ABSTRACT
Aims@#Phytochemical analysis showed Orthosiphon stamineus (OS) possessed bioactive compounds with antiviral properties against Herpes Simplex Virus Type 1 (HSV-1). However, there isn’t any study reported so far on OS virucidal properties towards HSV-1. Thus, this study aims to investigate virucidal mechanism of OS aqueous extract that possibly acts as a potent entry inhibitor against HSV-1 infection. @*Methodology and results@#Virucidal attachment and penetration assays were done via plaque assay to investigate the virucidal anti-HSV-1 mechanism of OS. The aqueous extract of OS leaves (OSA) was found to reduce HSV-1 plaques in virucidal assays. Inhibitory effect by OSA was observed as early as 30 min after exposing OSA to HSV-1 in a concentration-dependent manner suggesting a direct anti-HSV-1 property of OSA. Further investigation of the stages in which OSA inhibits HSV-1 shows virions treated with OSA failed to attach onto the host cell which implicated a role of OSA in blocking HSV-1 attachment to its host. OSA was also found to reduce HSV-1 plaques in penetration assay. Further evaluation using transmission electron microscopy (TEM) on OSA treated virion showed defective HSV-1 virion without envelope and the remaining capsid was altered. @*Conclusion, significance and impact of study@#These findings concluded that Orthosiphon stamineus leaves extract have virucidal activity by disintegrating HSV-1 virion structure and interfering with the attachment and penetration of the virus into the host cell. Thus, through the new mechanism against HSV-1, OS has the potential to be further developed as an anti-HSV-1 agent.
ABSTRACT
Purpose: Antiseptic mouthrinses containing chlorhexidine (CHX) seem to be the most effective chemical agents for plaque control. The CHX concentration is usually 0.12% or 0.20%, but formulations with lower concentrations of CHX (0.05%) in combination with other active agents such as sodium fluoride (0.05%) or cetyl pyridinium chloride (0.05%) (Cpc) are available. The aim of this study was to compare plaque formation at 24 hours after the use of 0.1% CHX mouthrinse-gel and mouthrinses containing 0.12% and 0.05% CHX plus other active agents. Methods: A controlled, randomized, double-blind, crossover clinical trial was designed. Thirty subjects underwent four consecutive experimental phases with four treatments: CHX 0.1% + hydroxymethylcellulose 2.5% (HMC), CHX 0.12% + alcohol, CHX 0.12% + 0.05% sodium fluoride, and CHX 0.05% + 0.05% Cpc. On the day of study, the subjects discontinued all other oral hygiene habits and were randomly assigned for treatment with the experimental mouthwash. Each experimental phase was preceded by a 28-day washout period. Plaque formation was recorded after one undisturbed day. Results: Formulations of CHX 0.12% with alcohol and sodium fluoride and CHX 0.1% + HMC 2.5% reduced de novo plaque formation to a greater extent than the mouthwash with CHX 0.05% + Cpc (P < 0.05). Conclusion: The 0.1% CHX gel presents an anti-plaque efficacy similar to that of mouthwashes containing 0.12% CHX and other active agents, and was more effective at inhibiting plaque formation than the mouthwash containing 0.05% CHX with Cpc.
Objetivo: Enxaguatórios contendo clorexidina (CHX) parecem ser os mais eficazes agentes químicos para controle de placa. A concentração de CHX geralmente é de 0.12% ou 0.20%, mas formulações de clorexidina em concentrações mais baixas (0.05%) com outros agentes ativos, tais como fluoreto de sódio (0.05%), cloreto de cetilpiridínio (0.05%) estão disponíveis atualmente. Este estudo teve por objetivo comparar a eficácia de gel de clorexidina a 0.1% com enxaguatórios contendo 0.12% e 0.05% CHX e outros agentes ativos, em relação ao crescimento de placa bacteriana em 24 horas. Metodologia: Um ensaio clínico com delineamento cruzado, randomizado, controlado e duplo-cego foi concebido. Trinta sujeitos foram submetidos a quatro fases experimentais consecutivas com quatro tratamentos (bochechos): CHX 0.1% + HMC 2.5%, 0.12% CHX + álcool, CHX 0.12% + 0.05% de fluoreto de sódio e CHX 0.05% + 0.05% cloreto de cetilpiridínio. No dia de estudo, os indivíduos interromperam todas as medidas de higiene oral e foram tratados os bochechos experimentais aleatoriamente. Cada fase experimental foi precedida por um período de 28 dias de washout. A formação de placa foi registrada depois de um dia sem disturbio de formação. Resultados: As formulações de CHX 0.12% com álcool e fluoreto de sódio e gel foram eficientes em retardar a formação de placa e foram superiores (P < 0,05) para a CHX 0.05% com cloreto de cetilpiridínio. Conclusão: O gel de clorexidina 0,1% para bochechos apresenta uma eficácia antiplaca semelhante aos bochechos de 0.12% CHX com outros agentes ativos, sendo superior aos bochechos de clorexidina a 0.05% com cloreto de cetilpiridínio.