Hydration effect and molecular geometry conformation as critical factors affecting the longevity stability of G4-structure-based supramolecular hydrogels.

Nucleoside-derived supramolecular hydrogels based on G4-structures have been extensively developed in the biomedical sector and recognized for superior excellent biocompatibility and biodegradability. However, limited longevity and stability present a significant challenge. Chemical modifications in the molecular structure have been shown to enhance the longevity stability of G4-structure-based supramolecular hydrogels, but the precise way in which the molecular structure impacts the stability of the G4-structures and consequently affects the properties of the hydrogel remains to be elucidated. This issue represents a notable challenge in the field, which restricts their further applications to some extent. In this study, single crystals of Gd, αGd and αGd* were cultivated and compared with G. Notably, before this study, the single crystal structures of all natural nucleosides, with the exception of Gd, had been determined. The investigation into the molecular structure and supramolecular self-assembly properties of four guanosine analogs at the atomic scale revealed that the formation of G-quartets is critical for their ability to form hydrogels. The stability of the sugar ring geometry conformation (an intrinsic factor) and the disorder and strength of the hydration effect (extrinsic factors) are vital for maintaining the stability of the G4-structures. The rapid cooling changes the molecular geometry conformation, and the organic solvent changes the hydration effect, which can improve the longevity stability of G4-structure-based supramolecular hydrogels instead of chemical modifications. Consequently, the lifespan of the hydrogels was extended from 2 h to over one week. This advancement is expected to offer significant insights for future research in designing and developing G4-structure-based supramolecular hydrogels.

The Effect of Botulinum Toxin Type A in the Autologous Fat Grafting: A Review.

BACKGROUND: Autologous fat grafting is a widely used technique in plastic and reconstructive surgery for soft tissue augmentation. Despite its advantages, the primary limitation is the unpredictable retention rate of transplanted fat. Recent studies suggest that botulinum toxin type A (BTX-A) can enhance fat graft survival by promoting angiogenesis and muscle paralysis. AIMS: This review explores the potential of BTX-A as an adjuvant in autologous fat grafting, providing insights into its mechanisms, benefits, and the need for further clinical validation. PATIENTS/METHODS: A literature review was conducted using PubMed, Web of Science, MEDLINE, and Embase. Keywords related to BTX-A, fat grafting, fat graft survival, and angiogenesis were used. Comparative studies reporting histological changes following BTX-A application in fat grafting were included. Exclusion criteria involved case reports with fewer than three animals, reviews, and letters. RESULTS: The initial search yielded 108 articles, with seven experimental studies meeting the criteria. These studies demonstrated that BTX-A enhances fat graft retention by promoting vascularization and adipose-derived stem cell differentiation. However, these results are mainly based on small animal models. CONCLUSIONS: While BTX-A shows promise in improving autologous fat grafting outcomes, its efficacy and safety in humans need validation through large-scale clinical trials. Translating these preclinical findings into human trials is crucial to establish standardized protocols and optimize clinical outcomes. Future research should focus on optimizing dosage and injection sites, conducting long-term follow-up studies, and performing multicenter trials to verify the findings.

Comparison of different thread products for facial rejuvenation: Materials and barb designs.

BACKGROUND: In recent years, the thread-lifting technique has become widely used in clinical settings. Several thread products are used in clinical practice, and there are many differences between products in terms of many aspects. METHODS: Six commercial thread products were collected and evaluated. The general structure, microstructure, elastic modulus, and strength were evaluated using microscopies and tensile testing in vitro. Seventy-two female rats were divided into six groups. Tissue samples were harvested and histologically evaluated at 1st, 4th, 8th, and 12th week using hematoxylin and eosin and Masson's trichrome staining. RESULTS: There were differences between products in terms of barb shape, microstructure, elasticity, and strength, and that could be attributed to the materials and barb structures. All threads showed good biological safety, and the density of collagen area in the dermis was increased compared to that in the control group. CONCLUSIONS: This study provided an objective evaluation of barbed thread products, which indicated that all products can be used safely with certain effects in different indications.

