title: [Biological dressing with human hair keratin-collagen sponge-poly 2-hydroxyethyl methacrylate composite promotes burn wound healing in SD rats].
abstract: OBJECTIVE
  To develop a composite material containing human hair keratin (HHK), collagen sponge (inner layer) and poly 2-hydroxyethyl methacrylate (PHEMA) film that allows sustained release of polydatin and test its effect as a biological dressing in promoting burn wound healing in SD rats.
  
  
  METHODS
  Three HHK materials with fast, moderate, and low degradation rates were mixed at the ratio of 4:3:3 to prepare a reticular structure, which was processed into a composite material with bovine tendon-derived collagen sponge, and further complexed with HEMA film containing PD prepared by polymerization. Degree II burn wound was induced in SD rats by scalding and within postburn day 2-5, the wounds were cleansed and covered with the composite material or with glutaraldehyde-treated porcine skin (positive control). At week 1, 2, 4, 6 and 8 following wound dressing, 6 full-thickness skin samples were harvested from the wounds for histological observation and immunohistochemical detection of collagen and elastic fibers, and the wound healing time and healing rate were recorded.
  
  
  RESULTS
  The prepared collagen sponge film was transparent and porous (50-300 microm in diameter) and allowed sustained PD release into normal saline within 48 h. Compared with the porcine skin, the composite material reduced exudation and maintained ideal moisture of the wound, and significantly shortened the wound healing time (P=0.000). On day 7, 14, and 21 following dressing, the composite material and porcine skin significantly increased the wound healing rate as compared with the negative control group (P=0.000), and on day 14, the composite achieved significantly greater healing rate than the porcine skin (P<0.05).
  
  
  CONCLUSIONS
  HHK-collagen sponge-PHEMA/PD composite as a dressing material promotes burn wound healing in rats by allowing in vivo construction of tissue engineered epidermis. PHEMA is feasible for sustained drug delivery in this composite.
authors.affiliation: Department of Histology and Embryology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors.forename: Ying-hua
authors.initials: YH
authors.lastname: Chen
authors.forename: Wei-ren
authors.initials: WR
authors.lastname: Dong
authors.forename: Qing-yuan
authors.initials: QY
authors.lastname: Chen
authors.forename: Bing-lei
authors.initials: BL
authors.lastname: Zhao
authors.forename: Zhong-zhi
authors.initials: ZZ
authors.lastname: Zou
authors.forename: Ying-qing
authors.initials: YQ
authors.lastname: Xiao
authors.forename: Guo-dong
authors.initials: GD
authors.lastname: Hu
authors.forename: Xin-xia
authors.initials: XX
authors.lastname: Qiu
mesh_terms: D000818:Animals; D001684:Biological Dressings; D002056:Burns / Q000188:drug therapy*; D002417:Cattle; D003094:Collagen / Q000627:therapeutic use*; D016503:Drug Delivery Systems; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D005960:Glucosides / Q000494:pharmacology; D006801:Humans; D007633:Keratins / Q000627:therapeutic use*; D011102:Polyhydroxyethyl Methacrylate / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013267:Stilbenes / Q000494:pharmacology; D013552:Swine; D023822:Tissue Engineering; D014945:Wound Healing
chemical_list: D004365:Drugs, Chinese Herbal; D005960:Glucosides; D013267:Stilbenes; D011102:Polyhydroxyethyl Methacrylate; D007633:Keratins; D003094:Collagen; C058229:polydatin