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Search Results: 1 - 10 of 206591 matches for " Oscar Julián Velásquez Ballesteros "
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Quantification, chemical and biological characterization of the saponosides material from Sida cordifolia L. (escobilla) Cuantificación, caracterización química y biológica del contenido saponósido de Sida cordifolia L. (escobilla)
Oscar Julián Velásquez Ballesteros,Elizabeth Murillo Perea,John Jairo Méndez,Walter Murillo Arango
Revista Cubana de Plantas Medicinales , 2013,
Abstract: Introduction: Sida cordifolia L. (Malvaceae) is a weed about which not much is known in Colombia. This plant is used in folk medicine to treat oral mucosa, blennorrhea, asthma and bronchitis.In Brazil it finds application as an anti-inflammatory,while in Colombia its "baba" is used for treating hair loss, constipation and internal fever, among other ailments. Objectives: to quantify the saponoside content and evaluate its antioxidant and antifungal functionality. Methods: we prepared organic, aqueous and hydroalcoholic extracts from the aerial section of the plant. The saponoside material was quantified by the DNS and p-anisaldehyde methods. The most concentrated extracts were selected for antioxidant and antifungal assays. Results: it was found that Sida cordifolia, collected in Ibague-Colombia, is a good source of saponins with diverse chemical structures, mainly of steroidal nature, some of which may be hecogenin, diosgenin or a homologue. Conclusions: these factors may contribute, at least in part, to the antioxidant and antifungal functionality of Sida cordifolia L., but this capacity may be modified if these saponins act independently or together with some other metabolites of the plant such as tannins, flavonoids steroids, and alkaloids among others. Introducción: Sida cordifolia L. (Malvaceae) es una hierba de la cual se tiene un conocimiento limitado en Colombia. Se utiliza en la medicina popular para el tratamiento de la mucosa oral, la blenorragia, el asma y la bronquitis. En Brasil encuentra aplicación como antiinflamatorio, mientras que en Colombia su "baba" se utiliza para tratar la pérdida del cabello, el estre imiento, y la fiebre interna, entre otros padecimientos. Objetivos: cuantificar el contenido saponósido y evaluar sus propiedades antioxidantes y funcionalidad antifúngica. Métodos: se prepararon extractos orgánicos, acuosos e hidroalcohólicos de la parte aérea de la planta. El material de saponósidos se cuantificó por los métodos del DNS (dinitrosalicylic acid reagent) y de p-anisaldehído. Los extractos más concentrados se seleccionaron para los ensayos antioxidante y antifúngico. Resultados: estos mostraron que Sida cordifolia, colectada en Ibague-Colombia, es una buena fuente de saponinas con diversas estructuras químicas, principalmente de naturaleza esteroidal, algunas de las cuales pueden ser hecogenina, diosgenina o un homólogo. Conclusiones: estos factores pueden contribuir, al menos en parte, en la funcionalidad antioxidante y antifúngica de Sida cordifolia L., pero su capacidad se puede modificar si esas saponinas actúan
Ampliación de anillo aórtico para implantación de prótesis: Evolución en el tiempo Aortic ring widening for prosthesis implantation: Evaluation throughout time
Oscar Velásquez,Néstor Sandoval,Hernando Orjuela,Hernando Santos
Revista Colombiana de Cardiología , 2005,
Abstract: Objetivo: describir las características cardíacas de pacientes sometidos a cambio valvular aórtico con ampliación del anillo para implantación de una prótesis mayor, mediante seguimiento clínico y ecocardiográfico. Materiales y métodos: entre 1997 y 2001 se tomaron 26 pacientes, de los cuales 13 (50%), con edad promedio de 57 a os, se sometieron a seguimiento. La ecocardiografía se practicó en el control, obteniéndose área valvular aórtica, masa ventricular y gradientes transprotésicos para luego establecer los índices respectivos. Resultados: hubo mejoría en la clase funcional de los 13 pacientes controlados, con 92.3% en clase I (p= 0.002). La evolución postoperatoria fue de 25 meses en promedio. El índice de masa ventricular y los gradientes valvulares (medio) presentaron reducción de 149 a 113 g/m2 y de 67 a 12.2 mm Hg respectivamente (p= 0.001); también se evidenció aumento en el índice de área efectiva valvular protésica que varió de 0.37 a 1 cm/m2 (p= 0.001). Discusión: los resultados evidencian involución en los trastornos ventriculares