317 research outputs found

    The organic air pollutant cumene hydroperoxide interferes with NOantioxidant role in rehydrating lichen

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    Organic pollutants effects on lichens have not been addressed. Rehydration is critical for lichens, a burst of free radicals involving NO occurs. Repeated dehydrations with organic pollutants could increase oxidative damage. Our aim is to learn the effects of cumene hydroperoxide (CP) during lichen rehydration using Ramalina farinacea (L.) Ach., its photobiont Trebouxia spp. and Asterochloris erici. Confocal imaging shows intracellular ROS and NO production within myco and phycobionts, being the chloroplast the main source of free radicals. CP increases ROS, NO and lipid peroxidation and reduces chlorophyll autofluorescence, although photosynthesis remains unaffected. Concomitant NO inhibition provokes a generalized increase of ROS and a decrease in photosynthesis. Our results suggest that CP induces a ompensatory hormetic response in Ramalina farinacea that could reduce the lichen s antioxidant resources after repeated desiccation-rehydration cycles. NO is important in the protection from CP.This project was funded by the Spanish Ministry of Education and Science [project numbers CGL2012-40058-C02-01 and CGL2009-13429-C02-01], project Prometeo 2008/174 of the Generalitat Valenciana and the project AECID PCI/A/024755/09 of the Spanish Ministry of Foreign Affaires.Catalá, M.; Gasulla Vidal, F.; Pradas Del Real, A.; García Breijo, FJ.; Reig Armiñana, J.; Barreno Rodriguez, E. (2013). The organic air pollutant cumene hydroperoxide interferes with NOantioxidant role in rehydrating lichen. Environmental Pollution. 179:277-284. https://doi.org/10.1016/j.envpol.2013.04.015S27728417

    Electromagnetic Neutrino Properties and Neutrino Oscillations in Electromagnetic Fields

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    The presence of medium and external magnetic field change electromagnetic properties of neutrino. In this article the behavior of neutrino magnetic moment in electromagnetic field is considered. On the basis the Bargmann-Michel-Telegdi equation for the case of models with CP invariance and P nonconservation the new type of neutrino resonances νLνR\nu_L \leftrightarrow \nu_R in the electromagnetic field is predicted.Comment: 6 page

    In vitro antiatherogenicity of extracts from Halimeda incrassata seaweed: antioxidant activity and smooth muscle cell migration studies

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    Aim: The aim of this work was to evaluate the in vitro atheroprotective potential of the seaweed Halimeda incrassata in smooth muscle cell migration and lipoprotein oxidation in relation to its antioxidant activity. Material and methods: Antioxidant activity was determinate by DPPH• radical scavenging assay and ORAC method. The inhibitory effect of the aqueous extract on LDL oxidation mediated by Cu2+ ions was determinate by TBARS and conjugated diene quantification. The effect of the seaweed aqueous extract on smooth muscle cell migration was evaluated in MOVAS-1 mouse aortic smooth muscle cell. Results: The inhibitory effect of the aqueous extract on lipoprotein oxidation mediated by Cu2+ was demonstrated. Seaweed extract caused dose-dependent inhibition of TBARS (IC50 = 0.8 mg/mL) and conjugated dienes formation. The seaweed had a high antioxidant activity in the assays performed. The activity could be related to the phenolic content of Halimeda incrassata. Conclusions: In summary, the results of this study represent a further step in the characterization of the atheroprotective action of Halimeda incrassata and indicate the seaweed could be used for a nutraceutical and/or phytoterapeutic application.Objetivos: El objetivo de este trabajo fue evaluar el potencial ateroprotector in vitro del alga Halimeda incrassata en la migración de células de músculo liso de ratón y la oxidación de lipoproteínas en relación con su actividad antioxidante. Material y métodos: La actividad antioxidante fue determinada mediante los métodos de inhibición de radicales DPPH y la Capacidad antioxidante total (ORAC). La actividad inhibitoria de la oxidación de LDL mediada por iones Cu2+ se determinó por la cuantificación de TBARS y dienos conjugados. El efecto del extracto acuoso sobre la migración de las células de músculo liso se evaluó en la línea de células de músculo liso aórtica de ratón MOVAS-1. Resultados: Se demostró el efecto inhibidor del extracto sobre la oxidación de LDL mediada por Cu2+. El extracto del alga causa inhibición dosis-dependiente de la formación de TBARS (IC50 = 0,8 mg/mL) y dienos conjugados. Las algas tuvieron una alta actividad antioxidante en los ensayos realizados y podría estar relacionada con el contenido de compuestos fenólicos. Conclusiones: Los resultados de este trabajo representan un paso más en la caracterización de la acción ateroprotectora de Halimeda incrassata y evidencian sus posibles aplicaciones como nutracéutico y/o fitofármaco.The research was funded by IFS grant F/4897-1. Partial funding was also provided by CIHR grant MOP24447, the Canadian Research Chair award (D.B.) and a personal grant from GSEP, offered by the Canadian Bureau for International Education (A.C) and CNPq- (Brasil)

