oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 634 )

2018 ( 922 )

2017 ( 939 )

2016 ( 1262 )

Custom range...

Search Results: 1 - 10 of 560287 matches for " José M. Rodríguez F. "
All listed articles are free for downloading (OA Articles)
Page 1 /560287
Display every page Item
Rescue of Infectious Birnavirus from Recombinant Ribonucleoprotein Complexes
Romy M. Dalton, José F. Rodríguez
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0087790
Abstract: Birnaviruses are unconventional members of the icosahedral double-stranded (dsRNA) RNA virus group. The main differential birnavirus trait is the lack of the inner icosahedral transcriptional core, a ubiquitous structure conserved in all other icosahedral dsRNA viruses, that shelters the genome from cellular dsRNA sensors and provide the enzymatic machinery to produce and extrude mature messenger RNAs. In contrast, birnaviral particles enclose ribonucleoprotein (RNP) complexes formed by the genome segments, the dsRNA-binding VP3 polypeptide and the virus-encoded RNA polymerase (RdRp). The presence of RNPs suggests that the birnavirus replication program might exhibit significant differences with respect to those of prototypal dsRNA viruses. However, experimental evidences supporting this hypothesis are as yet scarce. Of particular relevance for the understanding of birnavirus replication is to determine whether RNPs act as intracellular capsid-independent transcriptional units. Our study was focused to answer this question using the infectious bursal disease virus (IBDV), the best characterized birnavirus, as model virus. Here, we describe the intracellular assembly of functional IBDV RNPs in the absence of the virus-encoded VP2 capsid polypeptide. Recombinant RNPs are generated upon coexpression of the IBDV VP1 and RdRp polypeptides and transfection of purified virus dsRNA. Presented data show that recombinant RNPs direct the expression of the IBDV polypeptide repertoire and the production of infectious virus in culture cells. Results described in this report constitute the first direct experimental evidence showing that birnaviral RNPs are intracellularly active in the absence of the virus capsid. This finding is consistent with presented data indicating that RNP formation precedes virus assembly in IBDV-infected cells, and supports the recently proposed IBDV replication model entailing the release of RNPs during the initial stages of the infection. Indeed, results presented here also support the previously proposed evolutionary connection between birnaviruses and positive-strand single-stranded RNA viruses.
The Infectious Bursal Disease Virus RNA-Binding VP3 Polypeptide Inhibits PKR-Mediated Apoptosis
Idoia Busnadiego, Ana M. Maestre, Dolores Rodríguez, José F. Rodríguez
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0046768
Abstract: Infectious bursal disease virus (IBDV) is an avian pathogen responsible for an acute immunosuppressive disease that causes major losses to the poultry industry. Despite having a bipartite dsRNA genome, IBDV, as well as other members of the Birnaviridae family, possesses a single capsid layer formed by trimers of the VP2 capsid protein. The capsid encloses a ribonucleoprotein complex formed by the genome associated to the RNA-dependent RNA polymerase and the RNA-binding polypeptide VP3. A previous report evidenced that expression of the mature VP2 IBDV capsid polypeptide triggers a swift programmed cell death response in a wide variety of cell lines. The mechanism(s) underlying this effect remained unknown. Here, we show that VP2 expression in HeLa cells activates the double-stranded RNA (dsRNA)-dependent protein kinase (PKR), which in turn triggers the phosphorylation of the eukaryotic initiation factor 2α (eIF2α). This results in a strong blockade of protein synthesis and the activation of an apoptotic response which is efficiently blocked by coexpression of a dominant negative PKR polypeptide. Our results demonstrate that coexpression of the VP3 polypeptide precludes phosphorylation of both PKR and eIF2α and the onset of programmed cell death induced by VP2 expression. A mutation blocking the capacity of VP3 to bind dsRNA also abolishes its capacity to prevent PKR activation and apoptosis. Further experiments showed that VP3 functionally replaces the host-range vaccinia virus (VACV) E3 protein, thus allowing the E3 deficient VACV deletion mutant WRΔE3L to grow in non-permissive cell lines. According to results presented here, VP3 can be categorized along with other well characterized proteins such us VACV E3, avian reovirus sigmaA, and influenza virus NS1 as a virus-encoded dsRNA-binding polypeptide with antiapoptotic properties. Our results suggest that VP3 plays a central role in ensuring the viability of the IBDV replication cycle by preventing programmed cell death.
