XTHs from Fragaria vesca: Genomic structure and transcriptomic analysis in ripening fruit and other tissues

Indexación: Scopus.Background: Fragaria vesca or 'woodland strawberry' has emerged as an attractive model for the study of ripening of non-climacteric fruit. It has several advantages, such as its small genome and its diploidy. The recent availability of the complete sequence of its genome opens the possibility for further analysis and its use as a reference species. Fruit softening is a physiological event and involves many biochemical changes that take place at the final stages of fruit development; among them, the remodeling of cell walls by the action of a set of enzymes. Xyloglucan endotransglycosylase/hydrolase (XTH) is a cell wall-associated enzyme, which is encoded by a multigene family. Its action modifies the structure of xyloglucans, a diverse group of polysaccharides that crosslink with cellulose microfibrills, affecting therefore the functional structure of the cell wall. The aim of this work is to identify the XTH-encoding genes present in F. vesca and to determine its transcription level in ripening fruit. Results: The search resulted in identification of 26 XTH-encoding genes named as FvXTHs. Genetic structure and phylogenetic analyses were performed allowing the classification of FvXTH genes into three phylogenetic groups: 17 in group I/II, 2 in group IIIA and 4 in group IIIB. Two sequences were included into the ancestral group. Through a comparative analysis, characteristic structural protein domains were found in FvXTH protein sequences. In complement, expression analyses of FvXTHs by qPCR were performed in fruit at different developmental and ripening stages, as well as, in other tissues. The results showed a diverse expression pattern of FvXTHs in several tissues, although most of them are highly expressed in roots. Their expression patterns are not related to their respective phylogenetic groups. In addition, most FvXTHs are expressed in ripe fruit, and interestingly, some of them (FvXTH 18 and 20, belonging to phylogenic group I/II, and FvXTH 25 and 26 to group IIIB) display an increasing expression pattern as the fruit ripens. Conclusion: A discrete group of FvXTHs (18, 20, 25 and 26) increases their expression during softening of F. vesca fruit, and could take part in cell wall remodeling required for softening in collaboration with other cell wall degrading enzymes.https://bmcgenomics.biomedcentral.com/articles/10.1186/s12864-017-4255-

A semi-analytical scheme for highly oscillatory integrals over tetrahedra

This is the peer reviewed version of the following article: [Hospital-Bravo, R., Sarrate, J., and Díez, P. (2017) A semi-analytical scheme for highly oscillatory integrals over tetrahedra. Int. J. Numer. Meth. Engng, 111: 703–723. doi: 10.1002/nme.5474], which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/nme.5474/full. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.This paper details a semi-analytical procedure to efficiently integrate the product of a smooth function and a complex exponential over tetrahedral elements. These highly oscillatory integrals appear at the core of different numerical techniques. Here, the Partition of Unity Method (PUM) enriched with plane waves is used as motivation. The high computational cost or the lack of accuracy in computing these integrals is a bottleneck for their application to engineering problems of industrial interest. In this integration rule, the non-oscillatory function is expanded into a set of Lagrange polynomials. In addition, Lagrange polynomials are expressed as a linear combination of the appropriate set of monomials, whose product with the complex exponentials is analytically integrated, leading to 16 specific cases that are developed in detail. Finally, we present several numerical examples to assess the accuracy and the computational efficiency of the proposed method, compared to standard Gauss-Legendre quadratures.Peer ReviewedPostprint (author's final draft

Dual-Balance Electrodynamic Trap as a Microanalytical Tool for Identifying Gel Transitions and Viscous Properties of Levitated Aerosol Particles

The formation of gelatinous networks within an aerosol particle significantly alters the physicochemical properties of the aerosol material. Existing techniques for studying gel transitions rely on bulk rheometry, which is limited by contact with the sample, or microrheological techniques such as holographic optical tweezers, which rely on expensive equipment and high-powered lasers that can degrade light-absorbing aerosol. Here, we present a new technique to probe the microrheological characteristics of aerosol particles and explore gel formation under atmospheric conditions in a contactless environment without the need for high-power light sources. In a dual-balance quadrupole electrodynamic balance, levitated droplets of opposite polarity are trapped and equilibrated at fixed relative humidity (RH) and then subsequently merged, and the physical characteristics of the merged droplets are monitored as a function of time and RH using imaging techniques. By comparing the RH-dependent characteristics of MgSO4 (known to undergo a gel transition) to glucose and sucrose (known to remain as viscous Newtonian fluids) under fixed equilibration time scales, we demonstrate that gel phase transitions can be identified in aerosol particles, with MgSO4 abruptly transitioning to a rigid microgel at 30% RH. Further, we demonstrate this technique can be used to also measure aerosol viscosity and identify non-Newtonian fluid dynamics in model sea spray aerosol composed of NaCl, CaCl2, and sorbitol. Thus, using this experimental technique, it is possible to distinguish between aerosol compositions that form viscous Newtonian fluids and those that undergo a gel transition or form non-Newtonian fluids. This technique offers a simple and cost-effective analytical tool for probing gel transitions outside of bulk solubility limits, with relevant applications ranging from atmospheric science to microengineering of soft matter materials

