2,937 research outputs found
Muestreo de zooplancton neustónico
Metodología para obtener muestras de neuston de la fracción mayor de
200 mm, válida tanto para estudios cualitativos como cuantitativos
Extracellular vesicle and soluble fractions of adipose tissue-derived mesenchymal stem cells secretome induce inflammatory cytokines modulation in an in vitro model of discogenic pain
.BACKGROUND CONTEXT: Mesenchymal Stem Cells (MSCs) secretome or conditioned
medium (CM) is a complex cocktail of different molecules, some of which, particularly those con-
tained in extracellular vesicles, already have proven therapeutic applications.
PURPOSE: CM may well represent promising therapy for discogenic pain and the intention of this
work is to assess its therapeutic potential using an in vitro model of this condition.
STUDY DESIGN: This is an experimental study.
METHODS: Our in vitro model comprised Nucleus Pulposus (NP) and Annulus Fibrosus (AF)
cells inflamed with TNF. To assess the potential therapeutic value of CM and its components,
extracellular vesicles (EVs) and soluble culture fraction (SF), cell inflammation took place under 3
different conditions: either in the presence of whole CM, isolated EVs or SF, and concentrations of
pro-inflammatory cytokines, metalloproteinases (MMPs) and neurotrophic factors produced in all
3 cases were compared.
RESULTS: In the presence of whole CM, both in vitro gene expression by the NP and AF test cells
and analysis of their protein content showed high modulatory effects on inflammation and MMP
inhibition. The presence of EVs and SF showed similar but much smaller effects, and this was par-
ticularly marked in the case of NP cells.
CONCLUSIONS: Our results show that, compared to EVs and SF, the presence of whole CM has
the greatest positive effect on the modulation of pro-inflammatory and catabolic factors. These
observations suggest that CM could protect against inflammation and the resulting intervertebral
disc (IVD) degeneration that leads to discogenic pain.
CLINICAL SIGNIFICANCE: Many patients' expectations are not met by current non-operative
and surgical treatments for discogenic low back pain. We propose the use of the MSCs secretomeS
Human impacts on the Northern Iberian Coast: Brominated pollutants.
Plastic and textile products as well as electronical devices are easily flammable products and to reduce fire-related injury and property damage, such materials are commonly covered by the so-called flame retardants (FR). The brominated flame retardants (BFRs) are the largest market group because of their low cost and high-performance efficiency. Nevertheless, as these compounds are additive rather than chemically bound to the products, they can be released into the environment and because they are toxic and persistent organic chemicals and can bioaccumulate, they have become contaminants of concern detectable in the environment, in animals, and in humans. PBDEs (Polybrominated Diphenyl Ethers) are a group of 209 different congeners used as FR and since 2004 banned in the EU. In spite of banned and restriction such chemicals are still detected in the environment and their monitoring necessary.
In 2016 a sampling campaign was carried out covering the North Spanish Atlantic coast from the border with Portugal to the limit with France. The collected sediments were studied to determine sediment characteristics and PBDEs concentrations. Sedimentological characteristics including grain size distribution and total organic content were measured. Gas chromatography coupled to MS detector was used to perform the analytical analysis under QA/QC to guarantee the quality of the results. BDE28, BDE47, BDE66, BDE85, BDE99, BD100, BD153, BDE154 andBD183 have been determined and evaluated against Background assessment criteria (BACs) and Federal Environmental Quality Guidelines (FEQGs). Levels found demonstrate that there is still detectable presence of PBDEs in marine sediments albeit they are well below the FEQG and even frequently below BACs
Application of magnesium hydroxide nanocoatings on cellulose fibers with different refining degrees
Paper aging and protection are of crucial interest for improving the preservations of library collections and archives. Highly aging-resistant cellulose fiber sheets were obtained by treatment with magnesium hydroxide nanoparticles (Mg(OH)(2)). The procedure was tested on the sheets made of bleached (B) and refined unbleached (UB) pine cellulose fibers as well as their 50%/50% mixture (M). The mor and structural properties of the obtained sheets were studied by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) methods. Stress-strain, smoothness and pH measurements were employed to determine the changes in physical-chemical characteristics of the sheets after mixing two types of the fibers and subsequent treatment with Mg(OH)(2). It has been shown that the sheets made of the fiber mixture show a higher tensile index and smoothness. The modification with Mg(OH)(2) nanoparticles induces an increase in the pH of the sheets to slightly basic values (around pH 8), facilitates the inter-fiber bonding and additionally enhances the smoothness of the sheets. Finally, by exposing the sheets to thermo-hygrometric accelerated artificial ageing, it was found that the physical properties of the treated sheets were not significantly dependent on the environmental factors.This study was supported by the Geomaterials 2 Programme (S2013/MIT_2914),the Innovation and Education Ministry (ref. MAT2013-47460-C5-5-P) and the Autonomous Region Program of Madrid, MULTIMAT CHALLENGE (ref.S2013/MIT-2862
Coercive and anisotropy fields in patterned amorphous FeSi submicrometric structures
Amorphous FexSi12x films have been prepared on Si substrates in order to fabricate submicrometric
magnetic structures with soft magnetic behavior. The magnetic properties compositional
dependence of the unpatterned samples has been analyzed to select the Fe content (x50.7) with the
lowest coercive and anisotropy fields values. Arrays of Fe0.7Si0.3 lines have been fabricated by
electron beam lithography combined with a liftoff technique, with typical dimensions of 200 nm
linewidth and 1 mm line spacing. These arrays present coercive fields parallel to the line direction
as small as 9 Oe.Peer reviewe
Phlebotominae (Diptera: psycodidae) fauna in the Chaco region and Cutaneous Leishmaniasis transmission patterns in Argentina
