73 research outputs found

    Evaluación de la eficacia de la angioplastia transluminal percutánea en pacientes con isquemia crónica de miembros inferiores

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    El presente trabajo tiene como propósito demostrar la utilidad de la angioplastia transluminal percutánea (ATP) como una opción terapéutica en pacientes con isquemia crítica de miembros inferiores (MsIs). Se realizó un estudio descriptivo retrospectivo con serie de casos. Durante un período de 33 meses, entre mayo de 2008 y enero de 2011, fueron tratados por vía endovascular por medio de ATP como primera opción terapéutica, 46 pacientes, de los cuales fueron 26 hombres (56%) y 20 mujeres (44%) con isquemia crítica de MsIs según clasificación de Fontaine (grados III y IV), no revascularizables quirúrgicamente. El manejo y control postoperatorio fueron realizados por un grupo de especialistas en Cirugía Vascular y Radiología Intervencionista durante un periodo de 3 meses. El estudio permitió determinar que la ATP, es una excelente opción terapéutica de primera elección en pacientes con isquemia crítica de MsIs que tienen un elevado riesgo de amputació

    The carbon footprint of beef transportation in Colombia: Market connections and distribution networks

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    Livestock food systems largely contribute to the overall food systems’ greenhouse gas (GHG) emissions and are thus put at the centre of global policy and research agendas on mitigation and adaptation. An additional growing concern on the prevalence of globalised animal product value chains and the specialisation of agricultural markets and their environmental pressures over supply networks further adds to this debate. However, detailed quantification of the livestock contribution intensity to the emissions has focused mostly on the farm and the performance of animals’ feed intake, rather than on the composition and extension of the beef supply network, a perspective that contributes to further our understanding of the food system’s carbon footprint. This research thus used the calculation of food miles to explore the functioning of the Colombian beef market and the emissions entailed in the mobilisation of live animals and processed products in central trade nodes between 2019-2022. The results were compared with emissions derived from the transportation of alternative proteins from animal (chicken, pork, eggs, and milk) and non-animal sources (dry grains). The analysis of bovine products indicates that beef transport was responsible for the highest environmental load, generating on average 25.000 tons CO2eq, in contrast to alternative proteins, where chicken meat is the biggest culprit (40.000 tons CO2eq). However, chicken’s growing demand has increased the quantities mobilised compared to beef, reflecting a greater efficiency of the chicken supply network per volume mobilised. The relational pattern observed in Colombia’s regions pointed out Cali as the leading city in the reception and redistribution of live animals and beef. A strong interaction with neighbouring municipalities in the southwest and the Colombian Amazon configures Cali as a highly central node that, in consequence, concentrates significant pollution. These findings reveal the need to develop comprehensive approaches and strategies to reduce livestock production emissions, acknowledging the vital role that the beef supply network, transportation distances, infrastructure, and technologies play in cattle-derived emissions

    The Involvement of Peripheral and Brain Insulin Resistance in Late Onset Alzheimer's Dementia

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    Nowadays, Alzheimer's disease (AD) is a severe sociological and clinical problem. Since it was first described, there has been a constant increase in its incidence and, for now, there are no effective treatments since current approved medications have only shown short-term symptomatic benefits. Therefore, it is imperative to increase efforts in the search for molecules and non-pharmacological strategies that are capable of slowing or stopping the progress of the disease and, ideally, to reverse it. The amyloid cascade hypothesis based on the fundamental role of amyloid has been the central hypothesis in the last 30 years. However, since amyloid-directed treatments have shown no relevant beneficial results other theories have been postulated to explain the origin of the pathology. The brain is a highly metabolically active energy-consuming tissue in the human body. It has an almost complete dependence on the metabolism of glucose and uses most of its energy for synaptic transmission. Thus, alterations on the utilization or availability of glucose may be cause for the appearance of neurodegenerative pathologies like AD. In this review article, the hypothesis known as Type 3 Diabetes (T3D) will be evaluated by summarizing some of the data that has been reported in recent years. According to published research, the adherence over time to low saturated fatty acids diets in the context of the Mediterranean diet would reduce the inflammatory levels in brain, with a decrease in the pro-inflammatory glial activation and mitochondrial oxidative stress. In this situation, the insulin receptor pathway would be able to fine tune the mitochondrial biogenesis in neuronal cells, regulation the adenosine triphosphate/adenosine diphosphate intracellular balance, and becoming a key factor involved in the preservation of the synaptic connexions and neuronal plasticity. In addition, new targets and strategies for the treatment of AD will be considered in this review for their potential as new pharmacological or non-pharmacological approaches

