Objective To explore the expression of the vascular cell adhesion molecule 1 (VCAM1) in the acellular dermal matrix grafting in pigs. Methods Experimental models were established with 15 Inbred Strain mini pigs, 6 full-thichness skin defect wounds, 6 cm × 6 cm in size, were produced on both-side backs of the each pig, and then the pigs were randomly divided into 3 groups. In Group A (n=5, control) the thin auto-skintransplantation alone was made; in Group B (n=5), the grafting was performed in the acellular allo-dermal matrix combined with the thin auto-skins; in Group C (n=5), the grafting was performed in the acellular xeno-dermal matrixcombined with the thin auto-skins. The areas of the wounds were measured and the survival condition of the grafted skins was observed at 3, 9, 21 and 30 days after the grafting. The histological samples were harvested from the grafting area at 3, 6, 9, 12, 21 and 30 days after the procedure. The flow cytometry was employed to analyze the changes in the VCAM1 level in the sample at different time points after the grafting. Results In the 3 groups, the transplanted skin base was easily separated at 3 days after transplantation; the areas of the wound healing accounted for 94%±12%，92%±9%, and 91%±11%, respectively, at 21 days; good wound healing was achieved at 30 days. At 9 and 12 days after transplantation, there was an evidentlyincreased level of the VCAM-1 expression in the tissue samples in the composite skin grafting groups. Compared with the control group, the difference was significant (Plt;0.05); however, the VCAM-1 expression at 3 days was not statistically different between the composite skin grafting groups and the control group after transplantation. In contrast, the level of the VCAM-1 expression was significantly higher at 6 days in the control group than in the composite skin grafting groups (Plt;0.05). The levels of the VCAM-1 expression were significantly lower at 30 days than at 3 days after transplantation in all the 3 groups (plt;0.01). Conclusion The highest level of the VCAM-1 expression can be delayed in the composite skin grafting when compared with that in the thin auto-skins alone, which implies that the VCAM-1 expression may be correlated with angiogenesis and composite skin survival. The VCAM-1 expression is not different between the acellular allo-dermal matrix composite skin grafting groups and the acellular xeno-dermal matrix group.
Objective To compare the attachment and growth of fibroblasts on the different porcine accellular dermal matrix (ADM) so as to find the suitable scaffold for tissue engineering skin. Methods Fibroblasts (5×10 5) were seeded on 4 kinds of ADMs which were crosslinked with glutaraldehyde, uncrosslinked, crosslinked with glutaraldehyde and removed basement membrane, corsslinked with glutaraldehyde and then meshed. The same density fibroblasts were seeded on petri dish as a control. Cell count was done on the 1st, 3rd, 5th days after seeding. The at tachment of fibroblasts on ADM sw as observed by HE staining. Results The grow th and at tachment of fibroblasts on cro sslinked and non2meshed ADM increasedmarkedly w hen compared w ith the o thers. There w as no obvious difference betw een the group s of w ith o r w ithout basement membrane. Conclus ion The above results indicate that non2meshed and co rsslinked w ith glutaraldehyde ADM ismo re suitable fo r the at tachment and grow th of fibroblasts than the o thers and that the modified ADM can be used fo r the scaffo ld of t issue engineering skin.
【Abstract】 Objective To evaluate the long-term effectiveness of composite grafts of acellular dermal matrix (ADM)and autologous spl it-thickness skin in repairing deep burn wounds. Methods Between June 2002 and December 2008, 30 patients (42 wound) were treated. There were 25 males and 5 females, aged 3-52 years with a median age of 31 years. Of them, 24 burned patients had 35 wounds, including 23 deep second degree and 12 third degree wounds with a mean disease duration of 24 days (range, 3-45 days); 6 patients with hyperplastic scar had 7 wounds with a mean disease duration of 16 days (range, 9-21 days). The wound locations were neck (2 wound), hand (4 wounds), forearm and elbow (8 wounds), shoulder (3 wounds), poples (6 wounds), laps (4 wounds), ankle and legs (15 wounds), and the area of wounds ranged from 10 cm × 10 cm to 30 cm × 20 cm. After thorough debridement, tangential excision, and scar excision, ADM and autologous spl it-thickness skin graft were used to repair the wounds by one-step method. Results After operation, composite skin graft survived completely in 39 wounds of 27 patients, with a survival rate of 92.9%; partial necrosis occurred in 3 wounds of 3 patients (7.1%), and healed after dressing change and secondary skin graft. The patients were followed up 30-34 months (mean, 32 months) postoperatively. The appearance of the composite grafts were smooth and soft with good elasticity and low pigmentation. The activity and function of limbs recovered well. No scar hyperplasia was observed at the donor sites. Conclusion It can achieve good outcomes in appearance and function to use ADM and autologous spl it-thickness skin graft for repairing deep burn wounds in functional regions.
Objective To investigate the possible mechanism of the fibroblasts inducing the vascularization of dermal substitute. Methods Fibroblasts were seeded on the surface of acellular dermal matrix and cultivated in vitro to construct the living dermal substitute. The release of interleukin 8 (IL 8) and transfonming growth factor β 1(TGF β 1) in culture supernatants were assayed by enzyme linked immunosorbent assay, the mRNA expression of acid fibroblast growth factor (aFGF) and basic fibroblast growth factor (bFGF) were detected by RT-PCR. Then, the living substtute was sutured to fullth ickness excised wound on BALBouml;C m ice, and the fate of fibroblast w as observed by using in situ hybridizat ion. Results Fibroblasts cultured on acellular dermalmat rix p ro liferated and reached a single2layer confluence. Fibroblasts could secret IL 28 (192. 3±15. 9) pgouml;m l and TGF-B1 (1. 105±0. 051) pgouml;m l. There w as the mRNA exparession of aFGF and bFGF. Fibroblasts still survived and proliferated 3 weeks after graft ing. Conclusion Pept ides secreted by fibroblasts and its survival after graft ing may be relat ive to the vascularizat ion of the dermal subst itute.
