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AIMS: This study aimed to assess the antimicrobial potential of Bp1-AdE, produced by Bacillus pumilus 64-1, and to investigate its mode of action against Staphylococcus aureus and methicillin-resistant S. aureus (MRSA). METHODS AND RESULTS: Bp-1AdE, derived from sponge-associated B. pumilus, exhibited bactericidal activity at 1 550 µg ml-1 against S. aureus ATCC29213 and MRSA strains. Light and fluorescence microscopy revealed drastic cell lysis of S. aureus treated with Bp-1AdE. Scanning and transmission electron microscopy suggested that Bp-1AdE disrupts the cytoplasmic membrane. Toxicity assays showed that Bp-1AdE was non-toxic to Tenebrio molitor larvae. Liquid chromatography-mass spectrometry and Global Natural Product Social spectral libraries identified four substances within Bp-1AdE, including aliphatic alcohols [3,4-dipentylhexane-2,5-diol and 1,1'-(4,5-dibutyl-3,6-dimethylcyclohexane-1,2-diyl)bis(ethan-1-one)] and terpenoids (cholic acid and canrenone). CONCLUSIONS: Bp-1AdE demonstrated selective toxicity and bactericidal activity, highlighting its potential for controlling infections caused by multidrug-resistant S. aureus strains.

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Ketamine is a dissociative anesthetic that induces a shift in global consciousness states and related brain dynamics. Portable low-density EEG systems could be used to monitor these effects. However, previous evidence is almost null and lacks adequate methods to address global dynamics with a small number of electrodes. This study delves into brain high-order interactions (HOI) to explore the effects of ketamine using portable EEG. In a double-blinded cross-over design, 30 male adults (mean age = 25.57, SD = 3.74) were administered racemic ketamine and compared against saline infusion as a control. Both task-driven (auditory oddball paradigm) and resting-state EEG were recorded. HOI were computed using advanced multivariate information theory tools, allowing us to quantify nonlinear statistical dependencies between all possible electrode combinations. Ketamine induced an increase in redundancy in brain dynamics (copies of the same information that can be retrieved from 3 or more electrodes), most significantly in the alpha frequency band. Redundancy was more evident during resting state, associated with a shift in conscious states towards more dissociative tendencies. Furthermore, in the task-driven context (auditory oddball), the impact of ketamine on redundancy was more significant for predictable (standard stimuli) compared to deviant ones. Finally, associations were observed between ketamine's HOI and experiences of derealization. Ketamine appears to increase redundancy and HOI across psychometric measures, suggesting these effects are correlated with alterations in consciousness towards dissociation. In comparisons with event-related potential (ERP) or standard functional connectivity metrics, HOI represent an innovative method to combine all signal spatial interactions obtained from low-density dry EEG in drug interventions, as it is the only approach that exploits all possible combinations between electrodes. This research emphasizes the potential of complexity measures coupled with portable EEG devices in monitoring shifts in consciousness, especially when paired with low-density configurations, paving the way for better understanding and monitoring of pharmacological-induced changes.

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OBJECTIVES: To determine the proportion of pediatric randomized controlled trials (RCTs) that are prematurely discontinued, examine the reasons for discontinuation, and compare the risk for recruitment failure in pediatric and adult RCTs. STUDY DESIGN: A retrospective cohort study of RCTs approved by 1 of 6 Research Ethics Committees (RECs) in Switzerland, Germany, and Canada between 2000 and 2003. We recorded trial characteristics, trial discontinuation, and reasons for discontinuation from protocols, corresponding publications, REC files, and a survey of trialists. RESULTS: We included 894 RCTs, of which 86 enrolled children and 808 enrolled adults. Forty percent of the pediatric RCTs and 29% of the adult RCTs were discontinued. Slow recruitment accounted for 56% of pediatric RCT discontinuations and 43% of adult RCT discontinuations. Multivariable logistic regression analyses suggested that pediatric RCT was not an independent risk factor for recruitment failure after adjustment for other potential risk factors (aOR, 1.22; 95% CI, 0.57-2.63). Independent risk factors were acute care setting (aOR, 4.00; 95% CI, 1.72-9.31), nonindustry sponsorship (aOR, 4.45; 95% CI, 2.59-7.65), and smaller planned sample size (aOR, 1.05; 95% CI 1.01-1.09, in decrements of 100 participants). CONCLUSION: Forty percent of pediatric RCTs were discontinued prematurely, owing predominately to slow recruitment. Enrollment of children was not an independent risk factor for recruitment failure.

