38 research outputs found

    Critical Analysis of Hypothesis Tests in Federal Information Processing Standard (140-2)

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    This work presents an analysis of the existing dependencies between the tests of the FIPS 140-2 battery. Two main analytical approaches are utilized, the first being a study of correlations through the Pearson’s correlation coefficient that detects linear dependencies, and the second one being a novel application of the mutual information measure that allows detecting possible non-linear relationships. In order to carry out this study, the FIPS 140-2 battery is reimplemented to allow the user to obtain p-values and statistics that are essential for more rigorous end-user analysis of random number generators (RNG)

    Estudio de las propiedades fisicoquímicas y texturales de polímeros acetilénicos y diacetilénicos como cadenas principales y grupos cromóforos en cadenas laterales

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    Se sintetizaron dos polímeros diacetilénicos que contienen grupos polares diacetilénicos y tolanos como cromóforos a través de la técnica de acoplamiento oxidativo. También se realizó un electrohilado de uno de los polímeros para poder observar y hacer un análisis textural comparativo. A partir de la isoterma de adsorción de nitrógeno a 77 K se obtuvo el área superficial específica para el polímero 2,5. La isoterma del material refleja las características de sólidos con baja porosidad, lo cual se corrobora con los estudios de microcopía de barrido. Con la finalidad de explorar su afinidad con el dióxido de carbono (CO₂), se obtuvieron las isotermas de adsorción de CO₂ a la temperatura de 298 K, para ambos polímeros.Two diacetylene polymers containing diacetylene polar groups and tolan as chromophores were synthesized through the oxidative coupling technique. An electro-spinning of the polymer was also performed to observe and make a comparative textural analysis. The specific surface area for polymer 2.5 was obtained from the nitrogen adsorption isotherm at 77 K. The isotherm of the material reflects the characteristics of solids with low porosity, which is corroborated by scanning microcopy studies. In order to explore their affinity with carbon dioxide (CO₂), the CO₂ adsorption isotherms at a temperature of 298 K were obtained for both polymers

    An Emerging Infectious Disease Triggering Large-Scale Hyperpredation

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    Hyperpredation refers to an enhanced predation pressure on a secondary prey due to either an increase in the abundance of a predator population or a sudden drop in the abundance of the main prey. This scarcely documented mechanism has been previously studied in scenarios in which the introduction of a feral prey caused overexploitation of native prey. Here we provide evidence of a previously unreported link between Emergent Infectious Diseases (EIDs) and hyperpredation on a predator-prey community. We show how a viral outbreak caused the population collapse of a host prey at a large spatial scale, which subsequently promoted higher-than-normal predation intensity on a second prey from shared predators. Thus, the disease left a population dynamic fingerprint both in the primary host prey, through direct mortality from the disease, and indirectly in the secondary prey, through hyperpredation. This resulted in synchronized prey population dynamics at a large spatio-temporal scale. We therefore provide evidence for a novel mechanism by which EIDs can disrupt a predator-prey interaction from the individual behavior to the population dynamics. This mechanism can pose a further threat to biodiversity through the human-aided disruption of ecological interactions at large spatial and temporal scales.MM and JASZ were partially supported by a project of the Spanish Ministerio de Educación y Ciencia (reference CGL-2006-10689/BOS)

    Pregnancy Control in Patients with Systemic Lupus Erythematosus and Antiphospholipid Syndrome. Part 1: Infertility, Ovarian Preservation and Preconception Assessment. Consensus Document of the Spanish Society of Gynaecology and Obstetrics (SEGO), the Spanish Society of Internal Medicine (SEMI) and the Spanish Society of Rheumatology (SER)

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    Objetivo: El embarazo y el puerperio se consideran una situación de riesgo en mujeres con lupus eritematoso sistémico (LES) y síndrome antifosfolípido (SAF). Es esencial que especialistas en enfermedades autoinmunes y en embarazo de alto riesgo intervengan en su seguimiento de forma coordinada. La Sociedad Española de Ginecología y Obstetricia, la Sociedad Española de Medicina Interna, y la Sociedad Española de Reumatología han constituido un grupo de trabajo paritario para la elaboración de 3 documentos de consenso. Métodos: Las fases del trabajo fueron: distribución del trabajo en grupos correspondientes a los 3 períodos relacionados con la gestación, identificación de áreas clave, revisión de la literatura y formulación de recomendaciones. Resultados: En este primer documento se incluyen las primeras 48 recomendaciones que tratan aspectos relacionados con la infertilidad, la necesidad y los tratamientos de preservación gonadal y la valoración preconcepcional. Conclusiones: Estas recomendaciones multidisciplinares se consideran herramientas en la toma de decisiones para los clínicos involucrados en la asistencia a pacientes con LES/SAF durante el embarazo

