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21.
Organ Repair,Hemostasis, and In Vivo Bonding of Medical Devices by Aqueous Solutions of Nanoparticles 下载免费PDF全文
Prof. Dr. Anne Meddahi‐Pellé Aurélie Legrand Dr. Alba Marcellan Liliane Louedec Prof. Dr. Didier Letourneur Prof. Dr. Ludwik Leibler 《Angewandte Chemie (International ed. in English)》2014,53(25):6369-6373
Sutures are traumatic to soft connective tissues, such as liver or lungs. Polymer tissue adhesives require complex in vivo control of polymerization or cross‐linking reactions and currently suffer from being toxic, weak, or inefficient within the wet conditions of the body. Herein, we demonstrate using Stöber silica or iron oxide nanoparticles that nanobridging, that is, adhesion by aqueous nanoparticle solutions, can be used in vivo in rats to achieve rapid and strong closure and healing of deep wounds in skin and liver. Nanoparticles were also used to fix polymer membranes to tissues even in the presence of blood flow, such as occurring after liver resection, yielding permanent hemostasis within a minute. Furthermore, medical devices and tissue engineering constructs were fixed to organs such as a beating heart. The simplicity, rapidity, and robustness of nanobridging bode well for clinical applications, surgery, and regenerative medicine. 相似文献
22.
Frontispiece: NMR Fingerprints of the Drug‐like Natural‐Product Space Identify Iotrochotazine A: A Chemical Probe to Study Parkinson’s Disease 下载免费PDF全文
23.
Beatriz Lozano‐Torres Juan F. Blandez Irene Galiana Alba García‐Fernndez María Alfonso María D. Marcos Mar Orzez Flix Sancenn Ramn Martínez‐Mez 《Angewandte Chemie (International ed. in English)》2020,59(35):15152-15156
In vivo detection of cellular senescence is accomplished by using mesoporous silica nanoparticles loaded with the NIR‐FDA approved Nile blue (NB) dye and capped with a galactohexasaccharide ( S3 ). NB emission at 672 nm is highly quenched inside S3 , yet a remarkable emission enhancement is observed upon cap hydrolysis in the presence of β‐galactosidase and dye release. The efficacy of the probe to detect cellular senescence is tested in vitro in melanoma SK‐Mel‐103 and breast cancer 4T1 cells and in vivo in palbociclib‐treated BALB/cByJ mice bearing breast cancer tumor. 相似文献
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Alex ZeaAndrea-Nekane R. Alba Natalia BravoAlbert Moyano Ramon Rios 《Tetrahedron》2011,67(14):2513-2529
Asymmetric organocatalytic additions of anthrones to activated alkenes are discussed. The reaction between anthrone or dithranol and α,β-unsaturated aldehydes is catalyzed by diphenylprolinol trimethylsilyl ether in toluene at −40 °C, giving the Michael adducts with good yields and enantioselectivities. Bifunctional amino-thioureas efficiently catalyze the additions of anthrones to both nitroalkenes and maleimides, and high enantioselectivities can be achieved in both instances at room temperature. In the case of nitroalkenes, a Michael addition takes exclusively place. Anthrone generally gives Diels-Alder cycloadducts in the reaction with maleimides, while dithranol affords the Michael adducts. Transition state working models in which the bifunctional catalyst binds simultaneously to the alkene and to the anthrone enolate account for the stereochemical outcome of these additions. 相似文献
27.
In this paper we study a family of stochastic orders of random variables defined via the comparison of their percentile residual life functions. Some interpretations of these stochastic orders are given, and various properties of them are derived. The relationships to other stochastic orders are also studied. Finally, some applications in reliability theory and finance are described. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
28.
Lacaze E. Alba M. Goldmann M. Michel J. P. Rieutord F. 《The European Physical Journal B - Condensed Matter and Complex Systems》2004,39(2):261-272
By combining X-ray diffraction under grazing incidence (GIXD) and scanning tunneling microscopy (STM) measurements, we have determined the structure of 4-n-octyl-4-cyanobiphenyl (8CB) molecules adsorbed on MoS2, under the thick organic film. The commensurability of the adsorbed network and the unit cell structure have been determined, revealing a complex 2D structure. This structure is characterized by straight ribbons with two types of ribbons, alternatively stacked. In one type, molecules are equally spaced, as they are paired in the other type. Considering the energetics of adsorption with a model of single ribbon, we recover the two observed ribbon structures. The alternate stacking of the ribbons appears as a consequence of the connection between the commensurabilities in the two main crystallographic directions. Moreover, we have found a particularly high value for the molecule-substrate potential corrugations, indicating that the dipole moment of 8CB molecules could play a fundamental role in the molecule-substrate interactions.Received: 1 April 2004, Published online: 29 June 2004PACS:
61.10.-i X-ray diffraction and scattering - 68.35.Bs Structure of clean surfaces (reconstruction) - 61.30.-v Liquid crystals - 68.35.Md Surface thermodynamics, surface energies 相似文献
29.
Antonella Cristiano Alba Marcellan Bert J. Keestra Paul Steeman Costantino Creton 《Journal of Polymer Science.Polymer Physics》2011,49(5):355-367
Fracture properties of model elastomeric networks of polyurethane have been investigated with a double‐edge notch geometry. The networks were synthesized from monodisperse end‐functionalized polypropylene glycol precursors and a trifunctional isocyanate. All reagents were carefully purified and nearly defect‐free ideal networks were prepared at a stoichiometry very close to the theoretical one. Three networks were prepared: an unentangled network of short chains (Mn = 4 kg mol?1), an entangled network of longer chains (Mn = 8 kg mol?1) and a bimodal network with 8 kg mol?1 and 1 kg mol?1 chains. The presence of entanglements was found to increase significantly the toughness of the rubber, in particular at room temperature, relative to the bimodal networks and to the short chains network. Fracture experiments were carried out at different strain rates and temperatures and showed for all three networks a marked decrease in fracture toughness with increasing temperature and decreasing strain rate which mirrored reasonably well the rate and temperature dependence of tan δ, the dissipative factor. However the proportionality factor between tan δ, and GIC was very material dependent and the shift factors obtained for the master curves of the viscoelastic properties could not be used to build fracture energy master curves. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010 相似文献
30.
Brandon J. O'Neill David H. K. Jackson Dr. Anthony J. Crisci Carrie A. Farberow Fengyuan Shi Dr. Ana C. Alba‐Rubio Dr. Junling Lu Dr. Paul J. Dietrich Dr. Xiangkui Gu Dr. Christopher L. Marshall Prof. Peter C. Stair Dr. Jeffrey W. Elam Dr. Jeffrey T. Miller Prof. Fabio H. Ribeiro Prof. Paul M. Voyles Prof. Jeffrey Greeley Prof. Manos Mavrikakis Prof. Susannah L. Scott Prof. Thomas F. Kuech Prof. James A. Dumesic 《Angewandte Chemie (International ed. in English)》2013,52(51):13824-13824