Regional-Controlled Tissue Expanders Increase Skin Expansion and Thickness Compared to Standard Tissue Expanders in a Rat Model.

BACKGROUND: Skin and soft-tissue expansion are widely used. However, the existing methods cannot expand targeted areas on the top flap. Thus, the authors developed a new expander with a partially thickened top. The authors hypothesized that pressure differences would lead to higher growth near nonthickened regions and lower growth near thickened regions, allowing targeted expansion. METHODS: Eighteen male Sprague Dawley rats (8 weeks old) were used; 20-ml rectangular regional-controlled expanders ( n = 12) and ordinary expanders ( n = 6) were implanted. Flaps on regional-controlled expanders were divided into nonthickened and thickened regions and tattooed. Discontinuous inflation began 14 days postoperatively, 3 ml every 3 days, until the volume reached 50 ml. Tattooed skin area and thickness were measured. Immunofluorescence staining detected cell proliferation (proliferating cell nuclear antigen-positive) and vascular density (CD31 + ). Growth factors (transforming growth factor-ß, epidermal growth factor, vascular endothelial growth factor, and basic fibroblast growth factor) were assessed by enzyme-linked immunosorbent assay. RESULTS: The expanded skin area of regional-controlled expansion nonthickened regions (396.2 ± 41.4 mm 2 ) was 33.8 ± 10.0 percent larger than that of thickened regions (297.8 ± 38.9 mm 2 ). Thickened regions had a 28.9 ± 14.6 percent thicker dermal layer (942.4 ± 55.5 µm) than nonthickened regions (737.1 ± 64.5 µm). Nonthickened regions had 295.0 ± 145.0 percent more proliferating cell nuclear antigen-positive cells (92.4 ± 16.2/mm 2 ) than thickened regions (25.6 ± 7.4/mm 2 ). The vascular density was 133.0 ± 61.7 percent higher in thickened regions (24.8 ± 4.7/mm 2 ) than in nonthickened regions (11.1 ± 2.7/mm 2 ) (all above, p < 0.05). CONCLUSIONS: Regional-controlled expansion specifically expands only the targeted area, causing thicker skin flaps with abundant vessels for defect repair. Although this technique has great clinical potential, it should be further validated with large animals and humans. ( Plast. Reconstr. Surg. 150: 1273, 2022.). CLINICAL RELEVANCE STATEMENT: This study presents the newly developed regional-controlled expansion technique that realized the targeted expansion. It is suitable for repairing defects and would contribute to shortening the expansion process and reducing complication rates.

A Comparative Study of Three-Dimensional Simulation in Nonsurgical Rhinoplasty With Hyaluronic Acid Fillers.

BACKGROUND: The use of 3-dimensional computer imaging has grown steadily over the past decade, especially with cosmetic facial surgery. The technological advance has influenced how we counsel patients, perform procedures, and assess outcomes. The purpose of this study was to analyze the feasibility of quantifying simulated versus actual outcomes for nonsurgical rhinoplasty with hyaluronic acid. METHODS: A retrospective review of 3-dimensional images (LifeViz Inc, France) for rhinoplasty patients was performed. Randomized preoperative, simulated, and actual images were rated by a blinded panel of physicians (1 = poor, 5 = excellent). In addition, a quantitative assessment of nasofrontal angle and nasolabial angle was conducted where paired and 2-sample t tests were performed (P < 0.05 as significant). RESULTS: Twenty-five patients were included in this comparison study. Fifty-six percent of preoperative images were rated as poor (mean, 1.7). The simulation received a mean score of 3.4 (good in 60% of cases), and 80% of actual cases were rated good to excellent (mean, 3.7). Mean nasofrontal angle decreased from 147.1 ± 1.2° preinjection to 143.3 ± 1.6° posttreatment, a mean change of 3.8 ± 2.0°. The mean nasolabial angle decreased from 125.5 ± 1.6° pretreatment to 117.5 ± 1.5° posttreatment. Average volume of actual dosage was 1.74 ± 0.18 mL. CONCLUSION: Three-dimensional simulation for patients undergoing nonsurgical rhinoplasty is helpful for surgical planning and patient communications. It provides a mechanism for critical self-evaluation and helps set patients with realistic expectations about rhinoplasty.

