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81.
Design and Synthesis of Galactosylated Bifurcated Ligands with Nanomolar Affinity for Lectin LecA from Pseudomonas aeruginosa 下载免费PDF全文
Dr. Anthony Angeli Muchen Li Dr. Lucie Dupin Dr. Gérard Vergoten Mathieu Noël Mimouna Madaoui Dr. Shuai Wang Albert Meyer Thomas Géhin Dr. Sébastien Vidal Dr. Jean‐Jacques Vasseur Dr. Yann Chevolot Dr. François Morvan 《Chembiochem : a European journal of chemical biology》2017,18(11):1036-1047
Lectin A (LecA) from Pseudomonas aeruginosa is an established virulence factor. Glycoclusters that target LecA and are able to compete with human glycoconjugates present on epithelial cells are promising candidates to treat P. aeruginosa infection. A family of 32 glycodendrimers of generation 0 and 1 based on a bifurcated bis‐galactoside motif have been designed to interact with LecA. The influences both of the central multivalent core and of the aglycon of these glycodendrimers on their affinity toward LecA have been evaluated by use of a microarray technique, both qualitatively for rapid screening of the binding properties and also quantitatively (Kd). This has led to high‐affinity LecA ligands with Kd values in the low nanomolar range (Kd=22 nm for the best one). 相似文献
82.
我国大城市中普通老房子变得十分稀有。对照西方发达国家以丰富遗产内容为手段并获得类似问题的多样性解决的经验,针对我国相关保护法规缺失的现实情况,通过详细的现场踏勘调查,对成都市区残存老房子面临的问题进行了梳理;针对认识上的缺位,从历史和文化的角度分析了普通老房子的遗产价值并从技术层面提出了维护利用方法。据此,建议应该及时建立科学的遗产甄别体系,为保持和塑造城市特色留下希望的“火种”。 相似文献
83.
84.
In this paper,we presented a novel strategy to employ a plantderived carbohydrate polymer,i.e.,cellulose,to prepare a hydrophobic composite.Cellulose was used as a scaffold,and ethylene-propylene side by side(ES)fiber was thermally melted and then coated on the cellulose surface to achieve hydrophobicity.Experimental results revealed that the thermocoating ES fibers greatly increased the water contact angle of the cellulose scaffold from 25°to 153°while simultaneously enhanced the wet tensile strength of the composite approximately 6.7-fold(drying temperature of 170℃)compared with the pure cellulose paper.In particular,compared with other related research,the prepared cellulose-based composite possessed excellent hydrophobicity and superior mechanical strength,which introduces a new chemical engineering approach to prepare hydrophobic cellulose-based functional materials. 相似文献
85.
Yann Champenois M A Rao Larry P Walker 《Journal of the science of food and agriculture》1998,78(1):119-126
Viscoelastic properties of dispersions (60–300 g kg−1) of gluten (G) and wheat starch (S) blends (0 < G/S < 0·20) and wheat flour have been studied during heating and cooling. In both cases, the moduli followed power law relationships with concentration. The temperature at which the transient network development began, caused by granule–granule interactions, decreased as the concentration increased and increased with an increase in the proportion of gluten. Moreover, gluten weakened the strength of both starch pastes and gels, as shown by the lower values of the moduli. The viscoelastic behaviour of flour samples reflected the role played by internal lipids. A structural model is proposed in order to explain the influence of gluten on the rheological behaviour of starch pastes and gels. © 1998 Society of Chemical Industry. 相似文献
86.
Eliel González‐García Yann Alexandrine Tatiana Silou‐Etienne Harry Archimède 《Journal of the science of food and agriculture》2009,89(11):1918-1926
BACKGROUND: The in situ technique (IS) is used for characterising, screening and evaluating feedstuffs in ruminants. However, it is often not adapted to the particular characteristics of feeds (i.e. kinetics of starchy feeds with a standard framework used in forage). This may lead to potential biases in the final conclusions. In two successive experiments, we evaluated the degradative characteristics of conventional (CON) and unconventional (UNC) starchy feedstuffs (ING) and factors affecting their washable fractions (WF). The suitability of IS was then assessed. RESULTS: Two well‐defined ruminal fermentation patterns (CON and UNC) were observed. The WF and insoluble washable (ISWF) fractions were affected by ING, state of presentation [WAY, fresh (F) or pre‐dried (D)], particle size (PSI) and their interactions. The UNC and F feeds had greater WF and ISWF than CON and D, respectively. Increasing PSI linearly reduced WF and its proportion of ISWF. CONCLUSION: The PSI and WAY are critical factors to consider when designing experiments for the evaluation of starchy feedstuffs for ruminants using IS. It is still very risky to propose ‘standard’ parameters as this will always depend on the particular ING evaluated. Conducting pre‐evaluation tests before implementing each research protocol could help to refine the procedure. Copyright © 2009 Society of Chemical Industry 相似文献
87.
