Tissue-engineered skin plays an important role in clinical applications,and even the rapid development of science and technology promotes the research about it.Choosing an appropriate animal model for wound repair is the prerequisite for the objective evaluation of the object of study.In this paper,the research progress of animal models of wound repair was introduced from several aspects,such as selection of experimental animals,making of wound models,skin-related cells and materials,wound healing evaluation indexes,etc.,hoping to provide reference for later research work.

Objective To explore a method for repairing the appearance and function of the cheek aesthetic unit.Methods A single volume of 100 ml to 150 ml of tissue expander was implanted at the lower edge of the injury area on the cheek.The first injection was performed 5 days after the operation and twice a week after the injection.It took an average of about 4 months to complete the expansion,with 3-5 times over expanded.The lesions were resurfaced with the expanded flaps,and long term follow-up was observed for flap survival.Results 17 cases of cheek lesions had been successfully reconstructed,with the color,texture of the expanded flaps well matched to the surrounding skin after 3-12 months follow-up.The facial expression functions and configurations were satisfied.Conclusions Excessive expansion of the prefabricated skin flap of the jaw and neck can repair the cheek aesthetic unit successfully,which is a practical method and meets the needs of aesthetic unit repair.

Objective:To investigate the effects of dexmedetomidine on monocyte pyroptosis in peripheral blood of patients with cardiac valve replacement.Methods:Forty-four American Society of Anesthesiologists physical status Ⅱ or Ⅲ patients of both sexes, aged 45-64 yr, with body mass index of 18-25 kg/m 2, of New York Heart Association Ⅱ or Ⅲ, scheduled for elective cardiac valve replacement, were divided into 2 groups ( n=22 each) using a random number table method: dexmedetomidine group (group Dex) and normal saline group (group NS). In group Dex, dexmedetomidine was intravenously infused in a dose of 0.5 μg/kg over 10 min starting from the end of anesthesia induction, followed by a continuous infusion at 0.5 μg·kg -1·h -1 until the end of operation, while the equal volume of normal saline was given instead of dexmedetomidine in group NS.Before skin incision (T 1), at 30 min after the beginning of cardiopulmonary bypass (CPB) (T 2), immediately after the end of CPB (T 3) and at 24 h after CPB (T 4), the blood samples of internal jugular vein were collected for determination of the concentrations of plasma interleukin-18 (IL-18) and IL-1β (by enzyme-linked immunosorbent assay), and the expression of NOD-like receptor family, pyrin domain containing 3 (NLRP3), caspase-1 and gasdermin-D (GSDMD) in monocytes (by Western blot). The intraoperative consumption of propofol, sufentanil and norepinephrine, time of postoperative mechanical ventilation and time of intensive care unit stay were recorded. Results:The levels of plasma IL-18 and IL-1β and expression of NLRP3, caspase-1 and GSDMD in monocytes were significantly higher at T 2-4 than at T 1 in two groups ( P<0.05). Compared with group NS, the levels of plasma IL-18 and IL-1β were significantly decreased and the expression of NLRP3, caspase-1 and GSDMD was down-regulated at T 2-4, postoperative mechanical ventilation time was shortened ( P<0.05), and no significant change was found in the consumption of propofol, sufentanil and norepinephrine and time of intensive care unit stay in group Dex ( P>0.05). Conclusion:The mechanism by which dexmedetomidine reduces inflammatory responses may be related to inhibiting the NLRP3/caspase-1 pathway and reducing monocyte pyroptosis in the patients undergoing cardiac valve replacement.

Objective: To investigate the effects of PRX-2 gene on phenotype changes in epidermal stem cells differentiating into sweat gland cells. Methods: Epidermal stem cells and sweat gland cells separated and cultured from healthy foreskin and adult full-thick skin respectively, were identified by immunofluorescence staining. Lentiviral vector-mediated overexpression and knockdown of PRX-2 gene in epidermal stem cells were performed respectively, with empty vector-mediated epidermal stem cells as a control group. Overexpression、blank control and knowdown group′s PRX-2 expressions in gene and protein levels were detected using RT-PCR and Western blot technology. The ESCs of each group were co-cultured with sweat gland cells through transwell plate, and the expressions of CEA and β1 integrin in epidermal stem cells were determined by flow cytometry before and after co-culturing. Results: Epidermal stem cells and sweat gland cells were in line with their respective specific antigens. Before co-cultured, epidermal stem cells highly expressed β1 integrin (98.69±0.67)%, hardly expressed CEA (6.20±3.15)%. After co-cultured, β1 integrin expression levels were showed as knockdown group (19.30±0.53)% blank control group (51.20±0.79)%> overexpress group (45.91±0.93)%. There had significant differences between those of each two groups. Conclusions PRX-2 gene can inhibit the phenotypic change of Epidermal Stem Cells differentiating into Sweat Gland Cells and improve the ability to maintain their own specific antigens.