Investigating the Adipogenic Effects of Different Tissue-Derived Decellularized Matrices.

Objective: Decellularized adipose-derived matrix (DAM) can promote adipogenic differentiation and adipose tissue remodeling, but the biological impact of tissue origin on DAM remains unknown. The present study aimed to investigate the effects of tissue origins on the adipogenic capacity of the decellularized matrix by comparing the cellular and tissue responses of DAM versus acellular dermal matrix (ADM). Methods: The in vitro response of adipose-derived stem/stromal cells (ADSCs) to DAM and ADM was characterized by proliferation and differentiation. The in vivo remodeling response was evaluated in the subcutaneous injection model of immunocompromised mice, using histology, protein expression, and transcriptome analysis. Results: Both DAM and ADM exhibited excellent decellularization effects and cytocompatibility. In the absence of exogenous stimuli, DAM could induce adipogenic differentiation of ADSCs compared with ADM. In the animal model, the levels of PDGF, VEGF, and ACRP30 were higher in the DAM groups than in the ADM group, and more neovascularization and extensive adipose tissue remodeling were observed. The mRNA-seq analysis indicated that the DAM implant regulated tissue remodeling by modulating Lat1/2 expression along with Hippo Signaling pathway in the early stage. Conclusion: Tissue origin can influence the biological response of the decellularized matrix. DAM can retain favorable tissue-specific characteristics after the decellularization process and have unique adipogenic effects in vitro and vivo, which can be fully utilized for soft tissue repair and regeneration.

Reconstruction of the Defect at Temporal Hairline by a Scalp Keystone Island Flap: Clinical Experience on 14 Cases.

BACKGROUND: The reconstructions of defects at the temporal hairline always require more complicated designs and higher surgical skills to acquire better aesthetic results. By taking advantage of the unique anatomy of the temporal region, the authors designed a scalp keystone island flap pedicled by superficial temporal fascia to repair defects on the temporal hairline. METHODS: The authors retrospectively analyzed the clinical data of 14 patients who had lesions adjacent to the temporal hairline between April 2018 and June 2020. Patients were diagnosed with basal cell carcinoma, squamous-cell carcinoma, or seborrheic keratosis. These lesions were resected and reconstructed by scalp keystone island flaps. The defects ranged from 2.0 cm × 1.5 cm to 3.0 cm × 3.5 cm. RESULTS: All patients were satisfied with postoperative morphology and reported no recurrence at the 6 to 24 months follow-up. Flaps in two patients were partially necrosed but eventually healed by dressing changes. The rest had the first intention of healing. CONCLUSIONS: The scalp keystone island flap is a very useful method to repair small or medium defects at the temporal hairline. This flap can be flexibly designed and easily performed with a high survival rate and good aesthetic results. It provides another surgical option for complicated reconstruction.

The use of modified keystone flap in periarticular or large superficial tumor resection surgery.

BACKGROUND AND OBJECTIVES: The keystone design perforator island flap (KDPIF) is often used to cover defects in reliable blood supply and similar skin patterns, but its mobility is limited, especially when the wound is large or occurs around joints. Here, we describe a modified KDPIF, boat-shaped flap. We added a V shape along the lateral arc, forming a V-Y flap on KDPIF's outer arc shapes like a sail. This paper also describes a clinical study to evaluate this method. METHOD: From September 2014 to March 2017, 31 patients were operated on using the boat-shaped flap in our department and were followed up annually with clinical evaluation. The wound locations included joints (n = 11), trunk (n = 18), and face (n = 2). Fifteen defects were ≥5 × 5 cm2 . RESULTS: After 6 to 24 months of follow-up, 29 patients had first-intention healing and were satisfied with the morphology and function. Secondary healing was observed in two patients, and the wounds were closed after dressing treatment for 2 weeks. CONCLUSION: The boat-shaped flap enhances the mobility and achieves strong resistance to tension. The modified curvilinear shape prevents the joint activity from being restricted, with visually concealed scars. It is particularly applicable for repairing large wounds and defects around joints.

Anatomical study of the extraocular check ligament system.

AIM: To clarify the gross anatomy structure of the check ligament of the palpebra superior in relation to congenital blepharoptosis operation. METHOD: Seven fixed and three fresh cadavers of Chinese adults (between 53 and 76 years old; 5 males and 5 females) were used. Gross dissection was performed on fourteen eyes in seven cadavers. In three fixed cadavers, six bulbus oculi received histological sections for immunohistochemical tests. RESULT: Below the levator upon the superior rectus, the check ligament described by Lockwood is found. It extends bilaterally and attaches to the orbital wall behind the inner and lateral canthus tendon. Between the inferior obliquus and the inferior rectus, we also found a sheath structure similar to the check ligament extending bilaterally to the orbital wall. These two structures form an annular fascial system surrounding the eyeball. The medial half of the fascial sheath is tenacious, and the immunohistochemical test proves that smooth muscle cells are found in this part. CONCLUSION: We call this whole fascial sheath surrounding the circumocular muscle the Extraocular Check Ligament System (ECLS), and it plays a restricting and checking role in the movement of the eyeball. Surgeons should be aware of the ECLS when performing ptosis or other blepharal surgery.

Experimental study of ASCs combined with POC-PLA patch for the reconstruction of full-thickness chest wall defects.

To explore the repairing effect of combination of adipose stem cells (ASCs) and composite scaffolds on CWR, the electrospun Poly 1, 8-octanediol-co-citric acid (POC)-poly-L-lactide acid (PLA) composite scaffolds were prepared, followed by in vitro and in vivo biocompatibility evaluation of the scaffolds. Afterwards, ASCs were seeded on POC-PLA to construct the POC-PLA-ASCs scaffolds, and the POC-PLA, POC-PLA-ASCs, and traditional materials expanded polytetrafluoroethylene (ePTFE) were adopt for CWR in New Zealand white (NZW) rabbit models. As results, the POC-PLA-ASCs patches possessed good biocompatibility as the high proliferation ability of cells surrounding the patches. Rabbits in POC-PLA-ASCs groups showed better pulmonary function, less pleural adhesion, higher degradation rate and more neovascularization when compared with that in other two groups. The results of western blot indicated that POC-PLA-ASCs patches accelerated the expression of VEGF and Collagen I in rabbit models. From the above, our present study demonstrated that POC-PLA material was applied for CWR successfully, and ASCs seeded on the sheets could improve the pleural adhesions and promote the reparation of chest wall defects.