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1.
Nature ; 546(7658): 406-410, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28538727

RESUMO

Transmission of Zika virus (ZIKV) in the Americas was first confirmed in May 2015 in northeast Brazil. Brazil has had the highest number of reported ZIKV cases worldwide (more than 200,000 by 24 December 2016) and the most cases associated with microcephaly and other birth defects (2,366 confirmed by 31 December 2016). Since the initial detection of ZIKV in Brazil, more than 45 countries in the Americas have reported local ZIKV transmission, with 24 of these reporting severe ZIKV-associated disease. However, the origin and epidemic history of ZIKV in Brazil and the Americas remain poorly understood, despite the value of this information for interpreting observed trends in reported microcephaly. Here we address this issue by generating 54 complete or partial ZIKV genomes, mostly from Brazil, and reporting data generated by a mobile genomics laboratory that travelled across northeast Brazil in 2016. One sequence represents the earliest confirmed ZIKV infection in Brazil. Analyses of viral genomes with ecological and epidemiological data yield an estimate that ZIKV was present in northeast Brazil by February 2014 and is likely to have disseminated from there, nationally and internationally, before the first detection of ZIKV in the Americas. Estimated dates for the international spread of ZIKV from Brazil indicate the duration of pre-detection cryptic transmission in recipient regions. The role of northeast Brazil in the establishment of ZIKV in the Americas is further supported by geographic analysis of ZIKV transmission potential and by estimates of the basic reproduction number of the virus.


Assuntos
Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia , Zika virus/isolamento & purificação , América/epidemiologia , Número Básico de Reprodução , Brasil/epidemiologia , Variação Genética , Genoma Viral/genética , Humanos , Microcefalia/epidemiologia , Microcefalia/virologia , Epidemiologia Molecular , Filogeografia , Análise Espaço-Temporal , Zika virus/genética , Infecção por Zika virus/epidemiologia
2.
Life Sci ; 170: 93-99, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27919825

RESUMO

AIMS: To understand how thyroid hormone (TH) regulates tissue-specific gene expression in patients with the syndrome of resistance to TH (RTHß), we used a mouse model that replicates the human RTHß, specifically the ∆337T mutation in the thyroid hormone receptor ß (THRß). MAIN METHODS: We investigated the expression of key TH target genes in the pituitary and liver of TRß∆337T and wild type THRß mice by qPCR before and after a T3 suppression test consisting of the administration of increasing concentrations of T3 to hypothyroid mice. KEY FINDINGS: Pituitary Tshb and Cga expression decreased and Gh expression increased in TRß∆337T mice after T3 suppression. The stimulation of positively regulated TH genes was heterogeneous in the liver. Levels of liver Me1 and Thsrp were elevated in TRß∆337T mice after T3 administration. Slc16a2 and Gpd2 did not respond to T3 stimulation in the liver of TRß∆337T mice whereas Dio1 response was lower than that observed in WT mice. Moreover, although Chdh and Upd1 genes were negatively regulated in the liver, the expression of these genes was elevated after T3 suppression. We did not observe significant changes in THRα expression in the liver and pituitary, while THRß levels were diminished in the pituitary and increased in the liver. SIGNIFICANCE: Using a model expressing a THRß unable to bind T3, we showed the expression pattern of liver negative and positive regulated genes by T3.


Assuntos
Regulação da Expressão Gênica , Tri-Iodotironina/metabolismo , Animais , Modelos Animais de Doenças , Regulação para Baixo , Perfilação da Expressão Gênica , Hormônio do Crescimento/metabolismo , Humanos , Hipotireoidismo/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Hipófise/metabolismo , Reação em Cadeia da Polimerase
3.
PLoS One ; 10(10): e0141495, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26513653

