28 research outputs found

    Potential geographic distribution of Hantavirus reservoirs in Brazil

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    Hantavirus cardiopulmonary syndrome is an emerging zoonosis in Brazil. Human infections occur via inhalation of aerosolized viral particles from excreta of infected wild rodents. Necromys lasiurus and Oligoryzomys nigripes appear to be the main reservoirs of hantavirus in the Atlantic Forest and Cerrado biomes. We estimated and compared ecological niches of the two rodent species, and analyzed environmental factors influencing their occurrence, to understand the geography of hantavirus transmission. N. lasiurus showed a wide potential distribution in Brazil, in the Cerrado, Caatinga, and Atlantic Forest biomes. Highest climate suitability for O. nigripes was observed along the Brazilian Atlantic coast. Maximum temperature in the warmest months and annual precipitation were the variables that most influence the distributions of N. lasiurus and O. nigripes, respectively. Models based on occurrences of infected rodents estimated a broader area of risk for hantavirus transmission in southeastern and southern Brazil, coinciding with the distribution of human cases of hantavirus cardiopulmonary syndrome. We found no demonstrable environmental differences among occurrence sites for the rodents and for human cases of hantavirus. However, areas of northern and northeastern Brazil are also apparently suitable for the two species, without broad coincidence with human cases. Modeling of niches and distributions of rodent reservoirs indicates potential for transmission of hantavirus across virtually all of Brazil outside the Amazon Basin

    Mucins and Pathogenic Mucin-Like Molecules Are Immunomodulators During Infection and Targets for Diagnostics and Vaccines

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    Mucins and mucin-like molecules are highly O-glycosylated proteins present on the cell surface of mammals and other organisms. These glycoproteins are highly diverse in the apoprotein and glycan cores and play a central role in many biological processes and diseases. Mucins are the most abundant macromolecules in mucus and are responsible for its biochemical and biophysical properties. Mucin-like molecules cover various protozoan parasites, fungi and viruses. In humans, modifications in mucin glycosylation are associated with tumors in epithelial tissue. These modifications allow the distinction between normal and abnormal cell conditions and represent important targets for vaccine development against some cancers. Mucins and mucin-like molecules derived from pathogens are potential diagnostic markers and targets for therapeutic agents. In this review, we summarize the distribution, structure, role as immunomodulators, and the correlation of human mucins with diseases and perform a comparative analysis of mucins with mucin-like molecules present in human pathogens. Furthermore, we review the methods to produce pathogenic and human mucins using chemical synthesis and expression systems. Finally, we present applications of mucin-like molecules in diagnosis and prevention of relevant human diseases

    Estudos populacionais e filogenéticos de Oligoryzomys nigripes e o status taxonômico de Oligoryzomys utiaritensis (Rodentia, Sigmodontinae)

