Objective To compare and research the process of woundhealing in occlusive moist environment and dry environment on the skin donor site. Methods The wound healing of adult skin donor site was studied by clinical observation, histological and electromicroscopical examinations on the operative day and the 1st, 2nd, 3rd, 4th, 7th days postoperatively, each skin donor site was divided into two parts: occlusive environment and dry environment. Results The wounds of occlusive moist environment healed faster than those of dry environment; thefibroblasts were more active and activated earlier, revascularization and re-epithelialization happened earlier and more quickly. Conclusion In occlusive environment, more active fibroblasts can accelerate granulation growth; quicker regenerative capillaries bring more nourishment; quicker re-epithelialization accelerates the wound healing.
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.
ObjectiveTo investigate the effect of platelet rich plasma (PRP) in promoting wound healing of total hip arthroplasty (THA). MethodsBetween January 2011 and January 2012, 80 patients scheduled for THA and accorded with the inclusion criteria were divided into 2 groups:wounds were treated with PRP in 40 patients (PRP group) and with normal saline in 40 patients (control group). There was no significant difference in gender, age, disease duration, injury causes, sides, fracture type, and preoperative Harris hip scores between 2 groups (P>0.05). Routine drainage and functional exercise were performed after operation. ResultsThe postoperative drainage volume of PRP group[(137±26) mL] was significantly lower than that of control group[(424±39) mL] (t=38.726, P=0.000). At 4 days after operation, no inflammatory reaction was observed in 34 cases of PRP group and in 30 cases of control group, mild inflammatory reaction in 5 cases of PRP group and in 6 cases of control group, moderate inflammatory reaction in 1 case of PRP group and in 4 cases of control group; there was no significant difference between 2 groups (χ2=2.141, P=0.343). Wound healed by first intention in 40 patients of PRP group and in 39 patients of control group, showing no significant difference between 2 groups (P=1.000). The average follow-up period was 9 months (range, 6-12 months). The Harris hip scores of PRP group (90.2±2.5) and control group (89.3±3.1) at last follow-up were significantly better than those before operation (39.6±8.9 and 39.2±9.2 respectively) (t=34.618, P=0.000; t=32.638, P=0.000), but no significant difference was found between 2 groups (t=1.429, P=0.153). ConclusionUsing PRP in THA wound can reduce postoperative drainage volume, improve the healing of operation incision. It is a safe, effective, and promising procedure in treatment of THA wound.
Objective To investigate the effect of leptin on fibroblast proliferation and collagen synthesis as to elucidate that fibroblasts play a role in leptin’s effect on wound healing. Methods Purified dermal fibroblasts were derived from sucking wistar rat skin and exposedto leptin at concentration of 0, 10, 50, 100, 200, and 400 ng/ml. The survived fibroblasts were assessed by the colorimetric thiazolyl blue (MTT) assay. Replication of fibroblast was quantified by the incorporation of 3H-thymidine. Collagen synthesis of fibroblast cell was measured by the incorporation of 3H-proline into collagenasesensitive protein. Results The absorption of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 0.082±0.013, 0.091±0.018 was higher than that of control group 0.063±0.010, P＜0.05. The incorporations of 3H-thymidine of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 379±101 cpm,326±33 cpm were significantly higher than those of control group 219±56 cpm, P＜0.05. The incorporations of 3H-proline of fibroblast exposed to leptin at concentration of 200 and 400 ng/ml 911±55 cpm, 1 072±259 cpm were significantly higher than that of control group 679±176 cpm, P＜0.05. Conclusion Leptin can promote rat cutaneous fibroblast proliferation and collagen synthesis in vitro. This suggests that cutaneous fibroblast plays a role in leptin’s promoting skin wound healing and it may be one of the main mechanisms by which leptin enhances skin wound healing.
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.
ObjectiveTo investigate the mechanism of impeded wound healing by exogenous hyaluronan (HA). Methods Wound healing models were established on 18 adult rabbit ears, which were randomly divided into 3 groups, the 2% HA treated-group (group A), the 1% HA treated-group(group B), and the PBS control-group (group C). The process of wound healing was observed morphologically and histologically. The expression of α-smooth muscle actin in fibroblast was measured by immunohistochemical method. Results ①The mean values of wound healing time of groups A, B and C were (11.7±0.6), (11.3±0.6), and (10.8±1.0) days respectively. Wound contraction was greater in group C than in group A and group B. ②Compared with PBS controls, the collagen fibril was slender and arrayed regularly in HA treated wound. ③ The expression of α-smooth muscle actin was greater in group C than in groups A and B. Conclusion It is one of reasons of impeded wound healing that exogenous HA inhibits the expression of α-smooth muscle protein and wound contraction. There exists dose-dependant effect.
