Efecto del pH en emulsiones o/w formuladas con proteína de patata y quitosano

Emulsions formulated with healthy ingredients are becoming increasingly popular in the developed world, due to the consumer concern about diseases related to fat and to fatty diets. This study focuses on the O/W emulsions formulated with high-oleic sunflower oil, vegetable protein (potato protein) and chitosan; and deals with the role of pH in the preparation of 40 wt% high-oleic sunflower oil in water emulsions. First of all, potato protein suspensions were prepared in a pH range from 2.0 to 11.5 and enhanced protein solubility was observed with increasing pH. An increase in pH emulsion resulted in more viscoelasticity as demonstrated by the greater values for the storage and lost moduli derived from small amplitude oscillatory shear measurements as well as by the progressive change in the shape of the mechanical spectrum. Flow curves showed shear thinning properties and increasing viscosity values with pH. Z-potential measurements revealed that attractive interactions between potato protein and chitosan progressively increased with pH. The results obtained are consistent with the occurrence of a protein-polysaccharide complex around the interface of oil droplets, which yielded enhanced physical stability.Las emulsiones con ingredientes saludables están adquiriendo más popularidad en el mundo desarrollado, ya que el consumidor es consciente de la relación existente entre algunas enfermedades y las dietas ricas en grasas. En este trabajo se estudian emulsiones O/W formuladas con aceite de girasol alto oleico, una proteína vegetal (proteína de patata) y quitosano. Concretamente, se estudia la influencia del pH en la preparación de emulsiones que contenían 40% de aceite de girasol alto oleico. Se prepararon suspensiones de la proteína en un intervalo de valores de pH comprendido entre 2 y 11,5, observándose un aumento de solubilidad de la proteína al aumentar el pH. El aumento del pH de la emulsión provocó un aumento de la viscoelasticidad, que quedaba reflejado en un incremento de los valores de los módulos de almacenamiento y pérdida, respectivamente, así como, en un cambio progresivo en la forma del espectro mecánico. Por otro lado, las curvas de flujo mostraron propiedades pseudoplásticas y un aumento de los valores de la viscosidad con el pH. Las medidas de potencial Z revelaron la existencia de interacciones atractivas entre la proteína de patata y el quitosano que aumentaban progresivamente con el pH. Los resultados obtenidos pueden explicar la existencia de un complejo proteína de patata-quitosano que se coloca alrededor de las gotas de aceite y que justifica el aumento de estabilidad física

Influence of the formulation on double emulsions containing ecological ingredients prepared by a microfluidic technique

Multiple emulsions have significant potential in myriad applications, including foods, cosmetics, drop networks, controlled microreactors, synthesis of microcapsules and drug delivery systems. Great control of multiple-emulsion drops production can be achieved using microfluidic devices. The field of emulsification through microfluidic devices has in recent years become a popular topic of research. In this work, we used a practical approach to make monodisperse double-emulsions drops with an ultrathin middle layer using a single step emulsification in a capillary microfluidic device. The goal of this study was to investigate the influence of different surfactants and additives on stability and droplet size of W/O/W eco-friendly emulsions formulated with a green solvent (D-Limonene). The incorporation of Pluronic F108 destabilised the double emulsions due to a process of precipitation, forming microcapsules. By contrast, there was a necessity to include Span 80 in the formulation in order to achieve stable double emulsions. The addition of rosin gum or silicone oil did not show any improvement in the stability of these complex emulsions. Finally, the formulation used in ultrathin shell microfluidic device did not produce stable double emulsions in the traditional microfluidic device.Las emulsiones múltiples tienen multitud de aplicaciones en la industria alimentaria, cosméticos, microreactores controlados, síntesis de microcápsulas y sistemas de liberación controlada. Se puede conseguir un gran control de la producción de gotas en emulsiones dobles usando técnicas microfluídicas. En este trabajo se desarrollaron emulsiones dobles formuladas con D-Limoneno usando un dispositivo de microfluídica en un solo paso. El D-Limoneno, el componente principal del aceite esencial de naranja, es un monoterpeno natural que tiene propiedades antioxidantes, bactericida, quimiopreventivas y terapéuticas. El objetivo del presente estudio fue investigar la influencia de diferentes tipos de tensioactivos y aditivos en la formulación de emulsiones dobles ecológicas tipo corteza-ultrafina-núcleo sobre la estabilidad física. Las emulsiones dobles tipo corteza ultra fina y núcleo preparadas con Pluronic P108 sufrieron un fenómeno de desestabilización debido a la precipitación de este tensioactivo polimérico creando microcápsulas. Las emulsiones dobles necesitaron un tensioactivo hidrófobo (Span 80) en la fase media para estabilizarlas. Se consiguieron emulsiones dobles estables utilizando Span 80 como tensioactivo en la fase oleosa y PVA en la fase exterior para la configuración tipo corteza ultrafina-núcleo. Estas condiciones no son extrapolables al tradicional dispositivo de microfluídica.Ministerio de Economía y Competitividad del Gobierno de España-CTQ2015-70700-PComisión Europea (Programa FEDER)-CTQ2015-70700-

