Editorial: Bacteriophages in the fight against foodborne pathogens

Editorial on the Research Topic Bacteriophages in the fight against foodborne pathogens(undefined)info:eu-repo/semantics/publishedVersio

Novel Same-Day method for viable Salmonella Enteritidis detection in chicken meat combining phage amplification and LAMP

Salmonella enterica is a major foodborne pathogen worldwide. Poultry products, especially eggs and meat, are the main responsible for human salmonellosis cases. Culture-based methods require at least 3 days to detect Salmonella positive samples. To facilitate food chain processes and provide a rapid response to food outbreaks, a simple and rapid detection method is necessary. For this purpose, nucleic acid amplification-based techniques are a potential solution. Loop-Mediated isothermal AMPlification (LAMP) has emerged as an alternative to qPCR due to the simple equipment necessary to perform the analysis while allowing the detection of living cells when combined with bacteriophages. The aim of this work was to develop a same-day protocol based in the combination of LAMP and a Salmonella phage (vB-SenS_PVP-SE2) to detect viable Salmonella Enteritidis cells in chicken meat. Specific LAMP primers were designed to target the capsid and endolysin genes of Salmonella phage vB-SenS_PVP-SE2. Two different detection strategies were developed: real-time fluorescence; and colorimetric (naked-eye detection). The LAMP method developed could detect down to 0.2 fg/L of pure phage DNA and concentrations of viral particles in buffered peptone water (BPW) of 10 pfu/mL. After optimization in spiked chicken samples, a 3 h sample pre-enrichment diluted 1/10 in BPW before phage addition to the samples followed by a co-incubation (with phage) of 4 h was established. The proposed method could determine the presence of S. Enteritidis in less than 8 h including sample processing, DNA isolation and LAMP analysis with a LOD of 1.5 cfu/25g and a LOD of 6.6 cfu/25g, both by fluorescence and naked-eye observation. The results were in close concordance with the reference method for Salmonella spp., the ISO 6579-1:2017. The described method represents a promising alternative for the rapid detection of Salmonella in the food chain.info:eu-repo/semantics/publishedVersio

Estrutura econômica e integração produtiva : uma análise de insumo-produto para a região metropolitana de Curitiba