Midline Volume Filler Injection for Facial Rejuvenation and Contouring in Asians.

BACKGROUND: Hyaluronic acid (HA) injection is popular in cosmetic surgery because of its minimal invasion and immediate recovery. However, few injection techniques are specifically designed for Asians, considering their aesthetic and structural differences from those of Caucasians. METHODS: The midline volume injection technique was performed on 37 Asian females and 3 males at sites including the forehead, glabella, nasal dorsum, nasal base and chin. The treatment focused on improving the facial profile projection. 3D image data were collected, and facial aesthetic angles were calculated. Volume changes in facial parts were analyzed before injection and during follow-up. Patient satisfaction was assessed using the visual analog scale (VAS). RESULTS: The average injected filler volume was 6.14 ± 2.82 ml. The treatment optimized the facial contour and produced instant facial rejuvenation. On 3D images, the average midline volume increased by 6.02 ± 2.23 ml. An average volume decrease of 3.92 ± 1.94 ml was observed in the cheeks and was positively related to the increased midline volume. The average nasolabial and nasal facial angles were increased from 100.00 ± 7.37° to 107.93 ± 9.01° and 28.78 ± 3.28° to 31.78 ± 2.97°, while the mentolabial angle was decreased from 146.55 ± 7.83° to 141.13 ± 6.23°. The mean VAS scores were 2.28 ± 1.27 immediately after injection and 2.56 ± 1.20 after 6 months. CONCLUSIONS: The midline volume injection technique of HA fillers is suitable for Asians. It greatly enhances the facial profile, as illustrated by volume changes in 3D images, leading to a more attractive facial appearance. LEVEL OF EVIDENCE V: 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.

Developing a Strontium-Releasing Graphene Oxide-/Collagen-Based Organic-Inorganic Nanobiocomposite for Large Bone Defect Regeneration via MAPK Signaling Pathway.

Significant efforts have been dedicated to fabricating favorable biomaterial-based bone substitutes for the repair of large bone defects. However, the development of bone biomaterials with suitable physiochemical and osteoinductive properties remains a challenge. Here, novel strontium-graphene oxide (Sr-GO) nanocomposites that allow long-term release of Sr ions are fabricated, which are used to reinforce collagen (Col) scaffolds through covalent cross-linking. The prepared Sr-GO-Col scaffold demonstrates significantly high water retention rates and excellent mechanical properties compared with unmodified Col scaffolds. The Sr-GO-modified Col scaffolds display a strong effect on adipose-derived stem cells by facilitating cell adhesion and osteogenic differentiation and by promoting the secretion of angiogenic factors to stimulate the in vitro tube formation of endothelial cells. Additionally, the secretion of angiogenic VEGF and osteogenic BMP-2 proteins is increased, which may be attributed to the synergistic effects of GO and Sr on the activation of the MAPK signaling pathway. The Sr-GO-Col constructs were then transplanted into rat critical-size calvarial bone defects, which showed the best bone regeneration and angiogenesis outcome at 12 weeks. Moreover, histological staining results show that the Sr-GO-Col group achieved complete defect bridging with the newly formed bone tissue and the residual Sr-GO nanoparticles are phagocytosed and degraded by multinucleated giant cells. These findings reveal that the incorporation of inorganic Sr-GO nanocomposites into biocompatible Col scaffolds is a viable strategy for fabricating favorable substitutes that enhance the regeneration of large bone defects.

[Advances on research of human exposure to triclosan].

Triclosan, a broad-spectrum antimicrobial agent, was reported to have been widely detected in various human biological samples such as urine, blood and human milk among foreign populations. In China, limited reports have been found on human exposure to triclosan, and the reported urinary triclosan concentrations were significantly lower than that of American populations. Besides, the potential influencing factors still remain unclear regarding human exposure to triclosan, but evidences suggest that those in middle age and with higher household income and higher social class tend to have higher urinary triclosan concentrations. Furthermore, triclosan exposure tend to differ by sex, geography, heredity, metabolism and life style.