567 research outputs found
RNA quantification using gold nanoprobes - application to cancer diagnostics
Molecular nanodiagnostics applied to cancer may provide rapid and sensitive detection of cancer related molecular alterations, which would enable early detection even when those alterations occur only in a small percentage of cells. The use of gold nanoparticles derivatized with thiol modified oligonucleotides (Au-nanoprobes) for the detection of specific nucleic acid targets has been gaining momentum as an alternative to more traditional methodologies. Here, we present an Au-nanoparticles based approach for the molecular recognition and quantification of the BCR-ABL fusion transcript (mRNA), which is responsible for chronic myeloid leukemia (CML), and to the best of our knowledge it is the first time quantification of a specific mRNA directly in cancer cells is reported. This inexpensive and very easy to perform Au-nanoprobe based method allows quantification of unamplified total human RNA and specific detection of the oncogene transcript. The sensitivity settled by the Au-nanoprobes allows differential gene expression from 10 ng/μl of total RNA and takes less than 30 min to complete after total RNA extraction, minimizing RNA degradation. Also, at later stages, accumulation of malignant mutations may lead to resistance to chemotherapy and consequently poor outcome. Such a method, allowing for fast and direct detection and quantification of the chimeric BCR-ABL mRNA, could speed up diagnostics and, if appropriate, revision of therapy. This assay may constitute a promising tool in early diagnosis of CML and could easily be extended to further target genes with proven involvement in cancer development
Relationship between Resilience and Self-regulation: A Study of Spanish Youth at Risk of Social Exclusion
The Supplementary Material for this article can be found online at: http://journal.frontiersin.org/article/10.3389/fpsyg.2017.00612/full#supplementary-materialThe ability to self-regulate behavior is one of the most important protective factors in relation with resilience and should be fostered especially in at-risk youth. Previous research has characterized these students as having behaviors indicating lack of foresight. The aim of the present study was to test the hypothetical relationship between these personal variables. It was hypothesized that self-regulation would be associated with and would be a good predictor of resilience, and that low-medium-high levels of self-regulation would lead to similar levels of resilience. The participants were 365 students -aged 15 and 21- from Navarre (Spain) who were enrolled in Initial Vocational Qualification Programs (IVQP). For the assessment, the Connor Davidson Resilience Scale (CD-RISC) and the Short Self-Regulation Questionnaire (SSRQ) were applied. We carried out linear association analyses (correlational and structural) and non-linear interdependence analyses (MANOVA) between the two constructs. Relationships between them were significant and positive. Learning from mistakes (self-regulation) was a significant predictor of coping and confidence, tenacity and adaptation, and tolerance to negative situations (resilience). Likewise, low-medium-high levels of self-regulation correlated with scores on resilience factors. Implications of these results for educational practice and for future research are discussed.Motivational-affective strategies of personal self-regulation and coping with stress in the university teaching-learning process. Ref. EDU2011-24805 (2012-2015). Ministry of Economy and Competitiveness (Spain) and FEDER Found (EU)
Deciphering intracellular events triggered by mild magnetic hyperthermia in vitro and in vivo
This work is licensed under the Creative Commons Attribution-NonCommercial 3.0 Unported License.-- et al.[Aim]: To assess the cell response to magnetic nanoparticles under an alternating magnetic field by molecular quantification of heat responsive transcripts in two model systems. [Materials & methods]: Melanoma cells and Hydra vulgaris treated with magnetic nanoparticles were subjected to an alternating magnetic field or to macroscopic heating. Effect to these treatments were assessed at animal, cellular and molecular levels. [Results]: By comparing hsp70 expression following both treatments, thermotolerance pathways were found in both systems in absence of cell ablation or global temperature increment. [Conclusion]: Analysis of hsp70 transcriptional activation can be used as molecular thermometer to sense cells' response to magnetic hyperthermia. Similar responses were found in cells and Hydra, suggesting a general mechanism to the delivery of sublethal thermal doses.The authors thank NanoSciEraNet project NANOTRUCK for financial support. JM de la Fuente thanks ERC-Starting Grant 239931-NANOPUZZLE project and Fondo Social Europeo (FSE; Gobierno de Aragón) for financial support.Peer Reviewe
Natural Polysaccharides for siRNA Delivery: Nanocarriers Based on Chitosan, Hyaluronic Acid, and Their Derivatives
Natural polysaccharides are frequently used in the design of drug delivery systems due to their biocompatibility, biodegradability, and low toxicity. Moreover, they are diverse in structure, size, and charge, and their chemical functional groups can be easily modified to match the needs of the final application and mode of administration. This review focuses on polysaccharidic nanocarriers based on chitosan and hyaluronic acid for small interfering RNA (siRNA) delivery, which are highly positively and negatively charged, respectively. The key properties, strengths, and drawbacks of each polysaccharide are discussed. In addition, their use as efficient nanodelivery systems for gene silencing applications is put into context using the most recent examples from the literature. The latest advances in this field illustrate effectively how chitosan and hyaluronic acid can be modified or associated with other molecules in order to overcome their limitations to produce optimized siRNA delivery systems with promising in vitro and in vivo result
Biosensor comprising metal nanoparticles
[ES] La presente invención se refiere a un biosensor
