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121.
Alice L. Mauchline Maxime R. Hervé Samantha M. Cook 《Arthropod-Plant Interactions》2018,12(6):835-847
There is an urgent need to develop sustainable pest management systems to protect arable crops in order to replace the current over-reliance on synthetic insecticides. Semiochemicals are insect- or plant-derived chemicals that are used by organisms as information signals. Integrated pest management tools are currently in development that utilise semiochemicals to manipulate the behaviour of pest insects and their natural enemies to provide effective control of pests within the crop. These innovative tools usually require fewer inputs and can involve multiple elements, therefore reducing the likelihood of resistance developing compared with use of synthetic toxicants. We review here the life cycle of the pollen beetle Brassicogethes aeneus (previously known as Meligethes aeneus) which is a pest insect of oilseed rape (Brassica napus) and describe the current knowledge of any behaviour mediated by semiochemicals in this species. We discuss the behavioural processes where semiochemical-based control approaches may be appropriate and consider how these approaches could be incorporated into an integrated pest management strategy for this important arable crop. 相似文献
122.
Jean-Claude Brouet Jean-Louis Preud'homme Maxime Seligmann Jean Bernard 《BMJ (Clinical research ed.)》1973,4(5883):23-24
Acute blast crisis occurred in two patients with previously well-confirmed chronic lymphocytic leukaemia. The finding by direct immunofluorescence of membrane-bound monoclonal immunoglobulins on the surface of the blast cells showed that they were related to B cells in the same way as the proliferating lymphocytes in most patients with chronic lymphocytic leukaemia. In one patient the surface monoclonal IgM detected on both the lymphocytes and the blast cells had the same rheumatoid antibody activity, supporting the concept that the leukaemic cells found during the acute and chronic phases of the disease originated from the same clone. 相似文献
123.
124.
Fauvart M Braeken K Daniels R Vos K Ndayizeye M Noben JP Robben J Vanderleyden J Michiels J 《Biochimica et biophysica acta》2007,1774(9):1092-1098
Phylogenetic analysis of the superfamily of D-2-hydroxyacid dehydrogenases identified the previously unrecognized cluster of glyoxylate/hydroxypyruvate reductases (GHPR). Based on the genome sequence of Rhizobium etli, the nodulating endosymbiont of the common bean plant, we predicted a putative 3-phosphoglycerate dehydrogenase to exhibit GHPR activity instead. The protein was overexpressed and purified. The enzyme is homodimeric under native conditions and is indeed capable of reducing both glyoxylate and hydroxypyruvate. Other substrates are phenylpyruvate and ketobutyrate. The highest activity was observed with glyoxylate and phenylpyruvate, both having approximately the same kcat/Km ratio. This kind of substrate specificity has not been reported previously for a GHPR. The optimal pH for the reduction of phenylpyruvate to phenyllactate is pH 7. These data lend support to the idea of predicting enzymatic substrate specificity based on phylogenetic clustering. 相似文献
125.
Sylvain Boisson Michel-Pierre Faucon Soizig Le Stradic Bastien Lange Nathalie Verbruggen Olivier Garin Axel Tshomba Wetshy Maxime Séleck Wilfried Masengo Kalengo Mylor Ngoy Shutcha Grégory Mahy 《Plant and Soil》2017,413(1-2):261-273
Background and aims
Copper (Cu) rich soils derived from rocks of the Katangan Copperbelt in the south-eastern Democratic Republic of Congo (DRC) support a rich diversity of metallophytes including 550 heavy metal tolerant; 24 broad Cu soil endemic; and 33 strict Cu soil endemic plant species. The majority of the plant species occur on prominent Cu hills scattered along the copperbelt. Heavy metal mining on the Katangan Copperbelt has resulted in extensive degradation and destruction of the Cu hill ecosystems. As a result, approximately 80 % of the strict Cu endemic plant species are classified as threatened according to IUCN criteria and represent a conservation priority. Little is known about the soil Cu tolerance optimum of the Cu endemic plant species. The purpose of this study was to quantify the soil Cu concentration (Cu edaphic niche) of four Cu endemic plant species to inform soil propagation conditions and microhabitat site selection for planting of the species in Cu hill ecosystem restoration.Methods
The soil Cu concentration tolerance of Cu endemic plant species was studied including Crotalaria cobalticola (CRCO); Gladiolus ledoctei (GLLE); Diplolophium marthozianum (DIMA); and Triumfetta welwitschii var. rogersii (TRWE-RO). The in situ natural habitat distributions of the Cu endemic plant species with respect to soil Cu concentration (Cu edaphic niche) was calculated by means of a generalised additive model. Additionally, the seedling emergence and growth of the four Cu endemic plant species in three soil Cu concentrations was tested ex situ and the results were compared to that of the natural habitat soil Cu concentration optimum (Cu edaphic niche).Results
CRCO exhibited greater performance on the highest soil Cu concentration, consistent with its calculated Cu edaphic niche occurring at the highest soil Cu concentrations. In contrast, both DIMA and TRWE-RO exhibited greatest performance at the lowest soil Cu concentration, despite the calculated Cu edaphic niche occurring at moderate soil Cu concentrations. GLLE exhibited equal performances in the entire range of soil Cu concentrations.Conclusions
These results suggest that CRCO evolved via the edaphic specialization model where it is most competitive in Cu hill habitat with the highest soil Cu concentration. In comparison, DIMA and TRWE-RO appear to have evolved via the endemism refuge model, which indicates that the species were excluded into (i.e., took refuge in) the lower plant competition Cu hill habitat due to their inability to effectively compete with higher plant competition on normal soils. The soil Cu edaphic niche determined for the four species will be useful in conservation activities including informing soil propagation conditions and microhabitat site selection for planting of the species in Cu hill ecosystem restoration.126.