Grado de competencia, presión de la deuda y productividad empresarial: un análisis empírico desde la perspectiva del gobierno corporativo
Juan A. Maroto A.,Mónica Melle H.,Ignacio Moreno G.,José M. Rodríguez F.
Panorama Socioeconómico , 2006,
Abstract: Este trabajo ofrece evidencia emp rica acerca del impacto sobre la productividad empresarial derivado del grado de competencia, el poder de mercado, la presi n financiera del endeudamiento y la estructura de la propiedad de la empresa. En el an lisis, se estiman varios modelos din micos de regresi n mediante el m todo generalizado de momentos propuesto por Arellano y Bond (1991), a partir de una muestra de datos de panel constituida por 4.947 empresas manufactureras espa olas pertenecientes a 19 sectores industriales diferentes, durante un periodo que abarca del a o 1994 al a o 2003. Vistos en su conjunto, los resultados alcanzados sugieren que la competencia, junto con la presi n financiera y el tipo de accionista de control en cada empresa, influyen sobre la productividad empresarial, detect ndose alguna evidencia de que pueden actuar a veces como mecanismos complementarios de los c digos de buen gobierno corporativo y de los habituales sistemas de disciplina aplicados por los mercados financieros.
PRONóSTICO NEONATAL DEL RECIéN NACIDO DE MUY BAJO PESO: HOSPITAL REGIONAL DE PUERTO MONTT, 2000-2005
Caro M,José; Flores H,Gerardo; Ortiz F,Erika; Anwandter Sen,Carlos; Rodríguez A,Daniel;
Revista chilena de obstetricia y ginecología , 2007, DOI: 10.4067/S0717-75262007000500002
Abstract: objective: to describe obstetric morbidity, perinatal management and neonatal outcome in very low birth weight new born (vlbwnb). method: cross-sectional study in the puerto montt hospital in 347 vlbwnb, from 2000 to 2005. results: the vlbwnb incidence was 1.59%. 70% of the patients received prenatal corticoids. the main cause of interruption was hypertensive disorders; 68.5% of births were by caesarean delivery; severe neonatal depression occurred in 23.7% and 9.3% by apgar score at one and five minutes respectively. the caesarean delivery odds ratio for severe neonatal depression and neonatal death was 0.41 (ic 95%=0.25-0.70) and 0.43 (ic 95%=0.26-0.70), respectively. the main neonatal complications were respiratory distress syndrome (61.5%) and neonatal sepsis (24.7%), 29.7% of the new born died. the main mortality causes were prematurity (44.7%), infections (30.1%) and malformations (14.6%). conclusions: at the evaluated period, the management of vlbwnb at our hospital presents a significant increment in antenatal corticoids administration, surfactant and nasal cpap use. also presents a significant reduction of severe neonatal depression at five minutes in apgar score. the neonatal survival shows a significant increment in 500 to 749 g of birth weight cuartil. caesarean section was associated with significant diminution of severe neonatal depression and neonatal death in vlbwnb
Neurocitoma o tumor epitelial disembrioplásico Neurocytoma or dysembryoplasia epithelial tumor
Ceferina F. Rodríguez Vilorio,José Alert Silva,álvaro Suárez Arias,Lisbeth Cordero Méndez
Revista Cubana de Medicina , 2010,
Abstract: El neurocitoma o tumor epitelial disembrioplásico (TND) es un tumor infrecuente del sistema nervioso central (SNC) clasificado Grado I, según la OMS, y las series que aparecen en la literatura médica informan de pocos casos. Por considerarse una entidad poco frecuente y por haber asistido en un corto período a 2 pacientes adolescentes uno con recidiva de tumor cerebral que fue reintervenido y donde el diagnóstico patológico inicial se correspondía con un astrocitoma de bajo grado y la otra, llevada a sala de operaciones con el diagnóstico de astrocitoma de alto grado, y donde después de estudios de inmunohistoquímica el diagnóstico final fue de tumor neuroepitelial disembrioplásico extraventricular. Se indicó tratamiento con radiaciones ionizantes. Se decidió revisar la literatura y presentar estos 2 casos. The Neurocytoma or dysembryoplasia epithelial tumor (DET) is an infrequent tumor of the central nervous system (CNS) classified as Degree I according to the WHO and the series appearing in the medical literature report not much cases. It is considered a not much frequent entity and due to the care during a short period to 2 adolescent patients, one of them with relapse of cerebral tumor re-operated on and where the former pathologic diagnosis was in correspondence with a high degree astrocytoma and that after the immunohistochemistry studies the final diagnosis was of a extraventricular dysembryoplasia neuroepithelial tumor. The treatment prescribed was with ionizing radiations. Literature was reviewed and two cases were presented.