A simple method for fabricating drugs containing a cis-o-diol structure into guanosine-based supramolecular hydrogels for drug delivery.

Supramolecular hydrogels are attractive biomaterials for local drug delivery owing to their excellent self-healing, injectable, biodegradable, and biocompatible properties. However, traditional drug-loading approaches based on non-covalent encapsulation and covalent bonding have shown problems such as rapid or difficult drug release, complex reaction processes, low reaction efficiency, and decreased drug activity. Therefore, there is a need to find a simple and efficient method to load drugs into hydrogels, which possess stable drug release ability without impairing drug efficacy. In this study, we introduce dynamic borate ester bonds via a simple one-pot method to load cis-o-diol-containing drugs into guanosine (G)-based supramolecular hydrogels. The experimental results confirm that the dynamic covalent borate ester bonds are formed based on the cis-o-diol groups of the drug and the G in these hydrogels. Meanwhile, the as-prepared G-based hydrogels not only possess self-healing properties and injectability but also have satisfactory biodegradability and biocompatibility. Additionally, the drug can be released from the G-based hydrogel according to the pH-responsive cleavage of the borate ester bonds without affecting drug activity. Overall, these results indicate that the simple one-pot method of utilizing the dynamic borate bond can provide a valuable reference for the design of hydrogel dosage forms.

Protocatechuic Acid-Based Supramolecular Hydrogel Targets SerpinB9 to Achieve Local Chemotherapy for OSCC.

Protocatechuic acid (PCA) is a natural phenolic acid present in daily vegetables and fruits. Notably, PCA was demonstrated to inhibit the biological function of SerpinB9 (Sb9) and exhibit an excellent antitumor effect, showing great potential in cancer treatment. However, the short half-life time limits PCA's wide application against cancers. To overcome this shortage of PCA, we integrated PCA and another natural product with strong self-assembling properties, isoguanosine (isoG), to develop a novel multifunctional supramolecular hydrogel with good biocompatibility and injectability, which remarkably lengthens the releasing time of PCA and exerts considerable anticancer effects in vitro and in vivo. Besides, we surprisingly found that PCA could not only target Sb9 but also restrain cancer development through activating the JNK/P38 pathway, decreasing the ROS level, and repairing cancer stemness. In all, our results demonstrate that this PCA-based hydrogel could act as a multifunctional hydrogel system equipped with considerable anticancer effects, providing potential local administration integrating with targeted therapy and chemotherapy in one simple modality.

Effects of macrophage regulation on fat grafting survival: Improvement, mechanisms, and potential application-A review.

BACKGROUND: Autologous fat grafting has become a popular tool in plastic surgery to solve soft tissue defects and achieve skin rejuvenation, but the volume loss after transplantation remains a disturbing problem. In recent years, some new strategies have improved the outcome to some extent, but the fat graft retention is still far from ideal, so there remains a wide development prospect in this field. Macrophages are closely related to the local microenvironment and tissue regeneration, and their role in fat grafting has been increasingly highlighted. AIMS: This article was aimed to review the efficacy, possible mechanisms, and potential application of macrophage regulation on fat grafting, as well as concerns and future perspectives of this filed. METHODS: A retrospective review of the published data was conducted. RESULTS: Most studies indicated that up-regulating M2 macrophages during fat grafting would improve fat retention via promoting neovascularization. M2 macrophages could secrete several pro-angiogenic factors, accelerate extracellular matrix (ECM) remodeling, and directly function on endothelial cells to encourage vascular expansion. In addition, macrophages could influence the proliferation, apoptosis, and adipogenic differentiation of preadipocytes. CONCLUSIONS: During autologous fat grafting, appropriately regulating macrophages may become a promising method to increase fat retention. Nevertheless, the M2 macrophage polarizing agents, treatment opportunity, and contraindications require further discussion. We hope our work could promote more in-depth studies in this field, and we are looking forward to a standard procedure for the macrophage therapy in clinical practice.

