Objective To explore the mechanism of full-thickness burn wound healing with autoskin grafting in fault hypodermis wound of granulation excision and to evaluate its effect.Methods By the techniques of clinical observation, histopathology, immunohistochemistry,TEM and FCM,we observed changes of the activity andstructure of grafted skin and the granulation tissue,collagnous fiber,microvessels,the ultramicrostructure of fibroblasts and the expression of basic fibroblast growth factor(bFGF) in the base of autoskin grafting in fault hypodermis wound in burned adult minipigs(Group A), and compared with traditional method of autoskingrafting on the basilar fibrous tissue wound of scraped partly granulation being(Group B) and control group (Group C, without treatment except de-fur).Results The grafted skin survived after 3 days of operation, and it had less injury and higher proliferative index(PI) in group A than in group B. The hyperplasiaof granulation tissue and vascular endothelial and the expression of bFGF were more evident in group A. After 5 days, the proliferation of endothelial cells and granulation and the protein synthesis of fibroblasts were more active in groupA, and at this moment, fresh collagen appeared and proliferated more actively in group B. After 7-14 days, epidermic structure and dermic microvascular density became normal gradually, the granulation on grafting base matured and transformed into fibrous connective tissue in group A. The same change deferred about 2 days in group B. After 21 days, the above pathologic change in group A was less than that in group B. After 3060 days of operation, Group A achieved much less contraction and transfiguration than Group B, and the grafted skin was tender and movable. Conclusion Autoskin grafting in fault hypodermis wound of granulation excision has a better effect than traditional operation.
OBJECTIVE: To investigate the effect of nerve growth factor(NGF) on the burn wound healing and to study the mechanism of burn wound healing. METHODS: Six domestic pigs weighting around 20 kg were used as experimental animals. Twenty-four burn wound, each 2.5 cm in diameter, were induced on every pigs by scalding. Three different concentrations of NGF, 1 microgram/ml, 2.5 micrograms/ml, 5 micrograms/ml were topically applied after thermal injury, and saline solution used as control group. Biopsy specimens were taken at 3, 5 and 9 days following treatment and immunohistochemistry method was used to detect the epidermal growth factor(EGF), EGF receptor (EGF-R), NGF, NGF receptor (NGF-R), NGF, NGF-R, CD68 and CD3. RESULTS: The expression of EGF, EGF-R, NGF, NGF-R CD68 and CD3 were observed in the experimental group, especially at 5 and 9 days, no expression of those six items in the control group. CONCLUSION: NGF can not only act directly on burn wound, but also modulate other growth factors on the burn wound to accelerate the healing of burn wound.
OBJECTIVE: To summarize the application of simple skin traction technique in repair of soft tissue defect of limb. METHODS: From 1999, 42 cases of soft tissue defect of limbs were repaired by simple skin traction technique instantly; the defect area ranged from 2.5 cm x 2.0 cm to 8.0 cm x 6.5 cm. RESULTS: The soft tissue defect less than 8.0 cm can be sutured instantly. All of the wound achieved primary healing without infection and necrosis of skin edge, the circulation and sensation of limbs were normal; healing time was 10 days to 16 days, 12.8 days on average. Thirty-two cases were followed up for 6 months; the shape and function recovered well. CONCLUSION: Simple skin traction technique is a good option to repair the soft tissue defect of limbs.
To investigate the best way of using fibroblast growth factor (FGF) in wound healing, the following experiments were performed. Twelve Wistar rats were chosen. Four 1.5 cm x 1.5 cm middle-thick skin wounds were made in the back of each rat, 2 in each side, and labelled as number 1 to 4. Number 1 wound of each rat was used as control, only PBS was applied to the wound, 50 microliters per time, twice a day from the first day to 11th day. Number 2 wound was sustained medication group, 50 microliters 4 micrograms/ml FGF was applied twice a day from the first day to 11th day; Number 3 wound was early medication group, 50 microliters 8 micrograms/ml FGF was applied twice a day from the first day to 5th day; Number 4 wound was late medication group, 50 microliters 8 micrograms/ml FGF was added twice a day from the 5th day to 11th day. By day 4, 8, 12 and 16, the area of wounds were measured, and the healing time of each wound was recorded. The elastic fiber, collagen fiber and DNA content were measured by immunohistological method. The result showed that the elastic fiber, collagen fiber and DNA content in the groups of FGF used were more than those in the control group. The healing time of the control group was 14.4 days while that of the early meduation group was 13.4 days, late medation group was 13.5 days and sustained medication group was 12.2 days. It was suggested that FGF could accelerate the wound healing, and sustained use of FGF was the best way of giving the drug.
