As a temporary skin substitute, the dressings can protect the wound, stop bleeding, prevent infection and contribute to wound healing. According to the characteristics of the materials, wound dressings can be classified into traditional wound dressings, interactive dressings, bioactive dressings, tissue engineering dressings and smart dressings, etc. Different dressings have different characteristics, and some products have been widely used in clinic. Recently nanomaterials and three-dimensional bio-printing technology have significantly improved the performance of wound dressings. Future dressings will be developed from single function to multi-function composite, and integrated into an intelligent one. This paper reviews the current research progress and future development prospects of wound dressings.
ObjectiveTo investigate the effect of human adipose-derived stem cells (hADSCs) on pressure ulcers in mouse.MethodsThe subcutaneous adipose tissue from voluntary donation was harvested. Then the hADSCs were isolated and cultured by mechanical isolation combined with typeⅠcollagenase digestion. The 3rd generation cells were identified by osteogenic, adipogenic, chondrogenic differentiations and flow cytometry. The platelet rich plasma (PRP) from peripheral blood donated by healthy volunteers was prepared by centrifugation. The pressure ulcer model was established in 45 C57BL/6 mice by two magnets pressurized the back skin, and randomly divided into 3 groups (n=15). The wounds were injected with 100 μL of hADSCs (1×106 cells) transfected with a green fluorescent protein (GFP)-carrying virus, 100 μL human PRP, and 100 μL PBS in hADSCs group, PRP group, and control group, respectively. The wound healing was observed after injection. The wound healing rate was calculated on the 5th, 9th, and 13th days. On the 5th, 11th, and 21st day, the specimens were stained with HE staing, Masson staining, and CD31 and S100 immunohistochemical staining to observe the vascular and nerve regeneration of the wound. In hADSCs group, fluorescence tracer method was used to observe the colonization and survival of the cells on the 11th day.ResultsThe cultured cells were identified as hADSCs by induced differentiation and flow cytometry. The platelet counting was significantly higher in PRP group than in normal peripheral blood group (t=5.781, P=0.029). General observation showed that the wound healing in hADSCs group was superior to those in PRP group and control group after injection. On the 5th, 9th, and 13th days, the wound healing rate in hADSCs group was significantly higher than those in PRP group and control group (P<0.05). Histological observation showed that compared with PRP group and control group, inflammatory cell infiltration and inflammatory reaction were significantly reduced in hADSCs group, collagen deposition was significantly increased, and skin appendage regeneration was seen on the 21st day; at each time point, the expression of collagen was significantly higher in hADSCs group than in PRP group and control group (P<0.05). Immunohistochemical staining showed that the number of neovascularization and the percentage of S100-positive cells in hADSCs group were significantly better than those in PRP group and control group on the 5th, 9th, and 13th days (P<0.05). Fluorescent tracer method showed that the hADSCs could colonize the wound and survive during 11 days after injection.ConclusionLocal transplantation of hADSCs can accelerate healing of pressure ulcer wounds in mice and improve healing quality by promoting revascularization and nerve regeneration.
