"Relationship between antibiotic resistance, biofilm formation, virulence factors and source of origin of Pseudomonas aeruginosa environmental isolates with regard to the presence of metallo-ß-lactamase-encoding genes".

A total of 557 water samples were evaluated and of these, 23 were positive for the presence of Pseudomonas aeruginosa. Approximately 91.7% of them were weak biofilm formers. Only 4 isolates showed antimicrobial resistance. All isolates presented Twitching motility, a positive result for the production of pyocyanin, alkaline protease, and hemolysins. The genotypic tests showed: lasA, (95.6%) lasB (95.6%), exoS (95.6%), exoT (91.3%), toxA (91.3%), akgO (91.3%), plcN (91.3%) aprA (86.9%), phzM (78.3%), and pvdA (60.9%). For genes encoding metallo-beta-lactamase, it was found: blaVIM (56.6%), blaSPM (4.3%), and blaSIM (47.8%). A strong association was found between the metallo-beta-lactamase producing genes, nine genes of virulence factors and the motility (r = 0.6231). The very close clonal profile suggests a probable similarity between the isolates from different cities. Thus, P. aeruginosa can be present in water supplies with variable virulence capacities and can generate a huge concern for human, animal, and environmental health.

Effect of Biogenic Silver Nanoparticles on the Quorum-Sensing System of Pseudomonas aeruginosa PAO1 and PA14.

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.

Fungi in dialysis water and dialysate: occurrence, susceptibility to antifungal agents and biofilm production capacity.

The aim of this study was to investigate the occurrence of fungi in dialysis water and dialysate, in addition to evaluating the susceptibility to antifungals and the biofilm production capacity of isolated microorganisms. The samples were collected in three hemodialysis units in Bauru (Brazil), every 15 days (July 2017-June 2018) at post-reverse osmosis, reuse, and dialysate points. The fungi were isolated by spread plate on Sabouraud dextrose agar. Filamentous fungi were phenotypically identified and yeasts were subjected to molecular evaluation of the ITS region. Susceptibility test to antifungals was carried out by the broth microdilution method and biofilm production capacity was evaluated in microtiter plates using crystal violet staining. Fungi were isolated in 52/216 (24.1%) samples, with an average count of 16.3 (10-40) CFU/mL. Overall, 61 microorganisms were identified, with 54 (88.5%) filamentous fungi and 7 (11.5%) yeasts. The main genera included were Penicillium, Cladosporium, Scedosporium, Rhinocladiella, Fusarium, and Emmonsia. Most isolates showed high values of minimum inhibitory concentration for 5-flucytosine and fluconazole and 35/45 (77.8%) isolates were classified as strong producers of biofilm. In order to increase the safety of the dialysis process, the adoption of control measures and monitoring of fungi in hemodialysis fluids is suggested.

Subinhibitory Concentrations of Biogenic Silver Nanoparticles Affect Motility and Biofilm Formation in Pseudomonas aeruginosa.

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.

Profile of pro-inflammatory cytokines in colostrum of nursing mothers at the extremes of reproductive age.

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)-1ß 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.

Quorum sensing system: Target to control the spread of bacterial infections.

Quorum Sensing (QS) systems regulate the gene expression of different types of virulence factors in accordance with the cell population density. A literature search was performed, including electronic databases such as MEDLINE/PubMed, SciELO, and LILACS, as well as other databases not indexed, such as Google Scholar. The search was conducted between July 2018 and April 2019, through online research. Antimicrobial resistance is one of the biggest threats to global health and the dissemination of resistant microbes in the environment is a major public health problem. Therefore, it is important to develop new therapies to control the spread of resistant bacteria to humans. Thus, interference in the chemical signal (autoinducers) of the QS system has been postulated as a good alternative, technically known as "Quorum Quenching" or QS inhibitors. Inhibition of QS signaling is not intended to kill the microorganism, but to block the expression of the target genes, making the cells less virulent and more vulnerable to host immune response. Anti-virulence therapy by agents that interfere with this system in pathogenic bacteria is a well-studied strategy, including medicinal plants and their bioactive constituents, and presents good prospects. This review aims to provide an overview of the QS system in bacteria and describe the main inhibitors of the system.

