213 research outputs found

    Rhamnaceae asociadas a mieles fétidas en Argentina

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    Melissopalynological analysis of six honey samples, commercially rejected for its fetid odour, was performed. These honeys were produced from Espinal and Pampeana Phytogeographical Provinces. The main nectar sources that characterized monofloral honeys belong to the following families: Rhamnaceae (Discaria americana, Scutia buxifolia) and Calyceraceae (Acicarpha tribuloides) along with pollen of S. buxifolia as secondary. According with the results of the present study it seems that the odour has its origin in the Rhamnaceae flower

    Development of barley and yeast β-glucan aerogels for drug delivery by supercritical fluids

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    Polysaccharide aerogels are a good alternative as carriers for drug delivery, since they allow high loading of the active compounds in matrices that are non-toxic, biocompatible and from a renewable feedstock. In this work, barley and yeast β-glucans aerogels were produced by gelation in aqueous solution, followed by solvent exchange and drying with supercritical CO2. First, viscoelastic properties and melting profile of the hydrogels were determined. Then, the obtained aerogels were analyzed regarding morphology, mechanical properties and behavior in physiological fluid. Both in the hydrogels and in the aerogels, big differences were observed between barley and yeast β-glucans due to their different chain structure and gelation behavior. Finally, impregnation of acetylsalicylic acid was performed at the same time as the drying of the alcogels with supercritical CO2. The release profile of the drug in PBS was analyzed in order to determine the mechanism governing the release from the β-glucan matrix.Authors acknowledge Ministerio de Economía y Competitividad (MINECO) through project CTQ2013-44143-R and project PIP 063/ 147181 from Fundación General of the University of Valladolid for fi- nancial support. M. Salgado thanks to Ministerio de Educación, Ciencia y Deporte (MECD) for her FPU and mobility grants. S. Rodríguez-Rojo acknowledges to MINECO and UVa for her Juan de la Cierva fellowship (JCI-2012-14992). The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement number REGPOT-CT2012- 316331-POLARIS and from the project “Novel smart and biomimetic materials for innovative regenerative medicine approaches” RL1 − ABMR − NORTE-01-0124-FEDER-000016) co-financed by North Portugal Regional Operational Programme (ON.2–O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF).info:eu-repo/semantics/publishedVersio

    Water flows through mussel rafts and their relationship with wind speed in a coastal embayment (Ría de Ares-Betanzos, NW Spain)

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    14 páginas, 4 tablas, 8 figurasKnowledge of water flows through mussel rafts and their controlling factors is required for an ecosystem approach to the sustainable management of this culture in the Galician rías. With this aim, 4 acoustic 2D-ACM current meters were hung from the bow of 4 rafts located in the mussel cultivation areas of the Ría de Ares-Betanzos (NW Spain) during autumn 2007. Simultaneously, an Aanderaa DCM12 Doppler profiler was moored in an area free of rafts in the middle ría. There were differences in the subtidal and tidal dynamics of the middle channel and mussel farm areas. The tide explained 51.5% of the total variance of the surface current in the middle ría. The explained variance in the seed collection areas of Redes (inner ría) and Miranda (outer ría), where only 2–3 rafts are anchored, were 64.1% and 16.8%, respectively. In the cultivation areas of Arnela (inner ría) and Lorbé (middle ría), where 101 and 40 rafts are anchored, 14.3% and 53.4% of the total variance was explained by the tide. These disparities in the contribution of the tide are likely due to a combination of topographic and bathymetric differences among sites and distortions of the natural flow by the rafts and their hanging ropes. Furthermore, there was a marked influence of winds on the subtidal currents within the rafts; contrasting correlation coefficients and lag times between wind speed and currents were observed for the outer and inner sides of the embayment. The filtration rate of the growing mussels and the number of mussels per raft allow an efficient clearing of the particles transported across the hanging ropes by the measured subtidal currents of 2–3 cm s–1 characteristic of the cultivation areas of Arnela and LorbéPROINSA Mussel Farm, codes CSIC20061089 and 0704101100001Xunta de Galicia PGIDIT06RMA018E and PGIDIT09MMA038EESSMA project Spain–Canada Grant of MICINNPeer reviewe

