713 research outputs found

    Performance Analysis of an Annular Diffuser Under the Influence of a Gas Turbine Stage Exit Flow

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    In this investigation the performance of a gas turbine exhaust diffuser subject to the outlet flow conditions of a turbine stage is evaluated. Towards that goal, a fully three-dimensional computational analysis has been performed where several turbine stage-exhaust diffuser configurations have been studied: a turbine stage with a shrouded rotor coupled to a diffuser with increasing divergence angle in the diffuser, and a turbine stage with an unshrouded rotor was also considered for the exhaust diffuser performance analysis. The large load of this investigation was evaluated using a steady state numerical analysis utilizing the "mixing plane" algorithm between the rotating rotor and stationary stator and diffuser rows. Finally, an unsteady analysis is performed on a turbine stage with an unsrhouded rotor coupled to an annular exhaust diffuser with an outer wall opening angle of 18°. It has been found that the over the tip leakage flow in the unshrouded rotor emerges as a swirling wall jet at the upper wall of the diffuser. When using the turbine with the shrouded rotor no wall jet was observed, making the flow at the entrance to the diffuser "quasi-uniform". The maximum opening angle of the diffuser upper wall achieved before the diffuser stalls was 12° with a static pressure recovery coefficient of Cp = 0.293. When the wall jet was observed, diffuser opening angles of 18° were possible with a static pressure recovery of Cp = 0.365. Consequently the wall jet energizes the diffuser upper wall boundary layer flow, allows for higher static pressure recovery levels and postpones diffuser stall. By altering the speed of the rotor the effect of the swirl in the turbine exit plane on the performance of the diffuser was explored. In the case where the wall jet was absent the diffuser recovers more pressure when the inlet is swirl-free. In this case the performance of the diffuser is independent on whether the turbine exit flow has co or counter swirl. In the presence of the wall jet, higher static pressure recovery was achieved when the wall jet was in co-swirl and the core flow at a slightly counter-swirl direction. This observation was more pronounced when larger diffuser upper wall opening angles were considered. In the unsteady analysis it was found that the wall jet axial velocity and swirl intensities pulsate with the relative position of the rotor to the stator. The wall jet is always co-swirling while the core flow is counter-swirling. Moreover, the wall jet does not penetrate the diffuser boundary layer as deeply as was observed in the steady state case and flow separation occurs at the upper endwall corner of the diffuser. Furthermore the performance of the diffuser shows a periodic variation that seems to depend on the relative position of the rotor to the stator. The averaged pressure recovery coefficient is Cp = 0.321 which is 11.0 % less than predicted in the steady state case

    Evaluation of a strategy to shorten the time to surgery in patients on antiplatelet therapy with a proximal femur fracture (AFFEcT Study): Study protocol for a multicenter randomized controlled clinical trial

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    Femur fracture; Platelet aggregation inhibitors; Clinical protocolFactura de fèmur; Inhibidors de l'agregació plaquetària; Protocol d'assaig clínicFactura de fémur; Inhibidores de la agregación plaquetaria; Protocolo de ensayo clínicoINTRODUCTION: Patients with femur fracture benefit from early surgery. Recent reports suggest that regional anesthesia may be superior to general anesthesia in these patients. Early surgery under spinal anesthesia could be performed safely by determining platelet function in patients receiving antiplatelet agents. METHODS: Multicenter, randomized, open-label, parallel clinical trial expected to include 156 patients ≥ 18 years of age under chronic treatment with antiplatelet agents who develop a proximal femur fracture. EXCLUSION CRITERIA: presence of multiple or pathological fractures, current treatment with vitamin K antagonists or new oral anticoagulants, and congenital or acquired coagulopathy.Patients will be randomized to eitherThe primary endpoint is time (hours) from admission to surgery. Secondary endpoints include: platelet function; postoperative bleeding; medical-surgical complications; perioperative and 1-year mortality; quality of life; length of hospital stay; cost-effectiveness; and cost-utility. Follow-up assessments will be performed during hospital admission and at 1, 6, and 12 months after surgery. POTENTIAL IMPACT OF THE STUDY: The determination of platelet function at admission to the emergency department in patients with femoral fracture receiving antiplatelet therapy may permit earlier surgery under spinal anesthesia, thus shortening the hospital stay and reducing the risk of complications. These advantages associated with early surgery could positively impact patient well-being and also reduce treatment-related healthcare costs. ETHICS AND DISSEMINATION: The study has been approved by the ethics committees at all participating centers. Their results will be disseminated in congresses and published in peer reviewed journals