Pesticide Removal from Aqueous Solutions by Adding Salting Out Agents
Fátima Moscoso,Francisco J. Deive,José M. S. S. Esperan?a,Ana Rodríguez
International Journal of Molecular Sciences , 2013, DOI: 10.3390/ijms141020954
Abstract: Phase segregation in aqueous biphasic systems (ABS) composed of four hydrophilic ionic liquids (ILs): 1-butyl-3-methylimidazolium methylsulfate and 1-ethyl-3-methylimidazolium methylsulfate (C nC 1im C 1SO 4, n = 2 and 4), tributylmethyl phosphonium methylsulfate (P 4441 C 1SO 4) and methylpyridinium methylsulfate (C 1Py C 1SO 4) and two high charge density potassium inorganic salts (K 2CO 3 and K 2HPO 4) were determined by the cloud point method at 298.15 K. The influence of the addition of the selected inorganic salts to aqueous mixtures of ILs was discussed in the light of the Hofmeister series and in terms of molar Gibbs free energy of hydration. The effect of the alkyl chain length of the cation on the methylsulfate-based ILs has been investigated. All the solubility data were satisfactorily correlated to several empirical equations. A pesticide (pentachlorophenol, PCP) extraction process based on the inorganic salt providing a greater salting out effect was tackled. The viability of the proposed process was analyzed in terms of partition coefficients and extraction efficiencies.
Eficiencia técnica de los centros avanzados de atención primaria de la salud de Tabasco (CAAPS). Aplicación del método de optimización análisis envolvente de datos (DEA)
José F. García-Rodríguez,Gustavo A. Rodríguez-León,M.C. Anaí García-Fari?a
Salud en Tabasco , 2008,
Abstract: Objetivo. Determinar la eficiencia técnica asociada a la operación de los Centros Avanzados de Atención Primaria de la Salud de Tabasco (CAAPS), mediante la aplicación de la metodología de análisis envolvente de datos, con el propósito de identificar las unidades de mejor práctica productiva; fomentar la sana competencia; impulsar la eficiencia productiva mediante la incorporación de procesos gerenciales de benchmarking, y elevar la calidad de los servicios de salud ofrecidos a la población tabasque a. Material y métodos. Se desarrolló un estudio descriptivo, transversal para la determinación de la eficiencia técnica en el a o 2006 en la operación de las 37 unidades médicas de la Secretaría de Salud de Tabasco conocidas como CAAPS. En el análisis, las variables consideradas como insumos productivos (inputs) fueron: a) médicos en servicio, b) enfermeras en servicio, c) consultorios de medicina general o familiar, d) camas disponibles, y e) núcleos básicos existentes. Como productos obtenidos (outputs) se consideraron los siguientes servicios de salud: a) consultas externas, b) consultas reproductivas, c) vacunas aplicadas, d) detecciones de enfermos crónicos, e) enfermos crónicos en control, f) acciones de salud bucal, y g) actividades de promoción. En el análisis se aplicó el método de Optimización Análisis Envolvente de Datos (DEA), para lo cual se utilizó el software "Frontier Analyst" versión 3 Professional. El modelo se corrió utilizando los procedimiento de rendimientos variables a escala y de maximización de resultados productivos. Resultados. únicamente 17 de las unidades estudiadas resultaron ser eficientes al 100% en su operación en términos de productividad médica. Al resultar ineficientes las 20 unidades restantes, existe un amplio margen de mejora potencial en la eficiencia productiva del sistema en su conjunto. Conclusión. Se identificaron las unidades médicas técnicamente eficientes, así como aquellas que funcionan con diversos grados de ineficiencia, y que son susceptibles de mejora mediante el establecimiento de procesos gerenciales de benchmarking, con lo cual se podría impulsar la eficiencia técnica y la calidad en la prestación de servicios en el primer nivel de atención de la salud en Tabasco.
