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High-resolution seismic reflection data have been used over the last decades to estimate the thickness of the long-term Blue Carbon sink associated to the below-ground sediment deposit (matte) of the Posidonia oceanica meadows. Time-to-depth conversion of these geophysical datasets was usually performed assuming a sound velocity in this structure, but appropriate seismic interval velocity measurements is necessary to achieve accurate calibration. This study describes the first methodology to estimate the seismic interval velocity in the matte. This approach performed on the eastern continental shelf of Corsica island (France, NW Mediterranean) is based on measurements of the vertical matte profile from high-resolution seismic reflection profiles (s TWTT) and from seafloor morpho-bathymetric DTM (multibeam echosounders - MBES and Light Detection and Ranging - LiDAR surveys) calibrated with ground-truthing data. A biogeosedimentological analysis of horizontal cores sampled in vertical matte escarpments has been undertaken to identify the potential relationship of sediment and environmental parameters with sound velocity. The cross-comparison and the data intercalibration show significant correlation of MBES (R2 = 0.872) and LiDAR datasets (R2 = 0.883) with direct underwater measurements. Seismic interval velocities (n = 367) have been found to range between 1631.9 and 1696.8 m s−1 (95% confidence interval) and are estimated on average at 1664.4 m s−1, which is similar to the literature for unconsolidated marine sediments. The prediction map provided by the ordinary kriging method emphasized, however, a high variability of sound velocity within the study area. The results showed that changes in sound velocity in the matte are positively and strongly correlated with sand and gravel content and environmental factors such as distance to coastal river mouths and coastline. However, it was found that a negative relationship linked sound velocity with total and coarse organic content of matte deposits.

In this study, Hapke's radiative transfer model is used to verify the feasibility of retrieving the composition and grain-size of the ground in an open-pit mine, seen as a regolith. Such a tool could be useful for dust surveys and thus preventing potential environmental risks such as acid mine drainage. As the true compositional endmembers of the medium are not retrieved but rather chosen from spectral libraries and the range of grain sizes (a few to hundreds of micrometers) and porosities (0.22 to 0.52 for the filling factor) vary greatly in an open-pit mine, we show that the mineralogical unmixing results are not reliable. Too many combinations of different relative abundances, grain sizes and porosities lead to fits between modelled and measured spectra under 0.3% in reflectance. To tackle this issue, we explore a lithological unmixing approach. Considering lithologies as endmembers, as opposed to considering minerals, reduces the variability in the solutions as fewer endmembers are used. The results show that the studied samples with multi-component grains behave spectrally as expected for mono-mineral grains. With no root mean square errors higher than 5%, the relative abundances retrieved are sufficiently precise to consider mapping lithologies with this method.

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One challenging point in analyzing cellular secretome collected as conditioned medium is cross-contamination by cell culture media components, especially bovine serum proteins. A common approach for serum removal is to wash the cells, an alternative is to grow cells using serum-free conditions. Given that the sample processing may influence the phenotype of cells and thus the secretome, it is important to establish the optimal protocol for each cell type. In this study, we compared two methods for preparing conditioned medium from human adipocytes derived from mesenchymal stem cells. Cells were either washed twice with PBS or cultured the last four days of differentiation in serum-free adipogenic medium. Gene expression of the cells was evaluated by using real-time PCR and 1D LC-MS/MS was used to compare secreted proteins present in the culture supernatants. Surprisingly, results showed significant differences in gene expression patterns of the cells and in protein content of the conditioned media and suggested that PBS washes induced severe modifications of the phenotype of cells and thus changes in protein secretion profiles. These data emphasize the significant variations in protein species related to cell manipulations and underline the importance of procedure optimization prior to any proteomic investigation.

