SHH induces macrophage oxidative phosphorylation and efferocytosis to promote scar formation.

Excessive scar formation such as hypertrophic scars and keloids, resulting from trauma or surgical procedures, present a widespread concern for causing disfigurement, discomfort, and functional limitations. Macrophages play pivotal roles in maintaining tissue homeostasis, orchestrating tissue development, repair, and immune responses, and its transition of function and phenotype plays a critical role in regulating the balance between inflammation and tissue regeneration, which is central to cutaneous scar formation. Recent evidence suggests the involvement of Sonic Hedgehog (SHH) in the induction of anti-inflammatory M2-like macrophage phenotypes within tumor microenvironments. In our study, we observed increased SHH expression in human hypertrophic scars, prompting an investigation into its influence on macrophage polarization, efferocytosis, and cutaneous scar formation. Our findings reveal that SHH can enhance oxidative phosphorylation (OXPHOS) in macrophages, augment macrophage efferocytosis, and promote M2 polarization, finally contributing to the progression of cutaneous scar formation. Notably, targeting SHH signaling with vismodegib exhibited promising potential in mitigating scar formation by reversing the effects of enhanced OXPHOS and M2 polarization in macrophages. In conclusion, this study underscores the critical roles of macrophage metabolism, particularly OXPHOS, efferocytosis and SHH signaling in cutaneous scar formation. Understanding these mechanisms provides new avenues for potential interventions and scar prevention strategies.

Asymmetric adhesive SIS-based wound dressings for therapeutically targeting wound repair.

Severe tissue injuries pose a significant risk to human health. Conventional wound dressings fall short in achieving effective tissue regeneration, resulting in suboptimal postoperative healing outcomes. In this study, an asymmetric adhesive wound dressing (marked as SIS/PAA/LAP) was developed, originating from acrylate acid (AA) solution with laponite (LAP) nanoparticles polymerization and photo-crosslinked on the decellularized extracellular matrix small intestinal submucosa (SIS) patch. Extensive studies demonstrated that the SIS/PAA/LAP exhibited higher tissue adhesion strength (~ 33 kPa) and burst strength (~ 22 kPa) compared to conventional wound dressings like Tegaderm and tissue adhesive products. Importantly, it maintained favorable cell viability and demonstrated robust angiogenic capacity. In animal models of full-thickness skin injuries in rats and skin injuries in Bama miniature pigs, the SIS/PAA/LAP could be precisely applied to wound sites. By accelerating the formation of tissue vascularization, it displayed superior tissue repair outcomes. This asymmetrically adhesive SIS-based patch would hold promising applications in the field of wound dressings.

Application of Decellularized Adipose Matrix as a Bioscaffold in Different Tissue Engineering.

With the development of tissue engineering, the application of decellularized adipose matrix as scaffold material in tissue engineering has been intensively explored due to its wide source and excellent potential in tissue regeneration. Decellularized adipose matrix is a promising candidate for adipose tissue regeneration, while modification of decellularized adipose matrix scaffold can also allow it to transcend the limitations of adipose tissue source properties and applied to other tissue engineering fields, including cartilage and bone tissue engineering, neural tissue engineering, and skin tissue engineering. In this review, we summarized the development of the applications of decellularized adipose matrix in different tissue engineering and present future perspectives.Level of Evidence III This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A Meta-Analysis and Systematic Review of the Incidences of Complications Following Facial Thread-Lifting.

BACKGROUND: Facial thread-lifting (FTL) has gained more popularity, but the incidences of complications following FTL remain controversial. We aimed to perform a meta-analysis and systematic review to estimate the incidences of complications and to compare the short- and long-term satisfaction rates following FTL. METHODS: We searched PubMed, Web of Science, Embase and Cochrane library for eligible studies. The primary outcome was the incidences of complications following FTL. The secondary outcome was the satisfaction rate immediately and 6-month after FTL. The pooled incidences of complications and 95% confidence intervals were estimated using random-effects models. RESULTS: A total of 26 studies were included in this meta-analysis. Swelling was the most commonly reported complication with a pooled incidence of 35%, followed by skin dimpling (10%), paresthesia (6%), thread visibility/palpability (4%), infection (2%), and thread extrusion (2%). Absorbable threads were associated with a significantly lower risk of paresthesia (3.1% vs. 11.7%) and thread extrusion (1.6% vs. 7.6%) than non-absorbable threads. Patients older than 50 years had a significantly higher risk of dimpling (16% vs. 5.6%) and infection (5.9% vs. 0.7%) than their younger counterparts. In addition, the pooled long-term satisfaction rate was significantly decreased compared to it immediately after FTL (88% vs. 98%). CONCLUSION: Non-absorbable threads and older age of patients are associated with higher risks of complications. Therefore, we recommend a judicious use of non-absorbable threads and FLT in older patients. Furthermore, it should be discussed with patients preoperatively that the rejuvenation effect of FTL may not maintain in the long-term. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Stack-Up Technique to Create a Three-Dimensional Costal Cartilage Framework in Ear Reconstruction.

BACKGROUND: Ear reconstruction is one of the most challenging procedures for plastic surgeons. The costal cartilage is the most accepted material, and the framework fabrication methods also vary with the different ear reconstruction methods. This study aimed to present our clinical experience using a novel method for costal cartilage framework fabrication with the "fully expansion technique" ear reconstruction without a skin graft. From January 2017 to June 2018, 107 patients with unilateral microtia underwent ear reconstruction with the fully expansion technique. Costal cartilage was designed into different components and stacked up to form the multilayer structure and adequate projection. Preexpansion provided larger skin flap for fully cover the anterior and posterior parts of the framework. Then the anterior ear structures and the posterior sulcus, as well as the ideal bilateral symmetry, were established simultaneously without a skin graft. A total of 107 patients in this group were followed up for 8 to 24 month, and altogether 98 patients (91.6%) were satisfied with the reconstruction. The cartilage "stack-up" framework fabrication and fully expansion technique provided a well-defined, well-projected, and bilateral symmetrical reconstructed ear.

[Clinical application of the adjacent horn shaped perforator fasciocutaneous flap in the trunk area].

OBJECTIVE: To study the anatomy basis for the clinical application of the adjacent horn shaped perforator fasciocutaneous flap for the reconstruction of small and medium-sized defects in the trunk area. METHODS: (1) Ten adult antiseptic cadavers (20 sides) were perfused with red latex. The skin blood supply, line of the blood vessels, branches in accordance with the distribution and crossing were observed. (2) Fifteen cases with defects in the trunk were treated with the adjacent horn shaped perforator fasciocutaneous flaps. The defects size ranged from 5 cm x 5 cm to 13 cm x 13 cm with the size of the flaps ranging from 10 cm x 6 cm to 35 cm x 15 cm. RESULTS: The trunk skin is supplied by mainly 17 groups arteries such as thyrocervical trunk, internal thoracic artery, posterior intercostal arteries, superior epigastric artery, arteria epigastrica inferior, lumbar arteries, and so on. The perforators (diameter > 0.5 mm) numbers are about 20, 40, 24, 6, on the chest, abdomen and perineum, upper back, waist, respectively. All the flaps survived completely with primary healing both on donor and recipient sites. The flaps color, texture, function and appearance were satisfactory during the follow-up period of 1-24 months. CONCLUSIONS: The adjacent horn shaped perforator fasciocutaneous flap should be designed flexibly. The defects in the donor sites could be closed directly without skin graft. It is an effective, easy and ideal method for the reconstruction of large defects in the trunk.