Hyaluronic acid/chitin thermosensitive hydrogel loaded with TGF-ß1 promotes meniscus repair in rabbit meniscus full-thickness tear model.

Repair of the damaged meniscus is a scientific challenge owing to the poor self-healing potential of the white area of the meniscus. Tissue engineering provides a new method for the repair of meniscus injuries. In this study, we explored the superiority of 2% hyaluronic acid chitin hydrogel in temperature sensitivity, in vitro degradation, biocompatibility, cell adhesion, and other biological characteristics, and investigated the advantages of hyaluronic acid (HA) and Transforming Growth Factor ß1 (TGF-ß1) in promoting cell proliferation and a matrix formation phenotype. The hydrogel loaded with HA and TGF-ß1 promoted cell proliferation. The HA + TGF-ß1 mixed group showed the highest glycosaminoglycan (GAG) content and promoted cell migration. Hydroxypropyl chitin (HPCH), HA, and TGF-ß1 were combined to form a composite hydrogel with a concentration of 2% after physical cross-linking, and this was injected into a rabbit model of a meniscus full-thickness tear. After 12 weeks of implantation, the TGF-ß1 + HA/HPCH composite hydrogel was significantly better than HPCH, HA/HPCH, TGF-ß1 + HPCH, and the control group in promoting meniscus repair. In addition, the new meniscus tissue of the TGF-ß1 + HA/HPCH composite hydrogel had a tissue structure and biochemical content similar to that of the normal meniscus tissue.

Effectiveness of Core Excision Technique for Keloids: A Systematic Review.

BACKGROUND: The keloid core excision technique mitigates the risk of wound tension and promotes favorable morphological outcomes. However, whether residual keloid tissue or other factors increase the risk of recurrence remains unclear. This systematic review aimed to evaluate the therapeutic outcomes of core excision techniques for keloids. METHODS: A systematic literature review was conducted by searching PubMed, Embase, Web of Science Core Collection, and Cochrane Library databases on July 30, 2023. The search terms employed were "keloid," "core excision," "intralesional excision," "intramarginal excision," "rind flap," and "fillet flap." The inclusion criteria for the studies were established in advance and evaluated by multiple investigators. RESULTS: Overall, 20 studies involving 926 keloid cases managed through core excision were included. Adjuvant therapies were used in 19 studies, with radiotherapies and steroid injections emerging as the predominant methods. The recurrence rates ranged from 0% to 28.6%. Residual scar tissue after core excision and complications, such as flap necrosis and hematoma, are the major factors contributing to recurrence. CONCLUSION: The core excision technique is a surgical treatment of keloids with a low recurrence rate when combined with adjuvant therapies. However, randomized controlled trials and conclusive quantitative studies are necessary to further investigate the effects of the core excision technique on keloids.

Angiosome-Guided Perfusion Decellularization of Fasciocutaneous Flaps.

BACKGROUND: Tissue engineering based on whole-organ perfusion decellularization has successfully generated small-animal organs, including the heart and limbs. Herein, we aimed to use angiosome-guided perfusion decellularization to develop an acellular fasciocutaneous flap matrix with an intact vascular network. METHODS: Abdominal flaps of rats were harvested, and the vascular pedicle (iliac artery and vein) was dissected and injected with methylene blue to identify the angiosome region and determine the flap dimension for harvesting. To decellularize flaps, the iliac artery was perfused sequentially with 1% sodium dodecyl sulfate (SDS), deionized water, and 1% Triton-X100. Gross morphology, histology, and DNA quantity of flaps were then obtained. Flaps were also subjected to glycosaminoglycan (GAG) and hydroxyproline content assays and computed tomography angiography. RESULTS: Histological assessment indicated that cellular content was completely removed in all flap layers following a 10-hour perfusion in SDS. DNA quantification confirmed 81% DNA removal. Based on biochemical assays, decellularized flaps had hydroxyproline content comparable with that of native flaps, although significantly fewer GAGs (p = 0.0019). Histology and computed tomography angiography illustrated the integrity and perfusability of the vascular system. CONCLUSION: The proposed angiosome-guided perfusion decellularization protocol could effectively remove cellular content from rat fasciocutaneous flaps and preserve the integrity of innate vascular networks.

