Objective To investigate the relationship between apoptosis in epidermal keratinocytes and efficacy of epidermal grafting. Methods Epidermal specimens were obtained from donor sites and depigmented area of 44 patients with vitiligo receiving epidermal grafting. The apoptosis in keratinocytes was determined by terminal deoxynucleotidyl transferase end-labeling (TUNEL) assay, and the expressions of caspase 3, 8, 9 as well as bcl-2 and P53 were evaluated by immunohistochemistry. Results As TUNEL assay showed, the number of apoptotic keratinocytes in epidermis from depigmented area differed significantly from that from donor sites.The expressions of caspase 3, 8 and 9 were mainly located in the membrane and cytoplasm of keratinocytes,and positive keratinocytes were predominately distributed in the middle and lower layer of the epidermis. Of the 44 patients, 19, 15 and 16 were positive for the expressions of caspase 3, 8 and 9 in the depigmented epidermis,respectively, and 9, 5 and 4 for those in the donor epidermis, respectively. P53 was expressed in neither donor epidermis nor depigmented epidermis, while Bcl-2 was weakly positive in donor epidermis and negative in depigmented epidermis. The number of apoptotic keratinocytes was higher in donor epidermis from patients failing to respond to the transplantation than in that from patients successfully treated by transplantation (15.83 ± 2.69 vs.9.24 ± 1.80, t = 10.96, P < 0.01 ). Conclusions There is an obvious apoptosis in keratinocytes from depigmented epidermis of patients with vitiligo, together with an increase in the expression of caspase 3, 8 and 9. The apoptosis in keratinocytes may be related to the efficacy of epidermal transplantation.

Objective:To evaluate performance of O-Z-O flaps in repair of adjacent facial skin defects.Methods:A retrospective analysis was conducted. A total of 60 patients with adjacent facial skin defects receiving O-Z-O flap repair were collected from the Third People′ s Hospital of Hangzhou from 2015 to 2018, including 50 with pigmented nevus, 4 with seborrheic keratosis, 3 with verruca vulgaris, 2 with basal cell carcinoma and 1 with squamous cell carcinoma. Among the 60 patients, 14 were males and 46 were females, with the age being 18 - 75 years. According to the condition of skin lesions, in situ resection was performed, and the optimal incision was designed; the "flap bridge", that is, the normal tissue between adjacent defects, was severed; according to the skin tension line and wrinkle line, residual ends of the two flap bridges were interlaced with each other, sutured and fixed interruptedly, and the wounds were repaired. Results:The skin defects could be completely covered by O-Z-O flaps in the 60 patients. All the patients received primary healing of incisions without scar hyperplasia after operation.Conclusions:The O-Z-O flap has advantages of flexible design and small incisions, and can be used for tension-reducing suture after excision of adjacent skin lesions. It is a good choice for repair of adjacent facial skin defects with satisfactory clinical effect.

Objective:To evaluate clinical efficacy of pedicled fat flaps in the repair of facial defects after skin tumor resection.Methods:Clinical data were collected from 39 patients with facial tumors in Department of Dermatology, The Third People′s Hospital of Hangzhou, and analyzed retrospectively. There were 20 males and 19 females, aged 55 ± 7.3 years (range, 42 - 80 years) , including 15 with basal cell carcinoma, 10 with squamous cell carcinoma, 5 with keratoacanthoma and 9 with solar keratosis. Postoperative skin defects varied from 1.5 cm × 3.0 cm to 8.0 cm × 4.5 cm in size. All patients received skin defect repair with pedicled fat flaps after tumor resection. Twenty-four hours after the surgery, survival condition of the flaps was observed. These patients were followed up at 1, 3 months after the surgery and every 3 months thereafter, and the shape and texture of the flaps and their matching degree with surrounding tissues were evaluated.Results:Twenty-four hours after surgery, the flaps survived well without infection in the 39 patients. Partial necrosis was observed at the distal end of the flaps in 2 cases, whose skin defects were on the lower eyelid, with the ratio of the flap length to pedicle width being greater than 3∶1, and wounds were healed after treatment in both of the 2 cases. One month after surgery, bloated appearance was observed in 3 cases, of which 2 had defects of the upper lip and 1 had defects of the cheek, and the ratios of flap length to pedicle width were less than 2∶1, 2∶1 - 3∶1, and greater than 3∶1 respectively. All patients were followed up for 1 - 12 months, with an average of 7 months. The color and texture of the flaps were good, and favorable function and shape were achieved in both the donor and recipient sites.Conclusion:The pedicled fat flap is markedly effective for the repair of facial skin defects, with high survival rate of flaps, high safety and reliability, and less damage to the donor site.