    The influence of CYP enzymes and ABCB1 on treatment outcomes in schizophrenia: association of CYP1A2 activity with adverse effects

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    Aim: Genetic variants on metabolic and transport enzymes are good candidates to explain inter-individual differences in response to antipsychotics. The aim of this study is to evaluate and compare the influence of the CYP2D6, CYPC19, CYP1A2 and ABCB1 variants on plasma levels, treatment response and side effects of antipsychotics. Methods: Twenty polymorphisms in selected genes were genotyped in 318 patients diagnosed with schizophrenia, schizoaffective or delusional disorder treated with antipsychotics (clozapine, olanzapine, paliperidone, risperidone, aripiprazole and quetiapine). Plasma drug levels were determined after 6 weeks of treatment. The Positive and Negative Symptoms Scale (PANSS) and UKU scale of side effects were recorded at baseline and after 12 weeks of treatment. The effect of gene variants on plasma drug levels, treatment response and adverse effects were examined by multinomial regression. Results:CYP1A2 was found to be associated with psychic side effects (P = 0.02), with variants predicting higher enzyme activity associated with lower adverse effects, and was the strongest predictor for this adverse effect of all the studied factors. Functional variants in CYP genes were associated with plasma level differences, with higher activity variants associated with lower plasma levels. No association with improvement of the condition, as measured by the PANSS score, was found in this study. Conclusion: The results suggest that increased CYP1A2 activity protects against psychic side effects. Few studies have evaluated the impact of genetic factors on treatment response or side effects, and only in relation to a selection of adverse reactions. These results are a step towards better understanding of the factors behind the different aspects of clinical outcomes, such as various adverse effects

    A pharmacogenetic intervention for the improvement of the safety profile of antipsychotic treatments

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    Antipsychotic drugs fail to achieve adequate response in 30-50% of treated patients and about 50% of them develop severe and lasting side effects. Treatment failure results in poorer prognosis with devastating repercussions for the patients, carers and broader society. Our study evaluated the clinical benefits of a pharmacogenetic intervention for the personalisation of antipsychotic treatment. Pharmacogenetic information in key CYP polymorphisms was used to adjust clinical doses in a group of patients who started or switched treatment with antipsychotic drugs (PharmG+, N = 123), and their results were compared with those of a group of patients treated following existing clinical guides (PharmG−, N = 167). There was no evidence of significant differences in side effects between the two arms. Although patients who had their antipsychotic dose adjusted according to CYPs polymorphisms (PharmG+) had a bigger reduction in side effects than those treated as usual (PharmG−), the difference was not statistically significant (p > 0.05 for all comparisons). However, PharmG+ patients treated with CYP2D6 substrates that were carriers of CYP2D6 UMs or PMs variants showed a significantly higher improvement in global, psychic and other UKU side effects than PharmG− patients (p = 0.02, p = 0.05 and p = 0.01, respectively). PharmG+ clozapine treated patients with CYP1A2 or CYP2C19 UM and PMs variants also showed higher reductions in UKU scores than PharmG− clozapine patients in general. However, those differences were not statistically significant. Pharmacogenetic interventions may improve the safety of antipsychotic treatments by reducing associated side effects. This intervention may be particularly useful when considering treatment with antipsychotics with one major metabolic pathway, and therefore more susceptible to be affected by functional variants of CYP enzymes

    Antibióticos empíricos para la neumonía adquirida en la comunidad en pacientes adultos: Una revisión sistemática y un metaanálisis en red

