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991.
992.
Gustavo Untiveros Lindsay Dezi Megan Gillette Julia Sidor Luigi Strizzi 《International journal of molecular sciences》2021,22(21)
Melanoma is a lethal form of skin cancer triggered by genetic and environmental factors. Excision of early-stage, poorly aggressive melanoma often leads to a successful outcome; however, left undiagnosed these lesions can progress to metastatic disease. This research investigates whether the exposure of poorly aggressive melanoma to certain normal skin cells can explain how non-metastatic melanoma becomes more aggressive while still confined to the skin. To this end, we used a serial co-culture approach to sequentially expose cells from two different, poorly aggressive human melanoma cell lines against normal cells of the skin beginning with normal melanocytes, then epidermal keratinocytes, and finally dermal fibroblasts. Protein extraction of melanoma cells occurred at each step of the co-culture sequence for western blot (WB) analysis. In addition, morphological and functional changes were assessed to detect differences between the serially co-cultured melanoma cells and non-co-cultured cells. Results show that the co-cultured melanoma cells assumed a more mesenchymal morphology and displayed a significant increase in proliferation and invasiveness compared to control or reference cells. WB analysis of protein from the co-cultured melanoma cells showed increased expression of Snail and decreased levels of E-cadherin suggesting that epithelial-to-mesenchymal transition (EMT) is occurring in these co-cultured cells. Additional WB analysis showed increased levels of Nodal protein and signaling and signs of increased Wnt activity in the co-cultured melanoma cells compared to reference cells. These data suggest that interaction between poorly aggressive melanoma cells with normal cells of the skin may regulate the transition from localized, poorly aggressive melanoma to invasive, metastatic disease via Nodal and/or Wnt induced EMT. 相似文献
993.
Fbio Goedel Zacarias Martin Chamberlain Pravia Gustavo Prates Mezzomo 《Fatigue & Fracture of Engineering Materials & Structures》2019,42(4):871-882
One of the most important input data in fatigue analysis is the material fatigue properties. This research aims to present a methodology for assessment of statistical planning of fatigue experiments through a MatLab algorithm developed based on Monte Carlo simulations, which enables to simulate statistically the effects of main parameters used for defining the fatigue test setting and to verify their impact on the relative percentage difference (RPD) in fatigue properties estimation comparing to a reference material. The aspects treated here have not been clearly discussed in the standards. Therefore, the proposed recommendations combined with standards procedures is a tool for test engineers, permitting a fatigue test planning with more background and precision, which can help in decisions about which is the better setup, including the sample size, number of stress levels, stress value in each level, and replication. The methodology and good practices presented in this paper were demonstrated by means of actual data from the literature. 相似文献
994.
Alan Silva dos Santos Thais Cardoso de Oliveira Karla Faquine Rodrigues Amanda Alvarenga Coutinho Silva Gustavo José Lauer Coppio Beatriz Carvalho da Silva Fonseca Evelyn Alves Nunes Simonetti Luciana De Simone Cividanes 《应用聚合物科学杂志》2021,138(46):51355
Pre-impregnated carbon fiber/epoxy resin (CF/epoxy prepreg) gained its popularity for significant stress applications, especially in the aerospace industry, owing to its excellent resistance and low specific mass. However, these CF/epoxy prepregs have a tendency to crack propagation. A solution for the prepregs fragility is the addition of carbon nanotubes (CNTs), especially those functionalized with amino groups, reinforcing the material due to its exceptional mechanical properties. In this work, the influence of the carbon chain length of two different amino-functionalized CNTs from diverse backgrounds (commercial and laboratory growth CNTs) is studied. The nanofillers were added in CF/epoxy prepregs by dry spraying without solvent aid. CNTs' samples were characterized by X-ray photoelectron spectroscopy, Raman spectroscopy, transmission electron microscopy, and thermogravimetric analysis (TGA), while the composites were analyzed by TGA, dynamic-mechanical analysis, and field emission scanning electron microscopy. The various surface treatment occurred at different levels according to the CNTs background, and all samples exhibited a distinct behavior. These differences were also observed in the composites' thermomechanical performance: CNTs functionalized with larger carbon chain amine presented the best results, with an increase of almost 100% in the storage moduli (E'), confirming the efficiency of amino-functionalized CNTs in the reinforcement of CF/epoxy prepregs. 相似文献
995.
