Estudo metanalítico sobre a microbiologia da carne bovina moída no Brasil / Meta-analytical study on the microbiology of ground beef in Brazil

RESUMO Objetivou-se avaliar a qualidade microbiológica da carne bovina moída por meio de um estudo metanalítico. Para o estudo metanalítico, utilizou-se como base de dados o Google Scholar Brasil, concentrando-se no período de busca entre outubro de 2020 e junho de 2021. Foram avaliados 108 estudos científicos com as variáveis analisadas referentes a contagens de bactérias mesófilas, bactérias psicrotróficas, coliformes totais, coliformes termotolerantes, Staphylococcus aureus e Salmonella sp. em unidade formadora de colônia por grama de carne (UFC.g-1). Os dados foram submetidos a uma análise descritiva e distribuição normal por histograma de frequência. As contagens de bactérias mesófilas apresentaram uma média de 3,09 UFC.g-1 com coeficiente de variação de 68,53%. As bactérias psicrotróficas apresentaram 27,27% dos dados levantados próximos a 5,60 UFC.g-1. Com relação aos coliformes termotolerantes, 40% dos dados levantados estavam com contagens entre 0,90 e 40% em 3,10 UFC.g-1. Oito estudos apresentaram efeitos (P < 0,001) sobre a presença se Salmonella sp. na carne moída, sendo este estudo metanalítico classificado como heterogêneo (Chi2 = 80,39; P < 0,001) e com inconsistência alta (I2 = 81%). A metanálise constatou baixa contagem de bactérias mesófilas e Staphylococcus aureus em pesquisas brasileiras que abordassem a qualidade microbiológica da carne moída bovina. Estudos metanalíticos como o proposto são necessários para identificar os problemas relacionados à transmissão de doenças em alimentos. Observou-se que, nos achados brasileiros, Staphylococcus aureus e mesófilos foram encontrados em menor quantidade, com maior presença de Samonella sp.

ABSTRACT This paper evaluates the microbiological quality of ground beef through a meta-analytic study using Google Scholar Brazil database, with a focus on the search period between October 2020 and June 2021. A total of 108 scientific studies were evaluated with the analyzed variables, referring to the counts of mesophilic bacteria, psychrotrophic bacteria, total coliforms, thermotolerant coliforms, Staphylococcus aureus and Salmonella sp. In colony forming unit per gram of meat (CFU.g-1). Data were subjected to descriptive analysis and normal distribution by frequency histogram. The counts of mesophilic bacteria presented an average of 3.09 CFU.g-1, with a coefficient of variation of68.53%. Psychrotrophic bacteria represented 27.27% of the data collected, close to 5.60 CFU.g-1. Regarding thermotolerant coliforms, 40% of the data collected had counts between 0.90 and 40% at 3.10 CFU.g-1. Eight studies showed effects (p < 0.001) on the presence of Salmonella sp. in ground beef. This meta-analytic study was classified as heterogeneous (Chi2 = 80.39; p < 0.001) and with high inconsistency (P = 81%). Besides, the meta-analysis allowed identifying low counts of mesophilic bacteria and Staphylococcus aureus in Brazilian studies addressing the microbiological quality of ground beef.

PAS-1, a protein from Ascaris suum, modulates allergic inflammationvia IL-10 and IFN-c, but not IL-12

Helminths and their products have a profound immunomodulatory effect upon the inductive and effectorphases of inflammatory responses, including allergy. We have demonstrated that PAS-1, a protein isolatedfrom Ascaris suum worms, has an inhibitory effect on lung allergic inflammation due to its abilityto down-regulate eosinophilic inflammation, Th2 cytokine release and IgE antibody production. Here,we investigated the role of IL-12, IFN-c and IL-10 in the PAS-1-induced inhibitory mechanism using amurine model of asthma. Wild type C57BL/6, IL-12 / , IFN-c / and IL-10 / mice were immunized withPAS-1 and/or OVA and challenged with the same antigens intranasally. The suppressive effect of PAS-1was demonstrated on the cellular influx into airways, with reduction of eosinophil number and eosinophilperoxidase activity in OVA + PAS-1-immunized wild type mice. This effect well correlated with a significantreduction in the levels of IL-4, IL-5, IL-13 and eotaxin in BAL fluid. Levels of IgE and IgG1antibodies were also impaired in serum from these mice. The inhibitory activity of PAS-1 was alsoobserved in IL-12 / mice, but not in IFN-c / and IL-10 / animals. These data show that IFN-c andIL-10, but not IL-12, play an important role in the PAS-1 modulatory effect.

Early stages ofAscaris suuminduce airway inflammation andhyperreactivity in a mouse model

The inflammatory and functional changes that occur in murinelung after infection with 2500 infectiveAscaris suumeggswere studied in this work. A sequential influx of neutrophils,mononuclear cells and eosinophils occurred into airwaysconcomitantly with migration of larvae from liver to thelungs. Histological analysis of the lung showed a severe intraalveolarhaemorrhage at the peak of larval migration (day 8)and the most intense inflammatory cell infiltrate on day 14.AscarisL3 were found in alveolar spaces and inside bronchioleson day 8. The number of eosinophils was elevated inthe blood on days 8 and 14. The peak of eosinophil influx intothe lung was at day 14, as indicated by the high levels of eosinophilperoxidase activity, followed by their migration into theairways. The antibody response against egg and larval antigensconsisted mainly of IgG1 and IgM, and also of IgE andanaphylactic IgG1, that cross-reacted with adult worm antigens.Total IgE levels were substantially elevated during theinfection. Measurement of lung mechanical parametersshowed airway hyperreactivity in infected mice. In conclusion,the murine model ofA. suuminfection mimics the Th2-induced parameters observed in pigs and humans and can beused to analyse the immunoregulatory properties of thishelminth.