Exosomal miR-4645-5p from hypoxic bone marrow mesenchymal stem cells facilitates diabetic wound healing by restoring keratinocyte autophagy.

Background: Refractory diabetic wounds are a common occurrence in patients with diabetes and epidermis-specific macroautophagy/autophagy impairment has been implicated in their pathogenesis. Therefore, identifying and developing treatment strategies capable of normalizing epidermis-specific macroautophagy/autophagy could facilitate diabetic wound healing. The study aims to investigate the potential of bone marrow mesenchymal stem cell-derived exosomes (BMSC-exos) from hypoxic conditions as a treatment to normalize epidermis-specific autophagy for diabetic wound healing. Methods: We compared the effects of bone marrow mesenchymal stem cell (BMSC)-sourced exosomes (BMSC-Exos) from hypoxic conditions to those of BMSC in normoxic conditions (noBMSC-Exos). Our studies involved morphometric assessment of the exosomes, identification of the microRNA (miRNA) responsible for the effects, evaluation of keratinocyte functions and examination of effects of the exosomes on several molecules involved in the autophagy pathway such as microtubule-associated protein 1 light chain 3 beta, beclin 1, sequestosome 1, autophagy-related 5 and autophagy-related 5. The experiments used human BMSCs from the American Type Culture Collection, an in vivo mouse model of diabetes (db/db) to assess wound healing, as well as the human keratinocyte HaCaT cell line. In the methodology, the authors utilized an array of approaches that included electron microscopy, small interfering RNA (siRNA) studies, RNA in situ hybridization, quantitative real-time reverse transcription PCR (qRT-PCR), the isolation, sequencing and differential expression of miRNAs, as well as the use of miR-4645-5p-specific knockdown with an inhibitor. Results: Hypoxia affected the release of exosomes from hypoxic BMSCs (hy-BMSCs) and influenced the size and morphology of the exosomes. Moreover, hyBMSC-Exo treatment markedly improved keratinocyte function, including keratinocyte autophagy, proliferation and migration. miRNA microarray and bioinformatics analysis showed that the target genes of the differentially expressed miRNAs were mainly enriched in 'autophagy' and 'process utilizing autophagic mechanism' in the 'biological process' category and miR-4645-5p as a major contributor to the pro-autophagy effect of hyBMSC-Exos. Moreover, mitogen-activated protein kinase-activated protein kinase 2 (MAPKAPK2) was identified as a potential target of exosomal miR-4645-5p; this was confirmed using a dual luciferase assay. Exosomal miR-4645-5p mediates the inactivation of the MAPKAPK2-induced AKT kinase group (comprising AKT1, AKT2, and AKT3), which in turn suppresses AKT-mTORC1 signaling, thereby facilitating miR-4645-5p-mediated autophagy. Conclusions: Overall, the results of this study showed that hyBMSC-Exo-mediated transfer of miR-4645-5p inactivated MAPKAPK2-induced AKT-mTORC1 signaling in keratinocytes, which activated keratinocyte autophagy, proliferation and migration, resulting in diabetic wound healing in mice. Collectively, the findings could aid in the development of a novel therapeutic strategy for diabetic wounds.

Relieving Macrophage Dysfunction by Inhibiting SREBP2 Activity: A Hypoxic Mesenchymal Stem Cells-Derived Exosomes Loaded Multifunctional Hydrogel for Accelerated Diabetic Wound Healing.

