Evaluation of a novel microfluidic immuno-magnetic agglutination assay method for detection of dengue virus NS1 antigen

BACKGROUND: Dengue virus (DENV) is the most important arbovirus worldwide, causing infections in endemic countries and returning travellers from these areas. Rapid diagnostic tests are needed to improve patient management and monitor local transmission. The detection of DENV non-structural protein 1 (NS1) is a useful tool for the diagnosis, but the currently available methods can be time consuming or lack sensitivity. The objective of our study was to evaluate a new rapid and semi-quantitative microfluidic DENV NS1 immuno-magnetic agglutination assay based on aggregation of magnetic nanoparticles detected by an electronic reader (Virotrack Dengue Acute and Blubox, Blusense diagnostics, Copenhagen, Denmark). METHODOLOGY/PRINCIPAL FINDINGS: A panel of 135 serum samples from travelers returning from dengue endemic countries was analyzed (74 DENV positive samples including the four DENV serotypes, 26 Zika virus positive samples, 25 chikungunya virus positive samples, 5 malaria positive samples and 5 negative samples). Samples were tested by three different antigen detection methods: SD Dengue NS1 Ag ELISA, SD BIOLINE Dengue Duo and ViroTrack Dengue Acute. The sensitivity observed for SD Dengue NS1 Ag ELISA, ViroTrack Dengue Acute and SD BIOLINE Dengue Duo was 97.2%, 91.1% and 68.1%, respectively. All methods showed high specificity (98.4% for ViroTrack Dengue Acute and 100% for both SD Dengue NS1 Ag ELISA and SD BIOLINE Dengue Duo). SD Dengue NS1 Ag ELISA and ViroTrack Dengue Acute only failed to detect samples positive for DENV-2. CONCLUSIONS/SIGNIFICANCE: ViroTrack Dengue Acute is a sensitive and specific assay for DENV NS1 detection. It provides faster results than the ELISA method and a better performance than the rapid immunochromatographic tests. ViroTrack Dengue Acute could represent a valuable tool for rapid diagnosis of DENV infections in returning travellers from endemic countries

La renovación de la palabra en el bicentenario de la Argentina : los colores de la mirada lingüística

El libro reúne trabajos en los que se exponen resultados de investigaciones presentadas por investigadores de Argentina, Chile, Brasil, España, Italia y Alemania en el XII Congreso de la Sociedad Argentina de Lingüística (SAL), Bicentenario: la renovación de la palabra, realizado en Mendoza, Argentina, entre el 6 y el 9 de abril de 2010. Las temáticas abordadas en los 167 capítulos muestran las grandes líneas de investigación que se desarrollan fundamentalmente en nuestro país, pero también en los otros países mencionados arriba, y señalan además las áreas que recién se inician, con poca tradición en nuestro país y que deberían fomentarse. Los trabajos aquí publicados se enmarcan dentro de las siguientes disciplinas y/o campos de investigación: Fonología, Sintaxis, Semántica y Pragmática, Lingüística Cognitiva, Análisis del Discurso, Psicolingüística, Adquisición de la Lengua, Sociolingüística y Dialectología, Didáctica de la lengua, Lingüística Aplicada, Lingüística Computacional, Historia de la Lengua y la Lingüística, Lenguas Aborígenes, Filosofía del Lenguaje, Lexicología y Terminología

Environmental evolution and mid–late Holocene climate events in the Valencia lagoon (Mediterranean coast of Spain)

Integration of geomorphological, stratigraphic, malacological, sedimentological and micropalaeontological techniques and 14C dating allows us to characterise the processes and evolution of the coastal barrier–lagoon system of Valencia (Spain), from the middle Holocene to the historical epoch, as well as the responses to global climate events. Four stages are recognised. Phase 1: around 8240 ± 80 cal. yr BP, a brackish lagoon of moderate energy and in restricted environment was formed, with an energy peak that could correspond to the maximum Holocene marine transgression. Dating (8240 ± 80 cal. yr BP) carried out in peat corresponds to a cold cycle and low water levels in inland lakes of the western Mediterranean. Phase 2: from 6450 cal. yr BP to 3710 ± 130 cal. yr BP, a lagoon remained, in restricted environment and connected with the sea, but with a notable energy decrease and recurrent saturation processes similar to those described in other Mediterranean continental lakes. This phase is contemporaneous with a period of increase in the aridity trend and global cold cycles. Phase 3: from 3710 ± 130 cal. yr BP, a brackish lagoon without marine connection was formed. Towards 820 ± 90 cal. yr BP, a shift to a totally isolated lagoon environment took place (changing from brackish lagoon to freshwater). This process is coeval with a palaeohydrological phase of high flooding frequency in the river flood plains of Spain and Southern France. Phase 4: freshwater lagoon environment becomes a widespread flood plain. During a phase of high frequency and magnitude of floods (‘Little Ice Age’), the flood plain is formed on the top level of the sequence. Phases and processes recorded in sedimentation could be placed in relation with global mid-to-late Holocene events.This work was supported by grant CSO 2012-32367, Department of Scientific and Technical Research. Ministry of Economy and Competitiveness (Spain). ‘Hydrogeomorphological processes and changes in Mediterranean coastal flood plains. Climate variability and human actions. A multiscale approach’. This work was partially carried out thanks to the support of Labex OT-Med (ANR-11-LABX-0061) and the A*MIDEX project (no. ANR-11- IDEX-0001-02), funded by the French Government’s ‘Investissements d’Avenir’ programme, managed by the French National Research Agency (ANR).Ciencias del Ma

Complete Characterization of Stratified Ecosystems of the Salar de Llamara (Atacama Desert)

Salar de Llamara is situated in the north of the Atacama Desert, which is the driest desert and one of the most irradiated places on Earth. Besides, its subterranean hypersaline waters contain a high content of arsenic, among other compounds such as heavy metals that are poisonous to life in the concentrations present. Despite these extreme conditions, diverse microbial communities flourish in gypsum stratified ecosystems (microbial mats and evaporitic domes).Here, we reviewed all the analysis carried out in these communities, involving taxonomic and functional studies by culture-independent techniques, analysis of the physicochemical parameters of the water and its relation with the microbial ecosystems, together with pigments, mineralogy, and the microscopic view.Regarding taxonomy, the major points analyzed were: (1) the taxonomic trends at phylum level showed that Proteobacteria and Bacteroidetes were the major components of these communities. (2) A low proportion of sequences associated with the phylum Cyanobacteria were detected in all the studied samples. (3) The increased proportion of sequences that could not be affiliated with any taxonomic group that is deposited in the databases. (4) The large amount of rare phyla represented by candidate phyla, such as OD1, OP1, OD8, Hyd24-12, and NKB19.The functional analysis, carried out in these gypsum evaporite systems, revealed that there was only a minor presence of oxygenic photosynthesizers in the community, and anoxygenic photosynthesis appears as an alternative for primary production. Since the Calvin?Benson cycle was scant, the low abundance of oxygenic photosynthesizers was also related to unusual carbon fixation pathways.Regarding physicochemical parameters of the water, the most interesting results were: (1) a huge amount of arsenic; (2) high salinity; (3) low nutrients and high levels of some ions, such as sodium, sulfate, and calcium. The low dissolved oxygen in most of the set points was low, which was consistent with the low proportion of oxygenic photosynthesizers in all the samples studied.Regarding the mineralogy, gypsum mainly compounded all the evaporitic domes, and the microbial mats present halite as the main mineral component.Fil: Rasuk, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Contreras Leiva, Manuel. Centro de Ecología Aplicada; ChileFil: Kurth, Daniel German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Farias, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentin