Clinicopathological Analysis of Acquired Melanocytic Nevi and a Preliminary Study on the Possible Origin of Nevus Cells.

BACKGROUND: The pathogenesis of acquired melanocytic nevi (AMN) is still unclear, and the origin of nevus cells has not been clarified. OBJECTIVE: To analyze the clinical features and pathological types of AMN and identify the possible origin of nevus cells. METHODS: A retrospective study of 2929 cases of AMN was conducted, and 96 specimens of intradermal and junctional nevi were selected. Immunohistochemical assays were performed to detect the expression of basement membrane component receptor DDR-1 and the molecular markers on epidermal melanocytes, dermal stem cells (DSCs), and hair follicle stem cells. RESULTS: Junctional nevi and compound nevi were prone to occur on glabrous skin, such as the palms, soles, and vulva, and on the extremities in children, whereas intradermal nevi tended to develop on the trunk, head, and face of adults. The immunohistochemical data revealed that both junctional nevi and intradermal nevi expressed the epidermal melanocyte surface markers E-cadherin, DDR-1, and integrin α6 and the DSC molecular markers NGFRp-75 and nestin. CD34 was expressed only in junctional nevi, whereas K19 was not expressed in any type of melanocytic nevi. There was no significant difference in molecular expression at different sites or in different ages of onset. Nestin expression was markedly stronger in the intradermal nevi than in the junctional nevi, but there was no difference between the superficial and deep nevus cell nests of intradermal nevi. CONCLUSION: AMN may have a multicellular origin that commonly follows the mode of Abtropfung. Furthermore, DSCs may partly or independently participate in the formation of nevus cells.

Systemic and flap inflammatory response associates with thrombosis in flap venous crisis.

Venous crisis represents the most common complication in flap surgery and often results in flap failure. The gold standard for free flap monitoring is frequent clinical examination. The current study examined the systemic inflammatory response during the immediate post-operative period following flap venous crisis. Superficial epigastric artery perforator flap transplantation was performed in a total of 30 rabbits. Fifteen animals received venous obstruction by vein ligation (venous crisis group, n = 15) and others were sham treated (control group, n = 15). Venous thrombosis was examined by immunohistochemistry staining. Plasma levels of inflammatory response markers (IL-6, IL-8, TNF-α, and C-reactive protein) and thrombosis biomarkers (von Willebrand factor and tissue factor) were measured at 0, 2, and 4 h post-operation by enzyme-linked immunosorbent assay. The mRNA levels of relevant biomarkers in the flap were analyzed with quantitative real-time PCR. Flap histopathological examination showed erythrocyte and neutrophil aggregations in venous lumen and erythrocyte diapedesis. At 8 h post-operation, serious edema and fibrinoid necrosis were observed and the venous lumen was almost blocked by thrombus. The venous crisis group had higher plasma levels of IL-8, TNF-α, and thrombosis biomarkers. Vein ligation also increased the mRNA levels of IL-8, TNF-α, C-reactive protein, von Willebrand factor, and tissue factor in the flap. No significant change in IL-6 levels was observed between the control group and the venous crisis group. Flap venous crisis was accompanied by the increase in a number of inflammatory and thrombosis markers, both in the peripheral blood and the flaps.

[The clinic application of thoracodorsal artery perforator flap: a report of 16 cases].

OBJECTIVE: To investigate the effects of free and pedicled thoracodorsal artery perforator (TDAP) flaps for repairing skin and soft tissue defects in limbs, neck, axillary and shoulder. METHODS: From October 2009 to Auguest 2011, 16 TDAP flaps were used to repair skin and tissue defects. Among them, five ipsilateral pedicled flaps were used to repair wounds in neck, axillary and shoulder. 11 free TDAP flaps were used to repair the wounds with bone or tendon exposure. In 12 cases, the flaps were pedicled with thoracodorsal artery and vein-lateral branches-perforators, in 4 cases, pedicled with thoracodorsal artery and vein-serratus anterior muscular branches-perforators. The deep fascia, the latissimus dorsi and thoracodorsal nerve were not included in all flaps. The flaps size ranged from 10 cm x 5 cm to 26 cm x 10 cm. RESULTS: All 16 flaps survived completely with primary healing both at donor site and recipent area. After a follow-up of 3 to 24 months, all flaps gained good texture and appearance. Only linear scar was left at donor area. The shoulder could move freely. CONCLUSIONS: TDAP flap has good texture, long vascular pedicle,and reliable blood supply, leaving less morbidity at donor site. The latissimus dorsi and thoracodorsal nerve are also preserved. The pedicled TDAP flap is an ideal flap for repairing the ipsilateral skin and soft tissue defects of the neck, shoulder, axillary. The free TDAP flap is suited for repairing skin and soft tissue defects of the extremities.