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Ketone bodies (KBs), especially ß-hydroxybutyrate (BHB), have gained tremendous attention as potential biomarkers as their presence in bodily fluids is closely associated with health and wellness. While a variety of blood fingerstick test strips are available for self-testing of BHB, there are major needs for wearable devices capable of continuously tracking changing BHB concentrations. To address these needs, we present here the first demonstration of a wearable microneedle-based continuous ketone monitoring (CKM) in human interstitial fluid (ISF) and illustrate its ability to closely follow the intake of ketone drinks. To ensure highly stable and selective continuous detection of ISF BHB, the new enzymatic microneedle BHB sensor relies on a gold-coated platinum working electrode modified with a reagent layer containing toluidine blue O (TBO) redox mediator, ß-hydroxybutyrate dehydrogenase (HBD) enzyme, a nicotinamide adenine dinucleotide (NAD+) cofactor, along with carbon nanotubes (CNTs), chitosan (Chit), and a poly(vinyl chloride) (PVC) outer protective layer. The skin-worn microneedle sensing device operates with a miniaturized electrochemical analyzer connected wirelessly to a mobile electronic device for capturing, processing, and displaying the data. Cytotoxicity and skin penetration studies indicate the absence of potential harmful effects. A pilot study involving multiple human subjects evaluated continuous BHB monitoring in human ISF, against gold standard BHB meter measurements, revealing the close correlation between the two methods. Such microneedle-based CKM offers considerable promise for dynamic BHB tracking toward the management of diabetic ketoacidosis and personal nutrition and wellness.
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Nanotubos de Carbono , Dispositivos Electrónicos Vestibles , Humanos , Cetonas , Proyectos Piloto , Cuerpos Cetónicos , Ácido 3-HidroxibutíricoRESUMEN
The biggest allure of heterogeneous electro-Fenton (HEF) processes largely fails on its high efficiency for the degradation of a plethora of hazardous compounds present in water, but still challenging to search for good and cost-effective electrocatalyst. In this work, carbon black (CB) and oxidised carbon black (CBox) materials were investigated as cathodes in the electrochemical production of hydrogen peroxide involved in HEF reaction for the degradation of 2-phenylphenol (2PP) as a target pollutant. The electrodes were fabricated by employing carbon cloth as support, and the highest H2O2 production yields were obtained for the CBox, pointing out the beneficial effect of the hydrophilic character of the electrode and oxygen-type functionalization of the carbonaceous surface. HEF degradation of 2PP was explored at -0.7 V vs. Ag/AgCl exhibiting the best conversion rates and degradation grade (total organic carbon) for the CBox-based cathode. In addition, the incorporation of an electrochemical sensor of 2PP in line with the HEF reactor was accomplished by the use of screen-printed electrodes (SPE) in order to monitor the pollutant degradation. The electrochemical sensor performance was evaluated from the oxidation of 2PP in the presence of Fe2+ ions by using square wave voltammetry (SWV) technique. The best electrochemical sensor performance was based on SPE modified with Meldola Blue showing a high sensitivity, low detection limit (0.12 ppm) and wide linear range (0.5-21 ppm) with good reproducibility (RSD 2.3 %). The all-in-one electrochemical station has been successfully tested for the degradation and quantification of 2PP, obtaining good recoveries analysing spiked waters from different water matrices origins.
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Microneedle sensor technology offers exciting opportunities for decentralized clinical analyses. A novel issue puts forward herein is to demonstrate the uniqueness of membrane-based microneedles to accomplish real-time, on-body monitoring of multiple ions simultaneously. The use of multi-ion detection is clinically relevant since it is expected to provide a more complete and reliable assessment of the clinical status of a subject concerning electrolyte disorders and others. We present a microneedle system for transdermal multiplexed tracing of pH, Na+, K+, Ca2+, Li+, and Cl-. The device consists of an array of seven solid microneedles externally modified to provide six indicator electrodes, each selective for a different ion, and a common reference electrode, all integrated into a wearable patch read in a potentiometric mode. We show in vitro measurements at the expected clinical levels, resulting in a fast response time, excellent reversibility and repeatability, and adequate selectivity. Close-to-Nernstian sensitivity, sufficient stability and resiliency to skin penetration guarantee the sensor's success in transdermal measurements, which we demonstrate through ex vivo (with pieces of rat skin) and in vivo (on-body measurements in rats) tests. Accuracy is evaluated by comparison with gold standard techniques to characterize collected dermal fluid, blood, and serum. In the past, interstitial fluid (ISF) analysis has been challenging due to difficult sample collection and analysis. For ions, this has resulted in extrapolations from blood concentrations (invasive tests) rather than pure measurements in ISF. The developed microneedle patch is a relevant analytical tool to address this information gap.
