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161.
Leone M Bechah Y Meghari S Lepidi H Capo C Raoult D Mege JL 《FEMS immunology and medical microbiology》2007,50(3):396-400
The objective of this study was to investigate the effects of age on infection with Coxiella burnetii, the agent of Q fever. Bacterial burden and granuloma number were increased in the spleens of 14-month-old as compared with 1-month-old mice. This increase was not the result of an anti-inflammatory macrophage response, because inflammatory and anti-inflammatory cytokines were induced in macrophages from young mice but were repressed in mature mice. In addition, macrophage microbicidal competence was similar in mature and young mice. These results suggest the importance of individual host factors in the pathophysiology of an infectious disease such as Q fever. 相似文献
162.
Sylvain Legrand Theo Hendriks Jean-Louis Hilbert Marie-Christine Quillet 《BMC plant biology》2007,7(1):27
Background
Somatic embryogenesis (SE) is an asexual propagation pathway requiring a somatic-to-embryonic transition of differentiated somatic cells toward embryogenic cells capable of producing embryos in a process resembling zygotic embryogenesis. In chicory, genetic variability with respect to the formation of somatic embryos was detected between plants from a population of Cichorium intybus L. landrace Koospol. Though all plants from this population were self incompatible, we managed by repeated selfing to obtain a few seeds from one highly embryogenic (E) plant, K59. Among the plants grown from these seeds, one plant, C15, was found to be non-embryogenic (NE) under our SE-inducing conditions. Being closely related, we decided to exploit the difference in SE capacity between K59 and its descendant C15 to study gene expression during the early stages of SE in chicory. 相似文献163.
Wilfried Louisfrema Florence Porcher Jean-Louis Paillaud Pascale Massiani Anne Boutin 《Molecular simulation》2015,41(16-17):1371-1378
Using neutron scattering and Monte Carlo simulation, we investigate the distribution of cations in Na58Y faujasite upon (de)hydration. We introduce a new method for the assignment of cations to specific sites in molecular simulations from their local environment. This allows us to bypass the need of the coordinates of crystallographic sites, which vary as water adsorption induces changes in the zeolite framework structure. Although the agreement between experiments and simulation is excellent at high temperature, some differences are observed below 150°C. We show that these differences are due to the presence of water and that temperature itself as well as adsorption-induced deformation of the framework play a less important role. We demonstrate the migration of sodium to sites III upon water adsorption, not observed for other Si:Al ratios. 相似文献
164.
165.
Ganesana M Istarnboulie G Marty JL Noguer T Andreescu S 《Biosensors & bioelectronics》2011,30(1):43-48
This paper reports site-specific affinity immobilization of (His)6-tagged acetylcholinesterase (AChE) onto Ni/NiO nanoparticles for the development of an electrochemical screen-printed biosensor for the detection of organophosphate pesticides. The method is based on the specific affinity binding of the His-tagged enzyme to oxidized nickel nanoparticle surfaces in the absence of metal chelators. This approach allows stable and oriented attachment of the enzyme onto the oxidized nickel through the external His residue in one-step procedure, allowing for fast and sensitive detection of paraoxon in the concentration range from 10−8 to 10−13 M. A detection limit of 10−12 M for paraoxon was obtained after 20 min incubation. This method can be used as a generic approach for the immobilization of other His-tagged enzymes for the development of biosensors. 相似文献
166.
Cortès S Villiers CL Colpo P Couderc R Brakha C Rossi F Marche PN Villiers MB 《Biosensors & bioelectronics》2011,26(10):4162-4168
Microarrays are promising tools for cell isolation and detection. However, they have yet to be widely applied in biology. This stems from a lack of demonstration of their sensitivity and compatibility with complex biological samples, and a lack of proof that their use does not induce aberrant cellular effects. Herein, we characterized and optimized a recently developed technology associating antibody microarrays with surface plasmon resonance imaging (SPRi). Using a murine macrophage cell line we demonstrate the binding specificity of our antibody-microarrays and the correlation between SPRi signals and both the number of bound cells, and the level of expression of cell surface markers. Confocal microscopy reveals that cell binding to the chip through antibody-antigen interactions underwent morphological changes reflecting the density of the relevant cell surface marker without affecting cell viability as shown by fluorescent microscopy. The detection threshold of the microarray-SPRi system is lowered 10-fold by applying a polyethylene oxide film to the gold surface of the chip. This increased sensitivity allows the detection of cells representing as little as 0.5% of a mixed population. The potential of this method is illustrated by two applications: characterization of ligand-cell receptor interactions, allowing determination of receptor specificity, and analysis of peripheral blood mononuclear cells, demonstrating the suitability of this tool for the analysis of complex biological samples. 相似文献
167.
Stephanie Berthet Pascale Olivier Jean-Louis Montastruc Maryse Lapeyre-Mestre 《BMC clinical pharmacology》2011,11(1):1-6
Background
Spontaneous reporting of adverse drug reactions (ADRs) is an important method for pharmacovigilance, but under-reporting and poor quality of reports are major limitations. The aim of this study was to evaluate if repeated one-page ADR information letters affect (i) the reporting rate of ADRs and (ii) the quality of the ADR reports.Methods
All 151 primary healthcare units in the Region Västra Götaland, Sweden, were randomly allocated (1:1) to an intervention (n = 77) or a control group (n = 74). The intervention consisted of one-page ADR information letters administered at three occasions during 2008 to all physicians and nurses in the intervention units. The number of ADR reports received from the 151 units was registered, as was the quality of the reports, which was defined as high if the ADR was to be reported according to Swedish regulations, that is, if the ADR was (i) serious, (ii) unexpected, and/or (iii) related to the use of new drugs and not labelled as common in the Summary of Product Characteristics. A questionnaire was administered to evaluate if the ADR information letter had reached the intended recipient.Results
Before the intervention, no significant differences in reporting rate or number of high quality reports could be detected between the randomization groups. In 2008, 79 reports were sent from 37 intervention units and 52 reports from 30 control units (mean number of reports per unit ± standard deviation: 1.0 ± 2.5 vs. 0.7 ± 1.2, P = 0.34). The number of high quality reports was higher in intervention units than in control units (37 vs. 15 reports, 0.5 ± 0.9 vs. 0.2 ± 0.6, P = 0.048). According to the returned questionnaires (n = 1,292, response rate 57%), more persons in the intervention than in the control group had received (29% vs. 19%, P < 0.0001) and read (31% vs. 26%, P < 0.0001) an ADR information letter.Conclusions
This study suggests that repeated ADR information letters to physicians and nurses do not increase the ADR reporting rate, but may increase the number of high quality reports. 相似文献168.
John J. Sloggett Alexandra Magro François J. Verheggen Jean-Louis Hemptinne William D. Hutchison Eric W. Riddick 《BioControl》2011,56(4):643-661
We review the chemical ecology of the ladybird beetle Harmonia axyridis from the perspective of its invasiveness and the deleterious effects it exerts in the regions it has colonised. We outline
the nature and quantification of its chemical defence, and discuss the protection this provides against natural enemies, particularly
intraguild predators. We consider the role of infochemicals in location of prey, intraspecific communication and intraguild
interactions. We also discuss the role of prey allelochemicals in relation to H. axyridis extreme dietary generalism. Harmonia axyridis poses a number of practical problems for human health and well-being, including “ladybug taint” wine contamination and problems
resulting from large aggregations overwintering in buildings. We consider chemical insights into these issues and, in particular,
how attractants and repellents might help manage H. axyridis populations through a push–pull strategy. We conclude by discussing future perspectives for research. 相似文献
169.
Belleannee C Belghazi M Labas V Teixeira-Gomes AP Gatti JL Dacheux JL Dacheux F 《Proteomics》2011,11(10):1952-1964
Surface membrane proteins have a key role in the sequential interactions between spermatozoa and oocytes. The aim of this study was to characterize protein changes occurring during post-testicular differentiation using a new overall approach to study surface membrane proteins of spermatozoa. A dedicated protocol based on specific purification of surface membrane proteins labeled with sulfo-NHS-SS-biotin was developed for this purpose. Appropriate gel electrophoresis separation and purification methods combined with standard proteomic methods were then used to identify and quantify surface membrane proteins from immature and mature spermatozoa. Membrane-associated proteins were discriminated from integral membrane proteins by differential solubilization. Protein regionalization on the spermatozoon surface was achieved by comparative analysis of the surface protein extracts from the entire spermatozoa and from periacrosomal sperm plasma membranes. Identification of several known proteins and of new proteins related to the process of epididymal maturation showed the reliability of this protocol for specific purification of a subproteome and identification of new sperm membrane proteins. This approach opens up a new area in the search for male fertility markers. 相似文献
170.