Quantification of six phytoestrogens at the nanogram per liter level in aqueous environmental samples using 13C3-labeled internal standards     

Erbs M  Hoerger CC  Hartmann N  Bucheli TD 《Journal of agricultural and food chemistry》2007,55(21):8339-8345

In light of the estrogenic potentials and the recent concentration levels found for six phytoestrogens in surface waters, detailed monitoring and assessment of potential input sources are required. An accurate, precise, and sensitive HPLC-MS/MS analytical method incorporating five (13)C 3-labeled internal standards for the quantification of these plant estrogens in various aqueous environmental samples is presented here for the first time. The compounds investigated included biochanin A, daidzein, equol, formononetin, genistein, and coumestrol. The use of [ (13)C 3]biochanin A, [ (13)C 3]daidzein, [ (13)C 3]equol, [ (13)C 3]formononetin, and [ (13)C 3]genistein ensured an accurate quantification of the target analytes unaffected by matrix effects and analyte losses. Absolute method recoveries for all analytes ranged from 63 to 105%, from 63 to 99%, and from 73 to 133%, relative recoveries from 90 to 132%, from 89 to 139%, and from 89 to 115%, method detection levels from 0.5 to 2.7 ng/L, from 0.5 to 2.6 ng/L, and from 0.4 to 11.0 ng/L, and precision from 1 to 19%, from 1 to 16%, and from 1 to 11% in drainage water, river water, and WWTP effluent, respectively. The validated analytical method was applied in investigating the emission of the phytoestrogens via drainage water from a pasture containing 43% red clover ( Trifolium pratense) and in monitoring their occurrence in Swiss surface waters. Isoflavone concentrations ranging from 4 to 157 ng/L and up to 22 ng/L were found in drainage and river water, respectively.  相似文献   

Response of soil microbial communities to the herbicide mesotrione: A dose-effect microcosm approach     

Olivier Crouzet  Isabelle Batisson  Pascale Besse-Hoggan  Frédérique Bonnemoy  Corinne Bardot  Franck Poly  Clarisse Mallet 《Soil biology & biochemistry》2010,42(2):193-1249

Mesotrione is a new selective herbicide used for maize crops. The responses of microbial communities of a chernozem soil (Limagne basin, France) to pure or formulated (Callisto^®) mesotrione, applied at three different doses [one fold field rate (1 × FR), 10 × FR and 100 × FR], were studied using a laboratory microcosm approach. The effects were assessed on the prokaryotic cell abundance, the overall microbial activities (substrate-induced respiration (SIR) and dehydrogenase activity (DHA)) and the genetic structure of the bacterial and fungal communities (temporal temperature/denaturing gradient gel electrophoresis (TT/DGGE)). Mesotrione dissipation was similar whatever the formulation applied and the amounts dissipated were positively correlated to application rates. Several biodegradation products including the metabolites 4-methylsulfonyl-2-nitrobenzoic acid (MNBA) and 2-amino-4-methylsulfonylbenzoic acid (AMBA) were detected from day 42 post-treatment, in 10 × FR and 100 × FR treated soils. No response of the soil microbial communities was detected in soil spread with both the 1 × FR applications. Overall soil microbial activity was stimulated from day 6 by 10 × FR of Callisto^® and more strongly by 100 × FR of pure mesotrione and Callisto^®, whereas prokaryote abundance did not increase before day 95 in both the 100 × FR treatments. Genetic structural shifts recorded from day 42 in the bacterial and fungal communities were small and mainly attributable to variations in band intensity. Maximum dissimilarity of the bacterial and fungal genetic structures between control and 100 × FR treated soils did not exceed 12% and 28%, respectively. The general pattern was that more consistent effects occurred with increasing exposure times, especially in both the 100 × FR treated soils. These microbial responses could be due to the stimulation of (i) adapted mesotrione-degrading microorganisms and (ii) the activity of resistant heterotrophic microbial groups promoted by dead biomass from sensitive organisms. In addition, at 100 × FR doses, pure mesotrione seemed to induce stronger microbial responses than Callisto^®, formulation which contains adjuvants with potential side-effects on some microbial populations. This experimental approach indicated that pure mesotrione and Callisto^® affected soil microbial communities, but the effects were only detected at doses far exceeding the recommended field rates.  相似文献   

Identification of SLEEPLESS, a sleep-promoting factor     

Koh K  Joiner WJ  Wu MN  Yue Z  Smith CJ  Sehgal A 《Science (New York, N.Y.)》2008,321(5887):372-376

Sleep is an essential process conserved from flies to humans. The importance of sleep is underscored by its tight homeostatic control. Through a forward genetic screen, we identified a gene, sleepless, required for sleep in Drosophila. The sleepless gene encodes a brain-enriched, glycosylphosphatidylinositol-anchored protein. Loss of SLEEPLESS protein caused an extreme (>80%) reduction in sleep; a moderate reduction in SLEEPLESS had minimal effects on baseline sleep but markedly reduced the amount of recovery sleep after sleep deprivation. Genetic and molecular analyses revealed that quiver, a mutation that impairs Shaker-dependent potassium current, is an allele of sleepless. Consistent with this finding, Shaker protein levels were reduced in sleepless mutants. We propose that SLEEPLESS is a signaling molecule that connects sleep drive to lowered membrane excitability.  相似文献   

Educational interventions to advance children's scientific thinking     

Klahr D  Zimmerman C  Jirout J 《Science (New York, N.Y.)》2011,333(6045):971-975

The goal of science education interventions is to nurture, enrich, and sustain children's natural and spontaneous interest in scientific knowledge and procedures. We present taxonomy for classifying different types of research on scientific thinking from the perspective of cognitive development and associated attempts to teach science. We summarize the literature on the early--unschooled--development of scientific thinking, and then focus on recent research on how best to teach science to children from preschool to middle school. We summarize some of the current disagreements in the field of science education and offer some suggestions on ways to continue to advance the science of science instruction.  相似文献   

