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61.
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Gagliardi Federica Lauro Augusto Tripodi Domenico Amabile Maria Ida Palumbo Piergaspare Di Matteo Filippo Maria Palazzini Giorgio Forte Flavio Frattaroli Stefano Khouzam Simone Marino Ignazio R. DAndrea Vito Sorrenti Salvatore Pironi Daniele 《Digestive diseases and sciences》2022,67(3):786-798
Digestive Diseases and Sciences - Mesenteric cysts are defined as a heterogeneous group of intra-abdominal cystic lesions of the mesentery or omentum that may be found in any portion of the... 相似文献
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Irene Paganini Vivian Y Chang Gabriele L Capone Jeremie Vitte Matteo Benelli Lorenzo Barbetti Roberta Sestini Eva Trevisson Theo JM Hulsebos Marco Giovannini Stanley F Nelson Laura Papi 《European journal of human genetics : EJHG》2015,23(7):963-968
Schwannomatosis is characterized by the development of multiple non-vestibular, non-intradermal schwannomas. Constitutional inactivating variants in two genes, SMARCB1 and, very recently, LZTR1, have been reported. We performed exome sequencing of 13 schwannomatosis patients from 11 families without SMARCB1 deleterious variants. We identified four individuals with heterozygous loss-of-function variants in LZTR1. Sequencing of the germline of 60 additional patients identified 18 additional heterozygous variants in LZTR1. We identified LZTR1 variants in 43% and 30% of familial (three of the seven families) and sporadic patients, respectively. In addition, we tested LZTR1 protein immunostaining in 22 tumors from nine unrelated patients with and without LZTR1 deleterious variants. Tumors from individuals with LZTR1 variants lost the protein expression in at least a subset of tumor cells, consistent with a tumor suppressor mechanism. In conclusion, our study demonstrates that molecular analysis of LZTR1 may contribute to the molecular characterization of schwannomatosis patients, in addition to NF2 mutational analysis and the detection of chromosome 22 losses in tumor tissue. It will be especially useful in differentiating schwannomatosis from mosaic Neurofibromatosis type 2 (NF2). However, the role of LZTR1 in the pathogenesis of schwannomatosis needs further elucidation. 相似文献
64.
Gelardi Matteo Ciprandi Giorgio Incorvaia Cristoforo Buttafava Serena Leo Eleonora Iannuzzi Lucia Quaranta Nicola Frati Franco 《Inflammation research》2015,64(6):373-375
Inflammation Research - Allergic rhinitis (AR) is characterized by typical symptoms that are dependent on inflammation. Poly-allergy is a frequent phenomenon. Phenotyping AR represents an... 相似文献
65.
Davide Porrelli Andrea Travan Gianluca Turco Matteo Crosera Massimiliano Borgogna Ivan Donati Sergio Paoletti Gianpiero Adami Eleonora Marsich 《Journal of tissue engineering and regenerative medicine》2018,12(2):e747-e759
Injectable bone fillers represent an attractive strategy for the treatment of bone defects. These injectable materials should be biocompatible, capable of supporting cell growth and possibly able to exert antibacterial effects. In this work, nanocomposite microbeads based on alginate, chitlac, hydroxyapatite and silver nanoparticles were prepared and characterized. The dried microbeads displayed a rapid swelling in contact with simulated body fluid and maintained their integrity for more than 30 days. The evaluation of silver leakage from the microbeads showed that the antibacterial metal is slowly released in saline solution, with less than 6% of silver released after 1 week. Antibacterial tests proved that the microbeads displayed bactericidal effects toward Staphylococcus aureus, Pseudomonas aeruginosa and Staphylococcus epidermidis, and were also able to damage pre‐formed bacterial biofilms. On the other hand, the microbeads did not exert any cytotoxic effect towards osteoblast‐like cells. After characterization of the microbeads bioactivity, a possible means to embed them in a fluid medium was explored in order to obtain an injectable paste. Upon suspension of the particles in alginate solution or alginate/hyaluronic acid mixtures, a homogenous and time‐stable paste was obtained. Mechanical tests enabled to quantify the extrusion forces from surgical syringes, pointing out the proper injectability of the material. This novel antibacterial bone filler appears as a promising material for the treatment of bone defects, in particular when possible infections could compromise the bone‐healing process. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Jian Liu Chia-Yun Lai Yu-Yang Zhang Matteo Chiesa Sokrates T. Pantelides 《RSC advances》2018,8(30):16918
