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101.
Dominique Delforge Barbara Gillon Muriel Art Janique Dewelle Martine Raes José Remacle 《Letters in Peptide Science》1998,5(2-3):87-91
A synthetic adhesion protein was designed by chemical grafting of the RGD tailed cyclic peptide cyclo[-d-Val-Arg-Gly-Asp-Glu(-Ahx-Tyr-Cys-NH2)-] on the carrier protein bovine serum albumin (BSA). The cyclic conformation of the RGD motif grafted on the protein mimics the conformation of the motif displayed in native adhesion proteins such as fibronectin. The adhesion of the cells on polystyrene coated with the conjugate BSA–peptide was similar or even better than the one obtained when the proadhesive protein fibronectin was coated on the plates. Results also indicated that covalent coupling of the peptide on BSA is not absolutely required, since simple adsorption of the peptide on the protein coated on plates was efficient for enhancing cell adhesion. These results show that polystyrene support can be reconditioned with conformationally constrained RGD peptides to enhance cell adhesion on solid supports. The same methodology can be adapted for the development of new biomaterials based on the recognition of specific peptides. 相似文献
102.
Jessica Lebenberg Alain Lalande Patrick Clarysse Irene Buvat Christopher Casta Alexandre Cochet Constantin Constantinidès Jean Cousty Alain de Cesare Stephanie Jehan-Besson Muriel Lefort Laurent Najman Elodie Roullot Laurent Sarry Christophe Tilmant Frederique Frouin Mireille Garreau 《PloS one》2015,10(8)
This work aimed at combining different segmentation approaches to produce a robust and accurate segmentation result. Three to five segmentation results of the left ventricle were combined using the STAPLE algorithm and the reliability of the resulting segmentation was evaluated in comparison with the result of each individual segmentation method. This comparison was performed using a supervised approach based on a reference method. Then, we used an unsupervised statistical evaluation, the extended Regression Without Truth (eRWT) that ranks different methods according to their accuracy in estimating a specific biomarker in a population. The segmentation accuracy was evaluated by estimating six cardiac function parameters resulting from the left ventricle contour delineation using a public cardiac cine MRI database. Eight different segmentation methods, including three expert delineations and five automated methods, were considered, and sixteen combinations of the automated methods using STAPLE were investigated. The supervised and unsupervised evaluations demonstrated that in most cases, STAPLE results provided better estimates than individual automated segmentation methods. Overall, combining different automated segmentation methods improved the reliability of the segmentation result compared to that obtained using an individual method and could achieve the accuracy of an expert. 相似文献
103.
Konstantinos Arapis Jean Baptiste Cavin Laura Gillard Fran?oise Cluzeaud Philippe Lettéron Robert Ducroc Johanne Le Beyec Muriel Hourseau Anne Couvelard Jean-Pierre Marmuse Maude Le Gall André Bado 《PloS one》2015,10(3)
Whereas the remodeling of intestinal mucosa after bariatric surgeries has been the matter of numerous studies to our knowledge, very few reported on the remodeling of the residual gastric mucosa. In this study, we analyzed remodeling of gastric mucosa after Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) in rats. Diet-induced obese rats were subjected to RYGB, VSG or sham surgical procedures. All animals were assessed for food intake, body-weight, fasting blood, metabolites and hormones profiling, as well as insulin and glucose tolerance tests before and up to 5 weeks post-surgery. Remodeling of gastric tissues was analyzed by routine histology and immunohistochemistry studies, and qRT-PCR analyses of ghrelin and gastrin mRNA levels. In obese rats with impaired glucose tolerance, VSG and RYGB caused substantial weight loss and rats greatly improved their oral glucose tolerance. The remaining gastric mucosa after VSG and gastric pouch (GP) after RYGB revealed a hyperplasia of the mucous neck cells that displayed a strong immunoreactivity for parietal cell H+/K+-ATPase. Ghrelin mRNA levels were reduced by 2-fold in remaining fundic mucosa after VSG and 10-fold in GP after RYGB. In the antrum, gastrin mRNA levels were reduced after VSG in line with the reduced number of gastrin positive cells. This study reports novel and important observations dealing with the remaining gastric mucosa after RYGB and VSG. The data demonstrate, for the first time, a hyperplasia of the mucous neck cells, a transit cell population of the stomach bearing differentiating capacities into zymogenic and peptic cells. 相似文献
104.
