Comparative antimicrobial activity of four different endodontic sealers.

Dental cements are widely used in the clinical routine, specifically for root canal sealing. Within this context, it is expected that these materials present antimicrobial activity, since it would help in the prevention of apical and periapical infections. The present study aimed to comparatively verify the antimicrobial activity of four dental cements against microorganisms that are routinely isolated from endodontic infections. Reference strains of Enterococcus faecalis, Candida albicans and Escherichia coli were submitted to the agar diffusion test and to modified direct contact test using four different sealers: an eugenol zinc oxide compound, an epoxy resin associated to calcium hydroxide and bismuth, a mineral trioxide aggregate (MTA) and a bioceramics. Different E. coli, C. albicans and E. faecalis growth inhibition profiles were observed in the agar diffusion assay. In the direct contact test, the bioceramics presented a higher microbicide activity on all microorganisms tested herein. Dental cements have different antimicrobial activities, being that the bioceramics present the most consistent antimicrobial activity, and that the direct contact test presented more uniform results than the agar diffusion test. This study reveals the antimicrobial activities of different cements and allow dentists to decide which material to employ in their daily practice.

Photodynamic inactivation of different Candida species and inhibition of biofilm formation induced by water-soluble porphyrins.

BACKGROUND: Candida spp. is the main fungal genus related to infections in humans, and its treatment has become a challenge due to the production of biofilm and its resistance/multi-resistance profile to conventional antifungals. Antimicrobial photodynamic therapy stands out as a treatment characterized by a broad spectrum of antimicrobial action, being able to induce oxidative stress in pathogens, and porphyrins are photosensitizers with high selectivity to pathogens. Thus, this work aimed to analyze the photoinactivation of different species of Candida by two cationic (4-H2TMeP+ and 3-H2TMeP+) and one anionic (4-H2TPSP‒) porphyrins. MATERIALS AND METHODS: Microdilution assays were performed to determine the MIC100, with subsequent determination of MFC100. Determination of oxidative species was done through the use of scavengers, while biofilm morphological features were investigated using the atomic force microscopy. RESULTS: Cationic porphyrins were significantly efficient in inactivating Candida albicans and non-albicans species with 100% growth inhibition and fungicidal activity (MFC100/MIC100 ≤ 4.0). The cationic porphyrins were also able to interfere in Candida spp biofilm formation. The photo-oxidative mechanism activated by 3-H2TMeP+ in Candida spp. is concurrent with the production of singlet oxygen and oxygen radical species. In the AFM analysis, 3-H2TMeP+ was able to reduce yeast adhesion to the surface. CONCLUSIONS: Cationic porphyrins can photo-inactivate different species of Candida in both planktonic and biofilm-associated forms, and reduce the adhesion of these fungi to the surface.

Perfil de sensibilidade a antibióticos de um isolado de Providencia rettgeri proveniente de equino / Antibiotic sensitivity profile in isolate of Providencia rettgeri from a horse

Introdução: a meningite bacteriana em equinos é uma enfermidade frequente em animais jovens. Streptococcus spp., Staphylococcus aureus e Escherichia coli são as bactérias mais comumente isoladas nesses casos. Apesar da bactéria Providencia rettgeri já ter sido isolada em casos de meningite humana e de crocodilo, não há relatos de seu isolamento em equinos. Objetivo: relatar o isolamento e a identificação da bactéria P. rettgeri de um potro com sintomas neurológicos e avaliar o perfil de sensibilidade a antibióticos deste isolado. Metodologia: o isolamento foi realizado a partir do líquido cefalorraquidiano do potro, por meio de cultivo em meio ágar chocolate. Após isolamento, as colônias formadas foram identificadas por equipamento Biotyper, baseado em espectrometria de massa. O perfil de sensibilidade foi definido por teste de difusão em discos, seguindo metodologia relatada pelo CLSI M2-A8 em 2003, sendo a bactéria classificada como resistente, padrão indeterminado ou sensível aos antibióticos, de acordo com o descrito pelo EUCAST em 2021. Resultados: este é o primeiro relato do isolamento de P. rettgeri como agente etiológico de meningite em potro. Dos 15 antibióticos testados, a bactéria foi resistente a 9, sensível a 5 e com padrão indeterminado a 1 antibiótico. Conclusão: nossos resultados indicam que P. rettgeri deve ser considerada entre possíveis agentes etiológicos de quadros neurológicos em equinos e que testes de sensibilidade a antibiótico são fundamentais, uma vez que essa bactéria já apresenta resistência a diversos antibióticos disponíveis comercialmente.

