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This study aimed to identify variation in the minimum biocidal concentration (MBC) over time, comparing three commercial super-oxidized solutions with different chemical compositions. In the bactericidal assay, the following bacteria were tested: Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), and for each ATCC, one wild-type strain was used. In vitro experiments were performed in triplicate at 0, 60, and 120 days of follow up. A commercial formulation based on sodium and chloride ions (SCSS) was tested using a standard accelerated aging protocol. Data were analyzed with the Friedman and Wilcoxon signed-rank tests. The results showed that super-oxidized solution bases of 20 ppm of sodium (SSS) had a significant change in MBC at 120 days (p < 0.001), whereas SCSS remained stable during the same period (p = 0.18). However, after accelerated aging treatment, the MBC of SCSS increased (p < 0.001). With our proposed approach, the two SSS showed MBC variation at 120 days, whereas SCSS showed stability over time, similar to chlorhexidine, but lost its bactericidal properties after accelerated aging treatment.

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Infections of the oral cavity have a broad microbial etiological profile that varies according to each microenvironment in the mouth. Such infections often require antimicrobial treatment, which can lead to the development of resistance. There is thus a need to find new therapeutic strategies based on natural plant-derived compounds. The aim of this study was to determine the phytochemical nuclei and the antimicrobial effect of Anacardium excelsum leaf and stem extracts, and of fractions derived from the leaf extract, against Streptococcus mutans ATCC 25175, Staphylococcus aureus ATCC 35548, Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 19433 and Candida albicans ATCC 10231. The plant material was collected from the Quindío Botanical Garden (Calarcá, Quindío-Colombia), located at an altitude of 1500 meters above sea level. Hydroalcoholic extracts of A. excelsum leaves and stems, and fractions of the hydroalcoholic leaf extract, were obtained by percolation extraction. Phytochemical nuclei were identified by thin layer chromatography. The antimicrobial activity of the extracts and fractions (at concentrations of 2, 5, 10, 20 and 40 mg / ml) against the five ATCC reference strains was evaluated using the well diffusion technique on Mueller-Hinton agar. The leaf extract showed no antimicrobial activity against E. coli, but it did show antimicrobial activity against S. mutans, S. aureus, E. faecalis and C. albicans, at a concentration of 10 mg/ml, with zones of inhibition of 9 to 11 mm. The ethyl acetate and acetone fractions obtained from A. excelsum leaf extract had greatest antimicrobial activity at 10 mg/ml. In conclusion, (1) the A. excelsum leaf extract, and the ethyl acetate and acetone fractions obtained from the leaf extract, had the greatest antimicrobial activity on all the study microorganisms, and (2) the phytochemical nuclei in the fractions (ethyl acetate and acetone) were found to contain phenolic-type compounds, tannins, triterpene-type terpenes and steroidal-type terpenes, which might explain the antimicrobial activity observed.

Las infecciones de la cavidad bucal se caracterizan por presentar un amplio perfil etiológico microbiano que varía de acuerdo a cada microambiente en boca. En muchos casos estas infecciones requieren tratamiento antimicrobiano que puede conducir al desarrollo de resistencia. Estos hechos en conjunto generan la necesidad de buscar nuevas estrategias terapéuticas, provenientes de compuestos naturales derivados de plantas. El objetivo de este estudio fue determinar los núcleos fitoquímicos y el efecto antimicrobiano de extractos de hojas y tallos, y de fracciones derivadas del extracto de hojas de Anacardium excelsum contra Streptococcus mutans ATCC 25175, Staphylococcus aureus ATCC 35548, Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 19433 y Candida albicans ATCC 10231. El material vegetal se colectó del Jardín Botánico del Quindío (Calarcá, Quindío-Colombia), situado a una altura de 1500 msnm. Se obtuvieron extractos hidroalcohólicos de hojas y tallos, y fracciones a partir del extracto hidroalcohólico de hojas de A. excelsum mediante extracción por percolación. La identificación de los núcleos fitoquímicos fue realizado por cromatografía en capa delgada. La evaluación de la actividad antimicrobiana de extractos y fracciones, en concentraciones de 2, 5, 10, 20 y 40 mg/ml, frente a las 5 cepas de referencia ATCC, se realizó mediante la técnica de difusión con aplicación en pozo sobre agar Mueller-Hinton. El extracto de hojas no presentó actividad antimicrobiana sobre E. coli pero si sobre S. mutans, S. aureus, E. faecalis y C. albicans, en una concentración de 10 mg/ml, con halos de inhibición desde 9 a 11 mm, y las fracciones de acetato de etilo y acetona obtenidas del extracto de hojas de A. excelsum, presentaron mayor actividad antimicrobiana en una concentración de 10 mg/ml. En conclusión, 1. El extracto de hojas y las fracciones de acetato de etilo y acetona obtenidas del extracto de hojas de A. excelsum presentaron mayor actividad antimicrobiana sobre todos los microorganismos en estudio; 2. La evaluación de los núcleos fitoquímicos en las fracciones acetato de etilo y de acetona mostraron compuestos de tipo fenólico, taninos, terpenos del tipo triterpenos y terpenos del tipo esteroidal, que posiblemente expliquen la actividad antimicrobiana obtenida.