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    Objetivo: El objetivo principal de este metaanálisis en red es identificar el antibiótico empírico (Em-ATB) con mayor probabilidad de ser el mejor (HPBB) en términos de (1) tasa de curación y (2) tasa de mortalidad en pacientes hospitalizados con neumonía adquirida en la comunidad (NAC) . Método: Criterios de inclusión: (1) pacientes adultos (>16 años) diagnosticados de NAC que requirieron hospitalización; (2) aleatorizados a al menos dos Em-ATB diferentes, (3) que informen de la tasa de curación y (4) que estén escritos en inglés o español. Criterios de exclusión: (1) protocolo de antibióticos ambiguo y (2) publicados exclusivamente en formato resumen o carta. Fuentes de datos: Medline, Embase, Cochrane y revisiones de citas desde el 1 de enero de 2000 hasta el 31 de diciembre de 2018. Riesgo de sesgo: Herramienta de Cochrane. Calidad de la revisión sistemática (RS): A MeaSurement Tool to Assess systematic Reviews-2. Certeza de la evidencia: Grading of Recommendations Assessment, Development and Evaluation. Análisis estadísticos: método frecuentista realizado con la biblioteca 'netmeta', paquete R. Resultados: se incluyeron 27 ensayos controlados aleatorizados (ECA) de las 41.307 citas seleccionadas inicialmente. En cuanto al riesgo de sesgo, más de una cuarta parte de los estudios presentaron riesgo bajo y ningún estudio presentó riesgo alto en todos los dominios. La calidad de la RS es moderada. Para la curación, se construyeron dos redes. Así, dos Em-ATB tienen la HPBB: cetarolina 600 mg (dos veces al día) y piperacilina 2000 mg (dos veces al día). Para la mortalidad, se construyeron tres redes. Así, tres Em-ATB tienen la HPBB: ceftriaxona 2000 mg (una vez al día) más levofloxacino 500 (dos veces al día), ertapenem 1000 mg (dos veces al día) y amikacina 250 mg (dos veces al día) más claritromicina 500 mg (dos veces al día). La certeza de la evidencia para cada resultado es moderada. Conclusiones: Para la tasa de curación, ceftarolina y piperacilina son las opciones con la HPBB. Sin embargo, para la tasa de mortalidad, las opciones son ceftriaxona más levofloxacino, ertapenem y amikacina más claritromicina. Parece necesario realizar un ECA que compare los tratamientos con el HPBB para cada evento (curación o mortalidad) (CRD42017060692).Objective: The main aim of this network meta-analysis is to identify the empiric antibiotic (Em-ATB) with the highest probability of being the best (HPBB) in terms of (1) cure rate and (2) mortality rate in hospitalised patients with community acquired pneumonia (CAP) . Method: Inclusion criteria: (1) adult patients (>16 years old) diagnosed with CAP that required hospitalisation; (2) randomised to at least two different Em-ATBs, (3) that report cure rate and (4) are written in English or Spanish. Exclusion criteria: (1) ambiguous antibiotics protocol and (2) published exclusively in abstract or letter format. Data sources: Medline, Embase, Cochrane and citation reviews from 1 January 2000 to 31 December 2018. Risk of bias: Cochrane's tool. Quality of the systematic review (SR): A MeaSurement Tool to Assess systematic Reviews-2. Certainity of the evidence: Grading of Recommendations Assessment, Development and Evaluation. Statistical analyses: frequentist method performed with the 'netmeta' library, R package. Results: 27 randomised controlled trials (RCTs) from the initial 41 307 screened citations were included. Regarding the risk of bias, more than one quarter of the studies presented low risk and no study presented high risk in all domains. The SR quality is moderate. For cure, two networks were constructed. Thus, two Em-ATBs have the HPBB: cetaroline 600 mg (two times a day) and piperacillin 2000 mg (two times a day). For mortality, three networks were constructed. Thus, three Em-ATBs have the HPBB: ceftriaxone 2000 mg (once a day) plus levofloxacin 500 (two times a day), ertapenem 1000 mg (two times a day) and amikacin 250 mg (two times a day) plus clarithromycin 500 mg (two times a day). The certainity of evidence for each results is moderate. Conclusion: For cure rate, ceftaroline and piperaciline are the options with the HPBB. However, for mortality rate, the options are ceftriaxone plus levofloxacin, ertapenem and amikacin plus clarithromycin. It seems necessary to conduct an RCT that compares treatments with the HPBB for each event (cure or mortality) (CRD42017060692)

    Sterilization Procedure for Temperature-Sensitive Hydrogels Loaded with Silver Nanoparticles for Clinical Applications

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    Anti-bacterial agents; Post-operative infections; Silver nanoparticlesAgents antibacterians; Infeccions postoperatòries; Nanopartícules de plataAgentes antibacterianos; Infecciones postoperatorias; Nanopartículas de plataHydrogels (HG) have recognized benefits as drug delivery platforms for biomedical applications. Their high sensitivity to sterilization processes is however one of the greatest challenges regarding their clinical translation. Concerning infection diseases, prevention of post-operatory related infections is crucial to ensure appropriate patient recovery and good clinical outcomes. Silver nanoparticles (AgNPs) have shown good antimicrobial properties but sustained release at the right place is required. Thus, we produced and characterized thermo-sensitive HG based on Pluronic® F127 loaded with AgNPs (HG-AgNPs) and their integrity and functionality after sterilization by dry-heat and autoclave methods were carefully assessed. The quality attributes of HG-AgNPs were seriously affected by dry-heat methods but not by autoclaving methods, which allowed to ensure the required sterility. Also, direct sterilization of the final HG-AgNPs product proved more effective than of the raw material, allowing simpler production procedures in non-sterile conditions. The mechanical properties were assessed in post mortem rat models and the HG-AgNPs were tested for its antimicrobial properties in vitro using extremely drug-resistant (XDR) clinical strains. The produced HG-AgNPs prove to be versatile, easy produced and cost-effective products, with activity against XDR strains and an adequate gelation time and spreadability features and optimal for in situ biomedical applications