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Agujas , Piel , Ratas , Animales , Potenciometría , Electrodos , IonesRESUMEN
Glycine (GLY) is gaining importance in medical diagnoses due to its relationship with multiple physiological functions. Today, GLY is exclusively analyzed using instrumentation centralized in clinical labs, and a tangible point-of-care tool that gathers real-time data from the patient for effective and fast evaluations is lacking. Relevant clinical advances are expected as soon as the rapid provision of both punctual and continuous measurements is possible. In that context, this work presents a microneedle (MN)-based biosensor for intradermal GLY detection in interstitial fluid (ISF). The MN tip is externally tailored to detect GLY levels through the hydrogen peroxide formed in its reaction with a quinoprotein-based GLY oxidase enzyme. The analytical performance of the MN biosensor indicates a fast response time (<7 s); acceptable reversibility, reproducibility, and stability; as well as a wide linear range of response (25-600 µM) that covers the physiological levels of GLY in ISF. The MN biosensor conveniently exhibits high selectivity for GLY over other compounds commonly found in ISF, and the response is not influenced by temperature, pH, or skin insertions. Validated intradermal measurements of GLY were obtained at the in vitro (with pieces of rat skin), ex vivo (on-body tests of euthanized rats) and in vivo (on-body tests of anesthetized rats) levels, demonstrating its ability to produce accurate physiological data. The developed GLY MN biosensor is skin-wearable and provides reliable, real-time intradermal GLY measurements in ISF by means of a minimally invasive approach.
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Técnicas Biosensibles , Dispositivos Electrónicos Vestibles , Animales , Glicina , Agujas , Ratas , Reproducibilidad de los ResultadosRESUMEN
Electrochemical (bio)sensors are considered clean and powerful analytical tools capable of converting an electrochemical reaction between analytes and electrodes into a quantitative signal. They are an important part of our daily lives integrated in various fields such as healthcare, food and environmental monitoring. Several strategies including the incorporation of porous carbon materials in its configuration have been applied to improve their sensitivity and selectivity in the last decade. The porosity, surface area, graphitic structure as well as chemical composition of materials greatly influence the electrochemical performance of the sensors. In this review, activated carbons, ordered mesoporous carbons, graphene-based materials, and MOF-derived carbons, which are used to date as crucial elements of electrochemical devices, are described, starting from their textural and chemical compositions to their role in the outcome of electrochemical sensors. Several relevant and meaningful examples about material synthesis, sensor fabrication and applications are illustrated and described. The closer perspectives of these fascinating materials forecast a promising future for the electrochemical sensing field.
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Técnicas Electroquímicas , Grafito , Electrodos , Grafito/química , PorosidadRESUMEN
In this work, we present a new catechol amperometric biosensor fabricated on the basis of naturally available enzymes in common mushrooms. The biosensor response mechanism comprises the reduction of the quinone exclusively produced in the oxidation of the catechol present in the sample, which is catalyzed by tyrosinase enzyme. The new catechol biosensor has demonstrated excellent analytical performance at increasing catechol concentrations in the sample solution, which includes superior reproducibility for several electrodes and long-term stability. On top of that, the biosensing element used in the fabrication is a sustainable material, of low-cost and presents an excellent lifetime of years. Whether the catechol biosensor is operating in the presence of a compound influencing the reactions underlying the amperometric response (such as ascorbic, benzoic, gallic and kojic acids), this serves as an analytical platform to detect these compounds in real samples. Particularly, we introduce herein for the first time different treatments to process the current signal of the biosensor pursuing the linearity needed for the analytical application in real samples. In this sense, the catechol biosensor has been successfully applied to the detection of benzoic, gallic and kojic acids in juices, teas and cosmetic products, respectively.
