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Search Results: 1 - 10 of 191866 matches for " Gómez-Estrada "
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In vitro antimalarial activity of fractions and constituents isolated from Tabebuia billbergii Actividad antimalárica in vitro de fracciones y constituyentes aislados de Tabebuia billbergii
Harold Gómez-Estrada,Ricardo Gaitán-Ibarra,Fredyc Díaz-Castillo,Hilda A Pérez
Revista Cubana de Plantas Medicinales , 2012,
Abstract: Introduction: in vitro antimalarial activity of naphthoquinones (1-5), isolated from Tabebuia billbergii (Bureau & K. Schum.) Standl., was investigated. Tabebuia billbergii, commonly known as guayacán, is a plant traditionally used in the Amazon in numerous conditions like bacterial and fungal infections, fever, syphilis, malaria, trypanosomiasis, as well as stomach and bladder disorders, and tumours. Objective: to study the dichloromethane extracts of both the trunk and the inner bark of Tabebuia billbergii and to demonstrate the antimalarial activity of some of its bioactive components. Methods: some bioactive components were evaluated for the antimalarial activity against Plasmodium berghei, by using the inhibition of the differentiation cycle of the parasite measure by the 3H-hypoxanthine incorporation and compared to that obtained for chloroquine. Results: conventional chromatographic techniques and bioassay-guided fractionation (Artemia salina) allowed isolating from the active fractions one naphthoquinone (lapachol) and four naphtho-furan-4,9-diones. These compounds proved to have an important antiplasmodial effect, with very encouraging IC50's, especially when compared to the results shown by Chloroquine in the same experiment. In addition, two triterpenes, β-sitosterol and stigmasterol, were obtained from the bark. Conclusions: the activity-guided fractionation (A. salina) of dichloromethane extracts of the trunk and the inner bark of Tabebuia billbergii led to the isolation and the identification of five quinonoid compounds with antiplasmodial effect. The significant inhibitory activity in vitro against Plasmodium berghei observed for compound 2-acetyl-naphtho-[2,3b]-furan-4,9-dione allow us to present them as a potential antimalarial compound. Introducción: se evaluó la actividad antimalárica in vitro de una serie de naftoquinonas (1-5), aisladas de Tabebuia billbergii (Bureau & K. Schum.) Standl., que es conocida comúnmente como guayacán, una planta utilizada tradicionalmente en la Amazonía en numerosos problemas de salud como infecciones bacterianas y fúngicas, fiebre, sífilis, paludismo, tripanosomiasis, así como en problemas estomacales, tumores y trastornos de la vejiga. Objetivo: estudiar los extractos en diclorometano tanto del tronco como la corteza interna de Tabebuia billbergii y evaluar la actividad antimalárica de algunos de sus componentes bioactivos. Métodos: la actividad antimalárica contra Plasmodium berghei se evaluó en algunos componentes bioactivos, por la inhibición del ciclo de la diferenciación de la medida de los parásit
Química y biología del extracto etanólico del epicarpio de Crescentia cujete L. (totumo)
Espitia-Baena,Jorge Eliecer; Duran-Sandoval,Harriette del Rosario; Fandi?o-Franky,Jaime; Díaz-Castillo,Fredyc; Gómez-Estrada,Harold Alberto;
Revista Cubana de Plantas Medicinales , 2011,
Abstract: introduction: crescentia cujete l. (bignonaceae) tree known in colombia as totumo, is a characteristic species of tropical climates. its most distinctive feature is the fruit, which is a spherical pumpkin with hard and woody peel, and a gelatinous pulp having a lot of seeds. objective: to conduct the chemical and biological ethanol extract of crescentia cujete l. epicarp. methods: vegetal material was harvested and the total ethanol extract was obtained. then, preliminary phytochemical screening, direct physical and chemical tests on vegetal material, the quantification of heavy metals and finally the biological study against aedes aegypti l. (culicidae) larvae in stages iii and iv, artemia salina leach. (artemiidae) larvae and apical cells of allium cepa l. (amaryllidaceae) roots. results: the presence of three groups of secondary metabolites, that is, flavonoids, steroids and triterpenes were identified. likewise, the water and ash content on dry basis was quantified as well as the levels of concentration of some heavy metals such as cadmium, chromium, mercury and lead were estimated. the biological study revealed that the extract did not show acute toxicity either in any of the tested biological systems or at the concentrations and the time of experimentation. conclusions: the information obtained in this research is an important resource for the scientific community and provides elements associated to the chemical nature and the biological behavior of the totumo ′s epicarp not contained in previous reports.
