Activity the phenolic extract of pitanga on the formation of biofilms of Serratia liquefaciens

Biofilme é um conglomerado de células aderidas a uma superfície, envolvidas em uma matriz de exopolímeros (EPS). É resistente a antimicrobianos tornando difícil sua erradicação. Alternativas para o controle do biofilme estão sendo pesquisadas e os compostos naturais têm apresentado importantes resultados ao interferirem na comunicação pelo mecanismo de quorum sensing. Visando avaliar o efeito de concentrações sub-inibitórias (sub-MIC) do extrato fenólico de pitanga (Eugenia uniflora L.; EFP) sobre a formação de biofilme de Serratia liquefaciens L53. Pitangas foram coletadas, despolpadas e realizou-se a extração purificando os compostos fenólicos utilizando extração em fase sólida (mini-coluna C18). Os compostos fenólicos totais foram quantificados pelo ensaio do reagente Folin-Ciocalteu, identificados por análise em cromatografia líquida de alta eficiência (CLAE) e por Chromatography Electrospray Ionization Tandem Mass Spectrometric (LC-ESI-MS/MS) e a concentração inibitória mínima (MIC) para S. liquefaciens L53. Foram determinadas as concentrações sub-MIC foram avaliadas sobre a formação de biofilme total e sobre os componentes da matriz do biofilme nos tempos de 7, 48 e 168 h. Foi avaliada a susceptibilidade do biofilme de 48 h formado na presença do EFP a agentes antimicrobianos e seu efeito combinado com os antibióticos ampicilina (30 μg.mL -1 ), canamicina (10 μg.mL -1 ) e getamicina (10 μg.mL -1 ). O EFP apresentou 231 mg de ácido gálico equivalente (AGE). 100 g -1 de polpa de compostos fenólicos totais e os flavonoides majoritários identificados foram elagitaninos e derivados glicosilados de quercetina. Em concentrações sub-MIC, o EFP diminuiu a formação do biofilme total e os componentes da matriz dos EPS, polissacarídeos, proteínas e DNA, nos tempos de 7 e 48 h e, em contrapartida, aumentou em 168 h. O EFP não alterou o número de células viáveis de S. liquefaciens L53 aderidas ao poliestireno no tempo de 48 h nem a susceptibilidade ao tratamento com 200 mg.L -1 de dicloroisocianurato e 0,1 mg.mL -1 de canamicina comparados ao controle. O EFP, em uso combinado com os antibióticos, apresentou efeito antagônico com os mesmos. Nesse contexto, o uso de concentraçãos sub-MIC do EFP apresentou efeitos divergentes na formação do biofilme em função do tempo de análise, diminuindo o biofilme em menor tempo e aumentando em tempo maior de cultivo. O EFP não alterou a susceptibilidade do biofilme ao tratamento com antimicrobianos comparado ao controle e atuou como antagonista com antibióticos. Sendo assim, a utilização do EFP é controversa, pois pode apresentar efeitos indesejáveis, aumentando o biofilme no tempo maior de contato, além de apresentar efeito antagônico com antibióticos.Biofilm is a conglomerate of cells adhered to a surface, wrapped in a matrix of exopolymers (EPS). It is resistant to antimicrobials making it difficult to eradicate it. Alternatives for biofilm control are being investigated and natural compounds have shown important results by interfering in communication by the mechanism of quorum sensing. In order to evaluate the effect of subinhibitory concentrations (sub-MIC) of the phenolic extract of pitanga (Eugenia uniflora L., FEP) on the biofilm formation of Serratia liquefaciens L53. Pitangas were collected, pulped and extraction was carried out by purifying the phenolic compounds using solid phase extraction (mini C18 column). The total phenolic compounds were quantified by the Folin-Ciocalteu reagent assay, as well as identified by High Performance Liquid Chromatography (HPLC) and by Chromatography Electrospray Ionization Tandem Mass Spectrometry (LC-ESI-MS/MS). The minimum inhibitory concentration (MIC) for S. liquefaciens L53 was performed. The sub-MIC concentrations were evaluated on total biofilm formation and biofilm matrix components at 7, 48 and 168 h. The susceptibility of the 48 h biofilm formed in the presence of FEP to antimicrobial agents and their combined effect with the antibiotics ampicillin (30 μg.mL -1 ), kanamycin (10 μg.mL -1 ) and getamycin (10 μg.mL -1 ). The FEP showed 231 mg gallic acid per 100 g -1 pulp AGE. de polpa 17,133.1 per liter (AGE.L -1 ) of total phenolic compounds and the identified major flavonoids were ellagitannins and glycosylated derivatives of quercetin. In sub-MIC, concentrations, the FEP decreased of the total biofilm formation and matrix components such as EPS, polysaccharides, proteins and DNA after 7 and 48 h cultivation and increased after 168 h. The FEP did not change the number of viable cells of S. liquefaciens L53 adhered to the polystyrene in the time of 48 h nor the susceptibility to treatment with 200 mg.L -1 of dichloroisocyanurate or 0.1 mg.mL -1 of kanamycin in comparision with the control. The EFP combined with antibiotics showed an antagonistic effect. In this context, the use of sub-MIC concentrations of EFP showed divergent effects on biofilm formation as a function of the time of cultivation, reducing biofilm in a shorter time and increasing in time of culture. The EFP did not alter the susceptibility of the biofilm to antimicrobial treatment compared to control and acted as an antagonist with antibiotics. Therefore, the use of EFP is controversial, as it may present undesirable effects, increasing the biofilm in the longer time of contact, besides presenting an antagonistic effect with antibiotics.Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Atividade anti-quorum sensing de extratos de grumixama (Eugenia brasiliensis) e pitanga (Eugenia uniflora l.).

