155 research outputs found

    Composición y distribución de las asociaciones de crustáceos submareales e intermareales en fondos blandos de la Ría de Vigo (NO España)

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    The intertidal and subtidal soft-bottoms of the inner area of the Ria de Vigo (NW Spain) were sampled in November and December 1999, and spatial distribution of crustacean species was examined. Environmental variables from water and sediment were measured at each sampling site. Amphipods and myocopids were the numerically dominant orders (49.9 and 26.9% dominance), amphipods accounting for more than 54% of identified taxa. The highest crustacean densities occurred with 55-41 species and 5953.6-4346.4 ind. m–2 in external areas, where the diversity index reached the maximum values. Multivariate techniques revealed that distribution of crustaceans in the inlet was highly dependent on depth. Ordination analysis determined three major assemblages: Intertidal bottoms colonized by seagrasses and subjected to strong variations of salinity were dominated by the amphipod Melita palmata, harpacticoids and the isopod Idotea baltica (Group A). The amphipod Corophium cf. runcicorne and the cumacean Iphinoe tenella predominated in the muddy bottoms of central areas (Group B). These species were also present in the deep muddy bottoms of the mouth of the inlet, with high carbonate and gravel contents, and with the myocopids and the amphipod Microdeutopus cf. armatus displaying maximum dominances (Group C).Los fondos blandos intermareales y submareales de la parte interna de la Ría de Vigo (NO España) fueron estudiados en relación a la distribución de los crustáceos y a las variables ambientales asociadas a sus aguas y sedimentos. Los anfípodos y miocópidos fueron los órdenes más abundantes (49.9 y 26.9%), presentando los anfípodos más del 54% de los taxa identificados. Las mayores densidades de crustáceos aparecieron en las áreas externas, con 55-41 especies y 5953.6-4346.4 individuos por m2, alcanzándose aquí los máximos valores de diversidad. Se emplearon técnicas multivariantes para analizar los datos, demostrando que la distribución de los crustáceos en la ensenada dependía principalmente de la profundidad. Se observaron tres principales asociaciones de crustáceos: Los fondos intermareales, colonizados por las fanerógamas marinas Zostera marina y Z. noltii y sometidos a drásticos cambios de salinidad, estuvieron dominados por el anfípodo Melita palmata, los harpacticoideos y el isópodo Idotea baltica (Grupo A). El anfípodo Corophium cf. runcicorne y el cumáceo Iphinoe tenella predominaron en los fondos fangosos de la zona central (Grupo B). Estas especies también estuvieron presentes en los fondos profundos de la boca de la ensenada, donde los miocópidos y el anfípodo Microdeutopus cf. armatus presentaron sus máximas dominancias (Grupo C)

    Distribución espacial de la macrofauna bentónica de sedimentos submareales de la Ría de Aldán (Galicia, Noroeste de España)

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    In the summer of 1997, 27 subtidal stations were quantitatively sampled in the Ría de Aldán. A total of 81770 individuals were collected, comprising 496 species. The distribution and composition of benthic assemblages was correlated to the sedimentary characteristics which, in turn, depend on the hydrodynamic features; those patterns are reflected in a sedimentary gradient present along the ria, which is characterized by an increasing grain size from the inner margins towards the mouth. Several faunal assemblages were determined through multivariate analyses and their composition is compared with that of several communities or facies previously described from similar sediments. The Venus fasciata community was present in clean coarse sediments of the outer ria, the Venus gallina and Tellina fabula-Tellina tenuis communities in the fine-sand bottoms at the centre and margins of the ria, a transition assemblage between the Venus fasciata and the Venus gallina communities in the medium-sand sediments, and a mix of species from the Syndosmya alba and the Amphiura communities in shallower and muddy sediments in the inner areas. In general, subtidal sediments of the Ría de Aldán showed a high benthic diversity which is related to the great sedimentary heterogeneity and the lack of significant anthropogenic alterations.Durante el verano de 1997, se hicieron muestreos en 27 estaciones submareales de modo cuantitativo en la Ría de Aldán. Se recolectaron un total de 81770 individuos, pertenecientes a 496 especies. Los análisis multivariantes permitieron distinguir varias asociaciones faunísticas cuya composición puede ser referida a comunidades o facies previamente descritas de sedimentos similares: la comunidad de “Venus fasciata” está presente en sedimentos limpios de granulometría gruesa de la parte externa de la ría, las comunidades de “Venus gallina” y “Tellina fabula-Tellina tenuis” aparecen principalmente en arena fina en las áreas marginal y central, una fauna de transición entre las comunidades de V. fasciata y V. gallina se encuentra en fondos de arena media, y los fondos someros fangosos de la zona interna están caracterizados por una mezcla de especies propias de las comunidades de “Syndosmya alba” y “Amphiura”. En general, los sedimentos submareales de la Ría de Aldán presentaron una alta diversidad bentónica relacionada con la gran heterogeneidad sedimentaria y la ausencia de perturbaciones humanas significativas

