57 research outputs found

    Algoritmo de cálculo de los coeficientes de difusión de agua en zeolitas naturales cubanas

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    En el presente trabajo se describe el estudio de la cinética de adsorción de agua realizado a tres de las zeolitas naturales cubanas más estudiadas. La necesidad e importancia, así como la novedad y actualidad de este tipo de estudio son argumentadas en la parte introductoria. Empleando los elementos de la teoría de la transferencia de sustancia desarrollada por Ruthven para el caso de los materiales porosos y la teoría del llenado volumétrico de microporos de Dubinin se diseñó un procedimiento de cálculo para los coeficientes de transferencia y de difusión de vapor de agua en tales materiales. El algoritmo gráfico-numérico se desarrolló para la zona de predominio de las interacciones no específicas del modelo de Dubinin. Este método de cálculo se aplicó al estudio de la cinética de adsorción de vapor de agua por las zeolitas de los yacimientos de Tasajera, Castilla y Palmarito en sus diferentes formas catiónicas. Los cálculos se efectuaron a partir de datos de la cinética y la termodinámica de la adsorción de agua obtenidos mediante un equipo estático volumétrico clásico. Los coeficientes de trasferencia de vapor de agua y de difusión de este en las muestras estudiadas están en el orden de lo reportado para materiales de esta naturaleza. En los cálculos se empleó el radio granulométrico en vez del radio del cristal zeolítico, argumentándose el porqué de tal elección de acuerdo con los diferentes criterios que han sido reportados. Se obtuvo además que la etapa limitante del proceso cinético es la difusión intercristalina

    Niveles del factor de crecimiento derivado de plaquetas en el plasma rico en plaquetas antes y despues de antiagregantes plaquetarios

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    El PDGF es uno de los mitógenos más potentes para el tejido conectivo, su secreción parece ser particularmente importante cuando la fuente es el Plasma Rico en Plaquetas (PRP), de allí el rol protagónico de este último en la regeneración tisular. Se determinó mediante ELISA los niveles de PDGFBB en el PRP, Plasma Pobre en Plaquetas (PPP) y Exudado de 32 sujetos sanos antes y 24 horas después de ingerir AAS (Aspirina) y Clopidogrel. Los niveles basales de PDGFBB ueron de 10, 6 ± 1, 9 ng/ml (PPP), 12, 12 ± 2, 5 ng/ml (PRP) y 10, 84 ± 1, 68 ng/ml (Exudado). Mientras que después del tratamiento con AAS las concentraciones de PDGFBB estuvieron en 8, 96 ± 1, 4 ng/ml (PPP), 11, 36 ± 1, 48ng/ml (PRP), 11, 11 ± 1, 14ng/ml (Exudado) y para el Clopidogrel fueron de 8, 53 ± 0, 59 ng/ml (PPP), 9, 65 ± 1, 17 ng/ml (PRP) y 8, 51 ± 0, 75 ng/ml (Exudado). Se notó que luego de la administración de AAS y Clopidogrel los valores de PDGFBB disminuyeron de manera estadísticamente significativa, en especial para el grupo del Clopidogrel. El AAS pareció afectar en menor grado las concentraciones de PDGFBB, lo cual puede ser atribuible al mecanismo de acción farmacológica diferencial existente entre la AAS y Clopidogrel. No se encontró correlación entre el recuento plaquetario y los niveles basales de PDGFBB del PRP. PDGF levels in platelet-rich plasma before and after anti platelets drugs Abstract PDGF is one of the most potent mitogen for connective tissue, its secretion appears to be particularly important when the source is Platelet Rich Plasma (PRP), hence the latter leading role in tissue regeneration. ELISA PDGFBB levels in PRP, Platelet Poor Plasma (PPP) and exudates, were determined in 32 healthy subjects before and 24 hours after ingestion of Aspirin (ASA) and Clopidogrel (CLO). PDGFBB baseline levels were 10.6 ± 1.9 ng / ml (PPP), 12.12 ± 2.5 ng / ml (PRP) and 10.84 ± 1.68 ng / ml (exudate). After treatment with ASA concentrations were PDGFBB in 8.96 ± 1.4 ng / ml (PPP), 11.36 ± 1.48 ng / ml (PRP), 11.11 ± 1.14 ng / ml (exudate) and the Clopidogrel were 8.53 ± 0.59 ng / ml (PPP), 9.65 ± 1.17 ng / ml (PRP) and 8.51 ± 0.75 ng / ml (exudate). It was noted that after the administration of ASA and CLO, PDGFBB values statistically significantly decreased, especially for the group of CLO. ASA lesser extent appears to affect th concentrations of PDGFBB, which may be attributable to the pharmacological mechanism of action between the ASA and Clopidogrel. No correlation was found between platelet count and baseline levels of PRP PDGFBB

