Son D, et al. J Korean Med Sci. 2014 Jun;29(6):751-757. http://dx.doi.org/10.3346/jkms.2014.29.6.751

Background Among the various methods for correcting nasal deformity, the composite graft is suitable for the inner and outer reconstruction of the nose in a single stage. In this article, we present our technique for reconstructing the ala and columella using the auricular chondrocutaneous composite graft. Methods From 2004 to 2011, 15 cases of alar and 2 cases of columellar reconstruction employing the chondrocutaneous composite graft were studied, all followed up for 3 to 24 months (average, 13.5 months). All of the patients were reviewed retrospectively for the demographics, graft size, selection of the donor site and outcomes including morbidity and complications. Results The reasons for the deformity were burn scar (n=7), traumatic scar (n=4), smallpox scar (n=4), basal cell carcinoma defect (n=1), and scar contracture (n=1) from implant induced infection. In 5 cases of nostril stricture and 6 cases of alar defect and notching, composite grafts from the helix were used (8.9×12.5 mm). In 4 cases of retracted ala, grafts from the posterior surface of the concha were matched (5×15 mm). For the reconstruction of the columella, we harvested the graft from the posterior scapha (9×13.5 mm). Except one case with partial necrosis and delayed healing due to smoking, the grafts were successful in all of the cases and there was no deformity of the donor site. Conclusions An alar and columellar defect can be reconstructed successfully with a relatively large composite graft without donor site morbidity. The selection of the donor site should be individualized according to the 3-dimensional configuration of the defect.

The purpose of this study was to determine the late decline in viability of fat cells over time for fat tissue stored at −15°C and −70°C after harvest from abdominal liposuction. A total of 16 females were recruited for this study. The viability of fat cell specimens was measured after freezing for 1, 3, 7, 14, 28, and 56 days. A number of viable mature adipocytes were evaluated by fluorescence microscopy after staining with fluorescein diacetate and propidium iodide. The glycerol-3-phosphate dehydrogenase activity was measured in lipoaspirates before digestion and the XTT reduction assay was performed. In addition, the XTT reduction assay was also performed on isolated lipocytes and preadipocytes. The viability of mature adipocytes was very low for both the −15°C and −70°C samples after 1 day of freezing (13.3% ± 7.4% and 12.6% ± 6.3%, respectively). There was no statistically significant difference between the samples stored at the 2 temperatures. The GPDH activity of the lipoaspirates frozen, for 1 day, at −15°C and −70°C was 25.1% ± 10% and 28.7% ± 11%, respectively. For the XTT test, the fractional enzyme activity of the lipoaspirates frozen, for 1 day, at −15°C and −70°C was 30.0% ± 10.9% and 36.1% ± 12.3%, respectively. In addition, the adipocytes had low activity from day one: 15.4% ± 7.2% at −15°C and 11.5% ± 5.6% at −70°C. Furthermore, the preadipocytes had a low activity of 8.0% ± 6.0% at −15°C and 8.6% ± 3.8% at −70°C. At 8 weeks, there were few viable mature adipocytes and the activity of the cells was very low by XTT and GPDH testing. The results of this study showed that the viability of adipocytes declined rapidly after frozen storage for 1 day at both −15°C and −70°C, and decreased gradually in storage after 8 weeks; at which time only approximately 5% of the fat cells were alive. These findings suggest that the present fat preservation storage techniques using a −15°C freezer or a −70°C deep freezer are both inadequate to maintain the viability of fat cells.

The intrinsic factors associated with delayed wounds are ischaemia, infection, the presence of necrotic tissue and the presence of foreign bodies. This study was designed to create adaptable intrinsic factors induced delayed wound healing model in the pig, similar to clinical conditions. Four pigs were used in this study. Ten 4 × 4 cm fresh full‐thickness skin defect wounds were made on the back of each pig. Double‐flanged blocks made of silicon, a material that induces foreign body reactions, tissue ischaemia and causes local wound infection, were inserted into half of the wounds (n = 5) and removed at weeks 1, 2 or 3. The other wounds (n = 5) were left open for control purposes. Biopsies were obtained at weeks 1–4 for histological examinations and to evaluate inflammatory cytokines, which included tumour necrosis factor‐α (TNF‐α), interleukin (IL)‐1β and IL‐6. A Periscan PIM 3 Laser was used to measure degrees of ischaemia. A Visitrak Digital^® device was used to measure the sizes of unhealed wounds. After 3 weeks, unhealed mean wound sizes were 30·72 ± 3·36 and 2·91 ± 1·51 cm², in the experimental and control groups, respectively. Laser Doppler showed limited perfusion at wound margins in wounds containing silicone blocks. Histological findings corresponding to the severity of chronic inflammation were markedly higher and persisted until week 3 in the experimental group. The levels of IL‐1 and TNF‐α in the third week were statistically significantly higher in the model group. Also, in the fourth week, the level of TNF‐α in the model group was significantly higher. Epithelialisation was not complete at the end of the fourth week despite removing silicone blocks in the experimental group. On the basis of macroscopic and histological evaluations and molecular assessments, the described wound model has the characteristics of wound ischaemia and necrosis and persistent inflammation, which are very similar to delayed wounds of patients.

Background To minimize the inflammatory reaction and improve healing, a new modified dermal substitute composed of an atelocollagen, chondroitin-6-sulfate, and amniotic membrane (AM) was applied to full-thickness skin defects in a pig. Atelocollagen was extracted from bovine skin, and two modified dermal substitutes were generated according to the cross-linking type. Methods The AM-collagen dermal substitutes were characterized and compared with currently used dermal substitutes in a pig skin defect model. There were five experimental groups: dehydrothermal (DHT) cross-linking atelocollagen with the AM on the top (AM-DHT), DHT and chemical cross-linking atelocollagen with the AM on the top (AM-DHT/chemical), Terudermis, Integra, and AlloDerm. After 3×3 cm full-thickness skin defects on the back of a pig were created, each dermal substitutes dermal substitutes was randomly grafted on the defects. Two weeks after grafting, autologous partial-thickness skin was over-grafted on the neodermis. The take rate of the dermal substitutes, skin, and histological sections were all assessed at 1, 2, and 4 weeks postoperatively. Results More rapid healing and a higher take rate were evident in the AM-DHT and Terudermis groups. Histological examination revealed fewer inflammatory cells and more fibroblast hyperplasia in these two groups. Four weeks after surgery, the amount of newly formed collagen was significantly more appropriate in the AM-DHT group. Conclusions These observations provide supporting evidence that a newly developed amniotic-collagen dermal substitute may inhibit inflammatory reactions and promote wound healing.