Molecular differentiation of Salmonella Gallinarum and Salmonella Pullorum by RFLP of fliC gene from Brazilian isolates

Although Salmonella Pullorum and Salmonella Gallinarum cause different diseases in poultry, they are very similar. Both are non-motile and present the same somatic antigenic structure. They are differentiated by biochemical tests. Certain atypical strains are very difficult to distinguish. They do not produce the expected results when dulcitol and ornithine descarxboxylase tests are performed. Therefore, additional tests could be helpful. Many studies have chose the part I of the gene that encodes flagellin (fliC) to differentiate serotypes. Most Salmonella strains have two structural genes (fliC and fliB) that encode flagellins. Non-motile strains generally present these structural genes, but are not able to build a functional flagellum. It was demonstrated that enzymatic restriction of the amplified fliC gene using Hinp1I enzyme can differentiate SG from SP. In the present study, this method was adopted to analyze 14 SP and 22 SG strains, including some strains with atypical results in biochemical tests assessing the utilization of dulcitol and ornithine. The results showed that all SG strains were broken by the enzyme, whereas the 14 SP strains were not.

Sensitivity evaluation of a single-step PCR assay using Ehrlichia canis p28 gene as a target and its application in diagnosis of canine ehrlichiosis

O objetivo deste estudo foi aperfeiçoar um ensaio de PCR que amplificasse um fragmento de 843 pares de bases do gene p28 da Ehrlichia canis e compará-lo com outros dois métodos de PCR utilizados para amplificar partes do gene 16S rRNA e dsb do gênero Ehrlichia. Amostras sanguíneas foram colhidas de cães com diagnóstico clínico de erliquiose. A amplificação do gene p28 pela PCR produziu um fragmento de 843pb e esse ensaio permitiu a detecção do DNA de um parasita dentre 1 bilhão de células. Todas as amostras positivas detectadas pela PCR baseada no gene p28 foram também positivas pela nested PCR para detecção do gene 16S rRNA e também pela PCR dsb. Dentre as amostras negativas para a PCR p28, 55,3% foram co-negativas, mas 27,6% foram positivas pela PCR baseada nos genes 16S rRNA e dsb. A PCR p28 parece ser um teste útil para detecção molecular de E. canis, entretanto otimizações na sensibilidade nesta PCR são necessárias, para que esta técnica se torne uma importante alternativa no diagnóstico da erliquiose canina.

Control of Salmonella enterica serovar Enteritidis in laying hens by inactivated Salmonella Enteritidis vaccines

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Detection of anti-Toxoplasma gondii antibodies in experimentally and naturally infected non-human primates by Indirect Fluorescence Assay (IFA) and indirect ELISA

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

An enzyme-linked immunosorbent assay (ELISA) for the detection of IgM antibodies against Leishmania chagasi in dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A nested-PCR assay for detection of Xylella fastidiosa in citrus plants and sharpshooter leafhoppers

Aims: Detection of Xylella fastidiosa in citrus plants and insect vectors.Methods and Results: Chelex 100 resin matrix was successfully standardized allowing a fast DNA extraction of X. fastidiosa. An amplicon of 500 bp was observed in samples of citrus leaf and citrus xylem extract, with and without symptoms of citrus variegated chlorosis, using PCR with a specific primer set indicating the presence of X. fastidiosa. The addition of insoluble acid-washed polyvinylpyrrolidone (PVPP) prior to DNA extraction of insect samples using Chelex 100 resin together with nested-PCR permitted the detection of X. fastidiosa within sharpshooter heads with great sensitivity. It was possible to detect up to two bacteria per reaction. From 250 sharpshooter samples comprising four species (Dilobopterus costalimai, Oncometopia facialis, Bucephalogonia xanthopis and Acrogonia sp.), 87 individuals showed positive results for X. fastidiosa in a nested-PCR assay.Conclusions: the use of Chelex 100 resin allowed a fast and efficient DNA extraction to be used in the detection of X. fastidiosa in citrus plants and insect vectors by PCR and nested-PCR assays, respectively.Significance and Impact of the study: the employment of efficient and sensitive methods to detect X. fastidiosa in citrus plants and insect vectors will greatly assist epidemiological studies.

Genotoxicity and antigenotoxicity assessment of shiitake (Lentinula edodes (Berkeley) Pegler) using the Comet assay

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evaluation of curcumin and cisplatin-induced DNA damage in PC12 cells by the alkaline comet assay

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Antitumoral, mutagenic and (anti)estrogenic activities of tingenone and pristimerin

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação do meio Agar Xilose Lisina Verde Brilhante no isolamento de Salmonella

Ao pesquisar-se a presença de Salmonella a partir de materiais diversos, foram empregados vários meios de cultura e entre eles o meio Agar Xilose Lisina Verde Brilhante, com a finalidade de avaliá-lo em relação a outros meios seletivo-indicadores mais comumente empregados no isolamento desses microrganismos. Os resultados mostraram que o meio Agar Xilose Lisina Verde Brilhante foi inferior aos Agar SS e Agar Verde Brilhante, ligeiramente superior ao Agar EMB e superior ao Agar Sulfito de Bismuto no isolamento de Salmonella. Grande vantagem adicional desse meio é que as colônias de Salmonella apresentam-se facilmente identificáveis.

Assessment of estrogenic, mutagenic and antimutagenic activity of nemorosone

Currently, a wide range of research involving natural products is focused on the discovery of new drugs in many different therapeutic areas. A great number of the synthetic compounds on the market were derived from natural products, especially plants. Nemorosone is the major constituent of the floral resin of Clusia rosea Jacq., Clusiaceae, and in Cuban propolis. In vitro studies have shown cytotoxic activity in this substance against various tumor cell lines, including those resistant to various cytotoxic drugs, whereas it has low cytotoxicity to non-tumoral cells. Therefore, in order to characterize the biological activity of nemorosone, a substance with potential antitumor activity, and in view of preclinical testing of the toxicity of drug candidate compounds, the main aim of this study was to determine the mutagenic and antimutagenic activity of nemorosone by the Ames test, using the strains TA97a, TA98, TA100 and TA102 of Salmonella typhimurium. Secondly, to characterize the estrogenic activity in an experimental recombinant yeast model (Recombinant Yeast Assay) mutagenic activity was observed at in any of the concentrations in any of the test strains. To evaluate the antimutagenic potential, direct and indirect mutagenic agents were used: 4 nitro-o-phenylenediamine (NPD), mitomycin C (MMC) and aflatoxin B1 (AFL). Nemorosone showed moderate antimutagenic activity (inhibition level 31%), in strain TA100 in the presence of AFL, and strong antimutagenic activity in TA102 against MMC (inhibition level 53%). Estrogenic activity was observed, with an EEq of 0.41±0.16 nM at various tested concentrations.

Mutagenicity induced by the hydroalcoholic extract of the medicinal plant Plathymenia reticulata Benth

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Assessment of DNA damage induced by extracts, fractions and isolated compounds of Davilla nitida and Davilla elliptica (Dilleniaceae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In vivo assessment of DNA damage and protective effects of extracts from Miconia species using the comet assay and micronucleus test

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Rapid detection of resistance to pyrazinamide in Mycobacterium tuberculosis using the resazurin microtitre assay

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)