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981.
Blandine Destrez Emmanuelle Bichon Lauriane Rambaud Frdrique Courant Fabrice Monteau Gaud Pinel Jean-Philippe Antignac Bruno Le Bizec 《Steroids》2008,74(10-11):803-808
Boldenone is banned in the European Union (Directive 96/22/EC) as growth promoter for meat producing animals. Boldione (ADD), boldenone and boldenone esters (mainly the undecylenate form) are commercially available as anabolic preparations, either to the destination of human, horse or cattle. Since the late 90s, the natural occurrence of boldenone metabolites has been reported in cattle. According to EU regulation, the unambiguous demonstration of boldenone administration in bovine urine should be provided on the basis of boldenone identification in the corresponding conjugate fraction. An analytical method has been developed and validated according to current standards with main concern to the measurement of intact 17β-boldenone-sulphate. The analytical procedure included direct extraction–purification of target analyte on octadecylsilyl cartridges and direct detection of phase II metabolite by liquid chromatography (negative electrospray), tandem mass spectrometry (QqQ) or high resolution mass spectrometry (Orbitrap™). Decision limit (CCα) and detection capability (CCβ) were respectively 0.2 μg L−1 and 0.4 μg L−1 on triple quadrupole and 0.1 μg L−1 and 0.2 μg L−1 on hybrid system. The method was successfully applied to the analysis of incurred samples collected in different experiments. 17β-Boldenone-sulphate was measurable up to 36 h after oral administration of boldione, and 30 days after 17β-boldenone undecylenate intra-muscular injection. This conjugate form was never detected in non-treated animals, confirming its status of definitive candidate marker for boldenone administration in calf. 相似文献
982.
Esnault C Boulesteix M Duchemin JB Koffi AA Chandre F Dabiré R Robert V Simard F Tripet F Donnelly MJ Fontenille D Biémont C 《PloS one》2008,3(4):e1968
Background
Anopheles gambiae, a major vector of malaria, is widely distributed throughout sub-Saharan Africa. In an attempt to eliminate infective mosquitoes, researchers are trying to develop transgenic strains that are refractory to the Plasmodium parasite. Before any release of transgenic mosquitoes can be envisaged, we need an accurate picture of the differentiation between the two molecular forms of An. gambiae, termed M and S, which are of uncertain taxonomic status.Methodology/Principal Findings
Insertion patterns of three transposable elements (TEs) were determined in populations from Benin, Burkina Faso, Cameroon, Ghana, Ivory Coast, Madagascar, Mali, Mozambique, Niger, and Tanzania, using Transposon Display, a TE-anchored strategy based on Amplified Fragment Length Polymorphism. The results reveal a clear differentiation between the M and S forms, whatever their geographical origin, suggesting an incipient speciation process.Conclusions/Significance
Any attempt to control the transmission of malaria by An. gambiae using either conventional or novel technologies must take the M/S genetic differentiation into account. In addition, we localized three TE insertion sites that were present either in every individual or at a high frequency in the M molecular form. These sites were found to be located outside the chromosomal regions that are suspected of involvement in the speciation event between the two forms. This suggests that these chromosomal regions are either larger than previously thought, or there are additional differentiated genomic regions interspersed with undifferentiated regions. 相似文献983.
Airway and esophageal stenting in patients with advanced esophageal cancer and pulmonary involvement
Paganin F Schouler L Cuissard L Noel JB Becquart JP Besnard M Verdier L Rousseau D Arvin-Berod C Bourdin A 《PloS one》2008,3(8):e3101
Background
Most inoperable patients with esophageal-advanced cancer (EGC) have a poor prognosis. Esophageal stenting, as part of a palliative therapy management has dramatically improved the quality of live of EGC patients. Airway stenting is generally proposed in case of esophageal stent complication, with a high failure rate. The study was conducted to assess the efficacy and safety of scheduled and non-scheduled airway stenting in case of indicated esophageal stenting for EGC.Methods and Findings
The study is an observational study conducted in pulmonary and gastroenterology endoscopy units. Consecutive patients with EGC were referred to endoscopy units. We analyzed the outcome of airway stenting in patients with esophageal stent indication admitted in emergency or with a scheduled intervention. Forty-four patients (58±\−8 years of age) with esophageal stenting indication were investigated. Seven patients (group 1) were admitted in emergency due to esophageal stent complication in the airway (4 fistulas, 3 cases with malignant infiltration and compression). Airway stenting failed for 5 patients. Thirty-seven remaining patients had a scheduled stenting procedure (group 2): stent was inserted for 13 patients with tracheal or bronchial malignant infiltration, 12 patients with fistulas, and 12 patients with airway extrinsic compression (preventive indication). Stenting the airway was well tolerated. Life-threatening complications were related to group 1. Overall mean survival was 26+/−10 weeks and was significantly shorter in group 1 (6+/−7.6 weeks) than in group 2 (28+/−11 weeks), p<0.001). Scheduled double stenting significantly improved symptoms (95% at day 7) with a low complication rate (13%), and achieved a specific cancer treatment (84%) in most cases.Conclusion
Stenting the airway should always be considered in case of esophageal stent indication. A multidisciplinary approach with initial airway evaluation improved prognosis and decreased airways complications related to esophageal stent. Emergency procedures were rarely efficient in our experience. 相似文献984.
