Universidade Estadual de Londrina

About: Universidade Estadual de Londrina is a education organization based out in Londrina, Brazil. It is known for research contribution in the topics: Population & Toxoplasma gondii. The organization has 13052 authors who have published 19291 publications receiving 212123 citations.

The citrus flavanone naringenin impairs dengue virus replication in human cells.

Abstract: Dengue is one of the most significant health problems in tropical and sub-tropical regions throughout the world. Nearly 390 million cases are reported each year. Although a vaccine was recently approved in certain countries, an anti-dengue virus drug is still needed. Fruits and vegetables may be sources of compounds with medicinal properties, such as flavonoids. This study demonstrates the anti-dengue virus activity of the citrus flavanone naringenin, a class of flavonoid. Naringenin prevented infection with four dengue virus serotypes in Huh7.5 cells. Additionally, experiments employing subgenomic RepDV-1 and RepDV-3 replicon systems confirmed the ability of naringenin to inhibit dengue virus replication. Antiviral activity was observed even when naringenin was used to treat Huh7.5 cells 24 h after dengue virus exposure. Finally, naringenin anti-dengue virus activity was demonstrated in primary human monocytes infected with dengue virus sertoype-4, supporting the potential use of naringenin to control dengue virus replication. In conclusion, naringenin is a suitable candidate molecule for the development of specific dengue virus treatments.

Validation of the Brazilian version of the 2007 Youth Risk Behavior Survey.

Abstract: OBJETIVO: Validar as propriedades psicometricas da versao brasileira do questionario Youth Risk Behavior Survey (YRBS), versao 2007. METODOS: Foram realizadas traducao para o portugues da versao original do YRBS2007 e retrotraducao para o ingles. As versoes do questionario foram analisadas por comite de juizes. O comite utilizou como criterio de analise as equivalencias semântica, idiomatica, cultural e conceitual. Para identificacao das propriedades psicometricas, a versao final do questionario YRBS2007 traduzida foi administrada em duas ocasioes com intervalo de duas semanas em amostra de 873 estudantes de ambos os sexos, do ensino medio, em Londrina, PR, em 2007. A confiabilidade teste-reteste foi analisada pelo calculo do indice de concordância Kappa e da taxa de prevalencia de cada comportamento de risco nas replicas de aplicacao. Teste de qui-quadrado foi empregado para identificar diferencas estatisticas entre a primeira e a segunda aplicacoes do questionario. RESULTADOS: Apos discretas modificacoes apontadas nos processos de traducao, o comite de juizes considerou que a versao para o idioma portugues do YRBS2007 apresentou equivalencias semântica, idiomatica, cultural e conceitual. Diferencas significativas entre as taxas de prevalencias de ambas as aplicacoes foram observadas em 23,4% dos itens. A identificacao de 91% dos itens com indice de concordância Kappa entre moderado a substancial e valor medio desse indice de 68,6% indicou a qualidade das propriedades psicometricas do YRBS2007 traduzido para o idioma portugues. CONCLUSOES: A traducao, a adaptacao transcultural e as qualidades psicometricas do questionario YRBS2007 foram satisfatorias, o que viabiliza sua aplicacao em estudos epidemiologicos no Brasil.

The natural occurrence of fumonisins in Brazilian corn kernels

Abstract: Since animal intoxication related to corn-based feed is frequently observed in the State of Parana, Brazil, natural contamination by fumonisins in 48 corn samples (39 from the State of Parana, and 9 from the Brazilian tropical states, Mato Grosso do Sul and Goias) harvested in 1990-1991 was investigated, along with fungal flora. The total mould count ranged from 6.3 x 10(2) to 5.5 x 10(7) cfu/g, and Fusarium moniliforme and Aspergillus species belonging to section Flavi were detected in 41 and 33 samples, respectively. Regarding the samples from the State of Parana, F. moniliforme was present in 33 samples at a count of 1.0 x 10(2) to 1.6 x 10(7) cfu/g and Aspergillus spp. in section Flavi in 27 samples at 1.0 x 10(2) to 1.0 x 10(6) cfu/g. HPLC analysis of fumonisins in the corn showed that fumonisins B1 (FB1) and B2 (FB2) were positive for 97.4% and 94.8% of samples respectively. All the corn from North Parana was positive for fumonisins, with average FB1 levels of 4.79 micrograms/g and average FB2 levels of 3.95 micrograms/g: the Central-West region had average levels of 3.30 and 2.52 micrograms/g, and the Central-East had average of 3.25 and 2.34 micrograms/g, respectively. Except for one negative sample all the corn samples from the Central Region were positive for fumonisins, averaging FB1 levels being 5.45 micrograms/g and FB2 levels being 5.09 micrograms/g. Out of eight samples from the tropical state of Mato Grosso do Sul, F. moniliforme was detected in seven and Aspergillus spp. in section Flavi in five samples with average FB1 levels of 10.59 micrograms/g and average for FB2 levels of 10.31 micrograms/g. The samples from Goias were also contaminated with these two fungi, with the FB1 contamination being 5.83 and the FB2 contamination 3.62 micrograms/g.