Muitas bactérias regulam a expressão gênica em resposta a sinais difusíveis produzidos de forma dependente da densidade celular, em um processo denominado quorum sensing. Esse processo ocorre por meio da produção, liberação e detecção de moléculas sinalizadoras. Os fenótipos regulados pelo quorum sensing estão envolvidos nos processos de virulência, esporulação, motilidade, produção de enzimas, bioluminescência, produção de pigmentos, entre outros. A interrupção de qualquer das etapas do sistema quorum sensing pode provocar consequências prejudiciais à virulência bacteriana. Alguns trabalhos evidenciam que extratos à base de plantas apresentam ação anti-quorum sensing, com possíveis aplicações no controle de infecções. Grumixama (Eugenia brasiliensis) e pitanga (Eugenia uniflora L.) são frutas da família das mirtáceas, nativas do Brasil, ricas em compostos fenólicos e apresentam atividade antioxidante e antimicrobiana. Foi objetivo do estudo detectar a atividade anti-quorum sensing dos extratos bruto e fenólico obtidos das frutas grumixama e pitanga em concentrações que não inibem o crescimento microbiano. Os compostos fenólicos das polpas foram extraídos e purificados utilizando extração em fase sólida (mini-coluna C18) e quantificados por espectrofotometria. A atividade anti-quorum sensing dos extratos bruto e fenólico foi avaliada empregando diferentes bactérias e a detecção de diferentes fenótipos. Chromobacterium violaceum foi avaliado pelo ensaio qualitativo de difusão em ágar e pelo teste de quantificação da inibição da produção de violaceína. Em Aeromonas hydrophila e Serratia marcescens foram avaliadas a motilidade tipo swarming e swimming e em C. violaceum, S. marcescens, A. hydrophila e Escherichia coli foi avaliada a formação de biofilme. Os extratos de ambas as frutas apresentaram inibição significativa na produção de violaceína por C. violaceum. Houve também inibição da motilidade bacteriana do tipo swarming e swimming em A. hydrophila e S. marcescens. Os extratos de ambas as frutas aumentaram a formação de biofilme em C. violaceum, A. hydrophila, S. marcescens e E. coli. Esses resultados indicam que os extratos bruto e fenólico de grumixama e pitanga apresentam atividade anti-quorum sensing sugerindo potenciais aplicabilidades nas indústrias alimentícia e farmacêutica, inibindo fenótipos regulados pelo quorum sensing.Many bacteria regulate gene expression in response to diffusible signals produced dependently on cell density, in a process called quorum sensing. This process occurs by means of producing, releasing and detecting signaling molecules. The phenotypes regulated by quorum sensing are involved in processes related to virulence, sporulation, motility, production of enzymes, bioluminescence, production of pigments, among others. Interrupting any stage of the quorum sensing system can cause detrimental effects to bacterial virulence. Some studies have shown that plant based extracts have quorum quenching effects, with possible applications in infection control. Grumixama (Eugenia brasiliensis) and pitanga (Eugenia uniflora L.) are fruits that belong to the family Myrtaceae, native to Brazil, rich in phenolic compounds and have antioxidant and antimicrobial activity. The purpose of this study was to evaluate the quorum quenching activity of crude and phenolic extracts obtained from grumixama (Eugenia brasiliensis) and pitanga (Eugenia uniflora L.) in concentrations that do not inhibit microbial growth. Phenolic compounds from the pulps were extracted and purified using solid-phase extraction (C18 mini-column) and quantified by using spectrophotometry. Quorum quenching activity of crude and phenolic extracts was evaluated using different bacteria and the detection of different phenotypes. For instance, Chromobacterium violaceum was evaluated in agar diffusion assay as well as through the quantification of violacein production; for A. hidropyla and Serratia marcescens, swarming and swimming motilities were tested and for C. violaceum, S. marcescens, A. hydrophila and Escherichia coli biofilm formation was assayed. Extracts from both fruits showed significant inhibition of violacein production by C. violaceum. There was also inhibition of bacterial swarming and swimming motilities for A. hydrophila and S. marcescens. The extracts of both fruits increased biofilm formation in C. violaceum, A. hydrophila, S. marcescens, and E. coli. These results indicate that crude and phenolic extracts from grumixama and pitanga present quorum quenching activity suggesting a potential aplication in the food and pharmaceutical industries inhibiting phenotypes regulated by quorum sensing

