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 observe the expression and distribution of transforming growth factor-β1 (TGF-β1) in the healing process of bile duct and discuss its function and significance in the process of benign biliary stricture formation. Methods An injury to bile duct of dog was made and then repaired. The expression and distribution of TGF-β1 in the tissue at different time of the healing process were studied after operation with immunohistochemical SP staining. Results TGF-β1 staining was observed in the granulation tissue, fibroblasts and endothelial cells of blood vessels. High expression of TGF-β1 was observed in the healing process lasting for a long time. Conclusion The high expression of TGF-β1 is related closely with the fibroblast proliferating activity, extracellular matrix overdeposition and scar proliferation in the healing process of bile duct.
OBJECTIVE The biological effects of recombinant human epidermal growth factor (rhEGF) and recombinant human fibroblast growth factor (rhFGF) were evaluated on the model of incised wounds in mini pigs. METHODS Total of 160 incised wounds in 16 mini pigs were divided into two groups (rhEGF group and rhFGF group), each containing 80 wounds. In rhEGF group, 60 incised wounds were treated with different dosages of rhEGF (50, 10 and 0.5 micrograms/wound), and another 20 wounds were treated with solvent as control group. In rhFGF group, all wounds were treated in the same way as described in rhEGF group, the dosages of rhFGF were 150, 90 and 30 U/cm2 respectively. The measurements of cavity volume and area in wound, histological examination were used to evaluate the results of wound healing. RESULTS The results showed that wound healing was accelerated in all wounds treated with rhEGF and rhFGF. In rhEGF group, the velocity of re-epithelialization was faster than that of rhFGF group, however, new granulation tissue in rhFGF was more than that of rhEGF group. CONCLUSION The results indicate that rhEGF and rhFGF can stimulate wound healing, however, the mechanisms and the biological effects involved in these processes are quite different. It suggests that it is better to use rhFGF in those wounds which need more granulation tissue formation and use rhEGF in the wounds which mainly need re-epithelialization.
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 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 investigate the effect of heterogeneous (swine) acellular dermal matrix (s-ADM) and autologous overthin split-thickness skin (auto-OTS) composite grafting in repair of deep burns at articular sites. METHODS: From May 1999 to April 2000, 19 articular sites in 16 patients, including 14 males and 2 females, were treated. In all the 19 sites of deep burn, the total burn area varied from 2% to 48% and the full-thickness burn area varied from 1% to 35%. After the primary escharectomy (1 to 5 days later) and complete hemostasis, the s-ADM was utilized to cover the exposed articular sites and the auto-OTS was transferred on the surface of sutured s-ADM. The size of s-ADM applied to each patient varied from 25 cm2 to 150 cm2. Regular skin grafting was adopted elsewhere other than the articular site. The survival rate of all skin grafting was evaluated and pathological examination was performed. RESULTS: The survival rate of the composite skin was (90.80 +/- 18.34)%, which was obvious higher than the survival rate of contiguous granulosum skin grafting (P lt; 0.05) and almost the same with that of snip skin grafting(P gt; 0.05). The survived composite skin appeared as smooth and soft as normal skin, and the function of articular site almost recovered with neglectable hypertrophic scar. The pathological examination revealed that the normal cell grew into s-ADM with regularly arranged collagen fiber and neovascularization in the matrix. CONCLUSION: The combination of s-ADM and auto-OTS graft is cheap and effective method to cover wound and minimize hypertrophic scar.
Thirtysix patients with a total of 89 places of skin wounds which was involved with various depths of skin were treated by application of autogenous whole layer skin mash, in which the ratio betweenepidermis and dermis was 3∶1 and the ratio between the donor area and that of the recipient ranged from 1∶5 to 1∶20. The patients were followed from 6 months to 18 months. The results were excellent in 58, good in 15, fair in 11 and bad in 5. Different depths of the skin wounds such as superficial dermis, deep dermis, subcutis and deep fascia were responsible in seqence for the decreasing percentage of survival of the microcutaneous particle graft. It was shown that a considerably high survival might be obtained in both wounds down to fat or fascial layer.
Objective To investigate the feasibility of differentiation of the marrow mesenchymal stem cells (MSCs) into the cells of the skin appendages andthe mechanism of their involvement in the wound healing. Methods The bone marrow was collected from Wistar rats by the flushing of the femurs, MSCs were isolated and purified by the density gradient centrifugation. Then, the MSCs were amplified and labelled with 5-bromo-2′-deoxyuridine (BrdU). The full-thickness skin wounds with an area of 1 cm×1 cm were made on the midback of the homogeneous male Wistar rats. At the same time, 1×106/ml BrdU-labelled MSCs were infused from thepenile vein. The specimens were harvested from the wound tissues on the 3rd dayand the 7th day after operation and were immunohistochemically stained by either BrdU or BrdU and pan-keratin. Results The BrdU positive cells appeared in thehypodermia, the sebaceous glands, and the hair follicles of the wounds, as wellas the medullary canal of the femurs. The double-staining showed the BrdU positive cells in the sebaceous glands and the hair follicles of the wounds expressedpan-keratin simultaneously. Conclusion During the course of the wound healing, MSCs are involved in the wound repair and can differentiate into the cells ofthe skin appendages under the microenvironment of the wound.
OBJECTIVE: With the recognization of the mechanism of wound healing, some topical agents are created and applied in trauma to improve the healing rate of wounds. The main purpose of this study is to investigate the effect of some topical agents on the healing rate of deep second-degree burn wounds. METHODS: One thousand five hundred and sixty-three patients with deep second-degree burn wounds(total burn surface area lt; or = 10%) were involved in this study from January 1982 to December 1999. According to the application time of different treating measures including supplement of Zn, application of growth factors and collagenase, the patients were divided into 3 groups, wound healing rates were compared. RESULTS: Before 1991, none of special topical agents were used, and the healing time of deep second-degree burn wounds was(23.8 +/- 3.5) days. From 1991 to 1996, with the topical application of SD-Ag-Zn, which can provide Zn for cells taking part in wound healing, the healing time of deep second-degree burn wounds was (20.6 +/- 3.2) days, earlier than no special topical agents (P lt; 0.05). From 1997 to 1999, growth factors such as basic fibroblast growth factor(bFGF) and epithelial growth factor (EGF) and collagenases were applied in wound treatment combining with SD-Ag-Zn, wound healing time was (16.2 +/- 2.8) days, earlier than no special topical agents (P lt; 0.01) and simple SD-Ag-Zn application (P lt; 0.05). CONCLUSION: It indicates that the improvement of topical agents can accelerate wound healing speed.
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.