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Actually, bioceramic endodontic sealers represent an advantageous option for root canals sealing due to their multiple properties. There are several in vitro studies about their antimicrobial properties, however, their comparative antimicrobial potential, compared with other types of endodontic sealers is not entirely clear. The aim of the present research was to perform a systematic review to assess the antimicrobial effectiveness of commercially available bioceramic root canal sealers against Enterococcus faecalis in accordance with the PRISMA statement. A literature search was made in four electronic databases: MEDLINE, ClinicalKey, ScienceDirect and EBSCO. Were included in vitro studies, published in English, between 2015 and 2019. The evaluation of the selected studies was performed by two authors, independently. Four studies were included in the review. EndoSequence™ (Brasseler USA, Savannah, GA) also available on the market as TotalFill™ (Brasseler USA, Savannah, GA) and BioRoot™ were the bioceramic root canal sealers evaluated. The risk of bias was assessed according to the modified CONSORT checklist for preclinical studies. Selected studies reported positive antimicrobial activity against Enterococ cus faecalis in the bioceramic sealers evaluated. The less activity was observed on BioRoot™ sealer. All studies used a planktonic form of Enterococcus faecalis and in vitro laboratory methods of evaluation. The antimicrobial activity reported varies accordi ng to the laboratory method used, even for the same sealer, so the existence of false negatives is suggested. This systematic review identified the need for more research into the antimicrobial activity of bioceramic sealers, ideally with models using bacterial biofilms and studies in humans.

En la actualidad, los cementos selladores biocerámicos son una opción ventajosa para la obturación de canales radiculares debido a sus múltiples propiedades. Existen varios estudios in vitro acerca de sus propiedades antimicrobianas, sin embargo, su potencial antimicrobiano, en comparación con otros tipos de cementos selladores endodónticos, no se está completamente claro. El propósito de la presente investigación fue realizar una revisión sistemática sobre las propiedades antimicrobianas de los cementos selladores biocerámicos disponibles en el mercado sobre Enterococcus faecalis, de acuerdo a la declaración PRIS- MA. Se realizó una búsqueda bibliográfica en cuatro bases de datos electrónicas: MEDLINE, ClinicalKey, ScienceDirect y EBSCO. Se incluyeron estudios in vitro, publicados en inglés, entre 2015 y 2019. La evaluación de los estudios seleccionados fue realizada por dos autores de forma independiente. Fueron incluidos cuatro estudios en la revisión. EndoSequence™ (Brasseler USA, Savannah, GA), también comercializado en el mercado como TotalFill™ (Brasseler USA, Savannah, GA), y BioRoot™ fueron los cementos selladores biocerámicos evaluados. El riesgo de sesgo se evaluó de acuerdo con la lista de verificación CONSORT modificada para estudios preclínicos. Los estudios seleccionados informaron actividadantimicrobiana positiva contra E. faecalis en los selladores biocerámicos evaluados. La menor actividad la presentó BioRootTM. Todos los estudios utilizaron una forma planctónica de E. faecalis y métodos de evaluación in vitro. La actividad antimicrobiana reportada varió en base al método de laboratorio utilizado, incluso para el mismo sellador, por lo que se sugiere la existencia de falsos negativos. Esta revisión sistemática identificó la necesidad de realizar más investigaciones sobre la actividad antimicrobiana de los selladores biocerámicos, idealmente con modelos que utilicen biopelículas bacterianas y estudios en humanos.

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The predatory giant ant Dinoponera quadriceps is one of the largest venomous ants on Earth. The venom of D. quadriceps comprises a rich blend of bioactive peptides that includes structures related to at least five classes of antimicrobial peptides. In the present study, two representative synthetic peptides, sDq-2562 and sDq-3162, belonging to the ponericin-like dinoponeratoxin family, were evaluated for their microbicide activity against antibiotic-resistant bacteria. The most effective peptide, the 28-residue sDq-3162 displayed a significant bacteriostatic and bactericidal effect with minimal inhibitory concentrations (MICs) between 5 µM and 10 µM (15.6 µg mL-1 and 31.2 µg mL-1), according to the strain of drug-resistant bacteria tested. In combination with conventional antibiotics, sDq-3162 displayed in vitro synergistic effects, reducing the MICs of antibiotics for more than 2-log against clinical isolates of carbapenem-resistant Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa, with low cytotoxicity to human erythrocytes, in vitro. Since the development of molecules to circumvent the spread of antibiotic-resistant bacteria is demanding, ant venom peptides arise as useful molecular resources to contribute with the antimicrobial arsenal and therapeutic strategies to fight clinically relevant microbial infections.

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A necessidade da antissepsia prévia da pele para administração de injetáveis por via intradérmica, subcutânea ou intramuscular representa um procedimento polêmico. Este trabalho de atualização tem como objetivo descrever estudos que envolveram a temática, a fim de que o leitor tenha subsídios teóricos para apoiar sua prática clínica. Diante das colocações, vários questionamentos são realizados, cabendo a cada serviço de saúde estabelecer sua rotina quanto à necessidade ou não de antissepsia da pele anterior à administração de injetáveis.

The need for skin antisepsis prior to administration of intradermal, subcutaneous or intramuscular injections is a polemic topic. This update study aims to describe work on the issue, with a view to giving readers theoretical support for their clinical practice. Several queries emerged from review of the articles, and it remains to each health service to set its routine for whether or not prior skin antisepsis is needed when administering injections.

La necesidad de antisepsia previa de la piel para la administración de inyectables por vía intradérmica, subcutánea o intramuscular representa un procedimiento polémico. Este trabajo de actualización tiene como objetivo describir estudios envolviendo el tema, a fin de que el lector tenga respaldo teórico para su práctica clínica. Varios cuestionamientos surgieran a partir de las colocaciones, y cabe a cada servicio de salud establecer su necesidad o no de antisepsia de la piel anterior a la administración de inyectables.

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