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Ácido Ascórbico/análisis , Ácido Benzoico/análisis , Técnicas Biosensibles/métodos , Catecoles/química , Ácido Gálico/análisis , Pironas/análisis , Agaricales/enzimología , Ácido Ascórbico/química , Ácido Benzoico/química , Catecoles/metabolismo , Electroquímica , Ácido Gálico/química , Monofenol Monooxigenasa/metabolismo , Pironas/químicaRESUMEN
This work investigates the impact of carbon black (CB) as a porogenic agent and conductive additive in the preparation of electrically conductive nanoporous carbon gels. For this, a series of materials were prepared by the polycondensation of resorcinol/formaldehyde mixtures in the presence of increasing amounts of carbon black. The conductivity of the carbon gel/CB composites increased considerably with the amount of CB, indicating a good dispersion of the additive within the carbon matrix. A percolation threshold of ca. 8 wt.% of conductive additive was found to achieve an adequate "point to point" conductive network. This value is higher than that reported for other additives, owing to the synthetic route chosen, as the additive was incorporated in the reactant's mixture (pre-synthesis) rather than in the formulation of the electrodes ink (post-synthesis). The CB strongly influenced the development of the porous architecture of the gels that exhibited a multimodal mesopore structure comprised of two distinct pore networks. The microporosity and the primary mesopore structure remained rather unchanged. On the contrary, a secondary network of mesopores was formed in the presence of the additive. Furthermore, the average mesopore size and the volume of the secondary network increased with the amount of CB.
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Resumen El objetivo del trabajo realizado fue conocer la percepción de los directivos de los programas de Atención Domiciliaria (A.D), sobre el modelo que desarrollan como alternativa asistencial, así mismo analizar cómo se constituye la estructura del cuidado desde la perspectiva de las instituciones prestadoras de este servicio en el Departamento del Meta. El estudio fue cualitativo, descriptivo con enfoque fenomenológico, la población estuvo constituida por directivos de 8 programas de A.D existentes en los municipios de mayor desarrollo socioeconómico de la región. La información se obtuvo a través de entrevistas y narrativas, analizadas con la herramienta informática NVivo 10, la cual permitió la organización, análisis de la información y la interpretación de resultados a partir de la agrupación de temas centrales. Los resultados permitieron identificar tres categorías de análisis: Calidad y satisfacción del usuario, integralidad de la atención y Autocuidado como base del crecimiento personal. Se pudo concluir que la percepción encontrada en los directivos, está fundamentada en una intencionalidad que favorece el desarrollo de un modelo de atención integral participativo, que facilita el crecimiento personal, el fortalecimiento del autocuidado y el empoderamiento de los usuarios para acompañar diferentes situaciones de salud en el ámbito domiciliario.
Abstract The aim of the work was to study the perceptions of managers of programs of home care (A.D), on the model developed as alternative care, also analyze how is the structure of care from the perspective of institutions providing this service in the Department of Meta. The study was descriptive, qualitative phenomenological approach, the population consisted of Directors of 8 A.D existing programmes in the municipalities of greater socio-economic development of the region. The information was obtained through interviews and narratives, analyzed with NVivo 10 computer tool, which allowed the Organization, analysis of the information and the interpretation of results from the grouping of central themes. The results helped identify three categories of analysis: quality and user satisfaction, integrality of care and self-care as a basis for personal growth. One could conclude that perception found in the executives, is based on the intention that favours the development of a participatory model of comprehensive care that facilitates personal growth, the strengthening of self-care and the empowerment of users to accompany different situations of health at the home.
