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71.
Junior physicians mainly learn during their observation in the operative room. The senior physicians evaluate them based on the same kind of observation. Knowledge transfer evaluation is thus done without quantitative methods and it mainly lies on a subjective assessment. In this paper, we present some recent techniques used to objectively evaluate medical gestures. The classical techniques used are Hidden Markov Models (HMM) or Dynamic Time Warping (DTW). Both techniques lies on the temporal analysis of the gestures. We proposed here a technique based on the arc length parametrization in order to analyze the gestures in space which is more appropriate because it gives information about the shape of the gestures independently of the chosen coordinate system. 相似文献
72.
Pascal Hingamp Nigel Grimsley Silvia G Acinas Camille Clerissi Lucie Subirana Julie Poulain Isabel Ferrera Hugo Sarmento Emilie Villar Gipsi Lima-Mendez Karoline Faust Shinichi Sunagawa Jean-Michel Claverie Hervé Moreau Yves Desdevises Peer Bork Jeroen Raes Colomban de Vargas Eric Karsenti Stefanie Kandels-Lewis Olivier Jaillon Fabrice Not Stéphane Pesant Patrick Wincker Hiroyuki Ogata 《The ISME journal》2013,7(9):1678-1695
Nucleo-cytoplasmic large DNA viruses (NCLDVs) constitute a group of eukaryotic viruses that can have crucial ecological roles in the sea by accelerating the turnover of their unicellular hosts or by causing diseases in animals. To better characterize the diversity, abundance and biogeography of marine NCLDVs, we analyzed 17 metagenomes derived from microbial samples (0.2–1.6 μm size range) collected during the Tara Oceans Expedition. The sample set includes ecosystems under-represented in previous studies, such as the Arabian Sea oxygen minimum zone (OMZ) and Indian Ocean lagoons. By combining computationally derived relative abundance and direct prokaryote cell counts, the abundance of NCLDVs was found to be in the order of 104–105 genomes ml−1 for the samples from the photic zone and 102–103 genomes ml−1 for the OMZ. The Megaviridae and Phycodnaviridae dominated the NCLDV populations in the metagenomes, although most of the reads classified in these families showed large divergence from known viral genomes. Our taxon co-occurrence analysis revealed a potential association between viruses of the Megaviridae family and eukaryotes related to oomycetes. In support of this predicted association, we identified six cases of lateral gene transfer between Megaviridae and oomycetes. Our results suggest that marine NCLDVs probably outnumber eukaryotic organisms in the photic layer (per given water mass) and that metagenomic sequence analyses promise to shed new light on the biodiversity of marine viruses and their interactions with potential hosts. 相似文献
73.
Bryche Jean-François Gillibert Raymond Barbillon Grégory Gogol Philippe Moreau Julien Lamy de la Chapelle Marc Bartenlian Bernard Canva Michael 《Plasmonics (Norwell, Mass.)》2016,11(2):601-608
Plasmonics - In this paper, we report on an improved enhancement of the surface-enhanced Raman scattering (SERS) effect. Such improvement is obtained by using a continuous gold film (underlayer),... 相似文献
74.
Effects of food abundance and early clutch predation on reproductive timing in a high Arctic shorebird exposed to advancements in arthropod abundance
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Jeroen Reneerkens Niels Martin Schmidt Olivier Gilg Jannik Hansen Lars Holst Hansen Jérôme Moreau Theunis Piersma 《Ecology and evolution》2016,6(20):7375-7386
Climate change may influence the phenology of organisms unequally across trophic levels and thus lead to phenological mismatches between predators and prey. In cases where prey availability peaks before reproducing predators reach maximal prey demand, any negative fitness consequences would selectively favor resynchronization by earlier starts of the reproductive activities of the predators. At a study site in northeast Greenland, over a period of 17 years, the median emergence of the invertebrate prey of Sanderling Calidris alba advanced with 1.27 days per year. Yet, over the same period Sanderling did not advance hatching date. Thus, Sanderlings increasingly hatched after their prey was maximally abundant. Surprisingly, the phenological mismatches did not affect chick growth, but the interaction of the annual width and height of the peak in food abundance did. Chicks grew especially better in years when the food peak was broad. Sanderling clutches were most likely to be depredated early in the season, which should delay reproduction. We propose that high early clutch predation may favor a later reproductive timing. Additionally, our data suggest that in most years food was still abundant after the median date of emergence, which may explain why Sanderlings did not advance breeding along with the advances in arthropod phenology. 相似文献
75.
