859 research outputs found

    Foliar water uptake in Amazonian trees: evidence and consequences

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    This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordThe absorption of atmospheric water directly into leaves enables plants to alleviate the water stress caused by low soil moisture, hydraulic resistance in the xylem and the effect of gravity on the water column, while enabling plants to scavenge small inputs of water from leaf-wetting events. By increasing the availability of water, and supplying it from the top of the canopy (in a direction facilitated by gravity), foliar uptake (FU) may be a significant process in determining how forests interact with climate, and could alter our interpretation of current metrics for hydraulic stress and sensitivity. FU has not been reported for lowland tropical rainforests; we test whether FU occurs in six common Amazonian tree genera in lowland Amazînia, and make a first estimation of its contribution to canopy–atmosphere water exchange. We demonstrate that FU occurs in all six genera and that dew-derived water may therefore be used to “pay” for some morning transpiration in the dry season. Using meteorological and canopy wetness data, coupled with empirically derived estimates of leaf conductance to FU (kfu), we estimate that the contribution by FU to annual transpiration at this site has a median value of 8.2% (103 mm/year) and an interquartile range of 3.4%–15.3%, with the biggest sources of uncertainty being kfu and the proportion of time the canopy is wet. Our results indicate that FU is likely to be a common strategy and may have significant implications for the Amazon carbon budget. The process of foliar water uptake may also have a profound impact on the drought tolerance of individual Amazonian trees and tree species, and on the cycling of water and carbon, regionally and globally.Natural Environment Research Council (NERC)Australian Research Council (ARC)CNPQEuropean Union FP7Royal SocietyCoordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES

    Microbial Translocation Is Associated with Extensive Immune Activation in Dengue Virus Infected Patients with Severe Disease

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    Background:Severe dengue virus (DENV) disease is associated with extensive immune activation, characterized by a cytokine storm. Previously, elevated lipopolysaccharide (LPS) levels in dengue were found to correlate with clinical disease severity. In the present cross-sectional study we identified markers of microbial translocation and immune activation, which are associated with severe manifestations of DENV infection.Methods:Serum samples from DENV-infected patients were collected during the outbreak in 2010 in the State of SĂŁo Paulo, Brazil. Levels of LPS, lipopolysaccharide binding protein (LBP), soluble CD14 (sCD14) and IgM and IgG endotoxin core antibodies were determined by ELISA. Thirty cytokines were quantified using a multiplex luminex system. Patients were classified according to the 2009 WHO classification and the occurrence of plasma leakage/shock and hemorrhage. Moreover, a (non-supervised) cluster analysis based on the expression of the quantified cytokines was applied to identify groups of patients with similar cytokine profiles. Markers of microbial translocation were linked to groups with similar clinical disease severity and clusters with similar cytokine profiles.Results:Cluster analysis indicated that LPS levels were significantly increased in patients with a profound pro-inflammatory cytokine profile. LBP and sCD14 showed significantly increased levels in patients with severe disease in the clinical classification and in patients with severe inflammation in the cluster analysis. With both the clinical classification and the cluster analysis, levels of IL-6, IL-8, sIL-2R, MCP-1, RANTES, HGF, G-CSF and EGF were associated with severe disease.Conclusions:The present study provides evidence that both microbial translocation and extensive immune activation occur during severe DENV infection and may play an important role in the pathogenesis

