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AIM: The main objective of the study was to develop and validate a model for the growth of Aspergillus brasiliensis on surfaces, specifically on agar culture medium. An additional aim was to determine conditions for complete growth inhibition of this micromycete using two different nonthermal plasma (NTP) sources. METHODS AND RESULTS: The developed model uses two key parameters, namely the growth rate and growth delay, which depend on the cultivation temperature and the amount of inoculum. These parameters well describe the growth of A. brasiliensis and the effect of NTP on it. For complete fungus inactivation, a single 10-minute exposure to a diffuse coplanar surface barrier discharge was sufficient, while a point-to-ring corona discharge required several repeated 10-minute exposures at 24-h intervals. CONCLUSIONS: The article presents a model for simulating the surface growth of A. brasiliensis and evaluates the effectiveness of two NTP sources in deactivating fungi on agar media.

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Objective: The aim of this study was to compare the bond strength of High-Translucency zirconia (HT) and lithium disilicate dental ceramics, under different surface treatments. Material And Methods: For this, ceramics were divided into groups: Control Group (C) (n = 5), lithium disilicate sheets, conditioned with 10% hydrofluoric acid, followed by application of 37% phosphoric acid, silane and universal adhesive application; Group HTAI (n = 5), HT zirconia sheets were blasted with silica oxide, followed by the application of universal adhesive; Group HTPAI (n = 5), HT zirconia sheets were blasted with silica oxide, followed by the application of non-thermal plasma and universal adhesive and the HTP Group (n = 5), HT zirconia received only the application of non-thermal argon plasma. Subsequently, the specimens of each group were subjected to a cementation process with resin cement, obtaining cylinders. After 24 h of storage, in distilled water, at 37°C, the specimens were subjected to a mechanical micro-shear test. The data obtained were submitted to ANOVA One-way followed by the Tukey test (5%). Results: The HTP Group was excluded from the statistical analysis, as adhesions failed within the storage period. In addition, it was not possible to verify a statistical difference between the control group C and the experimental groups HTAI and HTPAI. Conclusion: The results showed that the applicability of high translucency zirconia can potentially be compared to the lithium disilicate bond strength, when submitted to the same surface treatments, except for the plasma application, which alone was not effective (AU)

Objetivo: O objetivo deste estudo foi comparar a resistência adesiva das cerâmicas dentárias de zircônia de alta translucidez e dissilicato de lítio. Materiais e Métodos: Para isso, cerâmicas foram divididas em grupos: Grupo Controle (C) (n = 5), lâminas de dissilicato de lítio, condicionadas com ácido fluorídrico 10%, seguido de aplicação do ácido fosfórico 37%, aplicação de silano e aplicação do adesivo universal; Grupo HTAI (n = 5), lâminas de zircônia HT foram submetidas ao jateamento com óxido de sílica, seguido da aplicação do adesivo universal; Grupo HTPAI (n = 5), lâminas de zircônia HT foram submetidas ao jateamento com óxido de sílica, seguido da aplicação do plasma não térmico e do adesivo universal e o Grupo HTP (n = 5), lâminas de zircônia HT receberam apenas a aplicação do plasma não térmico de argônio. Posteriormente, os espécimes de cada grupo foram submetidos a um processo de cimentação com cimento resinoso, obtendo-se cilindros. Após 24h, de armazenamento em água destilada a 37°C, os espécimes foram submetidos a ensaio mecânico de microcisalhamento. Os dados obtidos foram submetidos à ANOVA 1-fator seguido pelo teste de Tukey (5%). Resultados: O Grupo HTP foi descartado da análise estatística, pois as adesões falharam dentro do período de armazenamento. Além disso, não foi possível verificar diferença estatística entre o grupo controle C e os experimentais HTAI e HTPAI. Conclusão: Os resultados mostraram que a aplicabilidade das zircônias de alta translucidez pode potencialmente ser comparada à resistência adesiva da cerâmica de dissilicato de lítio, quando submetidas aos mesmos tratamentos de superfície, com exceção da aplicação de plasma, que isoladamente não foi efetiva (AU)

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PURPOSE: Herpes keratitis (HK) is the leading cause of cornea-derived and infection-associated blindness in the developed world. Despite the availability of effective antivirals, some patients develop refractory disease, drug-resistant infection, and topical toxicity. A nonpharmaceutical treatment modality may offer a unique advantage in the management of such cases. This study investigated the antiviral effect of nonthermal dielectric barrier discharge (DBD) plasma, a partially ionized gas that can be applied to organic substances to produce various biological effects. METHODS: Human corneal epithelial cells and explanted corneas were infected with herpes simplex virus type 1 (HSV-1) and exposed to culture medium treated with nonthermal DBD plasma. The extent of infection was measured by plaque assay, quantitative PCR, and Western blot. Corneal toxicity assessment was performed with fluorescein staining, histologic examination, and 8-OHdG detection. RESULTS: Application of DBD plasma-treated medium to human corneal epithelial cells and explanted corneas produced a dose-dependent reduction of the cytopathic effect, viral genome replication, and the overall production of infectious viral progeny. Toxicity studies showed lack of detrimental effects in explanted human corneas. CONCLUSIONS: Nonthermal DBD plasma substantially suppresses corneal HSV-1 infection in vitro and ex vivo without causing pronounced toxicity. TRANSLATIONAL RELEVANCE: Nonthermal plasma is a versatile tool that holds great biomedical potential for ophthalmology, where it is being investigated for wound healing and sterilization and is already in use for ocular microsurgery. The anti-HSV-1 activity of DBD plasma demonstrated here could be directly translated to the clinic for use against drug-resistant herpes keratitis.