Impaired response of mature adipocytes of diabetic mice to hypoxia.

Adipose tissue contains various cells such as infiltrated monocytes/macrophages, endothelial cells, preadipocytes, and adipocytes. Adipocytes have an endocrine function by secreting adipokines such as interleukin (IL)-6, tumor necrosis factor (TNF)-α, leptin, and adiponectin. Dysregulation of adipokines in adipose tissues leads to a chronic low-grade inflammation which could result in atherosclerosis, hypertension, and type 2 diabetes. A sustained inflammatory state, which is characterized by prolonged persistence of macrophages and neutrophils, is found in diabetic wounds. In addition, subcutaneous adipocytes are enormously increased in amount clinically in type 2 diabetes. However, the function of subcutaneous adipocytes, which play an important role in injured tissue subjected to hypoxia, has not been well characterized in vitro due to the difficulty of maintaining mature adipocytes in culture using conventional methods because of their buoyancy. In this study, we established a novel in vitro culture method of mature adipocytes by enclosing them in a hyaluronan (HA) based hydrogel to study their role in response to stress such as hypoxia. BrdU labeling and Ki67 immunostaining experiments showed that hydrogel enclosed mature adipocytes proliferate in vitro. Both mRNA and protein expression analyses for hypoxia regulated genes, such as vascular endothelial growth factor (VEGF) and heme oxygenase 1 (HO1), showed that mature adipocytes of wild type mice respond to hypoxia. In contrast, mature adipocytes of diabetic db/db and TallyHo mice did not efficiently respond to hypoxia. Our studies suggest that mature adipocytes are functionally active cells, and their abnormal function to hypoxia can be one of underlining mechanisms in type 2 diabetes.

Tissue expander breast reconstruction using prehydrated human acellular dermis.

INTRODUCTION: Human acellular dermal matrices help facilitate immediate tissue expander-implant breast reconstruction by providing support to the inferolateral pole, improving control of implant position, and enhancing early volume expansion. Although several freeze-dried human acellular dermal products have demonstrated reasonable safety and efficacy in immediate tissue expander-implant breast reconstruction, no dedicated studies have evaluated clinical outcomes of prehydrated human acellular dermal matrix (PHADM) in breast reconstruction. METHODS: The outcomes of 121 consecutive tissue expander reconstructions performed by the senior author using PHADM were evaluated. RESULTS: Mean intraoperative tissue expander fill volume was 256.6 ± 133 mL, 60% of final expander volume. Patients required an average of 3.2 additional expansions prior to tissue expander-to-implant exchange. Mean follow-up period after reconstruction was 44 ± 26.5 weeks. Complications occurred in 20 (16.5%) breasts, including 9 (7.4%) soft-tissue infections, 8 (6.6%) partial mastectomy flap necroses, and 2 (1.7%) seromas. Eleven (9.1%) breasts ultimately required explantation. Patients receiving radiation demonstrated a strong trend toward greater complications (30.8% vs. 13.7%, P = 0.0749). CONCLUSIONS: The outcomes and complication rates of PHADM tissue expander breast reconstruction are comparable to those reported with freeze-dried human acellular dermis.

Reconstruction of the zygomatic arch using a mandibular adaption plate.

Zygomatic complex fractures are one of the most common facial fractures treated by maxillofacial surgeons. Because of the importance of the zygomatic complex in midfacial skeletal orientation, comminuted zygomatic arch fractures can lead to significant morbidity and deformity. Common repair modalities include closed reduction via a Gilles approach, open reduction and internal fixation with screws and/or plating systems, primary bone grafting, and/or biosynthetics. In patients with significant comminution and arch defects, who are poor candidates for bone grafting, reconstruction can be difficult. In this clinical report, we present 2 patients with comminuted zygomatic arch fractures and significant bony defects, who were reconstructed with mandibular adaption plates alone without primary bone grafting. Over a mean follow-up period of 12.5 months, both patients healed well without any complications and had acceptable cosmetic outcomes.

Injectable fillers for facial rejuvenation: a review.

Health care practices are moving toward a more preventative focus. In addition to leading healthier lives and seeking help to eradicate disease, patients are enlisting the help of plastic surgeons to reduce the visible signs of aging. Traditionally, facial rejuvenation focused on skin tightening through resection and resurfacing. In recent years, increasing emphasis has been placed on minimally invasive cosmetic improvement. Today, plastic surgeons combat the effects of aging with a variety of non-incisional methods such as soft-tissue augmentation with facial fillers. A multitude of soft-tissue fillers exist, each with their own chemical constituents, indications, and effectiveness. It is imperative that plastic surgeons understand these agents when treating patients with cosmetic complaints.