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971.
Chevalier F Centeno D Rofidal V Tauzin M Martin O Sommerer N Rossignol M 《Journal of proteome research》2006,5(3):512-520
Replicate 2-D gels were stained with four visible or fluorescent dyes using published procedures, and 48 co-detected spots were selected for contrasting values in abundance, M(r) and pI. Success rate of identification and sequence coverage were affected in a dye-dependent manner by the three parameters. Frequency of missed cleavages and recovery of sulfur-containing peptides also depended on the dye. Finally, the dataset was used to predict the number of proteins identifiable when integrating the differential contribution of each parameter. Sypro Ruby appeared to combine several favorable features: no dependence of the identification rate upon the physicochemical properties of proteins, no impact on frequency of missed cleavages, and a higher predicted identification rate. 相似文献
972.
Berry V Nicolas F 《IEEE/ACM transactions on computational biology and bioinformatics / IEEE, ACM》2006,3(3):289-302
Given a set of evolutionary trees on a same set of taxa, the maximum agreement subtree problem (MAST), respectively, maximum compatible tree problem (MCT), consists of finding a largest subset of taxa such that all input trees restricted to these taxa are isomorphic, respectively compatible. These problems have several applications in phylogenetics such as the computation of a consensus of phylogenies obtained from different data sets, the identification of species subjected to horizontal gene transfers and, more recently, the inference of supertrees, e.g., Trees Of Life. We provide two linear time algorithms to check the isomorphism, respectively, compatibility, of a set of trees or otherwise identify a conflict between the trees with respect to the relative location of a small subset of taxa. Then, we use these algorithms as subroutines to solve MAST and MCT on rooted or unrooted trees of unbounded degree. More precisely, we give exact fixed-parameter tractable algorithms, whose running time is uniformly polynomial when the number of taxa on which the trees disagree is bounded. The improves on a known result for MAST and proves fixed-parameter tractability for MCT. 相似文献
973.
974.
Previous microdialysis studies performed in rats have revealed a decrease of striatal dopamine and glutamate induced by nitrogen
narcosis. We sought to establish the hypothetical role of the glutamatergic corticostriatal pathway because of the glutamate
deficiency which occurs in the basal ganglia in this hyperbaric syndrome. Retrodialysis with 1 mM of Saclofen and 100 mM of
KCl in the prefrontal cortex under normobaric conditions led to an increase in striatal levels of glutamate by 95.2% and no
changes in dopamine levels. Under 3 MPa of nitrogen and with the infusion, the rate of striatal glutamate decreased by 51.3%,
to a greater extent than under pressurised nitrogen alone (−23.8%). The rate of dopamine decreased, which also occurred under
pressurised nitrogen (−36.9 and −31.4%, respectively). In conclusion, the function of the corticostriatal pathway is affected
by nitrogen under pressure. This suggests that the nitrogen-induced break point seems to be located at the glutamatergic striatopetal
neurons. 相似文献
975.
Diguta CF Rousseaux S Weidmann S Bretin N Vincent B Guilloux-Benatier M Alexandre H 《FEMS microbiology letters》2010,313(1):81-87
The aim of this study was to develop a system for rapid and accurate real-time quantitative PCR (qPCR) identification and quantification of Botrytis cinerea, one of the major pathogens present on grapes. The intergenic spacer (IGS) region of the nuclear ribosomal DNA was used to specifically detect and quantify B. cinerea. A standard curve was established to quantify this fungus. The qPCR reaction was based on the simultaneous detection of a specific IGS sequence and also contained an internal amplification control to compensate for variations in DNA extraction and the various compounds from grapes that inhibit PCR. In these conditions, the assay had high efficiency (97%), and the limit of detection was estimated to be 6.3 pg DNA (corresponding to 540 spores). Our method was applied to assess the effects of various treatment strategies against Botrytis in the vineyard. Our qPCR assay proved to be rapid, selective and sensitive and may be used to monitor Botrytis infection in vineyards. 相似文献
976.