    Ecological features of Terebellida fauna (Annelida, Polychaeta) from Ensenada de San Simón (NW Spain)

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    Ecological features of Terebellida (Annelida, Polychaeta) inhabiting the intertidal and subtidal soft-bottoms of Ensenada de San Simón (NW Spain) were analysed by means of quantitative sampling. A total of 4,814 specimens belonging to five families (Ampharetidae, Pectinariidae, Terebellidae, Trichobranchidae and Sabellariidae) and ten species were collected in a variety of substrata and depths. Ampharetidae was the numerically dominant family mostly due to the abundance of Ampharete finmarchica and Melinna palmata; these species accounted for up to 94% of the total Terebellida abundance. Intertidal areas colonised by the seagrasses Zostera marina L. and Z. noltii Hornem. One thousand eight hundred and thirty-two harboured low densities of Terebellida, whereas the deeper subtidal muddy bottoms showed high abundances of ampharetids. Multivariate analyses suggested that Terebellida assemblages are highly correlated with sediment composition

    Ecological features of Terebellida fauna (Annelida, Polychaeta) from Ensenada de San Simón (NW Spain)

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    Ecological features of Terebellida (Annelida, Polychaeta) inhabiting the intertidal and subtidal soft-bottoms of Ensenada de San Simon (NW Spain) were analysed by means of quantitative sampling. A total of 4,814 specimens belonging to five families (Ampharetidae, Pectinariidae, Terebellidae, Trichobranchidae and Sabellariidae) and ten species were collected in a variety of substrata and depths. Ampharetidae was the numerically dominant family mostly due to the abundance of Ampharete finmarchica and Melinna palmata; these species accounted for up to 94% of the total Terebellida abundance. Intertidal areas colonised by the seagrasses Zostera marina L. and Z. noltii Hornern. One thousand eight hundred and thirty-two harboured low densities of Terebellida, whereas the deeper subtidal muddy bottoms showed high abundances of ampharetids. Multivariate analyses suggested that Terebellida assemblages are highly correlated with sediment compositio

    Dendrimer-RNA nanoparticles generate protective immunity against lethal Ebola, H1N1 influenza, and

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    Vaccines have had broad medical impact, but existing vaccine technologies and production methods are limited in their ability to respond rapidly to evolving and emerging pathogens, or sudden outbreaks. Here, we develop a rapid-response, fully synthetic, singledose, adjuvant-free dendrimer nanoparticle vaccine platform wherein antigens are encoded by encapsulated mRNA replicons. To our knowledge, this system is the first capable of generating protective immunity against a broad spectrum of lethal pathogen challenges, including H1N1 influenza, Toxoplasma gondii, and Ebola virus. The vaccine can be formed with multiple antigenexpressing replicons, and is capable of eliciting both CD8⁺ T-cell and antibody responses. The ability to generate viable, contaminant-free vaccines within days, to single or multiple antigens, may have broad utility for a range of diseases

    Calmodulin-like proteins localized to the conoid regulate motility and cell invasion by Toxoplasma gondii

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    Toxoplasma gondii contains an expanded number of calmodulin (CaM)-like proteins whose functions are poorly understood. Using a combination of CRISPR/Cas9-mediated gene editing and a plant-like auxin-induced degron (AID) system, we examined the roles of three apically localized CaMs. CaM1 and CaM2 were individually dispensable, but loss of both resulted in a synthetic lethal phenotype. CaM3 was refractory to deletion, suggesting it is essential. Consistent with this prediction auxin-induced degradation of CaM3 blocked growth. Phenotypic analysis revealed that all three CaMs contribute to parasite motility, invasion, and egress from host cells, and that they act downstream of microneme and rhoptry secretion. Super-resolution microscopy localized all three CaMs to the conoid where they overlap with myosin H (MyoH), a motor protein that is required for invasion. Biotinylation using BirA fusions with the CaMs labeled a number of apical proteins including MyoH and its light chain MLC7, suggesting they may interact. Consistent with this hypothesis, disruption of MyoH led to degradation of CaM3, or redistribution of CaM1 and CaM2. Collectively, our findings suggest these CaMs may interact with MyoH to control motility and cell invasion

