The Specifics of Neovascularization of Wound Defects in the Oral Mucosa during Its Regeneration under a Piezoelectric Polymer Membrane.

We studied restoration of microvessels in the oral mucosa wound defects under a polymer piezoelectric membrane (group 2) and without it (group 1). The control group included animals with intact mucosa. On day 3, the expression of the vascular endothelial growth factor (VEGF) increased in all experimental groups, while the expression of CD34 increased only in group 2, which attested to intensive neoangiogenesis. On day 7, we observed a decrease in VEGF expression and an increase in CD34 expression that was more pronounced in group 2, which reflected the beginning of blood vessels maturation. More rapid formation and maturation of blood vessels in group 2 was confirmed by electron microscopy: on day 7, endothelial cells with mature organelles and signs of active transcapillary exchange were seen. On day 12, the immature blood vessels still predominated in group 1, while in group 2, the expression of angiogenesis markers decreased though remained above the control, which created prerequisites for the complete restoration of wound area vascularization in group 2. In group 1, the expression of VEGF and CD34 was significantly below the control, which attested to the development of poorly vascularized scar tissue.

Corrigendum: Application of the distally based sural neurocutaneous flaps in the management of foot and ankle defects in patients with diabetic foot.

[This corrects the article DOI: 10.3389/fendo.2022.1009714.].

Application of the distally based sural neurocutaneous flaps in the management of foot and ankle defects in patients with diabetic foot.

Background: We report our experience on the use of a distally based sural flap for soft tissue reconstruction of foot and ankle defects in patients with diabetic foot. Methods: The actual study is a retrospective, open, non-controlled, and clinical study of 25 patients treated with diabetic foot on whom reconstruction with distally based sural neurocutaneous flaps was performed from May 2019 to December 2021. Results: The mean age was 64.9 years, and there were 15 male and 10 female patients. The mean follow-up was 9.8 months, which ranged from 6 to 12 months. The size of the flaps ranged from 6 × 5 to 15 × 9 cm2. Twenty-two of the 25 flaps survived intact with sufficient blood supply. Two cases had a small superficial necrosis, which was resolved after a change of daily dressing and was heeled eventually. In one case, partial necrosis was observed that was managed with minor revision and the use of split-thickness skin graft. Conclusions: The distally based sural flap is considered to be useful for reconstruction of foot and ankle defects in patients with diabetic foot.

Treatment options for soft tissue defects in severe foot trauma in children.

OBJECTIVE: Severe foot trauma in children is a therapeutic challenge, with presence of devitalised and soiled distal tissues. Several reconstruction and covering procedures can be applied, including artificial dermis (AD), negative pressure wound therapy (NPWT), fasciocutaneous flaps and free flaps. Here, we have developed and evaluated an algorithm for treating severe foot injuries with skin defects in children. METHOD: Paediatric cases of severe foot injury treated over a 16-year period were retrospectively reviewed. Characteristics of the injuries, surgical procedures, complications and the modified Kitaoka score (clinical and functional rating score of the ankle and foot) were recorded. RESULTS: A total of 18 children were included. The mean age at the time of injury was four years and 10 months (range: 1-11 years). The mean follow-up period was 6.2 years. Of the children, 13 presented with an amputation (12 partial foot amputations and one whole ankle and foot). The skin defect was combined with tendon exposure in nine cases, and/or bone and cartilage in seven cases, and heel damage in two cases. A flap was implemented in eight cases, of which one failed. NPWT was used in 13 patients (for an average of 21 days) and was combined with AD in six patients. The mean modified Kitaoka score was 68 (range: 55-80). Additional surgery during the follow-up period was required in seven patients (dorsal skin retraction, a thick flap, osteoma, trophic ulcer or ankle deviation). CONCLUSION: Our algorithm suggests different therapeutic strategies for skin coverage and healing, depending on the size of the lesion and the exposed structures, and seems to offer good results. These procedures should be combined with NPWT to optimise these results (improved healing, reduced infections, decreased skin defects and enhanced granulation tissue) and so should be used more frequently.

