Mass spectrometry parameters optimization for the 46 multiclass pesticides determination in strawberries with gas chromatography ion-trap tandem mass spectrometry

Multiclass analysis method was optimized in order to analyze pesticides traces by gas chromatography with ion-trap and tandem mass spectrometry (GC-MS/MS). The influence of some analytical parameters on pesticide signal response was explored. Five ion trap mass spectrometry (IT-MS) operating parameters, including isolation time (IT), excitation voltage (EV), excitation time (ET),maximum excitation energy or “q” value (q), and isolationmass window (IMW) were numerically tested in order to maximize the instrument analytical signal response. For this, multiple linear regression was used in data analysis to evaluate the influence of the five parameters on the analytical response in the ion trap mass spectrometer and to predict its response. The assessment of the five parameters based on the regression equations substantially increased the sensitivity of IT-MS/MS in the MS/MS mode. The results obtained show that for most of the pesticides, these parameters have a strong influence on both signal response and detection limit.Using the optimized method, a multiclass pesticide analysis was performed for 46 pesticides in a strawberry matrix. Levels higher than the limit established for strawberries by the European Union were found in some samples

Evaluation of antifungal activity of essential oils against potentially mycotoxigenic Aspergillus flavus and Aspergillus parasiticus

The antifungal activity of essential oils of fennel (Foeniculum vulgare Mill., Apiaceae), ginger (Zingiber officinale Roscoe, Zingiberaceae), mint (Mentha piperita L., Lamiaceae) and thyme (Thymus vulgaris L., Lamiaceae) was evaluated against mycotoxin producers Aspergillus flavus and A. parasiticus. High Resolution Gas Chromatography was applied to analyze chemical constituents of essential oils. The effect of different concentrations of essential oils was determined by solid medium diffusion assay. Mycelial growth and sporulation were determined for each essential oil at the concentrations established by solid medium diffusion assay. At the fifth, seventh and ninth days the mycelial diameter (Ø mm) and spore production were also determined. FUN-1 staining was performed to assess cell viability after broth macrodilution assay. Trans-anethole, zingiberene, menthol and thymol are the major component of essential oils of fennel, ginger, mint and thyme, respectively. The effective concentrations for fennel, ginger, mint and thyme were 50, 80, 50 and 50% (oil/DMSO; v/v), respectively. The four essential oils analysed in this study showed antifungal effect. Additionally, FUN-1 staining showed to be a suitable method to evaluate cell viability of potential mycotoxigenic fungi A. flavus and A. parasiticus after treatment with essential oils.The authors are grateful to the colleagues from Laboratory of EPAMIG and Microbiology DEB/UFLA and the Micoteca da Universidade do Minho, Center for Biological Engineering, UMINHO for their support to perform this work. A special aknowledgment is also due to the FAPEMIG and MUM-UMINHO for the financial support of bench work and to CAPES for granting the first author with a PhD scholarship

Filamentous fungi in drinking water tanks of a water supply system in Recife-PE, Brazil

Drinking water reservoirs are widely used in various building constructions in Brazil for as a source of potable water for users. However, they are susceptible to the growth of microorganisms such as fungi. From these, several negative factors may ensue, namely, unpleasant odors and flavours, pigments, biofilm formation and mycotoxins. This is caused fungal resistance to treatment and disinfection. Brazilian law and those of other countries offer no encouragement for the research of the species of fungi that cause these problems. There are no legal limits as to the presence in drinking water. This study assesses the occurrence of filamentous fungi in drinking water reservoirs connected to the Alto do Céu distribution system located in Recife, Pernambuco, Brazil. Four monthly collections were carried out, in triplicate, at two fixed points in the network, at the same treatment area, and another 2.0 km away from this site. For water physicochemical characterization at the time of collection, pH, temperature and free residual chlorine were analyzed. Filamentous fungi were quantified by filtration through cellulose nitrate membrane with a 0.45 μm porosity. All strains were grown in Petri dishes containing Peptone Glucose, Rose Bengal Agar (PGRBA) and were incubated at 30°C for 48h. Fungal occurrence was quantified as colony forming units (CFU) per litre. Twenty-four samples were analyzed, and these accounted for 807 CFU. Considering the potential for water spreading diseases, and the high toxicity of fungi into account it is intended that this work may prompt the creation of acceptable parameters as to the presence of fungi in drinking water networks

Filamentous fungi in biofilms of water tanks in a supply system in Recife-PE, Brazil

Fungi cause detrimental organoleptic effects in water, and their presence may facilitate the occurrence of infections, allergic reactions and harmful effects from mycotoxins. Despite the lack of knowledge on the biological structure of filamentous fungi in biofilms, it is known that they can contribute with bacteria, yeasts, protozoa and viruses. Hence, this study analyzed, in situ, filamentous fungi in biofilms found in drinking water reservoirs of the distribution network in Alto do Céu, Recife, Pernambuco, Brazil. Biofilms were collected, in triplicate from samplers consisting of a polyethylene plate (4.0cm x 1.5cm) established in drinking water reservoirs. Four monthly collections were carried out between August and November 2011 at two fixed points. Polyethylene samplers were taken to the laboratory and washed with sterile water and transferred to Petri dishes containing medium Peptone, Glucose, Rose Bengal Agar (PGRBA). The plates were incubated at 30°C for 48h. The occurrence of fungi was reported as CFU/L. Fifty three colony forming units of fungi were quantified. For water physicochemical characterization at the time of collection, pH, temperature and free residual chlorine were analyzed. For detection of biofilms, a combination of two fluorescent techniques was used: (A) Fluorescent “in situ” hybridization (FISH) using a rDNA universal probe EUK516 (ACCAGACTTGCCCTCC 5’-3’, MWG Biotech, Ebersberg, Germany) labeled with cyanine Cy3 at the 5’ end and (B) Calcofluor White M2R (CW). After FISH and CW, the samples were observed under an epifluorescent microscope. Fungal filaments which formed biofilms in the distribution network were observed establishing biofilm formation. These results confirm the presence and relevance of filamentous fungi in structuring biofilms

