Lyra T.M.D.P.,Confederacao Nacional de Agricultura e Pecuaria Do Brazil |
Freitas T.R.P.,Laboratorio Nacional Agropecuario
Semina:Ciencias Agrarias | Year: 2015
After the first African swine fever (ASF) outbreak occurred in Brazil in 1978, an official laboratory for ASF diagnosis (ASFDL) was established. The current work reviews the efforts of the laboratory team to define an ASF diagnosis during the emergency phase of the ASF Eradication Program. From June to December 1978, 3,803 samples of pig tissue, blood and serum were analyzed. ASFDL first isolated the ASF virus (ASFV) from pig tissue samples from the Teresópolis municipality in the Brazilian state of Rio de Janeiro. During the first two months, ASFV was isolated from 130 of 320 (40.62%) pig samples analyzed by haemadsorption (HAD), indicating that the outbreak had reached 96 of 214 municipalities surveyed throughout the country in that period. The distribution of positive ASFV samples indicated the potential route of virus dispersal. Because of the rapidity of the actions implemented against ASF, the number of ASFV positive samples decreased from 48.36% in June to 33.53% in July, and then to 0% in August 1978. In parallel, ASFV antibody detection increased from 17.89% in June to 52.04% in August 1978. In the state of Paraná, a comparison of ASFV isolates with descriptions of the disease, and a rapid decrease in mortality rates suggested the occurrence of a low or moderate virulence ASFV strain. Establishment of ASFDL was crucial for the program, which eradicated ASFV from the country within six years of the first outbreak. Advances in cellular and molecular biology corroborated pioneer studies regarding ASFV virulence, and have highlighted the importance of establishing and maintaining secure measures to prevent ASFV reintroduction to the country. Information on virulence heterogeneity in ASFV populations during outbreaks provided a paramount tool for the adoption of eradication best practices.
Hoff R.B.,Laboratorio Nacional Agropecuario |
Hoff R.B.,Federal University of Rio Grande do Sul |
Meneghini L.,Laboratorio Nacional Agropecuario |
Pizzolato T.M.,Federal University of Rio Grande do Sul |
And 4 more authors.
Analytical Chemistry | Year: 2014
Four previously unreported metabolism products of sulfaquinoxaline (SQX), a widely used veterinary medicine, were isolated and analyzed using liquid chromatography coupled to high-resolution Orbitrap mass spectrometry. Metabolites were structurally elucidated, and a fragmentation pathway was proposed. The combination of high-resolution MS2 spectra, linear ion trap MS2, in-source collision-induced dissociation (CID) fragmentation, and photolysis were used to analyze SQX and its metabolites. All metabolism products identified showed a similar fragmentation pattern to that of the original drug. Differential product ions were produced at m/z 162 and 253 which contain the radical moiety with more 16 Da units than sulfaquinoxaline. This occurs by a hydroxyl attachment to the quinoxaline moiety. With the exception of two low-intensity compounds, all the mass errors were below 5.0 ppm. The distribution of these metabolites in some animal species are also presented and discussed. © 2014 American Chemical Society.
Folloni S.,European Commission - Joint Research Center Ispra |
Kagkli D.-M.,European Commission - Joint Research Center Ispra |
Rajcevic B.,European Commission - Joint Research Center Ispra |
Guimaraes N.C.C.,Laboratorio Nacional Agropecuario |
And 4 more authors.
Molecular Ecology Resources | Year: 2012
The cultivation of genetically modified (GM) crops has raised numerous concerns in the European Union and other parts of the world about their environmental and economic impact. Especially outcrossing of genetically modified organisms (GMO) was from the beginning a critical issue as airborne pollen has been considered an important way of GMO dispersal. Here, we investigate the use of airborne pollen sampling combined with microscopic analysis and molecular PCR analysis as an approach to monitor GM maize cultivations in a specific area. Field trial experiments in the European Union and South America demonstrated the applicability of the approach under different climate conditions, in rural and semi-urban environment, even at very low levels of airborne pollen. The study documents in detail the sampling of GM pollen, sample DNA extraction and real-time PCR analysis. Our results suggest that this 'GM pollen monitoring by bioaerosol sampling and PCR screening' approach might represent an useful aid in the surveillance of GM-free areas, centres of origin and natural reserves. © 2012 Blackwell Publishing Ltd.
