudo-exon in RyR1 mRNA that resulted in the insertion of additional amino acids leading to the instability of the protein. We hypothesized that skipping this additional exon would be sufficient to restore RyR1 expression and to normalize calcium releases. We therefore developed U7-AON lentiviral vectors to force exon skipping on affected primary muscle cells. The efficiency of the exon skipping was evaluated at the mRNA level, at the protein level, and at the functional level using calcium imaging. In these affected cells, we observed a decreased inclusion of the pseudo-exon, an increased RyR1 protein expression, and a restoration of calcium releases of normal amplitude either upon direct RyR1 stimulation or in response to membrane depolarization. This study is the first demonstration of the potential of exon-skipping strategy for the therapy of central core disease, from the molecular to the functional level

Lire avec son corps : l’écoute de soi lisant

International audienceEn ce début du XXI e siècle, la recherche sur la réception des oeuvres – littéraires et plastiques – se caractérise par un changement de paradigme. Les investigations des chercheurs concernent moins l'oeuvre elle-même et le discours analytique qu'elle suscite que la relation intime qui se noue dans la rencontre entre l'oeuvre et le sujet. De fait, la tradition scolaire et universitaire d'une lecture désincarnée, orpheline, où domine l'analyse formelle est décriée de longue date par la critique : tendance à la généralisation qui ruine l'unicité du texte 1 (Riffaterre), « décodage rationalisant plus ou moins compliqué » 2 (Picard), rigidité d'une « petite technique pédagogique […] desséchante » 3 (Compagnon), ensemble de remarques savantes qui inspirent à J.-M. Delacomptée 4 le voeu suivant : « un peu moins de science, un peu plus de conscience » ! Sous sa forme d'exercice codifié prônant une observation objective des formes textuelles, la lecture littéraire apparaît comme un malentendu, comme l'échec programmé d'une rencontre dont le texte et le lecteur font les frais. Mais, c'est avant tout de la mise hors-jeu du sujet lecteur que témoigne cette instrumentalisation 5. Désormais, c'est donc le sujet lecteur et ce qui le constitue qui retiennent l'attention des chercheurs. On s'intéresse à ses affects, à sa réception singulière, à sa créativité. Le colloque toulousain de 2008 consacré au « texte du lecteur » et à ce qu'il révèle de l'activité lectrice au coeur de la lecture a exploré les modalités d'élaboration des textes de lecteurs et le matériau dont ils sont faits : fragments verbaux, rythmes, images mentales, éléments fantasmatiques.... Aujourd'hui, la réflexion s'engage sur les émotions et leur rôle cardinal dans la réception des oeuvres littéraires ; Alexandre Gefen, par exemple, a organisé à Bordeaux 3 ces deux dernières années un séminaire « Émotions de la littérature » ; à présent, il lance un programme de recherche prévoyant la réalisation d'un Dictionnaire des émotions. Cet intérêt contemporain pour les émotions n'est pas spécifique au champ littéraire. Il est entre autres partagé par les historiens qui organisent en juin prochain, un colloque L'émotion de l'espace privé à l'espace public, XIX e , XXI e siècles dont certaines problématiques intéressent..

Draft genomes and phenotypic characterization of Tisochrysis lutea strains. Toward the production of domesticated strains with high added value

Tisochrysis lutea is a microalga species currently used in aquaculture as a feed for shellfish, oysters and shrimps. It also has many other potential industrial applications, such as the production of neutral lipids for biofuels or the production of ω-3 fatty acids for nutraceuticals (human food complements). To efficiently exploit the potential of this microalga, however, higher lipid productivities are needed. To this end, improvement programs need to be developed and optimized. The diversity of strains available in microalgae has not yet been exploited in such improvement programs. In this study, the intra-strain diversity was observed and exploited to increase neutral lipid productivity. New clonal strains with higher neutral lipid productivity were successfully selected. The best clonal strain selected accumulated 520% more triacylglycerols, with a similar growth rate to the wild-type strain in continuous light and nitrogen starvation conditions. In a photoperiod culture condition, this clonal stain also accumulated 84% more storage lipids and 30% less carbohydrates, compared to the wild-type strain. This clonal strain thus had a higher productivity which is of great interest for feed or biofuel applications. This study also focused on identifying the genomic mechanisms responsible for the improvements in these clonal strains. With this objective, the genome of Tisochrysis lutea was sequenced for the first time. It is the third genome of a Haptophyte microalga sequenced so far. Different genetic polymorphisms were identified between the sequenced genomes of the wild-type strain and clonal strains. Activity of transposable elements seems to have been involved in the genome reshuffling obtained through the improvement program. The contribution of transposable elements to the adaptive capacity of microalgae remains to be demonstrated

