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101.
Papa Makhtar Drame Abdoulaye Diallo Anne Poinsignon Olayide Boussari Stephanie Dos Santos Vanessa Machault Richard Lalou Sylvie Cornelie Jean-Yves LeHesran Franck Remoue 《PloS one》2013,8(6)
Standard entomological methods for evaluating the impact of vector control lack sensitivity in low-malaria-risk areas. The detection of human IgG specific to Anopheles gSG6-P1 salivary antigen reflects a direct measure of human–vector contact. This study aimed to assess the effectiveness of a range of vector control measures (VCMs) in urban settings by using this biomarker approach. The study was conducted from October to December 2008 on 2,774 residents of 45 districts of urban Dakar. IgG responses to gSG6-P1 and the use of malaria VCMs highly varied between districts. At the district level, specific IgG levels significantly increased with age and decreased with season and with VCM use. The use of insecticide-treated nets, by drastically reducing specific IgG levels, was by far the most efficient VCM regardless of age, season or exposure level to mosquito bites. The use of spray bombs was also associated with a significant reduction of specific IgG levels, whereas the use of mosquito coils or electric fans/air conditioning did not show a significant effect. Human IgG response to gSG6-P1 as biomarker of vector exposure represents a reliable alternative for accurately assessing the effectiveness of malaria VCM in low-malaria-risk areas. This biomarker tool could be especially relevant for malaria control monitoring and surveillance programmes in low-exposure/low-transmission settings. 相似文献
102.
Chao-Wu Xiao Carla M. Wood Eleonora Swist Reiko Nagasaka Kurtis Sarafin Claude Gagnon Lois Fernandez Sylvie Faucher Hong-Xing Wu Laura Kenney Walisundera M. N. Ratnayake 《PloS one》2016,11(1)
Objectives
This study compared cardio-metabolic disease risk factors and their associations with serum vitamin D and omega-3 status in South Asian (SAC) and White Canadians (WC) living in Canada’s capital region.Methods
Fasting blood samples were taken from 235 SAC and 279 WC aged 20 to 79 years in Ottawa, and 22 risk factors were measured.Results
SAC men and women had significantly higher fasting glucose, insulin, homeostasis model assessment for insulin resistance (HOMA-IR), apolipoprotein B (ApoB), ratios of total (TC) to HDL cholesterol (HDLC) and ApoB to ApoA1, leptin, E-selectin, P-selectin, ICAM-1 and omega-3 (p < 0.05), but lower HDLC, ApoA1, vitamin D levels than WC (p < 0.05). SAC women had higher CRP and VEGF than WC women. Adequate (50–74.9 nmol/L) or optimal (≥ 75 nmol/L) levels of 25(OH)D were associated with lower BMI, glucose, insulin, HOMA-IR, TG, TC, low density lipoprotein cholesterol (LDLC), ApoB/ApoA1 ratio, CRP, leptin, and higher HDLC, ApoA1, omega-3 index, L-selectin levels in WC, but not in SAC. Intermediate (>4%-<8%) or high (≥ 8%) levels of omega-3 indices were related to lower E-selectin, P-selectin, ICAM-1 and higher HDLC, 25(OH)D levels in WC, but not in SAC. The BMIs of ≤ 25 kg/m2 were related to lower LDLC, ApoB, VEGF, creatinine and higher 25(OH)D in WC, but not in SAC.Conclusions
The associations of vitamin D, omega-3 status, BMI and risk factors were more profound in the WC than SAC. Compared to WC, vitamin D status and omega-3 index may not be good predictive risk factors for the prevalence of CVD and diabetes in SAC. 相似文献103.
Coralie Coudray-Meunier Audrey Fraisse Sandra Martin-Latil Sabine Delannoy Patrick Fach Sylvie Perelle 《PloS one》2016,11(1)
Human enteric viruses are recognized as the main causes of food- and waterborne diseases worldwide. Sensitive and quantitative detection of human enteric viruses is typically achieved through quantitative RT-PCR (RT-qPCR). A nanofluidic real-time PCR system was used to develop novel high-throughput methods for qualitative molecular detection (RT-qPCR array) and quantification of human pathogenic viruses by digital RT-PCR (RT-dPCR). The performance of high-throughput PCR methods was investigated for detecting 19 human pathogenic viruses and two main process controls used in food virology. The conventional real-time PCR system was compared to the RT-dPCR and RT-qPCR array. Based on the number of genome copies calculated by spectrophotometry, sensitivity was found to be slightly better with RT-qPCR than with RT-dPCR for 14 viruses by a factor range of from 0.3 to 1.6 log10. Conversely, sensitivity was better with RT-dPCR than with RT-qPCR for seven viruses by a factor range of from 0.10 to 1.40 log10. Interestingly, the number of genome copies determined by RT-dPCR was always from 1 to 2 log10 lower than the expected copy number calculated by RT-qPCR standard curve. The sensitivity of the RT-qPCR and RT-qPCR array assays was found to be similar for two viruses, and better with RT-qPCR than with RT-qPCR array for eighteen viruses by a factor range of from 0.7 to 3.0 log10. Conversely, sensitivity was only 0.30 log10 better with the RT-qPCR array than with conventional RT-qPCR assays for norovirus GIV detection. Finally, the RT-qPCR array and RT-dPCR assays were successfully used together to screen clinical samples and quantify pathogenic viruses. Additionally, this method made it possible to identify co-infection in clinical samples. In conclusion, given the rapidity and potential for large numbers of viral targets, this nanofluidic RT-qPCR assay should have a major impact on human pathogenic virus surveillance and outbreak investigations and is likely to be of benefit to public health. 相似文献
104.