RESUMO

In a fibre-reinforced polymer (FRP) structure designed using the emerging damage tolerance and structural health monitoring philosophy, sensors and models that describe crack propagation will enable a structure to operate despite the presence of damage by fully exploiting the material's mechanical properties. When applying this concept to different structures, sensor systems and damage types, a combination of damage mechanics, monitoring technology, and modelling is required. The primary objective of this article is to demonstrate such a combination. This article is divided in three main topics: the damage mechanism (delamination of FRP), the structural health monitoring technology (fibre Bragg gratings to detect delamination), and the finite element method model of the structure that incorporates these concepts into a final and integrated damage-monitoring concept. A novel method for assessing a crack growth/damage event in fibre-reinforced polymer or structural adhesive-bonded structures using embedded fibre Bragg grating (FBG) sensors is presented by combining conventional measured parameters, such as wavelength shift, with parameters associated with measurement errors, typically ignored by the end-user. Conjointly, a novel model for sensor output prediction (virtual sensor) was developed using this FBG sensor crack monitoring concept and implemented in a finite element method code. The monitoring method was demonstrated and validated using glass fibre double cantilever beam specimens instrumented with an array of FBG sensors embedded in the material and tested using an experimental fracture procedure. The digital image correlation technique was used to validate the model prediction by correlating the specific sensor response caused by the crack with the developed model.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Modelos Teóricos , Fibras Ópticas , Plásticos/química , Adesivos/química , Tecnologia de Fibra Óptica/métodos
4.
Arq. bras. med. vet. zootec. (Online) ; 70(3): 897-904, maio-jun. 2018. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-911667

RESUMO

Objetivou-se avaliar o efeito dos fenos de andropogon, buffel e massai em diferentes intervalos de cortes sob consumo, comportamento ingestivo e o desempenho de ovinos. O delineamento experimental foi inteiramente ao acaso. Os tratamentos foram arranjados em fatorial 3x4 (andropogon, buffel e massai x intervalos entre corte de 21, 35, 49 e 63 dias). A interação entre as gramíneas e os intervalos não foi significativa para nenhuma das variáveis estudadas. Os maiores consumos de matéria seca, proteína bruta, fibra em detergente neutro e lignina ocorreram com uso do feno de massai, 3,62; 0,48; 2,03 e 0,22% do peso vivo, respectivamente. Aos 63 dias de intervalo, foram observados os maiores consumos de lignina e os menores de proteína bruta, 0,20 e 0,42%, respectivamente. O menor ganho médio diário (121,1g/dia) e o menor peso final (17,6kg) foram dos animais alimentados com buffel. Não houve diferença para o tempo de alimentação e o ócio, com tempo médio despendido de 4,5 e 11,7h/dia, respectivamente. Os fenos de massai e andropogon promovem maior consumo de matéria seca e maior desempenho de ovinos em confinamento, enquanto o intervalo entre corte até 63 dias não modifica essas respostas.(AU)


The objective of this study was to evaluate the effect of Andropogon, Buffel and Massai on different intervals cuts of intake, ingestion behavior and sheep performance. The experimental design was completely randomized. The treatments were arranged in 3x4 factorial (Andropogon, Buffel and Massai x cut intervals of 21, 35, 49 and 63 days). The interaction between the grasses and the intervals was not significant for any of the studied variables. The highest intakes of dry matter, crude protein, neutral detergent fiber, acid detergent fiber and lignin were for Massai hay, 3.62; 0.48; 2.03 and 0.22% of the live weight, respectively. At 63 days interval, the highest consumption of lignin and lowest crude protein, 0.20 and 0.42%, respectively, were observed. The lowest daily gain (121.1g/day) and final weight gain (17,6kg) were of Buffel fed animals. There was no difference in feeding time and time, with mean time removed from 4.5 and 11.7h day-1, respectively. Hays of Massai and Andropogon promote greater dry matter intake and performance of sheep in confinement, while the cut intervals up to 63 days does not modify these responses.(AU)


Assuntos
Animais , Alimentos/análise , Poaceae , Ovinos/crescimento & desenvolvimento , Comportamento Alimentar
6.
Braz J Biol ; 69(2 Suppl): 735-45, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19738979