Macrophage dysfunction is one of the primary factors leading to the delayed healing of diabetic wounds. Hypoxic bone marrow mesenchymal stem cells-derived exosomes (hyBMSC-Exos) have been shown to play an active role in regulating cellular function through the carried microRNAs. However, the administration of hyBMSC-Exos alone in diabetic wounds usually brings little effect, because the exosomes are inherently unstable and have a short retention time at the wounds. In this study, a multifunctional hydrogel based on gallic acid (GA) conjugated chitosan (Chi-GA) and partially oxidized hyaluronic acid (OHA) is prepared for sustained release of hyBMSC-Exos. The hydrogel not only exhibits needs-satisfying physicochemical properties, but also displays outstanding biological performances such as low hemolysis rate, strong antibacterial capacity, great antioxidant ability, and excellent biocompatibility. It has the ability to boost the stability of hyBMSC-Exos, leading to a continuous and gradual release of the exosomes at wound locations, ultimately enhancing the exosomes' uptake efficiency by target cells. Most importantly, hyBMSC-Exos loaded hydrogel shows an excellent ability to promote diabetic wound healing by regulating macrophage polarization toward M2 phenotype. This may be because exosomal miR-4645-5p and antioxidant property of the hydrogel synergistically inhibit SREBP2 activity in macrophages. This study presents a productive approach for managing diabetic wounds.

Exosomal IRF1-loaded rat adipose-derived stem cell sheet contributes to wound healing in the diabetic foot ulcers.

BACKGROUND: Cell-based therapy has been recognized as a novel technique for the management of diabetic foot ulcers, and cell-sheet engineering leads to improved efficacy in cell transplantation. This study aims to explore the possible molecular mechanism of the rat adipose-derived stem cell (ASC) sheet loaded with exosomal interferon regulatory factor 1 (IRF1) in foot wound healing. METHODS: Rats were rendered diabetic with streptozotocin, followed by measurement of miR-16-5p expression in wound tissues. Relationship between IRF1, microRNA (miR)-16-5p, and trans-acting transcription factor 5 (SP5) was analyzed using luciferase activity, RNA pull-down, and chromatin immunoprecipitation assays. IRF1 was overexpressed in rat ASCs (rASCs) or loaded onto the rASC sheet, and then exosomes were extracted from rASCs. Accordingly, we assessed the effects of IRF1-exosome or IRF1-rASC sheet on the proliferation and migration of the fibroblasts along with endothelial cell angiogenesis. RESULTS: miR-16-5p was poorly expressed in the wound tissues of diabetic rats. Overexpression of miR-16-5p promoted fibroblast proliferation and migration as well as endothelial cell angiogenesis, thus expediting wound healing. IRF1 was an upstream transcription factor that could bind to the miR-16-5p promoter and increase its expression. In addition, SP5 was a downstream target gene of miR-16-5p. IRF1-exosome from rASCs or the IRF1-rASC sheet facilitated the foot wound healing in diabetic rats through miR-16-5p-dependent inhibition of SP5. CONCLUSION: The present study demonstrates that exosomal IRF1-loaded rASC sheet regulates miR-16-5p/SP5 axis to facilitate wound healing in diabetic rats, which aids in development of stem cell-based therapeutic strategies for diabetic foot wounds.

Effectiveness of fractional carbon dioxide laser combined with botulinum toxin type A in a rabbit ear model with the underlying mechanism.

BACKGROUND: Hypertrophic scar (HS) is a common disease in plastic and cosmetic surgery, with limited treatment options, and is a challenge for clinicians. OBJECTIVES: This study aimed to evaluate the efficacy of fractional carbon dioxide (CO2 ) laser combined with botulinum toxin type A (BTXA) in treating HSs in rabbit ears and to provide new strategies for treating HS. METHODS: Twenty-four New Zealand white rabbits with induced HSs were randomly divided into one control and three treatment groups. After 4 weeks of modeling, BTXA (2.0 U) was injected into the HS of the BTXA and combination groups, whereas a fractional CO2 laser (combo mode, deep energy: 12.5 mJ; super energy: 90 mJ) was used in the fractional CO2 laser and combination groups. The laser treatments were repeated after 2 weeks. The HSs in the rabbit ears were observed and photographed 5 weeks after the first treatment. The scar thickness in each group was measured and compared, and the scar elevation index (SEI) was determined using hematoxylin and eosin staining. Collagen content and alignment were observed using Masson's trichrome staining. Western blotting and immunohistochemistry were performed to analyze scar-related protein levels. RESULTS: Hypertrophic scars were reduced in all treatment groups compared with the control group. The combination group had lower scar thickness, SEI, and expression of scar-related proteins in HSs, with an appearance similar to that of normal rabbit ear skin. Furthermore, the fibroblast content and collagen deposition decreased significantly in the combination group (p < 0.001). CONCLUSIONS: Fractional CO2 laser combined with BTXA more effectively reduced HSs by inhibiting fibroblast proliferation, decreasing transforming growth factor-ß1 and α- smooth muscle actin expression, and causing collagen remodeling.