985.
Elise Jacquin Stéphanie Leclerc-Mercier Celine Judon Emmanuelle Blanchard Sylvie Fraitag 《Autophagy》2017,13(5):854-867
The modulation of canonical macroautophagy/autophagy for therapeutic benefit is an emerging strategy of medical and pharmaceutical interest. Many drugs act to inhibit autophagic flux by targeting lysosome function, while others were developed to activate the pathway. Here, we report the surprising finding that many therapeutically relevant autophagy modulators with lysosomotropic and ionophore properties, classified as inhibitors of canonical autophagy, are also capable of activating a parallel noncanonical autophagy pathway that drives MAP1LC3/LC3 lipidation on endolysosomal membranes. Further, we provide the first evidence supporting drug-induced noncanonical autophagy in vivo using the local anesthetic lidocaine and human skin biopsies. In addition, we find that several published inducers of autophagy and mitophagy are also potent activators of noncanonical autophagy. Together, our data raise important issues regarding the interpretation of LC3 lipidation data and the use of autophagy modulators, and highlight the need for a greater understanding of the functional consequences of noncanonical autophagy. 相似文献
986.
Chemical Composition,Antimicrobial and Insecticidal Activities of Flowers Essential Oils of Alpinia zerumbet (Pers.) B.L.Burtt & R.M.Sm. from Martinique Island
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Pauline Burger Vanessa Gonnot Laurent Boyer Fabrice Chandre Sandra Adenet Katia Rochefort Thomas Michel Xavier Fernandez 《化学与生物多样性》2017,14(4)
Alpinia species, used as ornamental plants and flavoring agents, are renowned for their therapeutic properties and their subsequent use in traditional medicines throughout the world. Alpinia zerumbet (Pers .) B.L.Burtt & R.M.Sm . is the most common Alpinia species encountered in Martinique. Several essential oils (EOs) obtained by hydrodistillation of A. zerumbet flowers collected in various locations on the island at different seasons were analysed to evaluate the influence of the collection period and area on the EOs’ chemical compositions and to assess their bioactivity. A combination of GC‐FID and GC/MS techniques was used to examine the volatile constituents, leading to the identification of a total of 71 components accounting for 97.8 – 99.3% of the respective total GC‐FID areas: among them, nineteen compounds were characterized for the first time in A. zerumbet EOs. The antimicrobial activity of these EOs was assessed against eight bacterial, yeast and fungal strains and two multi‐resistant strains: some significant bacteriostatic and fungistatic activities of A. zerumbet flower oils were evidenced. Finally, an interesting insecticidal activity of the flower EO was highlighted for the first time against Aedes aegypti. 相似文献
987.
Engineering Processes at the Interface of p‐Semiconductor for Enhancing the Open Circuit Voltage in p‐Type Dye‐Sensitized Solar Cells
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Ludovic Favereau Yann Pellegrin Lionel Hirsch Adèle Renaud Aurélien Planchat Errol Blart Guy Louarn Laurent Cario Stéphane Jobic Mohammed Boujtita Fabrice Odobel 《Liver Transplantation》2017,7(12)
To prevent the interfacial charge recombination between injected holes in the valence band and the redox mediator in the electrolyte in p‐type dye sensitized solar cells (p‐DSSC) the passivation of the recombination sites by organic insulator chenodeoxycholic acid (CDCA) layer is critically investigated in this study. Rather than classical coating of the semiconductor's surface by simultaneous co‐adsorption of CDCA during the dyeing step, two other methods are investigated. The first consists in dissolving CDCA in the electrolyte, while the second consists in spin coating an ethanol solution of CDCA onto the already dyed photocathode. In this study, different sensitizers, electrolytes, and p‐SCs, (NiO, CuGaO2) are explored. Analysis of the current/voltage curves and electrochemical impedance spectroscopy provides evidence that the role of the CDCA layer is to create a physical barrier to prevent the approach of the redox mediator from the NiO surface and consequently raise the open circuit voltage (Voc). The important finding of this study is the demonstration that the Voc in p‐DSSC is heavily limited by interfacial charge recombination and that higher Voc values much above 100 mV and as high as 500 mV can be attained with conventional materials (NiO) if this deleterious side reaction can be suppressed or diminished. 相似文献
988.
