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Staphylococcus aureus is able to rapidly develop mechanisms of resistance to various drugs and to form strong biofilms, which makes it necessary to develop new antibacterial drugs. The essential oil of Melaleuca alternifolia is used as an antibacterial, a property believed to be mainly due to the presence of terpinen-4-ol. Based on this, the objective of this study was to evaluate the antibacterial and antibiofilm potential of terpinen-4-ol against S. aureus. The Minimal Inhibitory and Minimal Bactericidal Concentrations (MIC and MBC) of terpinen-4-ol were determined, and the effect of its combination with antibacterial drugs as well as its activity against S. aureus biofilms were evaluated. In addition, an in silico analysis of its pharmacokinetic parameters and a molecular docking analysis were performed. Terpinen-4-ol presented a MIC of 0.25% (v/v) and an MBC of 0.5% (v/v) (bactericidal action); its association with antibacterials was also effective. Terpinen-4-ol has good antibiofilm activity, and the in silico results indicated adequate absorption and distribution of the molecule in vivo. Molecular docking indicated that penicillin-binding protein 2a is a possible target of terpinen-4-ol in S. aureus. This work highlights the good potential of terpinen-4-ol as an antibacterial product and provides support for future pharmacological studies of this molecule, aiming at its therapeutic application.

The increase in Staphylococcus aureus resistance to conventional antibacterials and persistent infections related to biofilms, as well as the low availability of new antibacterial drugs, has made the development of new therapeutic alternatives necessary. Medicinal plants are one of the main sources of bioactive molecules and myrtenol is a natural product with several biological activities, although its antimicrobial activity is little explored. Based on this, the objective of this study was to evaluate the antibacterial activity of myrtenol against S. aureus, determining the minimum inhibitory and bactericidal concentrations (MIC and MBC), investigating the possible molecular target through the analysis of molecular docking. It also aimed to evaluate the effect of its combination with antibacterial drugs and its activity against S. aureus biofilms, in addition to performing an in silico analysis of its pharmacokinetic parameters. Myrtenol showed MIC and MBC of 128 µg/mL (bactericidal action) and probably acts by interfering with the synthesis of the bacterial cell wall. The effects of the association with antibacterials demonstrate favorable results. Myrtenol has remarkable antibiofilm activity and in silico results indicate a good pharmacokinetic profile, which make myrtenol a potential drug candidate for the treatment of infections caused by S. aureus.

This work describes the synthesis of spiro 1,3,4‐thiadiazolines from isatin‐β‐thiosemicarbazone acetylation, using microwave irradiation as a source of heating the reaction medium. N‐substituted isatin derivatives were used as substrates to obtain thiosemicarbazones by adding thiosemicarbazide to the isatin ketone carbonyl. The final synthetic step was the reaction of thiosemicarbazones with acetic anhydride under microwave irradiation to get the spiro compounds. Reaction times ranged from 6 to 18 minutes resulting in yields of up to 90%. Biological assays have shown promising antibacterial and antifungal activity, especially spiro thiadiazolines derived from allylated isatins. All the proposed molecules proved to be potential drug candidates based on the results of the in silico investigation, with satisfactory drug‐likeness and drug‐score, respecting Lipinski's rule. The use of the microwave reactor was efficient for the synthesis of thiosemicarbazones and spiro compounds, resulting in a significant reduction in reaction times with conventional heating. Taking into account the threat of antimicrobial resistance, this work presents a series of bioactive molecules that are easily obtained via microwave reaction.

The enantiomers (R)-(+)-β-citronellol and (S)-(−)-β-citronellol are present in many medicinal plants, but little is understood about their bioactivity against Candida yeasts. This study aimed to evaluate the behavior of positive and negative enantiomers of β-citronellol on strains of Candida albicans and C. tropicalis involved in candidemia. The minimum inhibitory concentration (MIC) and minimum fungicide concentration (MFC) were determined. The evaluation of growth kinetics, mechanism of action, and association studies with Amphotericin B (AB) using the checkerboard method was also performed. R-(+)-β-citronellol and S-(−)-β-citronellol presented a MIC50% of 64 µg/mL and a MFC50% of 256 µg/mL for C. albicans strains. For C. tropicalis, the isomers exhibited a MIC50% of 256 µg/mL and a MFC50% of 1024 µg/mL. In the mechanism of action assay, both substances displayed an effect on the fungal membrane but not on the fungal cell wall. Synergism and indifference were observed in the association of R-(+)-β-citronellol and AB, while the association between S-(−)-β-citronellol and AB displayed synergism, additivity, and indifference. In conclusion, both isomers of β-citronellol presented a similar profile of antifungal activity. Hence, they can be contemplated in the development of new antifungal drugs providing that further research is conducted about their pharmacology and toxicity.

A Doença de Chagas (DC) é uma infecção parasitária que acomete milhões de indivíduos no mundo, principalmente, os que vivem em países marcados pela pobreza. Levando em conta a dimensão desta doença negligenciada. Assim, o presente estudo tem por objetivo avaliar variáveis associadas a morbidade hospitalar por DC na região Nordeste do Brasil. Para isso, foram utilizados os dados armazenados no Sistema de Informações Hospitalares do SUS (SIH/SUS), referente ao número de internações e de óbitos, taxa de mortalidade hospitalar, valor médio por internação e valor total das internações, regime, caráter de atendimento, sexo e cor/raça, considerando a população do Nordeste, no período de 2008 a 2018. Os dados obtidos apontaram que os anos de 2008 e 2011 foram, respectivamente, os anos de maior e menor registros de internações. No entanto, 2008 deteve a taxa de mortalidade hospitalar mais baixa. Considerando todo o período, foram gastos US$ 1.272.109,80 em internações, o que equivale a um valor médio por internação de US$ 675,20. A maior parte das internações foram realizadas no sistema público de saúde, além de serem de caráter de urgência. Também se verificou que o sexo masculino apresentou maiores registros em todas as variáveis quando comparados com o sexo feminino. Ademais, a cor parda foi predominante em relação às demais. Dessa maneira, pode-se perceber um alto investimento para tratamento de pessoas acometidas com doenças de chagas que vem reduzindo ao longo dos anos, associado também a redução do número de internações hospitalares, e aumento da taxa de mortalidade.

<p><strong>Introdução</strong>: aloe vera é uma planta medicinal que apresenta diversas propriedades biológicas, dentre elas atividade cicatrizante.<br /><strong>Objetivo</strong>: realizar uma revisão de literatura com o intuito de observar a atividade pró-cicatrizante de A. vera em diferentes formas<br />farmacêuticas. <strong>Metodologia</strong>: trata-se de uma revisão de literatura do tipo integrativa, realizada nas bases de dados Lilacs e SciElo.<br /><strong>Resultados</strong>: dentre os 115 estudos encontrados, somente 7 artigos, publicados entre os anos de 1999 a 2018, foram utilizados para<br />a construção dos resultados. A. vera apresentou atividade cicatrizante em modelos humanos e animais, sendo a forma farmacêutica<br />gel a mais utilizada (42,8%), seguida de extratos (28,6%). A atividade cicatrizante pode estar associada a presença de polissacarídeos<br />que atuam diretamente sobre fibroblastos contribuindo para o processo de cicatrização. <strong>Conclusão</strong>: a. vera em géis, extratos,<br />unguento e nanopartículas demonstrou apresentar não somente atividade cicatrizante, mas também relacionada a inibição de<br />processos inflamatórios.</p>

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