Le transfert de connaissances à travers la collaboration chercheurs-décideurs. Retour d'expériences

National audienceIntroduction :En France, pour renforcer les liens entre les chercheurs et les décideurs au sein des territoires, de récentes propositions ont été faites en santé publique en faveur du transfert de connaissances (TC). Malgré des collaborations déjà existantes entre ces acteurs, le TC est encore peu étudié. Afin de caractériser les conditions facilitantes ou limitantes du TC dans de tels dispositifs, une investigation, de type exploratoire, a été menée dans deux régions françaises. L’objectif de cette communication est de présenter ses résultats.Méthode :Des entretiens non-directifs, individuels ou collectifs, ont été réalisés d’avril à juin 2014 avec des chercheurs et des décideurs institutionnels et politiques. Les personnes rencontrées exploraient elles-mêmes les interrogations possibles concernant les conditions du transfert de connaissances entre chercheurs et décideurs au niveau local ou régional.Résultats :15 chercheurs et 14 décideurs ont été rencontrés. Les chercheurs perçoivent le TC comme (1) une opportunité de construire une relation avec les décideurs, (2) un processus permettant la mise en commun de connaissances pour développer une culture partagée favorable à l’innovation locale, et (3) un dispositif à part entière, un espace d’échanges facilitant la création d’une dynamique de réseau durable. Concernant les décideurs, quatre conditions ont été soulevées pour faciliter le TC : (1) le caractère pragmatique de la recherche, qui doit être utile et ancrée dans leur contexte, (2) la présence de facilitateurs et de leaders, (3) des relations de qualité et pérennes, basées sur le respect et la confiance, et (4) les ressources disponibles sur le territoire et le contexte institutionnel.Conclusion :Cette phase exploratoire nous a permis de mieux appréhender le transfert de connaissances sur les plans conceptuel et opérationnel. Les constats mettent en lumière les conditions relatives aux fonctions informationnelles, relationnelles et systémiques du TC présentées dans les écrits scientifiques

Crystallization, microstructure and mechanical properties of transparent glass-ceramic.

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STING agonist diABZI induces PANoptosis and DNA mediated acute respiratory distress syndrome (ARDS)

International audienceAbstract Stimulator of interferon genes (STING) contributes to immune responses against tumors and may control viral infection including SARS-CoV-2 infection. However, activation of the STING pathway by airway silica or smoke exposure leads to cell death, self-dsDNA release, and STING/type I IFN dependent acute lung inflammation/ARDS. The inflammatory response induced by a synthetic non-nucleotide-based diABZI STING agonist, in comparison to the natural cyclic dinucleotide cGAMP, is unknown. A low dose of diABZI (1 µg by endotracheal route for 3 consecutive days) triggered an acute neutrophilic inflammation, disruption of the respiratory barrier, DNA release with NET formation, PANoptosis cell death, and inflammatory cytokines with type I IFN dependent acute lung inflammation. Downstream upregulation of DNA sensors including cGAS, DDX41, IFI204, as well as NLRP3 and AIM2 inflammasomes, suggested a secondary inflammatory response to dsDNA as a danger signal. DNase I treatment, inhibition of NET formation together with an investigation in gene-deficient mice highlighted extracellular DNA and TLR9, but not cGAS, as central to diABZI-induced neutrophilic response. Therefore, activation of acute cell death with DNA release may lead to ARDS which may be modeled by diABZI. These results show that airway targeting by STING activator as a therapeutic strategy for infection may enhance lung inflammation with severe ARDS

Prenatal exposure to persistent organic pollutants and body mass index trajectories from birth to age 12