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    Submitted by Alessandra Portugal ([email protected]) on 2013-09-20T16:04:23Z No. of bitstreams: 1 RAFAEL CARVALHO TORRES.pdf: 4075176 bytes, checksum: 19fc00e0161a371b5fb7c118bba5a10a (MD5)Made available in DSpace on 2013-09-20T16:04:23Z (GMT). No. of bitstreams: 1 RAFAEL CARVALHO TORRES.pdf: 4075176 bytes, checksum: 19fc00e0161a371b5fb7c118bba5a10a (MD5) Previous issue date: 2012Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, BrasilOs roedores neotropicais do gênero Oligoryzomys possuem ampla distribuição geográfica, distribuindo-se por toda América Latina. No Brasil, existem pelo menos 12 espécies, com representantes em todos os domínios morfoclimáticos. Entre essas espécies, Oligoryzomys nigripes possui a distribuição mais ampla, ocorrendo por toda a Mata Atlântica, do Rio Grande do Norte ao Rio Grande do Sul (incluindo regiões adjacentes do Paraguai e Argentina), nos Pampas gaúchos e uruguaios e regiões de Cerrado em São Paulo e Goiás. Membros do gênero Oligoryzomys desempenham papel fundamental na dispersão e transmissão de hantaviroses, e estudos populacionais e filogenéticos de espécies de mamíferos reservatórios ajudam a entender a distribuição e a dinâmica dos ciclos de transmissão da doença. Com esse trabalho, pretendemos estudar a diversidade genética de Oligoryzomys, através de filogenias moleculares com marcadores mitocondriais (genes citocromo b e citocromo oxidase subunidade I) e um marcador nuclear (íntron 7 do gene beta-fibrinogênio); analisar a diversidade intraespecífica de O. nigripes, através de análises populacionais e filogeográficas de subpopulações de Goiás, Espírito Santo, Rio de Janeiro, Minas Gerais, São Paulo, Paraná, Santa Catarina, Rio Grande do Sul e Paraguai, com os dois marcadores mitocondriais citados acima; revisar o status taxônomico de O. utiaritensis, considerado atualmente sinônimo júnior de O. nigripes, através de análises filogenéticas e morfométricas; e investigar se existem inserções nucleares de genes mitocondriais em espécies de Oligoryzomys, um estudo importante levando-se em consideração que a maior parte dos estudos evolutivos desse grupo incluem o sequenciamento de genes mitocondriais. Os resultados mostram que Oligoryzomys é um gênero monofilético, contendo pelo menos quatro grupos de espécies. A diversidade de Oligoryzomys é subestimada, e existem pelo menos quatro espécies não descritas, além da presença de espécies crípticas. Oligoryzomys diferenciou-se dos outros orizomíneos no final do Mioceno e início do Plioceno, há aproximadamente 6,5 milhões de anos, sendo a espécie O. microtis a espécie mais antiga (2,5 milhões de anos) e O. destructor a espécie mais recente (23 mil anos). As análises populacionais indicam uma estruturação genética incipiente entre subpopulações de O. nigripes do Sudeste e Sul do Brasil, mas a diferenciação entre as subpopulações dentro dessas regiões é pequena. A área de diferenciação original de O. nigripes é a região do sul do Brasil, e pelo menos duas frentes de colonização ocorreram: uma em direção ao Paraguai e outra em direção ao centro e sudeste do Brasil. Oligoryzomys utiaritensis é uma espécie válida, distinta de O. nigripes através da morfologia, morfometria, filogenia molecular e citogenética. Existem inserções de sequências mitocondriais no genoma nuclear de pelo menos cinco espécies de Oligoryzomys. Estudos evolutivos devem vir acompanhados de outros tipos de marcadores moleculares, além de informações morfológicas, geográficas e citogenéticas, para um melhor entendimento das relações complexas entre as espécies de Oligoryzomys.The neotropical rodents of genera Oligoryzomys have a wide distribution, extending throughout Latin America. In Brazil, there are at least 12 species, with representatives in all morphoclimatic domains. Among these species, Oligoryzomys nigripes has the widest distribution, occurring throughout Atlantic Forest of Rio Grande do Norte to Rio Grande do Sul (including adjacent areas of Paraguay and Argentina), Pampas from Brazil and Uruguay, and Cerrado regions of São Paulo e Goiás. Some Oligoryzomys species play a fundamental role in the dispersion and transmission of hantaviruses, and population and phylogenetics studies of mammal reservoirs help to understand the distribution and dynamics of disease transmission cycles. In this work, we intend to study the genetic diversity of Oligoryzomys through molecular phylogeny with mitochondrial markers (cytochrome b and cytochrome oxidase subunit I genes) and a nuclear marker (intron 7 of beta-fibrinogen gene); analyze the intraspecific diversity of O. nigripes via population and phylogeographic studies of subpopulations of Goiás, Espírito Santo, Rio de Janeiro, Minas Gerais, São Paulo, Paraná, Santa Catarina, Rio Grande do Sul and Paraguay, with the two mitochondrial markers cited above; review the taxonomic status of O. utiaritensis, currently considered a junior synonym of O. nigripes, by morphometric analyses and molecular phylogenetics; and investigate whether there are insertions of mitochondrial genes in nuclear genome of Oligoryzomys species, a relevant study if we account that the most evolutionary studies of this group relies on sequencing mitochondrial genes. Results showed here indicate that Oligoryzomys is a monophyletic genus, containing at least four groups of species. The diversity of Oligoryzomys is underestimated, and there are at least four undescribed species, and the presence of cryptic species. Oligoryzomys has differentiated from other oryzomyinies in late Miocene and early Pliocene, about 6.5 million years ago, O. microtis is the oldest species (2.5 million years) and O. destructor the most recent (23.000 years). Population analyzes indicate an incipient genetic structure between subpopulations of O. nigripes from southeast and south of Brazil, but differentiation among subpopulations within these regions is small. The original area of original differentiation of O. nigripes is the region of southern Brazil, and there were at least two fronts of colonization: one to Paraguay and another toward center and southeast of Brazil. Oligoryzomys utiaritensis is a valid species, distinct from O. nigripes by morphology, morhometrics, cytogenetics and molecular phylogeny. There are insertions of mitochondrial origin into nuclear genome of at least five species of Oligoryzomys. Evolutionary studies should be followed by other types of molecular markers, and morphological, geographical and cytogenetics data, to a better understanding of the complex relationships among Oligoryzomys species

    Scene reconstruction for storytelling in 360º videos

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    In immersive and interactive contents like 360-degrees videos the user has the control of the camera, which poses a challenge to the content producer since the user may look to where he wants. This paper presents the concept and first steps towards the development of a framework that provides a workflow for storytelling in 360-degrees videos. With the proposed framework it will be possible to connect a sound to a source and taking advantage of binaural audio it will help to redirect the user attention to where the content producer wants. To present this kind of audio, the scenario must be mapped/reconstructed so as to understand how the objects contained in it interfere with the sound waves propagation. The proposed system is capable of reconstructing the scenario from a stereoscopic, still or motion 360-degrees video when provided in an equirectangular projection. The system also incorporates a module that detects and tracks people, mapping their motion from the real world to the 3D world. In this document we describe all the technical decisions and implementations of the system. To the best of our knowledge, this system is the only that has shown the capability to reconstruct scenarios in a large variety of 360 footage and allows for the creation of binaural audio from that reconstruction.This article is a result of the project CHIC - Cooperative Holistic view on Internet and Content (project n◦ 24498), supported by the European Regional Development Fund (ERDF), through the Competitiveness and Internationalization Operational Program (COMPETE 2020) under the PORTUGAL 2020 Partnership Agreement
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