Fabrice Compain Nawel Aït-Ammar Françoise Botterel Laure Gibault Francoise Le Pimpec Barthes Eric Dannaoui 《Mycopathologia》2017,182(9-10):907-913
We report here a case of cavitary pneumonia due to Rhizopus homothallicus in a diabetic patient. This is the first proven case of R. homothallicus infection in Western countries and the third case described worldwide. The organism was isolated from lung biopsy and identified after amplification and sequencing of the internal transcribed spacer region. 相似文献
989.
Forest plant community as a driver of soil biodiversity: experimental evidence from collembolan assemblages through large‐scale and long‐term removal of oak canopy trees Quercus petraea
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Ludovic Henneron Michaël Aubert Fréderic Archaux Fabrice Bureau Yann Dumas François Ningre Claudine Richter Philippe Balandier Matthieu Chauvat 《Oikos》2017,126(3):420-434
Plant–soil interactions are increasingly recognized to play a major role in terrestrial ecosystems functioning. However, few studies to date have focused on slow dynamic ecosystems such as forests. As they are vertically stratified by multiple vegetation strata, canopy tree removal by thinning operations could alter forest plant community through tree canopy opening. Very little is known about cascading effects on soil biodiversity. We conducted a large‐scale, multi‐site assessment of collembolan assemblage response to long‐term canopy tree removal in sessile oak Quercus petraea temperate forests. A total of 33 experimental plots were studied covering a large gradient of canopy tree basal area, stand age and local abiotic contexts. Collembolan abundance strongly declined with canopy tree removal in early forest successional stage and this was mediated by negative effect of understory plant community composition changes, i.e. shift from moss and forb to tree seedling, fern, shrub and grass species. Negative effect of this composition shift on collembolan species richness was largely offset by positive effect of the increase in understory plant species richness. This gives support to both the plant mass‐ratio and functional diversity hypotheses. Collembolan functional groups had contrasting response patterns, which were mediated by different ecological factors. Epedaphic (r‐strategist) abundance and species richness increased with canopy tree removal in relation with the increase in understory plant species richness. In contrast, euedaphic (K‐strategist) abundance and species richness declined with canopy tree removal in early forest successional stage in relation with changes in understory plant community composition and species richness, as well as microclimatic conditions. Overall, our study provides experimental evidence that forest plant community can be a strong driver of collembolan assemblages. It also emphasizes the role of trees as foundation species of forest ecosystems that can shape soil biodiversity through their regulation of understory plant community and ecosystem abiotic conditions. 相似文献
990.
There is increasing awareness that many terrestrial and aquatic organisms are not strictly heterotrophic or autotrophic but rather mixotrophic. Mixotrophy is an intermediate nutritional strategy, merging autotrophy and heterotrophy to acquire organic carbon and/or other elements, mainly N, P or Fe. We show that both terrestrial and aquatic mixotrophs fall into three categories, namely necrotrophic (where autotrophs prey on other organisms), biotrophic (where heterotrophs gain autotrophy by symbiosis) and absorbotrophic (where autotrophs take up environmental organic molecules). Here we discuss their physiological and ecological relevance since mixotrophy is found in virtually every ecosystem and occurs across the whole eukaryotic phylogeny, suggesting an evolutionary pressure towards mixotrophy. Ecosystem dynamics tend to separate light from non‐carbon nutrients (N and P resources): the biological pump and water stratification in aquatic ecosystems deplete non‐carbon nutrients from the photic zone, while terrestrial plant successions create a canopy layer with light but devoid of non‐carbon soil nutrients. In both aquatic and terrestrial environments organisms face a grand écart (dancer's splits, i.e., the need to reconcile two opposing needs) between optimal conditions for photosynthesis vs. gain of non‐carbon elements. We suggest that mixotrophy allows adaptation of organisms to such ubiquist environmental gradients, ultimately explaining why mixotrophic strategies are widespread. 相似文献