In vitro antimalarial activity of fractions and constituents isolated from Tabebuia billbergii
Gómez-Estrada,Harold; Gaitán-Ibarra,Ricardo; Díaz-Castillo,Fredyc; Pérez,Hilda A; Medina,José D;
Revista Cubana de Plantas Medicinales , 2012,
Abstract: introduction: in vitro antimalarial activity of naphthoquinones (1-5), isolated from tabebuia billbergii (bureau & k. schum.) standl., was investigated. tabebuia billbergii, commonly known as guayacán, is a plant traditionally used in the amazon in numerous conditions like bacterial and fungal infections, fever, syphilis, malaria, trypanosomiasis, as well as stomach and bladder disorders, and tumours. objective: to study the dichloromethane extracts of both the trunk and the inner bark of tabebuia billbergii and to demonstrate the antimalarial activity of some of its bioactive components. methods: some bioactive components were evaluated for the antimalarial activity against plasmodium berghei, by using the inhibition of the differentiation cycle of the parasite measure by the 3h-hypoxanthine incorporation and compared to that obtained for chloroquine. results: conventional chromatographic techniques and bioassay-guided fractionation (artemia salina) allowed isolating from the active fractions one naphthoquinone (lapachol) and four naphtho-furan-4,9-diones. these compounds proved to have an important antiplasmodial effect, with very encouraging ic50's, especially when compared to the results shown by chloroquine in the same experiment. in addition, two triterpenes, β-sitosterol and stigmasterol, were obtained from the bark. conclusions: the activity-guided fractionation (a. salina) of dichloromethane extracts of the trunk and the inner bark of tabebuia billbergii led to the isolation and the identification of five quinonoid compounds with antiplasmodial effect. the significant inhibitory activity in vitro against plasmodium berghei observed for compound 2-acetyl-naphtho-[2,3b]-furan-4,9-dione allow us to present them as a potential antimalarial compound.
Folk medicine in the northern coast of Colombia: an overview
Harold Gómez-Estrada, Fredyc Díaz-Castillo, Luís Franco-Ospina, Jairo Mercado-Camargo, Jaime Guzmán-Ledezma, José Medina, Ricardo Gaitán-Ibarra
Journal of Ethnobiology and Ethnomedicine , 2011, DOI: 10.1186/1746-4269-7-27
Abstract: Data on the use of medicinal plants were collected using structured interviews and through observations and conversations with local communities. A total of 1225 participants were interviewed.Approximately 30 uses were reported for plants in traditional medicine. The plant species with the highest fidelity level (Fl) were Crescentia cujete L. (flu), Eucalyptus globulus Labill. (flu and cough), Euphorbia tithymaloides L. (inflammation), Gliricidia_sepium_(Jacq.) Kunth (pruritic ailments), Heliotropium indicum L. (intestinal parasites) Malachra alceifolia Jacq. (inflammation), Matricaria chamomilla L. (colic) Mentha sativa L. (nervousness), Momordica charantia L. (intestinal parasites), Origanum vulgare L. (earache), Plantago major L. (inflammation) and Terminalia catappa L. (inflammation). The most frequent ailments reported were skin affections, inflammation of the respiratory tract, and gastro-intestinal disorders. The majority of the remedies were prepared from freshly collected plant material from the wild and from a single species only. The preparation of remedies included boiling infusions, extraction of fresh or dry whole plants, leaves, flowers, roots, fruits, and seeds. The parts of the plants most frequently used were the leaves. In this study were identified 39 plant species, which belong to 26 families. There was a high degree of consensus from