Trace element analysis reveals bioaccumulation in the squid Gonatus fabricii from polar regions of the Atlantic Ocean

The boreoatlantic gonate squid (Gonatus fabricii) represents important prey for top predators—such as marine mammals, seabirds and fish—and is also an efficient predator of crustaceans and fish. Gonatus fabricii is the most abundant cephalopod in the northern Atlantic and Arctic Ocean but the trace element accumulation of this ecologically important species is unknown. In this study, trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, and Zn) were analysed from the mantle muscle and the digestive gland tissue of juveniles, adult females, and adult males that were captured south of Disko Island off West-Greenland. To assess the feeding habitat and trophic position of this species, stable isotopes of carbon (δ13C) and nitrogen (δ15N) were measured in their muscle tissue. Mercury concentrations were positively correlated with size (mantle length) and trophic position. The Hg/Se ratio was assessed because Se has been suggested to play a protective role against Hg toxicity and showed a molar surplus of Se relative to Hg. Cadmium concentrations in the digestive gland were negatively correlated with size and trophic position (δ15N), which suggested a dietary shift from Cd-rich crustaceans towards Cd-poor fish during ontogeny. This study provides trace element concentration data for G. fabricii from Greenlandic waters, which represents baseline data for a northern cephalopod species. Within West-Greenland waters, G. fabricii appears to be an important vector for the transfer of Cd in the Arctic pelagic food web

Ghrelin Gene Deletion Alters Pulsatile Growth Hormone Secretion in Adult Female Mice

Using preproghrelin-deficient mice (Ghrl-/-), we previously observed that preproghrelin modulates pulsatile growth hormone (GH) secretion in post-pubertal male mice. However, the role of ghrelin and its derived peptides in the regulation of growth parameters or feeding in females is unknown. We measured pulsatile GH secretion, growth, metabolic parameters and feeding behavior in adult Ghrl-/- and Ghrl+/+ male and female mice. We also assessed GH release from pituitary explants and hypothalamic growth hormonereleasing hormone (GHRH) expression and immunoreactivity. Body weight and body fat mass, linear growth, spontaneous food intake and food intake following a 48-h fast, GH pituitary contents and GH release from pituitary explants ex vivo, fasting glucose and glucose tolerance were not different among adult Ghrl-/- and Ghrl+/+ male or female mice. In vivo, pulsatile GH secretion was decreased, while approximate entropy, that quantified orderliness of secretion, was increased in adult Ghrl-/- females only, defining more irregular GH pattern. The number of neurons immunoreactive for GHRH visualized in the hypothalamic arcuate nucleus was increased in adult Ghrl-/- females, as compared to Ghrl+/+ females, whereas the expression of GHRH was not different amongst groups. Thus, these results point to sex-specific effects of preproghrelin gene deletion on pulsatile GH secretion, but not feeding, growth or metabolic parameters, in adult mice.Fil: Hassouna, Rim. Université Paris Cité; Francia. Universite de Bordeaux; Francia. Inserm; FranciaFil: Fernandez, Gimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Lebrun, Nicolas. Université Paris Cité; FranciaFil: Fiquet, Oriane. Universite de Bordeaux; Francia. Université Paris Cité; Francia. Inserm; FranciaFil: Roelfsema, Ferdinand. Leiden University Medical Center; Países BajosFil: Labarthe, Alexandra. Université Paris Cité; Francia. Universite de Bordeaux; Francia. Inserm; FranciaFil: Zizzari, Philippe. Universite de Bordeaux; Francia. Université Paris Cité; Francia. Inserm; FranciaFil: Tomasetto, Catherine. Universite de Bordeaux; Francia. Université Paris Cité; Francia. Inserm; FranciaFil: Epelbaum, Jacques. Universite de Bordeaux; Francia. Université Paris Cité; Francia. Inserm; FranciaFil: Viltart, Odile. Universite de Bordeaux; Francia. Université Paris Cité; Francia. Inserm; FranciaFil: Chauveau, Christophe. Université Du Littoral Côte D‘opale; FranciaFil: Perello, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Tolle, Virginie. Université Paris Cité; Franci

Factor Viral: Proyecto de Comunicación para el Desarrollo para promover buenas prácticas profesionales en torno al racismo en estudiantes de comunicaciones de Lima