    Efecto del antioxidante natural Vimang sobre las características histopatológicas gingivales en la enfermedad periodontal experimental

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    El Vimang es un extracto de la corteza del árbol Mangifera indica L. con propiedades antioxidantes y antinflamatorias. Por ello, nos propusimos evaluar su efecto sobre las características histopatológicas de la encía, en un modelo de enfermedad periodontal. Se colocaron ligaduras en el surco gingival de dos dientes de las hemiarcadas superiores derechas, a diez perros Beagles . A cinco de ellos, seleccionados al azar, se les aplicó localmente una solución de Vimang a 1%, dos veces al día; a los otros, se les aplicó el vehículo. A los 21 días, se tomaron muestras gingivales de los dientes en estudio y se procesaron para su evaluación histopatológica. La aplicación del extracto disminuyó el grado de infiltrado inflamatorio crónico y de hiperplasia del epitelio del surco gingival, en las encías de los dientes ligados. Se concluye que el Vimang atenúa la inflamación gingival en el modelo de enfermedad periodontal por ligadura en perros.Palabras clave: Periodontitis, Vimang, antioxidantes, ligadura, perros.</p

    Desarrollo de una plataforma computacional para el modelado metabólico de microorganismos

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    La Biología Sintética (BS) se centra en el diseño y la construcción de sistemas genéticos artificiales, capaces de desarrollar una función específica después de haber sido introducidos en un sistema vivo. Con el desarrollo de la BS, se observa una nueva generación de bioingenieros que desarrollan complejos circuitos biológicos genéticos con un alto nivel de integración. La mejora de esta disciplina científica tiene por objeto establecer un marco computacional y conceptual que dé asistencia al desarrollo de sistemas biológicos artificiales modulares basándose en una metodología ingenieril y sistemática, para lo que se necesita proveer a la próxima generación de diseñadores en Biología Sintética y a los futuros biotecnólogos e ingenieros biológicos de nuevas herramientas computacionales integradas en un entorno común para el análisis de fenotipos metabólicos, el diseño de nuevos circuitos genéticos complejos y la visualización de mapas metabólicos. Como resultado de esta investigación se obtiene la plataforma Hydra (Hybrid Draw and Routes Analysis), que integra diversas herramientas para el diseño, análisis y visualización de las redes metabólicas.Synthetic biology focuses on the design and construction of artificial genetic systems that are capable of carrying out a specific function after being inserted into a living system. With the development of synthetic biology a new generation of bioengineers has appeared who develop complex, highly integrated genetic biological pathways. The improvement of this scientific discipline aims to establish a computational and conceptual framework that will support the development of modular artificial biological systems based on an engineering and systematic methodology. To achieve this, it will be necessary to provide new integrated computational tools in a common environment for the analysis of metabolic phenotypes, the design of new complex genetic pathways and the visualisation of metabolic maps to the next generation of designers in synthetic biology and future biotechnologists and biological engineers. A result of this research is the Hydra platform (Hybrid Draw and Routes Analysis) that integrates various tools for the design, analysis, and visualisation of metabolic networks.Ciencias Experimentale

    Thermodynamics, transport and relaxation in non-conformal theories

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    We study the equilibrium and near-equilibrium properties of a holographic five-dimensional model consisting of Einstein gravity coupled to a scalar field with a non-trivial potential. The dual four-dimensional gauge theory is not conformal and, at zero temperature, exhibits a renormalisation group flow between two different fixed points. We quantify the deviations from conformality both in terms of thermodynamic observables and in terms of the bulk viscosity of the theory. The ratio of bulk over shear viscosity violates Buchel's bound. We study relaxation of small-amplitude, homogeneous perturbations by computing the quasi-normal modes of the system at zero spatial momentum. In this approximation we identify two different relaxation channels. At high temperatures, the different pressures first become approximately equal to one another, and subsequently this average pressure evolves towards the equilibrium value dictated by the equation of state. At low temperatures, the average pressure first evolves towards the equilibrium pressure, and only later the different pressures become approximately equal to one another

    International study to evaluate PCR methods for detection of Trypanosoma cruzi DNA in blood samples from Chagas disease patients