informants on the medical indications of the different species.This study presents new research efforts and perspectives on the search for new drugs based on local uses of medicinal plants. It also sheds light on the dependence of rural communities in Colombia on medicinal plants.About 80% of the populations of developing countries continue using traditional resources in health care [1-6]. The main goal of ethnopharmacology is to identify novel compounds derived from plants and animals for use in indigenous medical systems. This knowledge can be used in the development of new pharmaceuticals. Most of the literature
Aproximación al estudio de las tendencias e impacto de la producción científica en salud ocupacional: Estudio de una publicación periódica
Estrada,María; Sánchez Tovar,Ligia; Gómez,Wuilman;
Salud de los Trabajadores , 2006,
Abstract: an exploratory research was undertaken. the study seeks to identify some characteristics of the scientific production in occupational health, the lines of investigation with more coverage in the "salud de los trabajadores" journal and its impact on post-graduate dissertations of occupational health and hygiene of workplace, universidad de carabobo (uc) and servicio autónomo instituto de altos estudios "dr. arnoldo gabaldon" (iaes). it was taken as reference the 79 scientific articles published in the "salud de los trabajadores" journal from 1993 to 2005; as well as 72 post-graduate publications of the 118 presented during that period in occupational health and hygiene of workplace post graduate studies of the uc/iaes. it observed a constant production of 6 articles per volume. the 20,25 % of articles published belonged to work sociology and workers′ health, and only 1,26% of articles were concerned with environmental health education and social security. with regards to author?s habits of citations there were higher self-references registered during the years 2000, 2002 and 2003. with regards to the impact of the journal in post-graduate dissertations of occupational health and hygiene of workplace, it was detected that the years of higher citation of the journal were 1995, 1998 and 2005. the study reveals that there is not a constant in the citation habit of the articles of the "salud de los trabajadores" journal in the studied period. it is recommended making deeper research with more scientometric indicators.
Aproximación al estudio de las tendencias e impacto de la producción científica en salud ocupacional: Estudio de una publicación periódica Approach to the study the tendencies and impact of the scientific production in occupational health: A journal study
María Estrada,Ligia Sánchez Tovar,Wuilman Gómez
Salud de los Trabajadores , 2006,
Abstract: Estudio exploratorio que pretende identificar algunas características de la producción cientí.ca en salud ocupacional, las líneas de investigaciones con mayor cobertura en la revista Salud de los Trabajadores (ST), así como su impacto en los trabajos de grado presentados en el Postgrado de Salud Ocupacional e Higiene del Ambiente Laboral, de la Universidad de Carabobo (UC) y el Servicio Autónomo Instituto de Altos Estudios "Dr. Arnoldo Gabaldon" (IAES). Se analizan los 79 artículos originales publicados en la Revista Salud de los Trabajadores, desde el a o 1993 hasta el 2005, y 72 trabajos de grado, de los 118 presentados durante ese período en el Postgrado en Salud Ocupacional e Higiene del Ambiente Laboral de la UC/IAES. Los resultados revelan una periodicidad permanente, con un promedio de 6 artículos por volumen; el mayor número de artículos, publicados durante el lapso estudiado, estuvo concentrado en las áreas de Sociología del Trabajo e Higiene