Objective To evaluate the efficacy and safety of acellular dermal matrix (ADM) in preventing Frey syndrome.Methods Studies of acellular dermal matrix in preventing Frey syndrome were searched in The Cochrane Library (Issue 1, 2010), MEDLINE, EMbase, SIGLE, GreyNet, NTIS, CBMdisc, VIP, CNKI and WANFANG DATA from 1995 to 2010. All the studies were selected, extracted and evaluated by four reviewers independently, and meta-analyses were performed with RevMan 5.0.0 software. Results A total of 15 studies involving 472 participants were included in the review. The studies showed that implantation of the ADM was able to efficiently reduce the incidence of Frey syndrome, and the difference in both subjective and objective was significant between the two groups after the therapy (RR=0.11, 95%CI 0.06 to 0.18, Plt;0.01; RR=0.14, 95%CI 0.10 to 0.19, Plt;0.01). The rate of temporary facial nerve paralysis was lower than that of the control group but the difference was not significant (OR=0.78, 95%CI 0.37 to 1.66, P=0.53). The incidens of both seroma and mucocele were higher than that of the control group but the difference was not significant(OR=2.63, 95%CI 0.09 to 79.25, P=0.58) and they could be alleviated by placing drainage tube and partial pressure bandage. The incidence rate of salivary fistula was lower than that of the control group and the difference was significant (OR=0.24, 95%CI 0.08 to 0.69, P=0.009). Conclusion The result of this system review shows that, the ADM can effectively and safely reduce the incidence of Frey syndrome. To perform preoperative hypersensitivity check for iodine or iodophors, to conduct rapid frozen section for defining the character of tumor, to fix the ADM stably, to place vacuum-drainage and to make partial pressure bandage are suggested.
Objective To investigate the effectiveness of endoscopic low-temperature plasma radiofrequency ablation with acellular dermal matrix patch for chronic abdominal wall sinus by comparing with the traditional surgical method. Methods Retrospective analysis was made on the clinical data of 53 cases of chronic abdominal wall sinus between January 2006 and May 2012. Of 53 patients, 18 underwent endoscopic low-temperature plasma radiofrequency ablation with acellular dermal matrix patch (trial group), and 35 underwent traditional surgical treatment (control group). No significant difference was found in gender, age, etiology, disease duration, and location between 2 groups (P gt; 0.05). Results The blood loss during sinus clearance, postoperative hospitalization days, and sinus union time of the trial group were significantly better than those of the control group (P lt; 0.05), but no significant difference was found in the operative time for sinus clearance (t=0.28, P=0.78). No postoperative sinus bleeding or infection occurred in the trial group, but bleeding and infection in 5 and 3 cases of the control group respectively, showing significant differences between 2 groups (P lt; 0.05). The follow-up time was 4-18 months (mean, 12.4 months) in the trial group, and was 6-48 months (mean, 38.5 months) in the control group. No sinus recurrence was observed during follow-up. Conclusion Endoscopic low-temperature plasma radiofrequency ablation with acellular dermal matrix patch has the following advantages in treating chronic abdominal wall sinus: clear view, thorough cleaning of granulation necrosis tissues, less bleeding, faster sinus union, and shorter hospitalization days; however, further observations on the long-term effectiveness and the safety are required .
【Abstract】 Objective To investigate the impact of dermal papillary cells on vascularization of tissue engineered skinsubstitutes consisting of epidermal stem cells and allogeneic acellular dermal matrix. Methods Human foreskins from routinecircumcisions were collected to separate epidermal cells by using dispase with trypsogen. Collagen type IV was used to isolateepidermal stem cells from the 2nd and 3rd passage keratinocytes. Dermal papilla was isolated by the digestion method of collagenaseI from fetus scalp and cultured in routine fibroblast medium. Tissue engineered skin substitutes were reconstructed by seedingepidermal stem cells on the papillary side of allogeneic acellular dermis with (the experimental group) or without (the controlgroup) seeding dermal papillary cells on the reticular side. The two kinds of composite skin substitutes were employed to cover skindefects (1 cm × 1 cm in size) on the back of the BALB/C-nu nude mice (n=30). The grafting survival rate was recorded 2 weeks aftergrafting. HE staining and immunohistochemistry method were employed to determine the expression of CD31 and calculate themicrovessel density at 2 and 4 weeks after grafting. Results Those adhesion cells by collagen type IV coexpressed Keratin 19 andβ1 integrin, indicating that the cells were epidermal stem cells. The cultivated dermal papillary cells were identified by expressinghigh levels of α-smooth muscle actin. The grafting survival rate was significantly higher in experimental group (28/30, 93.3%), thanthat in control group (24/30, 80.0%). HE staining showed that the epithelial layer in experimental group was 12-layered with largeepithelial cells in the grafted composite skin, and that the epithelial layer in control group was 4-6-layered with small epithelial cells.At 2 and 4 weeks after grafting, the microvessel density was (38.56 ± 2.49)/mm2 and (49.12 ± 2.39)/mm2 in experimental group andwas (25.16 ± 3.73)/mm2 and (36.26 ± 3.24)/mm2 in control group respectively, showing significant differences between 2 groups(P lt; 0.01). Conclusion Addition of dermal papillary cells to the tissue engineered skin substitutes can enhance vascularization,which promotes epidermis formation and improves the grafting survival rate.
