134 research outputs found
Diagnóstico de la EPOC
La presencia de síntomas puede ser extremadamente variable en los pacientes con EPOC, y un diagnóstico firme sólo puede ser confirmado objetivando una limitación al flujo aéreo mediante la realización de una espirometría
Real-Time Characterization of Electrospun PVP Nanofibers as Sensitive Layer of a Surface Acoustic Wave Device for Gas Detection
A wireless and portable electronic nose to differentiate musts of different ripeness degree and grape varieties
Two novel applications using a portable and wireless sensor system (e-nose) for the wine producing industry—The recognition and classification of musts coming from different grape ripening times and from different grape varieties—Are reported in this paper. These applications are very interesting because a lot of varieties of grapes produce musts with low and similar aromatic intensities so they are very difficult to distinguish using a sensory panel. Therefore the system could be used to monitor the ripening evolution of the different types of grapes and to assess some useful characteristics, such as the identification of the grape variety origin and to prediction of the wine quality. Ripening grade of collected samples have been also evaluated by classical analytical techniques, measuring physicochemical parameters, such as, pH, Brix, Total Acidity (TA) and Probable Grade Alcoholic (PGA). The measurements were carried out for two different harvests, using different red (Barbera, Petit Verdot, Tempranillo, and Touriga) and white (Malvar, Malvasía, Chenin Blanc, and Sauvignon Blanc) grape musts coming from the experimental cellar of the IMIDRA at Madrid. Principal Component Analysis (PCA) and Probabilistic Neural Networks (PNN) have been used to analyse the obtained data by e-nose. In addition, and the Canonical Correlation Analysis (CCA) method has been carried out to correlate the results obtained by both technologies. © 2015 by the authors; licensee MDPI, Basel, Switzerland.This work is being supported by the Instituto Nacional de Investigación y Tecnología
Agraria y Alimentaria (INIA) of the Economía y Competitividad Ministry, under the project
RTA2011-00095-C02-02. We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).Peer Reviewe
Nanocrystalline tin oxide nanofibers deposited by a novel focused electrospinning method. Application to the detection of TATP precursors
A new method of depositing tin dioxide nanofibers in order to develop chemical sensors is presented. It involves an electrospinning process with in-plane electrostatic focusing over micromechanized substrates. It is a fast and reproducible method. After an annealing process, which can be performed by the substrate heaters, it is observed that the fibers are intertwined forming porous networks that are randomly distributed on the substrate. The fiber diameters oscillate from 100 nm to 200 nm and fiber lengths reach several tens of microns. Each fiber has a polycrystalline structure with multiple nano-grains. The sensors have been tested for the detection of acetone and hydrogen peroxide (precursors of the explosive triacetone triperoxide, TATP) in air in the ppm range. High and fast responses to these gases have been obtained. © 2014 by the authors; licensee MDPI, Basel, Switzerland.This work has been supported by the Spanish Science and Innovation Ministry under the
projects TEC2010-21357-C05-04 and TEC2013-48147-C6-4-R. Authors want to thank University of
Extremadura for SEM and XRD analysis. We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI)Peer Reviewe
Love-Wave Sensors Combined with Microfluidics for Fast Detection of Biological Warfare Agents
The following paper examines a time-efficient method for detecting biological warfare agents (BWAs). The method is based on a system of a Love-wave immunosensor combined with a microfluidic chip which detects BWA samples in a dynamic mode. In this way a continuous flow-through of the sample is created, promoting the reaction between antigen and antibody and allowing a fast detection of the BWAs. In order to prove this method, static and dynamic modes have been simulated and different concentrations of BWA simulants have been tested with two immunoreactions: phage M13 has been detected using the mouse monoclonal antibody anti-M13 (AM13), and the rabbit immunoglobulin (Rabbit IgG) has been detected using the polyclonal antibody goat anti-rabbit (GAR). Finally, different concentrations of each BWA simulants have been detected with a fast response time and a desirable level of discrimination among them has been achieved.This work was supported by the Spanish Science and Innovation Ministry under the project
TEC2010-21357-C05-04, and a postdoctoral fellowship at the National Autonomous University
of Mexico.We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI)Peer reviewe
Angioedema severity and impact on quality of life: Chronic histaminergic angioedema versus chronic spontaneous urticaria
Histamine-mediated angioedema is the most frequent form of angioedema. It is classified as idiopathic histaminergic acquired angioedema (IH-AAE)1 when allergies and other causes have been excluded and a positive treatment response to antihistamines, corticosteroids, or omalizumab has been reported. Idiopathic histaminergic acquired angioedema may occur in isolation, when it is termed chronic histaminergic angioedema (CHA), or it may be associated with wheals in chronic spontaneous urticaria angioedema (CSU-AE). The term CHA is equivalent to IH-AAE and mast cell-mediated angioedema. However, this term reflects the chronic and recurrent course of the disease. Therefore, we propose that the term CHA be internationally discussed in the following guidelines. Chronic spontaneous urticaria is classically characterized by the presence of recurrent episodes of wheals (hives) with or without angioedema for at least 6 weeks.2 Chronic histaminergic angioedema is typically considered a subtype of CSU without wheals. However, a recent study3 found several features that differentiate CHA from CSU, which suggests that CHA is a separate entity. Quality of life (QoL) studies specifically for CHA patients have not been performed, and their QoL has been assessed only in the context of CSU-AE