OBJECTIVE To explore the healing mechanism of full-thickness wound treating by the intermingled skin transplantation of large sheet allograft with autograft through studying the expression of laminin (LN). METHODS Thirty-six SD rats with 10% to 15% of total body surface area (TBSA) full-thickness were made. After 3 days, the devitalized tissue were excised and transplanted a large sheet of allograft from Wistar rats and islets of autografts were implanted 3 days later. On day 3, 5, 7, 14, 21 after allografting, the expression of LN in the grafts were detected by immunohistochemistry. RESULTS On the 7th day postallografting, LN, which played positive action of epidermal cell adhesion, still retained in the allodermis after the rejection of alloepidermis occurred. On the 14th day postallografting, there appeared scattered LN underneath the epidermal cells migrating from islets of autografts. On the 21st day postallografting, LN in the basement membrane of skin grafts had completely formed. CONCLUSION The intermingled transplantation of large sheet allograft with autograft may provide components of basement membrane for wound healing, which may help to improve the appearance and function of skin.
For observation of the change of transforming growth factor-beta 1 (TGF-beta 1) gene expression in the process of skin wound healing, the following experiments were performed. Sixteen Wistar rats were chosen. At each side of the rat’s back, a 1 cm x 1.5 cm middle-thick skin wound was made. After 3, 6, 9 and 12 days, the specimens were taken from the wounds. For each specimen, half of it was used for RNA extraction, and underwent dot blotting; and the other half was frozen immediately and underwent in situ hybridization. The probes were dig-labeled PDGF-BB cDNA probe and TGF-beta 1 probe. The results showed that TGF-beta 1 gene was expressed mainly in fibroblast, epithelial cell and capillary endothelial cell. The peak of TGF-beta 1 mRNA content was in the 6th day postoperatively. After that, the content of TGF-beta 1 decreased to normal. It was suggested that TGF-beta 1 gene expression was in close relation with healing process. TGF-beta 1 may play an important regulatory role in the skin wound healing.
OBJECTIVE: To investigate the method of improving the vitality of skin graft on donor site of the great toe-nail skin flap. METHODS: From June 1982 to April 1998, 252 cases of the great toe-nail flaps with piece of phalangeal bone and 18 cases of the simple great toe-nail flap were repaired with thin skin graft and packed under proper pressure. The stitches were removed two weeks later in common situation. It should be postponed on split thickness or partial survival skin flap avoiding early mobilization. RESULTS: Sixty-six cases of skin graft were necrotic after operation. Among them, 38 cases needed second skin grafting and 28 cases were healed after changing dressing. The survival rate of skin grafting was obviously higher on phalangeal marrow surface than on periosteum of the naked phalange. Contracture of the skin graft after operation made the retained skin flap expanding from medial side to lateral side and covered the whole plantar surface of the great toe. CONCLUSION: The survival rate of the skin graft on donor foot is improved after adopting the improved measures on taking the flap from great toe and paying attention to skin graft planting and packing. Free flap grafting is advocated for repairing of the wound on donor area of the great toe nail flap.
Objective To explore the expression characteristics of chaperone interacting protein (CHIP) in normal, scar and chronic ulcer tissues and its relationship with wound healing. Methods Twenty biopsies including scar tissues(n=8), chronic ulcer tissues(n=4) and normal tissues(n=8)were used in this study. The immunohistochemical staining (power visionTMtwo-step histostaining reagent) was used to explore the amount and expression characteristics of such protein.Results The positive expression of CHIP was observed in fibroblasts, endothelial cells and epidermal cells in dermis and epidermis. It was not seen ininflammatory cells. The expression amount of CHIP in scar tissues, chronic ulcer tissues and normal tissues was 89%, 83% and 17% respectively. Conclusion Although the function of CHIP is not fully understood at present, the fact that this protein is expressed only at the mitogenic cells indicates that it may be involved in mitogenic regulation during wound healing.
OBJECTIVE: To investigate the mechanism of overhealing alleviation by salvia miltiorrhiza (SM) in wound healing. METHODS: Fibroblasts were cultured in vitro, and SM was applied with different concentrations (40, 80, 160 and 320 micrograms/ml) and time(the 1st, 2nd, 3rd, 4th and 5th days) to influence their autocrine. The levels of transforming growth factor-β1 (TGF-β1) and epidermal growth factor (EGF) were determined by ELIAS and radioimmunoassay respectively. RESULTS: The SM could inhibit autocrine of TGF-β1 by fibroblasts (P lt; 0.05). However, it did not affect autocrine of EGF (P gt; 0.05). CONCLUSION: The above results indicate that SM reduces overhealing by inhibiting the autocrine of TGF-β1 selectively.
Abstract In order to understand the expression change of epidermal growth factor (EGF) gene and its distribution in tissue duringwound healing, 12 Winstar rats were divided into 4 groups. In each side of the back of every rat, 4 wounds of 1.5cm×1.5cm in size were made. After 4,8,12,16 days, one group of rats was sacrificed and tissues from wound were collected. By DIG-labelled probe hybridization in situ technique, EGF gene mRNA was detected. It was shown that EGF gene expression was evident during the whole stage of woundhealing, and the peak was in 8th day. It suggested that the promotion of EGF gene expression may lead to wound healing earlier.