    Risk Factors of Mortality from All Asbestos-Related Diseases: A Competing Risk Analysis

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    Background. The mortality from all malignant and nonmalignant asbestos-related diseases remains unknown. The authors assessed the incidence and risk factors for all asbestos-related deaths. Methods. The sample included 544 patients from an asbestos-exposed community in the area of Barcelona (Spain), between Jan 1, 1970, and Dec 31, 2006. Competing risk regression through a subdistribution hazard analysis was used to estimate risk factors for the outcomes. Results. Asbestos-related deaths were observed in 167 (30.7%) patients and 57.5% of these deaths were caused by some type of mesothelioma. The incidence rate after diagnosis was 3,600 per 100,000 person-years. In 7.5% of patients death was non-asbestos-related, while pleural and peritoneal mesothelioma were identified in 87 (16.0%) and 18 (3.3%) patients, respectively. Conclusions. Age, sex, household exposure, cumulative nonmalignant asbestos-related disease, and single malignant pathology were identified as risk factors for asbestos-related death. These findings suggest the need to develop a preventive approach to the community and to improve the clinical follow-up process of these patients

    Risk Factors of Mortality from All Asbestos-Related Diseases: A Competing Risk Analysis

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    Amiant; Mortalitat; Factors de riscAsbestos; Mortality; Risk factorsAmianto; Mortalidad; Factores de riesgoBackground. Themortality fromallmalignant and nonmalignant asbestos-related diseases remains unknown. The authors assessed the incidence and risk factors for all asbestos-related deaths. Methods.Thesampleincluded544patientsfrom anasbestos- exposed community in the area of Barcelona (Spain), between Jan 1, 1970, and Dec 31, 2006. Competing risk regression through a subdistribution hazard analysis was used to estimate risk factors for the outcomes. Results. Asbestos-related deaths were observed in 167 (30.7%) patients and 57.5% of these deathswere caused by some type ofmesothelioma. The incidence rate aſter diagnosis was 3,600 per 100,000 person-years. In 7.5%of patients deathwas non-asbestos-related,while pleural and peritonealmesotheliomawere identified in 87 (16.0%) and 18 (3.3%) patients, respectively. Conclusions. Age, sex, household exposure, cumulative nonmalignant asbestos-related disease, and single malignant pathology were identified as risk factors for asbestos-related death. These findings suggest the need to develop a preventive approach to the community and to improve the clinical follow-up process of these patients. 1