Evidence of excretion of Schmallenberg virus in bull semen     

Claire Ponsart  Nathalie Pozzi  Emmanuel Bréard  Virginie Catinot  Guillaume Viard  Corinne Sailleau  Cyril Viarouge  Julie Gouzil  Martin Beer  Stéphan Zientara  Damien Vitour 《Veterinary research》2014,45(1):37

Schmallenberg virus (SBV) is a novel orthobunyavirus, discovered in Germany in late 2011. It mainly infects cattle, sheep and goats and could lead to congenital infection, causing abortion and fetal abnormalities. SBV is transmitted by biting midges from the Culicoides genus and there is no evidence that natural infection occurs directly between ruminants. Here, we could detect SBV RNA in infected bull semen using qRT-PCR (three bulls out of seven tested positive; 29 positive semen batches out of 136). We also found that highly positive semen batches from SBV infected bulls can provoke an acute infection in IFNAR^-/- mice, suggesting the potential presence of infectious virus in the semen of SBV infected bulls.  相似文献   

Rhizodeposition and net release of soluble organic compounds by pine and beech seedlings inoculated with rhizobacteria and ectomycorrhizal fungi   总被引：3，自引：0，他引：3  

Corinne Leyval  Jacques Berthelin 《Biology and Fertility of Soils》1993,15(4):259-267

Summary A lysimetric experiment was performed in a greenhouse to evalute root deposition and net release of soluble organic compounds after 1 and 2 years from pine and beech seedlings inoculated with an ectomycorrhizal fungus (Laccaria laccata) and/or rhizobacteria (Agrobacterium radiobacter for beech and Agrobacterium sp. for pine). Total C compounds released in the rhizosphere of both plants increased after inoculation with the bacteria or ectomycorrhizal fungus. The rhizobacteria increased root and plant growth and rhizodeposition, but the mycorrhizal fungi appeared to increase only root deposition. Soluble C compounds, collected after 2 years, represented only 0.1–0.3% of the total C compounds released into the rhizosphere, and were modified by inoculation with the microorganisms. After inoculation with the bacteria, levels of sugars and amino acids decreased in pine and beech rhizospheres, whereas organic acids increased, especially in the pine rhizosphere. In the rhizosphere of mycorrhizal beeches, sugar and amino acids increased, and organic acids differed from those released from non-mycorrhizal beeches. In the mycorrhizal pine rhizosphere, however, all compounds decreased. Following dual inoculations, mycorrhizal colonization increased, no effect on plant growth was observed, and virtually no organic acids were detected.  相似文献   

VERTEBRAL BODY HEMANGIOSARCOMA IN A 16-YEAR-OLD MINIATURE SICILIAN DONKEY     

Katherine  Cole Macgillivray  VMD  Corinne R.  Sweeney  DVM  Robert  Mclear  VMD  Perry L.  Habecker  VMD 《Veterinary radiology & ultrasound》2003,44(4):429-432

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Comparison of four pea varieties in pig feeding through digestibility and growth performance results     

Catherine Jondreville  F. Grosjean  G. Buron  Corinne Peyronnet  J. L. Beneytout 《Journal of animal physiology and animal nutrition》1992,68(3):113-122

Vergleich von vier Erbsen-Varietäten für die Ernährung von Schweinen Vier Pisum sativum L.-Varietäten wurden ausgewählt, die große Unterschiede im Gehalt an Antitrypsinfaktoren aufweisen: die Antitrypsinaktivitäten betrugen 2,9; 2,4; 9,7 und 12,8 T.U.I./mg in Solara, H 61, Laser und Frijaune. An vier kastrierten 35 bis 80 kg schweren intakten Schweinen wurde die scheinbare fäkale Energieverdaulichkeit bestimmt, und an drei Kastraten, mit einem Lebendgewicht von 40 bis 60 kg, ausgestattet mit einer termino-terminalen, ileorektalen Anastomose, wurde die scheinbare ileale Protein- und Aminosäurenverdaulichkeit festgestellt. Außerdem wurden die Leistungen von 384 Ferkeln, 8 bis 25 kg Lebendgewicht, bei ad lib. Fütterung mit Rationen, die 40% Solara, H 61, Laser oder Frijaune enthielten, gemessen. Zwischen den scheinbaren Energieverdaulichkeiten der vier Erbsenvarietäten bestand kein signifikanter Unterschied (mittlerer Energiegehalt: 16,8 MJ/kg T.S.). Die ilealen Verdaulichkeiten von Protein und Aminosäuren schienen durch den ADF-Gehalt und die Antitrypsinaktivitäten der Varietäten negativ beeinflußt zu sein. Ferkel, die mit Erbsen gefüttert waren, verbrauchten weniger Futter und hatten eine bessere Futterverwertung als Ferkel der Kontrollgruppe (-2,4; -6,0; und -3,7% für den Verbrauch und 4,0; 7,0; und 6,3% für die Futterverwertung mit Solara, Laser und Frijaune). Die Unterschiede von Protein und Aminosäurenverdaulichkeit erklären teilweise die Unterschiede der Leistung.  相似文献   

Structural biology. Two geometric solutions to a transporting problem     

Smith C 《Science (New York, N.Y.)》2006,311(5758):182-183

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Clinical and histological characterization of hair coat and glandular tissue of Chinese crested dogs     

Dominique J. Wiener  Corinne Gurtner  Lucia Panakova  Theresa‐Bernadette Mausberg  Eliane J. Müller  Cord Drögemüller  Tosso Leeb  Monika M. Welle 《Veterinary dermatology》2013,24(2):274-e62

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