Contribution à l'étude des micromammifères de la chaîne des Pyrénées : particularités de l'extrême oriental (Massif des Albères)

La faune des micromammifères de la chaîne des Pyrénées, composée de 32 espèces, présente des variations selon les versants. L'extrême oriental (Albères) montre la composition la plus basse. Ce déficit serait encore plus accentué sans la présence de la hêtraie de la réserve naturelle de la Massane qui détermine la plus grande richesse du versant septentrional (19 espèces) comparée au versant méridional(14 espèces). La présente contribution, résultat de prospections réalisées durant ces vingt dernières années, analyse comparativement pour la première fois, les communautés de micromammifères -insectivores et rongeurs- des versants français et espagnol de l'extrémité orientale soulignant sa spécificité i l'intérieur de la chaîne des Pyrénées. La succession des faunes de micromammifères a été étudiée après l'incendie dans divers rnilieux méditerranéens du Massif des Albères. Parallblement, la composition et la dynamique des populations ont été observées dans des zones témoins non brulées. La vitesse de recolonisation dépend de la capacité de dispersion, des migrations allochtones et des stratégies démographiques chez quatre espèces: C. russula, A. sylvaticus, M. spretus, et E. quercinus. La musaraigne C. suaveolens est citée, pour la première fois en Catalogne ibérique.Small mammals fauna from the Pyrenean Mountains, composed of 32 species, presents variations according the different slopes. The oriental part (Alberes) shows the poorest composition. The deficit would become even more noticeable without the presence of the beech-grove of the Natural Reserve of "La Massane", which determines the greatest richness of the northern slope (19 species) versus the southern one (14 species). The present contribution, out coming from prospectings carried out for the last twenty years, analyses comparably for the first time small mammals communities -insectivores and rodents- of the French and Spanish slopes of the oriental part, emphasising their specificity inside the Pyrenean Chain. Succession of small mammals faunas has been studied after fire in diverse Mediterranean areas of Alberes massif. In a parallel way, the composition and dynamic of populations have been observed in witness unburnt zones. The quickness of recolonization depends on dispersion capacity, allochthonous migrations and demographical strategies of four species: C. russula, A. sylvaticus, M. spretus and E. quercinus. The shrew C. suaveolens is mentioned for the first time in Iberian Cataloni

The Timing of the Shrew: Continuous Melatonin Treatment Maintains Youthful Rhythmic Activity in Aging Crocidura russula

BACKGROUND:Laboratory conditions nullify the extrinsic factors that determine the wild expected lifespan and release the intrinsic or potential lifespan. Thus, wild animals reared in a laboratory often show an increased lifespan, and consequently an increased senescence phase. Senescence is associated with a broad suite of physiological changes, including a decreased responsiveness of the circadian system. The time-keeping hormone melatonin, an important chemical player in this system, is suspected to have an anti-aging role. The Greater White-toothed shrew Crocidura russula is an ideal study model to address questions related to aging and associated changes in biological functions: its lifespan is short and is substantially increased in captivity; daily and seasonal rhythms, while very marked the first year of life, are dramatically altered during the senescence process which starts during the second year. Here we report on an investigation of the effects of melatonin administration on locomotor activity of aging shrews. METHODOLOGY/PRINCIPAL FINDINGS:1) The diel fluctuations of melatonin levels in young, adult and aging shrews were quantified in the pineal gland and plasma. In both, a marked diel rhythm (low diurnal concentration; high nocturnal concentration) was present in young animals but then decreased in adults, and, as a result of a loss in the nocturnal production, was absent in old animals. 2) Daily locomotor activity rhythm was monitored in pre-senescent animals that had received either a subcutaneous melatonin implant, an empty implant or no implant at all. In non-implanted and sham-implanted shrews, the rhythm was well marked in adults. A marked degradation in both period and amplitude, however, started after the age of 14-16 months. This pattern was considerably delayed in melatonin-implanted shrews who maintained the daily rhythm for significantly longer. CONCLUSIONS:This is the first long term study (>500 days observation of the same individuals) that investigates the effects of continuous melatonin delivery. As such, it sheds new light on the putative anti-aging role of melatonin by demonstrating that continuous melatonin administration delays the onset of senescence. In addition, the shrew appears to be a promising mammalian model for elucidating the precise relationships between melatonin and aging