Sophie De Decker Muriel Vray Viridiana Sistek Bhety Labeau Antoine Enfissi Dominique Rousset Séverine Matheus 《PLoS neglected tropical diseases》2015,9(3)
Considering the short lifetime of IgA antibodies in serum and the key advantages of antibody detection ELISAs in terms of sensitivity and specificity, Bio-Rad has just developed a new ELISA test based on the detection of specific anti-dengue IgA. This study has been carried out to assess the performance of this Platelia Dengue IgA Capture assay for dengue infection detection. A total of 184 well-characterized samples provided by the French Guiana NRC sera collection (Laboratory of Virology, Institut Pasteur in French Guiana) were selected among samples collected between 2002 and 2013 from patients exhibiting a dengue-like syndrome. A first group included 134 sera from confirmed dengue-infected patients, and a second included 50 sera from non-dengue infected patients, all collected between day 3 and day 15 after the onset of fever. Dengue infection diagnoses were all confirmed using reference assays by direct virological identification using RT-PCR or virus culture on acute sera samples or on paired acute-phase sera samples of selected convalescent sera. This study revealed: i) a good overall sensitivity and specificity of the IgA index test, i.e., 93% and 88% respectively, indicating its good correlation to acute dengue diagnosis; and ii) a good concordance with the Panbio IgM capture ELISA. Because of the shorter persistence of dengue virus-specific IgA than IgM, these results underlined the relevance of this new test, which could significantly improve dengue diagnosis accuracy, especially in countries where dengue virus is (hyper-) endemic. It would allow for additional refinement of dengue diagnostic strategy. 相似文献
105.
Ga?tan Vanier Franziska Hempel Philippe Chan Michael Rodamer David Vaudry Uwe G. Maier Patrice Lerouge Muriel Bardor 《PloS one》2015,10(10)
Monoclonal antibodies (mAbs) represent actually the major class of biopharmaceuticals. They are produced recombinantly using living cells as biofactories. Among the different expression systems currently available, microalgae represent an emerging alternative which displays several biotechnological advantages. Indeed, microalgae are classified as generally recognized as safe organisms and can be grown easily in bioreactors with high growth rates similarly to CHO cells. Moreover, microalgae exhibit a phototrophic lifestyle involving low production costs as protein expression is fueled by photosynthesis. However, questions remain to be solved before any industrial production of algae-made biopharmaceuticals. Among them, protein heterogeneity as well as protein post-translational modifications need to be evaluated. Especially, N-glycosylation acquired by the secreted recombinant proteins is of major concern since most of the biopharmaceuticals including mAbs are N-glycosylated and it is well recognized that glycosylation represent one of their critical quality attribute. In this paper, we assess the quality of the first recombinant algae-made mAbs produced in the diatom, Phaeodactylum tricornutum. We are focusing on the characterization of their C- and N-terminal extremities, their signal peptide cleavage and their post-translational modifications including N-glycosylation macro- and microheterogeneity. This study brings understanding on diatom cellular biology, especially secretion and intracellular trafficking of proteins. Overall, it reinforces the positioning of P. tricornutum as an emerging host for the production of biopharmaceuticals and prove that P. tricornutum is suitable for producing recombinant proteins bearing high mannose-type N-glycans. 相似文献
106.
Christine Demanche Manjula Deville Johan Michaux Véronique Barriel Claire Pin?on Cécile Marie Aliouat-Denis Muriel Pottier Christophe No?l Eric Viscogliosi El Moukhtar Aliouat Eduardo Dei-Cas Serge Morand Jacques Guillot 《PloS one》2015,10(4)
Pneumocystis fungi represent a highly diversified biological group with numerous species, which display a strong host-specificity suggesting a long co-speciation process. In the present study, the presence and genetic diversity of Pneumocystis organisms was investigated in 203 lung samples from woodmice (Apodemus sylvaticus) collected on western continental Europe and Mediterranean islands. The presence of Pneumocystis DNA was assessed by nested PCR at both large and small mitochondrial subunit (mtLSU and mtSSU) rRNA loci. Direct sequencing of nested PCR products demonstrated a very high variability among woodmouse-derived Pneumocystis organisms with a total number of 30 distinct combined mtLSU and mtSSU sequence types. However, the genetic divergence among these sequence types was very low (up to 3.87%) and the presence of several Pneumocystis species within Apodemus sylvaticus was considered unlikely. The analysis of the genetic structure of woodmouse-derived Pneumocystis revealed two distinct groups. The first one comprised Pneumocystis from woodmice collected in continental Spain, France and Balearic islands. The second one included Pneumocystis from woodmice collected in continental Italy, Corsica and Sicily. These two genetic groups were in accordance with the two lineages currently described within the host species Apodemus sylvaticus. Pneumocystis organisms are emerging as powerful tools for phylogeographic studies in mammals. 相似文献
107.
108.