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    A century after its discovery, Chagas disease, caused by the parasite Trypanosoma cruzi, still represents a major neglected tropical threat. Accurate diagnostics tools as well as surrogate markers of parasitological response to treatment are research priorities in the field. The polymerase chain reaction (PCR) has been proposed as a sensitive laboratory tool for detection of T. cruzi infection and monitoring of parasitological treatment outcome. However, high variation in accuracy and lack of international quality controls has precluded reliable applications in the clinical practice and comparisons of data among cohorts and geographical regions. In an effort towards harmonization of PCR strategies, 26 expert laboratories from 16 countries evaluated their current PCR procedures against sets of control samples, composed by serial dilutions of T.cruzi DNA from culture stocks belonging to different lineages, human blood spiked with parasite cells and blood samples from Chagas disease patients. A high variability in sensitivities and specificities was found among the 48 reported PCR tests. Out of them, four tests with best performance were selected and further evaluated. This study represents a crucial first step towards device of a standardized operative procedure for T. cruzi PCR.Fil: Schijman, Alejandro G. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET). Laboratorio de Biología Molecular de la Enfermedad de Chagas (LabMECh); Argentina.Fil: Bisio, Margarita. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET). Laboratorio de Biología Molecular de la Enfermedad de Chagas (LabMECh); Argentina.Fil: Orellana, Liliana. Universidad de Buenos Aires. Instituto de Cálculo; Argentina.Fil: Sued, Mariela. Universidad de Buenos Aires. Instituto de Cálculo; Argentina.Fil: Duffy, Tomás. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET). Laboratorio de Biología Molecular de la Enfermedad de Chagas (LabMECh); Argentina.Fil: Mejia Jaramillo, Ana M. Universidad de Antioquia. Grupo Chagas; Colombia.Fil: Cura, Carolina. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET). Laboratorio de Biología Molecular de la Enfermedad de Chagas (LabMECh); Argentina.Fil: Auter, Frederic. French Blood Services; Francia.Fil: Veron, Vincent. Universidad de Parasitología. Laboratorio Hospitalario; Guayana Francesa.Fil: Qvarnstrom, Yvonne. Centers for Disease Control. Department of Parasitic Diseases; Estados Unidos.Fil: Deborggraeve, Stijn. Institute of Tropical Medicine; Bélgica.Fil: Hijar, Gisely. Instituto Nacional de Salud; Perú.Fil: Zulantay, Inés. Facultad de Medicina; Chile.Fil: Lucero, Raúl Horacio. Universidad Nacional del Nordeste; Argentina.Fil: Velázquez, Elsa. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología Dr. Mario Fatala Chaben; Argentina.Fil: Tellez, Tatiana. Universidad Mayor de San Simon. Centro Universitario de Medicina Tropical; Bolivia.Fil: Sanchez Leon, Zunilda. Universidad Nacional de Asunción. Instituto de Investigaciones en Ciencias de la Salud; Paraguay.Fil: Galvão, Lucia. Faculdade de Farmácia; Brasil.Fil: Nolder, Debbie. Hospital for Tropical Diseases. London School of Tropical Medicine and Hygiene Department of Clinical Parasitology; Reino Unido.Fil: Monje Rumi, María. Universidad Nacional de Salta. Laboratorio de Patología Experimental; Argentina.Fil: Levi, José E. Hospital Sirio Libanês. Blood Bank; Brasil.Fil: Ramirez, Juan D. Universidad de los Andes. Centro de Investigaciones en Microbiología y Parasitología Tropical; Colombia.Fil: Zorrilla, Pilar. Instituto Pasteur; Uruguay.Fil: Flores, María. Instituto de Salud Carlos III. Centro de Mahahonda; España.Fil: Jercic, Maria I. Instituto Nacional De Salud. Sección Parasitología; Chile.Fil: Crisante, Gladys. Universidad de los Andes. Centro de Investigaciones Parasitológicas J.F. Torrealba; Venezuela.Fil: Añez, Néstor. Universidad de los Andes. Centro de Investigaciones Parasitológicas J.F. Torrealba; Venezuela.Fil: De Castro, Ana M. Universidade Federal de Goiás. Instituto de Patologia Tropical e Saúde Pública (IPTSP); Brasil.Fil: Gonzalez, Clara I. Universidad Industrial de Santander. Grupo de Inmunología y Epidemiología Molecular (GIEM); Colombia.Fil: Acosta Viana, Karla. Universidad Autónoma de Yucatán. Departamento de Biomedicina de Enfermedades Infecciosas y Parasitarias Laboratorio de Biología Celular; México.Fil: Yachelini, Pedro. Universidad Católica de Santiago del Estero. Instituto de Biomedicina; Argentina.Fil: Torrico, Faustino. Universidad Mayor de San Simon. Centro Universitario de Medicina Tropical; Bolivia.Fil: Robello, Carlos. Instituto Pasteur; Uruguay.Fil: Diosque, Patricio. Universidad Nacional de Salta. Laboratorio de Patología Experimental; Argentina.Fil: Triana Chavez, Omar. Universidad de Antioquia. Grupo Chagas; Colombia.Fil: Aznar, Christine. Universidad de Parasitología. Laboratorio Hospitalario; Guayana Francesa.Fil: Russomando, Graciela. Universidad Nacional de Asunción. Instituto de Investigaciones en Ciencias de la Salud; Paraguay.Fil: Büscher, Philippe. Institute of Tropical Medicine; Bélgica.Fil: Assal, Azzedine. French Blood Services; Francia.Fil: Guhl, Felipe. Universidad de los Andes. Centro de Investigaciones en Microbiología y Parasitología Tropical; Colombia.Fil: Sosa Estani, Sergio. ANLIS Dr.C.G.Malbrán. Centro Nacional de Diagnóstico e Investigación en Endemo-Epidemias; Argentina.Fil: DaSilva, Alexandre. Centers for Disease Control. Department of Parasitic Diseases; Estados Unidos.Fil: Britto, Constança. Instituto Oswaldo Cruz/FIOCRUZ. Laboratório de Biologia Molecular e Doenças Endêmicas; Brasil.Fil: Luquetti, Alejandro. Laboratório de Pesquisa de Doença de Chagas; Brasil.Fil: Ladzins, Janis. World Health Organization (WHO). Special Programme for Research and Training in Tropical Diseases (TDR); Suiza

