RESUMO
Organic acid and essential oils (EOs), well-known antimicrobials, could also possess antiviral activity, a characteristic which has not been completely addressed up to now. In this study, the effect of two organic acids (formic acid and sodium salt of coconut fatty acid distillates) and two single EO compounds (thymol and cinnamaldehye) was evaluated against porcine epidemic diarrhea virus (PEDV). The concentration used for each compound was established by cytotoxicity assays in Vero cells. The antiviral activity was then evaluated at three multiplicities of infection (MOIs) through visual cytopathic effect (CPE) evaluation and an alamarBlue assay as well as real-time reverse-transcription PCR (RT-qPCR) and viral titration of cell supernatants. Formic acid at at a dose of 1,200 ppm was the only compound which showed antiviral activity, with a weak reduction of CPE caused by PEDV. Through the alamarBlue fluorescence assay, we showed a significant anti-CPE effect of formic acid which could not be observed by using an inverted optical microscope. RT-qPCR and infectivity analysis also showed that formic acid significantly reduced viral RNA and viral titers in a PEDV MOI-dependent manner. Our results suggest that the antiviral activity of formic acid could be associated to its inhibitory effect on viral replication. Further studies are required to explore the anti-PEDV activity of formic acid under field conditions alone or together with other antiviral agents.
RESUMO
PURPOSE: There is a large number of publications evaluating neuromuscular risk factors for anterior cruciate ligament (ACL) injury in athletes. However, most of them have involved the female athlete and, in addition, the gastrocnemius muscles have been less investigated by far compared with the quadriceps and hamstring. The purpose of this study was to investigate the role of the gastrocnemius muscles as neuromuscular risk factors for ACL injury in male soccer players, through tensiomyography (TMG). METHODS: All competitive male soccer players with confirmed ACL tear included in this study underwent resting TMG assessment of gastrocnemius medialis (GM) and gastrocnemius lateralis muscles of the uninjured side. The same values were obtained from a sex-, and sports level-matched control group in both sides. The maximal displacement (D m), delay time (T d), contraction time (T c), sustained time (T s), and half-relaxation time (T r) were obtained for both muscles. TMG values of the uninjured side in ACL-injured group were compared with the mean values between both sides in the control subjects. RESULTS: There were no significant between-group differences in demographic characteristics. Most TMG parameters of the gastrocnemius muscles were not significantly different between the two groups. Only the GM-T r (p = 0.02) and GM-D m (p = 0.006) were significantly higher in the ACL-injured group compared with control group. CONCLUSIONS: Neuromuscular characteristics in terms of mechanical and contractile properties of the gastrocnemius muscles may not be significant risk factors for ACL injury in male soccer players.