Anti-quorum sensing activity of phenolic extract from Eugenia brasiliensis (Brazilian cherry)

Abstract The aim of this study was to assess the anti-quorum sensing activity of phenolic extracts from grumixama (Eugenia brasiliensis), also known as Brazilian cherry, in concentrations that did not interfere with bacterial growth. The pulp phenolic compounds were extracted by using solid phage extraction in a mini-collumn C18 and quantified by spectrophotometry. The anti-quorum sensing activity was evaluated by testing the inhibition of violacein production in Chromobacterium violaceum and by evaluating the swarming motility in Aeromonas hydrophila and Serratia marcescens, both phenotypes regulated by quorum sensing. The phenolic extract strongly inhibited the production of violacein in C. violaceum, reducing its production in comparison with a control with no extract. No inhibition of growth was observed at the concentrations tested for quorum sensing inhibition. Confirming the quorum sensing inhibition phenotype, the extract was also able to inhibit swarming motility in S. marcescens and in A. hydrophila, although in the later the effect was marginal. Overall, these results indicate that phenolic extract from E. brasiliensis presents quorum sensing inhibitory activity most likely due to the presence of fruit phenolics which have been implicated as quorum sensing inhibitors in Gram negative bacteria

Mineral and centesimal contents, antioxidant activity and antimicrobial action of phenolic compounds from Eugenia Brasiliensis Lam. Pulp

Abstract Phenolic compounds (PC) have presented antioxidant potential as well as antimicrobial action against several bacteria. This study aimed to extract PC from grumixama (Eugenia brasiliensis Lam.) pulp using solid phase extraction (SPE), then quantify the PC by Folin-Ciocalteu assay, and to evaluate the antioxidant activity (AA) from PC by DPPH, ABTS and FRAP methods as well as its antimicrobial activity by plate diffusion assay (PDA) and Minimal Inhibitory Concentration (MIC) assays. Additionally, the centesimal composition of the fruit and its mineral content by Total Reflection X-Ray Fluorescence Spectroscopy were determined. The fruit is a good source of PC which presented a higher contribution on AA from pulp than NPHRC. Calcium was the trace element in highest concentration in the pulp, followed by iron. PC from grumixama inhibited the growth of Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa but not Escherichia coli and Listeria monocytogenes in the PDA. PC showed antimicrobial activity against the five microorganisms tested in the MIC assay, in which S. aureus and B. cereus were the most sensitive. This study highlights the antioxidant and antimicrobial potential of Eugenia brasiliensis Lam. as natural agent in the development of functional foods and nutraceuticals