Guillaume Terral Thierry Champion François Debaene Olivier Colas Maxime Bourguet Elsa Wagner-Rousset 《MABS-AUSTIN》2017,9(8):1317-1326
Junctional adhesion molecule-A (JAM-A) is an adherens and tight junction protein expressed by endothelial and epithelial cells and associated with cancer progression. We present here the extensive characterization of immune complexes involving JAM-A antigen and three monoclonal antibodies (mAbs), including hz6F4-2, a humanized version of anti-tumoral 6F4 mAb identified by a functional and proteomic approach in our laboratory. A specific workflow that combines orthogonal approaches has been designed to determine binding stoichiometries along with JAM-A epitope mapping determination at high resolution for these three mAbs. Native mass spectrometry experiments revealed different binding stoichiometries and affinities, with two molecules of JAM-A being able to bind to hz6F4-2 and F11 Fab, while only one JAM-A was bound to J10.4. Surface plasmon resonance indirect competitive binding assays suggested epitopes located in close proximity for hz6F4-2 and F11. Finally, hydrogen-deuterium exchange mass spectrometry was used to precisely identify epitopes for all mAbs. The results obtained by orthogonal biophysical approaches showed a clear correlation between the determined epitopes and JAM-A binding characteristics, allowing the basis for molecular recognition of JAM-A by hz6F4-2 to be definitively established for the first time. Taken together, our results highlight the power of MS-based structural approaches for epitope mapping and mAb conformational characterization. 相似文献
127.
Courvoisier N Dougados M Cantagrel A Goupille P Meyer O Sibilia J Daures JP Combe B 《Arthritis research & therapy》2008,10(5):R106
Introduction
The objectives of this study were to determine the predictive factors of long-term radiographic outcome of rheumatoid arthritis (RA) and to describe the relationship between joint damage and disability over the course of the disease. 相似文献128.
Pagé D Balaux E Boisvert L Liu Z Milburn C Tremblay M Wei Z Woo S Luo X Cheng YX Yang H Srivastava S Zhou F Brown W Tomaszewski M Walpole C Hodzic L St-Onge S Godbout C Salois D Payza K Payza K 《Bioorganic & medicinal chemistry letters》2008,18(13):3695-3700
The preparation and evaluation of a novel class of CB2 agonists based on a benzimidazole moiety are reported. They showed binding affinities up to 1nM towards the CB2 receptor with partial to full agonist potencies. They also demonstrated good to excellent selectivity (>1000-fold) over the CB1 receptor. 相似文献
129.
Elke De Vuyst Nan Wang Elke Decrock Marijke De Bock Mathieu Vinken Marijke Van Moorhem Charles Lai Maxime Culot Vera Rogiers Romeo Cecchelli Christian C. Naus W. Howard Evans Luc Leybaert 《Cell calcium》2009,46(3):176-187
Connexin hemichannels have a low open probability under normal conditions but open in response to various stimuli, forming a release pathway for small paracrine messengers. We investigated hemichannel-mediated ATP responses triggered by changes of intracellular Ca2+ ([Ca2+]i) in Cx43 expressing glioma cells and primary glial cells. The involvement of hemichannels was confirmed with gja1 gene-silencing and exclusion of other release mechanisms. Hemichannel responses were triggered when [Ca2+]i was in the 500 nM range but the responses disappeared with larger [Ca2+]i transients. Ca2+-triggered responses induced by A23187 and glutamate activated a signaling cascade that involved calmodulin (CaM), CaM-dependent kinase II, p38 mitogen activated kinase, phospholipase A2, arachidonic acid (AA), lipoxygenases, cyclo-oxygenases, reactive oxygen species, nitric oxide and depolarization. Hemichannel responses were also triggered by activation of CaM with a Ca2+-like peptide or exogenous application of AA, and the cascade was furthermore operational in primary glial cells isolated from rat cortex. In addition, several positive feed-back loops contributed to amplify the responses. We conclude that an elevation of [Ca2+]i triggers hemichannel opening, not by a direct action of Ca2+ on hemichannels but via multiple intermediate signaling steps that are adjoined by distinct signaling mechanisms activated by high [Ca2+]i and acting to restrain cellular ATP loss. 相似文献
130.
Maxime Dauthieu Laurence Denaix Christophe Nguyen Frederic Panfili Frederic Perrot Martine Potin-Gautier 《Plant and Soil》2009,322(1-2):239-249
This study tested the hypothesis that Cd uptake is correlated with the shoot or root growth of Arabidopsis thaliana ecotype Columbia cultivated hydroponically at environmentally relevant Cd concentrations: 20, 100 and 350 nmol L?1. Growth of both roots and shoots were delayed at 350 nmol L?1. The rate of Cd uptake determined by spiking the nutrient solution with 109Cd for 24 h, was significantly correlated with the root growth rate. The fraction of Cd absorbed that was allocated to shoots was constant with time but decreased with increasing exposure to Cd. Autoradiography and gamma counting showed that Cd was preferentially allocated to developing leaves. Hence, the quantity of Cd in shoots depended both on the root growth, which probably governed the uptake, and on the maturity of the leaves, which may have determined the Cd allocated to shoots through changes in the transpiration stream. 相似文献