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931.
Luche S Diemer H Tastet C Chevallet M Van Dorsselaer A Leize-Wagner E Rabilloud T 《Proteomics》2004,4(3):551-561
The influence of thiol blocking on the resolution of basic proteins by two-dimensional electrophoresis was investigated. Cysteine blocking greatly increased resolution and decreased streaking, especially in the basic region of the gels. Two strategies for cysteine blocking were found to be efficient: classical alkylation with maleimide derivatives and mixed disulfide exchange with an excess of a low molecular weight disulfide. The effect on resolution was significant enough to allow correct resolution of basic proteins with in-gel rehydration on wide gradients (e.g. 3-10 and 4-12), but anodic cup-loading was still required for basic gradients (e.g. 6-12 or 8-12). These results demonstrate that thiol-related problems are not solely responsible for streaking of basic proteins on two-dimensional gels. 相似文献
932.
Reproduction of Amazon River Dolphins, Inia geoffrensis, is generally reported to be highly seasonal; however, this conclusion is based on studies from only one area of Inia distribution from throughout the Amazon and Orinoco river basins. Our observations of live dolphins from the Orinoco, Amazon, and Mamoré river basins (in Venezuela, Peru and Bolivia, respectively) indicate that reproduction in Inia often occurs year‐round, with seasonal peaks varying according to geographic location. Inia neonates in Peru and Bolivia were seen in all seasons, and were observed most often in falling water (season was defined by relative water level). Conversely, neonates in Venezuela were seen at the end of low water and in rising water, yet were never observed during falling water. Inia mating behavior in Peru was observed in all seasons, while mating was observed only during falling and low water in Bolivia. Our review of the literature from throughout the range of Inia indicates variation in reproductive seasonality, with year‐round reproduction in some areas. Seasonality of peaks in births varied according to study area, and may be more closely associated with local environmental and prey conditions than with taxonomic relatedness, relative seasonal differences in water levels, or broad geographic distribution. 相似文献
933.
934.
Jianbo Wu Chunkai Wang Derek Leas Mireille Vargas Karen L. White David M. Shackleford Gong Chen Austin G. Sanford Ryan M. Hemsley Paul H. Davis Yuxiang Dong Susan A. Charman Jennifer Keiser Jonathan L. Vennerstrom 《Bioorganic & medicinal chemistry letters》2018,28(3):244-248
N,N′-Diaryl ureas have recently emerged as a new antischistosomal chemotype. We now describe physicochemical profiling, in vitro ADME, plasma exposure, and ex vivo and in vivo activities against Schistosoma mansoni for twenty new N,N′-diaryl ureas designed primarily to increase aqueous solubility, but also to maximize structural diversity. Replacement of one of the 4-fluoro-3-trifluoromethylphenyl substructures of lead N,N′-diaryl urea 1 with azaheterocycles and benzoic acids, benzamides, or benzonitriles decreased lipophilicity, and in most cases, increased aqueous solubility. There was no clear relationship between lipophilicity and metabolic stability, although all compounds with 3-trifluoromethyl-4-pyridyl substructures were metabolically stable. N,N′-diaryl ureas containing 4-fluoro-3-trifluoromethylphenyl, 3-trifluoromethyl-4-pyridyl, 2,2-difluorobenzodioxole, or 4-benzonitrile substructures had high activity against ex vivo S. mansoni and relatively low cytotoxicity. N,N-diaryl ureas with 3-trifluoromethyl-4-pyridyl and 2,2-difluorobenzodioxole substructures had the highest exposures whereas those with 4-fluoro-3-trifluoromethylphenyl substructures had the best in vivo antischistosomal activities. There was no direct correlation between compound exposure and in vivo activity. 相似文献
935.
Denisse Sepulveda Diego Rojas-Rivera Diego A. Rodríguez Jody Groenendyk Andres Köhler Cynthia Lebeaupin Shinya Ito Hery Urra Amado Carreras-Sureda Younis Hazari Mireille Vasseur-Cognet Maruf M.U. Ali Eric Chevet Gisela Campos Patricio Godoy Tomas Vaisar Béatrice Bailly-Maitre Kazuhiro Nagata Claudio Hetz 《Molecular cell》2018,69(2):238-252.e7
936.
Myrte Brands Hans P. Sauerwein Mariette T. Ackermans Sander Kersten Mireille J. Serlie 《Journal of lipid research》2013,54(3):615-621
Angiopoietin-like 4 (ANGPTL4) is a regulator of LPL activity. In this study we examined whether different fatty acids have a differential effect on plasma ANGPTL4 levels during hyperinsulinemia in healthy lean males. In 10 healthy lean males, 3 hyperinsulinemic euglycemic clamps were performed during concomitant 6 h intravenous infusion of soybean oil (Intralipid® rich in PUFA), olive oil (Clinoleic® rich in MUFA) and control saline. In 10 other healthy lean males, 2 hyperinsulinemic clamps were performed during infusion of a mixed lipid emulsion containing a mixture of fish oil (FO), medium-chain triglycerides (MCTs), and long-chain triglycerides (LCTs) (FO/MCT/LCT; SMOFlipid®) or saline. FFA levels of approximately 0.5 mmol/l were reached during each lipid infusion. Plasma ANGPTL4 decreased during hyperinsulinemia by 32% (18–52%) from baseline. This insulin-mediated decrease in ANGPTL4 concentrations was partially reduced during concomitant infusion of olive oil and completely blunted during concomitant infusion of soybean oil and FO/MCT/LCT. The reduction in insulin sensitivity was similar between all lipid infusions. In accordance, incubation of rat hepatoma cells with the polyunsaturated fatty acid C22:6 increased ANGPTL4 expression by 70-fold, compared with 27-fold by the polyunsaturated fatty acid C18:2, and 15-fold by the monounsaturated fatty acid C18:1. These results suggest that ANGPTL4 is strongly regulated by fatty acids in humans, and is also dependent on the type of fatty acid. 相似文献
937.
