174 research outputs found

    Frequência De Anticorpos Anti-toxoplasma Gondii Em Cães Com Sinais Clínicos Compatíveis Com Toxoplasmose

    Get PDF
    The aim of this study was to detect antibodies against T. gondii in dogs with clinical signs compatible with toxoplasmosis attended in a veterinary hospital. A serological survey was performed in 598 dogs from 1993 to 2013. The IgG antibodies survey against T. gondii was carried out by means of Indirect Fluorescence Antibodies Test (IFAT); samples with titers >16 were considered positive. Among the dogs with clinical signs, 259 (43,31%) were positive for T. gondii with titers varying between 16 to 4096; among the healthy animals, 79 (22.25%) were reagents. The most frequent signals were: neurological (30.43%) and uveitis (8.03%). Among variables race, gender, and age, only the last one affected the observed results with greater frequency f seropositive in elderly dogs. © 2016, Cienc. anim. bras., Goiânia. All rights reserved.17464064

    SOROEPIDEMIOLOGIA E FATORES ASSOCIADOS À TRANSMISSÃO DO Toxoplasma gondii EM SUÍNOS DO NORTE DO PARANÁ

    Get PDF
    Devido à importância do suíno como fonte de infecção da toxoplasmose humana e aos problemas reprodutivos gerados por esta enfermidade, objetivou-se traçar o perfil soroepidemiológico e os fatores associados à transmissão do Toxoplasma gondii no rebanho de suínos da região Norte do Paraná. Coletaram-se amostras de 521 animais (324 matrizes, 157 marrãs e 40 cachaços), de 22 propriedades suinícolas. Foi aplicado um questionário epidemiológico para verificar as características em relação aos manejos adotados. Realizou-se Imunofluorescência Indireta (IFI) para detecção de anticorpos anti-T. gondii (IgG) e considerou-se positivas as amostras que apresentaram título ³ 64. De 521 amostras de soro analisadas pela IFI, resultaram em 15,35% reagentes (80/521), sendo 54 (10,37%) matrizes, 20 (3,83%) marrãs e seis (1,15%) cachaços. A análise das variáveis evidenciou que o sistema de criação intensivo foi um fator de proteção para a presença de T. gondii. Entretanto, o acesso de outros animais ao cocho de ração e ao reservatório de água, a utilização do bebedouro tipo canaleta, presença de lâmina dágua nas baias e a existência de áreas alagadiças, foram fatores que contribuíram para a infecção pelo T. gondii. Serumepidemiology and associated factors on swine transmission of Toxoplasma gondii at Northern Paraná Brazil Abstract Due to the importance of swine as an infection source of toxoplasmosis to man and the reproductive problems that this disease causes, it was defined the prevalence and the factors associated with the transmission of Toxoplasma gondii in swine herds of northern Paraná State. A total of 521 serum samples (324 sows, 157 gilts e 40 boars) from 22 herds were analyzed and an epidemiological questionnaire was applied to obtain the management employed in these properties. The indirect immunofluorescence (IFAT) test was performed to detect anti-T. gondii antibodies (IgG) and titers ³ 64 were considered positive. From the 521 analyzed serum samples, 15.35% (80/521) were reactive for the IFAT test 54 (10.37%) sows, 20 (3.83%) gilts and 6 (1.15%) boars. The statistical analysis has shown that the intensive management system is a protective factor for T. gondii infection. However, the access of other animals to the water and food reservoir, the channels water-thought, the pens with water-blade and the presence of wet areas were factors which contributed to wards the infection by T. gondii

    Cryptosporidium Spp. And Giardia Spp. In Feces And Water And The Associated Exposure Factors On Dairy Farms

    Get PDF
    The aims of this study were to verify the prevalence of Cryptosporidium spp. and Giardia spp. in animal feces and drinking water on dairy farms and to identify a possible relation between the exposure factors and the presence of these parasites. Fecal samples from cattle and humans and water samples were collected on dairy farms in Paraná, Brazil. Analysis of (oo)cysts in the feces was performed by the modified Ziehl-Neelsen staining and centrifugal flotation in zinc sulfate. Test-positive samples were subjected to nested PCR amplification of the 18SSU ribosomal RNA gene for identification of Cryptosporidium and Giardia and of the gp60 gene for subtyping of Cryptosporidium. Microbiological analysis of water was carried out by the multiple-tube method and by means of a chromogenic substrate, and parasitological analysis was performed on 31 samples by direct immunofluorescence and nested PCR of the genes mentioned above. Identification of the species of Cryptosporidium was performed by sequencing and PCR with analysis of restriction fragment length polymorphisms. The prevalence of Giardia and Cryptosporidium was higher in calves than in adults. Among the samples of cattle feces, Cryptosporidium parvum was identified in 41 (64%), C. ryanae in eight (12.5%), C. bovis in four (6.3%), C. andersoni in five (7.8%), and a mixed infection in 20 samples (31.3%). These parasites were not identified in the samples of human feces. Thermotolerant coliform bacteria were identified in 25 samples of water (45.5%). Giardia duodenalis and C. parvum were identified in three water samples. The gp60 gene analysis of C. parvum isolates revealed the presence of two strains (IIaA20G1R1 and IIaA17G2R2) in the fecal samples and one (IIaA17G2R1) in the water samples. The presence of coliforms was associated with the water source, structure and degradation of springs, rain, and turbidity. The prevalence of protozoa was higher in calves up to six months of age. C. parvum and G. duodenalis were identified in the water of dairy farms, as were thermotolerant coliforms; these findings point to the need for guidance on handling of animals, preservation of water sources, and water treatment. © 2017 Toledo et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.12