Aproximación Proteómica al síndrome de apneas-hipopneas del sueño

Comunicaciones a congreso

Multiplicity dependence of jet-like two-particle correlations in p-Pb collisions at sNN\sqrt{s_{NN}} = 5.02 TeV

Two-particle angular correlations between unidentified charged trigger and associated particles are measured by the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum range 0.7 $< p_{\rm{T}, assoc} < p_{\rm{T}, trig} <$ 5.0 GeV/$c$ is examined, to include correlations induced by jets originating from low momen\-tum-transfer scatterings (minijets). The correlations expressed as associated yield per trigger particle are obtained in the pseudorapidity range $|\eta|<0.9$. The near-side long-range pseudorapidity correlations observed in high-multiplicity p-Pb collisions are subtracted from both near-side short-range and away-side correlations in order to remove the non-jet-like components. The yields in the jet-like peaks are found to be invariant with event multiplicity with the exception of events with low multiplicity. This invariance is consistent with the particles being produced via the incoherent fragmentation of multiple parton--parton scatterings, while the yield related to the previously observed ridge structures is not jet-related. The number of uncorrelated sources of particle production is found to increase linearly with multiplicity, suggesting no saturation of the number of multi-parton interactions even in the highest multiplicity p-Pb collisions. Further, the number scales in the intermediate multiplicity region with the number of binary nucleon-nucleon collisions estimated with a Glauber Monte-Carlo simulation.Comment: 23 pages, 6 captioned figures, 1 table, authors from page 17, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/161

Multi-particle azimuthal correlations in p-Pb and Pb-Pb collisions at the CERN Large Hadron Collider

Measurements of multi-particle azimuthal correlations (cumulants) for charged particles in p-Pb and Pb-Pb collisions are presented. They help address the question of whether there is evidence for global, flow-like, azimuthal correlations in the p-Pb system. Comparisons are made to measurements from the larger Pb-Pb system, where such evidence is established. In particular, the second harmonic two-particle cumulants are found to decrease with multiplicity, characteristic of a dominance of few-particle correlations in p-Pb collisions. However, when a $|\Delta \eta|$ gap is placed to suppress such correlations, the two-particle cumulants begin to rise at high-multiplicity, indicating the presence of global azimuthal correlations. The Pb-Pb values are higher than the p-Pb values at similar multiplicities. In both systems, the second harmonic four-particle cumulants exhibit a transition from positive to negative values when the multiplicity increases. The negative values allow for a measurement of $v_{2}\{4\}$ to be made, which is found to be higher in Pb-Pb collisions at similar multiplicities. The second harmonic six-particle cumulants are also found to be higher in Pb-Pb collisions. In Pb-Pb collisions, we generally find $v_{2}\{4\} \simeq v_{2}\{6\}\neq 0$ which is indicative of a Bessel-Gaussian function for the $v_{2}$ distribution. For very high-multiplicity Pb-Pb collisions, we observe that the four- and six-particle cumulants become consistent with 0. Finally, third harmonic two-particle cumulants in p-Pb and Pb-Pb are measured. These are found to be similar for overlapping multiplicities, when a $|\Delta\eta| > 1.4$ gap is placed.Comment: 25 pages, 11 captioned figures, 3 tables, authors from page 20, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/87

Exposure to N-nitrosamines and other risk factors for gastric cancer in Costa Rican children