Ocupacional, ambas con un 20,25%; mientras que las líneas de investigación menos abordadas en los artículos fueron Educación Ambiental y Seguridad Social, con tan solo un 1,26% para cada una. Respecto al hábito de citación de los autores, el mayor porcentaje de autoreferencias de la revista ST se registró en los volúmenes publicados durante los a os 2000, 2002 y 2003. En relación al impacto de la revista en la literatura gris del Postgrado en Salud Ocupacional e Higiene del Ambiente laboral, se detectó que los a os de mayor citación de la revista fueron 1995, 1998 y 2005. Lo antes expuesto revela que no se mantiene constante el hábito de citación de los artículos de la revista ST en el período estudiado. El nivel exploratorio del estudio y el carácter preliminar de los resultados sugieren profundizar la investigación incorporando más indicadores de interés cienciométrico. An exploratory research was undertaken. The study seeks to identify some characteristics of the scientific production in occupational health, the lines of investigation with more coverage in the "Salud de los Trabajadores" Journal and its impact on post-graduate dissertations of Occupational Health and Hygiene of Workplace, Universidad de Carabobo (UC) and Servicio Autónomo Instituto de Altos Estudios "Dr. Arnoldo Gabaldon" (IAES). It was taken as reference the 79 scientific articles published in the "Salud de los Trabajadores" journal from 1993 to 2005; as well as 72 Post-graduate publications of the 118 presented during that period in Occupational Health and Hygiene of Workplace post graduate studies of the UC/IAES. It observed a consta
ANáLISIS DE INCONFIABILIDAD A UN PROCESO DE CONSTRUCCION DE ROLLOS DE PAPEL UTILIZANDO ARBOL DE FALLOS
SANTIAGO GóMEZ ESTRADA,HUGO BALDOMIRO CANO,FABIO ANTONIO OCAMPO
Scientia Et Technica , 2009,
Abstract: Este documento es un complemento del anterior artículo titulado "análisis de confiabilidad aplicado a una conformadora de rollos empleando la técnica de modos de fallo", en el cual se presentó un análisis de confiabilidad al proceso de construcción de rollos de papel. Ahora se muestra la ejecución de un análisis de inconfiabilidad utilizando la técnica de árbol de fallo, obteniendo resultados comparativos y similares con los de la técnica de modos de fallo.
La higiene del ganado y la fasciolosis bovina, Medellín y Rionegro, 1914-1970
ESTRADA ORREGO,VICTORIA EUGENIA; GóMEZ GóMEZ,MAURICIO; VELáSQUEZ TRUJILLO,LUZ ELENA;
Iatreia , 2006,
Abstract: in the approach of bovine fasciolosis biomedical studies, historical research has become necessary. here we deal with the historical aspects in medellín and rionegro during most of xx century. the importance and dynamism of cattle activity in antioquia during xx century partially explains private and official interests in improving this sector of economy through disease prevention. since 1914, a local sanitary policy emerges, concerning control for food coming from animal brood. while milk production increases, the requirement of veterinary control and teaching appears in colombia. although bovine fasciolosis reports can be followed since the first decades of xx century, it does not appear as a main concern in biomedical and sanitary reports from medellín and rionegro. studies regarding this disease, published in several national newspapers and journals from the first middle of xx century, circulated among specialists and did not have an influence in cattle in colombia. moreover, an evaluation of documents belonging to the last decades of xx century suggests that, despite the high disease incidence, fasciolosis research has not had an impact in the development of prevention and control programs.