Concentrated Deoiled Fat: A Novel Method of Fat Processing to Improve Fat Graft Survival-A Basic Research.

BACKGROUND: Oil compromises graft outcomes via inflammation, which accounts for the unpredictability of volume retention rates as low as 20%. Existing techniques for oil removal are relatively inefficient. In this study, a novel approach was taken to prepare concentrated deoiled fat (CDF) by utilizing flocculation and centrifugation to remove the oil. The hypothesis put forward in this study was that CDF would exhibit improved volume retention and quality by enhancing purification efficiency and reducing inflammation. METHODS: This basic research involved both in vitro and in vivo experiments using samples obtained from women who underwent abdominal liposuction. The CDF was prepared by flocculation and centrifugation. In the vitro experiments, the microstructure of fat was assessed using Calcein acetoxymethyl ester (AM) staining for living cells and propidium iodide (PI) staining for dead nuclei in two groups: Coleman fat group and CDF group. Additionally, the glucose uptake capacity of these two groups was evaluated using the glucose transport test (GTT). In the vivo experiments, the study included three groups: two experimental groups (low-volume concentrated deoiled fat, LCDF; high-volume concentrated deoiled fat, HCDF) and one control group (Coleman fat), with 10 healthy female BALB/c nude mice in each group, 1ml of the graft was injected subcutaneously to each mouse. After 8 weeks, the fat grafts were harvested and subjected to volume evaluation, HE staining and immunostaining for perilipin to assess graft outcomes. RESULTS: In the vitro experiments, the concentration rate of the CDF was found to be 79.6% that of Coleman fat, with 15.1% more oil separated. Cell viability, as assessed by AM/PI staining, did not show a significant difference between the two grafts, but the results of the GTT showed that the tissue viability of the CDF was higher than that of Coleman fat. In the vivo experiments, the CDF had higher volume retention than Coleman fat, as measured by water displacement. Histopathologic scoring indicated that HCDF group and LCDF group had a more intact fat structure with fewer vacuoles, inflammation, and fibrosis compared to Coleman fat. Additionally, the percentages of perilipin-positive area in the LCDF group and HCDF group were higher than in the Coleman group, indicating improved graft quality and outcome with the use of concentrated deoiled fat. CONCLUSIONS: "Concentrated deoiled fat" refers to an autologous fat graft from which oil has been removed by flocculation and centrifugation. This process increases volume retention and viable cells and decreases infiltrated inflammatory cells. 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 .

Pre-expanded Brachial Artery Perforator Propeller Flap: An Addition to the Armamentarium for Postburn Axillary Contracture Reconstruction.

BACKGROUND: Postburn axillary contracture is a common complication that leads to functional impairment and unsatisfactory aesthetic outcomes. This article aims to present our experience with axillary contracture reconstruction using pre-expanded brachial artery perforator propeller (BAPP) flaps and provide a systematic review of other regional or free flaps. METHODS: This retrospective study included patients who underwent postburn axillary contracture reconstruction using pre-expanded BAPP flaps from 2015 to 2022. Data on the flap characteristics and function of the affected shoulders were recorded. A systematic review was conducted by retrieving studies that assessed the outcomes of regional or free cutaneous/fasciocutaneous flaps for treating axillary contracture from PubMed, Web of Science, EMBASE, and Scopus published before October 1, 2023. RESULTS: Twelve pre-expanded BAPP flaps measuring up to 26 cm × 11 cm (mean, 116.9 cm 2) survived completely with no major complications, and the donor sites were closed primarily. The average range of shoulder abduction increased from 77.9° to 141.7° (p=0.002). The systematic review included 34 articles, reporting 12 regional and three free flaps. The most reported flaps were the thoracodorsal artery perforator flap, scapular flap, and parascapular flap. The overall complication rate ranged from 0 to 25%, and the average change in shoulder abduction ranged from 72.5° to 99.4°. CONCLUSIONS: Pre-expanded BAPP flaps can be effectively used for reconstructing postburn anterior axillary fold contracture. The donor site availability and the specific axillary contracture type should be considered when selecting a regional or free flap.