Multiple-use marine protected areas (MPAs) are used to manage marine resources, allocate space to different users and reduce
conflicts while protecting marine biodiversity. In the Mediterranean, MPA managers are increasingly interested in containing
the effects of coastal recreation within underwater trails, but snorkelers impacts on the surrounding ecosystem remain largely
unknown. In a Mediterranean MPA, an underwater snorkeling trail was established to concentrate snorkelers and increase their
awareness of marine habitats and species. The high level of summer frequentation may have negative impacts on the surrounding
environment through trampling on the sessile flora or disturbance to the vagile fauna. We used a before-after-control-impact
(BACI) design to analyse these potential human impacts. The structure of macroalgae and fish assemblages were used as indicators.
Permutational multivariate analyses of variance (PERMANOVA) were carried out to assess potential temporal and spatial changes
of the indicators between the trail and a control location within the adjacent no-take/no-use area. Fish communities and macroalgae
were subjected to natural temporal trends but no significant impacts of snorkelers were found. Four reasons could explain
the absence of snorkelers impact on the surrounding marine environment: (1) the absence of very fragile organisms within the
trail (and the control no-take/no-use area) such as gorgonians or bryozoans; (2) the life cycle of the algae with a natural
decreasing trend in summer, corresponding to the trail opening period; (3) only a few snorkelers are practicing apnoea; and
(4) the information at the entrance and along the trail may influence the snorkelers’ behaviour. 相似文献
109.
Latitudinal and altitudinal patterns of plant community diversity on mountain summits across the tropical Andes 下载免费PDF全文
Francisco Cuesta Priscilla Muriel Luis Daniel Llambí Stephan Halloy Nikolay Aguirre Stephan Beck Julieta Carilla Rosa Isela Meneses Soledad Cuello Alfredo Grau Luis E. Gámez Javier Irazábal Jorge Jácome Ricardo Jaramillo Lirey Ramírez Natalia Samaniego David Suárez‐Duque Natali Thompson Alfredo Tupayachi Paul Viñas Karina Yager María T. Becerra Harald Pauli William D. Gosling 《Ecography》2017,40(12):1381-1394
The high tropical Andes host one of the richest alpine floras of the world, with exceptionally high levels of endemism and turnover rates. Yet, little is known about the patterns and processes that structure altitudinal and latitudinal variation in plant community diversity. Herein we present the first continental‐scale comparative study of plant community diversity on summits of the tropical Andes. Data were obtained from 792 permanent vegetation plots (1 m2) within 50 summits, distributed along a 4200 km transect; summit elevations ranged between 3220 and 5498 m a.s.l. We analyzed the plant community data to assess: 1) differences in species abundance patterns in summits across the region, 2) the role of geographic distance in explaining floristic similarity and 3) the importance of altitudinal and latitudinal environmental gradients in explaining plant community composition and richness. On the basis of species abundance patterns, our summit communities were separated into two major groups: Puna and Páramo. Floristic similarity declined with increasing geographic distance between study‐sites, the correlation being stronger in the more insular Páramo than in the Puna (corresponding to higher species turnover rates within the Páramo). Ordination analysis (CCA) showed that precipitation, maximum temperature and rock cover were the strongest predictors of community similarity across all summits. Generalized linear model (GLM) quasi‐Poisson regression indicated that across all summits species richness increased with maximum air temperature and above‐ground necromass and decreased on summits where scree was the dominant substrate. Our results point to different environmental variables as key factors for explaining vertical and latitudinal species turnover and species richness patterns on high Andean summits, offering a powerful tool to detect contrasting latitudinal and altitudinal effects of climate change across the tropical Andes. 相似文献
110.
Martina Ferraguti Sergio Magallanes Jéssica Jiménez-Peñuela Josué Martínez-de la Puente Luz Garcia-Longoria Jordi Figuerola Jaime Muriel Tamer Albayrak Staffan Bensch Camille Bonneaud Rohan H. Clarke Gábor Á. Czirják Dimitar Dimitrov Kathya Espinoza John G. Ewen Farah Ishtiaq Wendy Flores-Saavedra László Zsolt Garamszegi Olof Hellgren Dita Horakova Kathryn P. Huyvaert Henrik Jensen Asta Križanauskienė Marcos R. Lima Charlene Lujan-Vega Eyðfinn Magnussen Lynn B. Martin Kevin D. Matson Anders Pape Møller Pavel Munclinger Vaidas Palinauskas Péter L. Pap Javier Pérez-Tris Swen C. Renner Robert Ricklefs Sergio Scebba Ravinder N. M. Sehgal Manuel Soler Eszter Szöllősi Gediminas Valkiūnas Helena Westerdahl Pavel Zehtindjiev Alfonso Marzal 《Global Ecology and Biogeography》2023,32(5):809-823