    Role of upstream stimulatory factor 2 in glutamate dehydrogenase gene transcription

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    Glutamate dehydrogenase (Gdh) plays a central role in ammonia detoxification by catalysing reversible oxidative deamination of L-glutamate into α-ketoglutarate using NAD+ or NADP+ as cofactor. To gain insight into transcriptional regulation of glud, the gene that codes for Gdh, we isolated and characterised the 5' flanking region of glud from gilthead sea bream (Sparus aurata). In addition, tissue distribution, the effect of starvation as well as short- and long-term refeeding on Gdh mRNA levels in the liver of S. aurata were also addressed. 5'-deletion analysis of glud promoter in transiently transfected HepG2 cells, electrophoretic mobility shift assays, chromatin immunoprecipitation (ChIP) and site-directed mutagenesis allowed us to identify upstream stimulatory factor 2 (Usf2) as a novel factor involved in the transcriptional regulation of glud. Analysis of tissue distribution of Gdh and Usf2 mRNA levels by reverse transcriptase-coupled quantitative real-time PCR (RT-qPCR) showed that Gdh is mainly expressed in the liver of S. aurata, while Usf2 displayed ubiquitous distribution. RT-qPCR and ChIP assays revealed that long-term starvation down-regulated the hepatic expression of Gdh and Usf2 to similar levels and reduced Usf2 binding to glud promoter, while refeeding resulted in a slow but gradial restoration of both Gdh and Usf2 mRNA abundance. Herein, we demonstrate that Usf2 transactivates S. aurata glud by binding to an E-box located in the proximal region of glud promoter. In addition, our findings provide evidence for a new regulatory mechanism involving Usf2 as a key factor in the nutritional regulation of glud transcription in the fish liver

    Membrane particles from mesenchymal stromal cells reduce the expression of fibrotic markers on pulmonary cells

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    Background: Idiopathic pulmonary fibrosis (IPF) is a devastating lung disease with limited treatment options in which the telomere shortening is a strong predictive factor of poor prognosis. Mesenchymal stromal cells (MSC) administration is probed in several experimental induced lung pathologies; however, MSC might stimulate fibrotic processes. A therapy that avoids MSC side effects of transformation would be an alternative to the use of living cells. Membranes particles (MP) are nanovesicles artificially generated from the membranes of MSC containing active enzymes involved in ECM regeneration. We aimed to investigate the anti-fibrotic role of MP derived from MSC in an in vitro model of pulmonary fibrosis. Methods: Epithelial cells (A549) and lung fibroblasts, from IPF patients with different telomere length, were co-cultured with MP and TGF-β for 48h and gene expression of major pro-fibrotic markers were analyzed. Results: About 90% of both types of cells effectively took up MP without cytotoxic effects. MP decreased the expression of profibrotic proteins such as Col1A1, Fibronectin and PAI-1, in A549 cells. In fibroblasts culture, there was a different response in the inhibitory effect of MP on some pro-fibrotic markers when comparing fibroblast from normal telomere length patients (FN) versus short telomere length (FS), but both types showed an inhibition of Col1A1, Tenascin-c, PAI-1 and MMP-1 gene expression after MP treatment

    Altered pathways in methylome and transcriptome longitudinal analysis of normal weight and bariatric surgery women

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    [Abstract] DNA methylation could provide a link between environmental, genetic factors and weight control and can modify gene expression pattern. This study aimed to identify genes, which are differentially expressed and methylated depending on adiposity state by evaluating normal weight women and obese women before and after bariatric surgery (BS). We enrolled 24 normal weight (BMI: 22.5 ± 1.6 kg/m2) and 24 obese women (BMI: 43.3 ± 5.7 kg/m2) submitted to BS. Genome-wide methylation analysis was conducted using Infinium Human Methylation 450 BeadChip (threshold for significant CpG sites based on delta methylation level with a minimum value of 5%, a false discovery rate correction (FDR) of q < 0.05 was applied). Expression levels were measured using HumanHT-12v4 Expression BeadChip (cutoff of p ≤ 0.05 and fold change ≥2.0 was used to detect differentially expressed probes). The integrative analysis of both array data identified four genes (i.e. TPP2, PSMG6, ARL6IP1 and FAM49B) with higher methylation and lower expression level in pre-surgery women compared to normal weight women: and two genes (i.e. ZFP36L1 and USP32) that were differentially methylated after BS. These methylation changes were in promoter region and gene body. All genes are related to MAPK cascade, NIK/NF-kappaB signaling, cellular response to insulin stimulus, proteolysis and others. Integrating analysis of DNA methylation and gene expression evidenced that there is a set of genes relevant to obesity that changed after BS. A gene ontology analysis showed that these genes were enriched in biological functions related to adipogenesis, orexigenic, oxidative stress and insulin metabolism pathways. Also, our results suggest that although methylation plays a role in gene silencing, the majority of effects were not correlated.São Paulo Research Foundation; 2017/07220-7São Paulo Research Foundation; #2016/05638-1São Paulo Research Foundation; #2013/12819-4São Paulo Research Foundation; #2015/18669-0Instituto de Salud Carlos III; PI17/01287Ministerio de Economía y Empresa; MTM2014-52876-RMinisterio de Economía y Empresa; MTM2017-82724-RXunta de Galicia; ED431C-2016-015Xunta de Galicia; ED431G/0

    Long-Term Habitat Degradation Drives Neotropical Macrophyte Species Loss While Assisting the Spread of Invasive Plant Species

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    The spread of invasive macrophyte species is a pressing threat to neotropical shallow lakes. Yet there are few studies addressing the full extent of biotic and abiotic changes that may occur in response to invasive species. Less is known of how other human-induced stressors such as eutrophication and lake draining may interact over time with invasive macrophytes to influence biodiversity. We combined limnological observations with paleoecological data from Fúquene Lake, Colombia, a eutrophic neotropical shallow lake, to provide information on the current and long-term (decades-centuries) dynamics of the spread of two well-established invasive plants Eichhornia crassipes and Egeria densa. We found a unique in macrophyte species composition in areas currently dominated by Egeria and Eichhornia. Eichhornia-dominated areas had 14 macrophyte species, turbid (secchi=19 ± 6 cm) and poorly oxygenated (3.94 ± 2.61 ppm) waters whereas Egeria-rich areas supported 5 species and had clearer (secchi=51 ± 12 cm) and better-oxygenated (6.06 ± 2.4 ppm) waters. Historical macrophyte community shifts were linked to eutrophication and lake level variation and characterized by the loss of charophytes and bryophytes before 1500 CE and subsequent reductions in Nymphaea sp., Potamogeton illinoensis and Najas guadalupensis in the early 1900s (lake draining). Eichhornia crassipes (since 1500 CE) and E. densa (early 1900s) occurred well before proposed dates of introduction (1950s and 1990 respectively). Both species have rapidly expanded since the 1990s along with Azolla filiculoides in response to an inflow water diversion scheme and heavy nutrient loads. Our results suggest that the spread of Eichhornia and Egeria was not responsible for native macrophyte species loss, but that their current dominance is exerting synergistic and antagonistic secondary effects on plant assemblages through habitat modification, competitive exclusion and promotion of habitat heterogeneity across the lake. It could therefore be misleading to suggest that invasive plants causes macrophyte species loss in degraded lakes. We suggest that aggressive species like Eichhornia, Azolla, and Egeria require hydrologically stable and eutrophic environments to spread; thus, management actions should focus on controlling these two factors. Our study demonstrates the need to use a long-term approach to fully-understand the effects of invasive macrophytes
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