Finding Perforator "Freeway" for Design Optimization of Expanded Flaps by Indocyanine Green Angiography.

SUMMARY: Indocyanine green angiography (ICGA) is a useful tool for the visual assessment of superficial blood flow. Herein, we used ICGA to visualize perforator branches and linking vessels to provide a road map for flap design of an expanded flap. Twenty-eight expansions were planned to use back-cut technique in 26 patients. ICGA was used to visualize perforator branching pattern with the linking vessels and the venous network in the expanded flap before expander explantation. The appropriate perforator was selected, and the flap was designed following the axiality of its branch linked by true anastomoses. The vein running closely was chosen as the axial vein. The back cut was designed to avoid transection of the axial artery and vein. Patient demographics, defect characteristics, and reconstructive outcomes were assessed. ICGA clearly visualized the perforator branches and the linking vessels in the expanded flap at the head and neck, trunk, and extremity. The back-cut flap containing the axial artery and vein was raised successfully in 27 expansions. The arterial perforator and superficial vein separated greatly and resulted in design modification from back-cut to advancement flap in one expansion. All expanded flaps met the reconstructive needs and exhibited complete survival. ICGA allowed the visualization of the preoperative topography of the vascular network in the expanded flap and helped surgeons locate the vascular axis and perform an appropriate back-cut design for efficient and safe flap transfer.

A New Option to Preserve Esthetics in Perioral Defect Reconstruction With Normal Anatomical Structures: Bipedicled Preexpanded Forehead Flap With Random Skin Flap Extension.

Plastic surgeons charged with reconstructing extensive perioral defects face dual challenges of functional restoration and esthetic considerations. While forehead flaps are commonly used to reconstruct perioral defects, in cases involving partial upper lip defects where normal anatomical structures are preserved, traditional forehead flaps may compromise esthetics. This study aimed to address this issue by employing bipedicled preexpanded forehead flaps based on the frontal branches of the superficial temporal artery (hereafter, "STA-bfb-based preexpanded forehead flap") with random flap extensions to repair perioral defects. Between April 2004 and July 2020, 7 patients (5 males and 2 females; 6 had post-burn facial scars involving the entire lower lip and part of the upper lip, and 1 presented with noma sequelae) underwent perioral defect reconstruction using this approach. Tissue expanders were placed in the forehead donor area, and an STA-bfb-based preexpanded forehead flap with random flap extensions was used to repair the perioral defect. The flap pedicle was divided into 3 weeks. All flaps remained viable with no perfusion-related complications. At follow-up 12 to 96 months later, the color and texture of the flaps demonstrated excellent compatibility with the surrounding skin, suggesting that the use of an STA-bfb-based preexpanded forehead flap with random skin flap extensions is a reliable method for repairing perioral defects. The authors' results have implications for plastic surgeons seeking a solution for challenging perioral defect reconstructions, balancing the need for esthetic outcomes with functional restoration.

Recovery of subcutaneous orbital fascia under preserved skin below the original crease in the repair of excessively high double-eyelid folds.

BACKGROUND: High-eyelid fold is a common complication of upper eyelid surgery. This study proposed a novel technique for correcting high-eyelid fold in Asian patients with little eyelid skin and thick orbital fascia to improve cosmetic outcomes and patient satisfaction. METHODS: We retrospectively analysed the clinical data of 38 patients with high-eyelid fold repaired at the Plastic Surgery Hospital, Chinese Academy of Medical Sciences, from July 2017 to April 2022. All patients were treated using this method of preserving the high-eyelid fold and reconstructing the subcutaneous orbital fascia. Postoperative outcomes were reviewed and analysed using objective measures and subjective surgeon and patient evaluations. RESULTS: Thirty-eight patients (71 eyes) were included. Postoperative follow-up was for 6-25 months. At 6 months postoperatively, the mean anatomic crease height decreased from 10.45 mm to 6.22 mm, mean pretarsal show decreased from 3.20 mm to 1.61 mm, and mean margin reflex distance in 1 of the 31 patients with ptosis increased from 2.93 mm to 3.87 mm (P < 0.001). The compliance rate between the surgeon's assessment and patient satisfaction was 89.5%, with 31 cases considered good by both the surgeon and patient and one case considered poor by both (undercorrected ptosis), though a satisfactory result was achieved after reoperation. Neither recurrence of the original crease nor serious complications were reported. CONCLUSION: By preserving high-eyelid folds and reconstructing the subcutaneous orbital fascia, unnaturally high- and deep-eyelid folds were converted to lower, nondepressed folds.

