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Salmonella enterica subspecies enterica serovars Enteritidis and Typhimurium are important causes of foodborne illness. Methods for simultaneous detection of these serovars may contribute for the adoption of measures to prevent these diseases. The polymerase chain reaction to detect individually or simultaneously the serovars Enteritidis and Typhimurium in foods have been standardized; however, the majority of assays employ the fliC gene as a target for detection of serovar Typhimurium. The detection of these sorovars in a few hours allows the food supply chain to take appropriate measures to prevent the distribution of contaminated food. The aim of this study was to develop a new multiplex PCR (mPCR) for the simultaneous detection and differentiation of Salmonella spp., S. Enteritidis and S. Typhimurium in chicken meat. The mPCR assays showed high specificity and differentiated S. Typhimurium from 22 Salmonella serovars tested, including S. Kentucky, showing that it's an alternative to reduce the time required to obtain presumptive positive results. PRACTICAL APPLICATIONSThe fliC gene used as target for the detection of serovar Typhimurium is questionable as it has also been described for S. Kentucky. The amplification of STM4492 gene in this study, instead of fliC gene, exhibited high specificity to detect S. Typhimurium. The developed mPCR is an efficient means for the simultaneous detection and differentiation of Salmonella spp., S. Enteritidis and S. Typhimurium in chicken meat after 24 h of enrichment. The mPCR has the potential to be used in routine diagnostic laboratories to obtain presumptive positive results and for identification of Enteritidis and Typhimurium strains isolated by the conventional method. bs_bs_banner Journal of Food Safety ISSN 1745-4565

Biogenic silver nanoparticles (bio-AgNPs) are increasingly recognized as an antibiofilm and antivirulence strategy against P. aeruginosa, a bacterium that causes chronic infections in immunocompromised and cystic fibrosis patients. This study aimed to investigate the effects of subinhibitory concentrations of bio-AgNPs on motility and biofilm formation in P. aeruginosa. Bio-AgNPs were synthesized via reduction of ionic silver catalyzed by cell-free culture filtrate from Fusarium oxysporum. A total of 17 P. aeruginosa isolates and strains were evaluated for swarming, swimming, and twitching motility in the presence and absence (control) of bio-AgNPs, including 10 clinical isolates from patients with and without cystic fibrosis, 5 environmental isolates obtained from the public water supply system, and 2 reference strains (PAO1 and PA14). Isolates were identified by biochemical and molecular methods. Minimum inhibitory concentrations (MICs) were determined by the broth microdilution method. Swarming, swimming, and twitching motility assays were performed in Petri dishes. Biofilm formation capacity was assessed quantitatively by the crystal violet method. MIC values ranged from 15.62 to 62.50 µM. The results showed that subinhibitory concentrations of bio-AgNPs (½ MIC, 7.81–31.25 µM) significantly increased (p < 0.05) swarming, swimming, and twitching motility in 40.0, 40.0, and 46.7% of isolates, respectively. Subinhibitory bio-AgNP treatment enhanced (p < 0.05) biofilm formation capacity in PA14 and a cystic fibrosis isolate (P11). It is concluded that subinhibitory concentrations of bio-AgNPs increased biofilm formation and swarming, swimming, and twitching motility in PA14 and some P. aeruginosa isolates. These virulence factors are directly involved with quorum-sensing systems. Further research should investigate the effects of AgNPs on P. aeruginosa quorum sensing to help elucidate their mechanism of action at subinhibitory concentrations.

