Oxidative stress induces DNA strand breaks may lead to genomic instability in ovarian tumorigenesis

Oxidative stress (OS) occurs when DNA repair mechanisms are overcome by the amount of single and double strand DNA breaks caused by an accumulation of reactive oxygen species (ROS). Genomic instability (GI) by microsatellite instability (MSI) accumulation is characterized by changes in DNA single tandem repeats (STR) as a direct result of ROS. Deregulation of DNA repair and tumor suppressor pathways have been described as causes of tumor progression and metastasis. Studies in mammals have focused on GI and the implications of increased mutation frequency due to accumulation of MSI leading to development of diseases, including infertility and cancer. Ovarian cancer is a deadly disease displaying the highest mortality rate among gynecological cancers. Hereditary ovarian cancer displays GI that can be established early in primordial germinal cells (PCGs) development and migration across the genital ridge, where PGCs are exposed to ROS damage. The hypothesis of this study was ROS-induced GI is marked by the accumulation of MSI on repetitive sequences of DNA that override DNA repair, tumor suppressor and redox homeostasis pathways. In this study, we induced ROS in human ovarian cell lines by hydrogen peroxide (H2O2) exposure, as well as evaluated mouse PGCs to determine whether MSI occurs in specific regions of human and mouse genomes. Our results show that MSI was present in specific markers after ROS-induced damage in human ovarian cells and in mouse Sod1 knockout PGCs during cell migration, both of which accumulate specific mutations caused by free radical damage. Ovarian tumor cells and mouse PGCs showed an increase of MSI in 12 human and 5 mouse repetitive markers that are located near important genes related to DNA repair, tumor suppression, cell proliferation, apoptosis and differentiation. This could be a signal that leads to tumor initiation, formation and progression in adult ovarian cells due to improper DNA repair and tumor suppression mechanisms or in disruption of PGC migration that determines germinal cell pool selection during early embryonic development due to absence of cell antioxidant mechanisms. Therefore, these specific unstable STRs are novel biomarkers that could be useful in early diagnostics, prognosis, and successful therapy of ovarian tumorigenesis

Oxidative stress induces DNA strand breaks may lead to genomic instability in ovarian tumorigenesis

Oxidative stress (OS) occurs when DNA repair mechanisms are overcome by the amount of single and double strand DNA breaks caused by an accumulation of reactive oxygen species (ROS). Genomic instability (GI) by microsatellite instability (MSI) accumulation is characterized by changes in DNA single tandem repeats (STR) as a direct result of ROS. Deregulation of DNA repair and tumor suppressor pathways have been described as causes of tumor progression and metastasis. Studies in mammals have focused on GI and the implications of increased mutation frequency due to accumulation of MSI leading to development of diseases, including infertility and cancer. Ovarian cancer is a deadly disease displaying the highest mortality rate among gynecological cancers. Hereditary ovarian cancer displays GI that can be established early in primordial germinal cells (PCGs) development and migration across the genital ridge, where PGCs are exposed to ROS damage. The hypothesis of this study was ROS-induced GI is marked by the accumulation of MSI on repetitive sequences of DNA that override DNA repair, tumor suppressor and redox homeostasis pathways. In this study, we induced ROS in human ovarian cell lines by hydrogen peroxide (H2O2) exposure, as well as evaluated mouse PGCs to determine whether MSI occurs in specific regions of human and mouse genomes. Our results show that MSI was present in specific markers after ROS-induced damage in human ovarian cells and in mouse Sod1 knockout PGCs during cell migration, both of which accumulate specific mutations caused by free radical damage. Ovarian tumor cells and mouse PGCs showed an increase of MSI in 12 human and 5 mouse repetitive markers that are located near important genes related to DNA repair, tumor suppression, cell proliferation, apoptosis and differentiation. This could be a signal that leads to tumor initiation, formation and progression in adult ovarian cells due to improper DNA repair and tumor suppression mechanisms or in disruption of PGC migration that determines germinal cell pool selection during early embryonic development due to absence of cell antioxidant mechanisms. Therefore, these specific unstable STRs are novel biomarkers that could be useful in early diagnostics, prognosis, and successful therapy of ovarian tumorigenesis

El papel de las fiestas en la revalorización del pulque, una bebida ancestral del centro de México