    Are long gamma-ray bursts biased tracers of star formation? Clues from the host galaxies of the Swift/BAT6 complete sample of bright LGRBs. :III. Stellar masses, star formation rates, and metallicities at z > 1

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    (Abridged) Long gamma-ray bursts (LGRB) have been suggested as promising tracers of star formation owing to their association with the core-collapse of massive stars. The goal of this work is to characterise the population of host galaxies of LGRBs at 1 < z < 2, investigate the conditions in which LGRBs form at these redshifts and assess their use as tracers of star formation. We perform a spectro-photometric analysis to determine the stellar mass, star formation rate, specific star formation rate and metallicity of the complete, unbiased host galaxy sample of the Swift/BAT6 LGRB sample at 1 < z < 2. We compare the distribution of these properties to the ones of typical star-forming galaxies from the MOSDEF and COSMOS2015 Ultra Deep surveys, within the same redshift range. We find that, similarly to z < 1, LGRBs do not directly trace star formation at 1 < z < 2, and they tend to avoid high-mass, high-metallicity host galaxies. We also find evidence for an enhanced fraction of starbursts among the LGRB host sample with respect to the star-forming population of galaxies. Nonetheless we demonstrate that the driving factor ruling the LGRB efficiency is metallicity. The LGRB host distributions can be reconciled with the ones expected from galaxy surveys by imposing a metallicity upper limit of 12+logOH ~ 8.55. Metallicity rules the LGRB production efficiency, which is stifled at Z > 0.7 Zsun. Under this hypothesis we can expect LGRBs to trace star formation at z > 3, once the bulk of the star forming galaxy population are characterised by metallicities below this limit. The moderately high metallicity threshold found is in agreement with the conditions necessary to rapidly produce a fast-rotating Wolf-Rayet star a in close binary system, and could be accommodated by single star models under chemically homogeneous mixing with very rapid rotation and weak magnetic coupling.Comment: 19 pages, 17 figures, accepted for publication in Astronomy & Astrophysic

    Evaluaciones toxicológicas de un extracto acuoso del alga marina Bryothamnion triquetrum (Gmelin) M.A.Howe en estudios in vitro y modelos animales

