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排序方式: 共有418条查询结果,搜索用时 31 毫秒
61.
Elisabetta Coppi Ilaria Dettori Federica Cherchi Irene Bulli Martina Venturini Daniele Lana Maria Grazia Giovannini Felicita Pedata Anna Maria Pugliese 《International journal of molecular sciences》2020,21(24)
Adenosine is a signaling molecule, which, by activating its receptors, acts as an important player after cerebral ischemia. Here, we review data in the literature describing A2BR-mediated effects in models of cerebral ischemia obtained in vivo by the occlusion of the middle cerebral artery (MCAo) or in vitro by oxygen-glucose deprivation (OGD) in hippocampal slices. Adenosine plays an apparently contradictory role in this receptor subtype depending on whether it is activated on neuro-glial cells or peripheral blood vessels and/or inflammatory cells after ischemia. Indeed, A2BRs participate in the early glutamate-mediated excitotoxicity responsible for neuronal and synaptic loss in the CA1 hippocampus. On the contrary, later after ischemia, the same receptors have a protective role in tissue damage and functional impairments, reducing inflammatory cell infiltration and neuroinflammation by central and/or peripheral mechanisms. Of note, demyelination following brain ischemia, or autoimmune neuroinflammatory reactions, are also profoundly affected by A2BRs since they are expressed by oligodendroglia where their activation inhibits cell maturation and expression of myelin-related proteins. In conclusion, data in the literature indicate the A2BRs as putative therapeutic targets for the still unmet treatment of stroke or demyelinating diseases. 相似文献
62.
Francesco Morena Chiara Argentati Michelina Soccio Ilaria Bicchi Francesca Luzi Luigi Torre Andrea Munari Carla Emiliani Matteo Gigli Nadia Lotti Ilaria Armentano Sabata Martino 《International journal of molecular sciences》2020,21(23)
Herein, we present poly(butylene 1,4-cyclohexanedicarboxylate) (PBCE) films characterized by an unpatterned microstructure and a specific hydrophobicity, capable of boosting a drastic cytoskeleton architecture remodeling, culminating with the neuronal-like differentiation of human bone marrow-mesenchymal stem cells (hBM-MSCs). We have used two different filming procedures to prepare the films, solvent casting (PBCE) and compression-moulding (PBCE*). PBCE film had a rough and porous surface with spherulite-like aggregations (Ø = 10–20 μm) and was characterized by a water contact angle = 100°. PBCE* showed a smooth and continuous surface without voids and visible spherulite-like aggregations and was more hydrophobic (WCA = 110°). Both surface characteristics were modulated through the copolymerization of different amounts of ether-oxygen-containing co-units into PBCE chemical structure. We showed that only the surface characteristics of PBCE-solvent-casted films steered hBM-MSCs toward a neuronal-like differentiation. hBM-MSCs lost their canonical mesenchymal morphology, acquired a neuronal polarized shape with a long cell protrusion (≥150 μm), expressed neuron-specific class III β-tubulin and microtubule-associated protein 2 neuronal markers, while nestin, a marker of uncommitted stem cells, was drastically silenced. These events were observed as early as 2-days after cell seeding. Of note, the phenomenon was totally absent on PBCE* film, as hBM-MSCs maintained the mesenchymal shape and behavior and did not express neuronal/glial markers. 相似文献
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64.
Miriam Saponaro Isabella Giacomini Giulia Morandin Veronica Cocetta Eugenio Ragazzi Genny Orso Ilaria Carnevali Massimiliano Berretta Mariangela Mancini Francesco Pagano Monica Montopoli 《International journal of molecular sciences》2020,21(23)
Benign prostatic hyperplasia (BPH) is an age-related chronic disorder, characterized by the hyperproliferation of prostatic epithelial and stromal cells, which drives prostate enlargement. Since BPH aetiology and progression have been associated with the persistence of an inflammatory stimulus, induced both by Nuclear Factor-kappa B (NF-κB) activation and reactive oxygen species (ROS) production, the inhibition of these pathways could result in a good tool for its clinical treatment. This study aimed to evaluate the antioxidant and anti-inflammatory activity of a combined formulation of Serenoa repens and Urtica dioica (SR/UD) in an in vitro human model of BPH. The results confirmed both the antioxidant and the anti-inflammatory effects of SR/UD. In fact, SR/UD simultaneously reduced ROS production, NF-κB translocation inside the nucleus, and, consequently, interleukin 6 (IL-6) and interleukin 8 (IL-8) production. Furthermore, the effect of SR/UD was also tested in a human androgen-independent prostate cell model, PC3. SR/UD did not show any significant antioxidant and anti-inflammatory effect, but was able to reduce NF-κB translocation. Taken together, these results suggested a promising role of SR/UD in BPH and BPH-linked disorder prevention. 相似文献
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66.
Fluorescent Diarylethene Photoswitches—A Universal Tool for Super‐Resolution Microscopy in Nanostructured Materials 下载免费PDF全文
Oleksii Nevskyi Dmytro Sysoiev Jes Dreier Simon Christoph Stein Alex Oppermann Florian Lemken Tobias Janke Jörg Enderlein Ilaria Testa Thomas Huhn Dominik Wöll 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(10)
Super‐resolution fluorescence microscopy allows for unprecedented in situ visualization of biological structures, but its application to materials science has so far been comparatively limited. One of the main reasons is the lack of powerful dyes that allow for labeling and photoswitching in materials science systems. In this study it is shown that appropriate substitution of diarylethenes bearing a fluorescent closed and dark open form paves the way for imaging nanostructured materials with three of the most popular super‐resolution fluorescence microscopy methods that are based on different concepts to achieve imaging beyond the diffraction limit of light. The key to obtain optimal resolution lies in a proper control over the photochemistry of the photoswitches and its adaption to the system to be imaged. It is hoped that the present work will provide researchers with a guide to choose the best photoswitch derivative for super‐resolution microscopy in materials science, just like the correct choice of a Swiss Army Knife's tool is essential to fulfill a given task. 相似文献
67.
