Objective To investigated the distribution of epidermal stem cells in rat fullthickness wound tissues during the wound healing process and toelucidate the roles of epidermal stem cells in wound repair in vivo.Methods Eighty circular fullthickness wounds were produced on both sides of the back in 20 male Wistar rats labeled with BrdU 60 days previously (4 wounds in each rat). BrdU, β1 integrin and keratin 19 (K19) were employed to determine the epidermal stem cells with SP immunohistochemical methods, and the epithelialization wasdetermined with routine histological methods of HE staining on the 3rd, 7th, 14th, and 21st days after operation.Results No cells with positive immunostaining for β1 integrin, K19 and BrdU were found in granulation tissue of woundin both groups during the healing process. However, a few scattered β1 integrin and K19 positive cells were found within the stratum spinosum and stratum granulosum of the epidermis on the wound edges on the 3rd day post-injury. And these positive cells gradually became more and more in number, and mostly concentrated on the border of wound edges till the wounds healed. In addition, the number of positive cells for β1 integrin and K19 in the infected wounds was less than that in non-infected wounds. These positive cells for β1 integrin and K19 staining on the wound edge were also positively stained with BrdU in the cellular nuclei. Conclusion The above results indicate that ectopia of epidermal stem cells present a major function during wound epithelialization.
Objective To study the relationship between the adipose tissues and cutaneous morphogenesis on wound healing. Methods Adipose tissues’ participation in regulation of food intake, energy expenditure, fuel metabolism, and a variety of other physiological processes was reviewed in the latest literature. The wound healing was regulated by endocrine, paracrine, and adipocytederived molecules. Results Several factors secreted by adipose tissues (leptin, cytokines, growth factors, lipids, metallothioneins, ect) regulated wound healing. Conclusion Adipose tissues may play a vital role in the process of wound healing. Further understanding of the complex interaction between adipose cells and cutaneous morphogenesis is essential to explore the mechanism of wound healing.
Objective To review the current condition of growth factors and their application to clinical treatment of acute and chronic wounds. Methods Data from the literature and Medline were analyzed according to their different uses in acute and chronic wounds. Their potential side-effects were studied. Results All data showed that wound healing time in acute and chronic wounds was accelerated and wound healing quality was improved after treatment with growth factors. No sideeffect was observed. Conclusion The efficacy and safety of growth factors in improving wound healing were confirmed. However, some reconsideration aboutpotential problems of growth factors must be made to apply them clinically in the future.
Objective To develop a new kind of skin substitute, selective acellular porcine skin, to cover excised wounds in treatment of extensivedeep burns on the basis of controlled de-cell technique. Methods Partial thickness porcine skin was treated with 0.25% trypsin for 2 hours at 37℃ after crosslinked with glutaraldehyde, and then it was glued to a container with the edge embedded with glue. The skin was shaken in 0.5% SDS for 24 hours, and then washed before use. The selective acellular skin was used with micro-autografts on the dermal side to cover 2 surgically excised burn wounds in a patient. The recoveries of function and appearance were observed. Results Morphological observation showed that the treated porcine skin had an intact epithelial layer and an acellular dermis. After being used to cover burn wounds, its acellular dermis could serve as host dermal matrix, and its devitalized epithelial layer could prevent the dermis from drying. The devitalized epithelium wasfinally replaced by host epithelial cells, and the healed wounds could achieve good cosmetic and functional results. Conclusion Selective acellular porcine skin can be used as promising skin substitute to cover excised wounds.
OBJECTIVE: To describe the concept of "un-controlled wound repair" and review its current progress in basic research and clinical treatment. METHODS: The literature review and comprehensive analysis methods were used in this study. RESULTS: The results showed that the normal wound repair and "un-controlled" wound repair had made big progress in cellular, molecular and genetic levels in recent years and these progresses had enhanced the treatment progress in clinic. CONCLUSION: All data indicate that the wound repair is made a big progress both in basic and clinic fields. New high techniques, such as clone, biochip and stem cell and their use will promote the deep study of "un-controlled" wound repair.
OBJECTIVE To observe the effects of basic fibroblast growth factor(bFGF) on the healing of cutaneous chronic wounds. METHODS Twenty-eight cases with thirty-three wounds from trauma, diabetes, pressure and radiation injuries were locally treated with bFGF in a dosage of 150 U/cm2 wounds. The healing time of wounds was used to evaluate the treatment results. RESULTS The healing time in all of chronic wounds were accelerated. All wounds from trauma, diabetes and pressure were healed within 4 weeks and another 2 wounds from radiation injuries were healed over 4 weeks. The healing rate within 4 weeks was 93.9%. CONCLUSION The results indicate that bFGF can be used as a promoter to accelerate the healing of chronic wounds in clinic.
Objective To investigate the possible signaling mechanisms by which recombinant human plateletderived growth factor (rhPDGF) accelerated healingof cutaneous wound in diabetic rats. Methods Four full-thickness skin woundswere incised in the back of 26 male Wistar diabetic rats. The wounded rats were divided into 3 groups (7 or 8 rats each group). One group without treatmentwas used as a control, and the other 2 groups were treated with rhPDGF at a dose of 7.0 μg/cm2 wound or vehicle (DMSO/09% NaCl, vol/vol 1∶1) from 1 to14 days. The wound healing was evaluated by the measurements of the wound volume and area. Immunofluorescent and immunohistochemical staining were used to examine the phosphorylation of extracellular signalregulated kinase 1/2 (ERK1/2) andthe expression of proliferative cell nuclear antigen (PCNA), respectively. Results Granulation tissue appeared in the bed of wound after injury. The number of blood capillary buds and fibroblasts was greater in the rhPDGF-treated group than that in the other 2 groups. A lot of inflammatory cells infiltration and collagen deposition were observed in the wound. The wound-volume in the rhPDGF-treated group was smaller than that in control group (Plt;0.05). The reepithelialization rate in rhPDGF-treated group was higher than that inthe other 2 groups at 7 days after injury (Plt;0.05). The expression of PCNA in reparative cells was higher in rhPDGF-treated group than in control group or vehicle-treated group at 3,7 days after injury(Plt;0.05). The phosphorylation of ERK1/2 was ber in rhPDGF-treated group than that in control group or vehicle group at 7 and 14 days after injury(Plt;0.05). Conclusion These results suggest that rhPDGF accelerates wound healing and improves healing quality by increasingthe phosphorylation of ERK1/2.