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21.
Bernard Banaigs Christian Francisco Emmanuel Gonzalez Louis Codomier 《Phytochemistry》1984,23(12):2951-2952
Two new diunsaturated lipids, related to palmitic acid, were isolated from the brown alga Cystoseira barbata, one of which is toxic to mice during P388 lymphocytic leukemia tests. 相似文献
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Zavala-Ortiz Daniel Arturo Ebel Bruno Guedon Emmanuel Marc Annie Barradas-Dermitz Dulce María Hayward-Jones Patricia Margaret Aguilar-Uscanga María Guadalupe 《Bioprocess and biosystems engineering》2020,43(4):747-752
Bioprocess and Biosystems Engineering - Plant suspension culture is attracting interest as a promising platform to produce biological medicines due to the absence of virus, prions or DNA related to... 相似文献
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Aline Queiroz Emmanuel Albuquerque-Souza Leticia Miquelitto Gasparoni Bruno Nunes de Fran a Cibele Pelissari Mar lia Trierveiler Marinella Holzhausen 《World journal of stem cells》2021,13(6):605-618
Inflammatory periodontal disease known as periodontitis is one of the most common conditions that affect human teeth and often leads to tooth loss. Due to the complexity of the periodontium, which is composed of several tissues, its regeneration and subsequent return to a homeostatic state is challenging with the therapies currently available. Cellular therapy is increasingly becoming an alternative in regenerative medicine/dentistry, especially therapies using mesenchymal stem cells, as they can be isolated from a myriad of tissues. Periodontal ligament stem cells (PDLSCs) are probably the most adequate to be used as a cell source with the aim of regenerating the periodontium. Biological insights have also highlighted PDLSCs as promising immunomodulator agents. In this review, we explore the state of knowledge regarding the properties of PDLSCs, as well as their therapeutic potential, describing current and future clinical applications based on tissue engineering techniques. 相似文献
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Ioannis-Dimosthenis S. Adamakis Emmanuel Panteris Anna Cherianidou Eleftherios P. Eleftheriou 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2013,750(1-2):111-120
Bisphenol A (BPA), a widely used chemical in the plastics industry that displays weak oestrogenic properties, is an emerging environmental pollutant, potentially harmful to living organisms. The presumed cytotoxicity of BPA to plant cells has been poorly studied. To understand how BPA might influence plant cell division and affect the underlying cytoskeleton, the effects of BPA on the microtubule (MT) arrays of meristematic root-tip cells of Pisum sativum L. were investigated. Root tips of young seedlings were exposed to 20, 50 and 100 mg/L BPA for 1, 3, 6, 12 and 24 h. The effects of each treatment were determined by means of confocal laser scanning microscopy after immunolabelling of tubulin and counterstaining of DNA, and by use of light and transmission electron microscopy. It was found that BPA affected normal chromosome segregation, hampered the completion of cytokinesis and deranged interphase and mitotic MT arrays. BPA effects were dependent on the stage of each cell at the time of BPA entrance. Moreover, BPA induced the formation of macrotubules with a mean diameter of 32 ± 0.14 nm, compared with 23 ± 0.70 nm for the MT arrays in untreated cells. Finally, all MT arrays and macrotubules were depolymerised upon longer treatment. Taken together, the data suggest that BPA exerts acute anti-mitotic effects on meristematic root-tip cells of P. sativum, MT arrays constitute a primary sub-cellular target of BPA toxicity, and the manifested chromosomal abnormalities could be attributed to the disruption of the MT cytoskeleton. 相似文献
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Motivation
Array-CGH can be used to determine DNA copy number, imbalances in which are a fundamental factor in the genesis and progression of tumors. The discovery of classes with similar patterns of array-CGH profiles therefore adds to our understanding of cancer and the treatment of patients. Various input data representations for array-CGH, dissimilarity measures between tumor samples and clustering algorithms may be used for this purpose. The choice between procedures is often difficult. An evaluation procedure is therefore required to select the best class discovery method (combination of one input data representation, one dissimilarity measure and one clustering algorithm) for array-CGH. Robustness of the resulting classes is a common requirement, but no stability-based comparison of class discovery methods for array-CGH profiles has ever been reported.Results
We applied several class discovery methods and evaluated the stability of their solutions, with a modified version of Bertoni''s -based test [1]. Our version relaxes the assumption of independency required by original Bertoni''s -based test. We conclude that Minimal Regions of alteration (a concept introduced by [2]) for input data representation, sim [3] or agree [4] for dissimilarity measure and the use of average group distance in the clustering algorithm produce the most robust classes of array-CGH profiles.Availability
The software is available from http://bioinfo.curie.fr/projects/cgh-clustering. It has also been partly integrated into "Visualization and analysis of array-CGH"(VAMP)[5]. The data sets used are publicly available from ACTuDB [6]. 相似文献30.