Introduction: Bacterial meningitis in horses is a frequent disease in young animals. Streptococcus spp., Staphylococcus aureus and Escherichia coli are the most commonly isolated bacteria in these cases. Although Providencia rettgeri bacterium has already been isolated in cases of human and crocodile meningitis, there are no reports of its isolation in cases of meningitis in horses. Objective: to report isolation and identification of the P. rettgeri bacteria from a foal with neurological symptoms and to assess antibiotic sensitivity profile in isolate of it. Methods: isolation was performed from the foal's cerebrospinal fluid, through cultivation in chocolate agar medium. After isolation, formed colonies were identified by Biotyper equipment, based on mass spectrometry. Sensitivity profile was verified by disk diffusion test, according to methodology that was reported by CLSI M2-A8 in 2003, which classified bacteria as resistant, indeterminate pattern or sensitive to antibiotics, as described by EUCAST in 2021. Results: this is the first report on isolation of P. rettgeri as an etiologic agent of meningitis in foals. Among 15 antibiotics that were tested, results showed bacteria resistence to 9 antibiotics, bacteria sensitivity to 5, but undetermined pattern to 1 antibiotic. Conclusion: results indicate that P. rettgeri shall be considered among potential etiologic agents of neurological conditions in horses and that antibiotic sensitivity tests are essential, since this type of bacterium is already resistant to several commercially available antibiotics.

Non-marine invasive gastropods on Ilha Grande (Angra dos Reis, Rio de Janeiro, Brazil): distribution and implications for conservation / Moluscos continentais invasores na Ilha Grande (Angra dos Reis, Rio de Janeiro, Brasil): distribuição e implicação para a conservação

Abstract Invasive species are one of the main causes of biodiversity loss and the knowledge of their distribution is essential for conservation efforts. The present study inventoried the land and freshwater invasive molluscs of 25 villages of Ilha Grande (Rio de Janeiro, Brazil), an island with Atlantic Rainforest remnants. Three invasive species are found: Melanoides tuberculata (Müller, 1774), Physa acuta Draparnaud, 1805, both on two localities; and Achatina fulica Bowdich, 1822, on 16 localities. Most records were done on the island continental side, in anthropic areas, probably due to ease of access. One record was inside a conservation area, that calls concern about the spread of those species on the island and possible effects.

Resumo As espécies invasoras são uma das maiores causas de perda de biodiversidade e o conhecimento acerca da sua distribuição é essencial para os esforços de conservação. O presente estudo inventariou os moluscos continentais invasores em 25 vilas da Ilha Grande (Rio de Janeiro, Brasil), uma ilha com remanescentes de Mata Atlântica. Três espécies invasoras foram encontradas: Melanoides tuberculata (Müller, 1774), Physa acuta Draparnaud, 1805, ambas em duas localidades; e Achatina fulica Bowdich, 1822, em 16 localidades. A maior parte dos registros foi no lado continental da ilha, provavelmente devido a facilidade de acesso. Um dos registros foi dentro de uma área de conservação, o que chama a atenção para a dispersão destas espécies na ilha, e seus possíveis efeitos.