Influencia de la estrategia SSAAJ en la disminución de embarazos no planeados en adolescentes atendidos en la ESE Alejandro Próspero Reverend de Santa Marta, 2012 – 2014

Es política del Estado Colombiano educar a los jóvenes en los aspectos relacionados con la Salud Sexual y Reproductiva buscando disminuir los embarazos a temprana edad y no planeados; para ello viene diseñando unas políticas públicas que contribuyan a disminuir esta problemática de salud pública. En materia del marco legal es obligación que las Instituciones Prestadoras de Salud (IPS) prestar un servicio optimo que consiste en tener un espacio físico, recurso humano entrenado en manejo de adolescentes y jóvenes rompiendo con toda barrera burocrática para acceder al servicio de salud, ofreciendo un trato amigable, preferencial y oportuno a todo joven o adolescente que requiera el servicio. En Santa Marta a partir de la primera década del siglo XXI se viene implementando unas políticas públicas de salud sexual y reproductivas claras esperando impactar positivamente en la población objeto. El propósito del presente estudio era analizar el impacto que ha tenido la implementación de la estrategia SSAAJ en los adolescentes y jóvenes de la ciudad de Santa Marta, a través de la educación en pares que realiza el Grupo Juvenil “Pescadores de la Salud” desde el 2012 al 2014.Universidad Libre Seccional Barranquilla -- Ciencias de la Salud -- Especialización en Auditoría de Servicios de Salu

Ion-Molecule Interactions Enable Unexpected Phase Transitions in Organic-Inorganic Aerosol

Atmospheric aerosol particles are commonly complex, aqueous organic-inorganic mixtures, and accurately predicting the properties of these particles is essential for air quality and climate projections. The prevailing assumption is that aqueous organic-inorganic aerosols exist predominately with liquid properties and that the hygroscopic inorganic fraction lowers aerosol viscosity relative to the organic fraction alone. Here, in contrast to those assumptions, we demonstrate that increasing inorganic fraction can increase aerosol viscosity (relative to predictions) and enable a humidity-dependent gel phase transition through cooperative ion-molecule interactions that give rise to long-range networks of atmospherically relevant low-mass oxygenated organic molecules (180 to 310 Da) and divalent inorganic ions. This supramolecular, ion-molecule effect can drastically influence the phase and physical properties of organic-inorganic aerosol and suggests that aerosol may be (semi)solid under more conditions than currently predicted. These observations, thus, have implications for air quality and climate that are not fully represented in atmospheric models

Lagrangian Time Series Models for Ocean Surface Drifter Trajectories

This paper proposes stochastic models for the analysis of ocean surface trajectories obtained from freely-drifting satellite-tracked instruments. The proposed time series models are used to summarise large multivariate datasets and infer important physical parameters of inertial oscillations and other ocean processes. Nonstationary time series methods are employed to account for the spatiotemporal variability of each trajectory. Because the datasets are large, we construct computationally efficient methods through the use of frequency-domain modelling and estimation, with the data expressed as complex-valued time series. We detail how practical issues related to sampling and model misspecification may be addressed using semi-parametric techniques for time series, and we demonstrate the effectiveness of our stochastic models through application to both real-world data and to numerical model output.Comment: 21 pages, 10 figure

Increasing uncoupling protein-2 in pancreatic beta cells does not alter glucose-induced insulin secretion but decreases production of reactive oxygen species

Aims/hypothesis: Levels of uncoupling protein-2 (UCP2) are regulated in the pancreatic beta cells and an increase in the protein level has been associated with mitochondrial uncoupling and alteration in glucose-stimulated insulin secretion. However, it is not clear whether an increase in uncoupling protein-2 per se induces mitochondrial uncoupling and affects ATP generation and insulin secretion. Materials and methods: Transgenic mice with beta cell-specific overexpression of the human UCP2 gene and INS-1 cells with doxycycline-inducible overproduction of the protein were generated and the consequences of increased levels of UCP2 on glucose-induced insulin secretion and on parameters reflecting mitochondrial uncoupling were determined. Results: In transgenic mice, an increase in beta cell UCP2 protein concentration did not significantly modify plasma glucose and insulin levels. Glucose-induced insulin secretion and elevation in the ATP/ADP ratio were unaltered by an increase in UCP2 level. In INS-1 cells, a similar increase in UCP2 level did not modify glucose-induced insulin secretion, cytosolic ATP and ATP/ADP ratio, or glucose oxidation. Increased levels of UCP2 did not modify the mitochondrial membrane potential and oxygen consumption. Increased UCP2 levels decreased cytokine-induced production of reactive oxygen species. Conclusion/interpretation: The results obtained in transgenic mice and in the beta cell line do not support the hypothesis that an increase in UCP2 protein per se uncouples the mitochondria and decreases glucose-induced insulin secretion. In contrast, the observation that increased UCP2 levels decrease cytokine-induced production of reactive oxygen species indicates a potential protective effect of the protein on beta cells, as observed in other cell type

Are the responses of the U.S. economy asymmetric in energy price increases and decreases?