La higiene del ganado y la fasciolosis bovina, Medellín y Rionegro, 1914-1970 Cattle hygiene and bovine fasciolosis. Medellín and Rionegro 1914-1970
Victoria Eugenia Estrada Orrego,Mauricio Gómez Gómez,Luz Elena Velásquez Trujillo
Iatreia , 2006,
Abstract: Al estudiar la fasciolosis bovina en el campo biomédico, se vio la necesidad de investigarla y comprenderla desde el punto de vista histórico. Aquí nos ocupamos de dicho aspecto en Medellín y Rionegro durante gran parte del siglo XX. La importancia y dinamismo de la ganadería en Antioquia en el siglo XX explican en parte la preocupación privada y oficial por mejorar esa actividad mediante la prevención de enfermedades. Desde 1914 surge una política sanitaria local interesada en el control de alimentos provenientes de la cría de animales. Al tiempo que crece la producción lechera, emergen la necesidad del control veterinario y la ense anza de la medicina veterinaria. Aunque la fasciolosis bovina se puede rastrear desde las primeras décadas del siglo XX, en los registros biomédico y sanitario de Medellín y Rionegro no aparece como preocupación prioritaria. Los estudios sobre esta enfermedad publicados en periódicos y revistas del país en la primera mitad del siglo XX circularon entre especialistas y no tuvieron incidencia en el sector ganadero. Incluso, la documentación de las últimas décadas del siglo XX sugiere que pese a la alta incidencia de la enfermedad, las investigaciones sobre fasciolosis no han tenido impacto en el desarrollo de programas para su prevención y control. In the approach of bovine fasciolosis biomedical studies, historical research has become necessary. Here we deal with the historical aspects in Medellín and Rionegro during most of XX century. The importance and dynamism of cattle activity in Antioquia during XX century partially explains private and official interests in improving this sector of economy through disease prevention. Since 1914, a local sanitary policy emerges, concerning control for food coming from animal brood. While milk production increases, the requirement of veterinary control and teaching appears in Colombia. Although bovine fasciolosis reports can be followed since the first decades of XX century, it does not appear as a main concern in biomedical and sanitary reports from Medellín and Rionegro. Studies regarding this disease, published in several national newspapers and journals from the first middle of XX century, circulated among specialists and did not have an influence in cattle in Colombia. Moreover, an evaluation of documents belonging to the last decades of XX century suggests that, despite the high disease incidence, fasciolosis research has not had an impact in the development of prevention and control programs.
DESARROLLO DE UN SEPARADOR DE OBJETOS DUROS EN EL CAFé A PARTIR DE LAS VIBRACIONES PRODUCIDAS EN PLACAS DELGADAS DEVELOPMENT OF A SEPARATOR IN THE COFFEE HARD OBJECTS FROM THE VIBRATIONS PRODUCED IN THIN PLATES
Diego Agudelo Gómez,Carlos Eugenio Oliveros Tascón,Jorge Hernán Estrada Estrada,Fernando álvarez Mejìa
Revista Facultad Nacional de Agronomía, Medellín , 2008,
Abstract: En Cenicafé se dise aron y construyeron prototipos electromecánicos denominados PESELOD (pescador electrónico de objetos duros) para la protección de las máquinas despulpadoras. Este nuevo módulo, localizado antes de la despulpadora, está conformado por un alimentador, un cuerpo vibrante (placa delgada o cono metálico), una compuerta, un recipiente para los objetos duros desalojados y un circuito para la detección y separación automática del objeto duro. Su principio de funcionamiento se basa en la diferencia de los parámetros de amplitud y frecuencia de las vibraciones producidas en el impacto del café y de los objetos duros contra el cuerpo vibrante. Se realizó el análisis histórico en los espectros de las aceleraciones que se indujeron teniendo en cuenta variaciones del material, espesor y apoyo. En la caracterización se encontraron mejores características de separación para placas de 2,5 mm de espesor, simplemente soportada y de material acerado. Los prototipos presentaron eficacias superiores al 80% y rendimientos entre 300 y 2.000 kg h-1 de café en cereza. De igual manera se realizaron variaciones tendientes a mejorar su operabilidad, relacionada con la limpieza de las placas para lo cual se construyó otro prototipo cuyo cuerpo vibrante lo constituía un cono acerado. Electromechanical experimental models of an electronic separator of hard objects, denominated PESELOD (pescador electrónico de objetos duros, Spanish) were designed and constructed in Cenicafé to protect the coffee processing machines. The module, located before the pulping machine, includes a feeder, a vibrant body (thin plate or metallic cone), a gate, a hard objects container and a circuit for both hard objects detection and automatic separation. Its principle of operation is based on the difference of amplitude and frequency of the vibrations produced by impact of coffee fruits and hard objects against a vibrant body. The historical analysis was made in the spectrums of the accelerations that were induced on different materials, thicknesses and boundary conditions. The device worked better with steel plates, 2.5 mm thick, simply supported. The model presented effectiveness greater than 80% and yields between 300 and 2.000 kg h-1 of coffee fruits. To improve their operability related to dirty plates, another model was constructed with a truncated cone vibrant body.
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