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151.
Elsa Léger Gwenaël Vourc’h Laurence Vial Christine Chevillon Karen D. McCoy 《Experimental & applied acarology》2013,59(1-2):219-244
Today, we are witnessing changes in the spatial distribution and abundance of many species, including ticks and their associated pathogens. Evidence that these changes are primarily due to climate change, habitat modifications, and the globalisation of human activities are accumulating. Changes in the distribution of ticks and their invasion into new regions can have numerous consequences including modifications in their ecological characteristics and those of endemic species, impacts on the dynamics of local host populations and the emergence of human and livestock disease. Here, we review the principal causes for distributional shifts in tick populations and their consequences in terms of the ecological attributes of the species in question (i.e. phenotypic and genetic responses), pathogen transmission and disease epidemiology. We also describe different methodological approaches currently used to assess and predict such changes and their consequences. We finish with a discussion of new research avenues to develop in order to improve our understanding of these host–vector–pathogen interactions in the context of a changing world. 相似文献
152.
Joël Broyer 《Bird Study》2013,60(2):141-150
Capsule Mowing postponement in 25% of a meadow system may lead to improved but instable population dynamics in meadow birds. Aim To monitor the long‐term effects of mowing postponement on the abundance and territory density of meadow passerines in 25% of a 3000‐ha hay‐meadow area in the Saône Valley (eastern France). Methods From 1993 to 2009, passerine abundance was measured annually in 78 plots using point counts and territory density was assessed in two study areas by Territory Mapping. Results The programme of mowing postponement led to substantially increased passerine abundance and territory density, with the highest increase detected in Whinchats Saxicola rubetra. No positive trend was observed in Corn Buntings Emberiza calandra. Immediately after the increase in abundance, bird distribution within the study area was not influenced by the timing of mowing. The hatching success, assessed by the systematic observation of food carrying, was negatively influenced by early mowing (<40% recorded when >60% of the meadow area was already harvested on 1 July) or, in late mown areas, by high meadow passerine territory density (<40% when territory density was >10 per 10 ha). Hatching rate was usually higher in Whinchats than in Corn Buntings. Conclusion By improving meadow passerine breeding outputs and density, mowing postponement led to instable population dynamics with dominance of certain species and density‐dependent breeding success. 相似文献
153.
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155.
Marion Lahutte-Auboin Rémy Guillevin Jean-Pierre Françoise Jean-Noël Vallée Robert Costalat 《Acta biotheoretica》2013,61(1):79-89
WHO II low grade glioma evolves inevitably to anaplastic transformation. Magnetic resonance imaging is a good non-invasive way to watch it, by hemodynamic and metabolic modifications, thanks to multinuclear spectroscopy 1H/31P. In this work we study a multi-scale minimal model of hemodynamics and metabolism applied to the study of gliomas. This mathematical analysis leads us to a fast-slow system. The control of the position of the stationary point brings to the concept of domain of viability. Starting from this system, the equations bring to light the parameters that push glioma cells out of their domain of viability. Four fundamental factors are highlighted. The first two are cerebral blood flow and the rate of lactate transport through monocarboxylate transporters, which must be reduced in order to push glioma out of its domain of viability. Another factor is the intra arterial lactate, which must be increased. The last factor is pH, indeed a decrease of intra cellular pH could interfere with glioma growth. These reflections suggest that these four parameters could lead to new therapeutic strategies for the management of low grade gliomas. 相似文献
156.
Erick Francisco Rakotoniriana Mamy Rafamantanana Denis Randriamampionona Christian Rabemanantsoa Suzanne Urveg-Ratsimamanga Mondher El Jaziri Françoise Munaut Anne-Marie Corbisier Joëlle Quetin-Leclercq Stéphane Declerck 《Antonie van Leeuwenhoek》2013,103(1):121-133
Thirty-one endophytic bacteria isolated from healthy leaves of Centella asiatica were screened in vitro for their ability to reduce the growth rate and disease incidence of Colletotrichum higginsianum, a causal agent of anthracnose. Isolates of Cohnella sp., Paenibacillus sp. and Pantoea sp. significantly stimulated the growth rate of C. higginsianum MUCL 44942, while isolates of Achromobacter sp., Acinetobacter sp., Microbacterium sp., Klebsiella sp. and Pseudomonas putida had no influence on this plant pathogen. By contrast, Bacillus subtilis BCA31 and Pseudomonas fluorescens BCA08 caused a marked inhibition of C. higginsianum MUCL 44942 growth by 46 and 82 %, respectively. Cell-free culture filtrates of B. subtilis BCA31 and P. fluorescens BCA08 were found to contain antifungal compounds against C. higginsianum MUCL 44942. Inoculation assays on in vitro-cultured plants of C. asiatica showed that foliar application of B. subtilis BCA31, three days before inoculation with C. higginsianum MUCL 44942, significantly reduced incidence and severity of the disease. The role of endophytic bacteria in maintaining the apparent inactivity of C. higginsianum MUCL 44942 in C. asiatica grown in the wild is discussed. 相似文献
157.
