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881.
Aberrant activation of Wnt/β-catenin signaling is common in most sporadic and inherited colorectal cancer (CRC) cells leading to elevated β-catenin/TCF transactivation. We previously identified the neural cell adhesion molecule L1 as a target gene of β-catenin/TCF in CRC cells. Forced expression of L1 confers increased cell motility, invasion, and tumorigenesis, and the induction of human CRC cell metastasis to the liver. In human CRC tissue, L1 is exclusively localized at the invasive front of such tumors in a subpopulation of cells displaying nuclear β-catenin. We determined whether L1 expression confers metastatic capacities by inducing an epithelial to mesenchymal transition (EMT) and whether L1 cosegregates with cancer stem cell (CSC) markers. We found that changes in L1 levels do not affect the organization or expression of E-cadherin in cell lines, or in invading CRC tissue cells, and no changes in other epithelial or mesenchymal markers were detected after L1 transfection. The introduction of major EMT regulators (Slug and Twist) into CRC cell lines reduced the levels of E-cadherin and induced fibronectin and vimentin, but unlike L1, Slug and Twist expression was insufficient for conferring metastasis. In CRC cells L1 did not specifically cosegregate with CSC markers including CD133, CD44, and EpCAM. L1-mediated metastasis required NF-κB signaling in cells harboring either high or low levels of endogenous E-cadherin. The results suggest that L1-mediated metastasis of CRC cells does not require changes in EMT and CSC markers and operates by activating NF-κβ signaling. 相似文献
882.
883.
Alessia Mori Natale E. Baldaccini Mariella Baratti Chiara Caccamo Francesco Dessì‐Fulgheri Rosario Grasso Said Nouira Ridha Ouni Enrica Pollonara Felipe Rodriguez‐Godoy Maria T. Spena Dimitri Giunchi 《Ibis》2014,156(3):687-692
The Eurasian Stone‐curlew is a species of conservation concern in Europe. We investigate for the first time the extent of population structure among populations sampled from six geographical areas, representing four subspecies inhabiting the western part of the species' distribution. Neither mitochondrial nor nuclear markers fully supported current subspecies boundaries. However, both markers support significant differentiation of the Canary Island populations from those sampled from the Mediterranean. Further work is needed to establish the taxonomic status of this potentially distinct Macaronesian taxon. More broadly, further genetic research is required to design and implement an effective conservation plan for this species. 相似文献
884.
Occurrence, Diversity, and Pathogenicity of Halophilic Vibrio spp. and Non-O1 Vibrio cholerae from Estuarine Waters along the Italian Adriatic Coast 下载免费PDF全文
Elena Barbieri Loredana Falzano Carla Fiorentini Anna Pianetti Wally Baffone Alessia Fabbri Paola Matarrese Annarita Casiere Mohammad Katouli Inger Kühn Roland Mllby Francesca Bruscolini Gianfranco Donelli 《Applied microbiology》1999,65(6):2748-2753
The occurrence, diversity, and pathogenicity of Vibrio spp. were investigated in two estuaries along the Italian Adriatic coast. Vibrio alginolyticus was the predominant species, followed by Vibrio parahaemolyticus, non-O1 Vibrio cholerae, and Vibrio vulnificus. By using a biochemical fingerprinting method, all isolates were grouped into nine phenotypes with similarity levels of 75 to 97.5%. The production of toxins capable of causing cytoskeleton-dependent changes was detected in a large number of Vibrio strains. These findings indicate a significant presence of potentially pathogenic Vibrio strains along the Adriatic coast. 相似文献
885.
886.