Topographic Anatomy of the Zygomatico-Orbital Artery: Implications for Improving the Safety of Temporal Augmentation.

BACKGROUND: Anatomical knowledge of the zygomatico-orbital artery and its most relevant clinical applications is essential for ensuring the safety of filler injection into the temporal region. The purpose of this study was to provide the precise position, detailed course, and relationship with surrounding structures of the zygomatico-orbital artery. METHODS: Fifty-eight patients who underwent head contrast-enhanced three-dimensional computed tomography and 10 fresh frozen cadavers were investigated. RESULTS: The zygomatico-orbital artery was identified in 93 percent of the samples in this work. Ninety-four percent of the zygomatico-orbital arteries derived directly from the superficial temporal artery, and the remaining arteries started from the frontal branch of the superficial temporal artery. According to the origin of the zygomatico-orbital artery, it was classified into type I and type II. Type I arteries were then classified into three subtypes. The trunk of the zygomatico-orbital artery was located between the deep temporal fascia and the superficial temporal fascia. Deep branches of the zygomatico-orbital artery pierced the superficial layer of the deep temporal fascia. The zygomatico-orbital artery originated from 11.3 mm in front of the midpoint of the apex of the tragus, and most of its trunks were located less than 20.0 mm above the zygomatic arch. The mean diameter of the zygomatico-orbital artery was 1.2 ± 0.2 mm. There were extensive anastomoses between the zygomatico-orbital artery and various periorbital arteries at the lateral orbital rim. CONCLUSION: The precise anatomical knowledge of the zygomatico-orbital artery described in this study could be helpful for cosmetic physicians for improving the safety of temporal augmentation.

Quantifiable clinical efficacy of injectable porcine collagen for the treatment of structural dark circles.

BACKGROUND: Dark circles are one of the most perplexing cosmetic problems for modern people. Nowadays, a new porcine collagen filler has been popular in China and many countries and has high safety. AIMS: The purpose of this study is to explore and quantify the efficacy of this collagen filler in treating structured dark circles objectively and systematically. METHODS: This is a prospective study. Twenty patients were included and took standard facial photographs at preoperative (Tp), immediately postoperative (T0), 1 week (T1), 2 weeks (T2), 4 weeks (T4), 8 weeks (T8), and 12 weeks (T12). The efficacy was quantified by measuring the depression of the tear trough and infraorbital melanin content. Three dermatologists blinded to the treatment were responsible for completing the subjective evaluations. RESULTS: The depression volume, depression-affected area, and depression maximum depth of the tear trough decreased significantly immediately postoperation, and then all values increased slowly with time (P <.05). After 3-month observation, we found that the residual effect of the treatment is 45.08% ± 15.53% (T8) and 17.37% ± 16.79% (T12). The melanin contents at the medial point (A), the middle point (B), and the lateral point (C) all decreased instantly after injection (A: 8.23% ± 5.07%, B: 6.29% ± 5.05%, C: 5.11% ± 5.44% ), which suggested that collagen filler had an instant covering effect for structural dark circles. Patients showed only slight redness and swelling after the treatment. CONCLUSION: Collagen filler is a very effective treatment method for structural dark circles. Besides, it may also have a certain therapeutic effect on the other three dark circles types.

The Aesthetic Concerns of Botulinum Toxin Type A in the Treatment of Neck Wrinkles: A Systematic Review.