Freshwater mollusks and environmental assessment of Guandu River, Rio de Janeiro, Brazil / Moluscos de água doce e avaliação ambiental do rio Guandu, Rio de Janeiro, Brasil

Abstract The Guandu River Basin is extremely important to state of Rio de Janeiro, as a water supplier of several municipalities. However, the malacological knowledge and environmental status is not well known to this basin. The aim of this paper is to present an inventory of freshwater mollusks, as well as an environmental assessment through a Rapid Assessment Protocol, of ten sampling sites at Guandu River basin in six municipalities (Piraí, Paracambi, Japeri, Seropédica, Queimados and Nova Iguaçu). Thirteen species of molusks were found, eight native (Pomacea maculata, Biomphalaria tenagophila, Gundlachia ticaga, Gundlachia radiata, Omalonyx matheroni, Diplodon ellipticus, Anodontites trapesialis and Eupera bahiensis) and five exotics (Melanoides tuberculata, Ferrissia fragilis, Physa acuta, Corbicula fluminea and Corbicula largillierti). The environmental analysis ranked most sites as "modified". The expansion of exotic species with their associated negative effects, as well the gap in knowledge of native species calls attention to the need of future studies of biology and ecology of the species found.

Resumo A bacia do rio Guandu é de extrema importância para o estado do Rio de Janeiro, pois abastece grande parte da região metropolitana. Contudo, aspectos malacológicos e ambientais desta bacia são pouco conhecidos. O presente trabalho teve por objetivo realizar um inventário das espécies de moluscos de água doce ocorrentes na região, assim como uma avaliação ambiental através de um Protocolo de Avaliação Rápida, de dez estações de coleta na bacia do rio Guandu em seis municípios (Piraí, Paracambi, Japeri, Seropédica, Queimados e Nova Iguaçu). Foram encontradas 13 espécies, sendo oito nativas (Pomacea maculata, Biomphalaria tenagophila, Gundlachia ticaga, Gundlachia radiata, Omalonyx matheroni, Diplodon ellipticus, Anodontites trapesialis e Eupera bahiensis) e cinco exóticas (Melanoides tuberculata, Ferrissia fragilis, Physa acuta, Corbicula fluminea e Corbicula largillierti). A avaliação ambiental caracterizou a maior parte das estações de coleta como "modificado". A dispersão das espécies exóticas e os efeitos negativos a elas associados, além da nossa falta de conhecimento sobre as espécies nativas chama a atenção para a necessidade de futuros estudos biológicos e ecológicos das espécies encontradas.

First record of Melanoides tuberculatus (Müller, 1774) and Biomphalaria tenagophila (dïOrbigny, 1835) on Ilha Grande, Rio de Janeiro, Brazil / Primeiro registro de Melanoides tuberculatus (Müller, 1774) e Biomphalaria tenagophila (d´Orbigny, 1835) para a Ilha Grande, Rio de Janeiro, Brasil

Small populations of Melanoides tuberculatus (Müller, 1774) and Biomphalaria tenagophila (dïOrbigny, 1835), were found at Vila do Abraão, being the first record of these species to Ilha Grande, Angra dos Reis, Rio de Janeiro. They were probably introduced after 2004, perhaps following release from aquaria. The possible spread of these species to other freshwater habitats in the island, their effects on native snails and links with public health are discussed. The record of M. tuberculatus appears to be the first for a Brazilian insular area. The recent introduction of these species offers a remarkable opportunity to monitor introduced species and to understand the invasion process in an insular stream in southeastern Brazil.

Pequenas populações de Melanoides tuberculatus (Müller, 1774) e de Biomphalaria tenagophila (dïOrbigny, 1835) foram encontradas na Vila do Abraão, sendo este o primeiro registro dessas espécies para a Ilha Grande, Angra dos Reis, Rio de Janeiro. A introdução provavelmente ocorreu após 2004, como conseqüência do despejo de água de aquário. A possível dispersão destas espécies para outros corpos dïágua, efeitos sobre as espécies nativas e conseqüências para saúde pública são tópicos discutidos. Em relação a M. tuberculatus, este é o primeiro registro para uma área insular do Brasil. A introdução recente destas espécies oferece uma oportunidade única para o monitoramento de espécies introduzidas e para uma melhor compreensão do processo de invasão, especialmente de M. tuberculatus, em córrego insular do sudeste do Brasil.