Objective To evaluate the effect of tissue engineered skin with isogeneic cells on repairing skin defects in inbred rat model so as to provide relevant evidences for the clinical application. Methods The skins of newborn inbred F344 rats were harvested and treated with Dispase trypsin to isolate the epidermal cells. The skins of adult Sprague Dawley rats were obtained and treated with hypertonic sodium-SDS-trypsin to prepare the acellular dermal matrix. The tissue engineered skin was reconstructed by submerging culturing and air-liquid interface culturing in vitro. The full-thickness skin defects of 1.5 cm × 1.5 cm in size were prepared along the dorsal both sides of 36 adult inbred F344 rats, and 72 defects were repaired with tissue engineered skin in experimental group (n=24), with allogeneic acellular dermal matrix in negative control group (n=24), and with autologous full-thickness skin in positive control group (n=24). Finally the gross observation, the survival rate, wound contraction rate, and histological observation were used to evaluate the effect. Results The wound healed by first intension at 4 weeks postoperatively in the experimental group; the grafts connected with the adjacent tissue tightly and had normal appearance. At 4 weeks after operation, the survival rate of the graft was 0 in the negative control group; the survival rates were 62.5% (15/24) in the experimental group and 91.7% (22/24) in the positive control group, showing significant difference between 2 groups (χ2=5.779, P=0.016). The wound contraction rates of the experimental group and positive control group were significantly lower than that of the negative control group (P lt; 0.05), but no significant difference was found between the experimental group and positive control group (P gt; 0.05). Histological observation showed that slight inflammation reaction appeared at 1 week postoperatively in the experimental group; the regeneration of the blood vessel and the proliferation of the fibroblasts in dermis and the gradual maturation of epidermis were observed at 2 weeks, and new collagen deposition and collagen remodeling in the dermis of the graft were found at 4 weeks postoperatively. Conclusion The tissue engineered skin is able to repair full-thickness skin defect of rats effectively, it has similar effect to the autologous full-thickness skin in preventing the wound contraction and promoting the wound healing, which provides experimental evidences for the clinical application.
Objective To research the effect of porcine acellular dermal matrix in the reconstruction of abdominal wall defects in rabbits, and to investigate the appl ication feasibil ity of xeno-transplantation of acellular dermal matrix. Methods The porcine acellular dermal matrix was prepared from a health white pig. Twenty-six Japanese white rabbits (weighing 2.2-2.3 kg, female or male) were randomly assigned to 2 groups: the control group (n=6) and the experimental group (n=20). In the control group, the full-thickness abdominal wall defect of 5.0 cm × 0.5 cm was made, and the defect wassutured directly; in the experimental group, the full-thickness abdominal wall defect of 5.0 cm × 2.5 cm was made, and the defect was repaired with porcine acellular dermal matrix patch at the same size as the defect. At 5 weeks after surgery, the incidence of hernia and the intra-abdominal adhesions were observed and the wound breaking strength was compared between the patchfascia interface and the fascia-fascia interface. The graft vascularization was evaluated through histological analysis at 6 months after surgery in the experimental group. Results No hernia occurred in all rabbits of 2 groups. At 5 weeks after surgery, heal ing was observed between patch and the muscularfascia; the vascularization was seen in the porcine acellular dermal matrix patch. There was no significant difference in the adhesion grade (Z= —0.798, P=0.425) between the experimental group (grade 2 in 1 rabbit, grade 1 in 5, and grade 0 in 12) and the control group (grade 1 in 1 and grade 0 in 5). No significant difference was found (t= —0.410, P=0.683) in the breaking strength between the patch-fascia interface in the experimental group [(13.0 ± 5.5) N] and the fascia-fascia interface in control group [(13.6 ± 4.0) N]. In the experimental group, the small vessels and the infiltration of inflammatory cells were observed in the porcine acellular dermal matrix patch after 5 weeks through histological observations. The junctions of the patch-fascia interface healed with fibrous connective tissue. At 6 months after surgery, the inflammation was subsided and the collagen fiber of the patch was reconstructed. Conclusion The porcine acellular dermal matrix patchhas good results in repairing full-thickness abdominal wall defect. The patch-fascia interface has siml iar breaking strength to the fascia-fascia interface. The collagen fibers of the patch are reconstructed.
Objective To compare the effect of the composite skin graft consisting of spl it-thickness skin grafts (STSGs) and porcine acellular dermal matrix (PADM) with STSGs only, and to histologically observe the turnover of the PADM in rats. Methods Twenty female Sprague-Dawley rats, weighing 200-225 g, were included. The size of 4.0 cm × 2.5 cm PADM was implanted into hypoderm of the left side of Sprague-Dawley rats’ back. After 10-14 days, the size of 4.0 cm × 2.5 cm full-thickness skin defects were made on the left to expose the PADM under the skin and the same size of full-thickness skin defects were made on the right of the rats’ back. The excised full-thickness skin was made to STSGs about 0.2 mm by drum dermatome. The defects were grafted with composite skin (STSGs on the PADM, experimental group) and STSGs only (control group). The survival rate, the constraction degree of grafts, and the histological change in grafts area were observed at 2, 4, 8, and 20 weeks after operation. Results At 2 weeks after STSGs (0.2 mm) placed on vascularized PADM, STSGs and PADM adhered together and the composite skin had a good survival. The control group also had a good survival. Histological observations showed that STSGs and PADM grew together, neutrophil ic granulocytes and lymphocytes infiltrated in the PADM and some macrophages around the PADM. Fibrous connective tissues were filled under the STSGs in control group. At 4-8 weeks after transplantation, the composite skin had a good survival and the composite skin was thick, soft, and elastic. STSGs survived almost totally in control group, but the grafts were thin. Histological observations showed that inflammatory reactions of PADM faded gradually in experimental group; scar tissues formed under the STSGs in control group. At 20 weeks after transplantation, composite skin was flat, thick, and elastic in experimental group, but the STSGs were thinner and less elastic in control group. Histological observations showed that histological structures of the PADM were similar to the dermal matrix of rats, and the results showed that the collagen matrix of PADM was gradually replaced by the rats’ collagen matrix. Scar tissues were filled under the STSGs in control group. Wound heal ing rates of experimental group were lower than those of control group at 4 and 8 weeks (P﹤0.05); wound contraction rates of experimental group had lower tendency than those of control group, but showing no significant differences (P gt; 0.05). Conclusion Coverage wound with composite skin which composed of STSGs and PADM could improve wound heal ing qual ity; the composite skin is thicker and better elastic than STSGs only. The collagen matrix of PADM is gradually replaced by rats’ collagen matrix.
Objective To summarize the cl inical effect of allogenic acellular dermal matrix in repair of abdominal wall hernia and defect. Methods The cl inical data were analyzed retrospectively from 31 patients with abdominal wall hernia and defect repaired by allogenic acellular dermal matrix between March 2007 and November 2009. There were 19 males and 12females with an age range of 10-70 years (median, 42 years), including 6 abdominal wall defects caused by abdominal wall tumor resection, 4 patchs infection after abdominal wall hernia repair using prosthetic mesh, 2 incisional hernia, 1 parastomal hernia, 1 recurrent parastomal hernia receiving mesh repair, 1 mesh infection caused by parastomal hernia repair using prosthetic patch, 3 mesh infection caused by tension free inguina after hernia repair, and 13 inguinal hernia. There were 12 patients with contaminated or infectious wound. The disease duration was from 1 to 34 months (6 months on average). The defect size of abdominal wall ranged from 6 cm × 4 cm to 19 cm × 10 cm. Abdominal wall hernia or defect underwent repair using allogenic acelluar demall matrix. Results Of the 31 patients, 29 patients recovered with primary wound heal ing. Chronic sinus tract occurred in 1 patient and the wound was cured by change dressing. Wound dehiscence and patch exposure occurred in 1 patient, and second heal ing was achieved after change dressing. All the 31 patients were followed up 6-36 months, no abdominal wall hernia or hernia recurrence occurred in other patients except 1 patient who had abdominal bulge. And no foreign body sensation or chronic pain in wound area occurred. Conclusion It is feasible and safe to use allergenic acellular dermal matrix patch for repair of abdominal wall hernia or soft tissue defect, especially in contaminated or infectious wound.