International audience; Model checking has made a lot of progress since its infancy. For a long time, industrial applications were still limited to some very specific domains out of which the technique bumps into the state explosion wall. Nowadays things evolve and some tools are able to tackle real world use cases outside of the known domains. We give here the feedback collected when using model checking on several industrial strength use cases and give indication on how we take into account the specific domain constraints. 1 Model Checking for Industrial Problems Model checking refers to the problem of exhaustively and automatically checking whether a given model of a system meets a given specification. Model Checking is now an old technique which takes its ground in the mid 1970s as a response to concurrent problem analysis. It was until recently essentially confined to some specific areas, such as hardware analysis or protocol verification. Extension to other domains such as software verification has always been difficult due to the combinatorial explosion problem (the size of the space state grows exponentially with the size of the problem to analyze). However, recent developments in a variety of fields, ranging from symbolic model checking to SAT solver engines and including model checker parallelization lead to a broader range of application in industry including software analysis.

Guidelines recommend wound care and/or local therapy as first-line treatment for cutaneous leishmaniasis. An analysis of a referral treatment program in 135 travelers showed that this approach was feasible in 62% of patients, with positive outcome in 83% of evaluable patients

Dans le cadre de la surveillance du milieu marin du site électronucléaire de PENLY (Seine-Maritime), le domaine benthique côtier de Dieppe à Criel-sur-mer a fait l’objet d’une prospection biomorphosédimentaire en avril et mai 2014, comme celles réalisées en 1988, 1992, 1996, 2000, 2008 et 2004.

12 páginas, 3 figuras, This synopsis focuses on the effects of climate change on Mediterranean seagrasses, and associated communities, and on the contribution of the main species, Posidonia oceanica, to the mitigation of climate change effects through sequestering carbon dioxide. Whilst the regression of seagrass meadows is well documented, generally linked to anthropogenic pressures, global warming could be a cause of new significant regression, notably linked to the introduction of exotic species, the rise of Sea-Surface Temperature (SST), and relative sea level. Seagrass communities could also be affected by climate change through the replacement of high structural complexity seagrass species by species of lower complexity and even by opportunistic introduced species. Although it is currently very difficult to predict the consequences of these alterations and their cascade effects, two main potential conflicting trends in the functioning of seagrass ecosystems are acceleration of the herbivore pathway or the detritivore pathway. The mean net primary production of the dominant species, Posidonia oceanica, is relatively high and can be estimated to range between 92.5 to 144.7 g C m-2 a-1. Around 27% of the total carbon fixed by this species enters the sedimentary pathway leading to formation, over millennia, of highly organic deposits, rich in refractory carbon. At the Mediterranean scale, the sequestration rate might reach 1.09 Tg C a-1. The amount of this stored carbon is estimated to range from 71 to 273 kg C m-2, which when considered at the Mediterranean scale would represent 11 to 42% of the CO2 emissions produced by Mediterranean countries since the beginning of the Industrial Revolution. The greatest value of the P. oceanica ecosystem, in the context of mitigation of global climate change, is linked to this vast long-term carbon stock accumulated over millennia, and therefore, efforts should be focused on preserving the meadows to keep this reservoir intact., The authors would like to thank IUCN-Med for financial support.

