The cry2Aa and cry2Ab genes from a Brazilian Bacillus thuringiensis strain were introduced into the genome of the baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) in order to evaluate the heterologous proteins expression in insect cells and their toxicity to different insects. The recombinant viruses (vAcCry2Aa and vSynCry2Ab) were amplified in Trichoplusia ni (BTI-Tn5B1-4) cells and used to infect Spodoptera frugiperda larvae. Total extracts from S. frugiperda infected with the recombinant viruses were analysed by SDS-PAGE, which detected the presence of polypeptides around 65 kDa. Cuboid-shaped protein crystals were observed in insect extracts by light and scanning electron microscopy. Bioassays, using the heterologous proteins showed toxicity against second instar A. gemmatalis larvae (Cry2Aa) with a LC 50 of 1.03 lg/ml and second instar S. frugiperda larvae (Cry2Ab) with a LC 50 of 3.45 lg/ml. No toxic activity was detected for Aedes aegypti and Culex quinquenfaciatus.

Food Safety is an important topic for public health and international trade in food. Residues of veterinary drugs and environmental contaminants in animal products can cause diseases and acute toxicity in organisms exposed to these substances. This study evaluated official monitoring data of veterinary drug residues from the Brazilian Ministry of Agriculture, Livestock and Supply in tissues of poultry and swine in the period between 2002 and 2014 to check for hidden patterns in the occurrence of six common drugs (Closantel, Diclazuril, Nicarbazin, Sulfaquinoxaline, Doxycycline and Sulfamethazinein). The analysis of data was performed by using two machine learning methods: decision tree and neural networks, in addition to visual evaluation through graphs and maps. Contamination rates were low, varying from 0 to 0.66%. A spatial distribution pattern of detections of substances by region was identified, but no pattern of temporal distribution was observed. Nevertless, regressions showed an increase in levels when these substances were detected, so monitoring should continue. However, the results show that the products monitored during the study period presented a low risk to public health.

Resumo A Segurança Alimentar é um tema importante para a saúde pública e o comércio internacional de alimentos. Resíduos de medicamentos veterinários e contaminantes ambientais em produtos de origem animal podem causar doenças e toxicidade aguda em organismos expostos a essas substâncias. Este estudo avaliou dados oficiais de monitoramento de resíduos de medicamentos veterinários do Ministério da Agricultura, Pecuária e Abastecimento em tecidos de aves e suínos no período de 2002 a 2014 para verificar padrões ocultos na ocorrência de seis medicamentos comuns (Closantel, Diclazuril, Nicarbazina, Sulfaquinoxalina, Doxiciclina e Sulfametazina). A análise dos dados foi realizada por meio de dois métodos de aprendizado de máquina: árvore de decisão e redes neurais, além da avaliação visual por meio de gráficos e mapas. As taxas de contaminação foram baixas, variando de 0 a 0,66%. Foi identificado um padrão de distribuição espacial das detecções de substâncias por região, mas nenhum padrão de distribuição temporal foi observado. No entanto, as regressões mostraram um aumento nos níveis quando essas substâncias foram detectadas, portanto, o monitoramento deve continuar. No entanto, os resultados mostram que os produtos monitorados durante o período do estudo apresentaram baixo risco à saúde pública.