To compare the effects of two different cryoprotectants on human desmoglein 1 (Dsg 1), and to provide experimental basis for the optimization of cryoprotectant. Methods Five donated thin spl it-thickness skin grafts were used, and the experiment was conducted within 4 hours after skin grafts harvest. The skin grafts were divided into 3 groups: group A (n=2) in which skin grafts were immersed in 0.5 mol/L trehalose/DMSO; group B (n=2) in which skin grafts were immersed in DMSO/propanediol; group C (n=1) in which fresh skin graft received no further treatment. Groups A and Bwere stored in — 196℃ l iquid nitrogen for 7 and 21 days, respectively, and then underwent experiment. mmunohistochemistry staining observation was performed on each group, RT-PCR method was used to detect the expression of Dsg 1 in skin. Results The immunohistochemistry staining showed that the protein in groups A and B was stained brown-yellow and distributed evenly 7 days after cryopreservation; the expression signal of epidermal basal cell was similar to that of group C; absorbance (A) value of groups A, B and C was 0.285 ± 0.006, 0.284 ± 0.004 and 0.287 ± 0.008, respectively, suggesting there was no significant difference between groups A and B and group C (P gt; 0.05). At 21 days after cryopreservation, the expression of positive cells in group B decreased; no obvious decrease was observed in group A, A value of groups A and B was 0.282 ± 0.004 and 0.275 ± 0.005, respectively, indicating there was a significant difference between group B and groups A and C (P lt; 0.05). RT-PCR detection showed that A value of groups A and B at 7 days after cryopreservation was 0.810 ± 0.012 and 0.803 ± 0.008, respectively; A value of groups A and B at 21 days after cryopreservation was 0.806 ± 0.008 and 0.782 ± 0.013, respectively; and the A value of group C was 0.814 ± 0.012, indicating there was significant difference between group B and groups A and C at 21 days after ryopreservation (P lt; 0.05), and no significant differences among groups were noted at other time points (P gt; 0.05).Conclusion Trehalose/DMSO is better than traditional cryoprotectant DMSO/propanediol in protecting Dsg 1 of human skin.
To compare the effect of trehalose with that of different traditional cryoprotectants on human skin and to detect the new protection mechanism of trehalose in hypothermia. Methods The skins to be cryopreserved were first treated with DMSO/Propyleneglycol (D/P group), trehalose/DMSO (T/D group), DMSO/ serumfree keratinocyte medium(D/K group), DMEM (DMEM group), respectively, so as to be compared with fresh skin (control grouop). Then the histological structure of skin of different groups was observed and analyzed by pathological technology (SP immunohistochemistry, DAB staining). Furthermore, the influence of trehalose on α-actinin at gene level with RT-PCR was investigated. The viabil ity of skin in 5 respective groups was evaluated by using succinate dehydrogenase (SDH). The experiments were carried out 14 days after cryopreservation. Results The results of immunohistochemistry showed that A values of control group, T/D group, D/P group, D/K group and DMEM group were 27.50 ± 7.92, 18.40 ± 5.81, 13.10 ± 5.11, 11.50 ± 4.54 and 5.30 ± 2.14, respectively. There was no significant difference between control group and T/D group (P gt; 0.05), but control group was significantly different from the other groups (P lt; 0.05). The results of PCR studies showed that A values of control group, T/D group, D/P group, D/K group and DMEM group were 0.816 ± 0.134, 0.723 ± 0.245, 0.564 ± 0.265, 0.245 ± 0.071 and 0.148 ± 0.048, respectively. Control group was not significantly different from T/D group and D/P group (P gt; 0.05), but was significantly different from D/K group and DMEM group (P lt; 0.05). The results of SDH showed that A valuse of control group, T/D group, D/P group, D/K group and DMEM group were 18.2 ± 3.7, 12.3 ± 3.6, 10.2 ± 2.4, 7.3 ± 2.1 and 5.7 ± 1.5, respectively. There was no significant difference between control group and T/D group (P gt; 0.05), while control group was significantly different from the other groups (P lt; 0.05). Conclusion The results suggest that cryopreservation protocol-trehalose/DMSO is better than the traditional cryoprotectant for ryopreservation on α-actinin of human skin.