O marcapasso definitivo como alternativa terapêutica na doença aterosclerótica coronariana com bloqueio AV total e síncope. Apresentaçao de caso

Homem com 52 anos de idade, portador de diabetes mellitus, hipertensao arterial sistêmica e doença aterosclerótica coronariana. Apresentava episódios de síncope precedidos por angina, durante os quais o eletrocardiograma mostrava ritmo sinusal e bloqueio AV total, com corrente de lesao subepicárdica. A cineangiocoronariografia revelou lesoes ateroscleróticas significativas nas três artérias coronárias. A terapêutica proposta foi a cirurgia de revascularizaçao do miocárdio, recusada pelo paciente. As opçoes farmacológicas foram exploradas sem sucesso. O implante de marca passo definitivo tipo VVI foi realizado como a única e razoável opçao terapêutica. No seguimento de um ano o paciente nao mais apresentou síncopes

O projecto nacional de educação pelos pares da Fundação Portuguesa “A comunidade contra a sida” em escolas EB2/3 do Porto

O Projecto Nacional de Educação pelos Pares, focado na sexualidade e prevenção do VIH/ SIDA, foi criado pela Fundação Portuguesa “A Comunidade Contra a SIDA” no âmbito do Centro de Aconselhamento e Orientação de Jovens (CAOJ). O processo de aprendizagem, desenvolvido a partir do diagnóstico das necessidades de formação do público-alvo, recorre a metodologias activas que visam educar os adolescentes para uma vivência gratificante da sua sexualidade e prepará-los para assumirem o seu papel de “pares educadores” de colegas mais jovens. Esta educação de pares dirigida a alunos que frequentam o 3º ciclo do Ensino Básico é dinamizada, numa primeira fase, por jovens voluntários universitários organizados em Brigadas Universitárias de Intervenção (BUI) e no Teatro Universitário de Intervenção (TUI). Estes voluntários, com o acompanhamento de professores destacados para o CAOJ, responsáveis pela sua formação pedagógica, desenvolvem o projecto com alunos do 7º ao 9º ano de escolaridade. No terceiro ano de formação, os alunos do 3º ciclo organizados em Brigadas Escolares de Intervenção (BEI) iniciam a sua acção como educadores dos colegas mais novos, geralmente dos 2º e 1º ciclos. Esta comunicação, pretende mostrar a dinâmica deste Projecto desenvolvido em cinco escolas EB2/3 do Porto e discutir, com base em evidências recolhidas junto dos professores, voluntários e alunos envolvidos, alguns resultados obtidos neste ano lectivo

A influência das relações interpessoais no desempenho escolar e motivação

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PESQUISA DE Listeria monocytogenes e Staphylococcus COAGULASE-POSITIVOS EM QUEIJO MUÇARELA FATIADO ADQUIRIDO EM PADARIAS E SUPERMERCADOS DE GOIÂNIA-GO

Introdução e objetivos: Alguns produtos lácteos são considerados de alto risco relativo para transmissão de toxiinfecções alimentares, uma vez que oferecem excelente substrato nutricional para desenvolvimento de diversos micro-organismos patogênicos, como Listeria monocytogenes e Staphylococcus aureus produtor de enterotoxinas. O presente estudo objetivou verificar a presença de L. monocytogenes e Staphylococcus coagulase-positivos em amostras de queijo muçarela fatiado, adquiridas em padarias e supermercados da cidade de Goiânia. Metodologia: Entre outubro de 2014 e janeiro de 2015, 19 amostras do alimento foram analisadas no Laboratório de Controle de Qualidade de Alimentos e Medicamentos da Faculdade de Farmácia, Universidade Federal de Goiás. Para pesquisa de Listeria sp. utilizou-se o protocolo preconizado pelo FDA1, utilizando-se dois meios de enriquecimento seguido de plaqueamento em superfície de ágar seletivo. Os resultados foram confirmados através do kit ApiListeria (bioMérieux). Para identificação presuntiva de Staphylococcus aureus utilizou-se Ágar Baird Parker, conforme recomendação do APHA2, e realizou-se o teste de coagulase. Resultados e discussões: A presença de L. monocytogenes foi confirmada em uma (5,26%) das amostras analisadas e a presença de L. innocua em outra amostra (5,26%). Diversos estudos relatam o isolamento de L. monocytogenes a partir de diferentes tipos de queijos, fatiados ou não3. Não foi possível confirmar a presença de Staphylococcus coagulase-positivos nas amostras de queijo muçarela analisadas, entretanto, detectou-se Staphylococcus coagulase-negativos em 6 (31,6%) das amostras. Apesar de a maioria dos S. aureus produtores de enterotoxinas isolados de alimentos ser produtora de coagulase, estudos indicam que Staphylococcus coagulase-negativos também podem produzir enterotoxinas4. Conclusão: Os resultados do presente estudo evidenciam que o queijo muçarela fatiado pode atuar como veículo para transmissão de bactérias patogênicas para os consumidores