Artículo científico -- Universidad de Costa Rica. Instituto de Investigaciones en Salud, 1991The hypothesis that endogenous chemical nitrosation in the normal stomach in early life could play a crucial role in inducing chronic atrophic gastritis/intestinal metaplasia in later life was tested by applying the N-nitrosoproline (NPRO) test to 12-h urine samples from about 50 children (aged 8-14 years) living in high- and low-risk areas for stomach cancer. The median values of NPRO and the sum of four nitrosamino acids analysed were 0.28-0.84 ag/12 h and 0.75-1.75 tig/12 h, respectively. The NPRO level after proline intake was significantly higher in children from a high-risk area than in those from a low-risk area (p < 0.04), and markedly reduced after ingestion of ascorbic acid and proline (p < 0.05). Urinary nitrate level was lower than that of adults. NPRO levels on the day of proline intake, however, correlated well with nitrate levels (p < 0.001), indicating that children in a high-risk area in Costa Rica have high endogenous nitrosation potential. Blood samples were also collected from about 300 children (aged 7-20 years) and analysed for antibodies against Campylabacter pylori, a suspected gastritis-causing bacteria. About 71% of children in both high- and low-risk areas for stomach cancer had antibodies. In addition, raw and cooked beans, which are consumed very frequently in Costa Rica, were collected from families in both areas and analysed for levels of nitrite/nitrate, total N-nitroso compounds and genotoxicity in the SOS chromotest. Mean levels of total N-nitroso compounds in an aqueous extract (pH 2) of cooked bean samples from high- and low-incidence areas were similar (0.4-0.6 nmol/g of cooked beans). Acid-catalysed nitrosation of the same aqueous extracts produced levels up to 2.4 pmol/g of cooked beans. There was no difference in mean levels of nitrosation-dependent total N-nitroso compounds between samples from the two areas. Only two out of 11 extracts from the low-incidence area and two out of 14 from the high-incidence area showed weak direct genotoxicity. After acid-catalysed nitrosation, all samples were genotoxic at similar levelsUniversidad de Costa Rica. Instituto de Investigaciones en Salud.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto de Investigaciones en Salud (INISA

Development of porous Ti6Al4V samples by microsphere sintering

Two differently sized microspheres were sintered at 1300° C and 1400° C from 2 to 8 h in stoneware, alumina, yttria and zirconia moulds. Selecting the appropriate material to be used as a mould remains a critical issue given titanium's high reactivity at elevated temperatures. Optimum mechanical properties were obtained when sintering the smallest microspheres in yttria-coated moulds. Stiffness of the samples was lower than 40% of that of the bulk solid material, which comes closer to that of human cortical bone. Open and interconnected porosity was observed in all the specimens. © 2011 Elsevier B.V. All rights reserved.The translation of this paper was funded by the Polytechnic University of Valencia and the Universitat Jaume I.Reig Cerdá, L.; Amigó Borrás, V.; Busquets Mataix, DJ.; Calero Martinez, JA. (2012). Development of porous Ti6Al4V samples by microsphere sintering. Journal of Materials Processing Technology. 212(1):3-7. https://doi.org/10.1016/j.jmatprotec.2011.06.026S37212

Towards a Synthetic Chloroplast

The evolution of eukaryotic cells is widely agreed to have proceeded through a series of endosymbiotic events between larger cells and proteobacteria or cyanobacteria, leading to the formation of mitochondria or chloroplasts, respectively. Engineered endosymbiotic relationships between different species of cells are a valuable tool for synthetic biology, where engineered pathways based on two species could take advantage of the unique abilities of each mutualistic partner.We explored the possibility of using the photosynthetic bacterium Synechococcus elongatus PCC 7942 as a platform for studying evolutionary dynamics and for designing two-species synthetic biological systems. We observed that the cyanobacteria were relatively harmless to eukaryotic host cells compared to Escherichia coli when injected into the embryos of zebrafish, Danio rerio, or taken up by mammalian macrophages. In addition, when engineered with invasin from Yersinia pestis and listeriolysin O from Listeria monocytogenes, S. elongatus was able to invade cultured mammalian cells and divide inside macrophages.Our results show that it is possible to engineer photosynthetic bacteria to invade the cytoplasm of mammalian cells for further engineering and applications in synthetic biology. Engineered invasive but non-pathogenic or immunogenic photosynthetic bacteria have great potential as synthetic biological devices

Genome-wide association analysis of dementia and its clinical endophenotypes reveal novel loci associated with Alzheimer's disease and three causality networks : The GR@ACE project

Introduction: Large variability among Alzheimer's disease (AD) cases might impact genetic discoveries and complicate dissection of underlying biological pathways. Methods: Genome Research at Fundacio ACE (GR@ACE) is a genome-wide study of dementia and its clinical endophenotypes, defined based on AD's clinical certainty and vascular burden. We assessed the impact of known AD loci across endophenotypes to generate loci categories. We incorporated gene coexpression data and conducted pathway analysis per category. Finally, to evaluate the effect of heterogeneity in genetic studies, GR@ACE series were meta-analyzed with additional genome-wide association study data sets. Results: We classified known AD loci into three categories, which might reflect the disease clinical heterogeneity. Vascular processes were only detected as a causal mechanism in probable AD. The meta-analysis strategy revealed the ANKRD31-rs4704171 and NDUFAF6-rs10098778 and confirmed SCIMP-rs7225151 and CD33-rs3865444. Discussion: The regulation of vasculature is a prominent causal component of probable AD. GR@ACE meta-analysis revealed novel AD genetic signals, strongly driven by the presence of clinical heterogeneity in the AD series