La presente investigación plantea el diagnóstico, diseño y aplicación de actividades piloto del Proyecto de Comunicación “Factor Viral”. Esto se llevó a cabo como parte del curso Proyecto de Comunicación para el Desarrollo. En ella se aborda la problemática del racismo en las comunicaciones, y en específico en estudiantes de comunicaciones, desde cuatro aspectos comunicacionales fundamentales: la identificación y cuestionamiento de lo que se considera normal en cuanto a las jerarquías de estatus en el imaginario limeño, el reconocimiento del racismo, junto con actitudes y prácticas, como un problema estructural normalizado, la interpelación personal sobre el tema, junto con la discusión de este mismo con sus pares, la cocreación de lineamientos orientados a mitigar prácticas racistas en los medios de comunicación y la incidencia en espacios físicos y/o virtuales en referencia a esta problemática. Se decidió trabajar con jóvenes estudiantes de la carrera de comunicaciones de diversas universidades y/o institutos que actualmente estén cursando entre octavo a décimo ciclo. El trabajo de investigación se ha enfocado en cuatro fases de cambio de los estudiantes de comunicaciones, esto aplicado desde cuatro estrategias comunicacionales, basadas en una metodología lúdicoparticipativa, de eduentretenimiento y creación-acción, resaltando la aplicación de metodologías ágiles en un contexto virtual, debido al distanciamiento físico obligatorio a raíz del virus Covid-19. Esta propuesta puede tener replicabilidad en cada una de las casas de estudio de los futuros comunicadores y comunicadoras para que estos puedan adoptar un enfoque crítico en torno al racismo y otros temas que siguen aquejando al país. Por lo tanto, el proyecto permite tener una mirada empática en torno al tema y, a través del aprendizaje colectivo, se incentiva a los y las jóvenes estudiantes a poder ser agentes de cambio, no solo desde la esfera personal sino también profesiona

Overexpression of Wild-Type Human Alpha-Synuclein Causes Metabolism Abnormalities in Thy1-aSYN Transgenic Mice

Parkinson’s disease is a progressive neurodegenerative disorder characterized by loss of dopaminergic neurons, pathological accumulation of alpha-synuclein and motor symptoms, but also by non-motor symptoms. Metabolic abnormalities including body weight loss have been reported in patients and could precede by several years the emergence of classical motor manifestations. However, our understanding of the pathophysiological mechanisms underlying body weight loss in PD is limited. The present study investigated the links between alpha-synuclein accumulation and energy metabolism in transgenic mice overexpressing Human wild-type (WT) alpha-synuclein under the Thy1 promoter (Thy1-aSYN mice). Results showed that Thy1-aSYN mice gained less body weight throughout life than WT mice, with significant difference observed from 3 months of age. Body composition analysis of 6-month-old transgenic animals showed that body mass loss was due to lower adiposity. Thy1-aSYN mice displayed lower food consumption, increased spontaneous activity, as well as a reduced energy expenditure compared to control mice. While no significant change in glucose or insulin responses were observed, Thy1-aSYN mice had significantly lower plasmatic levels of insulin and leptin than control animals. Moreover, the pathological accumulation of alpha-synuclein in the hypothalamus of 6-month-old Thy1-aSYN mice was associated with a down-regulation of the phosphorylated active form of the signal transducer and activator of transcription 3 (STAT3) and of Rictor (the mTORC2 signaling pathway), known to couple hormonal signals with the maintenance of metabolic and energy homeostasis. Collectively, our results suggest that (i) metabolic alterations are an important phenotype of alpha-synuclein overexpression in mice and that (ii) impaired STAT3 activation and mTORC2 levels in the hypothalamus may underlie the disruption of feeding regulation and energy metabolism in Thy1-aSYN mice

Culture et numérique. Rencontre franco-québécoise

International audienceLa culture a toujours entretenu des rapports étroits avec la technique. A ce titre, le numérique a une influence certaine tant dans la définition des objets culturels (jeux vidéo, créations générées par une intelligence artificielle...) que dans leur diffusion, impliquant même parfois la mise en place de nouveaux équilibres. Cet ouvrage constitue les actes du colloque annuel du Master 2/LLM Propriété intellectuelle fondamentale et technologies numériques (Université Paris-Sud/Paris-Saclay et Université Laval) et offre ainsi une lecture franco-québécoise des enjeux liés à la culture (au sens large) dans l’environnement numérique

La ghréline : une hormone gastrique impliquée dans la régulation de la croissance et de l’appétit