The small mammals of the department of Oriental Pyrenees.

peer reviewedIn the Pyrénées-Orientales, distribution of small mammals and relative densities of the different species are governed by the lanscape: coastal and brackish water vegetation, agricultural areas in the Roussillon plain, mediterranean land vegetation, forests of lower montain and subalpine levels, alpine pastures. Finally topographic plays its role in the linkage of biocenoses and in particular by the orientation of the three main valleys with the resulting distribution of solar impact: mediterranean species attaining relatively high altitudes in warm sites paralleled by mountain species descending fairly low on shady slopes. In the area studied, the subalpine and low mountain levels are characterized by the absence of Crocidurinae, and the presence of Sorex "araneus", Sorex minutus, Microtus arvalis, Arvicola terrestris and Clethrionomys glareolus. The mediterranean level is characterized by the absence of Sorex and the presence of Pitymys duodecimcostatus and Mus spretus. Crocidura russula, C. suaveolens and Suncus etruscus occur in considerable numbers, but their presence is not typical of the mediterranean biome. The submediterranean level (transition zone) is the richest in terms of species number, as it comprises the zone of faunal overlap according to local solar impact

Polyp malignancy classification with CNN features based on Blue Laser and Linked Color Imaging

In-vivo classification of benign and pre-malignant polyps is a laborious task that requires histophatology confirmation. In an effort to improve the quality of clinical diagnosis, medical experts have come up with visual models with only limited success. In this paper, a classification approach is proposed to differentiate between polypmalignancy, using features extracted from the Global Average Pooling (GAP) layer of a pre-trained Convolutional Neural Network (CNNs) . Two recently developed endoscopic modalities are used to improve the pipeline prediction: Blue Laser Imaging (BLI) and Linked Color Imaging (LCI). Furthermore, a new strategy of per-class data augmentation is adopted to tackle the differences of unbalanced class distribution. The results are compared with a more general approach, showing how artificial examples can improve results on highly unbalanced problems. For the same reason, the combined features for each patient are extracted and trained using several machine learning classifiers without CNNs. Moreover to speed up computation, a recent GPU based Support Vector Machine (SVM) scheme is employed to substantially decrease the overload during training time. The presented methodology shows the feasibility of using the LCI and BLI techniques for automatic polypmalignancy classification and facilitates future advances to limit the need for time-consuming and costly histopathological assessment

Impact of Soil Sealing on Soil Carbon Sequestration, Water Storage Potentials and Biomass Productivity in Functional Urban Areas of the European Union and the United Kingdom

The negative impacts of soil sealing are numerous, from withdrawing fertile soil from biomass production to modifying the microclimate and decreasing biodiversity. Many of the processes are interrelated and propagate further undesirable consequences from local to global levels. Three issues are especially important from the viewpoint of multiscale ecological cycles and consequent environmental impacts. One is soil organic carbon (SOC), the other is soil water management and the third is biomass productivity. In this study, we assessed the lost carbon sequestration potential due to soil sealing in functional Urban Areas (FUAs) of Europe, the potential effect of soil sealing on the topsoil to hold water to its full capacity and the loss of biomass productivity potential. Findings revealed that one-fifth of the area of soil that became sealed between 2012 and 2018 was of high productivity potential, and almost two-thirds was of medium productivity potential. New soil sealing caused a loss of carbon sequestration potential estimated at 4 million tons of carbon of the FUAs and also caused an estimated potential loss of water-holding capacity of 668 million m3

