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.
To evaluate the effects of bFGF on wound healing and the side-effects of bFGF, a multi-centers and controlled clinical trial were carried out in 32 hospitals in China. One thousand and twenty-four cases with acute wounds such as burn, donor site or operative wound and chronic wounds such as bed sore, draining sinus, ulcer were treated with bFGF. Another 826 cases with the similar wounds were used as control. The results showed: 1. The duration of wound healing was shorted 3-4 days in trial group when compared with the contorl; 2. The successful rates from bFGF on promoting the wound healing for burns, operative wounds and chronic dermal ulcers was 95.2%, 96.5% and 93.5%, respectively; 3. No adverse reaction was found. CONCLUSION: 1. bEGF can make the "silent" reparative cells dividing and proliferating. 2. bFGF can improve the quality and the velocity of wound healing.
Objective To observe the effect of angiotensin Ⅱ (Ang Ⅱ) or/and transforming growth factor β(TGF-β) on human skin fibroblast proliferation, and to explore the possible signaling mechanism involved in their actions. Methods Cultured human skin fibroblasts were treated with different concentrations of Ang Ⅱ (1×10-10 , 1×10-9，1×10-8 and 1×10-7 mol/L) , TGF-β(0.1, 1.0 and 10.0 ng/ml), and 1×10 -10 mol/L Ang Ⅱ＋0.1 ng/ml TGF-β, respectively. The cell proliferation was determined by3Hthymidine (3H-TdR) incorporation. The phosphorylation of extracellular signalregulated kinases (ERK) was detected by Western blot. Results Ang Ⅱ at 1×10-9，1×10-8，1× 10-7 mol/L or TGF-β at 1.0, 10.0 ng/ml increased 3H-TdR incorporation into cultured skin fibroblasts dose-dependently. Ang Ⅱ and TGF-β at lower doses (1×10-10 mol/L and 0.1 ng/ml, respectively) did not affect 3H-TdR incorporation into fibroblasts (Pgt;0.05), whereas co-administration of both Ang Ⅱ and TGF-β at these doses significantly increased 3H-TdR incorporation intofibroblasts(Plt;0.05). Ang Ⅱ at 1×10-7 mol/L or TGF-β at 10.0 ng/ml significantly increased ERK phosphorylation of fibroblasts after stimulation (Plt;0.01). Smaller doses of Ang Ⅱ (1×10-10 mol/L) or TGF-β (0.1 ng/ml) did not influence ERKphosphorylation of fibroblasts, whereas co-administration of Ang II and TGF-β at these doses significantly enhanced ERK phosphorylation (Plt;0.05). Total protein levels of ERK did not differ at different doses. Conclusion These results indicate that Ang Ⅱ and TGF-β synergistically increase skin fibroblast proliferation, which is at least partly via enhancement of ERK activity.
Objective To investigate the influence of lipopolysaccharide(LPS) on the proliferation and collagen synthesis of normal human skin fibroblasts so as to elucidate its relation with skin wound healing. Methods Fibroblasts wereisolated and cultured in vitro, and then exposed to different doses of LPS(0.005, 0.010, 0.050, 0.100, 0.500, and 1.000 μg/ml) from E.coli055∶B5 respectively. Then the absorbance (A) value of fibroblasts was determined with the colorirneteric thiazolylblue (MTT) assay, and the cell number was counted under inverted phase contrast microscope from the 1st day to the 9th day after LPS administration, and collagen synthesis of fibroblasts in culture medium was measured with the method of pepsin digestion after incorporation of 3Hproline into stable, single-layered, confluent fibroblasts at 7 days after LPS administration. Results Compared with control group, A value increased with the increasing concentration of LPS (0.005 μg/ml 0.500 μg/ml) and LPS of 0.100 μg/mlgroup had the best effect. The difference was remarkable from the 5th day to the 9th day(P＜0.05). A value decreased when challenged with the LPS of 1.000 μg/ml and the difference was remarkable from the 3rd day to the 9th day(P＜0.05). Cell number increased with theadministration of LPS of different concentrations (0.005 μg/ml 0.500 μg/ml) and LPS of 0.100 μg/mlgroup had the best effect. The difference was remarkable from the 1st day to the 6th day(P＜0.05). Cell number decreased remarkably when challenged with LPS of 1.000 μg/ml and the difference was remarkable from the 2nd day to the 9th day(P＜0.05). Collagen synthesis increased when challenged with LPS of different concentrations (0.005 μg/ml 0.500 μg/ml) and the 0.100 μg/ml group had the best effect. However, when the dose of LPS reached 1.000 μg/ml, it inhibited collagensynthesis. Conclusion LPS could promote the proliferation andcollagen synthesis of fibroblasts within a certain range of low doses, but over-high dose ofLPS might inhibit the proliferation and collagen synthesis of fibroblasts, suggesting that LPS of certain concentrations might contribute to wound healing, while excessive LPS has negative effect on wound healing.
Objective To investigate the cl inical effect of vacuum seal ing drainage (VSD) on late-stage large skin avulsion injury with infection. Methods From May 2007 to August 2008, 9 patients with large-area skin avulsion injury and infection were treated. There were 1 male and 8 females aged 9-52 years old (median 27 years old). All patients suffered from closed skin avulsion injury involving the lower back, buttock, and part of the thigh. The injury area varied from 30 cm × 25 cm to92 cm × 38 cm. The time between injury and hospital admission was 15-23 days. The skin avulsion injury was compl icated with pelvis fracture, urethral injury, anal injury, sacrum exposure, and l imb fractures. The interval between hospital admission and operation was 3-23 hours. Free spl it-thickness skin graft was performed after the focus debridement and three VSD treatments (40-60 kPa). Results After three VSD treatments, no patient had general pyemia and severe local tissue necrosis or infection, the tissue edema in the skin avulsion area was alleviated obviously, and all the wound cavities were closed. All the wounds in the graft site healed after 28-45 days of treatment (average 39 days), and all the donor sites healed. Nine patients were followed up for 4-14 months (average 10 months). The appearance of the reparative area was good, and there was no occurrence of joint dysfunction in the injured area due to scar contracture. Conclusion VSD is effective in treating late-stage large skin avulsion injury with infection.
