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171.
Maria del Mar Rigo-Adrover àngels Franch Margarida Castell Francisco José Pérez-Cano 《PloS one》2016,11(11)
This study aimed to investigate the effect of supplementation with the probiotic Bifidobacterium breve M-16V on the maturation of the intestinal and circulating immune system during suckling. In order to achieve this purpose, neonatal Lewis rats were supplemented with the probiotic strain from the 6th to the 18th day of life. The animals were weighed during the study, and faecal samples were obtained and evaluated daily. On day 19, rats were euthanized and intestinal wash samples, mesenteric lymph node (MLN) cells, splenocytes and intraepithelial lymphocytes (IEL) were obtained. The probiotic supplementation in early life did not modify the growth curve and did not enhance the systemic immune maturation. However, it increased the proportion of cells bearing TLR4 in the MLN and IEL, and enhanced the percentage of the integrin αEβ7+ and CD62L+ cells in the MLN and that of the integrin αEβ7+ cells in the IEL, suggesting an enhancement of the homing process of naïve T lymphocytes to the MLN, and the retention of activated lymphocytes in the intraepithelial compartment. Interestingly, B. breve M-16V enhanced the intestinal IgA synthesis. In conclusion, supplementation with the probiotic strain B. breve M-16V during suckling improves the development of mucosal immunity in early life. 相似文献
172.
Verónica Corrales-Sánchez María del Mar Noblejas-López Cristina Nieto-Jiménez Javier Pérez-Peña Juan Carlos Montero Miguel Burgos Eva M. Galán-Moya Atanasio Pandiella Alberto Ocaña 《Journal of cellular and molecular medicine》2020,24(5):3117-3127
Identification of druggable vulnerabilities is a main objective in triple-negative breast cancer (TNBC), where no curative therapies exist. Gene set enrichment analyses (GSEA) and a pharmacological evaluation using a library of compounds were used to select potential druggable combinations. MTT and studies with semi-solid media were performed to explore the activity of the combinations. TNBC cell lines (MDAMB-231, BT549, HS-578T and HCC3153) and an additional panel of 16 cell lines were used to assess the activity of the two compounds. Flow cytometry experiments and biochemical studies were also performed to explore the mechanism of action. GSEA were performed using several data sets (GSE21422, GSE26910, GSE3744, GSE65194 and GSE42568), and more than 35 compounds against the identified functions were evaluated to discover druggable opportunities. Analyses done with the Chou and Talalay algorithm confirmed the synergy of dasatinib and olaparib. The combination of both agents significantly induced apoptosis in a caspase-dependent manner and revealed a pleotropic effect on cell cycle: Dasatinib arrested cells in G0/G1 and olaparib in G2/M. Dasatinib inhibited pChk1 and induced DNA damage measured by pH2AX, and olaparib increased pH3. Finally, the effect of the combination was also evaluated in a panel of 18 cell lines representative of the most frequent solid tumours, observing a particularly synergism in ovarian cancer. Breast cancer, triple negative, dasatinib, olaparib, screening. 相似文献
173.
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
174.
Jaime Carrasco Carlos García-Delgado Rebeca Lavega María L. Tello María De Toro Víctor Barba-Vicente María S. Rodríguez-Cruz María J. Sánchez-Martín Margarita Pérez Gail M. Preston 《Microbial biotechnology》2020,13(6):1933-1947
Microorganisms strongly influence and are required to generate the selective substrate that provides nutrients and support for fungal growth, and ultimately to induce mushroom fructification under controlled environmental conditions. In this work, the fungal and bacterial microbiota living in the different substrates employed in a commercial crop (compost phase I, II and III, flush 1 and 2, and casing material on day 1, 6 and 8 after compost casing and during flush 1 and 2) have been characterized along the different stages of cultivation by metataxonomic analysis (16S rRNA and ITS2), analysis of phospholipid fatty acid content (PLFAs) and RT-qPCR. Additionally, laccase activity and the content of lignin and complex carbohydrates in compost and casing have been quantified. The bacterial diversity in compost and casing increased throughout the crop cycle boosted by the connection of both substrates. As reflected by the PLFAs, the total living bacterial biomass appears to be negatively correlated with the mycelium of the crop. Agaricus bisporus was the dominant fungal species in colonized substrates, displacing the pre-eminent Ascomycota, accompanied by a sustained increase in laccase activity, which is considered to be a major product of protein synthesis during the mycelial growth of champignon. From phase II onwards, the metabolic machinery of the fungal crop degrades lignin and carbohydrates in compost, while these components are hardly degraded in casing, which reflects the minor role of the casing for nourishing the crop. The techniques employed in this study provide a holistic and detailed characterization of the changing microbial composition in commercial champignon substrates. The knowledge generated will contribute to improve compost formulations (selection of base materials) and accelerate compost production, for instance, through biotechnological interventions in the form of tailored biostimulants and to design environmentally sustainable bio-based casing materials. 相似文献
175.
