D. Yang et al., A NEW SIMULATION-MODEL TO STUDY THE TOPIC PENETRATION OF ANTIFUNGAL DRUGS IN HARD KERATIN IN-VITRO, Journal de mycologie medicale, 7(4), 1997, pp. 195-198
The topic treatments of onychomycosis are often inefficient because of
the bad penetration of antifungal agents into hard keratin. We have m
odelled a simulation protocol on sheep hoof plates, sufficiently simil
ar to human nail both in the structure showed by Scanning Electron Mic
roscope and the absorption of chemical molecules. In sterile medium, t
he dermatophyte was put on the internal face of the hoof plates, the l
atter received the antifungal preparation on the other face. Three dif
ferent protocols were envisaged: antifungal pre-treatment of 4 days, f
ollowed by dermatophytic inoculation, timely application of dermatophy
te and antifungal medicine, antifungal treatment on the infected sheep
hoofs after 5 days at least. The latest modelling was the closest to
the topic therapy of mycosic onyxis. The results showed that more fung
us was attacked precociously, shorter the treatment lime was. The four
antifungal products: amorolfine, ciclopirox, ciclopiroxolamine and su
lconazole, penetrated well through the hoof plates, but they could not
completely inhibit the development of dermatophytes after 10 days of
treatment in vitro. This technic very cheap and easy to realize, permi
ts to compare and to predict in vitro the efficacy of different formul
ations or galenic forms intended for onychomycosis treatment.