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911.
Janina Burk Heidrun Holland Anne F. Lauermann Tobias May Philipp Siedlaczek Verena Charwat Cornelia Kasper 《Biotechnology and bioengineering》2019,116(6):1417-1426
Multipotent mesenchymal stromal cells (MSC) and MSC-derived products have emerged as promising therapeutic tools. To fully exploit their potential, further mechanistic studies are still necessary and bioprocessing needs to be optimized, which requires an abundant supply of functional MSC for basic research. To address this need, here we used a novel technology to establish a human adipose-derived MSC line with functional characteristics representative of primary MSC. Primary MSC were isolated and subjected to lentiviral transduction with a library of expansion genes. Clonal cell lines were generated and evaluated on the basis of their morphology, immunophenotype, and proliferation potential. One clone (K5 iMSC) was then selected for further characterization. This clone had integrated a specific transgene combination including genes involved in stemness and maintenance of adult stem cells. Favorably, the K5 iMSC showed cell characteristics resembling juvenile MSC, as they displayed a shorter cell length and enhanced migration and proliferation compared with the non-immortalized original primary MSC (p < 0.05). Still, their immunophenotype and differentiation potential corresponded to the original primary MSC and the MSC definition criteria, and cytogenetic analyses revealed no clonal aberrations. We conclude that the technology used is applicable to generate functional MSC lines for basic research and possible future bioprocessing applications. 相似文献
912.
Anne Mouré Elodie Bacou Steffi Bosch Dominique Jegou Apolline Salama David Riochet Olivier Gauthier Gilles Blancho Jean-Paul Soulillou Denis Poncelet Eric Olmos Jean-Marie Bach Mathilde Mosser 《Biotechnology and bioengineering》2019,116(5):1176-1189
The bioartificial pancreas encapsulating pancreatic islets in immunoprotective hydrogel is a promising therapy for Type 1 diabetes. As pancreatic islets are highly metabolically active and exquisitely sensitive to hypoxia, maintaining O2 supply after transplantation remains a major challenge. In this study, we address the O2 limitation by combining silicone-encapsulated CaO2 (silicone-CaO2) to generate O2 with an extracellular hemoglobin O2-carrier coencapsulated with islets. We showed that the hemoglobin improved by 37% the O2-diffusivity through an alginate hydrogel and displayed antioxidant properties neutralizing deleterious reactive O2 species produced by silicone-CaO2. While the hemoglobin alone failed to maintain alginate macroencapsulated neonate pig islets under hypoxia, silicone-CaO2 alone or combined to the hemoglobin restored islet viability and insulin secretion and prevented proinflammatory metabolism (PTGS2 expression). Interestingly, the combination took the advantages of the two individual strategies, improved neonate pig islet viability and insulin secretion in normoxia, and VEGF secretion and PDK1 normalization in hypoxia. Moreover, we confirmed the specific benefits of the combination compared to silicone-CaO2 alone on murine pseudo-islet viability in normoxia and hypoxia. For the first time, our results show the interest of combining an O2 provider with hemoglobin as an effective strategy to overcome O2 limitations in tissue engineering. 相似文献
913.
Ana C. G. Mai Cristiano Q. Albuquerque Valéria M. Lemos Paulo R. Schwingel Gian-Franco Ceni Tatiana D. Saint'Pierre João P. Vieira 《Journal of fish biology》2019,95(5):1207-1214
We analysed the ratios Sr:Ca and Ba:Ca in the otoliths of 55 adults of the southern population of Mugil liza in Brazil (Paraná to Rio Grande do Sul) to investigate its coastal zone use and migratory behaviour. All individual M. liza analysed had Sr:Ca and Ba:Ca values indicating that their birth was in the marine environment, which is consistent with the southern population migration to spawn in the ocean,. Juveniles exhibited at least three coastal use and recruitment strategies (contingents): the majority (89%) of M. liza juveniles migrated toward brackish water. They entered the estuary before completing the first year of life (64%) or after (25%) their first year of life. The remaining 11% did not appear to enter brackish or freshwater water as a nursery or at any point in their life cycle. Some adults returned to the estuary after spawning in the ocean but others (of both sexes) never returned to the estuary after spawning, remaining in the marine environment. The pattern of juvenile habitat use in the Brazilian southern population of M. liza seems to be recurrent throughout the extent of its distribution as a consequence of the reproductive spawning aggregation behaviour, which mixes all contingents (with marine or estuarine preferences). 相似文献
914.
Frances E. Hauser João P. Fontenelle Ahmed A. Elbassiouny Nicholas E. Mandrak Nathan R. Lovejoy 《Journal of fish biology》2019,95(6):1500-1505
We used mitochondrial DNA to assess the genetic structure of endangered lake chubsucker Erimyzon sucetta across its Canadian range. We found unique mitochondrial haplotypes in Lyons Creek, a tributary of the Niagara River that faces a strong potential for habitat deterioration. Lyons Creek may therefore serve as a reservoir of unique genetic diversity. The sensitivity of Lyons Creek, combined with the genetic uniqueness of its E. sucetta population, call for further investigation into whether this population should be considered a separate designatable unit for conservation purposes. 相似文献
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918.
Alex A. Pollen Aparna Bhaduri Madeline G. Andrews Tomasz J. Nowakowski Olivia S. Meyerson Mohammed A. Mostajo-Radji Elizabeth Di Lullo Beatriz Alvarado Melanie Bedolli Max L. Dougherty Ian T. Fiddes Zev N. Kronenberg Joe Shuga Anne A. Leyrat Jay A. West Marina Bershteyn Craig B. Lowe Bryan J. Pavlovic Arnold R. Kriegstein 《Cell》2019,176(4):743-756.e17
919.
de Queiroz João Vitor Vieira José Cavalcante Souza de Oliveira Grasieli Braga Camila Pereira da Cunha Bataglioli Izabela da Silva Janaína Macedo de Paula Araújo Wellington Luiz de Magalhães Padilha Pedro 《Biological trace element research》2019,187(1):291-300
Biological Trace Element Research - Predator fish can accumulate high levels of mercury, which qualifies them as potential indicators of this toxic metal. The predatory species Brachyplatystoma... 相似文献
920.
Schmitt Franz-Josef Campbell Züleyha Yenice Bui Mai Vi Hüls Anne Tomo Tatsuya Chen Min Maksimov Eugene G. Allakhverdiev Suleyman I. Friedrich Thomas 《Photosynthesis research》2019,139(1-3):185-201
Photosynthesis Research - The phototrophic cyanobacterium Halomicronema hongdechloris shows far-red light-induced accumulation of chlorophyll (Chl) f, but the involvement of the pigment in... 相似文献