Penetration of ultraviolet‐B radiation in oligotrophic regions of the oceans during the Malaspina 2010 expedition

Few studies have investigated ultraviolet (UV) radiation in the open ocean besides its harmful effects on organisms and influence on biogeochemical processes. Here, we assessed UV attenuation, with particular focus on UV‐B, across the (sub)tropical ocean during the Malaspina 2010 Circumnavigation. Vertical UV radiometer profiles together with Chl‐ a concentration, and UV absorption by CDOM ( a CDOM ( λ )) and by suspended particulate matter ( a p ( λ )) were measured at 117 stations. At photosynthetically active radiation (PAR) and across UV‐A and UV‐B wavelengths, the lowest downwelling attenuation coefficients ( K d ) during the expedition were recorded in ultra‐oligotrophic regions at 5°–15°S (mean K d (305 nm): 0.129 m −1 , mean K d (313 nm): 0.107 m −1 ) in the Indian and South Pacific Oceans. The waters here were comparatively more transparent than at 5°–15°N (mean K d (305 nm): 0.239 m −1 , mean K d (313 nm): 0.181 m −1 ) where equatorial upwelling occurs. K d was highest near the Costa Rica Dome ( K d (313 nm): 0.226 m −1 ) and at the confluence of the Benguela and Agulhas currents ( K d (313 nm): 0.251 m −1 ). The contribution of a p ( λ ) toward nonwater absorption ( a nw ( λ )) was significantly lower at 305 nm than at 313 and 320 nm, suggesting the contribution of absorption by detritus and phytoplankton particles decreases compared with that of CDOM absorption as UV‐B wavelength decreases. Both a CDOM ( λ ) and a p ( λ ) at UV‐B wavelengths were lowest in the Indian Ocean whereas K d was lowest in the South Pacific. This finding emphasizes that other factors besides absorption, such as scattering by reflective phytoplankton or inorganic particles, strongly influence UV‐B attenuation in open ocean waters.Plain Language Summary: We assessed water transparency to UV‐B radiation across the tropical and subtropical ocean as part of the Malaspina 2010 Expedition. UV‐B radiometer profiles, Chlorophyll‐a, and UV‐B absorption by organic matter and suspended particles were measured at 117 stations. The most UV‐B transparent waters were found in regions where nutrients are extremely low, particularly at 5°–15°S in the Indian and South Pacific Oceans. Here, ocean waters were considerably more transparent than 5°–15°N, which suggests that at a given depth southern hemisphere marine organisms experience higher UV‐B exposure than their northern counterparts. The least UV‐B transparent waters were near the Costa Rica Dome and at the confluence of the Benguela and Agulhas currents. UV‐B absorption by organic matter and suspended particles, and Chl‐ a concentration were lowest in the Indian Ocean. The contribution of suspended particles toward nonwater absorption was significantly lower at 305 nm than at 313 and 320 nm, and higher in the clearest waters of the Indian Ocean than in the Subtropical South Pacific. Absorptions by organic matter and suspended particles were lowest in the Indian Ocean whereas UV‐B attenuation was lowest in the South Pacific, which highlights the complex relationship between optical properties in the UV‐B spectrum.Ministerio de Ciencia e Innovación | Ref. CSD2008-00077King Abdullah University of Science and Technology | Ref. BAS/1/1072-01-0

Evolution of the HIV-1 nef gene in HLA-B*57 Positive Elite Suppressors

Elite controllers or suppressors (ES) are HIV-1 infected patients who maintain viral loads of < 50 copies/ml without antiretroviral therapy. CD8+ T cells are thought to play a key role in the control of viral replication and exert selective pressure on gag and nef in HLA-B*57 positive ES. We previously showed evolution in the gag gene of ES which surprisingly was mostly due to synonymous mutations rather than non-synonymous mutation in targeted CTL epitopes. This finding could be the result of structural constraints on Gag, and we therefore examined the less conserved nef gene. We found slow evolution of nef in plasma virus in some ES. This evolution is mostly due to synonymous mutations and occurs at a rate similar to that seen in the gag gene in the same patients. The results provide further evidence of ongoing viral replication in ES and suggest that the nef and gag genes in these patients respond similarly to selective pressure from the host

Antimicrobial activity of a 3D-printed polymethylmethacrylate dental resin enhanced with graphene