    Tularaemia: A challenging zoonosis

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    In recent years, several emerging zoonotic vector-borne infections with potential impact on human health have been identified in Europe, including tularaemia, caused by Francisella tularensis.This remarkable pathogen, one of the most virulent microorganisms currently known, has been detected in increasingly new settings and in a wide range of wild species, including lagomorphs, rodents, carnivores, fish and invertebrate arthropods. Also, a renewed concern has arisen with regard to F. tularensis: its potential use by bioterrorists. Based on the information published concerning the latest outbreaks, the aim of this paper is to review the main features of the agent, its biology, immunology and epidemiology. Moreover, special focus will be given to zoonotic aspects of the disease, as tularaemia outbreaks in human populations have been frequently associated with disease in animals

    Energy and Flux Measurements of Ultra-High Energy Cosmic Rays Observed During the First ANITA Flight

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    The first flight of the Antarctic Impulsive Transient Antenna (ANITA) experiment recorded 16 radio signals that were emitted by cosmic-ray induced air showers. For 14 of these events, this radiation was reflected from the ice. The dominant contribution to the radiation from the deflection of positrons and electrons in the geomagnetic field, which is beamed in the direction of motion of the air shower. This radiation is reflected from the ice and subsequently detected by the ANITA experiment at a flight altitude of 36km. In this paper, we estimate the energy of the 14 individual events and find that the mean energy of the cosmic-ray sample is 2.9 EeV. By simulating the ANITA flight, we calculate its exposure for ultra-high energy cosmic rays. We estimate for the first time the cosmic-ray flux derived only from radio observations. In addition, we find that the Monte Carlo simulation of the ANITA data set is in agreement with the total number of observed events and with the properties of those events.Comment: Added more explanation of the experimental setup and textual improvement

    The Genome Sequence Of Leishmania (leishmania) Amazonensis: Functional Annotation And Extended Analysis Of Gene Models

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    We present the sequencing and annotation of the Leishmania (Leishmania) amazonensis genome, an etiological agent of human cutaneous leishmaniasis in the Amazon region of Brazil. L. (L.) amazonensis shares features with Leishmania (L.) mexicana but also exhibits unique characteristics regarding geographical distribution and clinical manifestations of cutaneous lesions (e.g. borderline disseminated cutaneous leishmaniasis). Predicted genes were scored for orthologous gene families and conserved domains in comparison with other human pathogenic Leishmania spp. Carboxypeptidase, aminotransferase, and 3â€Č-nucleotidase genes and ATPase, thioredoxin, and chaperone-related domains were represented more abundantly in L. (L.) amazonensis and L. (L.) mexicana species. Phylogenetic analysis revealed that these two species share groups of amastin surface proteins unique to the genus that could be related to specific features of disease outcomes and host cell interactions. Additionally, we describe a hypothetical hybrid interactome of potentially secreted L. (L.) amazonensis proteins and host proteins under the assumption that parasite factors mimic their mammalian counterparts. The model predicts an interaction between an L. (L.) amazonensis heat-shock protein and mammalian Toll-like receptor 9, which is