y mejoría en la clase funcional de los pacientes sometidos a este procedimiento; sin embargo, no se logró establecer comparación con pacientes que presentaran una prótesis menor a 21 mm de diámetro, lo que permitiría confirmar las ventajas de una válvula mayor. Conclusión: la cirugía de cambio valvular aórtico con ampliación del anillo para la implantación de una prótesis mayor, parece ser una alternativa para los pacientes con anillo aórtico nativo peque o, evidenciándose mejoría clínica y ecocardiográfica en su evolución. Objective: to describe the cardiac characteristics of patients submitted to aortic valvular change with ring widening for a bigger prosthesis implantation, through clinical and echocardiographic follow-up. Material and methods: 26 patients were chosen between 1997 and 2001. Follow-up was possible in 13 patients. Mean age was 57 years. A control echocardiogram was performed, obtaining the aortic valvular area, ventricular mass and the transprosthetic gradients in order to establish the respective index. Results: there was an improvement in the functional class of the controlled 13 patients, with 92.3% in class I (p: 0.002). Average postoperative evolution time was 25 months. Ventricular mass index and valvular gradients (Middle) showed a decrease from 149 to 113 gr/mt2 and from 67 to 12.2 mmHg respectively (p: 0.001). An increase in the efficient prosthetic valvular area was also evidenced; it varied from 0.37 to 1 cm/mt2 (p: 0.001). Discussion: the results evidence an involution of ventricular
Retrospective Descriptive Analysis of the Combined First Trimester of Pregnancy Screening in the Period Included from February 2016 to March 2017, Maternal Fetal Medicine Unit, San Juan de Dios Hospital  [PDF]
Carina Breuning Velásquez, Oscar Durán Soto, Joaquin Bustillos Villavicencio, Jorge Mora Sandí, Eugenio Calderon, Veronica Saborio, Leonardo Jimenez, Pablo Parra
Open Journal of Obstetrics and Gynecology (OJOG) , 2018, DOI: 10.4236/ojog.2018.810092
Abstract: A retrospective descriptive study is conducted at the San Juan de Dios Hospital, San José, Costa Rica, during the period from February 2016 to March 2017, with a total of 37 patients from which a combined screening during the first trimester of pregnancy was conducted, evaluating maternal age, biochemical and sonographic methods that together can predict the risk of fetal chromosomal alterations during pregnancy. The purpose of using combined screening as a noninvasive method is to identify high risk gestations and to minimize the number of invasive procedures to detect the highest number of cases. Four patients with higher risk of aneuploidy during pregnancy were identified through this screening.
Which statistics should tropical biologists learn?
Loaiza Velásquez,Natalia; González Lutz,María Isabel; Monge-Nájera,Julián;
Revista de Biología Tropical , 2011,
Abstract: tropical biologists study the richest and most endangered biodiversity in the planet, and in these times of climate change and mega-extinctions, the need for efficient, good quality research is more pressing than in the past. however, the statistical component in research published by tropical authors sometimes suffers from poor quality in data collection; mediocre or bad experimental design and a rigid and outdated view of data analysis. to suggest improvements in their statistical education, we listed all the statistical tests and other quantitative analyses used in two leading tropical journals, the revista de biología tropical and biotropica, during a year. the 12 most frequent tests in the articles were: analysis of variance (anova), chi-square test, student’s t test, linear regression, pearson’s correlation coefficient, mann-whitney u test, kruskal-wallis test, shannon’s diversity index, tukey’s test, cluster analysis, spearman’s rank correlation test and principal component analysis. we conclude that statistical education for tropical biologists must abandon the old syllabus based on the mathematical side of statistics and concentrate on the correct selection of these and other procedures and tests, on their biological interpretation and on the use of reliable and friendly freeware. we think that their time will be better spent understanding and protecting tropical ecosystems than trying to learn the mathematical foundations of statistics: in most cases, a well designed one-semester course should be enough for their basic requirements. rev. biol. trop. 59 (3): 983-992. epub 2011 september 01.