The present study aimed to test, in vitro, the antimicrobial activity against Candida albicans and Streptococcus mutans and the surface roughness of a 3D-printed polymethylmethacrylate dental resin enhanced with graphene. A 3D-printed polymethylmethacrylate dental resin was reinforced with four different concentrations of graphene: 0.01, 0.1, 0.25 and 0.5 wt%. Neat resin was used as a control. The specimens were printed in a liquid crystal display printer. Disc specimens were used in antimicrobial evaluation, and bar-shaped specimens were used to measure surface roughness. The study of antimicrobial activity included the inhibition of the growth of C. albicans and S. mutans and their adhesion to the resin’s surface. Surface roughness increased with the increase in the graphene concentration. The growth inhibition of C. albicans was observed in the different concentrations of graphene after 24 h, with no recovery after 48 h. The specimens doped with graphene were capable of inactivating S. mutans after 48 h. The surface-adhesion studies showed that the density of microbial biofilms decreases in the case of specimens doped with graphene. Graphene, despite increasing the resin’s surface roughness, was effective in inhibiting the growth and the adhesion to the resin’s surface of the main inducers of prosthetic stomatitis.info:eu-repo/semantics/publishedVersio

Genetic Screening of Mutations Associated with Fabry Disease in a Nationwide Cohort of Juvenile Idiopathic Arthritis Patients

Fabry's disease (FD) is a lysosomal storage disorder associated with an alpha-galactosidase A deficiency. The prevalence of FD among juvenile idiopathic arthritis (JIA) patients with established diagnosis is unknown, but as musculoskeletal pain may be an important complaint at presentation, misdiagnosed cases are anticipated. With this study, we aim to calculate the frequency of FD-associated mutations in a cohort of JIA patients. Children with JIA from a national cohort were selected. Clinical and laboratorial information was recorded in the Portuguese rheumatic diseases register (http://Reuma.pt). Molecular genetic testing to detectGLAgene mutations was performed. After the multiplex polymerase chain reactions technique for DNA amplification, direct sequencing of the complete sequence ofGLAgene was completed. From a cohort of 292 patients with JIA (188 females, 104 males), mutations were identified in 5 patients (all female). Four patients had the mutation D313Y, a rareGLAvariant, which is associated with low enzymatic levels in plasma, but normal lysosomal levels. One patient presented the missense mutation R118C, which was previously described in Mediterranean patients with FD. This is the first screening of FD mutations in a cohort of JIA patients. No "classic" pathogenic FD mutations were reported. The late-onset FD-associated mutation, R118C, was found in a frequency of 0.34% (1/292).publishersversionpublishe

Dust tracking techniques applied to the STARDUST facility: First results

An important issue related to future nuclear fusion reactors fueled with deuterium and tritium is the creation of large amounts of dust due to several mechanisms (disruptions, ELMs and VDEs). The dust size expected in nuclear fusion experiments (such as ITER) is in the order of microns (between 0.1 and 1000 μm). Almost the total amount of this dust remains in the vacuum vessel (VV). This radiological dust can re-suspend in case of LOVA (loss of vacuum accident) and these phenomena can cause explosions and serious damages to the health of the operators and to the integrity of the device. The authors have developed a facility, STARDUST, in order to reproduce the thermo fluid-dynamic conditions comparable to those expected inside the VV of the next generation of experiments such as ITER in case of LOVA. The dust used inside the STARDUST facility presents particle sizes and physical characteristics comparable with those that created inside the VV of nuclear fusion experiments. In this facility an experimental campaign has been conducted with the purpose of tracking the dust re-suspended at low pressurization rates (comparable to those expected in case of LOVA in ITER and suggested by the General Safety and Security Report ITER-GSSR) using a fast camera with a frame rate from 1000 to 10,000 images per second. The velocity fields of the mobilized dust are derived from the imaging of a two-dimensional slice of the flow illuminated by optically adapted laser beam. The aim of this work is to demonstrate the possibility of dust tracking by means of image processing with the objective of determining the velocity field values of dust re-suspended during a LOVA

Pre-miRNA-149 G-quadruplex as a molecular agent to capture nucleolin

PD/BD/142851/2018 PD/00065/2013 MIT-EXPL/BIO/0008/2017 IF/00959/2015One of the most significant challenges in capturing and detecting biomarkers is the choice of an appropriate biomolecular receptor. Recently, RNA G-quadruplexes emerged as plausible receptors due to their ability to recognize with high-affinity proteins. Herein, we have unveiled and characterized the capability of the precursor microRNA 149 to form a G-quadruplex structure and determined the role that some ligands may have in its folding and binding capacity to nucleolin. The G-quadruplex formation was induced by K+ ions and stabilized by ligands, as demonstrated by nuclear magnetic resonance and circular dichroism experiments. Surface plasmon resonance measurements showed a binding affinity of precursor microRNA 149 towards ligands in the micromolar range (10−5–10−6 M) and a strong binding affinity to nucleolin RNA-binding domains 1 and 2 (8.38 × 10−10 M). Even in the presence of the ligand PhenDC3, the binding remains almost identical and in the same order of magnitude (4.46 × 10−10 M). The molecular interactions of the RNA G-quadruplex motif found in precursor miRNA 149 (5′-GGGAGGGAGGGACGGG- 3′) and nucleolin RNA-binding domains 1 and 2 were explored by means of molecular docking and molecular dynamics studies. The results showed that RNA G-quadruplex binds to a cavity between domains 1 and 2 of the protein. Then, complex formation was also evaluated through polyacrylamide gel electrophoresis. The results suggest that precursor microRNA 149/ligands and precursor microRNA 149/nucleolin RNA-binding domains 1 and 2 form stable molecular complexes. The in vitro co-localization of precursor microRNA 149 and nucleolin in PC3 cells was demonstrated using confocal microscopy. Finally, a rapid and straightforward microfluidic strategy was employed to check the ability of precursor microRNA 149 to capture nucleolin RNA-binding domains 1 and 2. The results revealed that precursor microRNA 149 can capture nucleolin RNA-binding domains 1 and 2 labeled with Fluorescein 5-isothiocyanate in a concentration-dependent manner, but PhenDC3 complexation seems to decrease the ability of precursor microRNA 149 to capture the protein. Overall, our results proved the formation of the G-quadruplex structure in the precursor microRNA 149 and the ability to recognize and detect nucleolin. This proof-of-concept study could open up a new framework for developing new strategies to design improved molecular receptors for capture and detection of nucleolin in complex biological samples.publishersversionpublishe

