Opposite regulation of human versus mouse apolipoprotein A-I by fibrates in human apolipoprotein A-I transgenic mice

The regulation of liver apolipoprotein (apo) A-I gene expression by fibrates was studied in human apo A-I transgenic mice containing a human genomic DNA fragment driving apo A-I expression in liver. Treatment with fenofibrate (0.5% wt/wt) for 7 d increased plasma human apo A-I levels up to 750% and HDL-cholesterol levels up to 200% with a shift to larger particles. The increase in human apo A-I plasma levels was time and dose dependent and was already evident after 3 d at the highest dose (0.5% wt/wt) of fenofibrate. In contrast, plasma mouse apo A-I concentration was decreased after fenofibrate in nontransgenic mice. The increase in plasma human apo A-I levels after fenofibrate treatment was associated with a 97% increase in hepatic human apo A-I mRNA, whereas mouse apo A-I mRNA levels decreased to 51%. In nontransgenic mice, a similar down-regulation of hepatic apo A-I mRNA levels was observed. Nuclear run-on experiments demonstrated that the increase in human apo A-I and the decrease in mouse apo A-I gene expression after fenofibrate occurred at the transcriptional level. Since part of the effects of fibrates are mediated through the nuclear receptor PPAR (peroxisome proliferator-activated receptor), the expression of the acyl CoA oxidase (ACO) gene was measured as a control of PPAR activation. Both in transgenic and nontransgenic mice, fenofibrate induced ACO mRNA levels up to sixfold. When transgenic mice were treated with gemfibrozil (0.5% wt/wt) plasma human apo A-I and HDL-cholesterol levels increased 32 and 73%, respectively, above control levels. The weaker effect of this compound on human apo A-I and HDL-cholesterol levels correlated with a less pronounced impact on ACO mRNA levels (a threefold increase) suggesting that the level of induction of human apo A-I gene is related to the PPAR activating potency of the fibrate used. Treatment of human primary hepatocytes with fenofibric acid (500 microM) provoked an 83 and 50% increase in apo A-I secretion and mRNA levels, respectively, supporting that a direct action of fibrates on liver human apo A-I production leads to the observed increase in plasma apo A4 and HDL-cholesterol

Introduction to the French GEOTRACES North Atlantic transect (GA01): GEOVIDE cruise

© 2018 Author(s). The GEOVIDE cruise, a collaborative project within the framework of the international GEOTRACES programme, was conducted along the French-led section in the North Atlantic Ocean (Section GA01), between 15 May and 30 June 2014. In this special issue (https://www.biogeosciences.net/special-issue900.html), results from GEOVIDE, including physical oceanography and trace element and isotope cyclings, are presented among 18 articles. Here, the scientific context, project objectives, and scientific strategy of GEOVIDE are provided, along with an overview of the main results from the articles published in the special issue

Introduction to the French GEOTRACES North Atlantic Transect (GA01): GEOVIDE cruise

The GEOVIDE cruise, a collaborative project within the framework of the international GEOTRACES programme, was conducted along the French-led section in the North Atlantic Ocean (Section GA01), between 15 May and 30 June 2014. In this special issue (https://www.biogeosciences.net/special_issue900.html), results from GEOVIDE, including physical oceanography and trace element and isotope cyclings, are presented among 18 articles. Here, the scientific context, project objectives, and scientific strategy of GEOVIDE are provided, along with an overview of the main results from the articles published in the special issue

EUREC⁴A

The science guiding the EUREC⁴A campaign and its measurements is presented. EUREC⁴A comprised roughly 5 weeks of measurements in the downstream winter trades of the North Atlantic – eastward and southeastward of Barbados. Through its ability to characterize processes operating across a wide range of scales, EUREC⁴A marked a turning point in our ability to observationally study factors influencing clouds in the trades, how they will respond to warming, and their link to other components of the earth system, such as upper-ocean processes or the life cycle of particulate matter. This characterization was made possible by thousands (2500) of sondes distributed to measure circulations on meso- (200 km) and larger (500 km) scales, roughly 400 h of flight time by four heavily instrumented research aircraft; four global-class research vessels; an advanced ground-based cloud observatory; scores of autonomous observing platforms operating in the upper ocean (nearly 10 000 profiles), lower atmosphere (continuous profiling), and along the air–sea interface; a network of water stable isotopologue measurements; targeted tasking of satellite remote sensing; and modeling with a new generation of weather and climate models. In addition to providing an outline of the novel measurements and their composition into a unified and coordinated campaign, the six distinct scientific facets that EUREC⁴A explored – from North Brazil Current rings to turbulence-induced clustering of cloud droplets and its influence on warm-rain formation – are presented along with an overview of EUREC⁴A's outreach activities, environmental impact, and guidelines for scientific practice. Track data for all platforms are standardized and accessible at https://doi.org/10.25326/165 (Stevens, 2021), and a film documenting the campaign is provided as a video supplement

EUREC⁴A

The science guiding the EUREC⁴A campaign and its measurements is presented. EUREC⁴A comprised roughly 5 weeks of measurements in the downstream winter trades of the North Atlantic – eastward and southeastward of Barbados. Through its ability to characterize processes operating across a wide range of scales, EUREC⁴A marked a turning point in our ability to observationally study factors influencing clouds in the trades, how they will respond to warming, and their link to other components of the earth system, such as upper-ocean processes or the life cycle of particulate matter. This characterization was made possible by thousands (2500) of sondes distributed to measure circulations on meso- (200 km) and larger (500 km) scales, roughly 400 h of flight time by four heavily instrumented research aircraft; four global-class research vessels; an advanced ground-based cloud observatory; scores of autonomous observing platforms operating in the upper ocean (nearly 10 000 profiles), lower atmosphere (continuous profiling), and along the air–sea interface; a network of water stable isotopologue measurements; targeted tasking of satellite remote sensing; and modeling with a new generation of weather and climate models. In addition to providing an outline of the novel measurements and their composition into a unified and coordinated campaign, the six distinct scientific facets that EUREC⁴A explored – from North Brazil Current rings to turbulence-induced clustering of cloud droplets and its influence on warm-rain formation – are presented along with an overview of EUREC⁴A's outreach activities, environmental impact, and guidelines for scientific practice. Track data for all platforms are standardized and accessible at https://doi.org/10.25326/165 (Stevens, 2021), and a film documenting the campaign is provided as a video supplement

Etude de la croissance de la truite commune Salmo trutta fario (L) dans deux rivières du Finistère

Des inventaires piscicoles réalisés depuis 1974 dans deux rivières du Finistère ont permis de préciser la croissance des populations de truites communes (Salmo trutta fario L.) par deux méthodes différentes : scalimétrie et structure de population. Les résultats font apparaître une croissance faible à modérée comparable à celle des populations de truites de certaines rivières du Pays Basque et du Massif Central ou d'Angleterre et d'Irlande du Nord. La taille moyenne à 3 ans, lors de la première ponte, est comprise entre 19 et 23,5 cm. Compte tenu de la taille légale (tolérée en Bretagne à 18 cm), la plupart des truites sont pêchées avant d'avoir pu se reproduire. L'application du modèle de RICKER à une population de truites non exploitée, en faisant varier l'effort de pêche (exploitation modérée ou forte) et la taille de première capture (15, 18 et 20 cm) montre que, dans le cas d'une exploitation modérée, l'augmentation de la taille tolérée diminuerait le nombre des prises sans augmenter le potentiel reproducteur. Si l'exploitation est forte, l'augmentation de la taille tolérée à 20 cm permet d'accroître le potentiel reproducteur tout en conservant des captures comparables en nombre et en poids à celles effectuées dans le cadre d'une exploitation modérée à partir d'une longueur totale de 18 cm. Cet exemple théorique fait apparaître la nécessité d'une connaissance approfondie des paramètres régissant la population de truites et en particulier le taux d'exploitation afin de définir une taille limite de capture appropriée

Etude de la croissance de la truite commune Salmo trutta fario (L) dans deux rivières du Finistère

Des inventaires piscicoles réalisés depuis 1974 dans deux rivières du Finistère ont permis de préciser la croissance des populations de truites communes (Salmo trutta fario L.) par deux méthodes différentes : scalimétrie et structure de population. Les résultats font apparaître une croissance faible à modérée comparable à celle des populations de truites de certaines rivières du Pays Basque et du Massif Central ou d'Angleterre et d'Irlande du Nord. La taille moyenne à 3 ans, lors de la première ponte, est comprise entre 19 et 23,5 cm. Compte tenu de la taille légale (tolérée en Bretagne à 18 cm), la plupart des truites sont pêchées avant d'avoir pu se reproduire. L'application du modèle de RICKER à une population de truites non exploitée, en faisant varier l'effort de pêche (exploitation modérée ou forte) et la taille de première capture (15, 18 et 20 cm) montre que, dans le cas d'une exploitation modérée, l'augmentation de la taille tolérée diminuerait le nombre des prises sans augmenter le potentiel reproducteur. Si l'exploitation est forte, l'augmentation de la taille tolérée à 20 cm permet d'accroître le potentiel reproducteur tout en conservant des captures comparables en nombre et en poids à celles effectuées dans le cadre d'une exploitation modérée à partir d'une longueur totale de 18 cm. Cet exemple théorique fait apparaître la nécessité d'une connaissance approfondie des paramètres régissant la population de truites et en particulier le taux d'exploitation afin de définir une taille limite de capture appropriée

Effet du procédé de friture sur la répartition et l'état de l'eau mesurée par la RMN et IRM

The effects on frying on the water distribution and the starch granules of potatoes were studied using Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI). Potatoes slices, 5 cm diameter by 1.2 cm thickness were fried for 1, 3, 6 and 9 minutes at 170° C. The NMR relaxation results allowed to monitor the structural changes after frying. Into the sample core, the starch gelatinased and included changes on the water states and distribution. At the surface, the starch crystalline structure was confirmed and the water amount decrease and oil penetration were observed. The high sample heterogeneity induced by frying was confirmed by MRI measurements.Les effets du procédé de friture sur la répartition tissulaire de l'eau et dur les granules d'amidon sont étudiés par Résonance Magnétique Nucléaire (RMN) et Imagerie de Résonance Magnétique (IRM). Des tranches de pomme de terre de 5 cm de diamètre et 1,2 cm d'épaisseur sont frites pendant 1, 3, 6 et 9 minutes à 170° C. Les relaxations RMN permettent de caractériser les changements structuraux. A coeur, l'amidon gélatinise et modifie la relaxation des molécules d'eau et leur répartition. A la surface, la structure cristalline est confirmée, la teneur en eau diminue, tandis que la teneur en huile augmente. La forte hétérogénéité induite par le traitement est validée par les images IRM

Novel constructs and vectors for the targeted and inducible expression of genes

The invention concerns novel constructs and novel vectors for the targeted and inducible expression of genes. It describes in particular novel hybrid promoters and their use for the expression of genes in hepatic cells, in vitro, ex vivo or in viv