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Développement pubertaire des mâles entiers et risque d’odeur de verrat
No full textLa castration des porcelets mâles a pour but de diminuer les risques de comportement agressif et d’éviter des défauts de qualité de viande. En effet, chez certains mâles entiers, l’androsténone (molécule produite dans les testicules) et le scatol (produit par les bactéries du tube digestif) s’accumulent dans le gras et donnent une odeur désagréable à la viande. Dans une perspective d’élevage de mâles entiers, une sélection contre l’accumulation d’androsténone dans le gras est envisagée, mais les éventuels effets négatifs sur la reproduction restent à analyser. L’objectif de l’étude est d’évaluer les relations entre l’accumulation d’androsténone dans le gras dorsal, la mise en place de la puberté chez les jeunes verrats, le comportement sexuel et les caractéristiques de la semence chez les verrats matures. Un phénotypage fin a été réalisé sur 114 verrats dans l’unité expérimentale INRA GenESI. Chaque verrat totalise jusqu’à 455 observations comprenant des mesures de production spermatique, des dosages d’androsténone et de scatol dans le gras dorsal et d’hormones plasmatiques (testostérone et œstradiol) à 180 jours et à 280 jours d’âge, des observations du comportement (débourrage, maintien de l’aptitude au prélèvement de semence et test de confiance vis-à-vis de l’homme) et des caractéristiques de semence. Des analyses multivariées ont été effectuées pour estimer les relations entre ces mesures. Les résultats suggèrent que l’œstradiol plasmatique peut servir de prédicteur de l’androsténone et qu’il n’y a pas de lien entre l’androsténone, les caractéristiques de la semence et le comportement sexuel des verrats.Male piglets are castrated to reduce the risk of aggressive behavior and improve meat quality. In some entire males, androstenone (from testes) and skatole (produced by the gut bacteria) accumulate in fat and give an unpleasant smell to the meat. Genetic selection against androstenone accumulation in back fat in entire males has been considered to overcome boar taint in carcasses, but possible side effects on reproductive traits have to be investigated. The objective of the study was to evaluate the relationship between androstenone accumulation in back fat, beginning of puberty, sexual behavior and semen characteristics in mature boars.To meet this objective, fine phenotyping of 114 boars was performed at the INRA GenESI experimental station. Each boar represented up to 455 observations, tests or samples, including concentrationsof androstenone and skatole in back fat, concentrations of hormones in blood at 180 and 280 days of age, behavioral observations (breaking, maintaining libido and test of confidence in humans) and semen characteristics. Multivariate analysis was performed to estimate the relationships between variables. Results suggest that plasma œstradiol may predict androstenone and that there was no relationship between androstenone, semen characteristics, and boar libid
Complementarity of empirical and process-based approaches to modelling mosquito population dynamics with Aedes albopictus as an example—Application to the development of an operational mapping tool of vector populations
No full textMosquitoes are responsible for the transmission of major pathogens worldwide. Modelling their population dynamics and mapping their distribution can contribute effectively to disease surveillance and control systems. Two main approaches are classically used to understand and predict mosquito abundance in space and time, namely empirical (or statistical) and process-based models. In this work, we used both approaches to model the population dynamics in Reunion Island of the 'Tiger mosquito', Aedes albopictus, a vector of dengue and chikungunya viruses, using rainfall and temperature data. We aimed to i) evaluate and compare the two types of models, and ii) develop an operational tool that could be used by public health authorities and vector control services. Our results showed that Ae. albopictus dynamics in Reunion Island are driven by both rainfall and temperature with a non-linear relationship. The predictions of the two approaches were consistent with the observed abundances of Ae. albopictus aquatic stages. An operational tool with a user-friendly interface was developed, allowing the creation of maps of Ae. albopictus densities over the whole territory using meteorological data collected from a network of weather stations. It is now routinely used by the services in charge of vector control in Reunion Island
Design, synthesis, and antiprotozoal evaluation of new 2,4-bis[(substituted-aminomethyl)phenyl]quinoline, 1,3-bis[(substituted-aminomethyl)phenyl]isoquinoline and 2,4-bis[(substituted-aminomethyl)phenyl]quinazoline derivatives.