Wetting phenomena are ubiquitous and impact a wide range of applications. Simulations so far have largely relied on classical potentials. Here, we report the development of an approach that combines density-functional theory (DFT)-based calculations with classical wetting theory that allows practical but sufficiently accurate determination of the water contact angle (WCA). As a benchmark, we apply the approach to the graphene and graphite surfaces that recently received considerable attention. The results agree with and elucidate the experimental data. For metal-supported graphene where electronic interactions play a major role, we demonstrate that doping of graphene by the metal substrate significantly alters the wettability. In addition to theory, we report new experimental measurements of the WCA and the force of adhesion that corroborate the theoretical results. We demonstrate a correlation between the force of adhesion and WCA, and the use of the atomic force microscope (AFM) technique as an alternative measure for wettability at the nanoscale. The present work not only provides a detailed understanding of the wettability of graphene, including the role of electrons, but also sets the stage for studying the wettability alteration mechanism when sufficiently accurate force fields may not be available.Wettability of graphene is characterized from first principles.Wetting phenomena are ubiquitous in a variety of practical issues, including adhesion,1 friction,2 interfacial thermal conductance (Kapitza conductance),3,4 to name just a few. Graphene has emerged as an important material for applications where water wettability plays a major role, e.g., as a lubricant,5 small-molecule gas sensor,6,7 desalination membrane,8,9 protective coating from electrochemical degradation,10 promotive coating for dropwise condensation,11etc. Among these applications, to wet or not to wet is the key problem.12,13 More recently, doping-induced tunable wettability was reported for graphene.14,15Interactions between the wetting liquid and the solid it rests on are responsible for the wetting properties of a surface. The binding energy of individual molecules on the solid surface, obtained by quantum-mechanical calculations, has at times been used as an indicator of wettability.14,16 A better indicator, however, is the water contact angle (WCA), an experimentally easily accessible parameter that characterizes macroscopically a surface''s wettability by water.17,18 Large WCA, >90°, signifies hydrophobic behavior, whereas small WCA, <90°, signifies hydrophilic behavior. The past few years have witnessed increasing efforts to understand the wetting mechanism of graphitic carbon surfaces. Theoretical calculations of WCAs of graphitic carbon surfaces have so far been done primarily using classical potentials, by constructing an analytical interaction potential between water and the solid surface based on interatomic Lennard-Jones potentials19–21 or classical molecular dynamics (CMD) simulations.19,22–29 In those pioneering studies with the work-of-adhesion approach, one first computes the work of adhesion of a water slab on a surface and then employs the Young-Dupré equation that relates the work of adhesion to the WCA.19,25–28 Alternatively, CMD can be sued to measures the shape of a water droplet on a surface and extract the WCA.22–24Though these approaches have provided significant insights into wetting behavior,19,22–28 they depend on the availability of reliable classical potentials. The construction of such potentials becomes a difficult task when many atomic species are present. For example, the interplay between ions such as Ca2+, Mg2+, SO42−, Na+ and Cl− in saline water and calcite (CaCO3) surfaces is responsible for the wettability alteration for oil recovery.30,31 There are also cases, e.g., monolayers on metallic substrates, where explicit electron doping effects may play a major role, requiring electronic-structure calculations. While density functional theory (DFT) is the method of choice for predictive, atomic-scale calculations of interactions at the solid–water interface, the major difficulty lies in the limited time and length scales achievable by quantum MD (QMD) simulations.32 So far there exists only one report of QMD simulations of water nanodroplets, on graphene and hexagonal boron nitride monolayers.33In this paper, we adopt the method based on the work of adhesion and the Young-Dupré equation, and employ an approximation that allows practical but sufficiently accurate DFT-based determination of the WCA. Benchmark calculations confirm that graphitic carbon surfaces are nonpolar and intrinsically hydrophilic, with their wettability determined by the dispersive interaction. The WCA gradually decreases with increasing number of graphene layers N, while a monolayer of adsorbed hydrocarbons is sufficient to render graphene hydrophobic, complementing similar results obtained using classical potentials.20,21,25,34 In the presence of a metal substrate, electronic structure comes into play and electron doping of the graphene sheet by the metal substrate alters the wettability of graphene. We report new WCA and AFM (atomic force microscopy) measurements for Cu-supported monolayer and multilayer graphene that further corroborate the theoretical results. Finally, we demonstrate a correlation between the force of adhesion and WCA, and the use of the AFM technique as an alternative measure for wettability at the nanoscopic scale. 相似文献
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Borchiellini Alessandra Castaman Giancarlo Feola Giulio Ferretti Antonietta Giordano Paola Luciani Matteo Malcangi Giuseppe Margaglione Maurizio Molinari Angelo Claudio Pollio Berardino Rocino Angiola Santoro Cristina Schiavulli Michele Zanon Ezio 《Journal of thrombosis and thrombolysis》2022,53(4):934-944
Journal of Thrombosis and Thrombolysis - rVIII-SingleChain is indicated for treatment and prophylaxis of bleeding in patients with haemophilia A (HA). The safety and efficacy of rVIII-SingleChain... 相似文献