Tribelli Paula M. Pezzoni Magdalena Brito María Gabriela Montesinos Nahuel V. Costa Cristina S. López Nancy I. 《Extremophiles : life under extreme conditions》2020,24(2):265-275
Extremophiles - Pseudomonas extremaustralis is an Antarctic bacterium with high stress resistance, able to grow under cold conditions. It is capable to produce polyhydroxyalkanoates (PHAs) mainly... 相似文献
176.
Michaela A. Mausz María Segovia Aud Larsen Stella A. Berger Jorun K. Egge Georg Pohnert 《Environmental microbiology》2020,22(9):3863-3882
Ocean acidification (OA), a consequence of anthropogenic carbon dioxide (CO2) emissions, strongly impacts marine ecosystems. OA also influences iron (Fe) solubility, affecting biogeochemical and ecological processes. We investigated the interactive effects of CO2 and Fe availability on the metabolome response of a natural phytoplankton community. Using mesocosms we exposed phytoplankton to ambient (390 μatm) or future CO2 levels predicted for the year 2100 (900 μatm), combined with ambient (4.5 nM) or high (12 nM) dissolved iron (dFe). By integrating over the whole phytoplankton community, we assigned functional changes based on altered metabolite concentrations. Our study revealed the complexity of phytoplankton metabolism. Metabolic profiles showed three stages in response to treatments and phytoplankton dynamics. Metabolome changes were related to the plankton group contributing respective metabolites, explaining bloom decline and community succession. CO2 and Fe affected metabolic profiles. Most saccharides, fatty acids, amino acids and many sterols significantly correlated with the high dFe treatment at ambient pCO2. High CO2 lowered the abundance of many metabolites irrespective of Fe. However, sugar alcohols accumulated, indicating potential stress. We demonstrate that not only altered species composition but also changes in the metabolic landscape affecting the plankton community may change as a consequence of future high-CO2 oceans. 相似文献
177.
Jean Armengaud Agnès Delaunay-Moisan Jean-Yves Thuret Eelco van Anken Diego Acosta-Alvear Tomás Aragón Carolina Arias Marc Blondel Ineke Braakman Jean-François Collet René Courcol Antoine Danchin Jean-François Deleuze Jean-Philippe Lavigne Sophie Lucas Thomas Michiels Edward R. B. Moore Jonathon Nixon-Abell Ramon Rossello-Mora Zheng-Li Shi Antonio G. Siccardi Roberto Sitia Daniel Tillett Kenneth N. Timmis Michel B. Toledano Peter van der Sluijs Elisa Vicenzi 《Environmental microbiology》2020,22(6):1997-2000
The current SARS-CoV-2 pandemic is wreaking havoc throughout the world and has rapidly become a global health emergency. A central question concerning COVID-19 is why some individuals become sick and others not. Many have pointed already at variation in risk factors between individuals. However, the variable outcome of SARS-CoV-2 infections may, at least in part, be due also to differences between the viral subspecies with which individuals are infected. A more pertinent question is how we are to overcome the current pandemic. A vaccine against SARS-CoV-2 would offer significant relief, although vaccine developers have warned that design, testing and production of vaccines may take a year if not longer. Vaccines are based on a handful of different designs (i), but the earliest vaccines were based on the live, attenuated virus. As has been the case for other viruses during earlier pandemics, SARS-CoV-2 will mutate and may naturally attenuate over time (ii). What makes the current pandemic unique is that, thanks to state-of-the-art nucleic acid sequencing technologies, we can follow in detail how SARS-CoV-2 evolves while it spreads. We argue that knowledge of naturally emerging attenuated SARS-CoV-2 variants across the globe should be of key interest in our fight against the pandemic. 相似文献
178.