    Spatial analysis of leptospirosis and toxoplasmosis seroprevalence in the canine population in an area of socioeconomic and environmental vulnerability

    Get PDF
    ABSTRACT Leptospirosis and toxoplasmosis are zoonoses of occupational character that are spread worldwide, mainly in tropical and socioeconomically vulnerable areas. Both diseases have vertebrate hosts, which spread the infectious agent to the environment and are potentially infectious to humans and can progress to fatal cases. The present study reinforces the importance of One Health for the control and prophylaxis of leptospirosis and toxoplasmosis using sentinel animals in areas of socioeconomic vulnerability based on a serological study. A total of 336 blood samples were obtained from the canine population of the urban district, which has high rates of poverty and sanitation. The results were analyzed based on seroreactivity animals and georeferencing by kernel spatial mapping. A total of 43.3% (52/120) of the animals were seroreagents for anti-Leptospira spp., with a predominance of Canicola (35/52 = 67.3%) and Pyrogenes (5/52 = 9.6%), while 52.97% (178/336) of the dogs were seroreactive for anti-Toxoplasma gondii. The presence of seroreagent dogs for both zoonosis alert to the inadequate hygienic-sanitary conditions of the studied region, and highlight the importance of a survey of the social, economic and environmental structure to identify factors related to the links in the epidemiological chain of pathogen transmission and necessary corrective actions

    Simulation techniques for cosmological simulations

    Get PDF
    Modern cosmological observations allow us to study in great detail the evolution and history of the large scale structure hierarchy. The fundamental problem of accurate constraints on the cosmological parameters, within a given cosmological model, requires precise modelling of the observed structure. In this paper we briefly review the current most effective techniques of large scale structure simulations, emphasising both their advantages and shortcomings. Starting with basics of the direct N-body simulations appropriate to modelling cold dark matter evolution, we then discuss the direct-sum technique GRAPE, particle-mesh (PM) and hybrid methods, combining the PM and the tree algorithms. Simulations of baryonic matter in the Universe often use hydrodynamic codes based on both particle methods that discretise mass, and grid-based methods. We briefly describe Eulerian grid methods, and also some variants of Lagrangian smoothed particle hydrodynamics (SPH) methods.Comment: 42 pages, 16 figures, accepted for publication in Space Science Reviews, special issue "Clusters of galaxies: beyond the thermal view", Editor J.S. Kaastra, Chapter 12; work done by an international team at the International Space Science Institute (ISSI), Bern, organised by J.S. Kaastra, A.M. Bykov, S. Schindler & J.A.M. Bleeke

    N-body simulations of gravitational dynamics

    Full text link
    We describe the astrophysical and numerical basis of N-body simulations, both of collisional stellar systems (dense star clusters and galactic centres) and collisionless stellar dynamics (galaxies and large-scale structure). We explain and discuss the state-of-the-art algorithms used for these quite different regimes, attempt to give a fair critique, and point out possible directions of future improvement and development. We briefly touch upon the history of N-body simulations and their most important results.Comment: invited review (28 pages), to appear in European Physics Journal Plu

    Measurements of long-range near-side angular correlations in sNN=5\sqrt{s_{\text{NN}}}=5TeV proton-lead collisions in the forward region

    Get PDF
    Two-particle angular correlations are studied in proton-lead collisions at a nucleon-nucleon centre-of-mass energy of sNN=5\sqrt{s_{\text{NN}}}=5TeV, collected with the LHCb detector at the LHC. The analysis is based on data recorded in two beam configurations, in which either the direction of the proton or that of the lead ion is analysed. The correlations are measured in the laboratory system as a function of relative pseudorapidity, Δη\Delta\eta, and relative azimuthal angle, Δϕ\Delta\phi, for events in different classes of event activity and for different bins of particle transverse momentum. In high-activity events a long-range correlation on the near side, Δϕ0\Delta\phi \approx 0, is observed in the pseudorapidity range 2.0<η<4.92.0<\eta<4.9. This measurement of long-range correlations on the near side in proton-lead collisions extends previous observations into the forward region up to η=4.9\eta=4.9. The correlation increases with growing event activity and is found to be more pronounced in the direction of the lead beam. However, the correlation in the direction of the lead and proton beams are found to be compatible when comparing events with similar absolute activity in the direction analysed.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-040.htm