implicated in important immune responses such as cytokine and nitric oxide production. The analysis presented here represents valuable information for future studies of leishmaniasis pathogenicity and treatment. © The Author 2013.206567581(2010) Control of the Leishmaniasis WHOTechnical Report Series, , WHO. WHO Press: GenevaLainson, R., Shaw, J.J., (1987) The leishmaniases in biology and medicine. Evolution, classification and geographical distributionBates, P.A., Transmission of Leishmania metacyclic promastigotes by phlebotomine sand flies (2007) Int. J. Parasitol., 37, pp. 1097-1106Dedet, J.P., Pratlong, F., Lanotte, G., Ravel, C., Cutaneous leishmaniasis The parasite (1999) Clin. Dermatol., 17, pp. 261-268Murray, H.W., Berman, J.D., Davies, C.R., Saravia, N.G., Advances in leishmaniasis (2005) Lancet, 366, pp. 1561-1577Camara Coelho, L.I., Paes, M., Guerra, J.A., Characterization of Leishmania spp causing cutaneous leishmaniasis in Manaus, Amazonas, Brazil (2011) Parasitol. Res., 108, pp. 671-677Silveira, F.T., Lainson, R., Corbett, C.E., Further observations on clinical, histopathological, and immunological features of borderline disseminated cutaneous leishmaniasis caused by Leishmania (Leishmania) amazonensis (2005) Mem Inst Oswaldo Cruz, 100, pp. 525-534Real, F., Mortara, R.A., The diverse and dynamic nature of Leishmania parasitophorous vacuoles studied by multidimensional imaging (2012) PLoS Negl. Trop. Dis., 6, pp. e1518Real, F., Pouchelet, M., Rabinovitch, M., Leishmania (L) amazonensis: Fusion between parasitophorous vacuoles in infected bone-marrow derived mousemacrophages (2008) Exp Parasitol., 119, pp. 15-23Alpuche-Aranda, C.M., Racoosin, E.L., Swanson, J.A., Miller, S.I., Salmonella stimulate macrophage macropinocytosis and persist within spacious phagosomes (1994) J. Exp. Med., 179, pp. 601-608Real, F., Mortara, R.A., Rabinovitch, M., Fusion between Leishmania amazonensis and Leishmania major parasitophorous vacuoles: Live imaging of coinfected macrophages (2010) PLoS Negl. Trop. Dis., 4, pp. e905Ndjamen, B., Kang, B.H., Hatsuzawa, K., Kima, P.E., Leishmania parasitophorous vacuoles interact continuously with the host cell's endoplasmic reticulumparasitophorous vacuoles are hybrid compartments (2010) Cell Microbiol., 12, pp. 1480-1494Clayton, C., Shapira, M., Post-Transcriptional regulation of gene expression in trypanosomes and leishmanias (2007) Mol. Biochem. Parasitol., 156, pp. 93-101Martinez-Calvillo, S., Yan, S., Nguyen, D., Fox, M., Stuart, K., Myler, P.J., Transcription of Leishmania major Friedlin chromosome 1 initiates in both directions within a single region (2003) Mol. Cell, 11, pp. 1291-1299Haile, S., Papadopoulou, B., Developmental regulation of gene expression in trypanosomatid parasitic protozoa (2007) Curr. Opin. Microbiol., 10, pp. 569-577Martinez-Calvillo, S., Vizuet-de-Rueda, J.C., Florencio- Martinez, L.E., Manning-Cela, R.G., Figueroa-Angulo, E.E., Gene expression in trypanosomatid parasites (2010) J. Biomed. Biotechnol., 2010, p. 525241Wincker, P., Ravel, C., Blaineau, C., The Leishmania genome comprises 36 chromosomes conserved across widely divergent human pathogenic species (1996) Nucleic Acids Res., 24, pp. 1688-1694Britto, C., Ravel, C., Bastien, P., Conserved linkage groups associated with large-scale chromosomal rearrangements between Old World and New World Leishmania genomes (1998) Gene, 222, pp. 107-117Peacock, C.S., Seeger, K., Harris, D., Comparative genomic analysis of three Leishmania species that cause diverse human disease (2007) Nat. Genet., 39, pp. 839-847Raymond, F., Boisvert, S., Roy, G., Genome sequencing of the lizard parasite Leishmania tarentolae reveals loss of genes associated to the intracellular stage of human pathogenic species (2012) Nucleic Acids Res., 40, pp. 1131-1147Rovai, L., Tripp, C., Stuart, K., Simpson, L., Recurrent polymorphisms in small chromosomes of Leishmania tarentolae after nutrient stress or subcloning (1992) Mol. Biochem. Parasitol., 50, pp. 115-125Ivens, A.C., Peacock, C.S., Worthey, E.A., The genome of the kinetoplastid parasite Leishmania major (2005) Science, 309, pp. 436-442Downing, T., Imamura, H., Decuypere, S., Whole genome sequencing of multiple Leishmania donovani clinical isolates provides insights into population structure and mechanisms of drug resistance (2011) Genome Res., 21, pp. 2143-2156Rogers, M.B., Hilley, J.D., Dickens, N.J., Chromosome and gene copy number variation allow major structural change between species and strains of Leishmania (2011) Genome Res., 21, pp. 2129-2142Smith, D.F., Peacock, C.S., Cruz, A.K., Comparative genomics: Fromgenotype to disease phenotype in the leishmaniases (2007) Int. J. Parasitol., 37, pp. 1173-1186Lye, L.F., Owens, K., Shi, H., Retention and loss of RNA interference pathways in trypanosomatid protozoans (2010) PLoS Pathog., 6, pp. e1001161Messing, J., Crea, R., Seeburg, P.H., A system for shotgun DNA sequencing (1981) Nucleic Acids Res., 9, pp. 309-321Zerbino, D.R., Birney, E., Velvet: Algorithms for de novo short read assembly using de Bruijn graphs (2008) Genome Res., 18, pp. 821-829Quinn, N.L., Levenkova, N., Chow, W., Assessing the feasibility of GS FLX Pyrosequencing for sequencing the Atlantic salmon genome (2008) BMC Genomics, 9, p. 404Sommer, D.D., Delcher, A.L., Salzberg, S.L., Pop, M., Minimus: A fast, lightweight genome assembler BMC Bioinformatics, 8, p. 64Pop, M., Kosack, D.S., Salzberg, S.L., Hierarchical scaffolding with Bambus (2004) Genome Res., 14, pp. 149-159Slater, G.S., Birney, E., Automated generation of heuristics for biological sequence comparison (2005) BMC Bioinformatics, 6, p. 31Salzberg, S.L., Delcher, A.L., Kasif, S., White, O., Microbial gene identification using interpolated Markov models (1998) Nucleic Acids Res., 26, pp. 544-548Lomsadze, A., Ter-Hovhannisyan, V., Chernoff, Y.O., Borodovsky, M., Gene identification in novel eukaryotic genomes by self-Training algorithm (2005) Nucleic Acids Res., 33, pp. 6494-6506Haas, B.J., Salzberg, S.L., Zhu, W., Automated eukaryotic gene structure annotation using EVidence Modeler and the program to assemble spliced alignments (2008) Genome Biol., 9, pp. R7Koski, L.B., Gray, M.W., Lang, B.F., Burger, G., AutoFACT: An automatic functional annotation and classification tool (2005) BMC Bioinformatics, 6, p. 151Suzek, B.E., Huang, H., McGarvey, P., Mazumder, R., Wu, C.H., UniRef: Comprehensive and non-redundant UniProt reference clusters (2007) Bioinformatics, 23, pp. 1282-1288Marchler-Bauer, A., Bryant, S.H., CD-Search: Protein domain annotations on the fly (2004) Nucleic Acids Res., 32, pp. W327-W331Bateman, A., Birney, E., Cerruti, L., The Pfam protein families database (2002) Nucleic Acids Res., 30, pp. 276-280Kanehisa, M., Goto, S., KEGG: Kyoto encyclopedia of genes and genomes (2000) Nucleic Acids Res., 28, pp. 27-30Chen, F., Mackey, A.J., Stoeckert, C.J., Jrand Roos, D.S., OrthoMCL-DB: Querying a comprehensive multi-species collection of ortholog groups (2006) Nucleic Acids Res., 34, pp. D363-D368Chen, F., Mackey, A.J., Vermunt, J.K., Roos, D.S., Assessing performance of orthology detection strategies applied to eukaryotic genomes (2007) PLoS One, 2, pp. e383Quinlan, A.R., Hall, I.M., BEDTools: A flexible suite of utilities for comparing genomic features (2010) Bioinformatics, 26, pp. 841-842Sharp, P.M., Li, W.H., The codon adaptation index - A measure of directional synonymous codon usage bias, and its potential applications (1987) Nucleic Acids Res., 15, pp. 1281-1295Sharp, P.M., Tuohy, T.M., Mosurski, K.R., Codon usage in yeast: Cluster analysis clearly differentiates highly and lowly expressed genes (1986) Nucleic Acids Res., 14, pp. 5125-5143Comeron, J.M., Aguade, M., An evaluation of measures of synonymous codon usage bias (1998) J. Mol. Evol., 47, pp. 268-274Aslett, M., Aurrecoechea, C., Berriman, M., TriTrypDB: A functional genomic resource for