Effects of a multilamellar emulsion on glucocorticoid-induced epidermal atrophy and barrier impairment.

Skin atrophy is one of the most frequent side-effects of the topical glucocorticoid. Skin barrier impairment has also been reported as a steroid-induced side effect. Although there have been various studies on preventing or minimizing this atrophogenic effect, little has been reported about preventing barrier impairment. This study was performed to determine the effects of a multilamellar emulsion (MLE) that had a well-ordered lamellar structure on the steroid-induced barrier impairment and epidermal atrophy. To confirm these effects of MLE, 0.05% clobetasol-17-propionate (CP) and 0.05% clobetasol-17-propionate in MLE (MLE/CP) were topically applied to both flanks of hairless mice for 9 days. The topically applied CP induced a significant impairment of the epidermal permeability barrier, and MLE/CP also did not have a preventive effect on this change. However, skinfold thickness studies and histological studies showed that MLE/CP significantly reduced the steroid-induced atrophy. The topical application of MLE/CP was also shown to have a preventive effect on the steroid-induced increase of the stratum corneum (SC) surface pH. In addition, the electron microscopic findings showed relatively well-conserved lamellar bilayers in the skin treated with MLE, as compared to CP only. The results showed that the topical application of MLE immediately after CP treatment prevented the glucocorticoid-induced transepidermal water loss values increase. Light microscopy measurements showed that the skin treated with MLE immediately after CP treatment for 1 week had a slightly lower decline of skin thickness than did the CP-treated skin. These results suggest that MLE should be effective for preventing glucocorticoid-induced epidermal atrophy and for repairing the barrier impairment.

Toxicity of ozonated animal manure to the house fly, Musca domestica.

Swine manure slurries were ozonated at a dosage of 1 g/L and tested for their toxicity to the house fly (Musca domestica). The observed toxicity of ozonated swine manure was consistent and independent of origin of the swine manure. A dose (dilution) response curve was performed. A 50% dilution in the ozonated swine manure slurry resulted in 90% reduction in toxicity. Neither the synthetic nor ozonated synthetic swine manure, both of which contained higher concentrations of formaldehyde and three other unidentified carbonyl compounds than the ozonated swine manure, were toxic to the flies. Ozonated swine manure slurry was centrifuged and passed through a 0.45-microm filter. The liquid phase was as toxic as the unfiltered slurry; as such, the toxicant appears to be present in liquid phase. Neither ammonia, hydrogen sulfide, formaldehyde, nor other simple aldehydes appeared to be the toxic agent. The toxic agent appears to be a polar chemical compound and is concentrated in the urine. Several possible compounds have been identified. The toxicity of untreated and ozonated manure slurries from different livestock was compared. Six animal manure slurries (beef and dairy cattle, horse, poultry, sheep, and swine) were ozonated (dosage of 1 g/L) and tested for toxicity to the house fly. Ozonated dairy cattle manure slurry showed 78% mortality after 72 h, whereas ozonated swine manure slurry achieved a 100% mortality rate in 48 h. Neither the unozonated dairy nor swine manure slurries, nor any of the other raw or ozonated manure slurries, were toxic to the flies.