Objective To investigate the changes of transforming growth factor β1 (TGF- β1) and type Ⅱ of TGF-β-receptor (TβRⅡ) expressions in wound tissue after the treatment of diabetic foot with vaccum sealing drainage (VSD), and to analyze the mechanism of accelerating wound healing. Methods Between May 2012 and May 2016, 80 patients with diabetic foot were randomly divided into 2 groups, 40 cases in each group. After the same basic treatment, the wounds of VSD group and control group were treated with VSD and external dressing, respectively. There was no significant difference in gender, age, disease duration, body mass, foot ulcer area, and Wagner grade between 2 groups (P>0.05). The time of foundation preparation and hospitalization stay of 2 groups were recorded. The wound tissue was collected before treatment and at 7 days after treatment, and the positive indexes of TGF-β1 and TβRⅡexpressions were measured by immunohistochemical staining. Results Before skin grafting, the patients in VSD group were treated with VSD for 1 to 3 times (mean, 2 times), and the patients in control group were treated with dressing change for 1 to 6 times (mean, 4 times). The time of foundation preparation and hospitalization stay in VSD group were significantly shorter than those in control group (t=–13.546, P=0.036; t=–12.831, P=0.041). The skin grafts of both groups survived smoothly and the wound healed well. Before treatment, immunohistochemical staining results showed that the positive indexes of TGF-β1 and TβRⅡ expressions in VSD group were 5.3±2.4 and 14.0±2.6, while those in control group were 4.4±2.3 and 14.7±3.1, respectively. There was no significant difference between 2 groups (t=1.137, P=0.263; t=1.231, P=0.409). At 7 days after treatment, the positive indexes of TGF-β1 and TβRⅡ expressions in VSD group were 34.3±2.9 and 41.7±3.7, respectively, and those in control group were 5.8±2.0 and 18.1±2.5. There were significant differences between 2 groups (t=–35.615, P=0.003; t=23.725, P=0.002). Conclusion VSD can increase the expressions of TGF-β1 and TβRⅡ in diabetic ulcer tissue, promote granulation tissue growth, and accelerate wound healing.
In order to explore the effect of Sipunculus nudus extract (SNE) on skin wound healing in mice and its mechanism, hemostasis effect of SNE was measured, the mouse skin wound model was established by full-thickness excision. The morphological changes of the wound were observed after the treatment with SNE and the healing rate was measured. The changes of wound histology were observed by hematoxylin eosin (HE) staining, Masson staining and transmission electron microscope (TEM). The expression of cell factors and related proteins was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Results showed that the SNE possessed hemostatic function. SNE could obviously improve the healing rate of wound in mouse and shorten time of scab removal compared with the none-treatment (NT) group (P < 0.05).The pathological histology analysis results showed complete epidermal regeneration, with remarkable capillary and collagen fiber observed in the SNE group. The expression level of tumor necrosis factor-α (TNF -α), interleukin-1β (IL-1β) and transforming growth factor-β1 (TGF-β1) in SNE group was significantly lower than that of the NT group on 7 d (P < 0.05). Moreover, compared with the NT group, the gene expressions level of Smad7 was significantly increased and the level of type II TGF-β receptors (TGF-βRII), collagen I (COL1A1) and α-smooth muscle actin (α-SMA) were significantly reduced in the SNE group on 28 d (P < 0.05), but the difference was not statistically significant compared to Yunnanbaiyao group (PC group) (P > 0.05). These results indicated that SNE possessed obvious activity of accelerating wound healing and inhibiting scar formation, and its mechanism was closely related to hemostatic function, regulation of inflammatory factors, collagen deposition, collagen fiber remodeling and intervening TGF-β/Smads signal pathway. Therefore, SNE may have promising clinical applications in skin wound repair and scar inhibition.
Objective To observe the effect of radiofrequency ablation technology for the treatment of infected wounds in minipigs. Methods Infected wounds of full-thickness skin defects (about 6.15 cm2/wound) were prepared in 8 6-month-old minipigs (weighing, 30-35 kg) using the method of Davis et al. The 160 wounds were randomly divided into 4 groups (n=40). Infected wounds were debrided with the radiofrequency ablation technology in group A, with the electric knife in group B, and with the scalpel in group C; no treatment was done in group D as a control. The healing rate, healing time, and tissue filling rate were observed; bacterial quantitative examination and histological examination were done at 0, 2, 7, and 14 days after operation. Results All infected wounds were successfully established after 48 hours when Staphylococcus aureus dilution were inoculated. The wounds after radiofrequency ablation technology treatment were fresh and flat with slight bleeding; the healing time of group A was significantly shorter than that of groups B, C, and D (P lt; 0.05), and the healing rate of group A was significantly higher than that of groups B, C, and D at 7 and 14 days after operation (P lt; 0.05). The tissue filling rate of group A was significantly higher than that of groups B, C, and D at 2 days after operation (P lt; 0.05); the tissue filling rates of groups A, B, and C were significantly higher than that of group D at 7 and 14 days after operation (P lt; 0.05). At 0, 2, 7, and 14 days, there were significant differences in the bacterial count per gram tissue among 4 groups (P lt; 0.05), the order from low to high was groups A, B, C, and D. The histological observation showed that the surface of wound was smooth in group A at 0 day, and group A was better than the other groups in wound healing; at 2 days, some exudates were observed in 4 groups, but it was least in group A. There was inflammatory cell infiltration in various degrees in 4 groups at 7 and 14 days; it was lightest in group A with thick epithelium and dense collagen bundles, followed by groups B and C, and it was severe in group D. Conclusion The radiofrequency ablation technology can effectively remove the necrotic tissues of infected wounds, remarkably reduce the number of bacteria, improve the healing rate, and shorten the healing time of wounds.