    Applied diagnostics in liver cancer. Efficient combinations of sorafenib with targeted inhibitors blocking AKT/mTOR

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    Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths worldwide. There is increasing interest in developing specific markers to serve as predictors of response to sorafenib and to guide targeted therapy. Using a sequencing platform designed to study somatic mutations in a selection of 112 genes (HepatoExome), we aimed to characterize lesions from HCC patients and cell lines, and to use the data to study the biological and mechanistic effects of case-specific targeted therapies used alone or in combination with sorafenib. We characterized 331 HCC cases in silico and 32 paired samples obtained prospectively from primary tumors of HCC patients. Each case was analyzed in a time compatible with the requirements of the clinic (within 15 days). In 53% of the discovery cohort cases, we detected unique mutational signatures, with up to 34% of them carrying mutated genes with the potential to guide therapy. In a panel of HCC cell lines, each characterized by a specific mutational signature, sorafenib elicited heterogeneous mechanistic and biological responses, whereas targeted therapy provoked the robust inhibition of cell proliferation and DNA synthesis along with the blockage of AKT/mTOR signaling. The combination of sorafenib with targeted therapies exhibited synergistic anti-HCC biological activity concomitantly with highly effective inhibition of MAPK and AKT/mTOR signaling. Thus, somatic mutations may lead to identify case-specific mechanisms of disease in HCC lesions arising from multiple etiologies. Moreover, targeted therapies guided by molecular characterization, used alone or in combination with sorafenib, can effectively block important HCC disease mechanisms.FUNDING: Grants from ISCIII, co-financed by the European Union (FEDER) (PI16/00156), Ramón and Cajal research program from MINECO (RYC-2013-14097) and FUNDACIÓN LUCHAMOS POR LA VIDA to JPV. Grants from ISCIII (RD06/0020/0107-RD012/0036/0060) to MAP. Grant from ISCIII (Ref. PIE15/00079) to JC & JPV. NGD is a recipient of a UC-IDIVAL pre-doctoral fellow. I.V. was also supported by the Ramón and Cajal research program

    Combined impact of healthy lifestyle factors on risk of asthma, rhinoconjunctivitis and eczema in school children: ISAAC phase III

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    Background Asthma is not the key focus of prevention strategies. A Healthy Lifestyle Index (HLI) was developed to examine the combined effect of modifiable lifestyle factors on asthma, rhinoconjunctivitis and eczema using data from the International Study of Asthma and Allergies in Childhood (ISAAC) phase III. Methods Information on symptoms of asthma, rhinoconjunctivitis, eczema and several lifestyle factors was obtained from children aged 6-7 years through written questionnaires. The HLI combined five lifestyle factors: no parental smoking, child's adherence to Mediterranean diet, child's healthy body mass index, high physical activity and non-sedentary behaviour. The association between the HLI and risk of asthma, rhinoconjunctivitis and eczema was evaluated using multilevel mixed-effects logistic regression models. Findings Data of 70 795 children from 37 centres in 19 countries were analysed. Each additional healthy lifestyle factor was associated with a reduced risk of current wheeze (OR 0.87, 95% CI 0.84 to 0.89), asthma ever (OR 0.89, 95% CI 0.87 to 0.92), current symptoms of rhinoconjunctivitis (OR 0.95, 95% CI 0.92 to 0.97) and current symptoms of eczema (OR 0.92, 95% CI 0.92 to 0.98). Theoretically, if associations were causal, a combination of four or five healthy lifestyle factors would result into a reduction up to 16% of asthma cases (ranging from 2.7% to 26.3 % according to region of the world). Conclusions These findings should be interpreted with caution given the limitations to infer causality from cross-sectional observational data. Efficacy of interventions to improve multiple modifiable lifestyle factors to reduce the burden asthma and allergy in childhood should be assessed