Triplet network for classification of benign and pre-malignant polyps

Colorectal polyps are critical indicators of colorectal cancer (CRC). Classification of polyps during colonoscopy is still a challenge for which many medical experts have come up with visual models, albeit with limited success. An early detection of CRC prevents further complications in the colon, which makes identification of abnormal tissue a crucial step during routinary colonoscopy. In this paper, a classification approach is proposed to differentiate between benign and pre-malignant polyps using features learned from a Triplet Network architecture. The study includes a total of 154 patients, with 203 different polyps. For each polyp an image is acquired with White Light (WL), and additionally with two recent endoscopic modalities:Blue Laser Imaging (BLI) and Linked Color Imaging (LCI). The network is trained with the associated triplet loss, allowing the learning of non-linear features, which prove to be a highly discriminative embedding, leading to excellent results with simple linear classifiers. Additionally, the acquisition of multiple polyps with WL, BLI and LCI, enables the combination of the posterior probabilities, yielding a more robust classification result. Threefold cross-validation is employed as validation method and accuracy, sensitivity, specificity and area under the curve (AUC) are computed as evaluation metrics. While our approach achieves a similar classification performance compared to state-of-the-art methods, it has a much lower inference time (from hours to seconds, on a single GPU). The increased robustness and much faster execution facilitates future advances towards patient safety and may avoid time-consuming and costly histhological assessment.</p

A human CD5+ B cell clone that secretes an idiotype-specific high affinity IgM monoclonal antibody.

We previously demonstrated the occurrence of a naturally arisen human anti-idiotypic B cell clone, that we transformed with EBV (EBV383). We show evidence that EBV383 not only expresses the CD5 surface Ag, but also contains the 2.7-kb mRNA transcript encoding this protein. In addition, we show the presence of the 3.6-kb mRNA precursor. Most Ig produced by CD5+ B cells are polyreactive natural IgM antibodies encoded by unmutated copies of germline VH genes. However, in this study we present data demonstrating the monoreactive high affinity character of the anti-idiotypic antibody (mAb383) produced by EBV383. These data are in agreement with our previous observations, showing that the VH chain of mAb383 is encoded by an extensive somatically mutated VHV gene in a way that is consistent with an Ag-driven immune response. A possible role for this remarkable anti-idiotypic antibody in the maintenance of B cell memory is discussed

Lentivirus-mediated transgene delivery to the hippocampus reveals sub-field specific differences in expression

<p>Abstract</p> <p>Background</p> <p>In the adult hippocampus, the granule cell layer of the dentate gyrus is a heterogeneous structure formed by neurons of different ages, morphologies and electrophysiological properties. Retroviral vectors have been extensively used to transduce cells of the granule cell layer and study their inherent properties in an intact brain environment. In addition, lentivirus-based vectors have been used to deliver transgenes to replicative and non-replicative cells as well, such as post mitotic neurons of the CNS. However, only few studies have been dedicated to address the applicability of these widespread used vectors to hippocampal cells in vivo. Therefore, the aim of this study was to extensively characterize the cell types that are effectively transduced in vivo by VSVg-pseudotyped lentivirus-based vectors in the hippocampus dentate gyrus.</p> <p>Results</p> <p>In the present study we used Vesicular Stomatitis Virus G glycoprotein-pseudotyped lentivirual vectors to express EGFP from three different promoters in the mouse hippocampus. In contrast to lentiviral transduction of pyramidal cells in CA1, we identified sub-region specific differences in transgene expression in the granule cell layer of the dentate gyrus. Furthermore, we characterized the cell types transduced by these lentiviral vectors, showing that they target primarily neuronal progenitor cells and immature neurons present in the sub-granular zone and more immature layers of the granule cell layer.</p> <p>Conclusion</p> <p>Our observations suggest the existence of intrinsic differences in the permissiveness to lentiviral transduction among various hippocampal cell types. In particular, we show for the first time that mature neurons of the granule cell layer do not express lentivirus-delivered transgenes, despite successful expression in other hippocampal cell types. Therefore, amongst hippocampal granule cells, only adult-generated neurons are target for lentivirus-mediated transgene delivery. These properties make lentiviral vectors excellent systems for overexpression or knockdown of genes in neuronal progenitor cells, immature neurons and adult-generated neurons of the mouse hippocampus in vivo.</p

CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research