    La enseñanza del metabolismo: retos y oportunidades

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    En el marco del Proyecto de Innovación Educativa de la Universidad de Málaga PIE15-163, cuya descripción y resultados incluimos, decidimos que esta era una excelente oportunidad para reflexionar acerca de la enseñanza del metabolismo y de poner por escrito dichas reflexiones en un libro. Quisimos y pudimos contar con la colaboración de buena parte de los compañeros del Departamento de Biología Molecular y Bioquímica que apoyaron con su firma el proyecto PIE15-163 y extendimos nuestra invitaciones a otros compañeros de dentro y fuera de la Universidad de Málaga. Del Departamento de Biología Molecular y Bioquímica de la Universidad de Málaga hemos recibido aportaciones de los catedráticos Victoriano Valpuesta Fernández, Ana Rodríguez Quesada y Antonio Heredia Bayona, los profesores titulares María Josefa Pérez Rodríguez, José Luis Urdiales Ruiz e Ignacio Fajardo Paredes y la investigadora postdoctoral y profesora sustituta interina Beatriz Martínez Poveda. De otros departamentos de la Universidad de Málaga hemos contado con las aportaciones de la catedrática del Departamento de Especialidades Quirúrgicas, Bioquímica e Inmunología Pilar Morata Losa, del catedrático del Departamento de Lenguajes y Ciencias de la Computación José Francisco Aldana Montes y los componentes de su grupo de investigación Khaos Ismael Navas Delgado, María Jesús García Godoy, Esteban López Camacho y Maciej Rybinski, del catedrático Ángel Blanco López, del Área de Conocimiento de Didáctica de las Ciencias Experimentales y del Doctor en Ciencias Químicas y actual doctorando del Programa de Doctorado "Educación y Comunicación Social" Ángel Luis García Ponce. De fuera de la Universidad de Málaga, hemos contado con las aportaciones del catedrático de la Universidad de La Laguna Néstor V. Torres Darias, de la catedrática de la Universitat de les Illes Balears Pilar Roca Salom y de sus compañeros los profesores Jorge Sastre Serra y Jordi Oliver, de los catedráticos de la Universidad de Granada Rafael Salto González y María Dolores Girón González y su colaborador el Dr. José Dámaso Vílchez Rienda, del profesor titular de la Universidad de Alcalá Ángel Herráez, del investigador postdoctoral de la Universidad de Erlangen (Alemania) Guido Santos y del investigador postdoctoral de la empresa Brain Dynamics Carlos Rodríguez Caso.Hemos estructurado los contenidos del libro en diversas secciones. La primera presenta el Proyecto en cuyo marco se ha gestado la iniciativa que ha conducido a la edición del presente libro. La segunda sección la hemos titulado "¿Qué metabolismo?" e incluye diversas aportaciones personales que reflexionan acerca de qué metabolismo debe conocer un graduado en Bioquímica, en Biología, en Química, en Farmacia o en Medicina, así como una aportación acerca de qué bioquímica estructural y enzimología son útiles y necesarias para un estudiante que vaya a afrontar el estudio del metabolismo. La tercera sección, "Bases conceptuales", analiza las aportaciones del aprendizaje colaborativo, el contrato de aprendizaje y el aprendizaje basado en la resolución de casos prácticos a la mejora del proceso enseñanza-aprendizaje dentro del campo de la Bioquímica y Biología Molecular, más concretamente en el estudio del metabolismo. La cuarta sección se titula "Herramientas", es la más extensa e incluye las diversas aportaciones centradas en propuestas concretas de aplicación relevantes y útiles para la mejora de la docencia-aprendizaje del metabolismo. Sigue una sección dedicada a presentar de forma resumida los "Resultados" del proyecto PIE15-163. El libro concluye con una "coda final" en la que se reflexiona acerca del aprendizaje de la Química a la luz de la investigación didáctica.Patrocinado por el Proyecto de Innovación Educativa de la Universidad de Málaga PIE15-16

    Determination of essential biomarkers in lung cancer: a real-world data study in Spain.

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    Background: The survival of patients with lung cancer has substantially increased in the last decade by about 15%. This increase is, basically, due to targeted therapies available for advanced stages and the emergence of immunotherapy itself. This work aims to study the situation of biomarker testing in Spain. Patients and Methods: The Thoracic Tumours Registry (TTR) is an observational, prospective, registry-based study that included patients diagnosed with lung cancer and other thoracic tumours, from September 2016 to 2020. This TTR study was sponsored by the Spanish Lung Cancer Group (GECP) Foundation, an independent, scientific, multidisciplinary oncology society that coordinates more than 550 experts and 182 hospitals across the Spanish territory. Results: 9,239 patients diagnosed with stage IV non-small cell lung cancer (NSCLC) between 2106 and 2020 were analysed. 7,467 (80.8%) were non-squamous and 1,772 (19.2%) were squamous. Tumour marker testing was performed in 85.0% of patients with non-squamous tumours vs 56.3% in those with squamous tumours (p-value <0.001). The global testing of EGFR, ALK, and ROS1 was 78.9%, 64.7%, 35.6% respectively, in non-squamous histology. PDL1 was determined globally in the same period (46.9%), although if we focus on the last 3 years it exceeds 85%. There has been a significant increase in the last few years of all determinations and there are even close to 10% of molecular determinations that do not yet have targeted drug approval but will have it in the near future. 4,115 cases had a positive result (44.5%) for either EGFR, ALK, KRAS, BRAF, ROS1, or high PDL1. Conclusions: Despite the lack of a national project and standard protocol in Spain that regulates the determination of biomarkers, the situation is similar to other European countries. Given the growing number of different determinations and their high positivity, national strategies are urgently needed to implement next-generation sequencing (NGS) in an integrated and cost-effective way in lung cancer
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