Engineered nanovesicles from stromal vascular fraction promote angiogenesis and adipogenesis inside decellularized adipose tissue through encapsulating growth factors.

Acellular matrix is a commonly used biomaterial in the field of biomedical engineering and revascularization is the key process to affect the effect of acellular matrix on tissue regeneration. The application of bioactive factors related to angiogenesis has been popular in the regulation of revascularization, but the immune system clearance, uncontrollable systemic reactions, and other factors make this method face challenges. Recent reports showed that engineered cells into nanovesicles can reorganize cell membranes and encapsulate cellular active factors, extending the in vitro preservation of cytokines. However, the problems of exogenous biological contamination and tumorigenicity restricted the clinical transformation and wide application of this method. Here, we for the first time engineer stromal vascular fraction (SVF) which is extracted from fat into nanovesicles (SVF-EVs) for angiogenesis in the acellular matrix. SVF-EVs not only promote the migration of vascular endothelial cells in vitro, but also facilitate the lipogenic differentiation of mesenchymal stem cells. In vivo, SVF-EVs enhanced the retention of decellularized adipose tissue after transplanting to the subcutaneous area of nude mice. Immunofluorescence staining further showed that SVF-EVs promoted the formation of vascular networks with large lumen diameter in the grafted acellular matrix, accompanied by adipocyte regeneration peripherally. These findings reveal that SVF-EVs can be a viable method for accelerating revascularization in acellular matrix, and this process of squeezing tissue into nanovesicles shows the potential for rapid clinical transformation.

Soluble microneedle patch with photothermal and NO-release properties for painless and precise treatment of ischemic perforator flaps.

Skin necrosis is the most serious complication of flap plastic surgery, which means the failure of the operation. Systemic administration rarely benefits the local area and can lead to side effects, while topical administration has poor permeability due to the skin barrier function. Currently, few of these common medical interventions can totally respond to the blood supply of the skin after surgery. Herein, a soluble microneedle (MN) patch made of hyaluronic acid was used to target the ischemic area in a painless and precise manner for transdermal drug delivery. Based on the important role of nitric oxide (NO) in angiogenesis, the thermosensitive NO donor (BNN6) and gold nanorods (GNRs) acting as photothermal agents were introduced into the microneedles (MNs). The hyperthermia induced by GNRs under near infrared (NIR, 808 nm) irradiation could enhance the penetration of drugs and facilitate NO release from BNN6. A series of corresponding experiments proved that the system played a significant promotion role in vascular regeneration, providing a painless, precise and NO-assisted treatment method for the ischemic perforator flaps.

Extracellular vesicle-enclosed miR-486-5p mediates wound healing with adipose-derived stem cells by promoting angiogenesis.

