1,208 research outputs found
TNF-α and IL-6 immunohistochemistry in rat renal tissue experimentaly infected with Leptospira interrogans serovar Canicola
Leptospirosis is a public health problem worldwide and its etiology remains unclear. Its pathogenesis involves a complex interaction between host and infecting microorganism. The inflammatory reaction that controls the infection process also underscores many pathophysiological events occurring in leptospirosis. We investigated the presence of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in renal tissues by immunohistochemical and histopathological examination in animals experimentally inoculated with Leptospira serovar Canicola. All the tests were carried out 2, 7, 14, 21 or 28 days after inoculation. Although TNF-α and IL-6 had been detected in tissues throughout the observation period, these cytokines appeared more intensely during the initial phase of infection. Therefore, both TNF-α and IL-6 were associated with the immunopathogenesis of leptospirosis. This profile suggests a high immunocellular response throughout the early infection stages followed by subsequent humoral response.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)São Paulo State University Dentistry School Department of Animal Health and ProductionSão Paulo State University Dentistry School Department of Clinics, Surgery and Animal ReproductionFederal University of São Paulo Department of MedicineUNIFESP, Department of MedicineSciEL
TRY plant trait database - enhanced coverage and open access
Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
Geographic Coincidence of Increased Malaria Transmission Hazard and Vulnerability Occurring at the Periphery of two Tanzanian Villages.
The goal of malaria elimination necessitates an improved understanding of any fine-scale geographic variations in transmission risk so that complementary vector control tools can be integrated into current vector control programmes as supplementary measures that are spatially targeted to maximize impact upon residual transmission. This study examines the distribution of host-seeking malaria vectors at households within two villages in rural Tanzania. Host-seeking mosquitoes were sampled from 72 randomly selected households in two villages on a monthly basis throughout 2008 using CDC light-traps placed beside occupied nets. Spatial autocorrelation in the dataset was examined using the Moran's I statistic and the location of any clusters was identified using the Getis-Ord Gi* statistic. Statistical associations between the household characteristics and clusters of mosquitoes were assessed using a generalized linear model for each species. For both Anopheles gambiae sensu lato and Anopheles funestus, the density of host-seeking females was spatially autocorrelated, or clustered. For both species, houses with low densities were clustered in the semi-urban village centre while houses with high densities were clustered in the periphery of the villages. Clusters of houses with low or high densities of An. gambiae s.l. were influenced by the number of residents in nearby houses. The occurrence of high-density clusters of An. gambiae s.l. was associated with lower elevations while An. funestus was also associated with higher elevations. Distance from the village centre was also positively correlated with the number of household occupants and having houses constructed with open eaves. The results of the current study highlight that complementary vector control tools could be most effectively targeted to the periphery of villages where the households potentially have a higher hazard (mosquito densities) and vulnerability (open eaves and larger households) to malaria infection
Utilization of galactomannan from Gleditsia triacanthos in polysaccharide-based films : effects of interactions between film constituents on film properties
The objective of this work was to evaluate the effect of the concentrations of Gleditsia triacanthos galactomannan and glycerol and the presence of corn oil in the physical properties of edible films. The influence of interactions between those constituents on films' permeability to gases (water vapour, CO2 and O2), solubility in water, mechanical properties and colour was evaluated. The effects of those variables were analysed according to a 23 factorial design; regression coefficients were used to understand the influence of each variable (factor) on the studied properties, and a multifactor model was developed. Results show that galactomannan concentration is the most significant factor affecting the studied properties; moreover, the increase of plasticizer concentration and the presence of oil showed to be the most influent in the particular cases of solubility and transport properties (water vapour permeability and O2 permeability), respectively. These results show that galactomannan films' properties can be tailored to allow their use as alternative to non-biodegradable, non-edible packaging materials.The author M. A. Cerqueira is recipient of a fellowship from Fundacao para a Ciencia e Tecnologia (FCT, SFRH/BPD/72753/2010) and B. W. S. Souza is a recipient of a fellowship from the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior, Brazil (Capes, Brazil)
Uncovering trophic interactions in arthropod predators through DNA shotgun-sequencing of gut contents