BACKGROUND: The aged and unattractive appearance of the neck has a profound impact on the overall youthfulness and attractiveness of the face. Neck wrinkles are one of the manifestations of neck skin aging. Botulinum toxin type A (BTX-A) represents an effective means for aesthetic neck rejuvenation as novel facial rejuvenation technologies are progressively developed. OBJECTIVES: The objective of this article was to review the pertinent clinical literature for descriptions of BTX-A treatments and evaluations of their efficacy and safety for neck wrinkles. METHODS: The Web of Science, PubMed, EMBASE, Cochrane Library, and SCOPUS databases were searched from inception to April 30, 2020, for the existing literature, which is presented along with the authors' experience with neck wrinkles. RESULTS: Overall, 112 women between 24 and 65 years of age were included in 3 studies of monotherapy and 2 studies of multimodal combination therapy. BTX-A has been reported in combination with other approaches, including intensity focused ultrasound, cohesive polydensified matrix hyaluronic acid, and microfocused ultrasound. Only 1 of the 3 reports on monotherapy had a less than 50% satisfaction and improvement rate. Overall, BTX-A attained high patient satisfaction without serious and persistent side effects, notwithstanding the relatively limited sample size. CONCLUSIONS: The existing research cannot strongly prove the aesthetic effect of BTX-A in neck wrinkles. However, BTX-A is probably an effective technology in response to the growing demand for neck wrinkle treatment, whether in a single treatment or combined treatment.

Down-regulation of miR-200c associates with poor prognosis of oral squamous cell carcinoma.

BACKGROUND: MicroRNAs (miRNAs) are considered as promising cancer biomarkers. The aim of the present study is to investigate the prognostic significance of miR-200c in patients with oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Quantitative real-time PCR (qRT-PCR) was used to determine the expression levels of miR-200c in 204 pairs of OSCC and adjacent noncancerous. Correlations between miR-200c expression levels and clinicopathological characteristics were investigated. Survival analysis was performed using the Kaplan-Meier method and log-rank test. Multivariate analysis of the prognostic factors was performed with a Cox proportional hazards regression model. RESULTS: The expression of miR-200c was significantly down-regulated in OSCC tissues compared with adjacent non-tumor tissues (p < 0.0001). Low expression of miR-200c in tumor tissues was significantly correlated with the positive N classification (p = 0.013), advanced TNM stage (p = 0.007) and poor differentiation grade (p = 0.026). Lower miR-200c expression in patients was significantly associated with poor recurrence-free survival (RFS, p = 0.0003) and overall survival (OS, p = 0.0026). Multivariate analysis confirmed that low miR-200c expression was an independent predictor for poor RFS (hazard ratio (HR) 1.705, 95% CI 1.136-2.56, p = 0.01) and OS (HR 1.669, 95% CI 1.03-2.703, p = 0.037) in patients with OSCC. CONCLUSION: Our results suggest that the miR-200c might be a potential prognostic biomarker for OSCC.

Prospective application of exosomes derived from adipose-derived stem cells in skin wound healing: A review.

BACKGROUND: Wound healing has always been an intractable medical problem for both clinicians and researchers and a burden for patients both physically and financially. Poor wound healing at the injury site, especially in an exposed site, is associated with an unappealing esthetic appearance in patients and also results in a bad skin barrier, tissue infection and necrosis, loss of main function in extreme cases and other serious local and systemic consequences. There is a crucial and urgent need for newer, more efficacious methods for enhancing the healing process to achieve optimal outcomes morphologically and functionally. Recent advances have focused on developing therapies that promote tissue regeneration through positively activating the mechanism of tissue repair. Given the increasing high-quality studies concerning exosomes derived from adipose-derived stem cells (ADSCs-Exos), their potential use in accelerating or supporting the wound healing process has gained increasing attention in recent years. AIMS: In this review, we present an overview of the recent advances in the field of ADSCs-Exos and investigate their benefit in wound healing for skin regeneration with the expectation of providing a perspective on how to best utilize this powerful cell-free therapy in the future. METHODS: A retrospective review of the published data was conducted. RESULTS: Most studies have shown the possible roles of ASCs-derived exosomes (ADSCs-Exos) in cutaneous wound healing through regulation of the inflammatory response and promotion of cell proliferation, migration, differentiation, angiogenesis and matrix reconstruction to provide a new perspective strategy for the use of ASCs-Exos in skin wound healing. CONCLUSION: ADSCs-Exos are likely to achieve the best functionally and cosmetic skin wound healing while avoiding undesirable consequences. ADSCs-Exos represent a novel therapeutic tool in soft tissue repair; however, further randomized, double-blind, comparative clinical trials must be performed to determine the specific mechanisms, safety and other relevant cosmetic concerns.