Adipose-derived stem cells (ASC) are said to have a pivotal role in wound healing. Specifically, ASC-secreted extracellular vesicles (EV) carry diverse cargos such as microRNAs (miRNAs) to participate in the ASC-based therapies. Considering its effects, we aimed to investigate the role of ASC-EVs in the cutaneous wound healing accompanied with the study on the specific cargo-medicated effects on wound healing. Two full-thickness excisional skin wounds were created on mouse dorsum, and wound healing was recorded at the indicated time points followed by histological analysis and immunofluorescence staining for CD31 and α-SMA. Human skin fibroblasts (HSFs) and human microvascular endothelial cells (HMECs) were co-cultured with EVs isolated from ASC (ASC-EVs), respectively, followed by the evaluation of their viability and mobility using CCK-8, scratch test and transwell migration assays. Matrigel-based angiogenesis assays were performed to evaluate vessel-like tube formation by HMECs in vitro. ASC-EVs accelerated the healing of full-thickness skin wounds, increased re-epithelialization and reduced scar thickness whilst enhanced collagen synthesis and angiogenesis in murine models. However, miR-486-5p antagomir abrogated the ASC-EVs-induced effects. Intriguingly, miR-486-5p was found to be highly enriched in ASC-EVs, exhibiting an increase in viability and mobility of HSFs and HMECs and enhanced the angiogenic activities of HMECs. Notably, we also demonstrated that ASC-EVs-secreted miR-486-5p achieved the aforesaid effects through its target gene Sp5. Hence, our results suggest that miR-486-5p released by ASC-EVs could be a critical mediator to develop an ASC-based therapeutic strategy for wound healing.

[Clinical application of modified kite flap in treatment of divided nevus of lateral canthus].

OBJECTIVE: To investigate the effectiveness of modified kite flap in repair of soft tissue defect after divided nevus of lateral canthus excision. METHODS: Between October 2010 and April 2018, 20 children (20 eyes) with divided nevus of lateral canthus were admitted. There were 13 boys and 7 girls, with an average age of 7.9 years (mean, 4-14 years). There were 11 cases of moderate range lesions (maximum diameter, 1.5-2.0 cm) and 9 cases of small range lesions (maximum diameter, <1.5 cm). After excising the divided nevus of lateral canthus, the area of soft tissue defect ranged from 0.72 to 3.23 cm2。The modified kite flap was used to reconstruct the structure and shape of lateral canthus. RESULTS: There were 16 cases of mixed nevus and 4 cases of intradermal nevus. The flaps survived and the incisions healed by the first intention. The patients were followed up 12-22 months (mean, 13.6 months). There was no malformation, valgus, exposure keratitis, or obvious scar. No malignant transformation occurred or nevus recurred during follow-up. At last follow-up, the effectiveness was rated as excellent in 16 cases, good in 3 cases, and poor in 1 case. CONCLUSION: The modified kite flap can repair the soft tissue defect after excising the divided nevus of lateral canthus, and obtain the good appearance and function of lateral canthus.

[The application of modified rhomboid flap in repairing facial skin and soft tissue defect].

Objective: To explore the effectiveness of modified rhomboid flap for repairing facial skin and soft tissue defect. Methods: Between January 2016 and May 2018, 23 patients with facial skin and soft defect were repaired by the modified rhomboid flap. There were 10 males and 13 females with the median age of 27 years (range, 11-72 years). The primary tumor included pigmented nevus in 18 cases, basal cell carcinoma in 4 cases, and squamous cell carcinoma in 1 case. The defect location was nose in 8 cases, cheek in 4 cases, malar in 6 cases, forehead in 2 cases, and upper lip in 3 cases. The defect ranged from 0.8 cm×0.8 cm to 3.9 cm×3.9 cm. According to the location and size of facial tumors, the resection area of square lesions was designed. According to the mobility of surrounding tissues and the direction of dermatoglyphic lines, the rhomboid flaps with an angle of 45-60° was designed to repair the defect by tension-free rotation. Results: All the flaps survived and the incision healed by first intension. All patients were followed up 3-15 months (mean, 7.3 months). During follow-up, no tumor reoccurred; the color and texture of the flaps were similar with surrounding tissue. There was no obvious scar hyperplasia, nor traction of adjacent normal tissues, and patients were satisfied with the appearance. Conclusion: The application of modified rhomboid flaps in repairing facial skin and soft tissue defects caused by resection of round facial tumor has the advantages of flexible design, simple manipulation, and less trauma.

[Effectiveness of modified transsection and longitudinal suture in epicanthoplasty].

Objective: To introduce a modified transsection and longitudinal suture in epicanthoplasty and summarize its effectiveness. Methods: The clinical data of 119 patients underwent epicanthoplasty with modified transsection and longitudinal suture and with a follow-up time over 6 months between February 2014 and December 2016 were retrospectively analyzed. There were 8 males and 111 females with an average age of 22.7 years (range, 18-38 years). The epicanthus was as eyebrow type in 12 cases, as eyelid type in 57 cases, as tarsalis type in 39 cases, and as backward type in 11 cases. The narrow degree of epicanthus included mild (the lacrimal caruncle covered size was less than 1/3) in 42 cases, moderate (the lacrimal caruncle covered size was between 1/3 and 2/3) in 58 cases, and severe (the lacrimal caruncle covered size was over 2/3) in 19 cases. One hundred and thirteen patients were treated by blepharoplasty at the same time. The new canthus was located on the basis of the inner canthus physiological aesthetics. Through a short transverse incision, dislocated orbicularis oculi muscle near medial canthal ligament and the fiber between the medial canthal ligament and skin were completely released; then the medial canthal ligament was shortened precisely and the incision was tension-free sutured followed the Langer's line near eyes. Results: All the incisions healed by first intention. All patients were followed up 6 months to 2 years (mean, 8.6 months). The bilateral hypertrophic scar on both bilateral medial canthal incisions happened in 3 patients at 3-6 months after operation; and the scarring gradually subsided at 10 months after the diprospan injections and the siliconegel and carbon dioxide laser treatment. Good effectiveness were obtained in the other patients, whose inner intercanthal distance significantly narrowed, both of the horizontal lid fissure length increased, the lacrimal caruncle fully exposed, and no obvious scar could be seen. Conclusion: The modified transsection and longitudinal suture in epicanthoplasty has the advantages of simple design, easy operation, minimally invasive, inconspicuous scar, and obvious, stable, and lasting postoperative effectiveness.

[Clinical efficacy analysis of myocutaneous flap in blepharoplasty].

Objective: To introduce the myocutaneous flap in blepharoplasty and summarize its clinical efficacy. Methods: Between January 2013 and March 2016, 1 560 patients underwent blepharoplasty with myocutaneous flap. Of them, 158 patients were followed up over 6 months and included in the study. There were 18 males and 140 females with the average age of 23.4 years (range, 18-35 years). The unilateral side was involved in 13 cases and bilateral sides in 145 cases. The patients had narrow double eyelid, shallow double eyelid, single eyelid, bloated upper eyelid, and upper eyelid skin relaxation. During operation, the tissue between the orbicular muscle of eye and the tarsus was trimmed layer by layer; the orbicularis oculi muscle, capillary network, and the front fascia of tarsus were retained, and the full-thickness skin, muscle, and the front fascia of tarsus were sutured by anatomical apposition. Results: Incision healed at stage I. All patients were followed up 6 months to 2 years (mean, 8.3 months). During follow-up period, shallow or extinctive double-eyelid line was observed in 9 cases (12 eyes), and satisfactory results were achieved after trimming front fascia of tarsus and suturing. Good clinical results were obtained in the other patients, who had natural and coherent double eyelid without obvious scar or depression at resection margin. Conclusion: Myocutaneous flap for blepharoplasty has many advantages of fast recovery, little wound, light swelling, permanent effects, and good appearance.

[CLINICAL STUDY ON ZYGOMATIC SPINDLE-SHAPED OSTEOTOMY AND INTERNAL PUSH OF TITANIUM SCREW ANCHOR IN TREATMENT OF PROMINENT MALAR].

OBJECTIVE: To explore the effectiveness of the zygomatic spindle-shaped osteotomy and internal push of titanium screw anchor for prominent malar. METHODS: Between July 2011 and January 2015, 58 patients with prominent malar underwent zygomatic spindle-shaped osteotomy and internal push of titanium screw anchor. There were 3 males and 55 females, aged 18-33 years (mean, 23 years). They had congenital bilateral prominent malar. Preoperative anteroposterior, lateral, supine position, 45" oblique photographs of the face were taken, three-dimensional CT reconstruction of face was performed. Simple prominent malar was observed in 30 cases, and prominent malar and zygomatic arch in 28 cases; zygomatic bone and zygomatic arch were symmetrical in 51 cases, and asymmetrical in 7 cases. RESULTS: All patients obtained stage I incision healing after operation, without infection or hematoma. Numbness of the upper lip occurred in 2 cases, limitation of mouth opening in 1 case, and nasolabial fold deepening in 1 case, which recovered spontaneously after 3 months. Fifty-eight cases were followed up 6-12 months (mean, 10 months). Zygomatic narrow spacing was 10.6-13.9 mm (mean, 11.2 mm). No ptosis of facial soft tissue, zygomatic step, facial nerve injury, raising eyebrow, dysfunction of eyes closure, or temporomandibular joint disorder syndrome occurred. Good bone healing was obtained, zygomatic facial sensation had no obvious abnormality, all patients were satisfied with the improvement of appearance. CONCLUSION: Zygomatic spindle-shaped osteotomy and internal push titanium screw anchor can effectively reduce the cheekbones, and maintain the natural curve of zygomatic body and zygomatic arch. Because of simple operation, less complications, and excellent results, it is an ideal plasty.

Prognostic value of cancer stem cell marker CD133 expression in esophageal carcinoma: A meta-analysis.

CD133 has been identified as a putative neoplastic stem cell marker in esophageal carcinoma. However, the prognostic value of CD133 overexpression in patients with esophageal carcinoma remains controversial. A meta-analysis of previous studies was performed, in order to assess the association of CD133 overexpression with the clinicopathological characteristics of esophageal carcinoma patients. A total of 7 studies, including 538 patients, were subjected to the final analysis. Our results indicated that a positive CD133 expression was significantly associated with lymph node metastasis [odds ratio (OR)=3.09, 95% confidence interval (CI): 1.93-4.95; P<0.00001], clinical stage (OR=4.26, 95% CI: 1.55-11.73; P=0.005) and histopathological grade (OR=2.40, 95% CI: 1.16-4.94; P=0.02). There was no statistically significant association of CD133 with depth of invasion (OR=1.89, 95% CI: 0.42-8.43; P=0.41). Based on the results of this study, we concluded that CD133 is an efficient prognostic factor in esophageal carcinoma. Higher CD133 expression is significantly associated with lymph node metastasis, clinical stage and histopathological grade.

Cell-assisted lipotransfer in the clinical treatment of facial soft tissue deformity.

Cosmetic surgeons have experimented with a variety of substances to improve soft tissue deformities of the face. Autologous fat grafting provides significant advantages over other modalities because it leaves no scar, is easy to use and is well tolerated by most patients. Autologous fat grafting has become one of the most popular techniques in the field of facial plastic surgery. Unfortunately, there are still two major problems affecting survival rate and development: revascularization after transplantion; and cell reservation proliferation and survival. Since Zuk and Yosra developed a technology based on adipose-derived stem cells and cell-assisted lipotrophy, researchers have hoped that this technology would promote the survival and reduce the absorption of grafted fat cells. Autologous adipose-derived stem cells may have great potential in skin repair applications, aged skin rejuvenation and other aging-related skin lesion treatments. Recently, the study of adipose-derived stem cells has gained increased attention. More researchers have started to adopt this technology in the clinical treatment of facial soft tissue deformity. The present article reviews the history of facial soft tissue augmentation and the advent of adipose-derived stem cells in the area of the clinical treatment of facial soft tissue deformity.

Les plasticiens ont mis diverses substances à l'essai pour corriger les malformations des tissus mous de la face. La greffe de graisse autologue comporte d'importants avantages par rapport aux autres modalités, car elle ne laisse aucune cicatrice, est facile à utiliser et est bien tolérée par la plupart des patients. C'est désormais l'une des techniques les plus populaires en chirurgie plastique de la face. Malheureusement, deux grands problèmes influent encore sur le taux de survie et le développement : la revascularisation après la greffe ainsi que l'inventaire, la prolifération et la survie des cellules. Depuis que Zuk et Yosra ont mis au point une technologie qui repose sur les cellules souches adipeuses et la lipotrophie cellulaire, les chercheurs espèrent que cette technologie permettra de promouvoir la survie et de réduire l'absorption des cellules adipeuses greffées. Les cellules souches adipeuses autologues ont peut-être plus de potentiel pour les applications de réparation cutanée, le rajeunissement de la peau vieillissante et d'autres traitements des lésions cutanées liées au vieillissement. L'étude des cellules souches adipeuses a commencé à susciter l'attention. Plus de chercheurs ont commencé à adopter cette technologie pour le traitement clinique des malformations des tissus mous de la face. L'histoire de l'augmentation des tissus mous de la face et l'utilisation des cellules souches adipeuses pour le traitement clinique des malformations s'y rapportant sont analysées dans le présent article.

[The application of facial liposuction and fat grafting in the remodeling of facial contour].

OBJECTIVE: To investigate the application of facial liposuction and fat grafting in the remodeling of facial contour. METHODS: From Nov. 2008 to Mar. 2014, 49 cases received facial liposuction and fat grafting to improve facial contours. Subcutaneous facial liposuction with tumescent technique and chin fat grafting were performed in all the cases, buccal fat pad excision of fat in 7 cases, the masseter injection of botulinum toxin type A in 9 cases, temporal fat grafting in 25 cases, forehead fat grafting in 15 cases. RESULTS: Marked improvement was achieved in all the patients with stable results during the follow-up period of 6 - 24 months. Complications, such as asymmetric, unsmooth and sagging were retreated with acceptance results. CONCLUSION: Combination application of liposuction and fat grafting can effectively and easily improve the facial contour with low risk.

Lapatinib alters the malignant phenotype of osteosarcoma cells via downregulation of the activity of the HER2-PI3K/AKT-FASN axis in vitro.

Lapatinib, an inhibitor of human epidermal growth factor receptor 2 (HER2) phosphorylation, has been reported to inhibit several types of tumors such as HER2-overexpressing breast cancer. However, the effect of lapatinib on the malignant phenotype of human osteosarcoma (OS) cells and the potential molecular mechanisms remain unclear. To elucidate the effect of lapatinib on OS, two OS cell lines, U2-OS and MG-63, were utilized in the present study. Various concentrations of lapatinib were used to treat OS cells for different time durations. Cell proliferation was evaluated by MTT and colony formation assays. Flow cytometry (FCM) was used to evaluate cell apoptosis. Wound healing and Transwell invasion assays were performed to examine the migratory and invasive abilities of the cells. To investigate the possible molecular mechanisms involved, the expression of p-HER2, phosphatidylinositol 3-kinase (PI3K), p-AKT, AKT and fatty acid synthase (FASN) protein was detected by western blotting. MTT assays showed that lapatinib inhibited the proliferation of U2-OS and MG-63 cells in a dose- and time-dependent manner, and the rate of colony formation of the lapatinib-treated cells was significantly lower when compared to those cells not treated with lapatinib in both cell lines. FCM assay revealed a significantly higher apoptotic rate in the lapatinib-treated OS cells. Wound healing and Transwell invasion assays revealed that the migratory and invasive abilities of OS cells were significantly inhibited by lapatinib (P<0.05). Western blotting showed that lapatinib suppressed the activity of HER2-PI3K/AKT-FASN in U2-OS and MG-63 cells in vitro. These results suggest that lapatinib may alter the malignant phenotype of OS cells via downregulation of the activity of the HER2-PI3K/AKT-FASN signaling pathway in vitro. Thus, lapatinib may be an effective chemotherapeutic agent for the treatment of osteosarcoma.