Objective To summary the regulatory effect of mechanical stimulation on macrophage polarization in wound healing, and explore the application prospect of mechanical stimulation in tissue engineering. Methods The related domestic and foreign literature in recent years was extensive reviewed, and the different phenotypes of macrophages and their roles in wound healing, the effect of mechanical stimulation on macrophage polarization and its application in tissue engineering were analyzed. Results Macrophages have functional diversity, with two phenotypes: pro-inflammatory (M1 type) and anti-inflammatory (M2 type), and the cells exhibit different activation phenotypes and play corresponding functions under different stimuli. The mechanical force of different types, sizes, and amplitudes can directly or indirectly guide macrophages to transform into different phenotypes, and then affect tissue repair. This feature can be used in tissue engineering to selectively regulate macrophage polarization. Conclusion Mechanical stimulation plays an vital role in regulating macrophage polarization, but its specific role and mechanism remain ambiguous and need to be further explored.
摘要:目的:观察超短波治疗对痔术后创面愈合的影响。方法:将100例混合痔术后患者分为治疗组和对照组各40例,治疗组于术后24小时给予超短波治疗和复方紫草油纱条换药,对照组仅给以复方紫草油纱条换药,观察两组创面愈合时间和创面上皮生长速度。结果:治疗组较对照组创面愈合时间更短(Plt;0.01),创面上皮生长速度更快(Plt;0.01)。结论〗:超短波治疗能够加速痔术后创面愈合时间,减少痛苦,疗效确切安全。Abstract: Objective: To observe the clinical efficacy of ultrashort wave on the healing of wound after operation for hemorrhoids. Methods: One hundred cases of disease subjected to operation were divided into the treatment group (50 cases) and the control group (50 cases).The treatment group had been given ultrashort wave 24 hours after operation and Fufangzicaoyousa ointment gauze. The control group had been give Fufangzicaoyousa ointment gauze. Results: The results showed that the woundhealing time was much shorter in the treatment group than in the control group (Plt;0.01), the epidermis growth was much faster in the treatment group than in he control group (Plt;0.01). Conclusion: Ultrashort wave can promote the healing of wound after the operation for hemorrhoids and relieve pain, and it can be externally used safely.
OBJECTIVE The effect of platelet-derived wound healing factor (PDWHF) on wound healing in diabetic rats was studied. METHODS Forty-four male SD rats were randomly divided into 2 groups. Thirty-two rats of experimental group accepted intraperitoneal injection of alloxan (1.5 mg/10 g body weight). Within one or two days after injection, while the blood sugar of the rats was higher than 180 mg/dl, the animal model of diabetic rat should have been established. Then a dorsal incision was given to every rat. After the addition of PDWHF (the experimental group) or bovine albumin (the control group), the incision was sutured up. Seven, ten and fourteen days after operation, the breaking strength of the wound was measured. On another hand, specimen from the wound was taken for the culture of fibroblasts. When the cultured fibroblasts have been incubated with 10% PDWHF for 4, 8 and 12 hours, the procollagen I (alpha 1) mRNA levels were examined respectively, and compared with those of control. RESULTS Significant difference in wound breaking strength had been observed between PDWHF-treated incisions and the control on 7, 10 and 14 days after wounding (P lt; 0.01). Experiment in vitro demonstrated that the procollagen I (alpha 1) mRNA levels in wound fibroblasts incubated with 10% PDWHF for 4, 8 and 12 hours were 0.9, 3.7 and 2.2 folds higher than those in fibroblasts in control. CONCLUSION It was suggested that direct stimulation of procollagen I (alpha 1) gene expression was one of the ways that PDWHF played its role in accelerating wound healing.
