RESUMO
BACKGROUND: Variations occur in the pH of cutaneous wounds which may affect wound closure, graft take and microbial infection rates. OBJECTIVES: To determine how pH modulates cell behaviour in order to optimize wound care. METHODS: The effects of pH on the attachment, proliferation and migration of keratinocytes and fibroblasts were investigated in vitro and in an ex vivo skin growth model. In addition, the effect of pH on keratinocyte differentiation as measured by the expression of cytokeratins 1 (K1) and K5 was studied. RESULTS: We demonstrated that the optimal pH for both keratinocyte and fibroblast proliferation is between pH 7.2 and 8.3. The optimal pH for growth from ex vivo skin explants was pH 8.43 which correlates with a previously reported improvement in skin graft take at higher pHs. Expression of K1 was found to be elevated in keratinocytes at a low pH. CONCLUSIONS: These results demonstrate that skin cells and explants proliferate and migrate at pHs higher than the physiological pH and that at lower pH keratinocytes express a differentiated keratinocyte phenotype. A better understanding of the responses of the cellular components of skin to fundamental physiological variables such as pH may help inform improved clinical wound care.
Assuntos
Fibroblastos/fisiologia , Concentração de Íons de Hidrogênio , Queratinócitos/fisiologia , Pele/lesões , Cicatrização/fisiologia , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Proliferação de Células , Células Cultivadas , Humanos , Queratina-1/metabolismo , Queratina-5/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/citologiaRESUMO
Clinical signs of a fatal disease resembling those of canine distemper were observed in two groups of captive wild dog (Lycaon pictus) pups 13 days after vaccination with a commercially available combination vaccine for dogs which contained a live attenuated strain of canine distemper virus. Histopathological examination of tissues revealed the presence of intranuclear inclusion bodies in neurons and lesions resembling canine distemper as well as colonies of an Encephalitozoon sp. in the central nervous system and kidneys. Lesions were observed in both organs which resembled those described in other species infected with Encephalitozoon cuniculi.