International audience; Background: In osteoporosis, bone loss is accompanied by increased marrow adiposity. Given their proximity in the bone marrow and their shared origin, a dialogue between adipocytes and osteoblasts could be a factor in the competition between human Mesenchymal Stem Cells (hMSC) differentiation routes, leading to adipocyte differentiation at the expense of osteoblast differentiation. The adipocyte/osteoblast balance is highly regulated at the level of gene transcription. In our work, we focused on PPARgamma, CEBPalpha and CEBPdelta, as these transcription factors are seen as master regulators of adipogenesis and expressed precociously, and on leptin and adiponectin, considered as adipocyte marker genes. In 2010, our group has demonstrated, thanks to a coculture model, that in the presence of hMSC-derived adipocytes (hMSC-Adi), hMSC-derived osteoblasts (hMSC-Ost) express lesser amounts of osteogenic markers but exhibit the expression of typical adipogenic genes. Nevertheless, the mechanisms underlying this modulation of gene expression are not clarified. Recently, adipocytes were described as releasing extracellular vesicles (EVs), containing and transferring adipocyte specific transcripts, like PPARgamma, leptin and adiponectin. Here, we investigated whether EVs could be the way in which adipocytes transfer adipogenic RNAs in our coculture model.Results: We observed in hMSC-Ost incubated in hAdi-CM an increase in the adipogenic PPARγ, leptin, CEBPα and CEBPδ transcripts as well as the anti-osteoblastic miR-138, miR30c, miR125a, miR-125b, miR-31 miRNAs, probably implicated in the observed osteocalcin (OC) and osteopontin (OP) expression decrease. Moreover, EVs were isolated from conditioned media collected from cultures of hMSC at different stages of adipocyte differentiation and these specific adipogenic transcripts were detected inside. Finally, thanks to interspecies conditioned media exposition, we could highlight for the first time a horizontal transfer of adipogenic transcripts from medullary adipocytes to osteoblasts.Conclusions: Here, we have shown, for the first time, RNA transfer between hMSC-derived adipocytes and osteoblasts through EVs. Additional studies are needed to clarify if this mechanism has a role in the adipocytic switch driven on osteoblasts by adipocytes inside bone marrow and if EVs could be a target component to regulate the competition between osteoblasts and adipocytes in the prevention or in the therapy of osteoporosis and other osteopenia.

A consensus genetic map for chicory (2n = 2x = 18) was obtained after the integration of molecular marker data of two industrial chicory progenies (K28K59, Rubis118) and one witloof chicory progeny (BR). As a limited number of co-dominant markers was available at the beginning of this work, three different microsatellite-enriched libraries were produced from genomic DNA, resulting in 420, 719 and 1,251 sequences, respectively. The level of informative Simple Sequence Repeat (SSR) sequences from the three libraries ranged from 28 to 40%, thus defining a set of 730 SSR markers available for polymorphism screening. A subset of 81 Sequence-Tagged Sites (STS) developed from EST, cDNA, genes, and non-coding sequences was screened through Single Strand Conformational Polymorphism (SSCP) analysis, leading to 46 polymorphic loci integrated in the genetic maps. Markers were grouped and ordered on 9 homologous Linkage Groups (LG) for each of the three maps: 274 markers in K28K59, 282 markers in Rubis118, 178 markers in BR. Co-linear regions between maps were identified through 193 ‘bridge’ markers that allowed the integration of the 9 homologous LG in a consensus map containing 472 markers and covering 878 cM. Comparison across maps revealed the presence of 4 conserved regions with significant distorted markers, also defined as Segregation Distortion Regions (SDR), affected by gametic or zygotic selection factors. Marker distribution was not always uniform; 6 LG possessed homologous clustered regions in all maps. The consensus map could be the starting point for the identification and the cloning of major genes and QTL in fundamental and applied genetic areas in chicory.

The cichlids of East Africa are renowned as one of the most spectacular examples of adaptive radiation. They provide a unique opportunity to investigate the relationships between ecology, morphological diversity, and phylogeny in producing such remarkable diversity. Nevertheless, the parameters of the adaptive radiations of these fish have not been satisfactorily quantified yet. Lake Tanganyika possesses all of the major lineages of East African cichlid fish, so by using geometric morphometrics and comparative analyses of ecology and morphology, in an explicitly phylogenetic context, we quantify the role of ecology in driving adaptive speciation. We used geometric morphometric methods to describe the body shape of over 1000 specimens of East African cichlid fish, with a focus on the Lake Tanganyika species assemblage, which is composed of more than 200 endemic species. The main differences in shape concern the length of the whole body and the relative sizes of the head and caudal peduncle. We investigated the influence of phylogeny on similarity of shape using both distance-based and variance partitioning methods, finding that phylogenetic inertia exerts little influence on overall body shape. Therefore, we quantified the relative effect of major ecological traits on shape using phylogenetic generalized least squares and disparity analyses. These analyses conclude that body shape is most strongly predicted by feeding preferences (i.e., trophic niches) and the water depths at which species occur. Furthermore, the morphological disparity within tribes indicates that even though the morphological diversification associated with explosive speciation has happened in only a few tribes of the Tanganyikan assemblage, the potential to evolve diverse morphologies exists in all tribes. Quantitative data support the existence of extensive parallelism in several independent adaptive radiations in Lake Tanganyika. Notably, Tanganyikan mouthbrooders belonging to the C-lineage and the substrate spawning Lamprologini have evolved a multitude of different shapes from elongated and Lamprologus-like hypothetical ancestors. Together, these data demonstrate strong support for the adaptive character of East African cichlid radiations.