No full textA series of new 2,4-bis[(substituted-aminomethyl)phenyl]quinoline, 1,3-bis[(substituted-aminomethyl)phenyl]isoquinoline, and 2,4-bis[(substituted-aminomethyl)phenyl]quinazoline derivatives was designed, synthesised, and evaluated in vitro against three protozoan parasites (Plasmodium falciparum, Leishmania donovani, and Trypanosoma brucei brucei). Biological results showed antiprotozoal activity with IC50 values in the µM range. In addition, the in vitro cytotoxicity of these original molecules was assessed with human HepG2 cells. The quinoline 1c was identified as the most potent antimalarial candidate with a ratio of cytotoxic to antiparasitic activities of 97 against the P. falciparum CQ-sensitive strain 3D7. The quinazoline 3h was also identified as the most potent trypanosomal candidate with a selectivity index (SI) of 43 on T. brucei brucei strain. Moreover, as the telomeres of the parasites P. falciparum and Trypanosoma are possible targets of this kind of nitrogen heterocyclic compounds, we have also investigated stabilisation of the Plasmodium and Trypanosoma telomeric G-quadruplexes by our best compounds through FRET melting assays
Roles of SlETR7, a newly discovered ethylene receptor, in tomato plant and fruit development
No full textEthylene regulates many aspects of plant growth and development. It is perceived by a family of ethylene receptors(ETRs) that have been well described. However, a full understanding of ETR function is complicated by functionalredundancy between the receptor isoforms. Here, we characterize a new ETR, SlETR7, that was revealed by tomatogenome sequencing.SlETR7expression in tomato fruit pericarp increases when the fruit ripens and its expression issynchronized with the expression ofSlETR1,SlETR2, andSlETR5which occurs later in the ripening phase than theincrease observed forSlETR3,SlETR4, andSlETR6. We uncovered an error in theSlETR7sequence as documented in theITAG 3 versions of the tomato genome which has now been corrected in ITAG 4, and we showed that it belongs tosub-family II. We also showed that SlETR7 specifically binds ethylene. Overexpression (OE) ofSlETR7resulted in earlierflowering, shorter plants, and smaller fruit than wild type. Knock-out (KO) mutants ofSlETR7produced more ethyleneat breaker (Br) and Br+2 days stages compared to wild type (WT), but there were no other obvious changes in theplant and fruit in these mutant lines. We observed that expression of the otherSlETRsis upregulated in fruit ofSlETR7KO mutants, which may explain the absence of obvious ripening phenotypes. Globally, these results show that SlETR7is a functional ethylene receptor. More work is needed to better understand its specific roles related to the six othertomato ETR
Combination of PI3K and MEK inhibitors yields durable remission in PDX models of PIK3CA-mutated metaplastic breast cancers
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Success factors of innovations
No full textThe French seafood sector is currently confronted with increasing competition from imported products, price fluctuations and new challenges such as environmental issues. In the face of these issues, producers may not be able to meet consumer expectations, and new products intended to boost growth in the seafood sector may not succeed. To clarify the drivers of competitiveness in the seafood sector, a greater understanding of the success factors behind seafood innovation is needed. We use an original database obtained from the merger of two databases. We combine Mintel’s Global New Products Database, which identifies new products launched in France in 2010, 2011 and 2012, with consumption data spanning 2010 to 2014 from a household panel (Kantar). The data allow us to track the quantities of 246 new products purchased in the year after their launch. We run an ordered logit model to measure the impact of product, marketing and market variables on the probability of a product becoming successful. We identify three possibilities: success, i.e., the product is still on the market one year after its launch with an increased quantity; stagnation, i.e., the product is still on the market one year after its launch with a decreased quantity; and failure, i.e., the product is no longer on the market at all a year after its launch. We also run a Cox proportional hazards model with the products’ time on the market as the dependent variable. The model estimates the time that elapses before the product disappears. The results show that three kinds of factors influence competitiveness: firm characteristics (size, specialization), market economic situation and, to a lesser extent, the marketing process.Le secteur français des produits de la pêche et de l’aquaculture est confronté à une concurrence croissante des produits importés, aux fluctuations de prix et à de nouveaux défis tels que les enjeux environnementaux. Face à ces problèmes, les producteurs pourraient ne pas être en mesure de répondre aux attentes des consommateurs et les nouveaux produits destinés à stimuler la croissance pourraient ne pas réussir à trouver leur place sur ce marché. Pour mettre en avant les leviers de la compétitivité, une meilleure compréhension des facteurs de réussite de l'innovation est nécessaire. Nous utilisons une base de données originale issue de la fusion de deux bases de données. Nous combinons la base de données mondiale des nouveaux produits de Mintel, qui identifie les nouveaux produits lancés en France en 2010, 2011 et 2012, avec des données de consommation couvrant la période 2010 à 2014 à partir d'un panel de ménages (Kantar). Les données nous permettent de suivre les quantités de 246 nouveaux produits achetés dans l'année suivant leur lancement. Nous utilisons un modèle Logit ordonné pour mesurer l'impact des variables de produit, de marketing et de marché sur la probabilité de réussite d'un produit. Nous identifions trois possibilités : succès, stagnation et échec. Pour compléter ce modèle, nous utilisons également un modèle de risques proportionnels de Cox avec la durée des produits sur le marché comme variable dépendante. Les résultats montrent que trois types de facteurs influencent la compétitivité : les caractéristiques des entreprises, la situation économique du marché et, dans une moindre mesure, les variables marketing