Resumo O objetivo do trabalho foi estudar a percepção dos gestores de programas de atendimento domiciliar (AD), o modelo desenvolvido como alternativa de cuidados, também analisar como é a estrutura de atendimento da perspectiva de instituições oferecendo esse serviço no departamento de Meta. O estudo foi descritiva, qualitativa de abordagem fenomenológica, a população era formada por diretores de Adriano 8 programas existentes nos municípios de maior desenvolvimento sócio-económico da região. As informações foram obtidas através de entrevistas e narrativas, analisadas com NVivo 10 ferramenta de computador, que permitiu a organização, análise da informação e a interpretação dos resultados do agrupamento de temas centrais. Os resultados ajudaram a identificar três categorias de análise: qualidade e satisfação dos utilizadores, a integralidade do cuidado e auto-cuidado como base para o crescimento pessoal. Se poderia concluir que percepção encontrada nos executivos, baseia-se sobre a intenção que favorece o desenvolvimento de um modelo participativo de atenção integral que facilita o crescimento pessoal, o reforço de auto-cuidado e a empoderamento dos usuários para acompanhar as diferentes situações de saúde em casa.
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UNLABELLED: In Spain syphilis shows an increasing trend from last decade and multiple papers reported an increasing of exposed population. Our aim was to describe the evolution of the incident of the syphilis in the geographical frame of the city of Valencia, to identify the characteristics and practices of risk of the affected ones. A classic design of vigilance of public health was applied, longitudinal retrospective study. Geographical area: the city of Valencia. PERIOD: January 2003-December 2014. VARIABLES: age and sex, national origin, dates of access to the sanitary system, date of diagnosis, clinical forms of presentation, conducts of risk, and practices of risk. The annual impact of the disease evolved from 2.4 × 10(5) in 2004 up to 14.5 × 10(5) in 2014. Males (82.96%) masculinity rate: 4.8. Major specific incidence took places on age-groups 35-39 years with 16.49 × 10(5) and 40-44 years with 16.98 × 10(5). The difference between women stands out according to origin: middle ages in autochthonous (39.72 years) opposite to foreigners (32.91 years); P = .004. The primary forms were 5 times more probable in males. The major factor of risk was to have multiple couples (54.89%), man-to-man homo or bisexuals reaches 90.0% of it. The HIV (human immunodeficiency virus) infection was 29.07% in males and 4.35% in women. Precedent of multiple couple relations would not be a minor of 42 times more likely among the homosexual population with syphilis. Major determinant of risk were the relations with multiple pairs and the prevention will have to be focused to the group of men who practice sex with men.
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Vigilancia de la Población , Sífilis/epidemiología , Femenino , Infecciones por VIH/epidemiología , Homosexualidad Masculina , Humanos , Incidencia , Masculino , Estudios Retrospectivos , Distribución por Sexo , España/epidemiología , Sífilis/transmisiónRESUMEN
The objective of this study was to analyse whether variables associated with emergency services (ES) use in Spain have changed in the period 2006-2011 using a comparative analysis of the 2006 and 2011 Spanish National Health Surveys. The measure of association was the prevalence ratio with its 95% confidence interval, obtained by Poisson regression with robust variance. We studied interactions between the explanatory variables for ES use and year and subsequently performed a stratified analysis by year. ES use declined by 2.1% in 2011. Most emergency care (approximately 60% in both surveys) was provided in public hospitals. Between 2006 and 2011, ES use increased by 9% in women (p for interaction = 0.008) [ref. men], 3% in persons with poor mental health (p for interaction = 0.072) [ref. good mental health], and 8% in individuals with limitations on activities of daily living (p for interaction = 0.006) [ref. no limitations]. The change in the effect of the variables sex, mental health, and limitations on activities of daily living on use of ES (2006 and 2011) is not explained by either demographic characteristics or individual socioeconomic indicators. These results could be associated with macroeconomic and structural changes occurring during the period 2006-2011.