    Looking for Crumbs in the Obesity Forest: Anti-obesity Interventions and Obesity-Associated Cardiometabolic Traits in the Mexican Population. History and Systematic Review With Meta-Analyses

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    Mexicans and Mexican Americans share culture, genetic background, and predisposition for chronic complications associated with obesity and diabetes making imperative efficacious treatments and prevention. Obesity has been treated for centuries focused-on weight loss while other treatments on associated conditions like gout, diabetes (T2D), and hypertriglyceridemia. To date, there is no systematic review that synthesizes the origin of obesity clinics in Mexico and the efforts to investigate treatments for obesity tested by randomized clinical trials (RCT). We conducted systematic searches in Pubmed, Scopus, and Web of Science to retrieve anti-obesity RCT through 2019 and without an inferior temporal limit. The systematic review included RCT of anti-obesity treatments in the Mexican adult population, covering alternative medicine, pharmacological, nutritional, behavioral, and surgical interventions reporting metabolism-associated traits such as BMI, weight, waist circumference, triglycerides, glucose, among others. Only the studies with at least 3 months of treatment were included in the meta-analyses in order to reduce placebo effects. We found 634 entries, after removal of duplicates and screening the studies based on eligibility criteria, we analyzed 43 national, and 2 multinational-collaborative studies. Most of the national studies had small sample sizes, and the implemented strategies do not have replications in the population. The nutrition/behavioral interventions were difficult to blind, and most studies have medium-to-high risk of bias. Nutritional/behavioral interventions and medications showed effects on BMI, waist circumference, and blood pressure. Simple measures like pure water instead of sweet beverages decrease triglycerides and systolic blood pressure. Dark chocolate showed the highest effect for BMI and high blood pressure, and treatment with insulin increased weight in those with T2D. The study of obesity in Mexico has been on-going for more than four decades, the interest on RCT just increased until this millennium, but with small sample sizes and lack of replication. The interventions affect different cardiometabolic associated traits, which should be analyzed in detail in the population living near the Mexico-U.S. border; therefore, bi-national collaboration is desirable to disentangle the cultural effects on this population\u27s treatment response

    Randomized Clinical Trials of obesity treatments in Mexican population. Systematic Review and Meta-Analysis

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    Background: Mexicans and Mexican Americans share similar culture, genetic background, and predisposition for obesity and diabetes. Randomized clinical trials (RCT) assessing obesity treatments (ObT) are reliable to assess efficacy. To date, there is no systematic review to investigate ObT tested by RCT in Mexican adults. Methods: We conducted systematic searches in Pubmed, Scopus, and Web of Science to retrieve ObT RCT from 1990 to 2019. The ObT included alternative medicine, pharmacological, nutritional, behavioral, and surgical interventions. The analyzed RCT were at least three months of duration, and reported: BMI, weight, waist circumference, triglycerides, glucose and blood pressure. Results: We found 634 entries; after removal of duplicates and exclusions based on eligibility criteria, we analyzed 43 and 2 multinational-collaborative studies. Most of the national studies had small sample sizes, and did not have replications from other studies. The nutrition/behavioral interventions were difficult to blind, and most studies had medium to high risk of bias. Random effects meta-analysis of nutritional/behavioral interventions and medications showed effects on BMI, waist circumference, and blood pressure. Simple measures like plain water instead of sweet beverages decreased triglycerides and systolic blood pressure. Participants with obesity and hypertension had beneficial effects with antioxidants, and the treatment with insulin increased weight in those with T2D. Conclusions: The RCT’s in Mexico reported effects on metabolic components despite small sample sizes and lack of replication. In the future we should analyze ObT in population living on the U.S.-Mexico border; therefore, bi-national collaboration is desirable to disentangle cultural effects on ObT response