Objective:To investigate clinical efficacy of composite subcutaneous pedicled flaps in repairing full-thickness nasal alar defects.Methods:Clinical data were collected from 11 patients with basal cell carcinoma of nasal ala in Department of Dermatologic Surgery, the Third People′s Hospital of Hangzhou from August 2019 to September 2020, and analyzed retrospectively. There were 6 females and 5 males, aged 70 years in average (range, 56-87 years) . After tumor resection, full-thickness nasal alar defects were formed, a flap was designed along the inner side of the cheek and turned by 180 degrees to repair the nasal mucosal lining; then, a subcutaneous pedicled flap was designed along the ipsilateral nasolabial fold to repair the outer secondary defects and postoperative defects.Results:The mean diameter of postoperative defects was 1.8 cm (range, 1.5-2.5 cm) , and the mean diameter of the nasal lining was 0.9 cm (range, 0.6-1.5 cm) . Seven days after the operation, stitches were removed, wounds healed without complications, and all flaps survived with a satisfactory appearance. The follow-up period ranged from 1 to 13 months (average, 6 months). After scar maturation, all patients were satisfied with the aesthetic outcome. No tumor recurrence was observed during the follow-up period.Conclusion:The composite subcutaneous pedicled flap is safe and effective for the repair of full-thickness nasal alar defects, and has advantages of a well-hidden donor site, good color match, and stage-I operation for reconstruction.

Objective:To investigate the application of transverse closure of longitudinal incisions in repairing pentagonal full-thickness defects of the lower eyelid margin.Methods:A retrospective analysis was performed on clinical data collected from 26 patients with melanocytic nevi at the lower eyelid margin in Department of Dermatology, The Third People′s Hospital of Hangzhou from July 2016 to June 2019. Among the 26 patients, 10 were males, and 16 were females. After lesion resection, all the pentagonal full-thickness defects of the lower eyelid margin were repaired via transverse closure of longitudinal incisions.Results:All the pentagonal defects of the 26 cases were successfully repaired. The longitudinal incisions perpendicular to the eyelid were successfully converted into transverse incisions parallel to the eyelid margin and near the eyelash, and all incisions healed primarily. After surgery, mild congestion of the lower eyelid occurred in 3 patients, and temporary blurred vision in 1. During 1 - 2 years of postoperative follow-up, 26 patients all achieved symmetrical appearance of the skin and soft tissues around the eyes, without obvious postoperative scars or lower eyelid ectropion.Conclusions:Horizontal closure of longitudinal incisions can be used to repair the pentagonal full-thickness defects of the lower eyelid margin, because it can convert the incision closure line perpendicular to the lower eyelid margin into a horizontal transverse incision closure line parallel to the lower eyelid margin, so that the incisions and scars of the lower eyelid can be hided with a satisfactory cosmetic effect.

OBJECTIVETo fabricate organic-inorganic composite tissue engineering scaffolds for reconstructing calcified cartilage layer based on three-dimensional (3D) printing technique.

METHODSThe scaffolds were developed by 3D-printing technique with highly bioactive calcium-magnesium silicate ultrafine particles of 1%, 3% and 5% of mass fraction, in which the organic phases were composed of type I collagen and sodium hyaluronate. The 3D-printed scaffolds were then crosslinked and solidified by alginate and CaCl₂ aerosol. The pore size and distribution of inorganic phase were observed with scanning electron microscope (SEM); the mechanical properties were tested with universal material testing machine, and the porosity of scaffolds was also measured.

RESULTSPore size was approximately (212.3 ± 34.2) μm with a porosity of (48.3 ± 5.9)%, the compressive modulus of the scaffolds was (7.2 ± 1.2) MPa, which was irrelevant to the percentage changes of calcium-magnesium silicate, the compressive modulus was between that of cartilage and subchondral bone.

CONCLUSIONThe porous scaffolds for calcified cartilage layer have been successfully fabricated, which would be used for multi-layered composite scaffolds in osteochondral injury.

Bioprinting ; Cartilage ; growth & development ; Materials Testing ; Porosity ; Printing, Three-Dimensional ; Tissue Engineering ; methods ; Tissue Scaffolds ; chemistry