In Argentina, the incidence of American Cutaneous Leishmaniasis (ACL) has shown a steady increase over the last few decades. In the Chaco biogeographical region, specifically, several outbreaks of ACL were recently reported in addition to the usual time-space scattering of ACL cases. However, little is known about the sandfly composition in the eastern, humid Chaco (HC) region or the western, dry Chaco (DC) region. Therefore, phlebotomine captures were performed throughout this region and an analysis of the distribution of reported ACL cases was conducted in order to assess the vector diversity in ACL endemic and epidemic scenarios in the Chaco region. The results support the hypothesis of two distinct patterns: (1) the DC, where Lutzomyia migonei was the most prevalent species, had isolated ACL cases and a zoonotic cycle; (2) the HC, where Lutzomyia neivai was the most prevalent species, had an increase in ACL incidence and outbreaks and an anthropozoonotic cycle. The epidemic risk in the Chaco region may be associated with the current climate trends, landscape modification, connection with other ACL foci, and Lu. neivai predominance and abundance. Therefore, changes in sandfly population diversity and density in the Chaco region are an indicator of emergent epidemic risk in sentinel capture sites.Facultad de Ciencias Naturales y Muse
A transfer matrix method for the analysis of fractal quantum potentials
The scattering properties of quantum particles on fractal potentials at
different stages of fractal growth are obtained by means of the transfer matrix
method. This approach can be easily adopted for project assignments in
introductory quantum mechanics for undergraduates. The reflection coefficients
for both the fractal potential and the finite periodic potential are calculated
and compared. It is shown that the reflection coefficient for the fractal has a
self-similar structure associated with the fractal distribution of the
potential
Towards discard quantification of Data Limited Stocks based in on-board observers data: the case of Spanish fresh trawlers targeting black hake in NW Africa
Quantification of discard per unit effort rates (DPUE) has been proposed by the European Commission as a measure to manage the discarding of commercially fished organisms. In the Spanish fresh trawling fleet operating in North West Africa, both target species of black hakes, Merluccius polli and Merluccius senegalensis are data limited stocks (DLS). Hence, discards of these fleets are even more unknown but not unimportant part of the total catch (retained and discarded). Onboard observer data from commercial surveys from 2016 to 2018 provide a detailed source of scientific information about catches, discards, effort and technical factors in this fleet. This is the first quantitative analysis to model DPUE through generalised linear mixed models (GLMM), based on the explicit distinction between abundance
and technical factors coming from information of observer surveys. We describe the relationship between discards and environment, catches of target and other species, effort of the fleet, spatial and temporal variation in discard accessibility, vessel characteristics, strategy of the skippers and market decisions. Unlike hake catches, discards were higher and more dispersed in shallower than in deeper waters. We identified two separate métiers for the Spanish fresh trawling fleet determined by depth and treated total discards as a stock unit susceptible of being monitored, managed and assessed. The strategy of the skipper appears to have a more important effect on discards than vessel characteristics. This study shows the importance of observer data for this fishery and identifies recommendations for the improvement in the scientific usefulness of logbook information.En prens
Optical binding-driven micropatterning and photo-sculpting with silver nanorods
Controlling the nano- and micropatterning of metal structures is an important requirement for various technological applications in photonics and biosensing. This work presents a method for controllably creating silver micropatterns by laser-induced photosculpting. Photosculpting is driven by plasmonic interactions between pulsed laser radiation and silver nanorods (AgNRs) in aqueous suspension; this process leads to optical binding forces transporting the AgNRs in the surroundings, while electronic thermalization results in photooxidation, melting, and ripening of the AgNRs into well-defined 3D structures. This work call these structures Airy castles due to their structural similarity with a diffraction-limited Airy disk. The photosculpted Airy castles contain emissive Ag nanoclusters, allowing for the visualization and examination of the aggregation process using luminescence microscopy. This work comprehensively examines the factors that define the photosculpting process, namely, the concentration and shape of the AgNRs, as well as the energy, power, and repetition rate of the laser. Finally, this work investigates the potential applications by measuring the metal-enhanced luminescence of a europium-based luminophore using Airy castles.MCIN/AEI/10.13039/501100011033 and the European Regional Development Fund (ERDF). Grant Number: CTQ2017-85658-R
MCIN/AEI/10.13039/501100011033. Grant Number: PID2020-114256RB-I00
European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie. Grant Number: 101007934
Fundação para a Ciência e a Tecnologia, I.P. Grant Numbers: UIDB/00100/2020, 2022.04076.PTD
The multi-reference contrast method: facilitating set enrichment analysis
Set enrichment analysis (SEA) is used to identify enriched biological categories/terms within high-throughput differential expression experiments. This is done by evaluating the proportion of differentially expressed genes against a background reference (BR). However, the choice of the "appropriate" BR is a perplexing problem and results will depend on it. Here, a visualization procedure that integrates results from several BRs and a stability analysis of enriched terms is presented as a tool to aid SEA. The multi-reference contrast method (MRCM) combines results from multiple BRs in a unique picture. The application of the proposed method was illustrated in one proteomic and three microarray experiments. The MRCM facilitates the exploration task involved in ontology analysis on proteomic/genomic experiments, where consensus terms were found to validate main experimental hypothesis. The use of more than one reference may provide new biological insights. The tool automatically highlights non-consensus terms assisting SEA.S
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