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In the past few years, many studies revealed a remarkable genetic variability in Bacteroides fragilis species, and the existence of two divisions was proposed according to presence or absence of the cfiA (metallo-ß-lactamase/carbapenemase) gene. The aim of this study was to evaluate the use of DNA sequence analysis for glutamate dehydrogenase (gdh), phosphoglucomutase (pgm) and esterase (est) metabolic genes, in comparison to RNA polymerase ß subunit (rpoB) and 16S ribosomal RNA (rrs) gene sequencing, to identify the presence of these two groups in seventeen B. fragilis strains. Based on phylogenetic trees, only the est gene sequences generated a classification similar to rrs- and rpoB-genes. On the other hand, the genes pgm and gdh did not allow the discrimination of these divisions. The est gene sequence can be suggested as an additional tool for differentiation of the two groups in B. fragilis, providing highly reproducible and reliable data in B. fragilis taxonomy.

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In this study, hypotheses concerning the use of beach ashtrays were experimentally tested. Results indicated that the mean rate of abandonment of this equipment was low (1.5 percent). The mean amount of cigarette stubs (3.4 items/ashtray) was greater than mean amounts of other types of litter. People with different socioeconomic profiles had different perceptions regarding the issues associated with beach debris. These results indicated that beach ashtrays could be useful to prevent the contamination of these environments and that differences in socioeconomic characteristics of beachgoers could partially explain the differences in perceptions regarding the presence of waste on the beaches. This information could now be used by coastal managers to plan strategies to reduce the marine contamination.

A presença de resíduos sólidos no ambiente marinho é extensa. Praias são tipicamente contaminadas com esses materiais, que podem causar impactos ecológicos. Resíduos sólidos nas praias podem causar ferimentos nas pessoas e podem prejudicar a atividade turística. Neste estudo, hipóteses relativas ao uso de cinzeiros de praia foram testadas. Os resultados indicam que a taxa de abandono desse equipamento é pequena (1,5 por cento) e que a quantidade média de pontas de cigarro (3,4 itens/cinzeiro) é maior do que as quantidades médias de outros tipos de lixo. Também se observou que pessoas com diferentes perfis socioeconômicos apresentaram percepções diferentes relativas à presença de resíduos sólidos nas praias. Estes resultados sugerem que cinzeiros portáteis podem ser um equipamento importante na redução da contaminação das praias e que diferenças socioeconômicas dos freqüentadores das praias podem explicar parcialmente as diferentes percepções relativas à presença de resíduos no ambiente praial. Sugere-se que os gerentes costeiros usem esse tipo de informação para planejar estratégias de redução desse problema.

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ELISAs for paratuberculosis employ a preadsorption step with Mycobacterium phlei to diminish unspecific reactions As M. fortuitum is one of the most frequent environmental mycobacteria, the purpose of this pilot study was to evaluate its use as an alternative for the preadsorption in ELISAs for paratuberculosis. Results suggest that M. fortuitum can be an alternative instead of or associated to M. phlei with comparable results (κ > 0.8) to conventional ELISAs using M. phlei as a preadsorption antigen.

Ensaios de sorodiagnóstico de paratuberculose (ELISA) utilizam Mycobacterium phlei na etapa de pré-adsorção para diminuir reações inespecíficas. Uma vez que M. fortuitum é uma das micobactérias atípicas mais isoladas no Brasil, o objetivo central deste estudo foi averiguar a possibilidade de sua utilização como antígeno da etapa de pré-adsorção destes testes. Os resultados sugerem que M. fortuitum apresentou resultados comparáveis (κ > 0.8) aos alcançados com M. phlei e que, portanto poderia ser uma alternativa ao invés ou associado a M. phlei na etapa de pré-adsorção de ELISAs para paratuberculose.

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ELISAs for paratuberculosis employ a preadsorption step with Mycobacterium phlei to diminish unspecific reactions As M. fortuitum is one of the most frequent environmental mycobacteria, the purpose of this pilot study was to evaluate its use as an alternative for the preadsorption in ELISAs for paratuberculosis. Results suggest that M. fortuitum can be an alternative instead of or associated to M. phlei with comparable results (κ > 0.8) to conventional ELISAs using M. phlei as a preadsorption antigen.

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In spite of the large number of goats found in several developing tropical countries, milk production remains unsatisfactory. The occurrence of infectious diseases, such as leptospirosis, brucellosis and caprine arthritis-encephalitis (CAE) may in part be responsible for sub-optimal production. In this study, 1000 serum samples were tested for leptospirosis, 953 for brucellosis and 562 for CAE. All tested flocks presented at least one seroreactive animal for leptospirosis and for CAE. Reactivity to leptospirosis was 11.1%, and serovar hardjo was the most frequently found. Anti-B. abortus agglutinins were found in 0.5% of the samples presented and 14.1% were seroreactive to CAE. Leptospirosis was considered to represent the major infectious problem in the studied goat flocks. The occurrence of infectious diseases in the tested flocks may represent an important factor contributing to the decreased productivity of the animals. These findings may be similar to those observed in other developing countries and require further study to define the relationship between seropositivity and reduced production.

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