    Study of the production of Λb0\Lambda_b^0 and B0\overline{B}^0 hadrons in pppp collisions and first measurement of the Λb0J/ψpK\Lambda_b^0\rightarrow J/\psi pK^- branching fraction

    Get PDF
    The product of the Λb0\Lambda_b^0 (B0\overline{B}^0) differential production cross-section and the branching fraction of the decay Λb0J/ψpK\Lambda_b^0\rightarrow J/\psi pK^- (B0J/ψK(892)0\overline{B}^0\rightarrow J/\psi\overline{K}^*(892)^0) is measured as a function of the beauty hadron transverse momentum, pTp_{\rm T}, and rapidity, yy. The kinematic region of the measurements is pT<20 GeV/cp_{\rm T}<20~{\rm GeV}/c and 2.0<y<4.52.0<y<4.5. The measurements use a data sample corresponding to an integrated luminosity of 3 fb13~{\rm fb}^{-1} collected by the LHCb detector in pppp collisions at centre-of-mass energies s=7 TeV\sqrt{s}=7~{\rm TeV} in 2011 and s=8 TeV\sqrt{s}=8~{\rm TeV} in 2012. Based on previous LHCb results of the fragmentation fraction ratio, fΛB0/fdf_{\Lambda_B^0}/f_d, the branching fraction of the decay Λb0J/ψpK\Lambda_b^0\rightarrow J/\psi pK^- is measured to be \begin{equation*} \mathcal{B}(\Lambda_b^0\rightarrow J/\psi pK^-)= (3.17\pm0.04\pm0.07\pm0.34^{+0.45}_{-0.28})\times10^{-4}, \end{equation*} where the first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the branching fraction of the decay B0J/ψK(892)0\overline{B}^0\rightarrow J/\psi\overline{K}^*(892)^0, and the fourth is due to the knowledge of fΛb0/fdf_{\Lambda_b^0}/f_d. The sum of the asymmetries in the production and decay between Λb0\Lambda_b^0 and Λb0\overline{\Lambda}_b^0 is also measured as a function of pTp_{\rm T} and yy. The previously published branching fraction of Λb0J/ψpπ\Lambda_b^0\rightarrow J/\psi p\pi^-, relative to that of Λb0J/ψpK\Lambda_b^0\rightarrow J/\psi pK^-, is updated. The branching fractions of Λb0Pc+(J/ψp)K\Lambda_b^0\rightarrow P_c^+(\rightarrow J/\psi p)K^- are determined.Comment: 29 pages, 19figures. All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-032.htm

    Evidence for the strangeness-changing weak decay ΞbΛb0π\Xi_b^-\to\Lambda_b^0\pi^-

    Get PDF
    Using a pppp collision data sample corresponding to an integrated luminosity of 3.0~fb1^{-1}, collected by the LHCb detector, we present the first search for the strangeness-changing weak decay ΞbΛb0π\Xi_b^-\to\Lambda_b^0\pi^-. No bb hadron decay of this type has been seen before. A signal for this decay, corresponding to a significance of 3.2 standard deviations, is reported. The relative rate is measured to be fΞbfΛb0B(ΞbΛb0π)=(5.7±1.80.9+0.8)×104{{f_{\Xi_b^-}}\over{f_{\Lambda_b^0}}}{\cal{B}}(\Xi_b^-\to\Lambda_b^0\pi^-) = (5.7\pm1.8^{+0.8}_{-0.9})\times10^{-4}, where fΞbf_{\Xi_b^-} and fΛb0f_{\Lambda_b^0} are the bΞbb\to\Xi_b^- and bΛb0b\to\Lambda_b^0 fragmentation fractions, and B(ΞbΛb0π){\cal{B}}(\Xi_b^-\to\Lambda_b^0\pi^-) is the branching fraction. Assuming fΞb/fΛb0f_{\Xi_b^-}/f_{\Lambda_b^0} is bounded between 0.1 and 0.3, the branching fraction B(ΞbΛb0π){\cal{B}}(\Xi_b^-\to\Lambda_b^0\pi^-) would lie in the range from (0.57±0.21)%(0.57\pm0.21)\% to (0.19±0.07)%(0.19\pm0.07)\%.Comment: 7 pages, 2 figures, All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-047.htm
    corecore