Extensive Defect Reconstruction Using Multiple Perforator Propeller Flaps in a Jigsaw Puzzle Approach.

BACKGROUND: Reconstruction of extensive defects remains challenging for plastic surgeons. We report our experience with extensive defect reconstruction using multiple perforator propeller flaps and provide a systematic review of the literature on this approach. METHODS: This retrospective study included patients who underwent defect reconstruction with multiple perforator propeller flaps from 2014 to 2021. A systematic review was conducted by retrieving studies on reconstructive strategy from PubMed, Web of Science, EMBASE, and Scopus published before December 1, 2022. RESULTS: Thirty patients underwent defect reconstruction using 65 perforator propeller flaps. The posterior trunk (66.7%) was the most common site of defects. Complete flap survival was achieved in 61 flaps (93.8%). Partial necrosis of four flaps in three patients and venous congestion of one flap resulted in an overall complication rate of 13.3%. One flap experienced distal tip necrosis in 21 patients undergoing posterior trunk or perineal defect reconstruction, leading to an overall complication rate of 4.7%. Other complications were observed during the reconstruction of defects in the lower extremities (one of five patients) and anterior trunk (two of four patients). In the systematic review, 11 articles involving 74 patients were identified. The commonly reported locations of the defects were the perineum (55.4%) and posterior trunk (33.8%). Flap-related complications included venous congestion, and no flaps were lost. CONCLUSIONS: This study on the use of multiple perforator propeller flaps in a jigsaw puzzle approach demonstrated that the method can be effectively used for extensive posterior trunk and perineal defect reconstruction.

[Principle and clinical application of keloid core excision technique].

Objective: To review the research progress of the principle and clinical application of keloid core excision technique. Methods: The literature on keloid core excision technique at home and abroad in recent years was extensively reviewed, and the principle, development history, indications, advantages and disadvantages of this technique were summarized, and the existing controversies were analyzed. Results: Keloid core excision is a technique to remove the inner fibrous core from the keloid and cover the defect with the keloidal flap. It reduces the wound tension, yields good aesthetic results in the treatment of ear keloids, and reduces the recurrence rate of keloids combining with adjuvant therapies. Conclusion: The keloid core excision technique has specific advantages, yet its overall efficacy remains controversial. Further studies are imperative to explore the mechanisms regarding keloid recurrence and the vascular supply principles of the keloidal flap. It is also necessary to define appropriate surgical indications and safety protocols of this technique.

[Application of indocyanine green angiography in repair of facial soft tissue defect using superficial temporal artery based forehead flap].

