898 research outputs found

    Análise da aplicabilidade da Infraestrutura Nacional de Dados Espaciais (INDE) para dados vetoriais em escalas grandes

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    Este trabalho é parte de uma pesquisa sobre Infraestrutura de Dados Espaciais (IDE). Com o objetivo de evitar a duplicidade de ações e o desperdício de recursos na obtenção de dados geoespaciais, o Governo Brasileiro iniciou, em 2003, estudos sistemáticos com o objetivo de integrar e padronizar os dados espaciais produzidos por diferentes instituições federais. O Decreto 6.666, aprovado em 27 de novembro de 2008, estabeleceu a Infraestrutura Nacional de Dados Espaciais (INDE). A padronização da estrutura de dados espaciais e de metadados proposta pela INDE atende as escalas padrão de 1:25.000, 1:50.000, 1:100.000, 1:250.000 e 1:100.0000 da Cartografia Sistemática Brasileira. O mapeamento topográfico em escalas maiores que 1:25.000, no entanto, ainda carece de uma legislação em âmbito federal para sua normatização. A adoção das normas e padrões propostos pela INDE para projetos cartográficos em escalas grandes significa um avanço nesse sentido e atende à recomendação do Plano de Ação da INDE. Ao considerar a importância dos dados espaciais em escalas grandes para os diferentes setores da sociedade brasileira que utilizam informação espacial, o principal objetivo dessa pesquisa é analisar a aplicabilidade das normas e padrões de dados e de metadados propostos pela INDE, para o mapeamento topográfico em escalas grandes. A metodologia de trabalho adotada compreende o levantamento e a análise das feições mapeadas, a definição da relação destas feições com as categorias, classes, subclasses e atributos de objetos, de acordo com os padrões da INDE, a implementação da base de dados espaciais e a associação dos metadados, para uma área piloto na escala 1:2.000. Os dados utilizados no desenvolvimento deste trabalho referem-se a 123 cartas topográficas na escala 1:2.000. Com os resultados obtidos, verifica-se que as feições representadas em cartas de escalas grandes, como no caso desta pesquisa, podem ser estruturadas de acordo com o modelo de dados e o padrão de metadados propostos na INDE, o que confirma sua aplicabilidade para escalas grandes. Pelo maior grau de detalhamento, inerente à representação de feições na escala 1:2.000, novas classes, novos atributos e novos domínios de atributo foram criados

    Cytochrome P450 1 genes in birds : evolutionary relationships and transcription profiles in chicken and Japanese quail embryos

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    © The Author(s), 2011. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS One 6 (2011): e28257, doi:10.1371/journal.pone.0028257.Cytochrome P450 1 (CYP1) genes are biomarkers for aryl hydrocarbon receptor (AHR) agonists and may be involved in some of their toxic effects. CYP1s other than the CYP1As are poorly studied in birds. Here we characterize avian CYP1B and CYP1C genes and the expression of the identified CYP1 genes and AHR1, comparing basal and induced levels in chicken and quail embryos. We cloned cDNAs of chicken CYP1C1 and quail CYP1B1 and AHR1. CYP1Cs occur in several bird genomes, but we found no CYP1C gene in quail. The CYP1C genomic region is highly conserved among vertebrates. This region also shares some synteny with the CYP1B region, consistent with CYP1B and CYP1C genes deriving from duplication of a common ancestor gene. Real-time RT-PCR analyses revealed similar tissue distribution patterns for CYP1A4, CYP1A5, CYP1B1, and AHR1 mRNA in chicken and quail embryos, with the highest basal expression of the CYP1As in liver, and of CYP1B1 in eye, brain, and heart. Chicken CYP1C1 mRNA levels were appreciable in eye and heart but relatively low in other organs. Basal transcript levels of the CYP1As were higher in quail than in chicken, while CYP1B1 levels were similar in the two species. 3,3′,4,5,5′-Pentachlorobiphenyl induced all CYP1s in chicken; in quail a 1000-fold higher dose induced the CYP1As, but not CYP1B1. The apparent absence of CYP1C1 in quail, and weak expression and induction of CYP1C1 in chicken suggest that CYP1Cs have diminishing roles in tetrapods; similar tissue expression suggests that such roles may be met by CYP1B1. Tissue distribution of CYP1B and CYP1C transcripts in birds resembles that previously found in zebrafish, suggesting that these genes serve similar functions in diverse vertebrates. Determining CYP1 catalytic functions in different species should indicate the evolving roles of these duplicated genes in physiological and toxicological processes.Funding to MEJ and BB was from the Carl Tryggers Stiftelse and The Swedish Research Council Formas. Funding for BRW and JJS was from the United States National Institutes of Health (National Institute of Environmental Health Sciences), grants R01ES015912 and P42ES007381 to JJS