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Recesión Económica , Servicios Médicos de Urgencia/estadística & datos numéricos , Estado de Salud , Adolescente , Adulto , Anciano , Estudios Transversales , Servicios Médicos de Urgencia/tendencias , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Factores Socioeconómicos , España/epidemiología , Encuestas y Cuestionarios , Desempleo , Adulto JovenRESUMEN
UVB irradiation of epidermal keratinocytes results in the activation of the p38 mitogen-activated protein kinase (MAPK) pathway and subsequently activator protein-1 (AP-1) transcription factor activation and cyclooxygenase-2 (COX-2) expression. AP-1 and COX-2 have been shown to play functional roles in UVB-induced mouse skin carcinogenesis. In this study, the experimental approach was to express a dominant negative p38α MAPK (p38DN) in the epidermis of SKH-1 hairless mice and assess UVB-induced AP-1 activation, COX-2 expression, and the skin carcinogenesis response in these mice compared to wild-type littermates. We observed a significant inhibition of UVB-induced AP-1 activation and COX-2 expression in p38DN transgenic mice, leading to a significant reduction of UVB-induced tumor number and growth compared to wild-type littermates in a chronic UVB skin carcinogenesis model. A potential mechanism for this reduction in tumor number and growth rate is an inhibition of chronic epidermal proliferation, observed as reduced Ki-67 staining in p38DN mice compared to wild-type. Although we detected no difference in chronic apoptotic rates between transgenic and nontransgenic mice, analysis of acutely irradiated mice demonstrated that expression of the p38DN transgene significantly inhibited UVB-induced apoptosis of keratinocytes. These results counter the concerns that inhibition of p38 MAPK in a chronic situation could compromise the ability of the skin to eliminate potentially tumorigenic cells. Our data indicate that p38 MAPK is a good target for pharmacological intervention for UV-induced skin cancer in patients with sun damaged skin, and suggest that inhibition of p38 signaling reduces skin carcinogenesis by inhibiting COX-2 expression and proliferation of UVB-irradiated cells.
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Epidermis/metabolismo , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Rayos Ultravioleta/efectos adversos , Proteínas Quinasas p38 Activadas por Mitógenos/fisiología , Animales , Apoptosis/efectos de la radiación , Western Blotting , Proliferación Celular/efectos de la radiación , Ciclooxigenasa 2/fisiología , Progresión de la Enfermedad , Epidermis/patología , Epidermis/efectos de la radiación , Femenino , Genes Dominantes , Humanos , Técnicas para Inmunoenzimas , Luciferasas/metabolismo , Ratones , Ratones Pelados , Ratones Transgénicos , Neoplasias Cutáneas/etiologíaRESUMEN
El método de fusión de protoplastos fue usado para la obtención de recombinantes con producción antibiótica incrementada en Streptomyces erythreus productora de eritromicina. Se emplearon los mutantes morfológicos 36 UV y P-E obtenidos por luz UV y luz UV-acriflavina respectivamente, los cuales poseían marcadores de resistencia a cloranfenicol y rifampicina. Se establecen las condiciones más apropiadas para la obtención y fusión de protoplastos en estas cepas, llegándose a obtener recombinantes resistentes a ambos antibióticos a frecuencia de 0,57 %, dentro de las cuales fue seleccionado uno con incremento de 4 veces en la producción de eritromicina
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Eritromicina/biosíntesis , Protoplastos/metabolismo , Streptomyces antibioticus/metabolismoRESUMEN
Se establecen las condiciones necesarias para la formación de protoplastos en Streptomyces erythreus con el uso del tratamiento enzimático con lisozima, además del medio específico y de las condiciones más efectivas para la regeneración de los mismos
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Eritromicina/biosíntesis , Muramidasa/farmacología , Protoplastos , Streptomyces/enzimologíaRESUMEN
Se aíslan 6 mutantes auxotróficos por la técnica de plaqueo por réplica después de la mutagénesis con luz ultravioleta (UV). Se señala que en la caracterización todos resultaron alterados en la vía de síntesis de la arginina. Se aíslan 4 revertantes espontáneos de 3 de los mutantes. Se informa que la aplicación del método de Kelner de difusión en agar para determinar la producción antibiótica a mutantes y revertantes y el procesamiento estadístico de los resultados obtenidos, evidenció que no existen diferencias significativas entre la cepa parental y los mutantes, pero sí entre la cepa parental y los revertantes, y produce uno de ellos, el 28-2, significativamente menos que la cepa RA-2. Se indica que el cálculo del coeficiente de variación para los mutantes evidenció una mayor estabilidad de los mutantes 20, 25, 26, y 28 en relación con la cepa parental, y el 25 es 5 veces más estable que éste