Vélez Debora E. Mestre-Cordero Victoria E. Hermann Romina Perego Juliana Harriet Sofia Fernandez-Pazos María de las Mercedes Mourglia Julieta Marina-Prendes M. Gabriela 《Journal of physiology and biochemistry》2020,76(1):85-98
Journal of Physiology and Biochemistry - The cardioprotective activity of rosuvastatin (R) is yet to be known. The objective of this study was to research whether R perfusion before global ischemia... 相似文献
179.
Lizzete Ruth Torres-Barajas María Teresa Alvarez-Zúñiga Guillermo Mendoza-Hernández 《Preparative biochemistry & biotechnology》2020,50(4):390-400
AbstractAspergillus flavipes FP-500 is a Mexican native strain that has been reported as a good producer of xylanases and pectinases; therefore, it promises a strong impact on biotechnology. To provide an overview of protein secretion by A. flavipes, we carried out a comparative proteome analysis of extracellular proteins in liquid cultures with two heterogeneous agro-industrial residues; corn cob (CC) and wheat bran (WB), as carbon sources. Extracellular proteins obtained from both cultures were identified using MS/MS spectrometry. We identified 134 proteins, which were classified into four groups: glycosyl hydrolases (GH), esterases/proteases, miscellaneous proteins, and unidentified proteins. Around 50% of the total proteins identified were GH such as xylanases, β-xylosidases, β-galactosidases, cellulolytic enzymes like β-glucosidase, endoglucanases, and cellobiohydrolases. From this family, a core of 22 (16%) of the proteins identified were found in both substrates, CC and WB, whereas 30% and 54% were unique for CC and WB, respectively. In the esterases/proteases group, proteases, lipases and esterases like feruloylesterases, and acetyl-xylanesterase were identified. Proteins with diverse functions such as monophosphate dehydrogenase or N-acetylglucosaminidase were present. Here, we present strong evidences indicating that the composition and heterogeneity of the used carbon source determine the specific set of protein secreted by the fungus. 相似文献
180.
María Pérez-Burgos Inmaculada García-Romero Miguel A. Valvano Lotte Søgaard Andersen 《Molecular microbiology》2020,113(6):1189-1208
The rod-shaped cells of Myxococcus xanthus, a Gram-negative deltaproteobacterium, differentiate to environmentally resistant spores upon starvation or chemical stress. The environmental resistance depends on a spore coat polysaccharide that is synthesised by the ExoA-I proteins, some of which are part of a Wzx/Wzy-dependent pathway for polysaccharide synthesis and export; however, key components of this pathway have remained unidentified. Here, we identify and characterise two additional loci encoding proteins with homology to enzymes involved in polysaccharide synthesis and export, as well as sugar modification and show that six of the proteins encoded by these loci are essential for the formation of environmentally resistant spores. Our data support that MXAN_3260, renamed ExoM and MXAN_3026, renamed ExoJ, are the Wzx flippase and Wzy polymerase, respectively, responsible for translocation and polymerisation of the repeat unit of the spore coat polysaccharide. Moreover, we provide evidence that three glycosyltransferases (MXAN_3027/ExoK, MXAN_3262/ExoO and MXAN_3263/ExoP) and a polysaccharide deacetylase (MXAN_3259/ExoL) are important for formation of the intact spore coat, while ExoE is the polyisoprenyl-phosphate hexose-1-phosphate transferase responsible for initiating repeat unit synthesis, likely by transferring N-acetylgalactosamine-1-P to undecaprenyl-phosphate. Together, our data generate a more complete model of the Exo pathway for spore coat polysaccharide biosynthesis and export. 相似文献