La ghréline est une hormone peptidique acylée de 28 acides aminés issue du tractus gastro-intestinal. Elle a initialement été identifiée comme le ligand endogène du GHS-R1a (Growth Hormone Secretagogue Receptor 1a) et pour son puissant effet sécrétagogue de l’hormone de croissance (GH). La ghréline est également un facteur orexigène et adipogène qui participe à la régulation à long terme de l’homéostasie énergétique. Ainsi, cette hormone apparaît comme un facteur clé dans la régulation de fonctions essentielles à la vie au carrefour entre nutrition, métabolisme et croissance. Toutefois, le rôle du système ghréline/GHS-R dans la physiologie de la croissance, du comportement alimentaire et du métabolisme reste mal compris. L’utilisation complémentaire d’outils pharmacologiques ou de modèles animaux déficients pour le gène de la préproghréline, de l’enzyme d’acylation de la ghréline (Ghrelin-O-acyl-transferase, GOAT) ou du GHS-R dans des situations de dénutrition chronique ou de régime riche en graisses permet aujourd’hui de mieux appréhender le rôle de la ghréline dans la physiopathologie des troubles alimentaires et métaboliques

Gottfried Benn (poésie et philosophie)

Gottfried Benn est connu pour son oeuvre poétique. Il est pourtant aussi nouvelliste et essayiste : c'est dans ses essais qu'il élabore une poétique du faire, une poïétique. Les questions qu'il pose sont d'ordre philosophique. Pourquoi ? Parce que Benn considère que l'art permet de dépasser la fin de la métaphysique. Benn affirme que l'art, la création sont une manière de surmonter le nihilisme. Puisque le nihilisme a détruit tous les contenus, il reste la forme. "Les formes"..., c'est là l'important, voilà le fin mot de sa morale. Ce qu'elles sont reste à décider mais sûrement quelque chose de très élémentaire : rythme, tension, "processus,..." (Double vie, p.160). Gottfried Benn veut créer une poétique de la forme. Une poétique doit pour lui tenir compte de cette réalité élémentaire et essentielle à la fois ; la création est un processus, l'oeuvre d'art est un faire. C'est une poïétique, faite de tensions, de rythmes, qui expriment le moi lyrique...STRASBOURG-B.N.U.S. (674821001) / SudocSudocFranceF

Trophic ecology drives trace element concentrations in the Antarctic octopod community

Highlights: • Stable isotope values vary among species with Adelieledone polymorpha, having highest values. • Variations in trace element concentrations suggest different feeding ecology. • Antarctic incirrate octopods are likely vectors of As, Cd and Hg to their predators. • Sex influences Cd, Co, Cu, Fe, Pb and Zn concentrations. Despite the Antarctic Ocean being considered a pristine environment, elevated trace element concentrations have been reported in many marine organisms. The Antarctic Ocean is particularly vulnerable to climate change, which can also affect the bioaccumulation of trace element concentrations in biota. While Antarctic octopods are key components of the regional food webs as prey for a variety of predators (e.g., seals, fish, and seabirds), their contamination state by trace elements remains largely unknown. This study investigated the trace element concentrations in relation to the trophic ecology in Antarctic octopods. Stable isotope values (δ13C and δ15N) and trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V, and Zn) were measured in eight different species (Adelieledone polymorpha, Pareledone aequipapillae, P. albimaculata, P. aurata, P. charcoti, P. cornuta, P. felix, and P. turqueti) sampled near Elephant Island, close to the Antarctic Peninsula. Stable isotopes of δ15N varied among species, with significant differences between A. polymorpha and P. aurata suggesting potential niche segregation. Trace element concentrations also differed among species and with sampling depth, which likely reflects their trophic ecology. The data presented in this study provides the first insight into the trace element concentrations for these endemic octopods in this vulnerable habitat and their stable isotope value

Influence of sexual dimorphism on stable isotopes and trace element concentrations in the greater hooked squid Moroteuthopsis ingens from New Zealand waters

International audienceThe Chatham Rise, one of the highest offshore-primary production regions in New Zealand waters, hosts a great abundance and diversity of deep-sea cephalopods including the greater hooked squid, Moroteuthopsis ingens. Stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) and trace element concentrations (Ag, As, Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb, Se, V, and Zn) were assessed in female and male specimens of different size classes (89–563 mm mantle length). Values of δ13C and δ15N were overall higher in females and δ13C was further influenced by size and sex. Both muscular mantle (the largest fraction of the total body mass) and digestive gland (the known main storage organ for Ag, Cd, Cu and Zn in many cephalopods) tissues were analysed. Higher levels of Cd were observed in males than in females. A positive effect was found between size and Hg concentrations, which could be related to the ontogenetic descent of larger specimens into deeper waters, where they are exposed to higher Hg concentrations, and/or dietary shifts toward Hg-enriched prey with increasing size. This study provides trace element data for this abundant and ecologically important species, and further reveals higher trace element concentrations (especially Hg) in M. ingens from the Chatham Rise, compared to specimens from the sub-Antarctic zone