Gestations at the extremes of reproductive age are characterized as high-risk pregnancies, conditions that might influence colostrum composition. This first milk secretion contains nutrients necessary for the development and immunity of the newborn; therefore, this study aims to compare adolescent and advanced maternal age mothers regarding sociodemographic, gestational, and perinatal characteristics and the colostrum levels of pro-inflammatory cytokines in these groups of study. This cross-sectional study has compared sociodemographic, gestational and perinatal data from adolescent mothers (between 10 and 24 years old) (n = 117), advanced maternal age mothers (over 35 years of age) (n = 39) and mothers considered a control group (25 to 34 years old) (n = 58). Additionally, colostrum samples were obtained from the studied and control group subjects by manual milking, between 48 and 72 hours postpartum, and the samples were analyzed for cytokine concentrations by enzyme-linked immunosorbent assay (ELISA). The majority of the studied mothers reported living a stable union, and 81.2% of the adolescent mothers did not carry out any paid activity. Mothers with advanced maternal age mainly delivered by cesarean section and presented a higher body mass index (BMI). Neonatal weight and Apgar score were not different between the groups. The concentrations of interleukin (IL)-1β and IL-6 were higher in the colostrum of mothers with advanced age compared to adolescent mothers, but did not differ from the control group. The concentrations of IL-8 and tumor necrosis factor alpha did not differ between the three groups. Therefore, our data demonstrated that maternal age influenced the sociodemographic and gestational characteristics as well as the composition of colostrum cytokines.

RESUMO -A mastite é um dos fatores que mais gera prejuízos à produção e industrialização do leite. O objetivo deste trabalho foi isolar a espécie Staphylococcus aureus das amostras de leite provenientes de 63 animais portadores de mastite, e verificar o seu perfil de sensibilidade antimicrobiana aos antibióticos comerciais e ao extrato de própolis à 30%. Dos 63 animais avaliados, 38 (60,32%) apresentaram crescimento de Staphylococcus aureus. Quanto ao teste de sensibilidade antimicrobiana, os antibióticos mais eficientes foram gentamicina (10 g), cefalexina (30 g) e ciprofloxacina (10 µg) com 100% de eficácia, seguida de norfloxacina (94,6%). Houve 35 (92,10%) animais com sensibilidade ao extrato alcoólico de própolis a 30%, com diâmetros de inibição entre 6 e 18 mm frente a volumes de 40L e 60 L. A investigação da sensibilidade antimicrobiana in vitro para cepas de Staphylococcus aureus isoladas de mastite bovina é de grande importância antes da indicação do seu tratamento terapêutico. O uso do extrato alcoólico de própolis a 30% na terapia antimicrobiana pode ser uma alternativa, pois seus componentes conferem-lhe grande valor na medicina natural popular e preventiva.Palavras-Chave: Antibiótico, mastite clínica, mastite subclínica, resistência.ABSTRACT -Mastitis is one of the factors that cause damage to production and processing milk. The aim of this study was to isolate the species Staphylococcus aureus from milk samples from 63 animals with mastitis, and check your profile antimicrobial sensitivity to antibiotics and the extract of propolis at 30%. Of 63 animals evaluated, 38 (60.32%) showed growth of Staphylococcus aureus. As for testing of antimicrobial sensitivity test, the most efficient antibiotics were gentamicin (10 g), cephalexin (30 g) and ciprofloxacin (10 g) with 100% efficiency, followed by norfloxacin (94.6%). There were 35 (92.10%) animals with sensitivity to the extract of propolis 30% with inhibition diameters between 6 and 18 mm in 40 L and 60 L. The investigation of in vitro antimicrobial susceptibility to Staphylococcus aureus isolated from bovine mastitis is extremely valuable to their treatment. The use of extract of propolis 30% in the antimicrobial therapy may be an alternative, because its components gives it excellent value in natural medicine and preventive.

Objetivo: Analisar as características sociodemográficas e gestacionais e comparar a acidez do colostro de nutrizes adolescentes e idade materna avançada. Método: Estudo prospectivo transversal, que incluiu 98nutrizes adolescentes (até 18 anos) e 33 nutrizes com idade materna avançada (maior que 35) atendidas na Maternidade do Hospital Regional de Presidente Prudente. Amostras de aproximadamente 10 mL de colostro foram obtidas por meio da ordenha manual entre 48 a 72h após o parto, e armazenadas a -20oC até o processamento. A acidez foi verificada por meio da titulação e calculada em graus Dornic. A análise estatística foi realizada utilizando-se o teste de Mann-Whitney ou X2. Resultados: A mediana da idade materna das nutrizes adolescentes foi de 20 (12-24) anos, e das nutrizes com idade materna avançada foi de 37 (35-45) anos. A maioria das nutrizes adolescentes (66,3%) eram primíparas e a via de parto cesárea  ocorreu em 66,7% das nutrizes em idade materna avançada. O índice de massa corpórea (IMC) gestacional foi estatisticamente maior em nutrizes com idade materna avançada (31,3±5,6 vs 26,06±3,6, p< 0,0001). A acidez do colostro das nutrizes nos extremos da idade reprodutiva não apresentou diferença significativa entre os grupos de nutrizes. Conclusão: As características sociodemográficas e gestacionais de adolescentes e mães com idade materna avançada evidenciam heterogeneidade dessas populações e consequentemente, atendimento e condutas específicas devem ser aplicados a cada uma. A constituição do colostro em caiseina e proteinas apresentou-se constante, independente da idade materna.

A bactéria Pseudomonas aeruginosa está amplamente distribuída no ambiente. A pouca exigência nutricional deste microrganismo possibilita sua sobrevivência em água de abastecimento público, cuja importância para a saúde pública deve-se principalmente ao fato de causar infecções em indivíduos imunocomprometidos. O objetivo deste trabalho foi avaliar fenotipicamente os fatores de virulência de P. aeruginosa obtidos de água de abastecimento público. Um total de 19 isolados de P. aeruginosa foram analisados para determinação das motilidades (swarming, swimming e twitching), e avaliação da produção de protease alcalina, ramnolipídeos e DNase. Os experimentos foram realizados em triplicata em três ocasiões distintas. Para realizar a representação gráfica e a análise estatística foi utilizado o Software R Studio (1.2.5001). Todos os isolados foram produtores de protease alcalina com halo de proteólise acima de 8 mm. A atividade da DNase e a produção de ramnolipídeos foram observadas em 21,1% (n=4) e 84,2% (n=16), respectivamente. Os resultados mostraram uma alta diversidade no comportamento de motilidade entre os isolados de P. aeruginosa. Ao comparar os três tipos de motilidade, a maioria dos isolados (68,4%) apresentou produção significativa (p0,05) de motilidade swimming. Conclui-se que os isolados de P. aeruginosa testados foram capazes de produzir fatores de virulência como motilidade swimming e twitching, protease e ramnolipídeos.

The increase in multidrug-resistant microorganisms represents a global threat requiring the development novel strategies to fight bacterial infection. This study aimed to assess the effect of silver nanoparticles (bio-AgNPs) on bacterial growth, biofilm formation, production of virulence factors, and expression of genes related to the quorum-sensing (QS) system of P. aeruginosa PAO1 and PA14. Biofilm formation and virulence assays were performed with bio-AgNPs. RT-qPCR was carried out to determine the effect of bio-AgNPs on the QS regulatory genes lasI, lasR, rhlI, rhlR, pqsA, and mvfR. Bio-AgNPs had an MIC value of 62.50 μM, for both strains. Phenotypic and genotypic assays were carried out using sub-MIC values. Experimental results showed that treatment with sub-MICs of bio-AgNPs reduced (p < 0.05) the motility and rhamnolipids and elastase production in P. aeruginosa PAO1. In PA14, bio-AgNPs stimulated swarming and twitching motilities as well as biofilm formation and elastase and pyocyanin production. Bio-AgNP treatment increased (p < 0.05) the expression of QS genes in PAO1 and PA14. Despite the different phenotypic behaviors in both strains, both showed an increase in the expression of QS genes. Demonstrating that the bio-AgNPs acted in the induction of regulation. The possible mechanism underlying the action of bio-AgNPs involves the induction of the rhl and/or pqs system of PAO1 and of the las and/or pqs system of PA14. These results suggest that exposure to low concentrations of bio-AgNPs may promote the expression of QS regulatory genes in P. aeruginosa, consequently inducing the production of virulence factors such as elastase, pyocyanin, and biofilms.