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991.
Szinnai G Schachinger H Arnaud MJ Linder L Keller U 《American journal of physiology. Regulatory, integrative and comparative physiology》2005,289(1):R275-R280
Whether mental performance is affected by slowly progressive moderate dehydration induced by water deprivation has not been examined previously. Therefore, objective and subjective cognitive-motor function was examined in 16 volunteers (8 females, 8 males, mean age: 26 yr) twice, once after 24 h of water deprivation and once during normal water intake (randomized cross-over design; 7-day interval). Water deprivation resulted in a 2.6% decrease in body weight. Neither cognitive-motor function estimated by a paced auditory serial addition task, an adaptive 5-choice reaction time test, a manual tracking test, and a Stroop word-color conflict test nor neurophysiological function assessed by auditory event-related potentials P300 (oddball paradigm) differed (P > 0.1) between the water deprivation and the control study. However, subjective ratings of mental performance changed significantly toward increased tiredness (+1.0 points) and reduced alertness (-0.9 points on a 5-point scale; both: P < 0.05), and higher levels of perceived effort (+27 mm) and concentration (+28 mm on a 100-mm scale; both: P < 0.05) necessary for test accomplishment during dehydration. Several reaction time-based responses revealed significant interactions between gender and dehydration, with prolonged reaction time in women but shortened in men after water deprivation (Stroop word-color conflict test, reaction time in women: +26 ms, in men: -36 ms, P < 0.01; paced auditory serial addition task, reaction time in women +58 ms, in men -31 ms, P = 0.05). In conclusion, cognitive-motor function is preserved during water deprivation in young humans up to a moderate dehydration level of 2.6% of body weight. Sexual dimorphism for reaction time-based performance is present. Increased subjective task-related effort suggests that healthy volunteers exhibit cognitive compensating mechanisms for increased tiredness and reduced alertness during slowly progressive moderate dehydration. 相似文献
992.
Chalabi N Maurizis JC Le Corre L Delort L Bignon YJ Bernard-Gallon DJ 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,821(2):188-193
A new procedure for the quantification of phosphorylated BRCA1 (P-BRCA1) and BRCA2 (P-BRCA2) proteins in breast cell lines after different treatments was carried out. Cells were cultivated with [35S]-methionine and extracts subjected to three perfusion chromatographies. First heparin affinity chromatography purified cellular DNA-binding proteins. Subsequent specific immunoprecipitation of BRCA1 and BRCA2 proteins was performed with antibodies raised against BRCA1 or BRCA2. The immune complexes were isolated by protein A affinity chromatography. Phosphorylated BRCA1 or BRCA2 proteins were then purified with a Poros 20 AL column where anti-phosphothreonine and anti-phosphoserine antibodies were previously bound. The percentage of phosphorylated BRCA1 or BRCA2 proteins was calculated as follows: 100 x dpm of P-BRCA1 or P-BRCA2 eluted from the POROS 20AL column/total dpm eluted from POROS 20AL column. Treatment with 10 microM lycopene increased P-BRCA1 and P-BRCA2 in the breast tumor cell line MCF7 but not in MDA-MB-231 or MCF-10a, breast tumor or fibrocystic cell lines, respectively. 相似文献
993.
994.
Multifarious anchovy and sardine regimes in the Humboldt Current System during the last 150 years
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Renato Salvatteci David Field Dimitri Gutiérrez Tim Baumgartner Luc Ortlieb Abdel Sifeddine Daniel Grados Arnaud Bertrand 《Global Change Biology》2018,24(3):1055-1068
The Humboldt Current System (HCS) has the highest production of forage fish in the world, although it is highly variable and the future of the primary component, anchovy, is uncertain in the context of global warming. Paradigms based on late 20th century observations suggest that large‐scale forcing controls decadal‐scale fluctuations of anchovy and sardine across different boundary currents of the Pacific. We develop records of anchovy and sardine fluctuations since 1860 AD using fish scales from multiple sites containing laminated sediments and compare them with Pacific basin‐scale and regional indices of ocean climate variability. Our records reveal two main anchovy and sardine phases with a timescale that is not consistent with previously proposed periodicities. Rather, the regime shifts in the HCS are related to 3D habitat changes driven by changes in upwelling intensity from both regional and large‐scale forcing. Moreover, we show that a long‐term increase in coastal upwelling translates via a bottom‐up mechanism to top predators suggesting that the warming climate, at least up to the start of the 21st century, was favorable for fishery productivity in the HCS. 相似文献
995.