    Infaunal macrobenthos in the Porcupine Bank (NE Atlantic)

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    The results of the macroinfaunal communities distributions from the annual series surveys PORCUPINE are shown. Those surveys were realized during the months of September and October in the years 2006, 2008, 2009, 2010, 2011, 2012 and 2013 by the Instituto Español de Oceanografía aboard the R /V Vizconde de Eza, within the research project ERDEM. This survey series has as main objective the obtainment of abundance indexes of the benthonic and demersal fauna from Porcupine Bank, west of Ireland, with special attention on the commercial species exploited by the Spanish fleet (hake, angler fish, megrim and norwegian lobster). For the study of the infaunal macrobenthos a total of 50 samples were analyzed from selected places of the Bank, where the bottom characteristics, the climatology or the survey schedule allowed. Samples were taken with an ULSNER box corer with 0.09 m2 of sampling area. Samples for the faunal study were sieved aboard with a 0.5 mm mesh size sieve. The material collected in the sieve was preserved with 8 % formaldehyde neutralized with borax, and stained with Rose Bengal solution for the posterior sorting and identification of fauna. Additional samples were taken to estimate the organic content of the sediment and to perform the granulometric analyses. Once in the laboratory, the granulometry was analyzed following the method recommended by Buchanan (1984); which consists in a combination of dry sieving of the coarse fraction (> 62 µm) and the sedimentation at 20 ºC of the fine fraction (< 62 µm) in a distilled water column. Sediment organic matter content was calculated as the percentage of weight loss by means of 24 hours sample calcination at 500 ºC, after dried it at 100 ºC during the same time. Complementary, in order to obtain a better coverage of the sedimentary types from the study area, more than 350 samples were collected with a net collector coupled to the trawling fishing gear (Baca-GAV 39/52). Globally, the sediments of the majority of the sampled stations are mainly formed by sand, between fine and very fine, except in deep areas of the southeast, where there are large muddy areas with elevated organic content and high selection coefficient. In the north, around the shallowest area, we found thicker sandy sediments, with lower organic content and moderate selection. The macroinfaunal communities from the Porcupine Bank are characterized by the dominance of the faunistic group of polychaetes (68.8 %), mainly represented by the families Owenidae, Spionidae, Paraonidae and Sabellidae. The next in number are the group of molluscs (17.6 %), dominated by the family Kelliellidae, which reaches maximum abundances up to 7520 ind•m-2. The poorest represented groups are the crustaceans (5.0 %), echinoderms (4.3 %) and the “others” (sipunculids, nemertine, etc.), being the latter the least abundant (3.7 %). In relation with the spatial distribution four macroinfaunal groups were indentified in the Porcupine Bank: - Group 1: located in intermediate depth areas, over sandy sediments with low organic content. The infaunal community is dominated by polychaetes from the Owenidae family, mainly represented by the specie Galathowenia oculata. - Group 2: occupies the sandy and low organic content sediments from the shallowest area of the Bank. Polychaetes are the most representative faunistic group, highlighting the dominance of the families Spionidae and Paraonidae. Prionospio fallax and Aricidea wassi are the most representative species of the group. - Group 3: situated in two deep areas in the south area of the Bank with muddy and high organic matter content sediments. It has the lowest infaunal abundance of the study, being dominated by the bivalve molluscs from the family Kelliellidae and by the annelids polychaetes from the family Paraonidae. - Group 4: Is the cluster that includes more stations in throughout the study. It is distributed spatially in the south area of the Bank, in different bathymetries, with the most heterogeneous sediments and moderate organic content. The bivalve molluscs from the Kelliellidae family again become dominant, with Kelliella miliaris reaching abundance over 7500 ind•m-2.IE

    Using a genetically encoded sensor to identify inhibitors of Toxoplasma gondii Ca2+ Signalling