Objective: To explore the feasibility of using indocyanine green angiography in mapping the superficial temporal vessels and assisting design and harvesting of the superficial temporal artery based forehead flap. Methods: A clinical data of 14 patients with facial soft tissue defects repaired with superficial temporal artery based forehead flaps between October 2015 and November 2022 was retrospectively analyzed. There were 9 males and 5 females with a median age of 9.5 years (range, 3-38 years). The forehead flaps were used to reconstruct facial soft tissue defects following excision of facial scar (8 cases) or congenital melanocyte nevus (6 cases). The size of defects ranged from 3 cm×2 cm to 24 cm×9 cm. Before operation, the indocyanine green angiography was used to map the superficial temporal artery and vein, and to analyze the relationship of the arteries and veins. The forehead flaps with unilateral superficial temporal fascia as the pedicle was transferred to repair the small facial defect in 2 cases. The facial pedicle contained the frontal branch of the superficial temporal artery and 2 cm of the superficial temporal fascia around the vessel, and the tiny accompanying vein of the frontal branch of the superficial temporal artery was used as the outflow of the flap. The forehead flaps with the skin pedicle including bilateral or unilateral superficial temporal fascia and the overlying skin was pre-expanded and transferred to repair the large facial defect in 12 cases. The skin pedicle contained the frontal branch of superficial temporal artery and one of main branches of superficial temporal vein. Among the 12 cases, the frontal branch of superficial temporal vein was used as the outflow in 4 cases, and the parietal branch was used as the outflow in 8 cases. The size of the flaps ranged from 3 cm×2 cm to 30 cm×13 cm. The skin pedicles were divided at 3 weeks after the flap transfer. Results: Indocyanine green angiography could clearly showed the course and branching of the superficial temporal artery and vein. Individual differences existed in the location where the frontal branch of the superficial temporal artery entered the forehead. The superficial temporal vein had great variability and did not follow the artery. One patient had expander-related complication, which resulted in 3-cm flap necrosis. The necrotic tissue was debrided and repaired with skin grafting. The other flaps totally survived and the incisions healed by first intention. All patients were followed up 2-24 months, with a median of 11.5 months. The color, texture, and thickness of the flaps matched well with those of recipient sites. Hypertrophic scar was not observed in recipient or donor site. All patients were satisfied with the reconstructive outcomes. Conclusion: Indocyanine green angiography can clearly visualize the course and the branches of the superficial temporal arteries and veins, which can help surgeons understand the position, distribution, and concomitant relationship of the superficial temporal vessels, and make a rational surgical plan of the forehead flap.

Successful Reconstruction of Complex Sacrococcygeal Defects Using Chimeric Perforator Propeller Flap.

BACKGROUND: Complex soft tissue defects, which result from the surgical resection of sacral tumors, manifest as a combination of skin defects, dead space, infection, and prosthesis exposure. Because the traditional musculocutaneous flap lacks flexibility because of the close connection between the skin flap and the muscle component, the musculocutaneous flap is not suitable for reconstructing complex soft tissue defects where the dead space and skin defects are located at different sites. Furthermore, the perforator flap is also not appropriate for reconstructing complex defects because it lacks the muscular component. We considered the possibility of using the chimeric perforator propeller flap for reconstructing complex sacrococcygeal defects. METHODS: This study included 7 patients who underwent, between July 2007 and July 2021, the reconstruction of complex soft tissue defects of the sacrococcygeal region using a chimeric perforator propeller flap. RESULTS: Among the included cases, the etiologies were chordoma (n = 3), sacral tumor (n = 3), and squamous cell carcinoma (n = 1). In all the cases, vacuum-assisted closure therapy was used to treat wound infections before surgery. The average sizes of the skin and muscle flaps were 195.8 cm 2 (range, 100-350 cm 2 ) and 83.6 cm 2 (range, 60-140 cm 2 ), respectively. The superior gluteal artery was the source artery for the chimeric perforator propeller flap. The donor sites were primarily closed in all cases. One patient had delayed wound healing, and the secondary wound healed using conservative dressing changes. The other 6 flaps had no complications. The average follow-up time was 5.3 months (range, 1-9 months). Muscle weakness and compromised ambulation in the affected lower extremities were not observed in any of the patients. Furthermore, all 7 patients had no tumor recurrence, prosthesis exposure, and infection events in the sacrococcygeal region. CONCLUSIONS: The chimeric perforator propeller flap may be an option for reconstructing complex soft tissue defects in the sacrococcygeal region.

Recurrence of Local Kyphosis After Percutaneous Kyphoplasty: The Neglected Injury of the Disc-Endplate Complex.

