Evaluation of the safety and healing potential of a fibroin-aloe gel film for the treatment of diabetic foot ulcers.

OBJECTIVE: This study aimed to develop a wound dressing prepared from the blending of silkworm fibroin and aloe gel extract for use in the treatment of diabetic foot ulcers (DFUs). METHODS: Fibroin extracted from silkworm cocoons and aloe gel extract were dissolved in deionised water. pH levels were then adjusted with lactic acid solution. A simple casting technique was used to obtain the fibroin-aloe gel film. The surface morphology, hardness, flexibility and infrared spectrum of the sterilised film were tested. Swelling ratio was measured from changes in weight. The cytocompatibility of the film to human dermal fibroblast was determined using XTT assay. Hard-to-heal DFUs (grade I Wagner score) were treated with the film for four weeks. The application site was assessed for allergic reactions and/or sensitisation. Wound size was measured using standardised digital photography. RESULTS: A total of five hard-to-heal DFUs were treated. The obtained film sterilised with ozonation showed a non-porous structure. The elongation at break and tensile strength of the wet film were 9.00±0.95% and 6.89±1.21N, respectively. Fourier-transform infrared spectroscopy data indicated the presence of amides I, II and III, of peptide linkage, which are the chemical characteristics of the fibroin. Functional groups relating to healing activity of the aloe gel extract were also found. The swelling ratio of the film immersed in water for 24 hours was 0.8±0.01. In three DFUs (40-50mm2 in size), a wound area reduction of 0.4-0.8mm2/day was observed and were healed in 2-3 weeks. The remaining two SFUs (500mm2 in size) showed a wound area reduction of 4mm2/day and were almost closed at four weeks. No allergic reaction or infection was observed in any of the wounds. CONCLUSION: The obtained film showed a non-porous structure, and its strength and flexibility were adequate for storage and handling. The film tended to increase the proliferation of fibroblasts. The wound dressing showed potential for accelerating the healing rate of DFUs.

Pilot Clinical Evaluation of PoreSkin: A Human Acellular Dermal Matrix in Burn Scars.

Background: An extensive full-thickness wound need a graft, sometime very large. However, donor sites are often limited. Dermal substitutes are among the tissue-engineered products applied to clinical use. PoreSkin, a human acellular dermal matrix (hADM) manufactured by the Faculty of Medicine, Chulalongkorn University, is the first human dermal substitute developed in Thailand. Objective: Assess the safety and ability in achieving durable and definitively cosmetic coverage using PoreSkin. Material and Method: Eleven hypertrophic burn scars were enrolled in the present study. After scar excision, PoreSkin was placed followed by delayed split-thickness skin graft, three weeks later. The primary outcomes were the engraftment rate of the Poreskin and the skin graft. The secondary outcomes included complications and the final cosmetic appearance. Results: The engraftment rate of PoreSkin was 97.7% at day 21. The engraftment rate of autologous sheet skin graft placed over PoreSkin was 91.8%. Regarding the quality of the scar, using the Vancouver scar scale, it shows a statistically significant improvement (p<0.05). No major complications or rejection were observed. Conclusion: The performance of PoreSkin as a human acellular dermal matrix (hADM) is comparable to other commercial dermal substitutes in term of engraftment rate, complications, and rejection.

Vigorous wound irrigation followed by subcuticular skin closure in children with perforated appendicitis.

BACKGROUND: Although various protocols for the treatment of children with perforated appendicitis have been established, no one has cited incisional wound irrigation in detail. MATERIAL AND METHOD: The records of 69 children undergoing appendectomy for perforated appendicitis between 2004 and 2006 were reviewed. Wound irrigation prior to skin closure using 1-2 liters of normal saline was routinely performed in every case. The treatment protocol includes preoperative and postoperative antibiotic, early appendectomy, copious intraabdominal swab, vigorous wound irrigation and subcuticular skin closure. Either peritoneal lavage or transperitoneal drainage is omitted. RESULTS: Mean patients' age was 8.7 years, 47.8% were girls and there was no death. Subcutaneous fat thickness averaged 1.3 cm. Mean duration of hospitalization was 5.8 days. Of 69 appendectomies, 47 had simple perforation and 22 developed complicated perforation. There were four post-op complications (5.8%). Two patients had very small seroma at the lateral margin of incision, which resolved without additional treatment. One boy developed adhesion obstruction and enterocutaneous fistula, postoperatively. The patient required reoperation and recovered uneventfully. Only one child had wound infection. CONCLUSION: Vigorous wound irrigation followed by subcuticular skin closure for perforated appendicitis yields an acceptable outcome with low rate of wound complications.