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    This work was supported in part by National Institutes of Health Grants AI-110027 and AI-096836 (to S. N. J. M.) and 1DP5OD017892 (to S. L.).The life cycles of apicomplexan parasites progress in accordance with fluxes in cytosolic Ca2+. Such fluxes are necessary for events like motility and egress from host cells. We used genetically encoded Ca2+ indicators (GCaMPs) to develop a cell-based phenotypic screen for compounds that modulate Ca2+ signaling in the model apicomplexan Toxoplasma gondii. In doing so, we took advantage of the phosphodiesterase inhibitor zaprinast, which we show acts in part through cGMP-dependent protein kinase (protein kinase G; PKG) to raise levels of cytosolic Ca2+. We define the pool of Ca2+ regulated by PKG to be a neutral store distinct from the endoplasmic reticulum. Screening a library of 823 ATP mimetics, we identify both inhibitors and enhancers of Ca2+ signaling. Two such compounds constitute novel PKG inhibitors and prevent zaprinast from increasing cytosolic Ca2+. The enhancers identified are capable of releasing intracellular Ca2+ stores independently of zaprinast or PKG. One of these enhancers blocks parasite egress and invasion and shows strong antiparasitic activity against T. gondii. The same compound inhibits invasion of the most lethal malaria parasite, Plasmodium falciparum. Inhibition of Ca2+-related phenotypes in these two apicomplexan parasites suggests that depletion of intracellular Ca2+ stores by the enhancer may be an effective antiparasitic strategy. These results establish a powerful new strategy for identifying compounds that modulate the essential parasite signaling pathways regulated by Ca2+, underscoring the importance of these pathways and the therapeutic potential of their inhibition.Publisher PDFPeer reviewe

    Using a Genetically Encoded Sensor to Identify Inhibitors of Toxoplasma gondii Ca 2+ Signaling

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    The life cycles of apicomplexan parasites progress in accordance with fluxes in cytosolic Ca2+. Such fluxes are necessary for events like motility and egress from host cells. We used genetically encoded Ca2+ indicators (GCaMPs) to develop a cell-based phenotypic screen for compounds that modulate Ca2+ signaling in the model apicomplexan Toxoplasma gondii. In doing so, we took advantage of the phosphodiesterase inhibitor zaprinast, which we show acts in part through cGMP-dependent protein kinase (protein kinase G; PKG) to raise levels of cytosolic Ca2+. We define the pool of Ca2+ regulated by PKG to be a neutral store distinct from the endoplasmic reticulum. Screening a library of 823 ATP mimetics, we identify both inhibitors and enhancers of Ca2+ signaling. Two such compounds constitute novel PKG inhibitors and prevent zaprinast from increasing cytosolic Ca2+. The enhancers identified are capable of releasing intracellular Ca2+ stores independently of zaprinast or PKG. One of these enhancers blocks parasite egress and invasion and shows strong antiparasitic activity against T. gondii. The same compound inhibits invasion of the most lethal malaria parasite, Plasmodium falciparum. Inhibition of Ca2+-related phenotypes in these two apicomplexan parasites suggests that depletion of intracellular Ca2+ stores by the enhancer may be an effective antiparasitic strategy. These results establish a powerful new strategy for identifying compounds that modulate the essential parasite signaling pathways regulated by Ca2+, underscoring the importance of these pathways and the therapeutic potential of their inhibition

    Impact of cardiovascular risk factors on the clinical presentation and survival of pulmonary embolism without identifiable risk factor

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    Background: The nature of pulmonary embolism (PE) without identifiable risk factor (IRF) remains unclear. The objective of this study is to investigate the potential relationship between cardiovascular risk factors (CVRFs) and PE without IRF (unprovoked) and assess their role as markers of disease severity and prognosis. Methods: A case-control study was performed of patients with PE admitted to our hospital [2010-2019]. Subjects with PE without IRF were included in the cohort of cases, whereas patients with PE with IRF were allocated to the control group. Variables of interest included age, active smoking, obesity, and diagnosis of arterial hypertension, dyslipidemia or diabetes mellitus. Results: A total of 1,166 patients were included in the study, of whom 64.2% had PE without IRF. The risk for PE without IRF increased with age [odds ratio (OR): 2.68; 95% confidence interval (CI): 1.95-3.68], arterial hypertension (OR: 1.63; 95% CI: 1.27-2.07), and dyslipidemia (OR: 1.63; 95% CI: 1.24-2.15). The risk for PE without IRF was higher as the number of CVRF increased, being 3.99 (95% CI: 2.02-7.90) for subjects with >/=3 CVRF. The percentage of high-risk unprovoked PE increased significantly as the number of CVRF rose [0.6% for no CVRF; 23.8% for a CRF, P/=3, P<0.001 (OR: 14.1; 95% CI: 4.06-49.4)]. No significant differences were observed in 1-month survival between cases and controls, whereas differences in 24-month survival reached significance. Conclusions: A relationship was observed between CVRF and PE without IRF, as the risk for unprovoked PE increased with the number of CVRF. In addition, the number of CVRF was associated with PE without IRF severity, but not with prognosis
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