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/88042/1/QE99.pd

Temperature Shifts for Extraction and Purification of Zygomycetes Chitosan with Dilute Sulfuric Acid

The temperature-dependent hydrolysis and solubility of chitosan in sulfuric acid solutions offer the possibility for chitosan extraction from zygomycetes mycelia and separation from other cellular ingredients with high purity and high recovery. In this study, Rhizomucor pusillus biomass was initially extracted with 0.5 M NaOH at 120 °C for 20 min, leaving an alkali insoluble material (AIM) rich in chitosan. Then, the AIM was subjected to two steps treatment with 72 mM sulfuric acid at (i) room temperature for 10 min followed by (ii) 120 °C for 45 min. During the first step, phosphate of the AIM was released into the acid solution and separated from the chitosan-rich residue by centrifugation. In the second step, the residual AIM was re-suspended in fresh 72 mM sulfuric acid, heated at 120 °C and hot filtered, whereby chitosan was extracted and separated from the hot alkali and acid insoluble material (HAAIM). The chitosan was recovered from the acid solution by precipitation at lowered temperature and raised pH to 8–10. The treatment resulted in 0.34 g chitosan and 0.16 g HAAIM from each gram AIM. At the start, the AIM contained at least 17% phosphate, whereas after the purification, the corresponding phosphate content of the obtained chitosan was just 1%. The purity of this chitosan was higher than 83%. The AIM subjected directly to the treatment with hot sulfuric acid (at 120 °C for 45 min) resulted in a chitosan with a phosphate impurity of 18.5%

A novel gene cluster allows preferential utilization of fucosylated milk oligosaccharides in Bifidobacterium longum subsp. longum SC596

La microbiota intestinal infantil es a menudo colonizada por dos subespecies de Bifidobacterium longum: subsp. infantis (B. infantis) y subsp. longum (B. longum). El crecimiento competitivo de B. infantis en el intestino del neonato ha sido vinculado a la utilización de oligosacáridos (HMO) en la leche humana. Sin embargo, poco se sabe sobre cómo B. longum en el consumo de HMO. En este estudio, las cepas B. longum transmitidas mostraron diferentes fenotipos de crecimiento de HMO. Mientras que todas las cepas utilizadas eficientemente con lacto-N-tetraosa, focalizaron ciertas cepas, que, además, metabolizaron el HMO. El B. longum SC596 creció vigorosamente en el HMO, y la glycocaracterización reveló una preferencia por el consumo de HMO fucosilados. El transcriptomes SC596 durante la etapa temprana de crecimiento sobre HMO se asemeja más al crecimiento de la fucosilactosa, pasando más tarde a un patrón similar al crecimiento en el HMO neutro. El B. longum SC596 contiene un gen novedoso cerrado dedicado a la utilización de HMO fucosilado, incluyendo los genes para la importación de moléculas fucosiladas, metabolismo fucoso y dos α-fucosidasas. Este grupo mostró una inducción modular durante el crecimiento temprano de HMO y fucosilactosa. Este trabajo aclara el genoma y la variabilidad fisiológica del bebé portador de B. longum en el consumo de HMO, que se asemeja a B. infantis. La capacidad de consumir preferentemente HMO fucosilado sugiere una ventaja competitiva para estas singulares de las cepas de B. longum en el lactante alimentado con tripa.The infant intestinal microbiota is often colonized by two subspecies of Bifidobacterium longum: subsp. infantis (B. infantis) and subsp. longum (B. longum). Competitive growth of B. infantis in the neonate intestine has been linked to the utilization of human milk oligosaccharides (HMO). However, little is known how B. longum consumes HMO. In this study, infant-borne B. longum strains exhibited varying HMO growth phenotypes. While all strains efficiently utilized lacto-N-tetraose, certain strains additionally metabolized fucosylated HMO. B. longum SC596 grew vigorously on HMO, and glycoprofiling revealed a preference for consumption of fucosylated HMO. Transcriptomes of SC596 during early-stage growth on HMO were more similar to growth on fucosyllactose, transiting later to a pattern similar to growth on neutral HMO. B. longum SC596 contains a novel gene cluster devoted to the utilization of fucosylated HMO, including genes for import of fucosylated molecules, fucose metabolism and two α-fucosidases. This cluster showed a modular induction during early growth on HMO and fucosyllactose. This work clarifies the genomic and physiological variation of infant-borne B. longum to HMO consumption, which resembles B. infantis. The capability to preferentially consume fucosylated HMO suggests a competitive advantage for these unique B. longum strains in the breast-fed infant gut.• National Institutes of Health Awards AT007079, HD065122 y AT008759 • Peter J. Shields Endowed Chair in Dairy Food Science • Conicyt Fondecyt: Beca de iniciación 11130518 • Ministerio de Educación y Ciencia y Universidad de Extremadura.peerReviewe