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.
ObjectiveTo systematically review the efficacy of acellular dermal matrix (ADM) and subepithelial connective tissue flap (sCTG) on patients with gingival recession (GR).MethodsPubMed, EMbase, The Cochrane Library, CNKI, WanFang Data and VIP databases were electronically searched to collect randomized controlled trials (RCTs) about the efficacy of ADM and sCTG on patients with GR from inception to August 11st, 2019. Two reviewers indepeudently screened literature, extracted data and assessed the risk of bias of included studies, and then meta-analysis was performed by using RevMan 5.3 software and Stata 12.1 software.ResultsA total of 9 RCTs were included. The results of meta-analysis showed that: there were no significant differences in probing depth (PD) (MD3m=−0.04, 95%CI −0.18 to 0.11, P=0.63; MD6m=−0.01, 95%CI −0.13 to 0.12, P=0.90) and GR degree (MD3m=−0.10, 95%CI −0.37 to 0.18, P=0.48; MD6m=−0.02, 95%CI −0.33 to 0.29, P=0.89) in 3 and 6 months after operative between two groups. But the clinical attachment loss (CAL) in 3 months after operation (MD=0.33, 95%CI 0.00 to 0.66, P=0.05) and width of keratinized tissue (KTW) in 6 months after operation (MD=−0.48, 95%CI −0.76 to −0.20, P=0.000 7) of sCTG group were superior to ADM group, the differences were statistically significant.ConclusionCurrent evidence shows that there are no differences in PD and GR degree in 3 months and 6 months after operation between ADM and sCTG group. But the CAL in 3 months after operation and KTW in 6 months after operation of sCTG group is superior to ADM group. Due to limited quality and quantity of the included studies, more high-quality studies are needed to verify above conclusion.
ObjectiveTo understand the application of acellular dermal matrix (ADM) in implant-based breast reconstruction. MethodLiteratures on application of ADM in the implant-based breast reconstruction were reviewed. ResultsADM was widely used in the implant-based breast reconstruction and revisionary breast surgery. ADM could help to achieve a better reconstruction outcome by precisely locating the inferior mammary fold and strengthening the local control of the implant. However, whether ADM might increase the postoperative complications was controversial. ConclusionADM assisted implant-based breast reconstruction could achieve a better cosmetic outcome, but the large sample randomized controlled trial is needed to evaluate the application effect and risk of ADM.
ObjectiveTo compare the half-year clinical efficacy of three different surgical root coverage methods including lateral sliding flap (LSF), subepithelial connective tissue graft (CTG) and acellular dermal matrix allograft (ADM). MethodsEighteen patients (24 teeth) with gingival recession treated in our hospital between December 2012 and July 2015 were selected and divided into three groups according to a certain sequence with 8 teeth in each group. The three groups of teeth were treated with LSF, CTG and ADM respectively. Gingival recession, probing depth and keratinized gingival width at both baseline and 6 months after surgery of all patients were recorded for inner- and inter-group comparison. ResultsAll three methods proved to be effective within 6 months with an awerage of 2.8-4.0 mm in decrease extent of gingival recession (P<0.01). LSF did not significantly change the probing depth (P>0.05) as the other two did (P<0.01). The differences among three surgical methods compared before and after surgery were all significant (P<0.05). ConclusionLSF, CTG and ADM are all effective surgical means for root coverage. Within 6 months, CTG presents better effects than ADM, and ADM better than LSF.
ObjectiveTo study the preparation method of acellular dermal matrix (ADM) for cartilage tissue engineering and analyze its biocompatibility. MethodsThe dermal tissues of the calf back were harvested, and decelluarized with 0.5% SDS, and the ADM was reconstructed with 0.5% trypsin, cross-linked with formaldehyde, and modified with 0.5% chondroitin sulfate which can promote the proliferation of chondrocytes. And the porosity, cytotoxicity, and biocompatibility were determined. Co-cultured 2nd passage chondrocytes and bone marrow stromal cells in a proportion of 3 to 7 were used as seed cells. The cells were seeded on ADM (experimental group) for 48 hours to observe the cell adhesion. The expressions of mRNA and protein of collagen type Ⅱ were tested by RT-PCR and Western blot methods, respectively. And the expressions were compared between the cells seeded on the scaffold and cultured in monolayer (control group). ResultsAfter modification of 0.5% trypsin, the surface of ADM was smooth and had uniform pores; the porosity (85.4%±2.8%) was significantly higher than that without modification (72.8%±5.8%) (t=-4.384, P=0.005). The cell toxicity was grade 1, which accords to the requirements for cartilage tissue engineering scaffolds. With time passing, the number of inflammatory cells decreased after implanted in the back of the rats (P<0.05). The scanning electron microscope observation showed that lots of seed cells adhered to the scaffold, the cells were well stacked, displaying surface microvilli and secretion. The expressions of mRNA and protein of collagen type Ⅱ were not significantly different between experimental and control groups (t=1.265, P=0.235;t=0.935, P=0.372). ConclusionThe ADM prepared by acellular treatment, reconstruction, cross-linking, and modification shows perfect characters. And the seed cells maintain chondrogenic phenotype on the scaffold. So it is a proper choice for cartilage tissue engineering.
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.