Hyong Woo Choi Murli Manohar Patricia Manosalva Miaoying Tian Magali Moreau Daniel F. Klessig 《PLoS pathogens》2016,12(3)
Damage-associated molecular pattern molecules (DAMPs) signal the presence of tissue damage to induce immune responses in plants and animals. Here, we report that High Mobility Group Box 3 (HMGB3) is a novel plant DAMP. Extracellular HMGB3, through receptor-like kinases BAK1 and BKK1, induced hallmark innate immune responses, including i) MAPK activation, ii) defense-related gene expression, iii) callose deposition, and iv) enhanced resistance to Botrytis cinerea. Infection by necrotrophic B. cinerea released HMGB3 into the extracellular space (apoplast). Silencing HMGBs enhanced susceptibility to B. cinerea, while HMGB3 injection into apoplast restored resistance. Like its human counterpart, HMGB3 binds salicylic acid (SA), which results in inhibition of its DAMP activity. An SA-binding site mutant of HMGB3 retained its DAMP activity, which was no longer inhibited by SA, consistent with its reduced SA-binding activity. These results provide cross-kingdom evidence that HMGB proteins function as DAMPs and that SA is their conserved inhibitor. 相似文献
76.
Thomas C Moreau F Dieterle M Hoffmann C Gatti S Hofmann C Van Troys M Ampe C Steinmetz A 《The Journal of biological chemistry》2007,282(46):33599-33608
Actin filament bundling, i.e. the formation of actin cables, is an important process that relies on proteins able to directly bind and cross-link subunits of adjacent actin filaments. Animal cysteine-rich proteins and their plant counterparts are two LIM domain-containing proteins that were recently suggested to define a new family of actin cytoskeleton regulators involved in actin filament bundling. We here identified the LIM domains as responsible for F-actin binding and bundling activities of the tobacco WLIM1. The deletion of one of the two LIM domains reduced significantly, but did not entirely abolish, the ability of WLIM1 to bind actin filaments. Individual LIM domains were found to interact directly with actin filaments, although with a reduced affinity compared with the native protein. Variants lacking the C-terminal or the inter-LIM domain were only weakly affected in their F-actin stabilizing and bundling activities and trigger the formation of thick cables containing tightly packed actin filaments as does the native protein. In contrast, the deletion of one of the two LIM domains negatively impacted both activities and resulted in the formation of thinner and wavier cables. In conclusion, we demonstrate that the LIM domains of WLIM1 are new autonomous actin binding and bundling modules that cooperate to confer WLIM1 high actin binding and bundling activities. 相似文献
77.