Yann Sarazin Pierre de Frmont Liana Annunziata Michel Duc Jean‐Franois Carpentier 《Advanced Synthesis \u0026amp; Catalysis》2011,353(8):1367-1374
Combinations of the discrete neutral allyl ansa‐lanthanidocenes {Me2C(Cp)(Flu)}Nd[1,3‐ (SiMe3)2C3H3] and rac‐{Me2C(Ind)2}Y[1,3‐ (SiMe3)2C3H3] with di(n‐butyl)magnesium constitute efficient binary catalytic systems for the stereocontrolled coordinative chain transfer polymerization of styrene, yielding near‐perfect syndio‐ and isospecific polystyrenes, respectively, with high activities and productivities. By adjusting the amount of di(n‐butyl)magnesium, up to 200 polymer chains can be generated per lanthabide center, and good control of the molecular weight features enables the tailoring of low to medium molecular weight polymers. 相似文献
88.
The growth of carbon nanotubes from Ni catalysts is reversed and observed in real time in a transmission electron microscope, at room temperature. The Ni catalyst is found to be Ni3C and remains attached to the nanotube throughout the irradiation sequence, indicating that C most likely diffuses on the surface of the catalyst to form nanotubes. We calculate the energy barrier for saturating the Ni3C (2-13) surface with C to be 0.14 eV, thus providing a low-energy surface for the formation of graphene planes. 相似文献
89.
Influence of strontium for calcium substitution in bioactive glasses on degradation,ion release and apatite formation 总被引:1,自引:0,他引:1
Yann C. Fredholm Natalia Karpukhina Delia S. Brauer Julian R. Jones Robert V. Law Robert G. Hill 《Journal of the Royal Society Interface》2012,9(70):880-889
Bioactive glasses are able to bond to bone through the formation of hydroxy-carbonate apatite in body fluids while strontium (Sr)-releasing bioactive glasses are of interest for patients suffering from osteoporosis, as Sr was shown to increase bone formation both in vitro and in vivo. A melt-derived glass series (SiO2–P2O5–CaO–Na2O) with 0–100% of calcium (Ca) replaced by Sr on a molar base was prepared. pH change, ion release and apatite formation during immersion of glass powder in simulated body fluid and Tris buffer at 37°C over up to 8 h were investigated and showed that substituting Sr for Ca increased glass dissolution and ion release, an effect owing to an expansion of the glass network caused by the larger ionic radius of Sr ions compared with Ca. Sr release increased linearly with Sr substitution, and apatite formation was enhanced significantly in the fully Sr-substituted glass, which allowed for enhanced osteoblast attachment as well as proliferation and control of osteoblast and osteoclast activity as shown previously. Studying the composition–structure–property relationship in bioactive glasses enables us to successfully design next-generation biomaterials that combine the bone regenerative properties of bioactive glasses with the release of therapeutically active Sr ions. 相似文献
90.
Matthieu DubarryCyril Truchot Mikaël CugnetBor Yann Liaw Kevin GeringSergiy Sazhin David JamisonChristopher Michelbacher 《Journal of power sources》2011,196(23):10328-10335
Evaluating commercial Li-ion batteries presents some unique benefits. One of them is to use cells made from established fabrication process and form factor, such as those offered by the 18650 cylindrical configuration, to provide a common platform to investigate and understand performance deficiency and aging mechanism of target chemistry. Such an approach shall afford us to derive relevant information without influence from processing or form factor variability that may skew our understanding on cell-level issues. A series of 1.9 Ah 18650 lithium ion cells developed by a commercial source using a composite positive electrode comprising {LiMn1/3Ni1/3Co1/3O2 + LiMn2O4} is being used as a platform for the investigation of certain key issues, particularly path-dependent aging and degradation in future plug-in hybrid electric vehicle (PHEV) applications, under the US Department of Energy's Applied Battery Research (ABR) program. Here we report in Part I the initial characterizations of the cell performance and Part II some aspects of cell degradation in 2C cycle aging. The initial characterizations, including cell-to-cell variability, are essential for life cycle performance characterization in the second part of the report when cell-aging phenomena are discussed. Due to the composite nature of the positive electrode, the features (or signature) derived from the incremental capacity (IC) of the cell appear rather complex. In this work, the method to index the observed IC peaks is discussed. Being able to index the IC signature in details is critical for analyzing and identifying degradation mechanism later in the cycle aging study. 相似文献