    International Study to Evaluate PCR Methods for Detection of Trypanosoma cruzi DNA in Blood Samples from Chagas Disease Patients

    Get PDF
    A century after its discovery, Chagas disease, caused by the parasite Trypanosoma cruzi, still represents a major neglected tropical threat. Accurate diagnostics tools as well as surrogate markers of parasitological response to treatment are research priorities in the field. The polymerase chain reaction (PCR) has been proposed as a sensitive laboratory tool for detection of T. cruzi infection and monitoring of parasitological treatment outcome. However, high variation in accuracy and lack of international quality controls has precluded reliable applications in the clinical practice and comparisons of data among cohorts and geographical regions. In an effort towards harmonization of PCR strategies, 26 expert laboratories from 16 countries evaluated their current PCR procedures against sets of control samples, composed by serial dilutions of T.cruzi DNA from culture stocks belonging to different lineages, human blood spiked with parasite cells and blood samples from Chagas disease patients. A high variability in sensitivities and specificities was found among the 48 reported PCR tests. Out of them, four tests with best performance were selected and further evaluated. This study represents a crucial first step towards device of a standardized operative procedure for T. cruzi PCR

    Reconstructing Native American Population History

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    The peopling of the Americas has been the subject of extensive genetic, archaeological and linguistic research; however, central questions remain unresolved1–5. One contentious issue is whether the settlement occurred via a single6–8 or multiple streams of migration from Siberia9–15. The pattern of dispersals within the Americas is also poorly understood. To address these questions at higher resolution than was previously possible, we assembled data from 52 Native American and 17 Siberian groups genotyped at 364,470 single nucleotide polymorphisms. We show that Native Americans descend from at least three streams of Asian gene flow. Most descend entirely from a single ancestral population that we call “First American”. However, speakers of Eskimo-Aleut languages from the Arctic inherit almost half their ancestry from a second stream of Asian gene flow, and the Na-Dene-speaking Chipewyan from Canada inherit roughly one-tenth of their ancestry from a third stream. We show that the initial peopling followed a southward expansion facilitated by the coast, with sequential population splits and little gene flow after divergence, especially in South America. A major exception is in Chibchan-speakers on both sides of the Panama Isthmus, who have ancestry from both North and South America

    Taxonomy based on science is necessary for global conservation

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