Arnaud Campidelli Chongsheng Qian Caroline Laroye Véronique Decot Lo?c Reppel Maud Daveni Danièle Bensoussan 《Cytotherapy》2018,20(4):524-531
Virus-specific T-cell (VST) infusion becomes a promising alternative treatment for refractory viral infections after hematopoietic stem cell transplantation (HSCT). However, VSTs are often infused during an immunosuppressive treatment course, especially corticosteroids, which are a first-line curative treatment of graft-versus-host disease (GVHD). We were interested in whether corticosteroids could affect adenovirus (ADV)-VST functions. After interferon (IFN)-γ based immunomagnetic selection, ADV-VSTs were in vitro expanded according to three different culture conditions: without methylprednisolone (MP; n?=?7), with a final concentration of MP 1?µg/mL (n?=?7) or MP 2?µg/mL (n?=?7) during 28?±?11 days. Efficacy and alloreactivity of expanded ADV-VSTs was controlled in vitro. MP transitorily inhibited ADV-VST early expansion. No impairment of specific IFN-γ secretion capacity and cytotoxicity of ADV-VSTs was observed in the presence of MP. However, specific proliferation and alloreactivity of ADV-VSTs were decreased in the presence of MP. Altogether, these results and the preliminary encouraging clinical experiences of co-administration of MP 1?mg/kg and ADV-VSTs will contribute to safe and efficient use of anti-viral immunotherapy. 相似文献
996.
997.
Mélanie Harzé Arnaud Monty Sylvain Boisson Carline Pitz Julia‐Maria Hermann Johannes Kollmann Grégory Mahy 《Restoration Ecology》2018,26(2):227-234
Persistence of restored populations depends on growth, reproduction, dispersal, local adaptation, and a suitable landscape pattern to foster metapopulation dynamics. Although the negative effects of habitat fragmentation on plant population dynamics are well understood, particularly in grasslands, the population traits that control grassland restoration are less known. We reviewed the use of population traits for evaluating grassland restoration success based on 141 publications (1986–2015). The results demonstrated that population demography was relatively well‐assessed but detailed studies providing information on key stages of the life cycle were lacking despite their importance in determining population viability. Vegetative and generative performances have been thoroughly investigated, notably the components of plant fitness, such as reproductive output, while genetic and spatial population structures were largely ignored. More work on the population effects of ecological restoration would be welcomed, particularly with a focus on population genetics. Targeted species were principally common and dominant natives, or invasive plants while rare or threatened species were poorly considered. Evaluation of ecological restoration should be conducted at different scales of ecological complexity, but so far, communities and ecosystems are over represented, and more focus should be directed towards a population approach as population traits are essential indicators of restoration success. 相似文献
998.
999.
Proton Ion Exchange Reaction in Li3IrO4: A Way to New H3+xIrO4 Phases Electrochemically Active in Both Aqueous and Nonaqueous Electrolytes
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Arnaud J. Perez Robin Beer Zifeng Lin Elodie Salager Pierre‐Louis Taberna Artem M. Abakumov Patrice Simon Jean‐Marie Tarascon 《Liver Transplantation》2018,8(13)
Progress over the past decade in Li‐insertion compounds has led to a new class of Li‐rich layered oxide electrodes cumulating both cationic and anionic redox processes. Pertaining to this new class of materials are the Li/Na iridate phases, which present a rich crystal chemistry. This work reports on a new protonic iridate phase H3+xIrO4 having a layered structure obtained by room temperature acid‐leaching of Li3IrO4. This new phase shows reversible charge storage properties of 1.5 e? per Ir atom with high rate capabilities in both nonaqueous (vs Li+/Li) and aqueous (vs capacitive carbon) media. It is demonstrated that Li‐insertion in carbonate LiPF6‐based electrolyte occurs through a classical reduction process (Ir5+ ? Ir3+), which is accompanied by a well‐defined structural transition. In concentrated H2SO4 electrolyte, this work provides evidence that the overall capacity of 1.7 H+ per Ir results from two additive redox processes with the low potential one showing ohmic limitations. Altogether, the room temperature protonation approach, which can be generalized to various Li‐rich phases containing either 3d, 4d or 5d metals, offers great opportunities for the judicious design of attractive electrode materials. 相似文献
1000.
Purification and characterization of an intracellular β-glucosidase from a new strain of Leuconostoc mesenteroides isolated from cassava 总被引:1,自引:1,他引:0
Y. Gueguen P. Chemardin P. Labrot A. Arnaud & P. Galzy 《Journal of applied microbiology》1997,82(4):469-476
The lactic acid bacterium, Leuconostoc mesenteroides, when grown on an arbutin-containing medium, was found to produce an intracellular β-glucosidase. The enzyme was purified by chromatofocusing, ion-exchange chromatography and gel filtration. The molecular mass of the purified intracellular β-glucosidase, as estimated by gel filtration, was 360 kDa. The tetrameric structure of the β-glucosidase was determined following treatment of the purified enzyme with dodecyl sulphate (SDS). The intracellular β-glucosidase exhibited optimum catalytic activity at 50°C and pH 6 with citrate–phosphate buffer, and 5·5 with phosphate buffer. The enzyme was active against glycosides with (1→4)-β, (1→4)-α and (1→6)-α linkage configuration. From Lineweaver–Burk plots, K m values of 0·07 mmol l−1 and 3·7 mmol l−1 were found for p -nitrophenyl-β- D -glucopyranoside and linamarin, respectively. The β-glucosidase was competitively inhibited by glucose and by D -gluconic acid–lactone and a glucosyl transferase activity was observed in the presence of ethanol. The β-glucosidase of Leuconostoc mesenteroides, with cyanogenic activity, could be of potential interest in cassava detoxification, by hydrolysing the cyanogenic glucosides present in cassava pulp. 相似文献