Francesco Piana Ilaria Cacciotti Miroslav Šlouf Francesca Nanni Jiří Pfleger 《Journal of Materials Science》2018,53(16):11343-11354
An advanced and inexpensive one-pot method to prepare polystyrene (PS)–barium titanate (BT) films by solution mixing is reported. The process was developed to obtain free-standing films with an increased dielectric constant (ε′). Since PS is soluble in apolar solvents, BT nanoparticles (BT-NPs) were surface-modified with palmitic acid (PAc) and embedded within the polymer matrix without affecting homogeneity and smoothness of the composite. The films were prepared by floating method consisting in dropping BT-NPs dispersed in PS/toluene solution on the water surface. After the evaporation of toluene, smooth, free-standing and thermally stable films were obtained with a markedly higher ε′ compared to the neat PS. PAc modification improved the dispersion of BT-NPs in the apolar phase and prevented their diffusion into the aqueous phase during the toluene evaporation. The proposed film-forming technique makes it possible to modulate the thickness and shape of the films by selecting the quantity and concentration of the organic phase and using various templates, thus opening up a broad range of applications. 相似文献
68.
Although many firms report large benefits from lean implementation, a lot of scepticism still remains regarding attainable results and the possibility to apply Lean approach outside high-volume manufacturing and stable context. In this work, combining field interviews with literature review, theoretical connections have been developed among Lean manufacturing techniques, operational responsiveness and company growth performances. A conceptual model has been proposed for investigating the network of influences among lean practices (supplier management, human resource management, just-in-time and total quality management practices), operational responsiveness (Product mix variety, Product innovation and Time effectiveness) and company growth performances in Italian companies. Using structural equation modelling, a second-order confirmatory factor analysis has been used to test the hypothesised relationships in the structural models. This study highlights that the operational responsiveness is only partially connected to a Lean strategy of a company. Indeed, the lean practices implementations are negatively influenced by product mix variety and innovation, while positively influenced by time effectiveness variables. Moreover, product mix variety and time effectiveness are the main characteristics of the operational responsiveness that positively influences company growth performances. So time effectiveness could be considered as a mediator between Lean best practices and firm growth. Moreover, no direct relationship has been found between lean bundles and firm’s performances. Lack of resources and mainly poor communication and managers’ commitment and support seem to be the main obstacles of lean implementation and success. 相似文献
69.
Electroactive Ionic Soft Actuators with Monolithically Integrated Gold Nanocomposite Electrodes 下载免费PDF全文
Yunsong Yan Tommaso Santaniello Luca Giacomo Bettini Chloé Minnai Andrea Bellacicca Riccardo Porotti Ilaria Denti Gabriele Faraone Marco Merlini Cristina Lenardi Paolo Milani 《Advanced materials (Deerfield Beach, Fla.)》2017,29(23)
Electroactive ionic gel/metal nanocomposites are produced by implanting supersonically accelerated neutral gold nanoparticles into a novel chemically crosslinked ion conductive soft polymer. The ionic gel consists of chemically crosslinked poly(acrylic acid) and polyacrylonitrile networks, blended with halloysite nanoclays and imidazolium‐based ionic liquid. The material exhibits mechanical properties similar to that of elastomers (Young's modulus ≈ 0.35 MPa) together with high ionic conductivity. The fabrication of thin (≈100 nm thick) nanostructured compliant electrodes by means of supersonic cluster beam implantation (SCBI) does not significantly alter the mechanical properties of the soft polymer and provides controlled electrical properties and large surface area for ions storage. SCBI is cost effective and suitable for the scaleup manufacturing of electroactive soft actuators. This study reports the high‐strain electromechanical actuation performance of the novel ionic gel/metal nanocomposites in a low‐voltage regime (from 0.1 to 5 V), with long‐term stability up to 76 000 cycles with no electrode delamination or deterioration. The observed behavior is due to both the intrinsic features of the ionic gel (elasticity and ionic transport capability) and the electrical and morphological features of the electrodes, providing low specific resistance (<100 Ω cm?2), high electrochemical capacitance (≈mF g?1), and minimal mechanical stress at the polymer/metal composite interface upon deformation. 相似文献
70.
The organization of modern economies is built upon an efficient transport system and an increasing role is played by the logistics sector in overcoming the constraints of time and distance in modern supply chains. While a large body of literature is dedicated to the spatial distribution of firms and firm location choice in general, surprisingly little is still known about the location patterns of logistics firms, and more specifically about the role of accessibility in their location decisions. We use geo-referenced firm level data along with detailed information on transport infrastructure in order to investigate the geography of logistics firms in Spain. We place specific attention to the relationship between logistics firm location, accessibility, and urban structure. Our results show that these firms are located closer to highways and other transport infrastructure compared to other sectors and that the logistics sector is highly urbanized. Yet, they are also locating increasingly in suburban locations and to some extent in extra-urban locations with good accessibility while central cities of urban areas have experienced a declining share of logistics firms. 相似文献