donde la detección del analito se realiza de forma
visual por el cambio de color en las zonas del soporte
en que el analito esté presente producido por las
nanopartículas al ser irradiadas con una fuente de luz
externa[EN] The present invention discloses a biosensor for visual detection of an analyte, based on the light to heat conversion properties of metal nanoparticles: the analyte is visually detected by the colour change in the support areas (where the analyte is present), produced as a result of the heat generated by the metal nanoparticles where they are irradiated with an external light source. Use of said biosensor in a method for the detection of analytes is also claimed.Peer reviewedUniversidad de Zaragoza, Fundación Agencia Aragonesa para la Investigación y el Desarrollo, Consejo Superior de Investigaciones Científicas (España)B1 Patente sin examen previ
A polyoxometalate-assisted approach for synthesis of Pd nanoparticles on graphene nanosheets: synergistic behaviour for enhanced electrocatalytic activity
et al.A polyoxometalate (POM) assisted approach has been employed to prepare a nanohybrid of Pd nanoparticles (PdNPs) and graphene nanosheets (GNSs). The Keggin-type POM, phosphomolybdic acid (PMo12), was applied to serve as both reducing and stabilising agent. The as-prepared nanohybrid (Pd/PMo12/GNSs) was comprehensively characterised using transmission electron microscopy and X-ray diffraction analysis. The synergistic behaviour of PdNPs, PMo12 and GNSs in the nanohybrid leads to elevated electrocatalytic property for ethanol oxidation. Moreover, the Pd/PMo12/GNSs nanohybrid was activated by applying a sufficiently negative potential which plays a key role in promoting the electrocatalytic activity. The activated catalyst presents a superior performance towards ethanol electrooxidation reaction and shows better tolerance to poisoning species compared to Pd and Pt nanoparticles. The outstanding electrocatalytic activity of the tri-component (Pd/PMo12/GNSs) nanohybrid is discussed with relevance to its application in direct alcohol fuel cells (DAFCs).TEM, HAADF-STEM measurements have been performed through part of the fund of the Marie Curie Intra-European Fellowship 328985-COCOPOPS and ERC-Starting Grant 239931-NANOPUZZLE.Peer reviewe
Surfactant-free synthesis and scalable purification of triangular gold nanoprisms with low non-specific cellular uptake
Gold nanoprisms possess remarkable optical properties that make them useful for medical biotechnology applications such as diagnosis and photothermal therapy. However, shape-selective synthesis of gold nanoprisms is not trivial and typically requires either toxic surfactants or time-consuming purification protocols, which can limit their applicability. Here, we show how triangular gold nanoprisms of different sizes can be purified by precipitation using the non-toxic glutathione ligand, thereby removing the need for toxic surfactants and bottleneck purification techniques. The protocol is amenable for direct scaling up as no instrumentation is required in the critical purification step. The new purification method provides a two-fold increased yield in gold nanoprisms compared to electrophoretic filtration, while providing nanoprisms of similar localized surface plasmon resonance wavelength. Crucially, the gold nanoprisms isolated using this methodology show fewer non-specific interactions with cells and lower cellular internalization, which paves the way for a higher selectivity in therapeutic applications
Obtencion de recubrimientos autolubricados por proyeccion termica de plasma atmosferico (APS) como alternativa a los lubricantes liquidos
La obtención de recubrimientos con bajos coeficientes de fricción, es una innovadora respuesta a la creciente demanda industrial de alternativas para los tradicionales sistemas lubricados con aceites. Para este fin, la introducción de un sólido lubricante, en una matriz con buenas propiedades mecánicas, ha de conferir al conjunto un bajo coeficiente de fricción y mejorar la resistencia al desgaste del recubrimiento, favoreciendo además, la utilización a elevadas temperaturas, en las que los lubricantes líquidos convencionales presentan limitaciones. En el Centro de Proyección Térmica (CPT) de la Universidad de Barcelona se han obtenido mediante proyección de Plasma Atmosférico (APS) recubrimientos autolubricados de Ni-Grafito y Cr2O3-CaF2, estudiando con especial interés las propiedades y el efecto que produce el grafito y el CaF2 en las matrices metálica y cerámica respectivamente. Se ha determinado en los dos casos que el desgaste originado en los recubrimientos es bajo, si bien los coeficientes de fricción varían ostensiblemente en función del sistema indicado. Los resultados obtenidos indican que el recubrimiento de Ni-Grafito posee un comportamiento idóneo capaz de competir con los tradicionales lubricantes líquidos
Surface modified Eu:GdVO4 nanocrystals for optical and MRI imaging
A facile solvothermal route has been developed for the preparation of europium doped gadolinium orthovanadate nanoparticles (∼70 nm) with tetragonal structure, based on a homogenous precipitation reaction at 120 °C from rare earth precursors (yttrium nitrate and europium nitrate) and sodium orthovanadate solutions using an ethylene glycol-water mixture as the solvent. The effects of the doping level on the luminescence properties were evaluated in order to find the optimum nanophosphors. These nanocrystals were successfully functionalized with amino (two step process) and carboxylate (one-pot process) groups provided by amino-dextran polymers (AMD) and polyacrylic acid (PAA), respectively. It was found that while the luminescent properties of both kinds of functionalized systems were similar, the colloidal stability of the PAA-modified sample was higher, because of which, it was selected to study their cytotoxicity and magnetic properties (relaxivity and phantom analyses) to assess their potentiality as multifunctional probes for both >in vitro> optical biolabels and negative contrast agents for magnetic resonance imaging. This journal is © The Royal Society of Chemistry 2013.Peer Reviewe
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