Quantitative analysis of the effects of antimycotic agents on the hyphal growth of Trichophyton rubrum: a preliminary study.
The thallus diameter is commonly used as a quantitative parameter to evaluate hyphal growth. However, a different parameter is required to evaluate hyphal growth more precisely. The hyphal growth of Trichophyton rubrum in the presence of antimycotic agents was evaluated using the number of hyphal crossings as a quantitative parameter. Continuous video images of hyphal growth were taken for 48 h. Culture medium contained 0.4 μg ml(-1) of terbinafine (TBF) and itraconazole (ITCZ). Image analyses were performed every 6 h using a 50 μm square grid. The mean density of the hyphal crossings in each sampling frame was used as a parameter of hyphal growth. The mean ratio of hyphal crossings on distressed hyphae to total hyphal crossings was used as a parameter representing the antimycotic effects of TBF and ITCZ. The mean density of total hyphal crossings in the TBF group was significantly lower than in the control and ITCZ groups. The ratio of distressed hyphae significantly increased during the 48-h time course in the TBF group, but not in the ITCZ group. Counting the number of hyphal crossings provides a new method for assessing hyphal growth and antimycotic activity quantitatively.
Hatta
Junko
J
Department of Dermatology, Kanazawa Medical University, Ishikawa, Japan.
Hatta
Toshihisa
T
Miyagawa
Susumu
S
Kitahara
Yukio
Y
Hirota
Tsuyoshi
T
Anzawa
Kazushi
K
Mochizuki
Takashi
T
D000935:Antifungal Agents / Q000494:pharmacology*; D003470:Culture Media / Q000737:chemistry; D006801:Humans; D025301:Hyphae / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development*; D017964:Itraconazole / Q000494:pharmacology; D008826:Microbial Sensitivity Tests / Q000379:methods; D018715:Microscopy, Video / Q000379:methods; D009281:Naphthalenes / Q000494:pharmacology; D000077291:Terbinafine; D013997:Time Factors; D014249:Trichophyton / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development*
D000935:Antifungal Agents; D003470:Culture Media; D009281:Naphthalenes; D017964:Itraconazole; D000077291:Terbinafine