Maternal age influence in human colostrum acidity composition in a Maternity in an country side city of São Paulo State / Impacto da idade materna na acidez do colostro de nutrizes em maternidade do interior do Estado de São Paulo

INTRODUCTION: OBJECTIVE: To analyze sociodemographic and gestational characteristics and to compare colostrum acidity content in adolescent and advanced maternal age mothers METHODS: This cross-sectional study included 98 adolescents (up to 18 year-old) and 33 advanced maternal age (more than 35 year-old) mothers admitted at the maternity of Presidente Prudente Regional Hospital, Brazil. An approximated volume of 10 mL of colostrum was obtained by manual expression of the breasts within 72h postpartum and stored at -20ºC up to processing. Acidity of colostrum was evaluated in Dornic degrees. Statistical analysis was performed using Mann-Whitney test or X² RESULTS: The median age adolescents and advanced maternal age mothers were 20 years (12-24) 37 years (35-45), respectively. The majority of the adolescents (66.3%) were primiparous and C-section delivery had occurred in 66.7% of advanced age mothers. Gestational body mass index (BMI) was statically higher in advanced maternal age women (32.17±5.6 vs 26.09±3.6, p< 0.0001). Acidity measurement was similar between the studied groups CONCLUSIONS: Sociodemographic and gestational characteristics of adolescents and advanced age mothers showed population heterogeneity, thus, specific follow up and orientations should be applied at each one. Colostrum constitution was constant regarding casein and proteins content, independently of maternal age

INTRODUÇÃO: 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 98 nutrizes 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

Identificação laboratorial da coqueluche na região do oeste do Estado de São Paulo / Laboratory identification of pertussis in the western region of São Paulo, Brasil

O objetivo deste estudo foi de confirmar laboratorialmente os casos suspeitos de coqueluchena região oeste do Estado de São Paulo, ocorridos entre 2010 a 2015. A cultura foi realizadano Centro de Laboratório Regional - Instituto Adolfo Lutz de Presidente Prudente e a PCR emtempo real (qPCR) foi realizada no Centro de Referência Nacional para Pertussis – Instituto AdolfoLutz em São Paulo, SP. Foram recebidas 189 amostras, sendo 29 (15,3%) confirmadas segundoos critérios laboratoriais (cultura e/ou qPCR). A faixa etária mais acometida foi em criançasmenores de seis meses de idade (82,8%), não vacinados ou com o esquema de vacinação incompleto.Provavelmente, estes resultados representam apenas uma fração do número real de casos decoqueluche que ocorrem no Brasil. O contínuo monitoramento da doença e informações daprevalência por faixa etária são importantes ferramentas para melhorar as estratégias de imunizaçãocomo forma de controlar esta doença reemergente.

The aim of this study was to confirm the suspected cases of pertussis in the Western region ofthe Sao Paulo State from 2010 to 2015. The samples were cultured in the Instituto Adolfo Lutz -Regional Laboratory of Presidente Prudente-SP, and the qPCR was performed at the NationalReference Laboratory for Pertussis – Central Instituto Adolfo Lutz, São Paulo-SP. In this period,189 samples were received, being 29 (15.3%) confirmed by the laboratory criteria (culture and/orqPCR). The most affected group was the children less than six months old (82.8%), not vaccinatedor with the incomplete vaccination. Most likely, these results only represent a fraction of theactual number of pertussis cases occurring in Brazil. The continuous disease monitoring and theprevalence data by age group are fundamental to improve the immunization strategies as a way tocontrol this important re-emerging disease.

Identificação laboratorial da coqueluche na região do oeste do Estado de São Paulo / Laboratory identification of pertussis in the western region of São Paulo State, Brazil

O objetivo deste estudo foi de confirmar laboratorialmente os casos suspeitos de coqueluche na região oeste do Estado de São Paulo, ocorridos entre 2010 a 2015. A cultura foi realizada no Centro de Laboratório Regional - Instituto Adolfo Lutz de Presidente Prudente e a PCR em tempo real (qPCR) foi realizada no Centro de Referência Nacional para Pertussis – Instituto Adolfo Lutz em São Paulo, SP. Foram recebidas 189 amostras, sendo 29 (15,3%) confirmadas segundo os critérios laboratoriais (cultura e/ou qPCR). A faixa etária mais acometida foi em crianças menores de seis meses de idade (82,8%), não vacinados ou com o esquema de vacinação incompleto. Provavelmente, estes resultados representam apenas uma fração do número real de casos de coqueluche que ocorrem no Brasil. O contínuo monitoramento da doença e informações da prevalência por faixa etária são importantes ferramentas para melhorar as estratégias de imunização como forma de controlar esta doença reemergente.

The aim of this study was to confirm the suspected cases of pertussis in the Western region of the Sao Paulo State from 2010 to 2015. The samples were cultured in the Instituto Adolfo Lutz - Regional Laboratory of Presidente Prudente-SP, and the qPCR was performed at the National Reference Laboratory for Pertussis – Central Instituto Adolfo Lutz, São Paulo-SP. In this period, 189 samples were received, being 29 (15.3%) confirmed by the laboratory criteria (culture and/or qPCR). The most affected group was the children less than six months old (82.8%), not vaccinated or with the incomplete vaccination. Most likely, these results only represent a fraction of the actual number of pertussis cases occurring in Brazil. The continuous disease monitoring and the prevalence data by age group are fundamental to improve the immunization strategies as a way to control this important re-emerging disease.