    Transcriptional profiling of rat hypothalamus response to 2,3,7,8-tetrachlorodibenzo-p-dioxin

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    In some mammals, halogenated aromatic hydrocarbon (HAH) exposure causes wasting syndrome, defined as significant weight loss associated with lethal outcomes. The most potent HAH in causing wasting is 2,3,7,8-tetrachlorodibenzo-rho-dioxin (TCDD), which exerts its toxic effects through the aryl hydrocarbon receptor (AHR). Since TCDD toxicity is thought to predominantly arise from dysregulation of AHR-transcribed genes, it was hypothesized that wasting syndrome is a result of to TCDD-induced dysregulation of genes involved in regulation of food-intake. As the hypothalamus is the central nervous systems' regulatory center for food-intake and energy balance. Therefore, mRNA abundances in hypothalamic tissue from two rat strains with widely differing sensitivities to TCDD-induced wasting syndrome: TCDD-sensitive Long-Evans rats and TCDD-resistant Han/Wistar rats, 23 h after exposure to TCDD (100 mu g/kg) or corn oil vehicle. TCDD exposure caused minimal transcriptional dysregulation in the hypothalamus, with only 6 genes significantly altered in Long-Evans rats and 15 genes in Han/Wistar rats. Two of the most dysregulated genes were Cyp1a1 and Nqo1, which are induced by TCDD across a wide range of tissues and are considered sensitive markers of TCDD exposure. The minimal response of the hypothalamic transcriptome to a lethal dose of TCDD at an early time-point suggests that the hypothalamus is not the predominant site of initial events leading to hypophagia and associated wasting. TCDD may affect feeding behaviour via events upstream or downstream of the hypothalamus, and further work is required to evaluate this at the level of individual hypothalamic nuclei and subregions. (C) 2014 The Authors. Published by Elsevier Ireland Ltd.Peer reviewe

    ZIP8 Zinc Transporter: Indispensable Role for Both Multiple-Organ Organogenesis and Hematopoiesis In Utero

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    Previously this laboratory characterized Slc39a8-encoded ZIP8 as a Zn2+/(HCO3–)2 symporter; yet, the overall physiological importance of ZIP8 at the whole-organism level remains unclear. Herein we describe the phenotype of the hypomorphic Slc39a8(neo/neo) mouse which has retained the neomycin-resistance gene in intron 3, hence causing significantly decreased ZIP8 mRNA and protein levels in embryo, fetus, placenta, yolk sac, and several tissues of neonates. The Slc39a8(neo) allele is associated with diminished zinc and iron uptake in mouse fetal fibroblast and liver-derived cultures; consequently, Slc39a8(neo/neo) newborns exhibit diminished zinc and iron levels in several tissues. Slc39a8(neo/neo) homozygotes from gestational day(GD)-11.5 onward are pale, growth-stunted, and die between GD18.5 and 48 h postnatally. Defects include: severely hypoplastic spleen; hypoplasia of liver, kidney, lung, and lower limbs. Histologically, Slc39a8(neo/neo) neonates show decreased numbers of hematopoietic islands in yolk sac and liver. Low hemoglobin, hematocrit, red cell count, serum iron, and total iron-binding capacity confirmed severe anemia. Flow cytometry of fetal liver cells revealed the erythroid series strikingly affected in the hypomorph. Zinc-dependent 5-aminolevulinic acid dehydratase, required for heme synthesis, was not different between Slc39a8(+/+) and Slc39a8(neo/neo) offspring. To demonstrate further that the mouse phenotype is due to ZIP8 deficiency, we bred Slc39a8(+/neo) with BAC-transgenic BTZIP8-3 line (carrying three extra copies of the Slc39a8 allele); this cross generated viable Slc39a8(neo/neo)_BTZIP8-3(+/+) pups showing none of the above-mentioned congenital defects–proving Slc39a8(neo/neo) causes the described phenotype. Our study demonstrates that ZIP8-mediated zinc transport plays an unappreciated critical role during in utero and neonatal growth, organ morphogenesis, and hematopoiesis
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