Treinamento aeróbio contínuo versus treinamento acumulado: Uma comparação de seus efeitos e desempenho em modelo animal

Continuous aerobic training versus accumulated training, a comparison of their performance and effects in an animal modelIntroduction: Since 1995, entities that regulate the practice of physical exercises have suggested that, for health maintenance, they must be performed in continuous or accumulated throughout the day sessions. In a recent publication in 2011 this recommendation was reinforced by the American College of Sports Medicine. The question that is still not well understood is: Does exercise performed cumulatively by two or more times throughout the day is as effective in promoting the health benefits as exercise performed continuously in a single daily session? Therefore, the aim of this study was to compare the effects of aerobic exercise training performed in a continuous versus accumulated form on aerobic performance of Wistar rats. Materials and Methods: Our sample consisted of 16 male Wistar rats, with initial weights around 300 g and 90 days of life, who trained for a period of 10 weeks continuously (TC) and total (TA) in the aquatic environment. Results: after training only the TC group had increased aerobic performance compared to controls (sedentary). Conclusion: The proposed aerobic training is carried out continuously higher to improve aerobic performance of Wistar rats when compared to a similar training performed cumulatively.Desde 1995, entidades que regulamentam a prática de exercícios físicos têm sugerido que, para manutenção da saúde, os mesmos devem ser realizados em sessões contínuas ou acumulados ao longo do dia. Em publicação recente de 2011 esta recomendação foi reforçada pelo Colégio Americano de Medicina Esportiva. A questão que ainda não é bem compreendida é: Será que o exercício realizado de forma acumulada por duas ou mais vezes ao longo do dia é tão eficiente em promover os benefícios à saúde como o exercício realizado de forma contínua em uma única sessão diária? Portanto, o objetivo deste trabalho foi comparar os efeitos de um treinamento físico aeróbio realizado de forma contínua versus acumulada sobre o desempenho aeróbio de ratos Wistar. Materiais e Métodos: Nossa amostra foi constituída por 16 ratos machos da raça Wistar, com pesos iniciais em torno de 300 g e 90 dias de vida, que treinaram por um período de 10 semanas de forma contínua (TC) e acumulada (TA) em meio aquático. Resultados: após o treinamento apenas o grupo TC teve aumento do desempenho aeróbio comparado ao grupo controle (sedentário). Conclusão: O treinamento aeróbio proposto realizado de forma contínua é superior para a melhora do desempenho aeróbio de ratos Wistar quando comparado a um treinamento semelhante realizado de forma acumulada.

Long-term safety and efficacy of patisiran for hereditary transthyretin-mediated amyloidosis with polyneuropathy: 12-month results of an open-label extension study