Exposure of Secondary School Adolescents from Argentina and Mexico to Smoking Scenes in Movies: a Population-based Estimation

Introducción: Las escenas de consumo de tabaco en películas promueve el inicio del tabaquismo en adolescentes, por lo que el análisis de la cantidad de imágenes de tabaco en películas que realmente llega a los adolescentes se ha convertido en un tema de interés creciente.Objetivo: Estimar el nivel de exposición a imágenes de tabaco contenidas en películas vistas por adolescentes de la Argentina y México.Material y métodos: Se realizó una encuesta a alumnos de primer año de nivel secundario de la Argentina y México. Se analizaron las 100 películas con mayor recaudación en cada año del período 2009-2013 (Argentina) y 2010-2014 (México).A cada participante se le asignó una muestra aleatoria de 50 de estas películas, preguntándosele si la había visto. Se estimó el número total de adolescentes que habían visto cada película en cada país y se multiplicó por el número de escenas que contenían tabaco (ocurrencias) en cada película para así obtener el número de impresiones crudas de tabaco vistas por los adolescentes escolarizados de cada país.Resultados: Se analizaron 422 films en la Argentina y 433 en México. Más de 500 millones de imágenes de tabaco fueron vistas por la población joven de cada país, lo que promedia 128 y 121 minutos de escenas con tabaquismo por cada adolescente en la Argentina y México, respectivamente. Si bien los films calificados para mayores de 15/16/18 años tenían mayor promedio por película de escenas de tabaco, las películas calificadas para menores de esta edad fueron responsables de la mayor cantidad de escenas de tabaquismo vistas por adolescentes (67,3% en la Argentina y 54,4% en México) debido a su mayor audiencia.Conclusión: A nivel poblacional, las películas para niños son las máximas responsables de la carga de tabaco vista por adolescentes.Background: Smoking scenes in movies promote adolescent smoking onset; thus, the analysis of the number of images of smoking in movies really reaching adolescents has become a subject of increasing interest. Objective: The aim of this study was to estimate the level of exposure to images of smoking in movies watched by adolescents in Argentina and Mexico. Methods: First-year secondary school students from Argentina and Mexico were surveyed. One hundred highest-grossing films from each year of the period 2009-2013 (Argentina) and 2010-2014 (Mexico) were analyzed. Each participant was assigned a random sample of 50 of these movies and was asked if he/she had watched them. The total number of adolescents who had watched each movie in each country was estimated and was multiplied by the number of smoking scenes (occurrences) in each movie to obtain the number of gross smoking impressions seen by secondary school adolescents from each country. Results: Four-hundred and twenty-two movies were analyzed in Argentina and 433 in Mexico. Exposure to more than 500 million smoking impressions was estimated for adolescents in each country, averaging 128 and 121 minutes of smoking scenes seen by each Argentine and Mexican adolescent, respectively. Although 15, 16 and 18-rated movies had more smoking scenes in average, movies rated for younger teenagers were responsible for the highest number of smoking scenes watched by the students (67.3% in Argentina and 54.4% in Mexico) due to their larger audience. Conclusion: At the population level, movies aimed at children are responsible for the highest tobacco burden seen by adolescents.Fil: Salgado, Maria Victoria. Centro de Estudios de Estado y Sociedad; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pérez, Adriana Alicia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Centro de Estudios de Estado y Sociedad; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Abad Vivero, Erika N. Instituto Nacional de Salud Pública; MéxicoFil: Thrasher, James F.. Instituto Nacional de Salud Pública; México. University Of South Carolina; Estados UnidosFil: Sargent, James D.. Geisel School Of Medicine At Dartmouth; Estados UnidosFil: Mejia, Raul Mariano. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina. Centro de Estudios de Estado y Sociedad; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin