Cuatro fragmentos para una antireflexión

El espíritu ilustrado ha dejado como herencia al entendimiento del hombre de ciencia contemporáneo, la idea de que todo lo que es susceptible de ser conocido puede ser subordinado a una ley; en sintonía con estos criterios cosmovisivos, a partir del positivismo se ha postulado que sólo posee densidad ontológica aquello que puede ser conocido mediante el método científico. Pero por fuera del ímpetu legalista de la ilustración y de la tradición metodológica del positivismo, la historia nos muestra tradiciones cuyos criterios para determinar las rutas de conocimiento que ha de seguir la inteligencia humana, no sólo contemplan lógicas rigurosas sino disciplinas éticas y estéticas

Computación grid

La monografía “COMPUTACIÓN GRID”, responde a la necesidad de investigación, divulgación y formación en esta tecnología basada en el aprovechamiento de recursos subutilizados por gran cantidad de equipos conectados a la Red, permitiendo abordar y solucionar tareas que son demasiado exigentes para una sola máquina y además, el trabajo cooperativo a nivel global. Fue elaborado entre los meses de noviembre de 2010 y mayo del año 2011 por estudiantes del Programa de Ingeniería Electrónica en La Universidad Tecnológica de Bolívar, que cursan El Minor en Telecomunicaciones requisito para optar al título. El trabajo integra la consulta, recopilación, comparación y concreción de datos sobre el tema con la descripción final o tratado en el cual se muestra las bases teóricas y evolución histórica de la computación GRID con el fin de informar sobre los avances, ventajas y posibilidades que provee para que sean conocidos y evaluados. Paralelamente, la monografía busca que dicha tecnología sea implementada en nuevas aplicaciones que repotencialicen su funcionalidad. La metodología de trabajo fue la pertinente con la investigación bibliográfica y los objetivos responden a la necesidad de tener una fuente de consulta sobre “Computación GRID” de fácil comprensión y libre acceso. Esta necesidad fue arrojada por la selección temática realizada entre las opciones propuestas por el director del programa.Incluye anexos, bibliografí

Avaliação de métodos para inoculação e diagnóstico de vírus de mosaico do pepino (CMV)

The Cucumber mosaic virus (CMV) is a limiting agent in the production and quality of agricultural crops; whose effective inoculation and reliable diagnosis are essential to implement suitable and timely management strategies. Two protocols for CMV inoculation in Nicotiana benthamiana and N. tabacum cv. Xanthi as indicator plants and different virus detection methods were evaluated. Infection of plants with CMV was achieved by mechanical transmission and infiltration. The presence of the virus was confirmed by expression of symptoms, serology (ImmunoStrip®), RT-PCR and by sequencing. The results confirmed the effectiveness of the mechanical transmission. The infected plants showed symptoms associated with the pathogen 15 days after inoculation. The serological test allowed detecting the presence of the pathogen only in N. benthamiana plants, while the RT-PCR test in all evaluated plants. The sequencing results showed high nucleotide identity values with the sequences reported in the NBCI for this virus. Mechanical transmission was the most effective method for CMV inoculation, and molecular analysis techniques were more sensitive and reliable for CMV identification, compared to serological test.El virus del mosaico del pepino (CMV) es un agente limitante en la producción y calidad de cultivos agrícolas; cuya inoculación efectiva y diagnóstico confiable son esenciales para implementar estrategias de manejo adecuadas y oportunas. Se evaluaron dos protocolos para la inoculación del CMV en plantas indicadoras (Nicotiana benthamiana y N. tabacum cv. Xanthi) y diferentes métodos de detección de este virus. La infección de plantas con CMV se logró mediante transmisión mecánica e infiltración. La presencia del virus se confirmó mediante la expresión de síntomas, serología (ImmunoStrip®), RT-PCR y por secuenciación. Los resultados confirmaron la efectividad del método de transmisión mecánica, en el cual, las plantas infectadas presentaron sintomatología asociada con el virus 15 días después de su inoculación. La prueba serológica permitió detectar la presencia del patógeno solo en las plantas de N. benthamiana, mientras que la prueba de RT-PCR en todas las plantas evaluadas. Los resultados de secuenciación mostraron altos valores de identidad nucleotídica con las secuencias reportadas en el NCBI para este virus. La transmisión mecánica fue el método más efectivo para la inoculación del CMV y las técnicas de análisis molecular fueron más sensibles y confiables para su identificación, en comparación con la prueba serológica.O vírus do mosaico do pepino (CMV) é um agente limitante na produção e qualidade das culturas agrícolas, cuja inoculação eficaz e diagnóstico confiável são essenciais para implementar estratégias de manejo adequadas e oportunas. Foram avaliados dois protocolos de inoculação de CMV em plântulas indicadoras (Nicotiana benthamiana e N. tabacum cv. Xanthi) e diferentes métodos de detecção do vírus. A infecção com CMV foi obtida por transmissão mecânica e por infiltração. A presença do vírus foi confirmada pela expressão dos sintomas, serologia (ImmunoStrip®), RT-PCR e sequenciamento. Os resultados confirmaram a eficácia da transmissão mecânica, no qual plântulas infectadas apresentaram sintomas associados ao vírus 15 dias após a inoculação. O teste serológico permitiu detectar a presença do patógeno apenas nas plantas de N. benthamiana, enquanto o teste RT-PCR em todas as plantulas avaliadas. Os resultados do sequenciamento mostraram altos valores de identidade de nucleotídeos com as sequências do vírus no NCBI. A transmissão mecânica foi o método mais eficaz para a inoculação do CMV e as técnicas de análise molecular foram mais sensíveis e confiáveis ​​para identificação do CMV, em comparação com os testes serológicos

Comparative and functional genomics of the protozoan parasite Babesia divergens highlighting the invasion and egress processes

Babesiosis is considered an emerging disease because its incidence has significantly increased in the last 30 years, providing evidence of the expanding range of this rare but potentially life-threatening zoonotic disease. Babesia divergens is a causative agent of babesiosis in humans and cattle in Europe. The recently sequenced genome of B. divergens revealed over 3,741 protein coding-genes and the 10.7-Mb high-quality draft become the first reference tool to study the genome structure of B. divergens. Now, by exploiting this sequence data and using new computational tools and assembly strategies, we have significantly improved the quality of the B. divergens genome. The new assembly shows better continuity and has a higher correspondence to B. bovis chromosomes. Moreover, we present a differential expression analysis using RNA sequencing of the two different stages of the asexual lifecycle of B. divergens: the free merozoite capable of invading erythrocytes and the intraerythrocytic parasite stage that remains within the erythrocyte until egress. Comparison of mRNA levels of both stages identified 1,441 differentially expressed genes. From these, around half were upregulated and the other half downregulated in the intraerythrocytic stage. Orthogonal validation by real-time quantitative reverse transcription PCR confirmed the differential expression. A moderately increased expression level of genes, putatively involved in the invasion and egress processes, were revealed in the intraerythrocytic stage compared with the free merozoite. On the basis of these results and in the absence of molecular models of invasion and egress for B. divergens, we have proposed the identified genes as putative molecular players in the invasion and egress processes. Our results contribute to an understanding of key parasitic strategies and pathogenesis and could be a valuable genomic resource to exploit for the design of diagnostic methods, drugs and vaccines to improve the control of babesiosis.This work was funded by grants from Ministerio de Economía y Competitividad from Spain (AGL2010-21774 and AGL2014-56193 R to EM and LMG). ES was awarded a research fellowship from Plan Estatal de Investigación Científica y Técnica y de Innovación, Ministerio de Economía y Competitividad, Spain (http://www.mineco.gob.es/portal/site/mineco/). Work in CL’s laboratory is funded by a grant from the National Institutes of Health (https://www.nih.gov/) NIH- 1R01HL140625-01. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscriptS

Defective lysosomal proteolysis and axonal transport are early pathogenic events that worsen with age leading to increased APP metabolism and synaptic Abeta in transgenic APP/PS1 hippocampus

Background: Axonal pathology might constitute one of the earliest manifestations of Alzheimer disease. Axonal dystrophies were observed in Alzheimer’s patients and transgenic models at early ages. These axonal dystrophies could reflect the disruption of axonal transport and the accumulation of multiple vesicles at local points. It has been also proposed that dystrophies might interfere with normal intracellular proteolysis. In this work, we have investigated the progression of the hippocampal pathology and the possible implication in Abeta production in young (6 months) and aged (18 months) PS1(M146L)/APP(751sl) transgenic mice. Results: Our data demonstrated the existence of a progressive, age-dependent, formation of axonal dystrophies, mainly located in contact with congophilic Abeta deposition, which exhibited tau and neurofilament hyperphosphorylation. This progressive pathology was paralleled with decreased expression of the motor proteins kinesin and dynein. Furthermore, we also observed an early decrease in the activity of cathepsins B and D, progressing to a deep inhibition of these lysosomal proteases at late ages. This lysosomal impairment could be responsible for the accumulation of LC3-II and ubiquitinated proteins within axonal dystrophies. We have also investigated the repercussion of these deficiencies on the APP metabolism. Our data demonstrated the existence of an increase in the amyloidogenic pathway, which was reflected by the accumulation of hAPPfl, C99 fragment, intracellular Abeta in parallel with an increase in BACE and gamma-secretase activities. In vitro experiments, using APPswe transfected N2a cells, demonstrated that any imbalance on the proteolytic systems reproduced the in vivo alterations in APP metabolism. Finally, our data also demonstrated that Abeta peptides were preferentially accumulated in isolated synaptosomes. Conclusion: A progressive age-dependent cytoskeletal pathology along with a reduction of lysosomal and, in minor extent, proteasomal activity could be directly implicated in the progressive accumulation of APP derived fragments (and Abeta peptides) in parallel with the increase of BACE-1 and gamma-secretase activities. This retard in the APP metabolism seemed to be directly implicated in the synaptic Abeta accumulation and, in consequence, in the pathology progression between synaptically connected regions

Abnormal accumulation of autophagic vesicles correlates with axonal and synaptic pathology in young Alzheimer’s mice hippocampus

Dystrophic neurites associated with amyloid plaques precede neuronal death and manifest early in Alzheimer’s disease (AD). In this work we have characterized the plaque-associated neuritic pathology in the hippocampus of young (4- to 6-month-old) PS1M146L/ APP751SL mice model, as the initial degenerative process underlying functional disturbance prior to neuronal loss. Neuritic plaques accounted for almost all fibrillar deposits and an axonal origin of the dystrophies was demonstrated. The early induction of autophagy pathology was evidenced by increased protein levels of the autophagosome marker LC3 that was localized in the axonal dystrophies, and by electron microscopic identification of numerous autophagic vesicles filling and causing the axonal swellings. Early neuritic cytoskeletal defects determined by the presence of phosphorylated tau (AT8-positive) and actin–cofilin rods along with decreased levels of kinesin-1 and dynein motor proteins could be responsible for this extensive vesicle accumulation within dystrophic neurites. Although microsomal Ab oligomers were identified, the presence of A11-immunopositive Ab plaques also suggested a direct role of plaque-associated Ab oligomers in defective axonal transport and disease progression. Most importantly, presynaptic terminals morphologically disrupted by abnormal autophagic vesicle buildup were identified ultrastructurally and further supported by synaptosome isolation. Finally, these early abnormalities in axonal and presynaptic structures might represent the morphological substrate of hippocampal dysfunction preceding synaptic and neuronal loss and could significantly contribute to AD pathology in the preclinical stages.Fondo de Investigación Sanitaria (FIS). Instituto de Salud Carlos III, España. PS09/00099, PS09/00151, PS09/00848 y PS09/00376Junta de Andalucía. SAS P09/496 y CTS-479

Correlación clínico patológica de los fallecidos en el postoperatorio de revascularización miocárdica, período 2006 al 2009 del Hospital