Proteomics analysis of cytokine-induced dysfunction and death in insulin-producing INS-1E cells: new insights into the pathways involved 总被引:1,自引:0,他引:1
D'Hertog W Overbergh L Lage K Ferreira GB Maris M Gysemans C Flamez D Cardozo AK Van den Bergh G Schoofs L Arckens L Moreau Y Hansen DA Eizirik DL Waelkens E Mathieu C 《Molecular & cellular proteomics : MCP》2007,6(12):2180-2199
Cytokines released by islet-infiltrating immune cells play a crucial role in beta-cell dysfunction and apoptotic cell death in the pathogenesis of type 1 diabetes and after islet transplantation. RNA studies revealed complex pathways of genes being activated or suppressed during this beta-cell attack. The aim of the present study was to analyze protein changes in insulin-producing INS-1E cells exposed to inflammatory cytokines in vitro using two-dimensional DIGE. Within two different pH ranges we observed 2214 +/- 164 (pH 4-7) and 1641 +/- 73 (pH 6-9) spots. Analysis at three different time points (1, 4, and 24 h of cytokine exposure) revealed that the major changes were taking place only after 24 h. At this time point 158 proteins were altered in expression (4.1%, n = 4, p < or = 0.01) by a combination of interleukin-1beta and interferon-gamma, whereas only 42 and 23 proteins were altered by either of the cytokines alone, giving rise to 199 distinct differentially expressed spots. Identification of 141 of these by MALDI-TOF/TOF revealed proteins playing a role in insulin secretion, cytoskeleton organization, and protein and RNA metabolism as well as proteins associated with endoplasmic reticulum and oxidative stress/defense. We investigated the interactions of these proteins and discovered a significant interaction network (p < 1.27e-05) containing 42 of the identified proteins. This network analysis suggests that proteins of different pathways act coordinately in a beta-cell dysfunction/apoptotic beta-cell death interactome. In addition the data suggest a central role for chaperones and proteins playing a role in RNA metabolism. As many of these identified proteins are regulated at the protein level or undergo post-translational modifications, a proteomics approach, as performed in this study, is required to provide adequate insight into the mechanisms leading to beta-cell dysfunction and apoptosis. The present findings may open new avenues for the understanding and prevention of beta-cell loss in type 1 diabetes. 相似文献
78.
79.
Bonnet F Dequae-Merchadou L Taupin JL Sire S Dupon M Ragnaud JM Lacoste D Texier-Maugein J Romagné F Dabis F Pellegrin JL Moreau JF 《Microbes and infection / Institut Pasteur》1999,1(10):771-776
In a retrospective study, an increase in double-negative (CD3+ CD4- CD8-) (DN) T lymphocytes has been shown to be an independent predictor of disseminated Mycobacterium avium complex (D.MAC) infection in patients with less than 100 CD4+ T cells per mm3. To better characterize this cell expansion, a prospective study was designed. From July 1995 to April 1997, 206 HIV-infected patients with less than 100 CD4+ T cells per mm3 were prospectively followed up and immunophenotyped. The median followup was 1.1 year (+/-0.5 year), and 14 new D.MAC infections were diagnosed among 84 first AIDS-defining events. In univariate and multivariate analyses, D.MAC infections were the only opportunistic infection with a significant increase in DN T-cell percentage (median = 6.6; range = 1.7 to 24.5, P = 0.004) compared with patients without any opportunistic infection. This alteration in T-lymphocyte count could constitute a predictor for D.MAC infection in clinical practice. 相似文献
80.
The Ras protein activates at least three different pathways during early development. Two of them regulate mesodermal gene expression and the third is thought to participate in the control of actin cytoskeleton dynamics via the Ral protein. From a yeast two-hybrid screen of a Xenopus maternal cDNA library, we identified the Xenopus orthologue of the Ral interacting protein (RLIP, RIP1 or RalBP1), a putative effector of small G protein Ral. Previously, we observed that a constitutively activated form of Ral GTPase (XralB G23V) induced bleaching of the animal hemisphere and disruption of the cortical actin cytoskeleton. To demonstrate that RLIP is the effector of RalB in early development, we show that the artificial targeting of RLIP to the membrane induces a similar phenotype to that of activated RalB. We show that overexpression of the Ral binding domain (RalBD) of XRLIP, which binds to the effector site of Ral, acts in competition with the endogenous effector of Ral and protects against the destructive effect of XralB G23V on the actin cytoskeleton. In contrast, the XRLIP has a synergistic effect on the activated form of XralB, which is dependent on the RalBD of RLIP. We provide evidence for the involvement of RLIP by way of its RalBD on the dynamics of the actin cytoskeleton and propose that signalling from Ral to RLIP is required for gastrulation. 相似文献