Kaiser S.,Federal University of Rio Grande do Sul |
Verza S.G.,Federal University of Rio Grande do Sul |
Moraes R.C.,Federal University of Rio Grande do Sul |
De Resende P.E.,Federal University of Rio Grande do Sul |
And 3 more authors.
Quimica Nova | Year: 2013
Cat's claw oxindole alkaloids are prone to isomerization in aqueous solution. However, studies on their behavior in extraction processes are scarce. This paper addressed the issue by considering five commonly used extraction processes. Unlike dynamic maceration (DM) and ultrasound-assisted extraction, substantial isomerization was induced by static maceration, turbo-extraction and reflux extraction. After heating under reflux in DM, the kinetic order of isomerization was established and equations were fitted successfully using a four-parameter Weibull model (R2 > 0.999). Different isomerization rates and equilibrium constants were verified, revealing a possible matrix effect on alkaloid isomerization.
Dorneles E.M.S.,Federal University of Minas Gerais |
de Faria A.P.P.,Federal University of Minas Gerais |
de Faria A.P.P.,University of Brasilia |
Pauletti R.B.,Federal University of Minas Gerais |
And 5 more authors.
Vaccine | Year: 2013
The aims of the present study were (i) to assess the in vitro genetic stability of S19 and RB51 Brucella abortus vaccines strains and (ii) to evaluate the ability of multiple- locus variable-number tandem repeat (VNTR) analysis (MLVA) as a tool to be used in the quality control of live vaccines against brucellosis. Sixty-three batches of commercial S19 (n= 53) and RB51 (n= 10) vaccines, produced between 2006 and 2009, were used in this study. S19 and RB51 vaccines were obtained from, respectively, seven and two different manufacturers. Ten in vitro serial passages were performed on reference strains and on selected batches of commercial vaccines. All batches, reference strains and strains of serial passages were typed by the MLVA16. The results demonstrated that B. abortus S19 and RB51 vaccine strains are genetically stable and very homogeneous in their respective groups. Anyway, batches of S19 from one manufacturer and batches of RB51 from another presented genotypes distincts from the reference vaccine strains. In both cases, differences were found on locus Bruce07, which had addition of one repeat unit in the case of S19 batches and the deletion of one repeat unit in the case of RB51 batches. In summary, MLVA16 proved to be a molecular tool capable of discriminating small genomic variations and should be included in in vitro official tests. © 2013.
PubMed | Laboratorio Nacional Agropecuario, Federal University of Minas Gerais and Federal University of Lavras
Type: | Journal: Acta tropica | Year: 2016
The aims of the present study were to genotype Brucella abortus strains isolated from cattle in Brazil between 2009 and 2013, and to analyze their distribution to support the Programa Nacional de Controle e Erradicao de Brucelose e Tuberculose (PNCEBT) (National Brucellosis and Tuberculosis Control and Eradication Program). One hundred forty B. abortus strains isolated from cattle in Brazil between 2009 and 2013 were genotyped using a set of 18 variable number of tandem repeats (VNTR) (MLVA16+HOOF-Print 3 and 4). The multiple locus VNTR analysis (MLVA) composed by eight markers (MLVA8) revealed eight different genotypes among B. abortus strains, including five previously described and three new ones. Analysis of the MLVA16 loci revealed fifty-eight distinct genotypes, from which three were identical, thirty-eight were considered very close, and seventeen were considered distant compared to those previously described and deposited in MLVAbank. Analysis of the HOOF-Prints 3 and 4 revealed the larger number of different alleles among all VNTR assessed, exhibiting maximum resolution when associated with MLVA16 markers. This study also provides insights on the genotypes of B. abortus circulating in Brazil, which certainly contribute for the better understanding of the epidemiology and control of bovine brucellosis in the country. Moreover, our data showed a high genetic diversity among the B. abortus strains isolated between 2009 and 2013, and a close relationship among these strains and Brazilian B. abortus deposited by MLVAbank.