International audienceBACKGROUND AND AIM[|]Several studies have explored the association between prenatal exposure to persistent organic pollutants (POPs) and body mass index (BMI) at a given age but very few have evaluated the dynamic of growth across ages. Our objective was to study the associations between prenatal exposure to multiple POPs and growth BMI trajectories from birth to adolescence.[¤]METHOD[|]This study included 430 mother-child pairs enrolled in the PELAGIE cohort (France). Polychlorinated biphenyls (PCBs), organochlorine pesticides (OCs), and per- and polyfluorinated substances (PFASs) were measured in cord blood. Latent class growth model was used to identify BMI z-score (zBMI) trajectories. Multinomial regressions evaluated the associations between each POP and the resulting zBMI trajectories, as well as Quantile G-computation to evaluate POP mixture effects. All analyses were stratified by sex and adjusted for confounders.[¤]RESULTS[|]Four classes of zBMI trajectories were identified and the “average zBMI at birth and lower zBMI up to age 12” trajectory was considered as the reference. In single-exposure models, higher exposure to beta-hexachlorocyclohexane (b-HCH) was associated with a higher odds of following the “higher zBMI from birth to age 12” trajectory (OR=1.5 [1.1;2.1]). In girls, higher exposure to all PCBs was associated with higher odds of following the trajectory “lower zBMI at birth with accelerated zBMI gain in early childhood before stabilization up to age 12”; this association was also observed in the mixture analysis (OR=1.2 [1.0;1.5]). In boys, higher exposure to some PFASs was associated with higher odds of following the “higher zBMI from birth to adolescence” trajectory and lower odds of following the “lower zBMI from birth to adolescence” trajectory.[¤]CONCLUSIONS[|]Prenatal exposure to POPs may be associated with some specific growth dynamics, known as risk factors for adult cardiovascular health

The influence of natural dissolved organic matter on herbicide toxicity to marine microalgae is species-dependent

Microalgae, which are the foundation of aquatic food webs, may be the indirect target of herbicides used for agricultural and urban applications. Microalgae also interact with other compounds from their environment, such as natural dissolved organic matter (DOM), which can itself interact with herbicides. This study aimed to evaluate the influence of natural DOM on the toxicity of three herbicides (diuron, irgarol and S-metolachlor), singly and in ternary mixtures, to two marine microalgae, Chaetoceros calcitrans and Tetraselmis suecica, in monospecific, non-axenic cultures. Effects on growth, photosynthetic efficiency (Ф’M) and relative lipid content were evaluated. The chemical environment (herbicide and nutrient concentrations, dissolved organic carbon and DOM optical properties) was also monitored to assess any changes during the experiments. The results show that, without DOM, the highest irgarol concentration (I0.5: 0.5 mg L−1) and the strongest mixture (M2: irgarol 0.5 μg L−1 + diuron 0.5 μg L−1 + S-metolachlor 5.0 μg L−1) significantly decreased all parameters for both species. Similar impacts were induced by I0.5 and M2 in C. calcitrans (around −56% for growth, −50% for relative lipid content and −28% for Ф’M), but a significantly higher toxicity of M2 was observed in T. suecica (−56% and −62% with I0.5 and M2 for growth, respectively), suggesting a possible interaction between molecules. With DOM added to the culture media, a significant inhibition of these three parameters was also observed with I0.5 and M2 for both species. Furthermore, DOM modulated herbicide toxicity, which was decreased for C. calcitrans (−51% growth at I0.5 and M2) and increased for T. suecica (-64% and −75% growth at I0.5 and M2, respectively). In addition to the direct and/or indirect (via their associated bacteria) use of molecules present in natural DOM, the characterization of the chemical environment showed that the toxic effects observed on microalgae were accompanied by modifications of DOM composition and the quantity of dissolved organic carbon excreted and/or secreted by microorganisms. This toxicity modulation in presence of DOM could be explained by (i) the modification of herbicide bioavailability, (ii) a difference in cell wall composition between the two species, and/or (iii) a higher detoxification capacity of C. calcitrans by the use of molecules contained in DOM. This study therefore demonstrated, for the first time, the major modulating role of natural DOM on the toxicity of herbicides to marine microalgae

Combined Treatment with Peptide-Conjugated Phosphorodiamidate Morpholino Oligomer-PPMO and AAV-U7 Rescues the Severe DMD Phenotype in Mice

International audienceDuchenne muscular dystrophy (DMD) is a devastating neuromuscular disease caused by an absence of the dystrophin protein, which is essential for muscle fiber integrity. Among the developed therapeutic strategies for DMD, the exon-skipping approach corrects the frameshift and partially restores dystrophin expression. It could be achieved through the use of antisense sequences, such as peptide-conjugated phosphorodiamidate morpholino oligomer (PPMO) or the small nuclear RNA-U7 carried by an adeno-associated virus (AAV) vector. AAV-based gene therapy approaches have potential for use in DMD treatment but are subject to a major limitation: loss of the AAV genome, necessitating readministration of the vector, which is not currently possible, due to the immunogenicity of the capsid. The PPMO approach requires repeated administrations and results in only weak cardiac dystrophin expression. Here, we evaluated a combination of PPMO- and AAV-based therapy in a mouse model of severe DMD. Striking benefits of this combined therapy were observed in striated muscles, with marked improvements in heart and diaphragm structure and function, with unrivalled extent of survival, opening novel therapeutic perspectives for patients

Associations between prenatal PFAS exposure and preadolescents cardiometabolic health

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