【Abstract】 Objective To introduce the cl inical appl ication of heterogeneity (cattle) acellular dermal matrix(ADM)in the repair of mucosa defect otolaryngology. Methods From October 2006 to March 2007, 12 cases of mucosa defect was repaired with heterogeneity ADM after the surgery. There were 10 males and 2 females, aged 18-76 years. Defect was caused by deflection of nasal septum in 1 case, melanoma of front and midst basal is (capillary hemangioma) in 1 case, nasal vestibule angioma (T2N2M0)in 1 case, cancer of hypopharynx (T2N1M0) in 1 case, cancer of amygdale in 3 cases (2 of T2N0M0 and 1 of T3N1M0),cervical segments esophageal carcinoma in 1 case, and cancer of larynx in 4 cases (3 of T2N0M0 and 1 of T3N1M0). Results All these 12 cases were followed up for 6 months. The results of endoscope showed that heterogeneity ADM mingled with mucosa within 3 months after operation and the function was recovered. Pharynx fistula occurred in 1 case of hypopharynx cancer afterthe operation. After treatment of dressing change and antibiotics for 10 days, the wound healed, but after 2 months tumor recurred. All the patients were treated by radiation treatment. One case of amygdala cancer recurred and transferred to the neck after 2 months of radiation treatment. But 1 case of hypopharynx cancer died of massive haemorrhage after radiation treatment for 3 months. Conclusion Heterogeneity ADM can be easily obtained and it is a new method to repair mucosa defect. Theoperative procedure is easy to perform and worthwhile to be appl ied to cl inical operation.
Objective To investigate the effect of ultra-filtration on reducing the matrix effects of the immersionof recombination human acellular dermal matrix (rhADM) on detecting residual bovine serum albumin (BSA) by ELISA.Methods Preparation of rhADM immersion: rhADM were rinsed, and then rhADM immersion were prepared. Physiologicalsal ine was used as immersion medium. Presaturation and ultra-filtration: marked the ultra-filtration tubes as PR1 (presaturation protocol 1), PR2 (presaturation protocol 2) and rhADM, respectively, added 2 mL of 1 mg/mL and 10 μg/mL BSA solution into PR1 and PR2 respectively, and added 2 mL of rhADM immersion into rhADM tubes (rhADM1 and rhADM2). The tubes were then centrifuged at 1 500 × g for 20 minutes. The above steps were repeated for 3 times. Take the inner-tube of ultrafiltration into unused centrifuge tube. Added 4 mL of 10 μg/mL BSA solution in PR1 and PR2 tubes, 4 mL of rhADM immersion in rhADM tubes, centrifuged at 1 500 × g for 20 minutes, and then the filtration was colleted. Detecting BSA concentration: the BSA concentrations of all samples were detected by using the quantitative measure of residual BSA ELISA kit. The recoveries of 10 μg/ mL BSA solution treated by presaturation protocol 1 and 2 were calculated (untreated 10 μg/mL BSA solution was as the basic sample, marked R10 and R20 respectively). The correlation coefficient between the logarithm of the filtrate dilution and the absorbance (A) value was calculated and compared with that of water exact without ultra-filtration. Results The BSA concentration of PR1 and R10 was (23.80 ± 1.58) μg/ mL and (9.04 ± 0.24) μg/mL, respectively. The BSA concentration of PR2 and R20 was (8.64 ± 0.24) μg/mL and (8.12 ± 1.01) μg/ mL, respectively. The average recovery of 10 μg/mL BSA was 263.4% ± 16.9% and 106.5% ± 3.0% when the ultra-filtration tubes were presaturaed by PR1 and PR2 (P lt; 0.01), respectively. The BSA recovery of PR2 met the detecting demand. The correlations between A value and sample dilution were increased, the correlationcoefficient was raised from — 0.727 to — 0.960 after rhADM immersion were treated by ultra-filtration. Conclusion Theresults show that the matrix effects can be reduced effectively by ultra-filtration, indicating that an acceptable recovery of BSA can be acquired when ultra-filtration tube is presaturated by sample water extract.
Objective To explore the shortterm clinical effects of complex transplantation among the acellular dermal matrix(ADM) of heterogenic or heterocatal and autogenic split on the burnt wound as to find out a permanent substitution for the treatment on full skin thickness defect without scar. Methods Two kinds of ADM were used on the 18 patients with full thicknessburn wound through complex transplantation with autogenic splits. The patients with medialthickness autograft was used as control group. Survival rate was obtained 2 weeks after operation; contraction rate and the scores of Vancouver burn scale were obtained 8 weeks after operation. Results No significant difference was observed in survival rate among the three groups 2 weeks after operation(P＞0.05); no significant difference was observed in contraction rate of autografts and scores of Vancouver burn scale among the three groups 8 weeks after operation(P＞0.05). Conclusion ADM of heterogenic and ADM of heterocatal have similar effect on the reconstruction of skin, so the piglet ADM made in this way could be used as a substitution.