Amiloidosis cardiaca Cardiac amyloidosis
Mauricio Duque,Jorge E Velásquez,Jorge E Marín,Julián M Aristizábal
Revista Colombiana de Cardiología , 2009,
Abstract: La amiloidosis cardiaca es una manifestación de un grupo de enfermedades sistémicas que en conjunto se conocen como amiloidosis. Se considera una causa importante de las enfermedades infiltrativas que pueden ser responsables tanto del compromiso cardiaco como de otros órganos. Dado el avance en el entendimiento de la fisiopatología de la enfermedad, el reconocimiento de sus causas primarias y secundarias, y de las nuevas opciones terapéuticas, se describe un caso típico del compromiso cardiaco y posteriormente se hace una revisión del tema que abarca la mayoría de los tópicos que guardan relación con la amiloidosis primaria con compromiso cardiaco. Cardiac amyloidosis is a manifestation of a group of systemic diseases, known as amyloidosis. It is considered an important cause of infiltrative diseases that may be responsible for both the heart and other organs’ involvement. Given the progress in the understanding of the pathophysiology of the disease, the recognition of its primary and secondary causes and the new therapeutic options, a typical case of cardiac involvement is described and a review of the subject that covers the great majority of topics related to primary amyloidosis with cardiac involvement is made.
Which statistics should tropical biologists learn?
Natalia Loaiza Velásquez,María Isabel González Lutz,Julián Monge-Nájera
Revista de Biología Tropical , 2011,
Abstract: Tropical biologists study the richest and most endangered biodiversity in the planet, and in these times of climate change and mega-extinctions, the need for efficient, good quality research is more pressing than in the past. However, the statistical component in research published by tropical authors sometimes suffers from poor quality in data collection; mediocre or bad experimental design and a rigid and outdated view of data analysis. To suggest improvements in their statistical education, we listed all the statistical tests and other quantitative analyses used in two leading tropical journals, the Revista de Biología Tropical and Biotropica, during a year. The 12 most frequent tests in the articles were: Analysis of Variance (ANOVA), Chi-Square Test, Student’s T Test, Linear Regression, Pearson’s Correlation Coefficient, Mann-Whitney U Test, Kruskal-Wallis Test, Shannon’s Diversity Index, Tukey’s Test, Cluster Analysis, Spearman’s Rank Correlation Test and Principal Component Analysis. We conclude that statistical education for tropical biologists must abandon the old syllabus based on the mathematical side of statistics and concentrate on the correct selection of these and other procedures and tests, on their biological interpretation and on the use of reliable and friendly freeware. We think that their time will be better spent understanding and protecting tropical ecosystems than trying to learn the mathematical foundations of statistics: in most cases, a well designed one-semester course should be enough for their basic requirements. Rev. Biol. Trop. 59 (3): 983-992. Epub 2011 September 01. Los biólogos tropicales estudian la biodiversidad más rica y amenazada del planeta, y en estos tiempos de cambio climático y mega-extinción, la necesidad de investigación de buena calidad es más acuciante que en el pasado. Sin embargo, el componente estadístico en la investigación publicada por los autores tropicales adolece a veces de baja calidad en la toma de datos, mal dise o experimental y una visión anticuada del análisis de datos. Para sugerir mejoras en la ense anza de la estadística, hicimos una lista de todas las pruebas estadísticas y otros análisis cuantitativos aplicados en dos de las principales revistas tropicales, la Revista de Biología Tropical y Biotropica, durante un a o. Las 12 pruebas más frecuentes en los artículos fueron: Análisis de Varianza (ANDEVA), Chi-cuadrado, t de Student, Regresión lineal, Coeficiente de Correlación de Pearson, U de Mann-Whitney, Kruskal-Wallis, índice de diversidad de Shannon, Prueba de Tukey, Análisis de Conc
Fibrilación auricular: una mirada actual Atrial fibrillation: a current view
Julián Aristizábal,William Uribe,Eduardo Medina,Jorge E Velásquez
Revista Colombiana de Cardiología , 2012,
Abstract: La fibrilación auricular es la arritmia más frecuente en la práctica clínica y conlleva implicaciones significativas en la morbilidad y mortalidad cardiovascular de la población, así como en los costos para los sistemas de salud. No obstante, el conocimiento de la fisiopatología de la arritmia y el surgimiento de nuevas alternativas terapéuticas han cambiado la perspectiva en el manejo de esta enfermedad. Se realiza una revisión del desarrollo reciente en conceptos etiológicos y fisiológicos de la arritmia, así como en los esquemas de clasificación y evaluación del riesgo trombohemorrágico, además de los nuevos avances en terapias farmacológicas e intervencionistas. Atrial fibrillation is the most common arrhythmia in clinical practice and carries significant implications in the population's cardiovascular morbidity and mortality as well as in costs for the health systems. However, the knowledge of the pathophysiology of the arrhythmia and the emergence of new alternative therapies have changed the perspective in the management of this disease. We realize a review of recent developments in etiological and physiological concepts of the arrhythmia, as well as a review of the classification schemes and thrombohemorrhagic risk assessment in addition to the new advances in pharmacological and interventional therapies.