Carbon nanotube networks as gas sensors for NO2 detection
Networks of different carbon nanotube (CNT) materials were investigated as resistive gas sensors for NO2 detection. Sensor films were fabricated by airbrushing dispersions of double-walled and multi-walled CNTs (DWNTs and MWNTs, respectively) on alumina substrates. Sensors were characterized by resistance measurements from 25 to 250 °C in air atmosphere in order to find the optimum detection temperature. Our results indicate that CNT networks were sensitive to NO2 concentrations as low as 0.1 ppm. All tested sensors provided significantly lower response to interfering gases such as H2, NH3, toluene and octane. We demonstrate that the measured sensitivity upon exposure to NO2 strongly depends on the employed CNT material. The highest sensitivity values were obtained at temperatures ranging between 100 and 200 °C. The best sensor performance, in terms of recovery time, was however achieved at 250 °C. Issues related to the gas detection mechanisms, as well as to CNT network thermal stability in detection experiments performed in air at high operation temperatures are also discussed.This work has been supported by MEC (Spain, projects TEC2004-05098-C02-01/MIC and TEC2004-05098-C02-02/MIC, Programa I3 2006 8 0I 060) and the European Regional Development Fund (ERDF).Peer reviewe
Novel selective sensors based on carbon nanotube films for hydrogen detection
Novel resistive gas sensors based on single-walled carbon nanotubes (SWNTs) as an active sensing element have been evaluated for hydrogen detection. Sensor films were fabricated by airbrushing SWNT dispersions on alumina substrates. The employed SWNT materials were either chemically functionalized with Pd or sputtered with Pd to enhance their sensitivity to hydrogen. Sensors were characterized by dc electrical measurements in nitrogen and air atmosphere. The response to hydrogen and the cross sensitivity to gases such as ammonia, toluene and octane were studied. Aged Pd-functionalized SWNT films exhibited good sensitivity and selectivity to hydrogen at room temperature. The effect of aging, thermal treatments and the employed carrier gas were also investigated.This work is been supported by MEC (Spain, Projects TEC2004-05098-C02-01/MIC and TEC2004-05098-C02-02/MIC). The authors wish to thank Christine Würzburger of Heraeus S.A. for kindly providing the Heraeus MSP 769 substrates.Peer reviewe
Cancer Genes Hypermethylated in Human Embryonic Stem Cells
Developmental genes are silenced in embryonic stem cells by a bivalent histone-based chromatin mark. It has been proposed that this mark also confers a predisposition to aberrant DNA promoter hypermethylation of tumor suppressor genes (TSGs) in cancer. We report here that silencing of a significant proportion of these TSGs in human embryonic and adult stem cells is associated with promoter DNA hypermethylation. Our results indicate a role for DNA methylation in the control of gene expression in human stem cells and suggest that, for genes repressed by promoter hypermethylation in stem cells in vivo, the aberrant process in cancer could be understood as a defect in establishing an unmethylated promoter during differentiation, rather than as an anomalous process of de novo hypermethylation
Effects of Albumin Treatment on Systemic and Portal Hemodynamics and Systemic Inflammation in Patients With Decompensated Cirrhosis
BACKGROUND & AIMS: We investigated the effect of albumin treatment (20% solution) on hypoalbuminemia, cardiocirculatory dysfunction, portal hypertension, and systemic inflammation in patients with decompensated cirrhosis with and without bacterial infections. METHODS: We performed a prospective study to assess the effects of long-term (12 weeks) treatment with low doses of albumin (1 g/kg body weight every 2 weeks), and high doses (1.5 g/kg every week), on serum albumin, plasma renin, cardiocirculatory function, portal pressure, and plasma levels of cytokines, collecting data from 18 patients without bacterial infections (the Pilot-PRECIOSA study). We also assessed the effect of short-term (1 week) treatment with antibiotics alone vs. the combination of albumin plus antibiotics (1.5 g/kg on day 1 and 1 g/kg at day 3) on plasma levels of cytokines in biobanked samples from 78 patients with bacterial infections included in a randomized controlled trial (INFECIR-2 study). RESULTS: Circulatory dysfunction and systemic inflammation were extremely unstable in many patients included in the pilot-PRECIOSA study; these patients had intense and reversible peaks in plasma levels of renin and interleukin 6 (IL6). Long-term high-dose albumin but not low-dose albumin was associated with normalization of serum level of albumin, improved stability of the circulation and left ventricular function, and reduced plasma levels of cytokines (IL6, GCSF, IL1RN, and VEGF) without significant changes in portal pressure. The immune-modulatory effects of albumin observed in the Pilot-PRECIOSA study were confirmed in the INFECIR-2 study. In this study, patients given albumin had significant reductions in plasma levels of cytokines. CONCLUSIONS: In an analysis of data from 2 trials (pilot-PRECIOSA study and INFECIR-2 study) we found that albumin treatment reduces systemic inflammation and cardiocirculatory dysfunction in patients with decompensated cirrhosis. These effects might be responsible for the beneficial effects of albumin therapy on outcomes of patients with decompensated cirrhosis. ClinicalTrials.gov no: NCT00968695 and NCT03451292
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