[Topical application of leptin promotes burn wound healing in rats].

OBJECTIVE: To investigate the effect of topical application of leptin in promoting burn wound healing in rats. METHODS: Four parallel second-degree burn wounds induced on the back of 18 Wistar rats were divided into leptin treatment group (treated with topical application of 400 ng/ml leptin dissolved in PBS) and control group (treated with PBS). The time of wound healing was recorded, and the wound area that was not healed was measured at 3, 7, 11, 15, and 19 days after burns. The tissue at the peripheries of the wound was sampled at 7, 14 and 21 days after burns for pathological examination with HE staining and immunohistochemistry for proliferating cell nuclear antigen (PCNA) to evaluate the proliferation of keratinocytes. RESULTS: Compared with the control group, leptin-treated wounds showed a shorter time (by 2-3 days) of wound healing, and significant differences were found between the two groups in healing at 7, 11, 15, and 19 days after burns. HE staining and immunohistochemistry revealed a faster rate of epidermis growth and a greater thickness of the cuticular layer in leptin-treated wounds at 7, 14 and 21 days after burns. PCNA positivity in the keratinocytes was stronger in leptin-treated wounds than in the control wounds at 7 and 14 days, but no such distinct difference was noted at 21 days between the two groups. CONCLUSION: Topical application of leptin can promote re-epithelization in burn wounds to shorten the wound healing time of burns.

[Progress of autologous fat grafting in clinical applications of the face].

OBJECTIVE: To review the progress of autologous fat grafting of the face and outline different arguments in this field. METHODS: Recent literature concerning autologous fat grafting of the face was reviewed and analyzed. RESULTS: The applications and techniques for autologous fat grafting have been matured increasingly. It not only can adjust the proportion of facial contours, restore tissue volume, but also can improve the local skin texture. Reliable clinical results have achieved in facial augmentation and rejuvenation. Although there are arguments about donor site, harvesting technique, processing technique, and grafting technique, the basic principle is the same. CONCLUSION: From the perspective of evidence-based medicine, clinicians are rich in clinical experience, but objective evidence is insufficient. So further researches should be carried to look for scientific evidences.

[Clinical application of three-dimensional reconstruction of CT images in treating mandibular angle hypertrophy].

OBJECTIVE: To investigate the clinical directive significance of three-dimensional reconstruction of CT in treating mandibular angle hypertrophy. METHODS: Between March 2009 and January 2011, 18 patients with mandibular angle hypertrophy were treated using the three-dimensional reconstruction technology of CT. All patients were female, aged 20-36 years with an average of 25 years. Eighteen patients included: 14 single mandibular angle hypertrophy, 3 mandibular angle hypertrophy with masseter hypertrophy, and 1 mandibular angle hypertrophy with bilateral asymmetry; 6 cases of ptosis of mandibular angle, 9 cases of prominent mandibular angle, and 3 cases of introversive mandibular angle. According to the types of mandibular angle hypertrophy, the surgical methods could be correctly chosen. The procedure was planned and simulated; the osteotomy line was marked and the osteotomy was measured on the workstations of three-dimensional reconstruction. RESULTS: No fracture of mandible occurred in the operation. Facial nerve temporary attack occurred in 1 case and recovered at 3 months after operation. All patients were followed up 6-12 months (mean, 7.6 months). After 6 months of operation, the effectiveness was satisfactory in 15 cases, basically satisfactory in 2 cases, and unsatisfactory in 1 case (bilateral asymmetry). CONCLUSION: Based on three-dimensional reconstruction technology of CT, surgical design performed on the model will promote the accuracy of operation. Basically symmetrical appearances can be achieved with satisfactory results.