© 2020 Elsevier Ltd. All rights reserved.Background: Hereditary transthyretin-mediated amyloidosis is a rare, inherited, progressive disease caused by mutations in the transthyretin (TTR) gene. We assessed the safety and efficacy of long-term treatment with patisiran, an RNA interference therapeutic that inhibits TTR production, in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy. Methods: This multicentre, open-label extension (OLE) trial enrolled patients at 43 hospitals or clinical centres in 19 countries as of Sept 24, 2018. Patients were eligible if they had completed the phase 3 APOLLO or phase 2 OLE parent studies and tolerated the study drug. Eligible patients from APOLLO (patisiran and placebo groups) and the phase 2 OLE (patisiran group) studies enrolled in this global OLE trial and received patisiran 0·3 mg/kg by intravenous infusion every 3 weeks with plans to continue to do so for up to 5 years. Efficacy assessments included measures of polyneuropathy (modified Neuropathy Impairment Score +7 [mNIS+7]), quality of life, autonomic symptoms, nutritional status, disability, ambulation status, motor function, and cardiac stress, with analysis by study groups (APOLLO-placebo, APOLLO-patisiran, phase 2 OLE patisiran) based on allocation in the parent trial. The global OLE is ongoing with no new enrolment, and current findings are based on the interim analysis of the patients who had completed 12-month efficacy assessments as of the data cutoff. Safety analyses included all patients who received one or more dose of patisiran up to the data cutoff. This study is registered with ClinicalTrials.gov, NCT02510261. Findings: Between July 13, 2015, and Aug 21, 2017, of 212 eligible patients, 211 were enrolled: 137 patients from the APOLLO-patisiran group, 49 from the APOLLO-placebo group, and 25 from the phase 2 OLE patisiran group. At the data cutoff on Sept 24, 2018, 126 (92%) of 137 patients from the APOLLO-patisiran group, 38 (78%) of 49 from the APOLLO-placebo group, and 25 (100%) of 25 from the phase 2 OLE patisiran group had completed 12-month assessments. At 12 months, improvements in mNIS+7 with patisiran were sustained from parent study baseline with treatment in the global OLE (APOLLO-patisiran mean change -4·0, 95 % CI -7·7 to -0·3; phase 2 OLE patisiran -4·7, -11·9 to 2·4). Mean mNIS+7 score improved from global OLE enrolment in the APOLLO-placebo group (mean change from global OLE enrolment -1·4, 95% CI -6·2 to 3·5). Overall, 204 (97%) of 211 patients reported adverse events, 82 (39%) reported serious adverse events, and there were 23 (11%) deaths. Serious adverse events were more frequent in the APOLLO-placebo group (28 [57%] of 49) than in the APOLLO-patisiran (48 [35%] of 137) or phase 2 OLE patisiran (six [24%] of 25) groups. The most common treatment-related adverse event was mild or moderate infusion-related reactions. The frequency of deaths in the global OLE was higher in the APOLLO-placebo group (13 [27%] of 49), who had a higher disease burden than the APOLLO-patisiran (ten [7%] of 137) and phase 2 OLE patisiran (0 of 25) groups. Interpretation: In this interim 12-month analysis of the ongoing global OLE study, patisiran appeared to maintain efficacy with an acceptable safety profile in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy. Continued long-term follow-up will be important for the overall assessment of safety and efficacy with patisiran.info:eu-repo/semantics/publishedVersio

Prospective observational cohort study on grading the severity of postoperative complications in global surgery research

Background The Clavien–Dindo classification is perhaps the most widely used approach for reporting postoperative complications in clinical trials. This system classifies complication severity by the treatment provided. However, it is unclear whether the Clavien–Dindo system can be used internationally in studies across differing healthcare systems in high- (HICs) and low- and middle-income countries (LMICs). Methods This was a secondary analysis of the International Surgical Outcomes Study (ISOS), a prospective observational cohort study of elective surgery in adults. Data collection occurred over a 7-day period. Severity of complications was graded using Clavien–Dindo and the simpler ISOS grading (mild, moderate or severe, based on guided investigator judgement). Severity grading was compared using the intraclass correlation coefficient (ICC). Data are presented as frequencies and ICC values (with 95 per cent c.i.). The analysis was stratified by income status of the country, comparing HICs with LMICs. Results A total of 44 814 patients were recruited from 474 hospitals in 27 countries (19 HICs and 8 LMICs). Some 7508 patients (16·8 per cent) experienced at least one postoperative complication, equivalent to 11 664 complications in total. Using the ISOS classification, 5504 of 11 664 complications (47·2 per cent) were graded as mild, 4244 (36·4 per cent) as moderate and 1916 (16·4 per cent) as severe. Using Clavien–Dindo, 6781 of 11 664 complications (58·1 per cent) were graded as I or II, 1740 (14·9 per cent) as III, 2408 (20·6 per cent) as IV and 735 (6·3 per cent) as V. Agreement between classification systems was poor overall (ICC 0·41, 95 per cent c.i. 0·20 to 0·55), and in LMICs (ICC 0·23, 0·05 to 0·38) and HICs (ICC 0·46, 0·25 to 0·59). Conclusion Caution is recommended when using a treatment approach to grade complications in global surgery studies, as this may introduce bias unintentionally

The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis

© 2017 British Journal of Anaesthesia Background: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Methods: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. Results: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32–0.77); P\u3c0.01], but no difference in complication rates [OR 1.02 (0.88–1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62–0.92); P\u3c0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61–0.88); P\u3c0.01; I2=89%). Conclusions: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine

Critical care admission following elective surgery was not associated with survival benefit: prospective analysis of data from 27 countries

This was an investigator initiated study funded by Nestle Health Sciences through an unrestricted research grant, and by a National Institute for Health Research (UK) Professorship held by RP. The study was sponsored by Queen Mary University of London