Chemical Regeneration of Wound Defects: Relevance to the Canine Palatal Mucosa and Cell Cycle Up-Regulation in Human Gingival Fibroblasts.

Background: Trichloroacetic acid (TCA) is an agent widely applied in dermatology for skin regeneration. To test whether TCA can offer an advantage for the regeneration of oral soft tissue defects, the cellular events following TCA application were explored in vitro and its influence on the oral soft tissue wound healing was evaluated in a canine palate model. Methods: The cytotoxicity and growth factor gene expression in human gingival fibroblasts were tested in vitro following the application of TCA at four concentrations (0.005%, 0.05%, 0.5% and 1%) with different time intervals (0, 3, 9 and 21 h). One concentration of TCA was selected to screen the genes differentially expressed using DNA microarray and the associated pathways were explored. TCA was injected in open wound defects of the palatal mucosa from beagle dogs (n = 3) to monitor their healing and regeneration up to day 16-post-administration. Results: While the 0.5-1% concentration induced the cytoxicity, a significantly higher expression of growth factor genes was observed after 3 and 9 h following the 0.5% TCA application in comparison to other groups. DNA microarray analysis in 0.5% TCA group showed 417 genes with a significant 1.5-fold differential expression, involving pathways of cell cycle, FoxO signaling, p53 signaling, ubiquitin mediated proteolysis and cAMP signaling. In vivo results showed a faster reepithelialization of TCA-treated wounds as compared to spontaneous healing. Conclusion: TCA promoted the healing and regeneration of oral soft tissue wound defects by up-regulating the cell cycle progression, cell growth, and cell viability, particularly at a concentration of 0.5%.

Progress in developing decellularized bioscaffolds for enhancing skin construction.

The skin is the largest organ in the human body, and skin defects are very common. Skin flap transplantation is the best treatment for serious wound defects, and donor site tissues are always sacrificed during this process. Decellularized biomaterials, derived mainly from various nonautologous organs and tissues, have promising applications in tissue engineering and repair of wound defects. To date, decellularized mesothelium, intestine, amniotic membrane, dermis, and skin flaps have been developed and applied for skin coverage in animal models and clinical practice. In this review, we discuss recent advances in decellularized biomaterials for skin substitutes and future perspectives. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1849-1859, 2019.

Chemical Regeneration of Wound Defects: Relevance to the Canine Palatal Mucosa and Cell Cycle Up-Regulation in Human Gingival Fibroblasts

BACKGROUND: Trichloroacetic acid (TCA) is an agent widely applied in dermatology for skin regeneration. To test whether TCA can offer an advantage for the regeneration of oral soft tissue defects, the cellular events following TCA application were explored in vitro and its influence on the oral soft tissue wound healing was evaluated in a canine palate model.METHODS: The cytotoxicity and growth factor gene expression in human gingival fibroblasts were tested in vitro following the application of TCA at four concentrations (0.005%, 0.05%, 0.5% and 1%) with different time intervals (0, 3, 9 and 21 h). One concentration of TCA was selected to screen the genes differentially expressed using DNA microarray and the associated pathways were explored. TCA was injected in open wound defects of the palatal mucosa from beagle dogs (n = 3) to monitor their healing and regeneration up to day 16-post-administration.RESULTS: While the 0.5–1% concentration induced the cytoxicity, a significantly higher expression of growth factor genes was observed after 3 and 9 h following the 0.5% TCA application in comparison to other groups. DNA microarray analysis in 0.5% TCA group showed 417 genes with a significant 1.5-fold differential expression, involving pathways of cell cycle, FoxO signaling, p53 signaling, ubiquitin mediated proteolysis and cAMP signaling. In vivo results showed a faster reepithelialization of TCA-treated wounds as compared to spontaneous healingCONCLUSION: TCA promoted the healing and regeneration of oral soft tissue wound defects by up-regulating the cell cycle progression, cell growth, and cell viability, particularly at a concentration of 0.5%.