Elevación diafragmática con colapso de la aurícula derecha y síntomas de falla cardíaca: reporte de un caso Diaphragmatic elevation with collapse of the right atrium and symptoms of heart failure: a case report
Juan C Díaz,Mauricio Duque,Julián M Aristizábal,Jorge E Velásquez
Revista Colombiana de Cardiología , 2013,
Abstract: La elevación diafragmática es una entidad caracterizada por la alteración en la fuerza contráctil de las fibras musculares del diafragma, que conlleva prolapso de las estructuras abdominales hacia la cavidad torácica. En la mayoría de los casos, los síntomas se presentan por la compresión del parénquima pulmonar subyacente; la compresión de estructuras cardíacas es menos frecuente. Se reporta el caso de una paciente que presentó signos y síntomas compatibles con falla cardíaca derecha y en quien los diferentes estudios demostraron una elevación diafragmática con colapso de la aurícula derecha como causa de su sintomatología. Diaphragmatic elevation is a disorder characterized by impaired contractile force of the muscle fibers of the diaphragm, which results in prolapse of abdominal structures into the chest cavity. In most cases, symptoms occur by the underlying lung parenchyma compression. The compression of cardiac structures is less frequent. We report the case of a female patient who developed signs and symptoms consistent with right heart failure and in whom several studies showed a diaphragmatic elevation with collapse of the right atrium as cause of her symptomatology.
Hacia una Metodología para la Construcción de Modelos de Simulación Basados en Sistemas Multi-Agente.
Julián Moreno Cadavid,Juan David Velásquez Henao,Demetrio Ovalle Carranza
Avances en Sistemas e Informática , 2005,
Abstract: The aim of this paper is to show the different phases, models and artifacts of a methodology that was created by the research group in order to develop multi-agent based simulation models. The proposed methodology is based on some of the most outstanding features of the classic software engineering, the agent-oriented software engineering and the systems simulation. Once those features have been integrated we obtain a robust and well formalized methodology which could be applied in simulating social, economic, political, or even environmental models.
Implementación de una nariz electrónica para detectar pacientes con EPOC desde el aliento exhalado
Durán Acevedo,Cristhian Manuel; Velásquez Carvajal,Adriana Eugenia; Gualdron Guerrero,Oscar Eduardo;
Ingeniería y Desarrollo , 2012,
Abstract: this article presents the implementation of an electronic nose (en) based on the development of a measuring chamber composed of a matrix of 6 metal oxide gas sensors with partially overlapping sensitivities, to identify and classify the volatiles emitted from the exhaled breath of a group of healthy people and another group with samples of patients with chronic obstructive pulmonary disease (copd). a set of algorithms for pre-processing and signal processing based on techniques of feature extraction and statistical methods as principal component analysis (pca), for pattern recognition of data set were implemented. from the exhalation breath samples of these patients, the results were important, due to the classification of the patients with the disease as well as of the healthy voluntary group.
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