Daniel Fritzen Anderson Daleffe Gustavo do Santos De Lucca Jovani Castelan Lirio Schaeffer Ricardo J. Alves de Sousa 《International Journal of Material Forming》2018,11(3):389-404
Incremental Sheet Forming (ISF) and particularly its Single Point (SPIF) variant has been studied intensively over the last years given the potential for low-cost prototyping and small batches production. Numerical and experimental works have been covering a widespan of materials and geometries. This paper fills an important gap regarding studies of the SPIF process applied to brass alloys, and particularly the commonly used Cu-35Zn brass alloy. Despite being a material widely used in industry for centuries, with excellent cold formability and innumerous applications, there is still no relevant information on the mechanical response and properties of this material under SPIF. This research is based in SPIF experiments with brass alloy sheets with different thicknesses (0.50, 0.70 and 1.00 mm), to obtain data such as forming forces or forming fracture lines to be compared against standard forming limit diagrams or against other materials under ISF. Other data like friction during the process was evaluated as well. Fifteen sets of experiments were conducted, using different values of step down (0.10, 0.50 and 1.00 mm) and two forming tools with diameters 10 and 15 mm. 相似文献
996.
Ferrari Gustavo A. Chacham Helio de Oliveira Alan B. Matos Matheus J. S. Batista Ronaldo J. C. Meireles Leonel M. Barboza Ana Paula M. Silvestre Ive Neves Bernardo R. A. Lacerda Rodrigo G. 《Journal of Materials Science》2022,57(11):6223-6232
Journal of Materials Science - In the present work, we apply a microfluidic channel platform to study mechanical and adhesion properties of suspended graphene in contact with oleic acid (a lipid).... 相似文献
997.
Wischenbart Martin Firmenich Sergio Rossi Gustavo Bosetti Gabriela Kapsammer Elisabeth 《Multimedia Tools and Applications》2021,80(5):6785-6809
Multimedia Tools and Applications - In the past decades recommender systems have become a powerful tool to improve personalization on the Web. Yet, many popular websites lack such functionality,... 相似文献
998.
da Costa Faria Martins Suelen dos Santos Marcos Alex Lyra Gustavo Bastos de Souza José Leonaldo Lyra Guilherme Bastos Teodoro Iêdo Ferreira Fábio Freitas Júnior Ricardo Araújo Ferreira dos Santos Almeida Alexsandro Claudio de Souza Renan Cantalice 《Water Resources Management》2022,36(12):4557-4574
Water Resources Management - Evapotranspiration is an important parameter to evaluate soil water deficit and water use efficiency, especially in locations with irregularly distributed... 相似文献
999.
Gustavo Ramos-Espinosa Yuanyuan Wang Johanna M. Brandner Stefan W. Schneider Christian Gorzelanny 《International journal of molecular sciences》2021,22(8)
Chitinase 3-like 1 (CHI3L1) is an enzymatically inactive mammalian chitinase that is associated with tumor inflammation. Previous research indicated that CHI3L1 is able to interact with different extracellular matrix components, such as heparan sulfate. In the present work, we investigated whether the interaction of CHI3L1 with the extracellular matrix of melanoma cells can trigger an inflammatory activation of endothelial cells. The analysis of the melanoma cell secretome indicated that CHI3L1 increases the abundance of various cytokines, such as CC-chemokine ligand 2 (CCL2), and growth factors, such as vascular endothelial growth factor A (VEGF-A). Using a solid-phase binding assay, we found that heparan sulfate-bound VEGF-A and CCL2 were displaced by recombinant CHI3L1 in a dose-dependent manner. Microfluidic experiments indicated that the CHI3L1 altered melanoma cell secretome promoted immune cell recruitment to the vascular endothelium. In line with the elevated VEGF-A levels, CHI3L1 was also able to promote angiogenesis through the release of extracellular matrix-bound pro-angiogenic factors. In conclusion, we showed that CHI3L1 is able to affect the tumor cell secretome, which in turn can regulate immune cell recruitment and blood vessel formation. Accordingly, our data suggest that the molecular targeting of CHI3L1 in the course of cancer immunotherapies can tune patients’ response and antitumoral inflammation. 相似文献
1000.
Neural Processing Letters - The power curve modeling for wind turbines is a key tool used to predict the generated electric power, and to monitor and operate wind turbines, directly affecting the... 相似文献