    PERSPECTIVA PSICOSOCIAL DE LOS DERECHOS HUMANOS

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    Hoy en día es imprescindible abordar el problema de los derechos desde una perspectiva holística que integre la posición que el individuo ocupa en la sociedad y el impacto de los hechos sociales sobre su persona. Esta perspectiva va por lo tanto más allá del enfoque clásico de las violaciones a los derechos civiles y políticos de los ciudadanos sino, también incluye sus derechos económicos, sociales y culturales. Cualquier enfoque de tipo holístico debe entender al ser humano en su ambiente, social, cultural, natural y en función a todas las estructuras existentes, por más sutiles que sean o invisibles que parezcan. Precisamente este libro permite apreciar la dimensión amplia y compleja del ser en sociedad y las interacciones que de ambas partes se generan y las ramificaciones que producen. No es un ejercicio fácil y los editores de este volumen han logrado un salto cuántico al poder congregar en un solo espacio miradas que en otras circunstancias podrían haber sido opuestas y hasta contrarias a nuestra comprensión de problemas que, en efecto, tienen raíces comunes. El libro está dividido en 5 secciones, El espíritu de los tiempos actuales y los Derechos Humanos, Construcción ciudadana y ejercicio de los Derechos Humanos, Violaciones a Derechos Humanos, victimizaciones y su atención, Ejercicio de los Derechos Humanos y situaciones disruptivas y Defensa y defensores de Derechos Humanos.Manuel Gutiérrez Romero Jessica Ruiz Magañ

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Recomendaciones para la inclusión del género en los contenidos de investigación

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    Siguiendo las recomendaciones de las instituciones europeas de investigación, se debe plantear la investigación como un ciclo completo en el que se incluya el impacto de los resultados sobre la sociedad, la economía, las oportunidades de negocio, la creatividad, la innovación, el uso de recursos, los usuarios finales, el desarrollo local o global, el medioambiente, etc., y es en estos aspectos donde la inclusión de consideraciones de género aporta calidad a la investigación. El análisis sobre las distintas necesidades, actitudes y preferencias de ambos sexos incrementa la relevancia social y la calidad del avance científico alcanzado. La Comisión de Mujer y Ciencia ya señaló en 2015 y en 2018 la necesidad de recibir formación para la adecuada inclusión de las cuestiones de género en los contenidos de investigación. En este sentido, revisó el material disponible como herramientas para tal fin y promovió la impartición de un curso de formación interna del CSIC específico en la materia. En general, se encuentra gran dificultad (y también alguna resistencia) en la aplicación de la dimensión de género en los contenidos de investigación. La CMyC presenta esta guía informal como ayuda para completar las cuestiones de integración del género en los contenidos, de modo que sirvan de apoyo en la preparación de solicitudes tanto en las convocatorias nacionales como europeas, contribuyendo así a los objetivos del III Plan de Igualdad (Eje 7) y a la estrategia HRS4S (Acción 17) del CSIC.Peer reviewe

    Immunotherapeutic effects of intratumoral nanoplexed poly I:C

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    Poly I:C is a powerful immune adjuvant as a result of its agonist activities on TLR-3, MDA5 and RIG-I. BO-112 is a nanoplexed formulation of Poly I:C complexed with polyethylenimine that causes tumor cell apoptosis showing immunogenic cell death features and which upon intratumoral release results in more prominent tumor infiltration by T lymphocytes. Intratumoral treatment with BO-112 of subcutaneous tumors derived from MC38, 4 T1 and B16- F10 leads to remarkable local disease control dependent on type-1 interferon and gamma-interferon. Some degree of control of non-injected tumor lesions following BO-112 intratumoral treatment was found in mice bearing bilateral B16-OVA melanomas, an activity which was enhanced with co-treatment with systemic anti-CD137 and anti-PD-L1 mAbs. More abundant CD8+ T lymphocytes were found in B16-OVA tumor-draining lymph nodes and in the tumor microenvironment following intratumoral BO-112 treatment, with enhanced numbers of tumor antigen-specific cytotoxic T lymphocytes. Genome-wide transcriptome analyses of injected tumor lesions were consistent with a marked upregulation of the type-I interferon pathway. Inspired by these data, intratumorally delivered BO-112 is being tested in cancer patients (NCT02828098)

    Ischaemic conditioning and targeting reperfusion injury: a 30 year voyage of discovery

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    To commemorate the auspicious occasion of the 30th anniversary of IPC, leading pioneers in the field of cardioprotection gathered in Barcelona in May 2016 to review and discuss the history of IPC, its evolution to IPost and RIC, myocardial reperfusion injury as a therapeutic target, and future targets and strategies for cardioprotection. This article provides an overview of the major topics discussed at this special meeting and underscores the huge importance and impact, the discovery of IPC has made in the field of cardiovascular research
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