Introducción: en Cuba, al igual que en el resto del mundo, las enfermedades isquémicas cardiacas ocupan las primeras causas de muerte con un incremento del número de cirugías de revascularización miocárdica. El amplio uso de autopsia en Cuba y su eficacia, motivó establecer la correlación clínico patológica de los pacientes fallecidos operados de revascularización miocárdica como herramienta de control de la calidad en el quehacer profesional. Objetivo: determinar la correlación clínico patológica de los fallecidos en el postoperatorio de revascularización miocárdica en cirugía cardiovascular del Hospital “Hermanos Ameijeiras” entre 2006 a 2009. Materiales y métodos: se realizó un estudio descriptivo, retrospectivo y de corte transversal, se analizaron causas básicas y directas de muerte, clínicamente y por autopsia; se compararon según parámetros de anatomía patológica para evaluar calidad del diagnóstico en coincidentes (total o parcial) o no coincidentes. Se obtuvieron 682 pacientes operados en este período; la muestra quedó constituida por 59 fallecidos para un 8,6% de mortalidad. Se contó con la aprobación del comité de ética. Resultados: más del 70% del total de fallecidos corresponde a mayores de 60 años. Se observó un incremento de fallecidos masculinos sobre femeninos con relación 7:2. Existe prevalencia en factores de riesgo como hipertensión arterial e infarto cardíaco previo. La primera causa directa de muerte tanto clínica como por autopsia fue el fallo multiorgánico seguido del choque cardiogénico. Según causas básicas de muerte la ateroesclerosis ocupó el primer lugar con 91,5% y 98,3% clínicamente y por autopsia respectivamente. No existió correlación clínico patológica en 20,3% de causas directas de muerte, y 8,5% en causas básicas de muerte. Conclusiones: los parámetros fueron adecuados para discrepancias diagnosticas en este estudio, con rango de aceptabilidad de 10 al 40%. Se diagnosticaron 20 infartos agudos del miocardio, solo siete pasaron desapercibidos. Las discrepancias para infarto agudo de miocardio, mundialmente oscilan entre 20 a 74%, en el estudio fue del 26%. Se diagnosticaron tres casos de tromboembolismo pulmonar y dos dejaron de diagnosticarse. Las discrepancias para tromboembolismo pulmonar, mundialmente oscilan del 50 a 89%, en este caso fue del 40%. (MÉD.UIS. 2011;24(3):239-45).Palabras clave: Revascularización Miocárdica. Correlación anatomopatológica. Mortalidad.Clinical and pathological correlationship of deceased patients in postoperative myocardial revascularization. From 2006 to 2009 at “Hermanos Ameijeiras” Hospital, Cuba.Introduction: In Cuba like the rest of the world, the first cause of death are heart isquemic diseases and there is an increasing number of myocardial revascularization. We use autopsy regularly and we could use the results to establish clinical and pathological correlationship of deceased patients in postoperative myocardial revascularization to improves our medical and professional work. Objective: to determine Clinical and pathological correlation of deceased patients in postoperative myocardial revascularization. “Hermanos Ameijeiras” Hospital (January2006 – december 2009). Materials and Methods: a descriptive, transversal and retrospective study was realized, in the retrospective period dating from January 2006 to December 2009, In the Cardiology Center of Surgery Clinic Hospital “Hermanos Ameijeiras.” This work was approved by the Ethics Committee responsible for this investigation. The sample was constituted by 59 deceased patients, in each one we analyze clinical and pathological direct and basic causes of death, then a comparison was made according with international rules and we express the results in final coincidence (total, partial or not). Results: the predominant age of deceased patients after myocardial revascularization surpassed 60 years of age over 70%. The coronary risk factors largely associated were hypertension and acute myocardial infarction. The majority of patients were male over female with a relationship of 7:2. The first direct cause of death clinical and by autopsy was multiorgan failure followed by cardiogenic shock. The first basic cause of death clinical and by autopsy was Atherosclerosis coincidently. We cannot found clinical and pathological coincidence in 20.3% in direct causes of death, and 8,5% in basic causes of death. Conclusions: in our study we are in the acceptability range of not coincident diagnostics, even in the range from 10 to 40%. 20 acute myocardial infarction were identify and 7 of them were not. Clinical and pathological international disagreement for acute myocardial infarction is from 20 to 74% and we are in 26%. Three pulmonary embolisms were identify and two of them were not. Clinical and pathological international Disagreement for pulmonary embolism is from 50 al 89% and we are in 40%. (MÉD.UIS. 2011;24(3):239-45).Key words: Myocardial revascularization. Clinical and pathological correlationship. Mortality

Conservación ex situ mediante el establecimiento de cultivo in vitro de semillas de Prosopis limensis “Huarango” de Ica, Perú

El “Huarango”, Prosopis limensis es una especie leñosa de la familia de las fabáceas que se encuentra ubicada en el bosque seco de Ica, de importancia clave en este ecosistema y considerada por diferentes causas en estado de peligro. El cultivo in vitro de semillas de esta especie se presenta como una estrategia adecuada de conservación, debido a las altas tasas de multiplicación que promueve, la economía en tiempo y costos de producción y por las posibilidades a futuro de mejoramiento y reforestación. El objetivo del presente estudio es el establecimiento de una metodología efectiva para la germinación óptima de semillas almacenadas de esta especie. Las semillas fueron obtenidas de 4 accesiones experimentales representativas procedentes del departamento de Ica, que se sometieron a un procedimiento de escarificación física, las semillas fueron sumergidas en agua temperada (70 °C) y reposándolas hasta alcanzar la temperatura de 37 °C. Posteriormente a los procesos de esterilización convencionales, las semillas fueron sembradas en medio básico M&S con vitaminas tiamina HCl (1,0 mg/l) y m-inositol (100 mg/l), sacarosa 2% y agar 0,6%, e incubados a 23 °C +/- 2 horas, por un fotoperiodo de 16 horas luz. De las accesiones evaluadas a los 24 días, la CPUC-117 presentó el mayor porcentaje de germinación, superior al 90%. Los resultados del presente trabajo constituyen el precedente necesario para iniciar los ensayos a mayor escala de micropropagación in vitro del “Huarango” con fines de conservación