RESUMO

The purpose of this study was to update the floristic inventory found in the Upper Paraná River floodplain. Floristic surveys were performed from February 2000 through March 2008, as part of the Brazilian Long-Term Ecological Research Program (PELD/CNPq-Site 6). The material collected was identified from 774 species, 442 genera, and 116 families. The ten families with high species richness were Leguminosae, Poaceae, Rubiaceae, Asteraceae, Euphorbiaceae, Myrtaceae, Cyperaceae, Solanaceae, Sapindaceae, and Orchidaceae, which contributed to 46.1% of the total number of species. Genera with high richness were Solanum, Cyperus, Panicum, Eugenia, Tillandsia, Serjania, Casearia, and Polygonum, which together contributed to 10.2% of the total number of species. These data, combined with information published in 1997, recorded 955 species, 575 genera, and 128 families. These organisms were from several riparian environments and were distributed as herbs, shrubs, trees, climbers and epiphytes. Panicum maximum, Pennisetum purpureum, Ricinus communis, and Urochloa decumbens are considered weeds due to the wide distributions determined for these species. The results presented herein suggest the need to further investigate the control of these potential weed species.


Assuntos
Biodiversidade , Plantas/classificação , Rios , Brasil
7.
Braz. j. biol ; Braz. j. biol;69(2,supl.0): 735-745, June 2009. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-524762

RESUMO

The purpose of this study was to update the floristic inventory found in the Upper Paraná River floodplain. Floristic surveys were performed from February 2000 through March 2008, as part of the Brazilian Long-Term Ecological Research Program (PELD/CNPq -Site 6). The material collected was identified from 774 species, 442 genera, and 116 families. The ten families with high species richness were Leguminosae, Poaceae, Rubiaceae, Asteraceae, Euphorbiaceae, Myrtaceae, Cyperaceae, Solanaceae, Sapindaceae, and Orchidaceae, which contributed to 46.1 percent of the total number of species. Genera with high richness were Solanum, Cyperus, Panicum, Eugenia, Tillandsia, Serjania, Casearia, and Polygonum, which together contributed to 10.2 percent of the total number of species. These data, combined with information published in 1997, recorded 955 species, 575 genera, and 128 families. These organisms were from several riparian environments and were distributed as herbs, shrubs, trees, climbers and epiphytes. Panicum maximum, Pennisetum purpureum, Ricinus communis, and Urochloa decumbens are considered weeds due to the wide distributions determined for these species. The results presented herein suggest the need to further investigate the control of these potential weed species.


Com o objetivo de ampliar os conhecimentos sobre a flora da planície de inundação do Alto Rio Paraná, foram conduzidos inventários florísticos no período de fevereiro de 2000 a março de 2008, incluídos no Programa Brasileiro de Pesquisas Ecológicas de Longa Duração (PELD/CNPq - Sítio 6). O material coletado foi identificado em 774 espécies, 442 gêneros e 116 famílias. As dez famílias de maior riqueza de espécies foram Leguminosae, Poaceae, Rubiaceae, Asteraceae, Euphorbiaceae, Myrtaceae, Cyperaceae, Solanaceae, Sapindaceae e Orchidaceae, que juntas reuniram 46,1 por cento do total do número de espécies. Os gêneros com maior riqueza de espécies foram Solanum, Cyperus, Panicum, Eugenia, Tillandsia, Serjania, Casearia e Polygonum, que juntos reuniram 10,2 por cento do número de espécies. Estes dados, somados aos publicados em 1997, permitiram elevar para 955 espécies, 555 gêneros e 128 famílias, distribuídos entre herbáceas, arbustivas, arbóreas, lianas e epífitas, e em diversas formações ripárias. Panicum maximum, Pennisetum purpureum, Ricinus communis e Urochloa decumbens são consideradas invasoras e sugerimos estudos propondo seu controle.


Assuntos
Biodiversidade , Plantas/classificação , Rios , Brasil
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