PubMed | Federal University of Santa Catarina and Laboratorio Nacional Agropecuario
Type: Journal Article | Journal: Journal of the science of food and agriculture | Year: 2016
Pangasius is a fish produced on a large scale in Vietnam and exported to many countries. Since river contamination from human activities can affect the safety of this food, fish consumption can cause exposure to potentially toxic elements for humans. The aim of this study, therefore, was to assess arsenic, cadmium, lead, copper and chromium contents by atomic absorption spectrometry in Pangasius fillet produced in the provinces of Dong Thap and Can Tho (Vietnam) and exported to Brazil.The limits of detection were: arsenic 0.5443gkg(-1) , cadmium 0.0040mgkg(-1) , chromium 0.0004mgkg(-1) , copper 0.0037mgkg(-1) and lead 0.0284mgkg(-1) . Analysis of 20 samples showed results below the limit of detection for arsenic, chromium and lead, while copper average concentration was 0.0234mgkg(-1) . Cadmium average concentration was 0.0547mgkg(-1) , with no significant difference between the two regions studied.The samples of Pangasius had no detectable concentrations of arsenic, chromium, copper and lead, and do not represent a hazard to public health. However, cadmium analysis revealed non-compliant samples, demonstrating the importance of monitoring the quality of imported Pangasius fish. 2015 Society of Chemical Industry.
PubMed | Federal University of Minas Gerais and Laboratorio Nacional Agropecuario
Type: Comparative Study | Journal: Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology] | Year: 2014
The aims of this study were to standard and optimize a qPCR protocol with FAM-BHQ1 probe, and to compare its sensitivity against TaqMan qPCR and PCR methods to diagnose shrimp WSD. The FAM-BHQ1 qPCR presented higher clinical sensitivity and showed to be a robust alternative to detect WSSV in clinical samples.
PubMed | Federal University of Rio Grande do Sul and Laboratorio Nacional Agropecuario
Type: Journal Article | Journal: International journal of environmental research and public health | Year: 2014
A simple and inexpensive method based on solvent extraction followed by low temperature clean-up was applied for determination of seven pyrethroids residues in bovine raw milk using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) and gas chromatography with electron-capture detector (GC-ECD). Sample extraction procedure was established through the evaluation of seven different extraction protocols, evaluated in terms of analyte recovery and cleanup efficiency. Sample preparation optimization was based on Doehlert design using fifteen runs with three different variables. Response surface methodologies and polynomial analysis were used to define the best extraction conditions. Method validation was carried out based on SANCO guide parameters and assessed by multivariate analysis. Method performance was considered satisfactory since mean recoveries were between 87% and 101% for three distinct concentrations. Accuracy and precision were lower than 20%, and led to no significant differences (p < 0.05) between results obtained by GC-ECD and GC-MS/MS techniques. The method has been applied to routine analysis for determination of pyrethroid residues in bovine raw milk in the Brazilian National Residue Control Plan since 2013, in which a total of 50 samples were analyzed.
PubMed | Federal University of Santa Catarina and Laboratorio Nacional Agropecuario
Type: | Journal: Talanta | Year: 2015
In this work, a simplified extraction and short time of analysis method for the simultaneous determination of natamycin, nisin and sorbic acid in cheeses and cream by reverse phase liquid chromatography-electrospray-tandem mass spectrometry was developed. Full validation was performed according to the Commission Decision 2002/657/EC criteria and method applicability was checked on several samples, aiming to inspect their compliance with regulatory limits. The method was linear in the concentration ranges of 0-10mg kg(-1) (natamycin), 0-25mg kg(-1) (nisin) and 0 20mg kg(-1) (sorbic acid). Samples of the three most consumed types of cheese (fresh, pasta filata and ripened) in Brazil and cream (ultra high temperature and pasteurized, 20-30% fat content) were assessed. A surprising rate of non-compliance was observed, especially among ripened grated cheeses, since 80% of samples were above the maximum limit for sorbic acid with an average concentration of 2766.310.8mg kg(-1). Moreover, a major non-compliance for the cream samples was observed. The proposed method can be applied as an efficient tool for the inspection of preservatives in cheeses and cream.