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    Objetivo: El objetivo de este trabajo fue evaluar la toxicidad de un extracto acuoso del alga marina Bryothamnion triquetrum. Métodos: El ensayo de Ames se desarrolló con las cepas de S. typhimurium TA 1535, TA 1537 y TA 1538 con y sin activación metabólica. El estudio de citotoxicidad se realizó con células intestinales Caco-2 durante 24 y 48 horas de exposición al extracto y la viabilidad fue evaluada con la técnica de yoduro de propidio. El Estudio de Toxicidad Aguda se realizó con ratones Balc/c machos por vía oral e intraperitoneal y el Ensayo de Toxicidad por Dosis Repetidas se desarrolló con ratas Wistar de ambos sexos, durante 3 meses por vía oral con dosis de 8 y 32 mg/kg. Resultados: En el estudio de citotoxicidad con células Caco-2 se obtuvieron CL50 de 9,3 y 4,5 mg/mL con exposiciones de 24 y 48 horas respectivamente. El ensayo de Ames evidencia que no es mutágeno directo ni promutágeno hasta 1000 μg. La DL50 del extracto por vía intraperitoneal fue de 1205 mg/kg y por vía oral no se observó mortalidad en dosis de 2000 mg/kg. En el estudio de Toxicidad por Dosis Repetidas no se observó toxicidad. Conclusiones: A partir de estos resultados se puede postular que el extracto acuoso del alga marina B. triquetrum es inocuo, consideración necesaria, entre otras, para su posible uso como nutracéutico y/o fitofármaco.Aim: The aim of this work was to evaluate the toxicity of an aqueous extract from seaweed Bryothamnion triquetrum. Materials and Methods: Ames assay was developed with S. typhimurium TA 1535, TA 1537 and TA 1538 with and without metabolic activation. Citotoxicity study was carried out with intestinal cells Caco-2 during 24 and 48 hours of exhibition to the extract and the viability was evaluated with the technique of Propidium iodide. Acute Toxicity was carried out with mice Balc/c males for via oral and intraperitoneal and the Toxicity for Repeated Dose was developed with rats Wistar of both sexes, during 3 months for via oral with dose of 8 and 32 mg/kg. Results: Results of Ames assays showed that this extract is not direct mutagen or promutagen in quantity until 1000 μg. The cytotoxic effect (LC50) of Caco-2 cells after 24 and 48 h of exposition were 9,3 and 4,5 mg/mL respectively. The LD50 of the extract, with intraperitoneal administration was 1205 mg/kg and by oral via not produce mortality in doses until 2000 mg/kg. At the doses of 8 and 32 mg/kg of extract, the repeated oral administration produced no toxic effects. Conclusions: In summary, this paper adds convincing evidences in support of innocuous of the aqueous extract of B.triquetrum. Altogether; these results represent another step towards the use of this natural product as phytotherapeutical agent.CNPq (Brasil), número de proyecto PV 400001/2009 8

    A genetic variant in the catechol-O-methyl transferase (COMT) gene is related to age-dependent differences in the therapeutic effect of calcium-channel blockers.

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    Hypertension is the leading risk factor for cardiovascular disease and one of the major health concerns worldwide. Genetic factors impact both the risk for hypertension and the therapeutic effect of antihypertensive drugs. Sex- and age-specific variances in the prevalence of hypertension are partly induced by estrogen. We investigated 6 single nucleotide polymorphisms in genes encoding enzymes involved in estrogen metabolism in relation to sex- and age-specific differences in the systolic and diastolic blood pressure (SBP and DBP) outcome under the treatment of diuretics, calcium-channel blockers (CCBs), angiotensin-converting-enzyme inhibitors, and angiotensin-receptor blockers (ARBs).We included 5064 subjects (age: 40-82) from the population-based CoLaus cohort. Participants were genotyped for the catechol-O-methyltransferase gene (COMT) variants rs4680, rs737865, and rs165599; the uridine-diphospho-glucuronosyltransferase 1A gene family (UGT1A) variants rs2070959 and rs887829; and the aromatase gene (CYP19A1) variant rs10046. Binomial and linear regression analyses were performed correcting for age, sex, body mass index, smoking, diabetes, and antihypertensive therapy to test whether the variants in focus are significantly associated with BP.All investigated COMT variants were strongly associated with the effect of diuretics, CCBs, and ARBs on SBP or DBP (P &lt; .05), showing an additive effect when occurring in combination. After Bonferroni correction the polymorphism rs4680 (ValMet) in COMT was significantly associated with lower SBP in participants treated with CCBs (P = .009) with an especially strong impact in elderly individuals (age ≥ 70) alone (Δ = -14.08 mm Hg, P = .0005).These results underline the important role of estrogens and catecholamines in hypertension and the importance of genotype dependent, age-related adjustments of calcium-channel blocker treatment

    Continuous variable entanglement and quantum state teleportation between optical and macroscopic vibrational modes through radiation pressure

