RESUMO
Objective@#To explore the clinical application of ultra-pulsed CO2 laser skin abrasion combined with micro-skin graft in the treatment of skin depigmentation.@*Methods@#From January 2010 to June 2014, depigmented skin specimens were used for ultra-pulsed CO2 laser skin abrasion treatment, at 0, 10, 20, 30, 40, 50, 60 mJ. HE stain was performed to observe the abrasion depth under the 100 times microscope view. The most appropriate parameter was set to completely remove the epidermis, and leave dermis undamaged. From January 2011 to December 2017, 16 patients with skin depigmentation, 12 males and 4 females, aged 12-47 years, were treated with super-pulsed carbon dioxide laser and autologous microdermis transplantation. At 1, 3, 6 and 12 months after the operation, patients′ photos were record. The color improvement was analyzed using Image-Pro Plus 6.0 software.@*Results@#The laser energy for complete epidermis removal is different at different sites. It is 50 mJ for back skin, 40 mJ for face and hand skin and 30 mJ for neck skin. After one year of follow-up, there was no hypertrophy scar caused by over-abrasion in all 16 patients. Combined with the micro-skingrafting, 15 patients with skin depigmentation were completely resolved, with more than 90%color improvement rate. The improvement rate was 75% in a patient with un-uniform appearance, due to part failure of micro-skin graft. The neck movement and uncertain fixation were the reasons.@*Conclusions@#The appropriate energy parameters can control the abrasion depth to avoid the hypertrophic scar. Combined with micro-skin graft, the depigmentation area can be improved with uniform color and reliable effect.
RESUMO
Endothelins (ETs) and sarafotoxins (SRTXs) belong to a family of vasoconstrictor peptides, which regulate pigment migration and/or production in vertebrate pigment cells. The teleost Carassius auratus erythrophoroma cell line, GEM-81, and Mus musculus B16 melanocytes express rhodopsin, as well as the ET receptors, ETB and ETA, respectively. Both cell lines are photoresponsive, and respond to light with a decreased proliferation rate. For B16, the doubling time of cells kept in 14-h light (14L):10-h darkness (10D) was higher compared to 10L:14D, or to DD. The doubling time of cells kept in 10L:14D was also higher compared to DD. Using real-time PCR, we demonstrated that SRTX S6c (12-h treatment, 100 pM and 1 nM; 24-h treatment, 1 nM) and ET-1 (12-h treatment, 10 and 100 pM; 24- and 48-h treatments, 100 pM) increased rhodopsin mRNA levels in GEM-81 and B16 cells, respectively. This modulation involves protein kinase C (PKC) and the mitogen-activated protein kinase cascade in GEM-81 cells, and phospholipase C, Ca2+, calmodulin, a Ca2+/calmodulin-dependent kinase, and PKC in B16 cells. Cells were kept under constant darkness throughout the gene expression experiments. These results show that rhodopsin mRNA levels can be modulated by SRTXs/ETs in vertebrate pigment cells. It is possible that SRTX S6c binding to the ETB receptors in GEM-81 cells, and ET-1 binding to ETA receptors in B16 melanocytes, although activating diverse intracellular signaling mechanisms, mobilize transcription factors such as c-Fos, c-Jun, c-Myc, and neural retina leucine zipper protein. These activated transcription factors may be involved in the positive regulation of rhodopsin mRNA levels in these cell lines.