Background: Although it has been recognized that photoageing and chronological ageing differ in various morphological and biological aspects, the characteristic alterations of cutaneous neurogenic factors in photoaged...Background: Although it has been recognized that photoageing and chronological ageing differ in various morphological and biological aspects, the characteristic alterations of cutaneous neurogenic factors in photoaged skin are poorly characterized. Objectives: To characterize cutaneous neurogenic factors, including innervation, neuropeptides, nerve growth factor and interactions of mast cells, in photoaged skin. Subjects and methods: Paired biopsy specimens were obtained from sun-exposed volar forearm skin and from sun-protected dorsal upper arm skin of 20 elderly subjects. Various cutaneous neurogenic factors, including innervation, neuropeptides, neurokinin receptor, nerve growth factor, neurogenic inflammation and morphology of mast cells, were compared in sun-exposed vs. sun-protected skin quantitatively and qualitatively. Results: Cutaneous neurogenic factors associated with photoageing were characterized by a significant increase in the densities of dermal and intraepidermal nerve fibres, a correlation between epidermal innervation and the severity of photodamage, increases in the number of neuropeptidergic sensory nerve fibres in the dermis and in tissue levels of sensory neuropeptides, increases in the content of nerve growth factor, reduced expression of neurokinin receptor 1 by epidermal keratinocytes and by vascular endothelial cells and a tachykinin-specific reduction of cutaneous neurogenic inflammation. Mast cells in photodamaged skin showed several characteristic morphological features, including various degrees of activation and an intimate association with fibroblasts, which were distinct from those in sun-protected skin. Furthermore, mast cells in photodamaged skin possessed larger amounts of substance P within their granules than did those in sun-protected skin. Conclusions: These findings document for the first time characteristic alterations of cutaneous neurogenic factors in photodamaged skin and suggest that the cutaneous nervous system may be involved in photoageing processes.展开更多
Knowledge of the accurate margins of a lentigo maligna melanoma (LMM) is crucial in the presurgical evaluation of the patient. Towards this end clinicians have utilized the Wood’ s lamp and dermoscopy to help delinea...Knowledge of the accurate margins of a lentigo maligna melanoma (LMM) is crucial in the presurgical evaluation of the patient. Towards this end clinicians have utilized the Wood’ s lamp and dermoscopy to help delineate the borders of the LMM.However, many LMMs arise on photo damaged skin, making it difficult to determine the border of the LMM and separate it from the background lentiginous skin. We present a case of a patient with a recurrent LMM on the scalp that developed in a background of photodamage with diffuse melanocytic atypia and lentigines, making it virtually impossible to determine the precise margins of the LMM by clinical, Wood’ s lamp or dermoscopic examination. To avoid subjecting the patient to multiple staged excisions we attempted to determine the margins of the LMM by utilizing in vivo confocal laser scanning reflectance microscopy. Using this, it was apparent that there were increased numbers of atypical/dendritic intraepidermal melanocytes in all layers of the epidermis within the LMM. In contrast, skin not involved with the LMM, as viewed under confocal laser examination, had normal honeycomb architecture and no abnormal melanocytes. The confocally determined border was further confirmed by obtaining multiple punch biopsies that were evaluated by haematoxylin and eosin histology and immunohistochemistry. Based on this information, the presurgical margins were marked and the tumour excised accordingly. The excised tissue was examined with multiple- step sections and the margins were determined to be clear. There has been no evidence of tumour recurrence after 1 year. In conclusion, this case illustrates that confocal reflect ancemicroscopy, in conjunction with other in vivo optical instruments, can be utilized to enhance the accuracy for the presurgical margin mapping of LMM.展开更多
文摘Background: Although it has been recognized that photoageing and chronological ageing differ in various morphological and biological aspects, the characteristic alterations of cutaneous neurogenic factors in photoaged skin are poorly characterized. Objectives: To characterize cutaneous neurogenic factors, including innervation, neuropeptides, nerve growth factor and interactions of mast cells, in photoaged skin. Subjects and methods: Paired biopsy specimens were obtained from sun-exposed volar forearm skin and from sun-protected dorsal upper arm skin of 20 elderly subjects. Various cutaneous neurogenic factors, including innervation, neuropeptides, neurokinin receptor, nerve growth factor, neurogenic inflammation and morphology of mast cells, were compared in sun-exposed vs. sun-protected skin quantitatively and qualitatively. Results: Cutaneous neurogenic factors associated with photoageing were characterized by a significant increase in the densities of dermal and intraepidermal nerve fibres, a correlation between epidermal innervation and the severity of photodamage, increases in the number of neuropeptidergic sensory nerve fibres in the dermis and in tissue levels of sensory neuropeptides, increases in the content of nerve growth factor, reduced expression of neurokinin receptor 1 by epidermal keratinocytes and by vascular endothelial cells and a tachykinin-specific reduction of cutaneous neurogenic inflammation. Mast cells in photodamaged skin showed several characteristic morphological features, including various degrees of activation and an intimate association with fibroblasts, which were distinct from those in sun-protected skin. Furthermore, mast cells in photodamaged skin possessed larger amounts of substance P within their granules than did those in sun-protected skin. Conclusions: These findings document for the first time characteristic alterations of cutaneous neurogenic factors in photodamaged skin and suggest that the cutaneous nervous system may be involved in photoageing processes.
文摘Knowledge of the accurate margins of a lentigo maligna melanoma (LMM) is crucial in the presurgical evaluation of the patient. Towards this end clinicians have utilized the Wood’ s lamp and dermoscopy to help delineate the borders of the LMM.However, many LMMs arise on photo damaged skin, making it difficult to determine the border of the LMM and separate it from the background lentiginous skin. We present a case of a patient with a recurrent LMM on the scalp that developed in a background of photodamage with diffuse melanocytic atypia and lentigines, making it virtually impossible to determine the precise margins of the LMM by clinical, Wood’ s lamp or dermoscopic examination. To avoid subjecting the patient to multiple staged excisions we attempted to determine the margins of the LMM by utilizing in vivo confocal laser scanning reflectance microscopy. Using this, it was apparent that there were increased numbers of atypical/dendritic intraepidermal melanocytes in all layers of the epidermis within the LMM. In contrast, skin not involved with the LMM, as viewed under confocal laser examination, had normal honeycomb architecture and no abnormal melanocytes. The confocally determined border was further confirmed by obtaining multiple punch biopsies that were evaluated by haematoxylin and eosin histology and immunohistochemistry. Based on this information, the presurgical margins were marked and the tumour excised accordingly. The excised tissue was examined with multiple- step sections and the margins were determined to be clear. There has been no evidence of tumour recurrence after 1 year. In conclusion, this case illustrates that confocal reflect ancemicroscopy, in conjunction with other in vivo optical instruments, can be utilized to enhance the accuracy for the presurgical margin mapping of LMM.