Arindam Talukdar Ekaterina Morgunova Jianxin Duan Winfried Meining Nicolas Foloppe Lennart Nilsson Adelbert Bacher Boris Illarionov Markus Fischer Rudolf Ladenstein Mark Cushman 《Bioorganic & medicinal chemistry》2010,18(10):3518-3534
Virtual screening of a library of commercially available compounds versus the structure of Mycobacterium tuberculosis lumazine synthase identified 2-(2-oxo-1,2-dihydrobenzo[cd]indole-6-sulfonamido)acetic acid (9) as a possible lead compound. Compound 9 proved to be an effective inhibitor of M. tuberculosis lumazine synthase with a Ki of 70 μM. Lead optimization through replacement of the carboxymethylsulfonamide sidechain with sulfonamides substituted with alkyl phosphates led to a four-carbon phosphate 38 that displayed a moderate increase in enzyme inhibitory activity (Ki 38 μM). Molecular modeling based on known lumazine synthase/inhibitor crystal structures suggests that the main forces stabilizing the present benzindolone/enzyme complexes involve π–π stacking interactions with Trp27 and hydrogen bonding of the phosphates with Arg128, the backbone nitrogens of Gly85 and Gln86, and the side chain hydroxyl of Thr87. 相似文献
977.
Andrew D. Richardson T. Andy Black Philippe Ciais Nicolas Delbart Mark A. Friedl Nadine Gobron David Y. Hollinger Werner L. Kutsch Bernard Longdoz Sebastiaan Luyssaert Mirco Migliavacca Leonardo Montagnani J. William Munger Eddy Moors Shilong Piao Corinna Rebmann Markus Reichstein Nobuko Saigusa Enrico Tomelleri Rodrigo Vargas Andrej Varlagin 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1555):3227-3246
We use eddy covariance measurements of net ecosystem productivity (NEP) from 21 FLUXNET sites (153 site-years of data) to investigate relationships between phenology and productivity (in terms of both NEP and gross ecosystem photosynthesis, GEP) in temperate and boreal forests. Results are used to evaluate the plausibility of four different conceptual models. Phenological indicators were derived from the eddy covariance time series, and from remote sensing and models. We examine spatial patterns (across sites) and temporal patterns (across years); an important conclusion is that it is likely that neither of these accurately represents how productivity will respond to future phenological shifts resulting from ongoing climate change. In spring and autumn, increased GEP resulting from an ‘extra’ day tends to be offset by concurrent, but smaller, increases in ecosystem respiration, and thus the effect on NEP is still positive. Spring productivity anomalies appear to have carry-over effects that translate to productivity anomalies in the following autumn, but it is not clear that these result directly from phenological anomalies. Finally, the productivity of evergreen needleleaf forests is less sensitive to phenology than is productivity of deciduous broadleaf forests. This has implications for how climate change may drive shifts in competition within mixed-species stands. 相似文献
978.
979.
Beatrice Brembilla-Perrot Pierre Yves Zinzius Laurent Groben Luc Freysz Lucian Muresan Jerome Schwartz Raphael P Martins Soumaya Jarmouni Ibrahim Nossier Nicolas Sadoul Hugues Blangy Arnaud Terrier De La Chaise Pierre Louis Olivier Selton Daniel Beurrier Jean Marc Sellal 《Indian pacing and electrophysiology journal》2010,10(4):162-172
Background
The results of programmed ventricular stimulation (PVS) may change after myocardial infarction (MI). The objective was to study the factors that could predict the results of a second PVS.Methods
Left ventricular ejection fraction (LVEF) and QRS duration were determined and PVS performed within 3 to 14 years of one another (mean 7.5±5) in 50 patients studied systematically between 1 and 3 months after acute MI.Results
QRS duration increased from 120±23 ms to 132±29 (p 0.04). LVEF did not decrease significantly (36±12 % vs 37±13 %). Ventricular tachycardia with cycle length (CL) > 220ms (VT) was induced in 11 patients at PVS 1, who had inducible VT with a CL > 220 ms (8) or < 220 ms (ventricular flutter, VFl) (3) at PVS 2. VFl or fibrillation (VF) was induced in 14 patients at PVS 1 and remained inducible in 5; 5 patients had inducible VT and 4 had a negative 2nd PVS. 2. 25 patients had initially negative PVS; 7 had secondarily inducible VT, 4 a VFl/VF, 14 a negative PVS. Changes of PVS were related to initially increasing QRS duration and secondarily changes in LVEF and revascularization but not to the number of extrastimuli required to induce VFl.Conclusions
In patients without induced VT at first study, changes of PVS are possible during the life. Patients with initially long QRS duration and those who developed decreased LVEF are more at risk to have inducible monomorphic VT at 2nd study, than other patients. 相似文献980.