Marta Parazzini Federica Sibella Alessia Paglialonga Paolo Ravazzani 《Bioelectromagnetics》2010,31(7):546-555
In the last few years, significant developments have taken place in the field of Wireless Local Area Networks (WLAN), and the popularity of portable devices supporting Wireless Fidelity (Wi‐Fi) is continuously growing. At the same time, the number of Active Implanted Medical Devices (AIMD) being placed in patients is widely increasing and among them, cochlear implants (CI) are becoming a common aid. The goal of this study is to investigate the effect on the electromagnetic field distribution and the specific absorption rate (SAR) due to the presence of a CI in a head model during far‐field exposure to Wi‐Fi frequencies. The head model was obtained by image segmentation, the implant was modelled as a geometric structure, and the exposure sources were modelled as a uniform plane wave (power density = 10 W/m2) at 2.4, 5.2 and 5.8 GHz. Vertical and horizontal polarizations were simulated. Conditions with and without CI were compared. The findings of that are: (1) local differences in the field distribution close to the CI, comparing the head models with or without the CI; (2) higher field strength and point SAR value in the cochlear region very close to the CI; (3) negligible differences in the field strength and point SAR value in the cochlear region far from the CI; (4) negligible variations in the average SAR values in the cochlea and head due to the presence of the CI. The results of this study conclude that insertion of a CI brings moderate localized differences in the E, H and point SAR distribution when evaluated close to the electrode array in the cochlea, while negligible differences are found in the average SAR values both in the cochlea and head, independent of frequency and wave polarization. Bioelectromagnetics 31:546–555, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
887.
Yassin Refahi Argyris Zardilis Gaël Michelin Raymond Wightman Bruno Leggio Jonathan Legrand Emmanuel Faure Laetitia Vachez Alessia Armezzani Anne-Evodie Risson Feng Zhao Pradeep Das Nathanaël Prunet Elliot M. Meyerowitz Christophe Godin Grégoire Malandain Henrik Jönsson Jan Traas 《Developmental cell》2021,56(4):540-556.e8
888.
Alessia Pasqualato Vittorio Lei Alessandra Cucina Simona Dinicola Fabrizio D'Anselmi Sara Proietti Maria Grazia Masiello Alessandro Palombo Mariano Bizzarri 《Cell Adhesion & Migration》2013,7(5):450-459
Unsuccessful cytotoxic anticancer treatments may contribute to tumor morphologic instability and consequent tissue invasion, promoting the selection of a more malignant phenotype. Indeed, morphological changes have been demonstrated to be more pronounced in strongly vs. weakly metastatic cells.By means of normalized bending energy, we have previously quantitatively defined the link between cell shape modifications and the acquisition of a more malignant phenotype by 5-FU-resistant colon cancer cells (HCT-8FUres). Such changes were significantly correlated with an increase in motility speed. Herein, we propose a method to quantitatively analyze the shape of wild and chemoresistant HCT-8 migration front cells during wound healing assay. We evaluated the reliability of parameters (area/perimeter ratio [A/p], circularity, roundness, fractal dimension, and solidity) in describing the biological behavior of the two cell lines, enabling hence in distinguishing the chemoresistant line from the other one. We found solidity index the parameter that better described the difference between chemoresistant and wild cells. Moreover, solidity is able to capture the differences between chemoresistant and wild cells at each time point of the migration process. Indeed, motility speed was found to be inversely correlated with solidity, a quantitative index of cell deformability. Deformability is an outstanding hallmark of the process leading to metastatic spread; consequently, solidity may be considered a marker of acquired metastatic property. 相似文献
889.
890.
Stefania Fioravanti Alessia Pelagalli Lucio Pellacani Fabio Sciubba Maria Cecilia Vergari 《Amino acids》2014,46(8):1961-1970
Chiral (R)-1-phenylethylamine was successfully employed in a tandem aza-Henry addition–reduction reaction to give chiral β-nitro α-trifluoromethyl amines. A subsequent coupling reaction with N-Boc-protected amino acids leads to obtain optically pure CF3-modified dipeptides carrying two different N-protecting groups. These peptidomimetic units are characterized by the presence of the [CH(CF3)NH] group as mimetic of the natural [CONH] peptidic bond and can be used for the synthesis of more complex CF3-modified peptides after selective deprotection of one of the two amine functions. 2D NMR spectral analyses were employed to determine the absolute configurations of all newly synthesized chiral compounds. 相似文献