Orientador: Prof. Dr. Alexandre Alves PorsseDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Sociais Aplicadas, Programa de Pós-Graduação em Desenvolvimento Econômico. Defesa : Curitiba, 01/03/2019Inclui referências: p. 65-68Resumo: O objetivo desta dissertação é analisar a estrutura econômica da Região Metropolitana de Curitiba (RMC) e suas interações internas utilizando a modelagem insumo-produto a partir da estimação da MIP. Essa análise é realizada com base nos principais indicadores estruturais da abordagem insumo-produto: multiplicadores da produção, índices de ligação e decomposição regional do multiplicador da produção. O estudo foi realizado em duas etapas principais. A primeira foi de calibragem, em que a matriz insumo-produto foi construída a partir da matriz de usos e recursos do IBGE, para o ano de 2010, adotando procedimentos inspirados no método Interregional Input-Output Adjustment System desenvolvido por Haddad et al. (2017). A segunda etapa foi analítica, ou seja, alguns indicadores estruturais usuais na abordagem insumoproduto foram calculados e analisados. O modelo insumo-produto utilizado foi implementado com 20 regiões (18 cidades que compõem o aglomerado de caráter metropolitano de Curitiba - RMC, o Restante do Paraná e o Restante do Brasil). A matriz tem uma abertura setorial composta por 23 setores produtivos. Os resultados evidenciam que as políticas de desenvolvimento industrial no Paraná modificaram a estrutura econômica da RMC, resultando em uma estrutura mais diversificada e complexa do que aquela observada nos anos 70 e 80, que era especializada em setores tradicionais como produtos alimentares e madeira. Entretanto, os setores-chaves ainda são restritos na RMC, abrangendo a Indústria Petroquímica, a Metalurgia e a Madeira e Celulose, que predominantemente se localizam nas cidades de Araucária, São José dos Pinhais e Curitiba. Por último, a análise de decomposição regional mostra que a maioria dos setores industriais na RMC possuem elevado grau de vazamento regional do multiplicador da produção. Palavras-chave: Matriz insumo-produto regional. Região Metropolitana de Curitiba. Indicadores Estruturais. Modelo Interregional Input-Output Adjustment System -IIOAS.Abstract: The objective of this dissertation is to analyze the economic structure of the Metropolitan Region of Curitiba (MRC) and its internal interactions using input-output modeling from the estimation of MIP. This analysis is based on the main structural indicators of the input-output approach: production multipliers, linkage indices, and regional decomposition of the production multiplier. The study was conducted in two main stages. The first one was calibration, in which the input-output matrix was constructed from the matrix of uses and resources of IBGE for the year of 2010, adopting procedures inspired by the Interregional Input-Output Adjustment System developed by Haddad et al. (2017). The second stage was analytical, that is, some usual structural indicators in the input-output approach were calculated and analyzed. The inputoutput model was implemented with 20 regions (18 cities that make up the metropolitan cluster of Curitiba - RMC, the Rest of Paraná and the Rest of Brazil). The matrix has a sectorial opening composed of 23 productive sectors. The results show that industrial development policies in Paraná have modified the economic structure of the MRC, resulting in a more diversified and complex structure than that observed in the 1970s and 1980s, which specialized in traditional sectors such as food and wood. However, key sectors are still restricted in the MRC, covering the Petrochemical Industry, Metallurgy and Wood and Cellulose, which are predominantly located in the cities of Araucária, São José dos Pinhais and Curitiba. Finally, the analysis of regional decomposition shows that most of the industrial sectors in the MRC have a high degree of regional leakage of the production multiplier. Keywords: Regional input-output matrix. Metropolitan Region of Curitiba. Structural Indicators. Model Interregional Input-Output Adjustment System -IIOAS

Raw poultry meatballs with soya flour: Shelf life and nutritional value

Poultry meat is a valuable source of protein for human consumption. It plays an important role in countries with poor ungulate meat production, including the Republic of Kazakhstan. The intake of fibre by the Kazakh population also remains low, while the intake of saturated fatty acids is excessive. Therefore, it is recommended to combine meat with plant products, e.g. soya flour. In the present research, we developed and evaluated a new meatball product containing different amounts of soya flour. The meatballs proved to be a semi-finished high-protein product. They also demonstrated a good fatty acid and mineral profile. The product with 30% of soya flour showed the best results: 27% of protein, low content of saturated fatty acid, and shelf life of 48 h. To extend the shelf life of the meatballs under refrigerator conditions, new disinfection methods should be developed.S

Bacterial Diversity of Breast Milk in Healthy Spanish Women: Evolution from Birth to Five Years Postpartum

The objective of this work was to characterize the microbiota of breast milk in healthy Spanish mothers and to investigate the effects of lactation time on its diversity. A total of ninety-nine human milk samples were collected from healthy Spanish women and were assessed by means of next-generation sequencing of 16S rRNA amplicons and by qPCR. Firmicutes was the most abundant phylum, followed by Bacteroidetes, Actinobacteria, and Proteobacteria. Accordingly, Streptococcus was the most abundant genus. Lactation time showed a strong influence in milk microbiota, positively correlating with Actinobacteria and Bacteroidetes, while Firmicutes was relatively constant over lactation. 16S rRNA amplicon sequencing showed that the highest alpha-diversity was found in samples of prolonged lactation, along with wider differences between individuals. As for milk nutrients, calcium, magnesium, and selenium levels were potentially associated with Streptococcus and Staphylococcus abundance. Additionally, Proteobacteria was positively correlated with docosahexaenoic acid (DHA) levels in breast milk, and Staphylococcus with conjugated linoleic acid. Conversely, Streptococcus and trans-palmitoleic acid showed a negative association. Other factors such as maternal body mass index or diet also showed an influence on the structure of these microbial communities. Overall, human milk in Spanish mothers appeared to be a complex niche shaped by host factors and by its own nutrients, increasing in diversity over timeThe authors would like to thank the European Regional Development Funds (FEDER), grant ED431C 2018/05, for covering the costs of publicationS