International audience; One challenging point in analyzing cellular secretome collected as conditioned medium is cross-contamination by cell culture media components, especially bovine serum proteins. A common approach for serum removal is to wash the cells, an alternative is to grow cells using serum-free conditions. Given that the sample processing may influence the phenotype of cells and thus the secretome, it is important to establish the optimal protocol for each cell type. In this study, we compared two methods for preparing conditioned medium from human adipocytes derived from mesenchymal stem cells. Cells were either washed twice with PBS or cultured the last four days of differentiation in serum-free adipogenic medium. Gene expression of the cells was evaluated by using real-time PCR and 1D LC-MS/MS was used to compare secreted proteins present in the culture supernatants. Surprisingly, results showed significant differences in gene expression patterns of the cells and in protein content of the conditioned media and suggested that PBS washes induced severe modifications of the phenotype of cells and thus changes in protein secretion profiles. These data emphasize the significant variations in protein species related to cell manipulations and underline the importance of procedure optimization prior to any proteomic investigation.

The coastal vegetation, and in particular the seagrasses, plays a major role in the fixation of carbon. Posidonia oceanica, a species endemic to the Mediterranean, is of particular interest because of the constitution of a particular structure, the matte, which enables the sequestration of carbon over long periods of time. An initial assessment of the stocks of carbon sequestrated within the matte has been undertaken in two sectors of the NATURA 2000 site “Grand Herbier de la Plaine Orientale”, Biguglia in the north and Aléria in the south. The surface area of the meadow has been measured by means of the combined use of aerial remote sensing (shallow zone) and side-scan sonar (deep zone). The thickness of the matte has been assessed by means of seismic reflection using a 2.5 KHz sediment probe and a sparker. The calibration of the seismic data was performed by scuba diving at the level of intermatte cliffs, clearly visible on the seismic profiles. The seagrass meadow at the NATURA 2000 site extends from 3 to 41 m depth and covers an estimated total area of 22 667 ha, or 52.4% of the bottom between 0 and 50 m depth. The speed of propagation within the matte (celerity), estimated by comparison of the field data (intermatte) and the seismic profiles, ranges from 1 600 to 1 700 m.s-1. The thickness of the matte, estimated on the basis of the mean celerity, is on average 2.7 m for the Biguglia zone where it may locally exceed 8 m; it is on average 3.2 m for the Aléria zone where it may exceed 13 m, in particular off the mouth of the coastal river Tavignano. The presence of matte beneath the sediment should also be noted in patches of sand within the meadow and also beyond the lower limit. The quantity of carbon sequestered at this NATURA 2000 site may exceed 60 million tons. However, it would be necessary to carry out coring within the matte, in several representative sectors, in order to assess more accurately the amounts of carbon sequestered at this site.

One challenging point in analyzing cellular secretome collected as conditioned medium is cross-contamination by cell culture media components, especially bovine serum proteins. A common approach for serum removal is to wash the cells, an alternative is to grow cells using serum-free conditions. Given that the sample processing may influence the phenotype of cells and thus the secretome, it is important to establish the optimal protocol for each cell type. In this study, we compared two methods for preparing conditioned medium from human adipocytes derived from mesenchymal stem cells. Cells were either washed twice with PBS or cultured the last four days of differentiation in serum-free adipogenic medium. Gene expression of the cells was evaluated by using real-time PCR and 1D LC-MS/MS was used to compare secreted proteins present in the culture supernatants. Surprisingly, results showed significant differences in gene expression patterns of the cells and in protein content of the conditioned media and suggested that PBS washes induced severe modifications of the phenotype of cells and thus changes in protein secretion profiles. These data emphasize the significant variations in protein species related to cell manipulations and underline the importance of procedure optimization prior to any proteomic investigation.