Investigating Particle Acceleration in Protostellar Jets: The Triple Radio Continuum Source in Serpens
Adriana Rodríguez-Kamenetzky,Carlos Carrasco-González,Anabella Araudo,José M. Torrelles,Guillem Anglada,Josep Martí,Luis F. Rodríguez,Carlos Valotto
Physics , 2015,
Abstract: While most protostellar jets present free-free emission at radio wavelengths, synchrotron emission has been also proposed to be present in a handful of these objects. The presence of non-thermal emission has been inferred by negative spectral indices at centimeter wavelengths. In one case (the HH 80-81 jet arising from a massive protostar), its synchrotron nature was confirmed by the detection of linearly polarized radio emission. One of the main consequences of these results is that synchrotron emission implies the presence of relativistic particles among the non-relativistic material of these jets. Therefore, an acceleration mechanism should be taking place. The most probable scenario is that particles are accelerated when the jets strongly impact against the dense envelope surrounding the protostar. Here, we present an analysis of radio observations obtained with the Very Large Array of the Triple Radio Source in the Serpens star-forming region. This object is known to be a radio jet arising from an intermediate-mass protostar. It is also one of the first protostellar jets where the presence of non-thermal emission was proposed. We analysed the dynamics of the jet as well as the nature of the emission and discuss these issues in the context of the physical parameters of the jet and the particle acceleration phenomenon.
Arnold Tongues for Discrete Hill’s Equation  [PDF]
José Guillermo Rodríguez Servín, M. Joaquin Collado
Applied Mathematics (AM) , 2017, DOI: 10.4236/am.2017.812133
Abstract:
In this work we study two types of Discrete Hill’s equation. The first comes from the discretization process of a Continuous-time Hill’s equation, we called Discretized Hill’s equation. The Second is a naturally obtained in Discrete-Time and will be called Discrete-time Hill’s equation. The objective of discretization is preserving the continuous-time behavior and we show this property. On the contrary a completely different dynamic property was found for the Discrete-Time Hill’s equation. At the end of the paper is shown that both types share the nonoscillatory behavior of solutions in the 0-th Arnold Tongue.
Electronic and structural characterization of divacancies in irradiated graphene
Miguel M. Ugeda,Iván Brihuega,Fanny Hiebel,Pierre Mallet,Jean-Yves Veuillen,José M. Gómez-Rodríguez,Félix Ynduráin
Physics , 2011, DOI: 10.1103/PhysRevB.85.121402
Abstract: We provide a thorough study of a carbon divacancy, a fundamental but almost unexplored point defect in graphene. Low temperature scanning tunneling microscopy (STM) imaging of irradiated graphene on different substrates enabled us to identify a common two-fold symmetry point defect. Our first principles calculations reveal that the structure of this type of defect accommodates two adjacent missing atoms in a rearranged atomic network formed by two pentagons and one octagon, with no dangling bonds. Scanning tunneling spectroscopy (STS) measurements on divacancies generated in nearly ideal graphene show an electronic spectrum dominated by an empty-states resonance, which is ascribed to a spin-degenerated nearly flat band of $\pi$-electron nature. While the calculated electronic structure rules out the formation of a magnetic moment around the divacancy, the generation of an electronic resonance near the Fermi level, reveals divacancies as key point defects for tuning electron transport properties in graphene systems.
Page 1 /560287
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.