Sébastien Tisné Yann Serrand Liên Bach Elodie Gilbault Rachid Ben Ameur Hervé Balasse Roger Voisin David Bouchez Mylène Durand‐Tardif Philippe Guerche Gaël Chareyron Jérôme Da Rugna Christine Camilleri Olivier Loudet 《The Plant journal : for cell and molecular biology》2013,74(3):534-544
Increased phenotyping accuracy and throughput are necessary to improve our understanding of quantitative variation and to be able to deconstruct complex traits such as those involved in growth responses to the environment. Still, only a few facilities are known to handle individual plants of small stature for non‐destructive, real‐time phenotype acquisition from plants grown in precisely adjusted and variable experimental conditions. Here, we describe Phenoscope, a high‐throughput phenotyping platform that has the unique feature of continuously rotating 735 individual pots over a table. It automatically adjusts watering and is equipped with a zenithal imaging system to monitor rosette size and expansion rate during the vegetative stage, with automatic image analysis allowing manual correction. When applied to Arabidopsis thaliana, we show that rotating the pots strongly reduced micro‐environmental disparity: heterogeneity in evaporation was cut by a factor of 2.5 and the number of replicates needed to detect a specific mild genotypic effect was reduced by a factor of 3. In addition, by controlling a large proportion of the micro‐environmental variance, other tangible sources of variance become noticeable. Overall, Phenoscope makes it possible to perform large‐scale experiments that would not be possible or reproducible by hand. When applied to a typical quantitative trait loci (QTL) mapping experiment, we show that mapping power is more limited by genetic complexity than phenotyping accuracy. This will help to draw a more general picture as to how genetic diversity shapes phenotypic variation. 相似文献
158.
Emmanuel Deau Yvonnick Loidreau Pascal Marchand Marie-Renée Nourrisson Nadège Loaëc Laurent Meijer Vincent Levacher Thierry Besson 《Bioorganic & medicinal chemistry letters》2013,23(24):6784-6788
The efficient synthesis of 7-substituted pyrido[2′,3′:4,5]furo[3,2-d]pyrimidin-4-amines and their N-aryl analogues is described. 3,5-Dibromopyridine was converted into 3-amino-6-bromofuro[3,2-b]pyridine-2-carbonitrile intermediate which was formylated with DMFDMA. Functionalization at position 7 of the tricyclic scaffold was accomplished, before or after cyclisation step, by palladium-catalyzed Suzuki–Miyaura cross-coupling while the pyrimidin-4-amines and N-aryl counterparts were synthesized by microwave-assisted formamide degradation and Dimroth rearrangement, respectively. The final products were evaluated for their potent inhibition of a series of five Ser/Thr kinases (CDK5/p25, CK1δ/ε, CLK1, DYRK1A, GSK3α/β). Compound 35 showed the best inhibitory activity with an IC50 value of 49 nM and proved to be specific to CLK1 among the panel of tested kinases. 相似文献
159.
Christophe Hano Sullivan Renouard Roland Molinié Cyrielle Corbin Esmatullah Barakzoy Joël Doussot Frédéric Lamblin Eric Lainé 《Bioorganic & medicinal chemistry letters》2013,23(10):3007-3012
Type 2 diabetes mellitus (T2DM) is one of the common global diseases. Flaxseed is by far the richest source of the dietary lignans (i.e., secoisolariciresinol diglucoside) which have been shown to delay the development of T2DM in animal models. Herein, we propose the first evidences for a mechanism of action involving the inhibition of the pancreatic α-amylase (EC 3.2.1.1) by flaxseed-derived lignans that could therefore constitute a promising nutraceutical for the prevention and the treatment of T2DM. 相似文献
160.
Colin H. MacKinnon Kevin Lau Jason D. Burch Yuan Chen Jonathon Dines Xiao Ding Charles Eigenbrot Alexander Heifetz Allan Jaochico Adam Johnson Joachim Kraemer Susanne Kruger Thomas M. Krülle Marya Liimatta Justin Ly Rosemary Maghames Christian A.G.N. Montalbetti Daniel F. Ortwine Zhonghua Pei 《Bioorganic & medicinal chemistry letters》2013,23(23):6331-6335
Inhibition of the non-receptor tyrosine kinase ITK, a component of the T-cell receptor signalling cascade, may represent a novel treatment for allergic asthma. Here we report the structure-based optimization of a series of benzothiazole amides that demonstrate sub-nanomolar inhibitory potency against ITK with good cellular activity and kinase selectivity. We also elucidate the binding mode of these inhibitors by solving the X-ray crystal structures of several inhibitor-ITK complexes. 相似文献