Perfusion-decellularization of human ear grafts enables ECM-based scaffolds for auricular vascularized composite tissue engineering

Introduction: Human ear reconstruction is recognized as the emblematic enterprise in tissue engineering. Up to now, it has failed to reach human applications requiring appropriate tissue complexity along with an accessible vascular tree. We hereby propose a new method to process human auricles in order to provide a poorly immunogenic, complex and vascularized ear graft scaffold. Methods: 12 human ears with their vascular pedicles were procured. Perfusion-decellularization was applied using a SDS/polar solvent protocol. Cell and antigen removal was examined by histology and DNA was quantified. Preservation of the extracellular matrix (ECM) was assessed by conventional and 3D-histology, proteins and cytokines quantifications. Biocompatibility was assessed by implantation in rats for up to 60 days. Adipose-derived stem cells seeding was conducted on scaffold samples and with human aortic endothelial cells whole graft seeding in a perfusion-bioreactor. Results: Histology confirmed cell and antigen clearance. DNA reduction was 97.3%. ECM structure and composition were preserved. Implanted scaffolds were tolerated in vivo, with acceptable inflammation, remodeling, and anti-donor antibody formation. Seeding experiments demonstrated cell engraftment and viability. Conclusions: Vascularized and complex auricular scaffolds can be obtained from human source to provide a platform for further functional auricular tissue engineered constructs, hence providing an ideal road to the vascularized composite tissue engineering approach

Mechanical strength improvement of a soda-lime-silica glass by thermal treatment under flowing gas

International audienceThe incidence of thermal treatments in air, N-2 or NH3, on the mechanical properties of a soda-lime silica glass is presented. The effects of the treatment time and temperature were studied. Ammonia treatments lead to the most important compositional changes near the surface: SIMS and XPS techniques revealed a significant depletion in alkali and alkaline earth cations and a limited incorporation of nitrogen. IR-reflexion spectroscopy provided evidence for compositional changes near the surface, from a typical soda-lime glass towards a silica glass composition. The affected surface layer is typically about 1 mum deep and leads to significant changes of the local mechanical properties. Nanoindentation measurements showed that hardness increases whereas Young's modulus decreases both by similar to10% in a 300 nm thick surface layer. A significant increase of the indentation fracture toughness (K-c) from 0.72 to 0.89 MPa.m(1/2) was also noticed. The different processes leading to the cationic migration and to the changes of the glass surface properties were discussed. (C) 2003 Elsevier Ltd. All rights reserved

Surface damage of soda-lime-silica glasses: indentation scratch behavior

International audienceContact mechanics problems are Of fundamental interest both to understand the process of surface damage and matter removal in brittle materials, and to develop a method to evaluate their scratch resistance. In order to get insight into these problems in the case of soda-lime-silica glasses, a classical indentation apparatus was used. and an original scratch experimental setup was designed, allowing for a monotonic loading (or unloading) of the indenter combined with a controlled sliding of the specimen beneath the indenter. The influences of the normal load, the moisture level and the glass composition have been studied, and clear relationships were established between the glass compositions and the indentation-scratching behavior. The indentation and scratching characteristics such as the critical-crack-initiation loads and the transition loads between the different scratch regimes were correlated and interpreted in the light of the brittleness index and structural considerations. (C) 2003 Elsevier Science B.V. All rights reserved

Outcomes and Reliability of Perforator Flaps in the Reconstruction of Hidradenitis Suppurativa Defects: A Systemic Review and Meta-Analysis

International audienceIntroduction: Hidradenitis suppurativa (HS) is a common and debilitating disease, in which the only effective treatment involves a wide excision of the affected skin. Secondary wound healing and skin grafting are two well-known options for managing these defects, but perforator flaps provide a new therapeutic alternative by ensuring reconstructions of large defects, reducing donor site morbidity, and enhancing functional recovery. The aim of this study was to achieve a systematic review of perforator flaps use in HS. Patients and Methods: PubMed and Cochrane databases were searched from 1989 to 2021. The PRISMA statement was used in the study selection process and the review was registered on PROSPERO. Furthermore, patient characteristics, operative technique, complications, and recurrences were searched. Results: Thirty-six articles were selected including 286 patients and 387 flaps. Axillary localization was mostly represented (83.2%). Direct donor site closure was achieved in 99.1% of cases. In total, 15.1% of the flaps presented at least one of the following complications: wound dehiscence (5.5%), partial necrosis (2.9%), hematoma or seroma (2.1%), infection (2.1%), venous congestion (1.8%), and nerve injury (0.3%). Two cases of total necrosis were recorded. Recurrence of the disease was observed in 2.7% of the defects. Conclusions: Pedicled perforator flaps are a reliable and reproducible technique in the reconstruction of HS defects. They are associated with a low recurrence rate while ensuring an effective reconstruction with reduced morbidity and faster recovery compared to the techniques classically used in this indication

Abdominoplasty and lower body lift surgery improves the quality of life after massive weight loss: a prospective multicenter study

International audienceBACKGROUND: This study was conducted to assess the impact of abdominoplasty and lower body lift surgery following massive weight loss on both the general quality of life and the sexual life of patients. METHODS: We performed a multicenter prospective study on the quality of life after massive weight loss using three scoring questionnaires: The Short Form 36 questionnaire, the Female Sexual Function Index questionnaire, and the Moorehead-Ardelt Quality of Life Questionnaire. Seventy-two patients who underwent lower body lift and 57 patients who underwent abdominoplasty in three centers with pre and post-operative evaluation were included. RESULTS: The mean age of the patients was 43.2 ± 13.2 years. All categories of the SF36 questionnaire were statistically significant at 6 months, and all categories except health change were significantly improved at 12 months post-operative. Overall, the Moorehead-Ardelt questionnaire showed a higher quality of life in general (1.78 ± 0.92 and 1.64 ± 1.03, at 6 and 12 months respectively) and in all domains (self-esteem, physical activity, social relationships, work performance, and sexual activity). Interestingly, global sexual activity improved at 6 months but not at 12 months. Some domains of sexual life improved at 6 months (desire, arousal, lubrication, satisfaction), but only the desire stayed improved at 12 months. CONCLUSION: Abdominoplasty and lower body lift improve the quality of life of patients after massive weight loss as well as the sexual quality of life. This should be an additional valid reason for promoting reconstructive surgery for massive weight loss patients