Fig. 9
From: A quantitative model for dermal infection and oedema in BALB/c mice pinna
Effect of a standard treatment on the model of dermal infection and oedema. We analyze the effect of an otic formulation made with Ciprofloxacin as antibacterial and Hydrocortisone, Benzocaine as anti-inflammatory treatment on a dermal infection induced by S. pyogenes, The bacterium was inoculated in both pinna of 12 mice as previously mentioned, and the treatment was assessment in comparison with a placebo. Two kind of application were evaluated: as a curative (24 h post inoculation) or preventive (1 h post-inoculation). Treatments were applied in a blind way but considering that one infected pinna was exposed to the standard treatment and the contralateral was treated with a placebo (glycerol 50%). a Antibacterial effect of curative treatment applied 24 h post inoculation, S. pyogenes could resist the first 5 days of the treatment with the ciprofloxacin in the standard formulation, we found statistical difference only from the 5 to 6 day of treatment in comparison with placebo (p <0.034, x 2 test). b Antibacterial effect of preventive treatment, when the standard formulation was applied 1 h post inoculation, we could observe that S. pyogenes was not able to survive more than 2 days in presence of the antibiotic, we found statistical significant difference during the first 5 days (p <0.0285, x 2 test). c Anti-inflammatory effect of the curative treatment. 24 h after inoculation, S. pyogenes caused an increase of the ear thickness that represent 100%, when applied the formulation with hydrocortisone as standard anti-inflammatory drug, we found a decrease in the ear thickness that was statistically significant with the placebo during the first 3 days (p <0.026, paired t student test). d Anti-inflammatory effect of the preventive treatment. 1 h after inoculation of S. pyogenes, the pinna were treated with the formulation, we found that standard anti-inflammatory drugs was able to prevent the increase in thickness observed in placebo-treated pinna, the difference was significant during the first 3 days (p <0.0032, paired t student test)