Objective To probe the effects of lumbricus on wound healing after hemorroidectomy.Methods After the solution made from artificial grown lumbricus was sprung to the wound of animal and patient after hemorroidectomy, the wound inflammation, wound healing and changes of laboratory determinations were observed and compared to those of the control group. Results In animal study, lumbricus could inhibit the growth of staphylococci, bacillus coli and bacillus aeruginosus. The time of wound healing in experimental group was 4 days shorter than that in control group. At 4d and 7 day the numbers of the capillary, blood vessel endodermis and desmohemoblast desmocyte and splitting epithelium of trial group were much more than those of control group. At 4d the trial group′s numbers of splitting mesenchymal cell were much more than that of control group. From 3d on the wound healing and granulation filling of experimental group were much quicker than those of control group. In clinical study, the time of wound healing of trial group ( a mean of 16.5 days) was shorter than that of control group (21.2 days). From 3d on, the epidermis′ growth speed of the trial patients was much quicker than that of control group and was without wound infection and granulation overproliferation. Conclusion Lumbricus can inhibit wound inflammation response and accelerate wound healing. Lumbricus is inexpensive and easily preserved, and could be used on the wound after hemorroidectomy to accelerate wound healing.
Objective To investigate the effect of hydrochloric propranolol cream and its possible mechanism on wound healing in diabetic mice. Methods Eighteen 8-week-old BKS.Cg-Dock7m+/+Leprdb/JNju diabetic mice were randomly divided into control group (n=9) and experimental group (n=9). After full-thickness dermal wounds (0.6 cm in diameter) was made, wounds were treated with cream containing hydrochloric propranolol (experimental group) or not containing hydrochloric propranolol (control group) at 2, 5, 7, 10, 14, and 17 days. At 2, 5, 7, 10, 14, 17, and 21 days, wound healing was observed, and healing rate was calculated; HE staining, Masson staining, and toluidine blue staining were used to observe wound re-epithelialization, collagen fibers, and mast cells distribution. Western blot was applied to detect the expressions of interleukin 1β (IL-1β) and angiogenin 2 (Ang2) in wound tissue. Results Wounds healed in 2 groups, but the wounds healing rate of experimental group was significantly higher than that of control group at other time points (P < 0.05) except 21 days (P > 0.05). The histological observation showed that re-epithelialization rate was higher in experimental group than control group, there were less mast cells in the wound. The experimental group was lower than control group in IL-1β expression at 2, 5, 7, 14, 17, and 21 days and in Ang2 expression at 2, 5, 7, 10, 14, 17, and 21 days. Conclusion Hydrochloric propranolol cream can promote wound healing in diabetic mice, which potential mechanism is that propranolol can promote epidermal cell proliferation, reduce inflammation, and benefit angiogenesis.
OBJECTIVE: To explore the expression of basic fibroblast growth factor(bFGF) during the wound healing of human fetal and adult skin and its significance. METHODS: We established the animal model of fetal scarless healing by transplanting full-thickness skin grafts from human fetus to a subcutaneous location on the athymic mouse recipient, and then making the linear incisions. The expression of bFGF was observed in the normal adult skin, normal fetal skin and during wound healing by immunohistochemical method. The positive staining cells were counted under selected high-power focus randomly. RESULTS: bFGF staining was not observed in the normal fetal skin and the wounded one. However, bly positive staining was shown around the vessels in normal adult skin. Moreover, the positive straining became ber in the wounded skin, especially in dermal fibroblasts and endotheliocytes. The number of positive staining cell was 2.1 +/- 0.1 in normal fetal skin, and 2.2 +/- 0.1, 2.1 +/- 0.3, 2.1 +/- 0.3 and 2.0 +/- 0.1 in the fetal skins after 12 hours, 1 day, 3 days and 7 days of wound respectively. The number of positive staining cell were 23.2 +/- 4.2 in normal adult skin and 40.5 +/- 3.6 in the wound adult skin. There was significant difference between the fetal skin and adult skin (P lt; 0.01). CONCLUSION: The negative expression of bFGF in the fetal skin may be one of the important reasons for fetal scarless healing.
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.
Objective To compare the clinical effect between alginate calcium dressing and radix yarn dressing after anal fistula surgery. Methods A survey of 128 patients with anal fistula from April to October 2008 were studied. Patients were divided into two groups using a simple random method: 64 cases in therapy group which were treated with alginate calcium dressing and 64 cases in control group which were treated with traditional radix yarn dressing. The difference of the wound recovery indexes between two groups was compared.Results With regard to age, gender, anal fistula type, the proportion of preoperative diabetes and the diameter of wound, there was no statistical significance between therapy group and control group (Pgt;0.05). The proportion of slight pain during dressing change in therapy group (45.32%, 29/64) was more than control group (25.00%, 16/64), which had statistical significance (Pgt;0.05). The incidence of skin allergy was significantly different between two groups (29.69% vs. 60.94%, P＜0.05). Also, the rotten tissue and the soakage disappears with a shorter period, which both had statistical significance 〔(8.60±2.37) d vs. (12.22±3.29) d， (16.96±5.83) d vs. (22.02±5.90) d〕， Plt;0.05.Conclusion With the shorten of inflammatory and increment stage of the wound recovery, alginate calcium dressing is an ideal material for the postoperative duration of surgery of anal fistula.