Artículo original de investigaciónAnalizamos el papel que cumplen las fiestas en la preservación y revalorización del pulque, una bebida fermentada ancestral del centro de México. Para ello, se acudió a fuentes secundarias y testimonios de informantes clave, a fin de identificar y caracterizar las principales fiestas en las que el pulque tiene una alta presencia. La aproximación del estudio fue cualitativa y exploratoria. Se identificaron dos tipos de fiestas: fiestas de alta tradición popular y fiestas emanadas de la neocultura del pulque. Las primeras se realizan mediante una lógica de consumo tradicional, con un significado religioso, histórico y cultural, más próximas al concepto de festividad. Las segundas, por su parte, ocurren bajo una lógica de neoconsumo, basada en la búsqueda de identidad en las sociedades globalizadas, con un talante comercial, ajustadas a escalas de producción industrial y más próximas al concepto de feria. Se concluye que el pulque preserva y revaloriza a pesar de la adversidad de los contextos económicos, políticos y culturales que lo circundan, debido a un proceso de valorización social en el que ambos tipos de fiestas contribuyen notablemente. Para ampliar los beneficios de los participantes en la cadena de valor de la agroindustria del pulque, se recomienda generar consensos para que ambos tipos de fiestas coexistan, destacando la riqueza específica de cada tipo y permitiendo a consumidores tradicionales y nuevos apreciar diferentes significados en la bebida

Tamaño de planta y formación específica en el mercado laboral colombiano

Con base en la Encuesta de Calidad de Vida (ECV) de 2003 del DANE, en este trabajo se estudia la formación para el empleo (FPE) en el mercado laboral colombiano. Se encuentra una relación estrecha entre modernidad empresarial y FPE. Utilizando funciones mincerianas modificadas se encuentra que la rentabilidad de la FPE aumenta con el nivel de educación formal y el tamaño de las empresas

Impacto socio ambiental de la calidad del agua del río Portoviejo en el período 2014-2017

The present paper evaluates the environmental partner impacts negative caused by the pollution of the Portoviejo river water in the province of Manabí, Ecuador. Several studies developed on this problem indicate that the dumping of wastewater on its channel, the unplanned human settlements on its banks and the dumping of solid waste have caused the gradual deterioration of this important natural effluent. The results obtained show that having a poor quality water has high costs for the treatment of water used for human consumption, which is assumed by the population in the consumption payments for this service, to this is added the agricultural production in the area and the need to implement an environmental management plan for the collection and final disposal of solid waste generated by the population, as well as to evaluate the operation of the wastewater treatment plant of the city of Portoviejo.El presente trabajo evalúa los impactos socio ambientales negativos causados por la contaminación del agua del río Portoviejo en la provincia de Manabí, Ecuador. Varios estudios desarrollados sobre esta problemática indican que el vertimiento de aguas residuales sobre su cauce, los asentamientos humanos no planificados en sus riveras y el vertimiento de desechos sólidos, han provocado el deterioro paulatino de este importante efluente natural. Los resultados obtenidos demuestran que el tener un agua de mala calidad incide en elevados costos para el tratamiento del agua utilizada para consumo humano, el mismo que es asumido por la población en los pagos de consumo por este servicio, a esto se adiciona la no producción agrícola en la zona y la necesidad de poder implementar un plan de manejo ambiental para la recolección y disposición final de los desechos sólidos generados por la población, así como de evaluar el funcionamiento de la planta de tratamiento de aguas residuales de la ciudad de Portoviejo

Experimental Matching of Instances to Heuristics for Constraint Satisfaction Problems

Constraint satisfaction problems are of special interest for the artificial intelligence and operations research community due to their many applications. Although heuristics involved in solving these problems have largely been studied in the past, little is known about the relation between instances and the respective performance of the heuristics used to solve them. This paper focuses on both the exploration of the instance space to identify relations between instances and good performing heuristics and how to use such relations to improve the search. Firstly, the document describes a methodology to explore the instance space of constraint satisfaction problems and evaluate the corresponding performance of six variable ordering heuristics for such instances in order to find regions on the instance space where some heuristics outperform the others. Analyzing such regions favors the understanding of how these heuristics work and contribute to their improvement. Secondly, we use the information gathered from the first stage to predict the most suitable heuristic to use according to the features of the instance currently being solved. This approach proved to be competitive when compared against the heuristics applied in isolation on both randomly generated and structured instances of constraint satisfaction problems

Protoindustrialización, industrialización y desindustrialización en la historia de México

1 archivo PDF (292 páginas)Conjunto de trabajos que lo mismo buscan identificar embriones de industrialización que apuntar los vaivenes de este proceso a lo largo del siglo XIX como abordar las políticas de fomento a la industrialización que la impulsan a lo largo de la primera mitad del siglo XX, así como el desmantelamiento industrial que se vive con una nueva fase de desarrollo con características neoliberales en un contexto de globalización que exige recuperar la memoria en el tiempo largo para sacar de ella nuevas alternativas de desarrollo y formas de organización productiva. En esta perspectiva, da cuenta de algunas experiencias protoindustriales e industriales en sectores que, en su momento, fueron claves para la economía de la colonia y posterionnente en el México Independiente: minería, textiles, azúcar, manufacturas así como las oportunidades que abre un nuevo orden económico signado por la informática