OBJECTIVE: To investigate the effects of trace elements on the metabolism of extracellular matrix and explore the physiological and pathological mechanism of trauma. METHODS: Based on the experimental and clinical data, it was studied that the action of trace elements in the metabolism of extracellular matrix in trauma repairing. RESULTS: During wound healing, the trace elements were the components of many kinds of enzymes, carriers and proteins. They took part in the synthesis of hormones and vitamins as well as the transmission of information system. They activated many different kinds of enzymes and regulate the levels of free radicals. The trace elements had the complicated effects on the synthesis, decompose, deposition and reconstruction of collagen and other extracellular matrix. CONCLUSION: The trace elements play an important role in regulating the metabolism of extracellular matrix.
OBJECTIVE: To set up some objective and accurate criteria to evaluate wound healing. METHODS: Documents about wound healing were reviewed and summarized in detail. RESULTS: Wound healing rate, wound healing time, histopathology analysis, quantity assay of macrophage, determination of hydroxyproline, proliferation of cell, assay of DNA contents and circle of cells, level of transforming growth factor-alpha, levels of interleukin-1, interleukin-6 and tumor necrosis factor, assay of keratinocyte collagenase-1, level of fibroblast growth factor receptor-1, level of monocyte chemoattractant protein-1 and level of keratinocyte plasminogen activator inhabitor type 2 were selected as the evaluation criteria of wound healing. CONCLUSION: Wound healing rate, wound healing time and histopathology analysis are direct and efficient criteria of wound healing.
Objective To compare the reparative effects between the acellular small intestinal submucosa andthe acellular amnion as dressings for traumatic skin defects. Methods Three full-thickness skin defects, which wereclose to the vertebral column of the pig, were created on both sides of the dorsum. The skin defects were randomlydivided into three groups. In each group, the following different materials were used to cover the skin defects: theacellular amnion in Group A, the acellular small intestinal submucosa (SIS) in Group B, and the physiological saline aguze in Group C (the control group). The specimens from the skin defects were harvested for a histological evaluation and for determination of the hydroxyproline content at 10 (2 pigs), 20 (2 pigs), and 30 days (3 pigs). We observed the healing process of the wound and its healing rate, counted the inflammatory cells, vasecular endothelial cells, and proliferating cells, and determined the hydroxyproline content. Results The acellular amnion in Group A and acellular SIS in Group B adhered to the wound tightly, but they did not adhere to the dressing; when the dressing was changed, the wound did not bleed. The saline gauze in Group C adhred to the wound tightly, but when the dressing was changed, the wound bled until 22 days after operation. Under the microscope, the collagen in the tissue below the epithelium was arranged more regularly and there were fewer cells concerned with inflammation in Groups A and B than in Group C at 10, 20, and 30 days after operation. At 10, 20, and 30 days after operation, the wound healing rate was greater in Groups A and B than in Group C, The number of the inflammatory cells and the proliferating cells were greater in Groupo C than in Groups A and B. There was a statistically significant difference (P lt; 0.05),At 20 and 30 days after operatin, the content of hydroxyproline was greater in Group c than in Group A and B. There was a statistically significant difference (P lt; 0.05). However, there was no statistically significant difference between Group A and Group B in the wound healing rate, the numbers of the inflammatory cells, vascular endothelial cells and prokiferating cells, and the content of hydroxyproline(P gt; 0.050). There was no statistically significant difference among the three groups in the number of the vascular endothelial cells. Conclusion Compared with Group C........
Objective To construct a bioengineered dermis containing microencapsulated nerve growth factor (NGF) expressing -NIH3T3 cells and to study the effect of the microencapsule on the bioengineered dermis and acute wound healing. Methods A recombinant NGF (PcDNA3.1+/NGF) was constructed and transfected intoNIH-3T3 cells using FuFENETM6 transfection reagent. Positive cell strain was cultured and enclosed in alginate-polylysine-alginate(APA) microcapsules in vitro. Bioengineered dermis was incorporated with NGF-expressing micorencapsules and human fibroblast cells as seed cells using tissue engineering method. The characteristics of the dermis were described by the content of Hydroxyproline(Hyp), HE staining. The content of NGF in the dermis culturing supernatant was measured by ELISA method. These bioengineered dermis were transplanted onto the acute circular full thickness excisional wounds on the dorsum of each swine to observe the rate of reepithelization and wound healing: NGFNIH3T3 microencapsulations(group A), NIH3T3 microencapsulations( group B), empty microencapsulations (group C), NGF incorporated with collagenⅠ( group D) and blank (group E as control group). Results NGF can be tested stably about 124.32 pg/ml in the dermis culturing supernatant after 6 weeks, and the content of Hyp in group A was 69.68±6.20(mg/g wet weight) and increased about 2 times when compared with control groups after 1 week. The tissue engineering skin grafts which can secrete NGF were used to ure the acute wounds and the rate of reepithelization was promoted. The periods of wound healing were 25±2 days in group A, 34±3 days in group B, 34±2 days in group C, 33±2 days in group D and 40±3 days in group E.The period of wound healing was decreased about 10 days at least. Conclusion NGF-expressing NIH3T3 microencapsulates can promote the quality of bioengineered dermis and alsopromote acute wound healing.