Assessment of the presence of Acinetobacter spp. resistant to β-lactams in commercial ready-to-eat salad samples

Acinetobacter baumannii is a well-known nosocomial infection causing agent. However, other Acinetobacter spp. have also been implicated in cases of human infection. Additionally, these bacteria are known for the development of antibiotic resistance thus making the treatment of the infections they cause, challenging. Due to their relevance in clinical setups less attention has been paid to their presence in foods, and its relation with infection/ dissemination routes. In the current study commercial Ready-To-Eat (RTE) salads were analyzed seeking for antibiotic resistant Acinetobacter spp. A preliminary screening allowed us to recover Gram-negative bacteria resistant to β – lactams using cefotaxime, third generation cephalosporins, as the selective agent, and this was followed by identification with CHROMagar™ Acinetobacter and 16S rDNA sequencing. Finally, the isolates identified as Acinetobacter spp. were reanalyzed by PCR to determine the presence of nine potential Extended Spectrum β Lactamases (ESBL). Two commercial RTE salad brands were included in the study (2 batches per brand and 8 samples of each batch making a total of 32 independent samples), and compared against an organic lettuce. High concentrations of β – lactam, resistant bacteria were found in all the samples tested (5 log CFU/g). Additionally, 209 isolates were phenotypically characterized on CHROMagar Acinetobacter. Finally, PCR analysis identified the presence of different ESBL genes, being positive for blaACC, blaSHV, blaDHA and blaVEB; out of these, blaACC was the most prevalent. None of the isolates screened were positive for more than one gene. To conclude, it is important to highlight the fact that pathogenic species within the genus Acinetobacter spp., other than A. baumannii, have been identified bearing resistance genes not typically associated to these microorganisms highlight the importance of continuous surveillance.info:eu-repo/semantics/publishedVersio

High-Throughput Platforms in Real-Time PCR and Applications

The miniaturization of reactions by designing nanoliter-scale PCR platforms, as Taqman® OpenArray®, Dynamic Array™, or SmartChip, has been a big step forward in real-time PCR. Each platform has some particular characteristics that differentiate them. These nanoliter-scale PCR platforms enable substantial savings in the amount of reagents and sample because the reaction volumes are at nanoliter levels. In addition, it is possible to perform thousands of reactions in a few hours. Therefore, high-throughput real-time PCR platforms result in promising systems that are capable of processing a large number of samples simultaneously and also to perform a large number of assays per sample. All of this can be translated in the amazing applicability of this technology in all kinds of analytical fields, such as medical research, animal science, and food safety, among others

Human Milk Oligosaccharides (HMOs) and Infant Microbiota: A Scoping Review

Human milk oligosaccharides (HMOs) are the third most abundant solid component of breast milk. However, the newborn cannot assimilate them as nutrients. They are recognized prebiotic agents (the first in the newborn diet) that stimulate the growth of beneficial microorganisms, mainly the genus Bifidobacterium, dominant in the gut of breastfed infants. The structures of the oligosaccharides vary mainly according to maternal genetics, but also other maternal factors such as parity and mode of delivery, age, diet, and nutritional status or even geographic location and seasonality cause different breast milk oligosaccharides profiles. Differences in the profiles of HMO have been linked to breast milk microbiota and gut microbial colonization of babies. Here, we provide a review of the scope of reports on associations between HMOs and the infant gut microbiota to assess the impact of HMO compositionS