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排序方式: 共有2455条查询结果,搜索用时 31 毫秒
81.
Alain Doyen Linda Saucier Lucie Beaulieu Yves Pouliot Laurent Bazinet 《Food chemistry》2012,132(3):1177-1184
Recently, a snow crab by-products hydrolysate has demonstrated antibacterial properties due to a peptide with a molecular weight of about 800 Da, but only at high concentration. Consequently, peptide hydrolysate has been fractionated to obtain peptides in a more purified form. The aim of this work was to separate a snow crab by-products hydrolysate by electrodialysis with ultrafiltration membranes (EDUF). EDUF, which allows separation of molecules according to their charges and molecular weights, was used to recover and concentrate the active antibacterial fraction. Two different ultrafiltration membranes (20 and 50 kDa) and two electrical field strengths (2 and 14 V/cm) were used as separation parameters. After EDUF separation, the 300-600 Da peptide molecular weight range was the most recovered with an abundance of 94%. Moreover, fractionation at 14 V/cm with ultrafiltration membranes of 50 kDa allowed the recovery of an anionic fraction which showed antibacterial properties on Escherichia coli ATCC 25922 and Listeria innocua HPB 13. 相似文献
82.
Shankumar Mooyottu Anup Kollanoor-Johny Genevieve Flock Laurent Bouillaut Abhinav Upadhyay Abraham L. Sonenshein Kumar Venkitanarayanan 《International journal of molecular sciences》2014,15(3):4415-4430
Clostridium difficile is a nosocomial pathogen that causes a serious toxin-mediated enteric disease in humans. Reducing C. difficile toxin production could significantly minimize its pathogenicity and improve disease outcomes in humans. This study investigated the efficacy of two, food-grade, plant-derived compounds, namely trans-cinnamaldehyde (TC) and carvacrol (CR) in reducing C. difficile toxin production and cytotoxicity in vitro. Three hypervirulent C. difficile isolates were grown with or without the sub-inhibitory concentrations of TC or CR, and the culture supernatant and the bacterial pellet were collected for total toxin quantitation, Vero cell cytotoxicity assay and RT-qPCR analysis of toxin-encoding genes. The effect of CR and TC on a codY mutant and wild type C. difficile was also investigated. Carvacrol and TC substantially reduced C. difficile toxin production and cytotoxicity on Vero cells. The plant compounds also significantly down-regulated toxin production genes. Carvacrol and TC did not inhibit toxin production in the codY mutant of C. difficile, suggesting a potential codY-mediated anti-toxigenic mechanism of the plant compounds. The antitoxigenic concentrations of CR and TC did not inhibit the growth of beneficial gut bacteria. Our results suggest that CR and TC could potentially be used to control C. difficile, and warrant future studies in vivo. 相似文献
83.
Laurent Ponson Walid Arkouche Maurice Laville 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):7-14
Hemodialysis is one of the most water and energy‐hungry medical procedures, and thus represents a clear opportunity where improvements should be made concerning the consumption and wastage of water. Three levels were investigated on which there are potential savings: the precise adjustment of water production according to specific needs, the reuse of reverse osmosis rejected water, and finally the huge volumes of post‐patient dialysate effluent. The “AURAL” (Association pour l′Utilisation du Rein Artificiel à Lyon), main unit in Lyon, was the site of investigation for this study, which cares for 173 chronic hemodialysis patients. Evaluation of the 3 levels described earlier was undertaken on this particular building, and on the water treatment currently used. Volumes of produced water can be improved by different hydraulic systems or by adjusting the pure water conductivity used for dialysis. Concerning the reject water, reuse for building sanitation became the focus of further attention. The technical feasibility, volume of saved water, and applicable work costs were considered. The results suggest that out of a possible 2834 m3/year of reject water, 1200 m3/year may be reused and return on investment recovered within 5.8 years. Finally, the reprocessing and feasibility of reuse of dialysate effluent were investigated. Initial calculations show that although technical solutions are available, such processing of the wastewater production is not profitable in the short term. Regarding the significant prior authorization and risk management analysis necessary for such a project, this avenue was pursued no further. From the perspective of a “green dialysis,” the reuse of reject water into sanitation is both viable and profitable in our unit, and must be the next step of our project. More widely, improvements can be made by defining a more precise range of pure water conductivity for dialysis and by applying reuse water project to new or to be renovated units. 相似文献
84.
Isabelle Marie-Joseph Laurent Linguet Marie-Line Gobinddass 《International journal of remote sensing》2013,34(8):3012-3027
Measurements of daily means of surface solar irradiance made at four ground stations in French Guiana are compared to estimates from the HelioClim-3 database produced by the Heliosat-2 method applied to Meteosat satellite images. The bias ranges from 12 W m?2 (6% of the mean of measurements) to 23 W m?2 (12%), depending on the stations. The root mean square difference ranges between 23 W m?2 (11%) and 35 W m?2 (18%). The correlation coefficient (r) is close to 0.9. Better results are observed during the rainy season than during the dry season. Uncertainties are mainly due to the presence of clouds, large viewing angles of the Meteosat satellite, and limitations of the atmospheric transmittance model under the tropical atmospheric conditions. It is concluded that the Heliosat-2 method provides new knowledge about solar radiation in French Guiana. 相似文献
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87.
Chatterjee Gaurav Latorre Laurent Mailly Frédérick Nouet Pascal Hachelef Nacim Oudea Coumar 《Microsystem Technologies》2017,23(9):3969-3978
Microsystem Technologies - Inertial measurement units (IMU) are essentially a combination of acceleration and rotation rate sensors, generating position and attitude information. For tactical and... 相似文献
88.
Hallal Nassim Yelles Chaouche Abdelkrim Hamai Lamine Lamali Atmane Dubois Laurent Mohammedi Yahia Hamidatou Mouloud Djadia Leila Abtout Abdeslam 《Bulletin of Engineering Geology and the Environment》2019,78(8):5653-5670
Bulletin of Engineering Geology and the Environment - A better understanding of the spatiotemporal evolution of landslides in urban zones is a key factor in assessing the risk of future slides... 相似文献
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90.
Discovery of Heterocyclic Nonacetamide Synaptic Vesicle Protein 2A (SV2A) Ligands with Single‐Digit Nanomolar Potency: Opening Avenues towards the First SV2A Positron Emission Tomography (PET) Ligands 下载免费PDF全文
Joël Mercier Laurence Archen Véronique Bollu Stéphane Carré Yves Evrard Dr. Eric Jnoff Dr. Benoît Kenda Bénédicte Lallemand Dr. Philippe Michel Dr. Florian Montel Dr. Florence Moureau Nathalie Price Dr. Yannick Quesnel Dr. Xavier Sauvage Dr. Anne Valade Dr. Laurent Provins 《ChemMedChem》2014,9(4):693-698
The role of the synaptic vesicle protein 2A (SV2A) protein, target of the antiepileptic drug levetiracetam, is still mostly unknown. Considering its potential to provide in vivo functional insights into the role of SV2A in epileptic patients, the development of an SV2A positron emission tomography (PET) tracer has been undertaken. Using a 3D pharmacophore model based on close analogues of levetiracetam, we report the rationale design of three heterocyclic non‐acetamide lead compounds, UCB‐A, UCB‐H and UCB‐J, the first single‐digit nanomolar SV2A ligands with suitable properties for development as PET tracers. 相似文献