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    We study an isolated, perfectly reflecting, mirror illuminated by an intense laser pulse. We show that the resulting radiation pressure efficiently entangles a mirror vibrational mode with the two reflected optical sideband modes of the incident carrier beam. The entanglement of the resulting three-mode state is studied in detail and it is shown to be robust against the mirror mode temperature. We then show how this continuous variable entanglement can be profitably used to teleport an unknown quantum state of an optical mode onto the vibrational mode of the mirror.Comment: 18 pages, 10 figure

    Chronic lymphocytic leukemia patients with IGH translocations are characterized by a distinct genetic landscape with prognostic implications

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    Chromosome 14q32 rearrangements/translocations involving the immunoglobulin heavy chain (IGH) are rarely detected in chronic lymphocytic leukemia (CLL). The prognostic significance of the IGH translocation is controversial and its mutational profile remains unknown. Here, we present for the first time a comprehensive next-generation sequencing (NGS) analysis of 46 CLL patients with IGH rearrangement (IGHR-CLLs) and we demonstrate that IGHR-CLLs have a distinct mutational profile with recurrent mutations in NOTCH1, IGLL5, POT1, BCL2, FBXW7, ZMYM3, MGA, BRAF and HIST1H1E genes. Interestingly, BCL2 and FBXW7 mutations were significantly associated with this subgroup and almost half of BCL2, IGLL5 and HISTH1E mutations reported were previously identified in non-Hodgkin lymphomas. Notably, IGH/BCL2 rearrangements were associated with a lower mutation frequency and carried BCL2 and IGLL5 mutations, while the other IGHR-CLLs had mutations in genes related to poor prognosis (NOTCH1, SF3B1 and TP53) and shorter time to first treatment (TFT). Moreover, IGHR-CLLs patients showed a shorter TFT than CLL patients carrying 13q-, normal fluorescence in situ hybridization (FISH) and +12 CLL, being this prognosis particularly poor when NOTCH1, SF3B1, TP53, BIRC3 and BRAF were also mutated. The presence of these mutations not only was an independent risk factor within IGHR-CLLs, but also refined the prognosis of low-risk cytogenetic patients (13q-/normal FISH). Hence, our study demonstrates that IGHR-CLLs have a distinct mutational profile from the majority of CLLs and highlights the relevance of incorporating NGS and the status of IGH by FISH analysis to refine the risk-stratification CLL model

    Actividad antioxidante y polifenoles de las algas marinas halimeda opuntia y halimeda monile

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    En este trabajo se estudió la actividad antioxidante de dos especies de algas marinas (H. opuntia y H. monile) mediante el ensayo de atrapamiento de radicales DPPH• y el sistema β-Caroteno-acido linoleico. Adicionalmente a las fracciones de ácidos fenolicos libres, ésteres solubles y ésteres insolubles de ácidos fenólicos se les determinó el contenido en fenoles totales mediante la técnica de Folin-Ciocalteu y posteriormente se identificaron y cuantificaron 8 ácidos fenólicos y cinámicos, resultando el componente mayoritario el ácido salicílico. En los ensayos utilizados se obtuvieron valores altos de actividad antioxidante para las diferentes fracciones. A partir de estos resultados se puede postular que la actividad antioxidante de los extractos polares de estas algas pudiera ser explicada, al menos parcialmente, por la presencia de los ácidos fenólicos y cinámicos. En el caso del alga Halimeda monile, de acuerdo con la literatura consultada, es el primer reporte de la actividad antioxidante.In this paper, the antioxidant activity displayed by two different green seaweed species (H. opuntia y H. monile) was studied using the β- carotene/ linoleic acid and the DPPH• scavenging.systems as different experimental in vitro antioxidant assessment models. Polar seaweed fractions containing free phenolic acids, soluble esters and insoluble esters of phenolic acids were chemically characterized in terms of their phenolic content and composition. In that direction, 8 phenolic acids were identified and quantified, and salycilic acid was shown to be the majoritary compound on the fractions from both species. In addition, the polar fractions were proved to exert antioxidant activity in the two used experimental systems with considerably low values of CI50. Thus, in view of these findings, the antioxidant activity of these polar Halimeda spp. extracts could be supported and at least partially related to the presence of phenolic acids. In case of Halimeda monile this is, at least to the extend of our knowledge, the first report of such biological activity
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