Mireille Andriamihaja Alain Guillot Allan Svendsen Joerg Hagedorn Sahondra Rakotondratohanina Daniel Tomé François Blachier 《Amino acids》2013,44(2):563-572
Utilisation of microbial enzymes may represent an alternative strategy to the use of conventional pancreatin obtained from pig pancreas for the treatment of severe pancreatic insufficiency. In this study, we focused on the capacity of two microbial preparations for their capacity to digest alimentary proteins (caseins and soya proteins) in comparison with pancreatin. These microbial enzymatic preparations were found to be able to generate small, medium-size and larger polypeptides from caseins and soya proteins but were inactivated at pH 3.0. As determined by Liquid Chromatography–Mass Spectrometry analysis, microbial enzymes generated very different peptides from caseins when compared with peptides generated through pancreatin action. These microbial preparations were characterised by relatively low trypsin- and low carboxypeptidase-like activities but high chymotrypsin-like activities and strong capacity for cleavage of caseins at the methionine sites. Although the efficiency of these microbial preparations to increase the rate of absorption of nitrogen-containing compounds in severe pancreatic insufficiency remains to be tested in vivo, our in vitro data indicate proteolytic capacities of such preparations for alimentary protein digestion. 相似文献
938.
Guido Sonnemann Bruce Vigon Mireille Rack Sonia Valdivia 《The International Journal of Life Cycle Assessment》2013,18(5):1169-1172
Purpose
The paper introduces the publication on “Global Guidance Principles for Life Cycle Assessment Databases”; it focuses on the development of training material and other implementation activities on the publication.Methods
The document is the output of the “Shonan Guidance Principles” workshop. The publication provides guidance principles for life cycle assessment (LCA) databases; this includes how to collect raw data, how to develop datasets, and how to manage databases. The publication also addresses questions concerning data documentation and review, coordination among databases, capacity building, and future scenarios. As a next step, the publication is used to prepare training material and other implementation activities.Results
The publication was launched at the LCM 2011 Conference. Since then outreach activities have been organized in particular in emerging economies. Further developments with regard to the guidance principles are foreseen as part of a flagship project within phase 3 of the Life Cycle Initiative. Training material is being developed that will include how to set up databases and develop datasets. The topic has been taken up by United Nations Environment Programme (UNEP) in its Rio?+?20 Voluntary Commitments: UNEP and Society of Environmental Toxicology and Chemistry (SETAC) through the UNEP/SETAC Life Cycle Initiative commit to facilitate improved access to good quality life cycle data and databases as well as expanded use of key environmental indicators that allows the measurement and monitoring of progress towards the environmental sustainability of selected product chains.Conclusions
The adoption of the “Global Guidance Principles” publication as a de facto global standard is expected to facilitate the work of database teams, especially, in developing countries, and the collaboration in regional networks. These efforts are supported by the development of training material and other implementation activities. 相似文献939.
Marjorie Romon Isabelle Soustre-Gacougnolle Carine Schmitt Mireille Perrin Yannick Burdloff Elodie Chevalier Jérome Mutterer Christophe Himber Jér?me Zervudacki Thomas Montavon Aude Zimmermann Taline Elmayan Hervé Vaucheret Patrice Dunoyer Jean E. Masson 《PloS one》2013,8(12)
RNA silencing is a natural defence mechanism against viruses in plants, and transgenes expressing viral RNA-derived sequences were previously shown to confer silencing-based enhanced resistance against the cognate virus in several species. However, RNA silencing was shown to dysfunction at low temperatures in several species, questioning the relevance of this strategy in perennial plants such as grapevines, which are often exposed to low temperatures during the winter season. Here, we show that inverted-repeat (IR) constructs trigger a highly efficient silencing reaction in all somatic tissues in grapevines. Similarly to other plant species, IR-derived siRNAs trigger production of secondary transitive siRNAs. However, and in sharp contrast to other species tested to date where RNA silencing is hindered at low temperature, this process remained active in grapevine cultivated at 4°C. Consistently, siRNA levels remained steady in grapevines cultivated between 26°C and 4°C, whereas they are severely decreased in Arabidopsis grown at 15°C and almost undetectable at 4°C. Altogether, these results demonstrate that RNA silencing operates in grapevine in a conserved manner but is resistant to far lower temperatures than ever described in other species. 相似文献
940.
Mireille Guerrier France Légaré Stéphane Turcotte Michel Labrecque Louis-Paul Rivest 《PloS one》2013,8(4)