    Carotid body chemosensory responses in mice deficient of TASK channels

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    Background K+ channels of the TASK family are believed to participate in sensory transduction by chemoreceptor (glomus) cells of the carotid body (CB). However, studies on the systemic CB-mediated ventilatory response to hypoxia and hypercapnia in TASK1- and/or TASK3-deficient mice have yielded conflicting results. We have characterized the glomus cell phenotype of TASK-null mice and studied the responses of individual cells to hypoxia and other chemical stimuli. CB morphology and glomus cell size were normal in wild-type as well as in TASK1−/− or double TASK1/3−/− mice. Patch-clamped TASK1/3-null glomus cells had significantly higher membrane resistance and less hyperpolarized resting potential than their wild-type counterpart. These electrical parameters were practically normal in TASK1−/− cells. Sensitivity of background currents to changes of extracellular pH was drastically diminished in TASK1/3-null cells. In contrast with these observations, responsiveness to hypoxia or hypercapnia of either TASK1−/− or double TASK1/3−/− cells, as estimated by the amperometric measurement of catecholamine release, was apparently normal. TASK1/3 knockout cells showed an enhanced secretory rate in basal (normoxic) conditions compatible with their increased excitability. Responsiveness to hypoxia of TASK1/3-null cells was maintained after pharmacological blockade of maxi-K+ channels. These data in the TASK-null mouse model indicate that TASK3 channels contribute to the background K+ current in glomus cells and to their sensitivity to external pH. They also suggest that, although TASK1 channels might be dispensable for O2/CO2 sensing in mouse CB cells, TASK3 channels (or TASK1/3 heteromers) could mediate hypoxic depolarization of normal glomus cells. The ability of TASK1/3−/− glomus cells to maintain a powerful response to hypoxia even after blockade of maxi-K+ channels, suggests the existence of multiple sensor and/or effector mechanisms, which could confer upon the cells a high adaptability to maintain their chemosensory function

    Participación de hemoproteínas en la función uimiosensora de células neurosecretoras

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    En los mamíferos existe un sistema homeostático de tejidos con células sensibles a las variaciones en los niveles sanguíneos de O2 que permite generar de manera inmediata los ajustes respiratorios y cardiovasculares adecuados para la supervivencia del organismo ante el ambiente cambiante. Esta respuesta hiperventilatoria y de activación simpática a la hipoxia se inicia en los cuerpos carotídeos (CCs), cuyas células sensoras, ricas en neurotransmisores de tipo catecolaminérgico, hacen sinapsis con fibras nerviosas aferentes y generan potenciales de acción debido a la activación de canales iónicos dependientes de potencial. Sin embargo, pese a que la cascada de transducción del estímulo hipóxico en el CC es un modelo muy establecido, aún se desconoce la mólecula, o el conjunto de las mismas, causantes de esta detección, así como el mecanismo inicial de la respuesta adaptativa. Se han postulado varias hipótesis, que se engloban en dos modelos fundamentales: por un lado, se cree que el O2 podría interaccionar directamente con un canal de K+; el segundo modelo plantea una modulación indirecta de este canal por parte de hemoproteínas u otro tipo de moléculas sensoras

    α-Haemoglobin regulates sympathoadrenal cell metabolism to maintain a catecholaminergic phenotype

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    23 páginas, 7 figuras, 2 tablas.Discovery of haemoglobin A expression outside of the erythroid cell lineage suggests that oxygen transport is the main, but not the unique, function of adult haemoglobin chains in mammals. The contribution of haemoglobin A to antioxidant defences has been proposed in the territories where it is expressed. Catecholaminergic cells rely on an active oxidative metabolism to accomplish their biological function, but are exposed to strong oxidative stress due to metabolism of catecholaminergic transmitters. We show in the present study that peripheral catecholaminegic cells express the α- and not the β-haemoglobin A chains, and that α-haemoglobin expression could modulate the antioxidant capabilities of these cells. We also show that α-haemoglobin overexpression in PC12 cells leads to a selective increase of tyrosine hydroxylase synthesis and activity. This is achieved by means of a reorganization of antioxidant defences, decreasing cytoplasmic glutathione peroxidase and superoxide dismutase, and increasing mitochondrial peroxidase. Moreover, α-haemoglobin induces a decrease in lipogenesis and increase in lipid degradation, situations that help save NAD(P)H and favour supply of acetyl-CoA to the tricarboxylic acid cycle and production of reducing equivalents in the cell. All of these results point to a role for α-haemoglobin as a regulator of catecholaminergic cell metabolism required for phenotype acquisition and maintenance.The TH-EGFP mice were obtained from the Gene Expression Nervous System Atlas (GENSAT) Project [NINDS contracts N01NS02331 and HHSN271200723701C to The Rockefeller University (New York, NY, U.S.A.)]. The work was funded by the Marcelino Botín Foundation, the Spanish Ministry of Science and Education, and the Andalusian Government. CIBERNED is funded by the Instituto de Salud Carlos III. Support from the Spanish Ministry of Science and Education for M.T.M.A. (“FPI” predoctoral fellowship) is also acknowledged.Peer reviewe
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