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排序方式: 共有185条查询结果,搜索用时 15 毫秒
81.
Divya Bharat Rafaela Ramos Mororo Cavalcanti Chrissa Petersen Nathan Begaye Brett Ronald Cutler Marcella Melo Assis Costa Renata Kelly Luna Gomes Ramos Marina Ramos Ferreira Youyou Li Leena P. Bharath Emma Toolson Paul Sebahar Ryan E. Looper Thunder Jalili Namakkal S. Rajasekaran Zhenquan Jia J. David Symons Pon Velayutham Anandh Babu 《Molecular nutrition & food research》2018,62(2)
82.
Marta Clos-Sansalvador Sergio G. Garcia Miriam Morn-Font Charles Williams Niels-Christian Reichardt Juan M. Falcn-Prez Antoni Bayes-Genis Santiago Roura Marcella Franquesa Marta Mongui-Tortajada Francesc E. Borrs 《International journal of molecular sciences》2022,23(17)
Mesenchymal stromal cell-derived extracellular vesicles (MSC-EV) are widely considered as a cell-free therapeutic alternative to MSC cell administration, due to their immunomodulatory and regenerative properties. However, the interaction mechanisms between EV and target cells are not fully understood. The surface glycans could be key players in EV–cell communication, being specific molecular recognition patterns that are still little explored. In this study, we focused on the role of N-glycosylation of MSC-EV as mediators of MSC-EV and endothelial cells’ interaction for subsequent EV uptake and the induction of cell migration and angiogenesis. For that, EV from immortalized Wharton’s Jelly MSC (iWJ-MSC-EV) were isolated by size exclusion chromatography (SEC) and treated with the glycosidase PNGase-F in order to remove wild-type N-glycans. Then, CFSE-labelled iWJ-MSC-EV were tested in the context of in vitro capture, agarose-spot migration and matrigel-based tube formation assays, using HUVEC. As a result, we found that the N-glycosylation in iWJ-MSC-EV is critical for interaction with HUVEC cells. iWJ-MSC-EV were captured by HUVEC, stimulating their tube-like formation ability and promoting their recruitment. Conversely, the removal of N-glycans through PNGase-F treatment reduced all of these functional activities induced by native iWJ-MSC-EV. Finally, comparative lectin arrays of iWJ-MSC-EV and PNGase-F-treated iWJ-MSC-EV found marked differences in the surface glycosylation pattern, particularly in N-acetylglucosamine, mannose, and fucose-binding lectins. Taken together, our results highlight the importance of N-glycans in MSC-EV to permit EV–cell interactions and associated functions. 相似文献
83.
Andreia Maria da Anunciao Gomes Marcelo Manzi Marinho Marcella Coelho Berjante Mesquita Ana Carolina Coelho Prestes Miquel Lürling Sandra M. F. O. Azevedo 《Lakes & Reservoirs: Research and Management》2020,25(3):275-282
Both global warming and eutrophication are predicted to promote cyanobacterial blooms. At the same time, how tropical phytoplankton communities exhibiting different trophic state systems will respond to temperature variations is less clear. To investigate the effects of temperature changes and nutrient additions on phytoplankton communities, and gain insights regarding possible resistance to these effects, the present study focused on testing the hypothesis that temperature variations and nutrient additions will have a stronger effect on cyanobacteria dominance in eutrophic water system than in oligo‐mesotrophic water systems. Experiments were conducted with phytoplankton communities from two aquatic ecosystems exhibiting different trophic states. To this end, water samples from a eutrophic and oligo‐mesotrophic system were collected and incubated at 25 and 30ºC. Samples receiving additional surplus nitrogen (N) and phosphorus (P) inputs were included to serve as eutrophication treatments. The study results indicated that temperature variations alone did not promote cyanobacteria in water from either the oligo‐mesotrophic or eutrophic water system. However, nutrient enrichment of the water from the eutrophic system significantly boosted the cyanobacteria, with the biomass increasing by factor of 10 for both the 25°C and 30°C treatments. In contrast, eutrophication of the water from the oligo‐mesotrophic system did not change the relative contribution of phytoplankton groups, with the response ratios being much lower than those for the water from the eutrophic system. Although based on a simple experimental design, the results of the present study suggest that cyanobacteria dominance is favoured by further nutrient additions for eutrophic water systems, independently of any direct temperature effects, and that more pristine environments possess some resistance against eutrophication effects. Since global warming is assumed to indirectly intensify eutrophication symptoms, the results of the present study underscore the importance of nutrient control. 相似文献
84.
Cascianelli Silvia Cornia Marcella Baraldi Lorenzo Cucchiara Rita 《International Journal on Document Analysis and Recognition》2022,25(3):207-217
International Journal on Document Analysis and Recognition (IJDAR) - Handwritten Text Recognition (HTR) in free-layout pages is a challenging image understanding task that can provide a relevant... 相似文献
85.