Sylvie A. Quideau Anne C.S. McIntosh Charlotte E. Norris Emily Lloret Mathew J.B. Swallow Kirsten Hannam 《Journal of visualized experiments : JoVE》2016,(114)
Phospholipid fatty acids (PLFAs) are key components of microbial cell membranes. The analysis of PLFAs extracted from soils can provide information about the overall structure of terrestrial microbial communities. PLFA profiling has been extensively used in a range of ecosystems as a biological index of overall soil quality, and as a quantitative indicator of soil response to land management and other environmental stressors.The standard method presented here outlines four key steps: 1. lipid extraction from soil samples with a single-phase chloroform mixture, 2. fractionation using solid phase extraction columns to isolate phospholipids from other extracted lipids, 3. methanolysis of phospholipids to produce fatty acid methyl esters (FAMEs), and 4. FAME analysis by capillary gas chromatography using a flame ionization detector (GC-FID). Two standards are used, including 1,2-dinonadecanoyl-sn-glycero-3-phosphocholine (PC(19:0/19:0)) to assess the overall recovery of the extraction method, and methyl decanoate (MeC10:0) as an internal standard (ISTD) for the GC analysis. 相似文献
105.
Olaia Liñero Jean-Yves Cornu Frederic Candaudap Oleg S. Pokrovsky Sylvie Bussière Cécile Coriou Théophile Humann-Guilleminot Thierry Robert Stéphane Thunot Alberto de Diego Christophe Nguyen 《Plant and Soil》2016,408(1-2):163-181
Aims
This work concentrated on understanding the allocation of Cd recently taken up between the organs of sunflower at early and middle reproductive growth stages. The roles of transpiration and allometry were investigated.Methods
Sunflowers were grown hydroponically in greenhouse, being exposed to low concentrations of Cd (pCd2+ = 11.03). At flower bud and grain filling stages, plants were exposed for three days to 111Cd and at the same time, subjected or not to fans to increase the transpiration. The partitioning of 111Cd between plant organs measured by high resolution ICP-MS was then modelled.Results
Although the use of fans increased the plant water uptake and transpiration by about 20%, there were no significant effects on the partitioning of recent Cd. Most of the recent Cd was recovered in roots (60%) and only 2.8% were found in seeds (0.8% for the husk and 2.0% for the almonds). The sequestration of recent Cd in a plant organ was successfully explained by its biomass and except for leaves, by the biomass of other organs acting as competitive sinks.Conclusions
This work proposes a modelling approach for the partitioning of the labelled Cd between plant organs in sunflower.106.
García-Pérez Teresa Le Borgne Sylvie Revah Sergio 《Applied microbiology and biotechnology》2016,100(24):10637-10647
Applied Microbiology and Biotechnology - The operation and performance of a biotrickling filter for methanol (MeOH) and hydrogen sulfide (H2S) removal at acid pH was studied. Excess biomass in the... 相似文献
107.
Exploring Biotic and Abiotic Determinants of Nest Size in Mediterranean Great Tits (Parus major) and Blue Tits (Cyanistes caeruleus) 下载免费PDF全文
Marcel M. Lambrechts Jacques Blondel Cyril Bernard Samuel P. Caro Anne Charmantier Virginie Demeyrier Claire Doutrelant Gabrielle Dubuc‐Messier Amélie Fargevieille Christophe de Franceschi Pablo Giovannini Arnaud Grégoire Sylvie Hurtrez‐Boussès Annick Lucas Mark C. Mainwaring Pascal Marrot Adèle Mennerat Samuel Perret Philippe Perret 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(6):492-501
108.
109.
Candida albicans infection leads to barrier breakdown and a MAPK/NF‐κB mediated stress response in the intestinal epithelial cell line C2BBe1 下载免费PDF全文
110.
Silvain Pinaud Julien Portela David Duval Fanny C. Nowacki Marie-Aude Olive Jean-Fran?ois Allienne Richard Galinier Nolwenn M. Dheilly Sylvie Kieffer-Jaquinod Guillaume Mitta André Théron Benjamin Gourbal 《PLoS pathogens》2016,12(1)
Discoveries made over the past ten years have provided evidence that invertebrate antiparasitic responses may be primed in a sustainable manner, leading to the failure of a secondary encounter with the same pathogen. This phenomenon called “immune priming” or "innate immune memory" was mainly phenomenological. The demonstration of this process remains to be obtained and the underlying mechanisms remain to be discovered and exhaustively tested with rigorous functional and molecular methods, to eliminate all alternative explanations. In order to achieve this ambitious aim, the present study focuses on the Lophotrochozoan snail, Biomphalaria glabrata, in which innate immune memory was recently reported. We provide herein the first evidence that a shift from a cellular immune response (encapsulation) to a humoral immune response (biomphalysin) occurs during the development of innate memory. The molecular characterisation of this process in Biomphalaria/Schistosoma system was undertaken to reconcile mechanisms with phenomena, opening the way to a better comprehension of innate immune memory in invertebrates. This prompted us to revisit the artificial dichotomy between innate and memory immunity in invertebrate systems. 相似文献