Background: Recurrent of local kyphosis after percutaneous kyphoplasty (PKP) is rarely reported and discussed. Literatures reported that re-kyphosis is usually a consequence of refractures of augmented or adjacent vertebra. However, whether re-kyphosis should be considered as a complication of refractures and has an impact on clinical efficacy of PKP during follow-up time is unknown. The purpose of this study is to evaluate the related risk factors and clinical significance of the recurrent of local kyphosis in osteoporotic vertebral fracture (OVF) patients without refractures. Patients and Methods: A total of 143 patients who underwent single-level PKP were recruited and assigned into the re-kyphosis group and non-re-kyphosis group. Clinical and radiographic data were collected and compared between the two groups. Then, multivariate logistic regression analyses were conducted to identify the related risk factors. Results: During follow-up, 16 of the 143 patients presented postoperative re-kyphosis. The average local kyphosis angle increased from 11.81±8.60° postoperatively to 25.13±8.91° at the final follow-up which showed a statistically significant difference (p<0.05). Both groups had significant improvements in postoperative visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores compared to their preoperative values (p<0.05). However, in the re-kyphosis group at final follow-up, the VAS and ODI scores showed worsening compared to the postoperative scores. Logistic regression analysis showed that disc-endplate complex injury (OR=17.46, p=0.003); local kyphosis angle correction (OR=1.84, p<0.001); and vertebral height restoration (OR=1.15, p=0.003) were risk factors for re-kyphosis. Conclusion: Re-kyphosis is not rare in patients with osteoporotic vertebral fracture and tends to have an inferior prognosis following PKP surgery. Patients with disc-endplate complex injury and more correction of vertebral height and kyphosis angle are at a higher risk for re-kyphosis after PKP surgery than others.

Prkra Mutation Alters mRNA Expression During Embryonic External Ear Development.

To understand the changes in mRNA expression during the embryonic development of the external mouse ear after the point mutation of the Prkra gene, Prkra short ear mouse model was used to study the development of the embryonic external ear. The tissues of the embryonic external ear were obtained when mouse embryos developed to E15.5 and E17.5. The changes in the mRNA expression profile were detected and analyzed. Find_circ and CIRI2 softwares were used to identify the upregulated and down-regulated expression of mRNA in the experimental and control groups. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes functional annotations were conducted on the differentially expressed mRNA, and the related signal pathways were analyzed after the upregulation and down-regulation of mRNA expression. This study aimed to understand the regulation of mRNA expression in Prkra short-ear mice during the external ear development in embryos. The results showed a correlation between abnormally expressed mRNA and signal pathways and the regulation of the development of the external ear of Prkra short-ear mice, and there were differences in some key regulatory mRNA changes after the Prkra gene point mutation. This study will provide a new clue for the mechanism of mRNA regulating the development of the external mouse ear. The change in mRNA expression profile can also provide clues for studying the biological regulation mechanism of external ear embryonic development.

Effect of Mechanical Tension on the Long-Chain Noncoding RNA Expression Profile of Human Skin Regeneration.

This study investigates the potential gene regulation of long-chain noncoding RNAs (lncRNAs) during skin regeneration by analyzing the changes in the lncRNA expression profile during skin regeneration under mechanical tension. Through the effect of mechanical tension on human skin tissue, the authors observed that after the accelerated differentiation and proliferation of skin epidermal cells, the lncRNA expression profile was compared with that of normal epidermal cells, and differential expression of lncRNA in skin tissue was found. Fifty-three lncRNAs were differentially expressed between the experimental and control groups, and compared with the control group, 22 lncRNAs were upregulated and 31 lncRNAs were downregulated in the experimental group. In addition, through the annotation of the functions of gene ontology and kyoto encyclopedia of genes and genomes, it was further clarified that the main signaling pathway of lncRNAs in the process of skin tissue expansion is involved in the regulation of skin tissue regeneration, and the regulatory network of lncRNAs and microRNAs was established. The results of this study will provide a theoretical basis for the mechanism of lncRNA regulation of skin regeneration, and changes in the lncRNA expression profile can also provide clues for the study of the biological regulation mechanism of skin regeneration.

Changes in the Long Noncoding RNA Expression Profile in the Development of the Embryonic External Ear After BMP5 Gene Mutation.

To understand the role of long noncoding RNA (lncRNA) gene regulation and changes in expression in mouse external ear embryonic development, a BMP5 short ear mouse model was used to measure changes in the lncRNA expression in the outer ear tissues of mouse embryos developed to E15.5 and E17.5 using high-throughput sequencing. The changes in lncRNA expression were identified using find_circ and CIRI2 software, and functional analyses were performed using gene ontology and the Kyoto encyclopedia of genes and genomes annotations of differentially expressed lncRNAs. The results show a correlation between the regulation of lncRNA and some key regulatory lncRNA changes after point mutations in BMP5 . This study provides new insights into the mechanism, by which lncRNAs regulate the development of the mouse's external ear. The change in lncRNA expression profiles can also provide clues for the study of the regulatory mechanisms of external ear embryonic development.