Stefano Sorrentino Roberto Ascari Emanuela Maderna Marcella Catania Bernardino Ghetti Fabrizio Tagliavini Giorgio Giaccone Giuseppe Di Fede 《International journal of molecular sciences》2021,22(5)
Alzheimer’s disease (AD) is increasingly recognized as a highly heterogeneous disorder occurring under distinct clinical and neuropathological phenotypes. Despite the molecular determinants of such variability not being well defined yet, microglial cells may play a key role in this process by releasing distinct pro- and/or anti-inflammatory cytokines, potentially affecting the expression of the disease. We carried out a neuropathological and biochemical analysis on a series of AD brain samples, gathering evidence about the heterogeneous involvement of microglia in AD. The neuropathological studies showed differences concerning morphology, density and distribution of microglial cells among AD brains. Biochemical investigations showed increased brain levels of IL-4, IL-6, IL-13, CCL17, MMP-7 and CXCL13 in AD in comparison with control subjects. The molecular profiling achieved by measuring the brain levels of 25 inflammatory factors known to be involved in neuroinflammation allowed a stratification of the AD patients in three distinct “neuroinflammatory clusters”. These findings strengthen the relevance of neuroinflammation in AD pathogenesis suggesting, in particular, that the differential involvement of neuroinflammatory molecules released by microglial cells during the development of the disease may contribute to modulate the characteristics and the severity of the neuropathological changes, driving—at least in part—the AD phenotypic diversity. 相似文献
86.
Marcella G. C. Xavier Bismarck L. Silva Amauri Garcia José E. Spinelli 《Advanced Engineering Materials》2018,20(7)
87.
Marcella Bonazzoli Victorita Dolean Frédéric Hecht Francesca Rapetti 《Computers & Mathematics with Applications》2018,75(5):1498-1514
In this paper we focus on high order finite element approximations of the electric field combined with suitable preconditioners, to solve the time-harmonic Maxwell’s equations in waveguide configurations. The implementation of high order curl-conforming finite elements is quite delicate, especially in the three-dimensional case. Here, we explicitly describe an implementation strategy, which has been embedded in the open source finite element software FreeFem++ (http://www.freefem.org/ff++/). In particular, we use the inverse of a generalized Vandermonde matrix to build basis functions in duality with the degrees of freedom, resulting in an easy-to-use but powerful interpolation operator. We carefully address the problem of applying the same Vandermonde matrix to possibly differently oriented tetrahedra of the mesh over the computational domain. We investigate the preconditioning for Maxwell’s equations in the time-harmonic regime, which is an underdeveloped issue in the literature, particularly for high order discretizations. In the numerical experiments, we study the effect of varying several parameters on the spectrum of the matrix preconditioned with overlapping Schwarz methods, both for 2d and 3d waveguide configurations. 相似文献
88.
Tiling systems are a well accepted model to define recognizable two-dimensional languages but they are not an effective device for recognition unless a scanning strategy for the pictures is fixed. We define a tiling automaton as a tiling system equipped with a scanning strategy and a suitable data structure. The class of languages accepted by tiling automata coincides with the REC family. In this framework it is possible to define determinism, non-determinism and unambiguity. Then (deterministic) tiling automata are compared with the other known (deterministic) automata models for two-dimensional languages. 相似文献
89.
de Oliveira Rezende Marilia Saade Marcella Ruschi Mendes Nunes Andra Oliveira da Silva Vanessa Gomes Moris Virgnia Aparecida Silva Silva Diogo Aparecido Lopes 《Clean Technologies and Environmental Policy》2022,24(5):1535-1552
Clean Technologies and Environmental Policy - Lean and Green seeks to increase added value and reduce waste generation, while also improving environmental sustainability performance in production... 相似文献
90.
Franceline Aparecida Lopes Giovana Ribeiro Ferreira Marcella Rocha Franco Thiago Schimitberger Luiz Oliveira de Faria Rodrigo Fernando Bianchi 《应用聚合物科学杂志》2018,135(13)
This article presents a novel radiochromic film for selective detection of low‐medium (0–10 kGy) gamma radiation (60Co) doses. This dosimeter is based on a printed fluorescent multilayer structure comprising a paper substrate having layers of copper phthalocyanine (DY220) (a green emitter material) on the bottom, and layers of poly[2‐methoxy‐5(2′‐ethylhexyloxy)‐p‐phenylenevinylene] (MEH‐PPV) (a green‐light absorber, red emitter, and radiation sensitive polymer) on the top. The effect of gamma radiation on the optical properties of DY220/MEH‐PPV was described: it was observed as a strong correlation between radiation dose and fluorescent, color coordinates for CIE (1931) chromatic diagram, and Pantone color reference of the dosimeter. The rate of these changes can be altered by manipulation of top–bottom layers to represent easily the radiation dose to be determined in a wide range. This versatile dosimeter has many uses in the field of food radiation for monitoring, quality assurance, and control of the gamma radiation process. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45729. 相似文献