Objective To prepare nerve growth factor (NGF)-insulin composite gel and observe the effects of NGF-insulin composite gel on deep second degree scald wound healing in diabetic rats. Methods Carbomer 980, NGF (4 000 U), and insulin (800 U) were used to prepare the insulin gel, NGF gel, and NGF-insulin composite gel. The character of NGF-insulin composite gel was observed, and the in vitro drug release was tested. Seventy-five SPF Wistar male rats, weighing 200-250 g, were divided into 5 groups randomly, 15 rats each group: normal control group (group A), diabetes control group (group B), insulin gel treatment group (group C), NGF gel treatment group (group D), and NGF-insulin composite gel treatment group (group E). The type 1 diabetes rat model was established by intraperitoneal injection of Streptozotocin (55 mg/kg) in groups B, C, D, and E, while the rats in group A were injected with the same dose of citric acid and calcium citrate buffer. After modeling success, deep second degree scald wound on the back was made with constant temperature water bath box. Wounds were treated with carbomer blank gel in groups A and B, with insulin composite gel in group C, with NGF gel in group D, and with NGF-insulin composite gel in group E, once a day. At 3, 7, 11, 15, and 21 days after injury, the scald wound healing was observed and healing rate was calculated; the full-thickness skin specimens were harvested from 3 rats of each group for histological and immuohistochemical staining observation. Results The NGF-insulin composite gel was clear and transparent, and had good moisture retention capacity and adhesion; it was easy to apply and clean up. The drug release in vitro lasted more than 24 hours and maintained for 30 days. No rat died during the experiment. At 3 days after injury, wound area did not reduce in all groups; at 7, 11, 15, and 21 days, group E had the highest wound healing rate, and group B had the lowest; significant differences were found between group E and group B and when compared with the other groups (P lt; 0.05). HE staining showed that group E surpassed other groups in the growth of granulation tissue and collagen fiber. Immunohistochemical results showed that the CD34 and proliferating cell nuclear antigen (PCNA) expressed at 3 days, and the number of positive cells increased gradually with time; the microvessel density and PCNA expression were highest in group E and were lowest in group B, showing significant differences when compared with the other groups and between group E and group B (P lt; 0.05). Conclusion NGF-insulin composite gel can improve deep second degree scald wound healing in diabetic rats.
We in the present study observed the effect of N-fructose modified chitosan quaternary ammonium derivativeson on rat skin wound healing through animal experiments. Forty rats were randomly divided into eight groups (5 in each group). Four groups among the all 8 groups were the experimental groups, while the other 4 groups were the control groups. Next to the skin along the back of the spine, 1.50 cm×2.00 cm×0.16 cm full-thickness skin was cut to make an excision wound model for every rat. Those in the experimental groups were treated with the N-fructose-modified chitosan quaternary ammonium derivatives ointment dressing the wound, while those in the control groups with sterile medical vaseline processing. We dressed the wounds twice a day to observe the wound healing of all rats in different groups. We then observed the wound healing and wound pathology after 3, 7, 10, 15 days respectively in different groups. Results showed significant differences of the time of wound healing, area of wound healing and volume of wound healing between the experimental groups and control groups (P<0.05). It can be well concluded that N-fructose-modified chitosan quaternary ammonium derivatives does not harm the skin, but could promote skin healing, so that they could be suitable skin repair materials and ideal raw materials for medical dressing.