Characterizing trophic networks is fundamental to many questions in ecology, but this typically requires painstaking efforts, especially to identify the diet of small generalist predators. Several attempts have been devoted to develop suitable molecular tools to determine predatory trophic interactions through gut content analysis, and the challenge has been to achieve simultaneously high taxonomic breadth and resolution. General and practical methods are still needed, preferably independent of PCR amplification of barcodes, to recover a broader range of interactions. Here we applied shotgun-sequencing of the DNA from arthropod predator gut contents, extracted from four common coccinellid and dermapteran predators co-occurring in an agroecosystem in Brazil. By matching unassembled reads against six DNA reference databases obtained from public databases and newly assembled mitogenomes, and filtering for high overlap length and identity, we identified prey and other foreign DNA in the predator guts. Good taxonomic breadth and resolution was achieved (93% of prey identified to species or genus), but with low recovery of matching reads. Two to nine trophic interactions were found for these predators, some of which were only inferred by the presence of parasitoids and components of the microbiome known to be associated with aphid prey. Intraguild predation was also found, including among closely related ladybird species. Uncertainty arises from the lack of comprehensive reference databases and reliance on low numbers of matching reads accentuating the risk of false positives. We discuss caveats and some future prospects that could improve the use of direct DNA shotgun-sequencing to characterize arthropod trophic networks
f(R) theories
Over the past decade, f(R) theories have been extensively studied as one of
the simplest modifications to General Relativity. In this article we review
various applications of f(R) theories to cosmology and gravity - such as
inflation, dark energy, local gravity constraints, cosmological perturbations,
and spherically symmetric solutions in weak and strong gravitational
backgrounds. We present a number of ways to distinguish those theories from
General Relativity observationally and experimentally. We also discuss the
extension to other modified gravity theories such as Brans-Dicke theory and
Gauss-Bonnet gravity, and address models that can satisfy both cosmological and
local gravity constraints.Comment: 156 pages, 14 figures, Invited review article in Living Reviews in
Relativity, Published version, Comments are welcom
Initial performance of the COSINE-100 experiment
COSINE is a dark matter search experiment based on an array of low background NaI(Tl) crystals located at the Yangyang underground laboratory. The assembly of COSINE-100 was completed in the summer of 2016 and the detector is currently collecting physics quality data aimed at reproducing the DAMA/LIBRA experiment that reported an annual modulation signal. Stable operation has been achieved and will continue for at least 2 years. Here, we describe the design of COSINE-100, including the shielding arrangement, the configuration of the NaI(Tl) crystal detection elements, the veto systems, and the associated operational systems, and we show the current performance of the experiment
Trophic control in the Guadalquivir estuary and neighbouring waters of the Gulf of Cadiz
The Guadalquivir estuary (SW Spain) is a non-stratified estuary with a gradual change in salinity. It supports an important biodiversity and functions as a nursery area for many commercial species (e.g. anchovy) in the Gulf of Cadiz (GoC). The understanding of the interplay between the environmental forcing (bottom-up) and the trophic regulation is essential to understand its functioning in relation to the GoC fisheries. Here, we seek to study the effects of environmental variables and predator-prey interaction (mysid-anchovy) in the estuary and surrounding marine areas with a particular focus on the zooplankton as key intermediaries between primary production and marine fish juveniles. A long-term (18 yr) monitoring program has been carried out in two sites: Tarfia and Bonanza (32 km and 8 km distance from the river mouth respectively). The latter station samples well the marine water masses advected into the estuary during the ebb flow. Our dataset includes mysids, anchovy larvae and juveniles, temperature, salinity, turbidity, freshwater discharges, precipitation and winds. We used time series-analysis (GAMs) to test the trophic, environmental and anthropogenic effects. Temperature was found to have a positive effect on mysids at both stations while salinity showed a positive effect only at Tarfia. Turbidity showed a strong negative effect on the whole estuary and so did the freshwater discharges at Bonanza, which are regulated by a dam. The results indicate that the trophic control in the estuary of the Guadalquivir is resource-driven. Our models also highlight that marine mysids have a positive effect on anchovy
Serum Metabolome and Lipidome Changes in Adult Patients with Primary Dengue Infection
10.1371/journal.pntd.0002373PLoS Neglected Tropical Diseases78
Natural and anthropogenic factors in the Guadalquivir estuary affect the abundance of anchovy in the Gulf of Cadiz (SW Spain)
The Gulf of Cadiz socio-ecosystem is characterized by a focal ecosystem component –the estuary of the Guadalquivir River– that has an in uence on the marine ecosystem –serves as a nursery area– and at the same time concentrates a great number of sectoral human activities. This nursery role particularly affects the anchovy fishery, which is the most economically and culturally important fishery in the region. As a transition zone between terrestrial and marine environments, estuaries are particularly sensitive to human activities, either developed directly at the aquatic environment or its surroundings. A dam 110 km upstream from the river mouth regulates freshwater input (mainly for agriculture purposes) into the estuary with consequences on turbidity and salinity. Using time series analysis on 18 years of monthly data from an estuarine monitoring program we (1) quantify the effects that natural (plankton, temperature, winds) and anthropogenic-influenced variables (freshwater volume, turbidity, salinity) have on the abundance of anchovy larvae and juveniles, and (2) relate the abundance of these estuarine-resident early stages to the abundance of adult anchovy in the sea. Water management stands out as a key node where potentially con icting interests (agriculture, power generation, aquaculture, fisheries) converge. Linking land-based activities to its impact on stock biomass represents the main challenge to ecosystem-based management in this particular regional sea. By focusing on the effects that these activities ultimately have on the anchovy fishery –via recruitment– our study aims to contribute to the process of making the ecosystem approach operational in the Gulf of Cadiz
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