The regression of seagrass meadows has been extensively studied over the past few years. Although the causes of this regression may be locally natural, it is more generally related to human impact. In the framework of the HalGolo (2010) and CoralCorse (2013) oceanographic campaigns, acoustic data (mosaic of sonograms and bathymetry), validated by field data (Scuba diving, ROV), were acquired at depths of -10 m and -50 m at the NATURA 2000 site “Grand Herbier de la Plaine Orientale” (Western Mediterranean, Corsica). Processing of this data provided evidence of the scale of this mechanical degradation (trawling scars, mooring, etc.), and enabled its quantification with regard to surface area and scar density. The main degradation was observed between -20 and – 40 m depth (98%); the surface area of seagrass meadow destroyed is estimated at 280 ha with more than 40 scars per hectare recorded in the northern part of the site. Given the slow growth rate of the meadow, assuming the hypothesis of the ending of these practices, it would require almost 150 years to recover these scars.

A new coralligenous morphotype named ‘atolls’ was discovered in 2011 in northern Cap Corse (Western Mediterranean Sea). With the aim of inventorying and characterizing these structures, and to attempt to shed light on their origins, two oceanographic campaigns (using e.g. side scan sonar, multibeam echosounder, sparker, ROV and submarine with 3D photogrammetry) were carried out in 2013 and 2014, in this sector, and in the south of the island in search of similar structures. Off Cap Corse, nearly one thousand atolls were identified between 105 and 130 m depth; the majority of them are situated between 110 and 125 m depth. These atolls are generally grouped (several tens to several hundred) and are to be found in two main sectors, situated between 22 and 31 km from the coast. They occur on subhorizontal bottoms, in rocky depressions occupied by coastal detritic bottom, and are 1 to 2 m thick. The average size of these atolls ranges from 20 to 25 m in diameter, but a few smaller or more extensive structures have been identified. The height of the central core ranges from 0.5 to 3.0 m, the intermediate zone, which surrounds this core, presents a width of about 10 m, and the exterior crown has a width of 1 to 5 m. No atoll was found along the south coast although the topography is similar (bathymetric patterns, presence of a seamount). Several typologies have been evidenced; these typologies could correspond to atolls at different stages of evolution in relation to phenomena of bioerosion or bioconstruction. Furthermore, the occurrence of ‘fossil coralligenous’ formations, between 138 and 140 m depth, with still living rhodoliths at the summit, might support the hypothesis of a biological origin, with the original formation occurring during a period when the sea level was lower, several thousand years ago.

Quatre leves morpho-sedimentaires, obtenus au moyen du sonar a balayage lateral, ont ete realises sur le domaine marin cotier Dieppe/Le Treport (Seine Maritime), entre 1988 et 2000. Les resultats sont integres dans une base d’information geographique qui permet d’observer les changements dans la repartition des facies sedimentaires. Cette analyse montre un ensablement notable des fonds graveleux a l’est de Penly. L’ensablement concomitant de certains estrans rocheux, alors que les apports continentaux sont negligeables, temoigne d’echanges sableux transversaux entre le large et l’estran. L’approche systemique et pluridisciplinaire adoptee permet de definir les relais de processus qui expliquent ces echanges, connus pour les plages de sables, mais rarement identifies pour les plages de galets.

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Effects of RU 486 (10 mg·kg –1 , per.os) were assessed at mid-pregnancy in the rat. One hour after RU 486 treatment, myometrial electrical activity stayed low. It increased from the 3rd hour after administration of RU 486 and a perfect synchronization of the bursts of the action potentials was observed from the 6th h to the 24th h. Tissular steroid hormones and PGF 2α , evaluated at hour 6 after RU 486 administration, showed a decrease of progesterone concentrations in both myometrium and uterus. Estradiol levels decreased in uterus whereas, PGF 2α levels increased in both myometrium and uterus. These results show for the first time that RU 486 strongly increases the myometrial electrical activity in the rat at mid-pregnancy. This action was closely related to E 2 , P 4 and PGF 2α concentrations.

A simple kinetic model for the transfer of radionuclide to freshwater fish was formulated based on physiological (blood and flow rates), anatomical (volume of tissue compartments) and thermodynamic (tissue-to-blood partition coefficients) parameters. The present study describes 54 Mn direct transfer to young rainbow trout and exemplifies this new approach for radioecology. The model was calibrated on uptake and depuration kinetics datasets obtained for 14 organs/tissues during a 12-week experiment. Organs were classified into three compartments: an input compartment (gills), a distribution/reservoir compartment (muscles, skeleton and skin) and an excretional function compartment (digestive system and liver). For the three compartments, the partition coefficients and the residence time of the pollutant were, respectively: 161 and 4 h, 87 and 1.5 days, and 1465 and 14 days. As an indirect validation technique, a steady-state concentration factor was calculated for the whole organism from the partition coefficient values and fractional volumes of the compartment. The value of 8 l kg−1 w.w. is similar to those reported in the literature.

The bathymetric range of seagrass beds represents a valuable biological indicator of littoral water quality. In order to contribute to the management of this natural heritage, an attempt was made to determine the status of Posidonia oceanica seagrass beds along the Mediterranean Corsican coast. The manual interpretation of images obtained using side scan sonar was used to accurately determine the lower depth limit of P. oceanica (-32m) and this work confirms the overall good quality of the littoral waters in this region of the Mediterranean. Particular structures which are directly linked to various human activities were identified manually, however, as were differences in sonogram texture. An attempt was thus made to automate processing of the sonograms in order to accurately identify and quantify these different formations.

In light of the essential role that seagrass beds play from an ecological and sedimentary point of view, mapping of these organisms should be carried out in order to clearly assess their distribution. Although a large number seagrass beds have been mapped, these generally only take into consideration the shallower formations (0–15 m) or those which are geographically very confined (

Clabaut Jean-Denis. Nord. Les vestiges du cloître de la collégiale Saint-Pierre de Lille. In: Bulletin Monumental, tome 156, n°4, année 1998. pp. 399-402.

The objective of this investigation was to examine the effects of 4-hydroxytamoxifen on the uterine activity. For this, we evaluated the electrical activity of the myometrium, chronically, in conscious unrestrained rats at mid-pregnancy. We also examined the tissular progesterone and 17β-estradiol concentrations in the myometrium and uterus 6 hours after administration of 4-hydroxytamoxifen. Comparison of myometrial electrical activities recorded during the control period with those obtained during the two periods (6 and 24 hours) after administration of4-hydroxytamoxifen (80 μg.kg−1, s.c.) showed an increase in simultaneity of uterine contractions (P < 0.01). Tissular steroid hormone measurement by radioimmunoassay shows a fall of progesterone in the myometrium (P < 0.001) and of 17β-estradiol in the uterus (P < 0.01), 6 hours after administration of 4-hydroxytamoxifen. In the myometrium, for 50% of animals, 17β-estradiol concentration decreased (P < 0.01) and for 50% of animals it increased (P < 0.05). The decrease in progesterone is significant in the myometrium and in the whole uterus (respectively P < 0.001 and P < 0.01), 24 hours after administration of 4-hydroxytamoxifen. The 17β-estradiol concentration significantly decreased for all animals in the myometrium (P < 0.01) and in the uterus (P < 0.01), after this time. It appears that variation in progesterone induces the activation of uterine motility and exerts an effect on some factors involved in the regulation of the rat myometrium at mid-pregnancy.

Treatment by a β1,β2-adrenoceptor antagonist has been much used during pathological pregnancies. These agents can reduce the oxygen consumption of the myocardium, increase the coronary blood flow towards ischemic heart areas and improve return of venous blood flow towards the heart. The aim of this study was to determine the mechanism of action of this agent and to investigate whether a total β-adrenoceptor antagonist could reduce the fetoplacental disorders elicited in streptozotocin-diabetic pregnant rats. Diabetes was engendered on day 7.5 of pregnancy, and the animals were studied on day 21. Untreated nondiabetic rats or nondiabetic rats treated with propranolol, a total β-adrenoceptor blocker (2 mg kg––1/day, i.p.), had a healthy placenta without vascular disturbances, with normal arterial blood velocity in the uterine artery, placenta, umbilical cord and fetal aorta, and showed eutrophic fetuses (3.9 ± 0.0 g, mean ± SEM). Untreated diabetic rats had severe placental lesions, with a reduction of arterial blood velocity in the uterine artery (p < 0.01), placenta (p < 0.01) and umbilical artery (p < 0.05), and exhibited fetal hypotrophy (2.3 ± 0.1 g, mean ± SEM, p < 0.001) compared with nondiabetic untreated rats. Treatment of diabetic rats with propranolol (2 mg kg––1/day, i.p.) enhanced fetal weight (3.66 ± 0.2 g) and slightly increased fetal insulin secretion, restored arterial blood velocity to control values in the uterine artery and fetal aorta and reduced placental lesions. In conclusion, our results suggest that the beneficial effects of propranolol were at least in part related to an improvement of uteroplacental hemodynamics; it induced a better redistribution of the blood towards the placenta and the fetal systemic circulation. Propranolol treatment could protect cell membranes against free oxygen radicals and lipid peroxidation, involved in the pathogenesis of ischemic injury in diabetes.

Clabaut Jean-Denis. Besançon. État des études sur les caves médiévales (XIIe-XVe siècle). In: Bulletin Monumental, tome 171, n°2, année 2013. pp. 151-155.

Coralligenous habitat and rhodoliths beds are very important in terms of biodiversity in the Mediterranean Sea. During an oceanographic campaign, carried out in northern Cap Corse, new coralligenous structures have been discovered. These structures, never previously identified in the Mediterranean Sea, are named “coralligenous atolls” because of their circular shape. The origin and growth dynamics of these atolls are still unknown but their form does not appear to result from hydrodynamic action and an anthropogenic origin also seems unlikely. However, this kind of shape seems rather closer to that of other circular structures (e.g. pockmarks) the origin of which is related to gaseous emissions. Further studies are needed to confirm this hypothesis through chemical analysis.

International audience; not available

International audience; not available

Dans le cadre de la surveillance du milieu marin du site électronucléaire de Penly (Seine-Maritime), le domaine benthique côtier de Dieppe à Criel-sur-Mer a fait l'objet en juin 2008 d'une prospection biomorphosédimentaire comme celles réalisées en 1988, 1992, 1996, 2000 et 2004. L'étude morpho-sédimentaire et les prélèvements faunistiques ont été réalisés du 4 au 12 mai 2008 à bord du N/O Thalia. Des techniques complémentaires ont été mises en œuvre : - le sonar à balayage latéral, couplé à un sondeur bathymétrique permettant une cartographie en continu des fonds - la benne Van Veen pour les prélèvements sédimentologiques - la benne Hamon pour les prélèvements faunistiques - le sondeur multifaisceaux pour réaliser un levé bathymétrique partiel Le principal résultat de ce travail conduit à l'élaboration de trois documents : - le rapport présentant les travaux réalisés, les techniques utilisées, les principaux résultats ainsi que leur interprétation en termes de dynamique. - une carte des formations superficielles à l'échelle 1/10 000 - une carte de l'évolution des fonds entre 2004 et 2008 à l'échelle 1/10 000

Complexity and the presence of stereogenic centers have been correlated with success as compounds transition from discovery through the clinic. Here we describe the synthesis of a library of pyran-containing macrocycles with a high degree of structural complexity and up to five stereogenic centers. A key feature of the design strategy was to use a modular synthetic route with three fragments that can be readily interchanged or “shuffled” to produce subtly different variants with distinct molecular shapes. A total of 352 macrocycles were synthesized ranging in size from 14- to 16-membered rings. In order to facilitate the generation of stereostructure-activity relationships, the complete matrix of stereoisomers was prepared for each macrocycle. Solid-phase assisted parallel solution-phase techniques were employed to allow for rapid analogue generation. An intramolecular nitrile-activated nucleophilic aromatic substitution reaction was used for the key macrocyclization step.

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It has been suggested that speciation on the basis of sexual selection is an important mechanism for the generation of new species for East African cichlids, where male body coloration is one of the major discriminatory factors used by females in mate choice. To gain insight into the molecular basis of cichlid coloration, we studied the Lake Malawi cichlid Pseudotropheus saulosi, comparing transcription in the bright blue skin of males to the yellow skin of females. Our cDNA microarray experiments identified 46 clones that exhibited expression differences between the two sexes, of which five were confirmed to be differentially expressed by relative quantitative real-time PCR (qRT-PCR). This gene list includes a representative from the endosomal-to-Golgi vesicle trafficking pathway, Coatomer protein complex, subunit zeta-1 (Copz-1), which is known to be a critical determinant of pigmentation in humans and zebrafish. With the support of microscopic images of the skin of these specimens, we interpret the transcriptional differences between the blue males and yellow females. Here, we provide insight into the putative functional diversification of genes involved in the coloration of cichlids and by extension, on the evolution of coloration in teleost fish.

International audience; In osteoporosis, bone loss is accompanied by greater adiposity in the marrow. Given the cellular proximity within the bone marrow, we wondered whether adipocytes might have a paracrine impact on osteoblast differentiation. To test this hypothesis, we cocultured adipocytes with osteoblasts derived from mesenchymal stem cells (MSCs) in the absence of direct cell contact and then analyzed gene expression changes in the osteoblastic population by using real-time reverse transcription polymerase chain reaction. We found that, upon coculture, MSC-derived osteoblasts showed appearance of adipogenic (lipoprotein lipase, leptin) and decrease of osteogenic (osteocalcin) mRNA markers. Our results indicate that in vitro, MSC-derived adipocytes are capable of inducing MSC-derived osteoblasts to differentiate to an adipocyte phenotype. These new data suggest that (i) transdifferentiation of committed osteoblasts into adipocytes may contribute to the increase in marrow fat content at the expense of bone-forming cells and (ii) this switch might be initiated by the adipocytes themselves.

SUMMARY The black-bellied African seedcracker, Pyrenestes ostrinus, exhibits a non-sex-related polymorphism in beak size that enables the small-, large-, and mega-billed morphs to utilize different trophic niches. The bill polymorphism between small- and large-billed individuals was previously shown to be under genetic control of a single autosomal locus with the allele for a large bill being dominant. African seedcrackers offer a novel opportunity to study the genetic basis of an adaptive polymorphism driven by disruptive selection and differential niche use in wild populations. In this study, we further explore the morphology and molecular development of the beak skeleton and of the cranial musculature in all morphs, both in adults and juveniles (nestlings). We find a close correlation in growth between the two tissues, even though juvenile birds (nestlings) of all morphs are fed a soft mostly insect diet by their parents until they fledge and become independent. Molecular and histological analyses suggest a heterochronic co-option of the mechanotransduction pathway into beak development program to produce the resource polymorphism. We also find that this plasticity is diminished after the nestling period. We suggest that a mutation affecting cranial muscle mass led to a corresponding change in jawbone morphology, allowing for apparent rapid evolution of novel functional adaptations of multiple tissues, a mechanism previously thought to be hard to achieve.

We report two cases of cutaneous granuloma induced by anti-TNF-α therapy: a 47-year-old man suffering from psoriatic arthritis treated with infliximab and a 56-year-old woman treated with adalimumab for polyarticular juvenile rheumatoid arthritis. The biospies confirmed the diagnosis of a ‘sarcoidosis-like’ reaction. No systemic involvement was observed. Such cases of noninfectious granulomatous diseases occurring during anti-TNF-α therapy are becoming increasingly frequent.