Clinical application of infrared ray thermal imagine combined with the method of "two longitudinal and five transverse lines" in locating the perforator of the anterolateral thigh perforator flap in children / 中华显微外科杂志

Objective:To explore the value of clinical application of the infrared ray thermal imaging (IRTI) combined with the method of "two longitudinal and five transverse lines" in locating the perforators in the transfer of free anterolateral thigh perforator flap (ALTPF) in children.Methods:From November 2018 to November 2022, 13 children (8 boys and 5 girls) aged 2 to 12 years old (6.3 years old in average) who received free ALTPF transfers were included in this study. Causes of injury were 6 by car accidents, 2 by falls, 3 by crushing injuries and 2 by burning scars. Injury sites were 2 in head, 1 in trunk, 5 in hand and 5 in ankle. The size of soft tissue defect was 2.0 cm×4.2 cm-9.0 cm×16.0 cm, and the size of ALTPF was 2.3 cm×4.5 cm-6.0 cm×20.0 cm. The remaining wound was covered with medium thick skin grafts. IRTI combined with the method of "two longitudinal and five transverse lines" was applied to preoperatively locate the pedicle and design the ALTPF. Intraoperatively, the pedicles were explored within the region of anterolateral thigh. The rate of perforrator location and sensitivity of the infrared thermography were calculated. All donor sites were directly sutured. Standard postoperative management included anti-infection, anti-coagulation, anti-convulsion and blood volume expansion with adequate warming. Regular outpatient follow-ups were conducted through various means such as home visits, telephone calls, WeChat and text messages to observe flap survival and donor site healing.Results:All 13 patients completed the 3 to 35 (11.0±1.5) months of postoperative follow-up. All 13 flaps survived well, with good colour and texture, and without obvious bloating. Only one bloated flap had a local repair at the inner ankle with a flap thinning surgery in the stage Ⅱ surgery. Then all flaps achieved satisfaction appearance in all patients. All the donor sites healed at stage I. Two patients showed significant early scar hypertrophy in the donor site, which then gradually stabilised 12 months later. All patients had good functional recovery. Before surgery, a total of 38 perforators were discovered and 40 perforators were found intraoperatively. Of the 40 perforators, 3 were not explored before operation, which were located in the proximal part of Zone Ⅰ, Zone Ⅲ and Zone Ⅳ, respectively. The sensitivity of infrared thermography was found at 92.5% in preoperative detection and location of perforators, with a positive prediction at 97.3%.Conclusion:IRTI combined with the method of "two longitudinal and five transverse lines" in locating perforators is safe and reliable in the design of ALTPFs in children. It provides an additional and reliable option for location of perforator in the design and harvesting of ALTPFs in children.

Effect of PRP on the proliferation of dermal papilla cells and hair follicle regeneration in mice / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the effects of platelet-rich plasma (PRP) on the proliferation of dermal papilla cells (DPCs) and hair follicle regeneration.</p><p><b>METHODS</b>PRP was prepared using the double-spin method and applied to DPCs. The proliferative effect of activated PRP on DPCs was measured using MTT assay. To understand the influence of activated PRP on the hair-inductive capacity of DPCs, freshly isolated epidermal cells and DPCs of passage 4 were resuspended, mixed with various concentrations of a PRP (0%, 5% or 10%) and were then transferred to a grafting chamber, which was implanted onto the dorsal skin of nude mice. The chambers were removed 1 week after grafting and HF formation was monitored for 4 weeks; the graft site was harvested and processed for histological examination.</p><p><b>RESULTS</b>Activated PRP increased the proliferation benefited the aggregative growth of DPCs. There are significant difference in the yield of hair follicles compared with 10% PRP (344 +/- 27) with 0% PRP (288 +/- 35) in the area of reconstituted skin (P < 0.05). The areas treated with PRP demonstrated an increase in hair follicles density of 19.4%. Ten percent PRP (18 +/- 1) d also can significantly shorten the time of hair formation, compared with 0% PRP (20 +/- 1) d (P < 0.05).</p><p><b>CONCLUSIONS</b>There is a considerable effect of PRP on the time of hair formation and the yield of hair follicles reconstitution.</p>

Implantation of newborn mice skin cells with chamber method to construct a model of hair follicle development / 中华整形外科杂志

<p><b>OBJECTIVE</b>To construct a convenient, reliable and visual model of hair follicle development to test the hair-inductive potential of follicular cells and investigate the molecular mechanism regulating hair follicle morphogenesis and cycling.</p><p><b>METHODS</b>An open chamber was transplanted into the nude mice dorsal skin, dermal and epidermal cells isolated from newborn C57BL/6 mice skin were mixed at a specific ratio and then injected into the chamber together, 1 week after transplantation, the chamber was removed, and then, hair formation and regeneration after hair plucking was observed.</p><p><b>RESULTS</b>1 week after cells implantation, the wound was moist without apparent contraction and among that pink and translucent tissue was formed. 2 weeks after implantation, the wound healed completely. 3 weeks after implantation, black hair grew from the skin was observed. 4 weeks after implantation, thick and black hair grew from the skin vertically. Completely developed structure of hair follicle was observed with paraffin section and HE staining. 1 week after plucking, new hair had regrown. The ratio of cell component was varied, whereas the other component was fixed at 1 x 10(7) cells. When the number of epidermal cells was reduced to 1 x 10(6) cells, the efficiency of hair follicle reconstitution was mostly unchanged. On the other hand, the density of newly formed hair was diminished considerably by reducing the number of dermal cells to 5 x 10(6) cells or lower. Neither epidermal cells nor dermal cells transplanted alone formed hair follicle.</p><p><b>CONCLUSIONS</b>Newborn mice skin cells transplanted by chamber method can construct a complete model of hair follicle development, which can be used to test the hair-inductive potential of follicular cells and investigate the molecular mechanism regulating hair follicle morphogenesis and cycling.</p>