the Trypanosomatidae (2010) Nucleic Acids Res., 38, pp. D457-D462Drummond, A.J., Ashton, B., Buxton, S., (2011) Geneious v5.6.3., , http://www.geneious.com/, (June 2012, date last accessed)Edgar, R.C., MUSCLE: Multiple sequence alignment with high accuracy and high throughput (2004) Nucleic Acids Res., 32, pp. 1792-1797Ronquist, F., Huelsenbeck, J.P., MrBayes 3: Bayesian phylogenetic inference under mixed models (2003) Bioinformatics, 19, pp. 1572-1574Whelan, S., Goldman, N., A general empirical model of protein evolution derived from multiple protein families using a maximum-likelihood approach (2001) Mol. Biol. Evol., 18, pp. 691-699Emanuelsson, O., Brunak, S., Von Heijne, G., Nielsen, H., Locating proteins in the cell using TargetP SignalP and related tools Nat. Protoc., 2, pp. 953-971Bendtsen, J.D., Jensen, L.J., Blom, N., Von Heijne, G., Brunak, S., Feature-based prediction of nonclassical and leaderless protein secretion (2004) Protein Eng Des Sel: PEDS, 17, pp. 349-356Paape, D., Barrios-Llerena, M.E., Le Bihan, T., Mackay, L., Aebischer, T., Gel free analysis of the proteome of intracellular Leishmania mexicana (2010) Mol. Biochem. Parasitol., 169, pp. 108-114Lowe, T.M., Eddy, S.R., TRNAscan-SE: A program for improved detection of transfer RNA genes in genomic sequence (1997) Nucleic Acids Res., 25, pp. 955-964Castillo-Ramirez, S., Vazquez-Castellanos, J.F., Gonzalez, V., Cevallos, M.A., Horizontal gene transfer and diverse functional constrains within a common replication- partitioning system in Alphaproteobacteria: The repABC operon (2009) BMC Genomics, 10, p. 536Bastien, P., Blaineau, C., Pages, M., Leishmania: Sex, lies and karyotype (1992) Parasitol. Today, 8, pp. 174-177Mannaert, A., Downing, T., Imamura, H., Dujardin, J.C., Adaptivemechanisms in pathogens: Universal aneuploidy in Leishmania (2012) Trends Parasitol., 28, pp. 370-376Sterkers, Y., Lachaud, L., Bourgeois, N., Crobu, L., Bastien, P., Pages, M., Novel insights intogenomeplasticity in Eukaryotes: Mosaic aneuploidy in Leishmania (2012) Mol. Microbiol., 86, pp. 15-23Ning, Z., Cox, A.J., Mullikin, J.C., SSAHA: A fast search method for large DNA databases (2001) Genome Res., 11, pp. 1725-1729Gentil, L.G., Lasakosvitsch, F., Silveira, J.F., Santos, M.R., Barbieri, C.L., Analysis and chromosomal mapping of Leishmania (Leishmania) amazonensis amastigote expressed sequence tags (2007) Mem Inst Oswaldo Cruz, 102, pp. 707-711Hutson, S., Structure and function of branched chain aminotransferases (2001) Prog Nucleic Acid Res. Mol. Biol., 70, pp. 175-206Ginger, M.L., Chance, M.L., Goad, L.J., Elucidation of carbon sources used for the biosynthesis of fatty acids and sterols in the trypanosomatid Leishmania mexicana (1999) Biochem. J., 342, pp. 397-405Arruda, D.C., D'Alexandri, F.L., Katzin, A.M., Uliana, S.R., Leishmania amazonensis: Biosynthesis of polyprenols of 9 isoprene units by amastigotes Exp. Parasitol., 118, pp. 624-628Neubert, T.A., Gottlieb, M., An inducible 30- nucleotidase/nuclease from the trypanosomatid Crithidia luciliae Purification and characterization (1990) J. Biol. Chem., 265, pp. 7236-7242Paletta-Silva, R., Vieira, D.P., Vieira-Bernardo, R., Leishmania amazonensis: Characterization of an ecto-30-nucleotidase activity and its possible role in virulence (2011) Exp Parasitol., 129, pp. 277-283Holmgren, A., Lu., J., Thioredoxin and thioredoxin reductase: Current research with special reference to human disease, Biochem (2010) Biophys. Res. Commun., 396, pp. 120-124Scott, P., Sher, A., A spectrum in the susceptibility of leishmanial strains to intracellular killing by murine macrophages (1986) J. Immunol., 136, pp. 1461-1466Krauth-Siegel, R.L., Comini, M.A., Redox control in trypanosomatids, parasitic protozoa with trypanothione- based thiol metabolism (2008) Biochim Biophys. Acta, 1780, pp. 1236-1248De Souza Carmo, E.V., Katz, S., Barbieri, C.L., Neutrophils reduce the parasite burden in Leishmania (Leishmania) amazonensis-infected macrophages (2010) PLoS One, 5, pp. e13815Asato, Y., Oshiro, M., Myint, C.K., Phylogenic analysis of the genus Leishmania by cytochrome b gene sequencing (2009) Exp. Parasitol., 121, pp. 352-361Fraga, J., Montalvo, A.M., DeDoncker, S., Dujardin, J.C., Van Der Auwera, G., Phylogeny of Leishmania species based on the heat-shock protein 70 gene (2010) Infect Genet. Evol., 10, pp. 238-245Rochette, A., McNicoll, F., Girard, J., Characterization and developmental gene regulation of a large gene family encoding amastin surface proteins in Leishmania spp (2005) Mol. Biochem. Parasitol., 140, pp. 205-220Jackson, A.P., The evolution of amastin surface glycoproteins in trypanosomatid parasites (2010) Mol. Biol. Evol., 27, pp. 33-45Cruz, M.C., Souza-Melo, N., Da Silva, C.V., Trypanosomacruzi: Role of delta-Amastinonextracellular amastigote cell invasion and differentiation (2012) PLoS One, 7, pp. e51804Stober, C.B., Lange, U.G., Roberts, M.T., From genome to vaccines for leishmaniasis: Screening 100 novel vaccine candidates against murine Leishmania major infection (2006) Vaccine, 24, pp. 2602-2616Rafati, S., Hassani, N., Taslimi, Y., Movassagh, H., Rochette, A., Papadopoulou, B., Amastin peptide-binding antibodies as biomarkers of active human visceral leishmaniasis (2006) Clin. Vaccine Immunol., 13, pp. 1104-1110Salotra, P., Duncan, R.C., Singh, R., Subba Raju, B.V., Sreenivas, G., Nakhasi, H.L., Upregulation of surface proteins in Leishmania donovani isolated from patients of post kala-Azar dermal leishmaniasis (2006) Microbes Infect., 8, pp. 637-644Rochette, A., Raymond, F., Ubeda, J.M., Genome-wide gene expression profiling analysis of Leishmania major and Leishmania infantum developmental stages reveals substantial differences between the two species (2008) BMC Genomics, 9, p. 255Azizi, H., Hassani, K., Taslimi, Y., Najafabadi, H.S., Papadopoulou, B., Rafati, S., Searching for virulence factors in the non-pathogenic parasite to humans Leishmania tarentolae (2009) Parasitology, 136, pp. 723-735Naderer, T., McConville, M.J., The Leishmaniamacrophage interaction: A metabolic perspective (2008) Cell Microbiol., 10, pp. 301-308De Souza Leao, S., Lang, T., Prina, E., Hellio, R., Antoine, J.C., Intracellular Leishmania amazonensis amastigotes internalize and degrade MHC class II molecules of their host cells (1995) J. Cell Sci., 108, pp. 3219-3231Silverman, J.M., Chan, S.K., Robinson, D.P., Proteomic analysis of the secretome of Leishmania donovani (2008) Genome Biol., 9, pp. R35Mouchess, M.L., Arpaia, N., Souza, G., Transmembrane mutations in Toll-like receptor 9 bypass the requirement for ectodomain proteolysis and induce fatal inflammation (2011) Immunity, 35, pp. 721-732Tuon, F.F., Fernandes, E.R., Pagliari, C., Duarte, M.I., Amato, V.S., The expression of TLR9 in human cutaneous leishmaniasis is associated with granuloma (2010) Parasite Immunol., 32, pp. 769-772Abou Fakher, F.H., Rachinel, N., Klimczak, M., Louis, J., Doyen, N., TLR9-dependent activation of dendritic cells byDNA fromLeishmania major favors Th1 cell development and the resolution of lesions (2009) J. Immunol., 182, pp. 1386-1396Carvalho, L.P., Petritus, P.M., Trochtenberg, A.L., Lymph node hypertrophy following Leishmania major infection is dependent on TLR9 (2012) J. Immunol., 188, pp. 1394-1401Favali, C., Tavares, N., Clarencio, J., Barral, A., Barral- Netto, M., Brodskyn, C., Leishmania amazonensis infection impairs differentiation and function of human dendritic cells (2007) J. Leukoc. Biol., 82, pp. 1401-1406Lezama-Davila, C.M., Isaac-Marquez, A.P., Systemic cytokine response in humans with chiclero's ulcers (2006) Parasitol Res., 99, pp. 546-553Linares, E., Augusto, O., Barao, S.C., Giorgio, S., Leishmania amazonensis infection does not inhibit systemic nitric oxide levels elicited by lipopolysaccharide in vivo (2000) J. Parasitol., 86, pp. 78-8
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