Comparison of Microfat, Nanofat, and Extracellular Matrix/Stromal Vascular Fraction Gel for Skin Rejuvenation: Basic Animal Research.

BACKGROUND: Although stromal vascular fraction (SVF) cells and adipose-derived stem cells have well-defined antiaging effects on skin, certain disadvantages have limited their clinical application. OBJECTIVES: The aim of this study was to evaluate the effects of microfat, nanofat, and SVF-gel in improving ultraviolet (UV)-induced photoaged skin injury in nude mice. METHODS: After successfully establishing a photoaging model by UVA and UVB irradiation in nude mice, the back of each mouse was divided into 2 regions and randomly injected under the dermis with 0.5 mL of microfat, nanofat, SVF-gel, and phosphate-buffered saline. Inflammatory infiltration, dermis thickness, hydroxyproline content, Type I/Type III collagen ratio, elastic fiber morphology, skin cell proliferation, and adipocyte viability were measured. The overall structure of the skin was also observed by scanning electron microscopy. RESULTS: In the microfat group, the grafts survived well, with intact structure and viable adipocytes and little infiltration of inflammatory cells. Microfat promoted skin cell proliferation, collagen content increased, the ratio of Type I and III collagen reversed, and new oxytalan fibers formed, which to some extent improved the photoaging skin. In the nanofat and SVF-gel groups, a large amount of inflammatory cell infiltration and foam cell deposition in the grafts and dermis led to fibrosis and proliferation of skin tissue. Although the skin thickness and collagen content were also increased, these factors did not improve the photoaging skin. CONCLUSIONS: Microfat survives well, and improves photoaged skin injury in nude mice by promoting skin tissue regeneration and supplementing the capacity of subcutaneous adipose tissue.

Changes in the Transcriptome-Associated Co-Expression Profile of Embryonic External Ear Development After the BMP5 Gene Mutation.

This study aimed to perform an association analysis of the full transcriptome in Bmp5 short-ear mice during the development of the external ear in mouse embryos using advanced sequencing techniques. To understand the changes in gene regulation and expression of BMP5 gene mutations involved in the external ear embryonic development of mice, external ear tissues of mouse embryos developed to E15.5 and E17.5 were obtained using a BMP5 short-ear mouse model. The association analysis of the full transcriptome mainly involved the analysis of lncRNA and mRNA associations, the analysis of lncRNA and miRNA associations, the analysis of miRNA and mRNA associations, the analysis of circRNA and mRNA associations and circRNA, miRNA, and mRNA associations. The results showed that regulation of the full transcriptome is associated with external ear development in BMP5 short-ear mouse embryos, and some key regulatory changes in full transcriptome after BMP5 gene point mutation are different. This study will provide a new clue to investigate the mechanism underlying the regulation of mouse external ear development by the full transcriptome.

Point Mutation in Prkra Alters miRNA Expression During Embryonic External Ear Development.

Microtia is a congenital malformation of the external ear that can lead to conductive hearing impairment. In this study, we investigated the role of the Prkra gene in external ear development. We used advanced sequencing techniques to evaluate the differential expression of microRNAs (miRNAs) involved in external ear development in mouse embryos after point mutation in the Prkra gene. The Prkra Little ear mouse model was used to obtain mouse embryos at the E15.5 and E17.5 developmental stages, and changes in miRNA expression profiles were detected. Gene ontology and Kyoto Encyclopedia of Genes and Genomes functional annotations were performed on differentially expressed miRNAs, and existing and new miRNAs were studied. miRNAs were observed to be involved in multiple signaling pathways during the E15.5 and E17.5 developmental stages. The results show a correlation between miRNA regulation and external ear development in Prkra Little ear mice, and differences were detected in key regulatory miRNAs owing to point mutations in the Prkra gene. This study provides new insights into the biological mechanisms through which miRNAs regulate external ear development in mouse embryos. Changes in the mouse miRNA expression profiles can also provide insights into the pathogenesis of human congenital microtia at the level of miRNA regulation.