Objective To investigate the effectiveness of repairing severe cicatricial contracture deformity in the web-space by kite-like incision combined with full-thickness skin grafting. Methods Between June 2008 and September 2011, 31 patients (87 web-spaces) with severe cicatricial contracture deformities in the web-spaces were treated. There were 24 males and 7 females, aged 5-43 years (median, 22 years). The causes of injuries were flame burn (26 cases), scald (3 cases), electric arc burn (1 case), and chemical burn (1 case). The degree of burn was deep second degree (14 cases) and third degree (17 cases). The interval time from injury to operation was 10 months to 17 years (median, 2.2 years). The kite-like incision was marked on the scar in the web-space. The rhombic scar between the adjacent metacarpophalangeal joints was excised, and cicatricial contracture was released completely. The secondary wound in the web-space was repaired with full-thickness autogeneic skin grafting. The secondary wound at donor site was directly sutured. Results All full-thickness skin grafts survived well. The incisions at donor sites healed primarily. Of 31 patients, 29 (82 web-spaces) were followed up 6-18 months (mean, 13 months). The sizes and depths of reconstructed web-spaces were similar to those of normal ones. No secondary cicatricial contracture was observed, and the function of fingers recovered well. Conclusion The short-term effectiveness is satisfactory by kite-like incision combined with full-thickness skin grafting for repairing severe cicatricial contracture deformities in the web-space, while the long-term effectiveness needs further observation.
Objective To investigate the feasibility of repairing secondary wounds after scar excision in patients with scar contracture in whole dorsum of the hands by expanded full-thickness skin grafts. Methods Between February 2008 and February 2011, 15 patients (19 hands) with scar contracture in whole dorsum of the hands were treated. There were 12 males (14 hands) and 3 females (5 hands), aged 18-43 years (mean, 28.6 years). The disease duration was 6-22 months (mean, 13.2 months). All cases complicated by different degrees of metacarpophalangeal joint extension deformity and interphalangeal joint flexion deformity. In one-stage operation, soft tissue expanders were implanted at donor sites, and the time of water injection was 4-5 months; in two-stage operation, scar was excised and secondary wound (14 cm × 9 cm-25 cm × 16 cm in size) was repaired with the expanded full-thickness skin grafts. Results After one-stage operation, the others had good blood supply except 1 case of skin necrosis in the center of expanded skin flap. After two-stage operation, the full-thickness skin grafts survived well in 18 hands; subepidermal effusion occurred in 1 hand, which was cured after changing dressing. The incisions at donor sites healed well in all cases. All patients were followed up 6-18 months (mean, 13.7 months). The grafts were excellent in color, texture, and elasticity, and no hypertrophic scar was observed at the edge and joint of the grafts. The hand function recovered well; the flexion and extension of wrist joint, metacarpophalangeal joint and interphalangeal joint were normal. Conclusion The expanded full-thickness skin graft is a suitable solution to repair effectively scar contracture in whole dorsum of the hands because it has good results in the cosmetic appearance and function recovery of the hands.
Objective To evaluate the cl inical effect and the pathological characteristics of acellular allogeneic dermal matrix in repairing unstable burn scar. Methods From January 2007 to June 2008, 19 cases of unstable burn scars (24 parts) were treated, including 16 males (20 parts) and 3 females (4 parts) with a median age of 27 years (range, 3-58 years). Theinjury was caused by flame (14 cases, 18 parts), electricity (4 cases, 5 parts), and hot water (1 case, 1 part). The unstable burn scars located on hands (8 cases), forearms (2 cases), thighs (3 cases), legs (2 cases), feet (2 cases), chest (1 case), and abdomen (1 case). Scar formed for 3 months to 1 year. The area of defect varied from 7 cm × 5 cm to 22 cm × 15 cm after scar removal. Defects were covered with acellular allogeneic dermal matrix and autogenous spl it-thickness skin graft. At 6-18 months after operation, the pathological observations of the epidermis, the basal membrane, and structural components of the dermis were done. Results All wounds healed by first intention. Scar ulcer disappeared completely in 18 cases and the composite skin grafts all survived. Some bl isters occurred in 1 case and were cured after dressing changing. All patients were followed up 10 months to 2 years (18 months on average). The grafted-skin was excellent in the appearance, texture, and elasticity. The function recovered well. Only superficial scar was observed at skin donor sites. Pathological observation showed that the epidermis and the basal membrane of the skin grafts were similar to that of normal skin, and no significant difference was found in newly capillaries between them. Collagen fibers arranged regularly, and there were few inflammatory cells in the matrix. Conclusion Acellular allogeneic dermal matrix with autogenous spl it-thickness skin graft may effectivly repair the wound after removing the unstable burn scar, and its structure is similar to that of normal skin.