An injectable bioactive dressing based on platelet-rich plasma and nanoclay: Sustained release of deferoxamine to accelerate chronic wound healing

Delayed diabetic wound healing has placed an enormous burden on society. The key factors limiting wound healing include unresolved inflammation and impaired angiogenesis. Platelet-rich plasma (PRP) gel, a popular biomaterial in the field of regeneration, has limited applications due to its non-injectable properties and rapid release and degradation of growth factors. Here, we prepared an injectable hydrogel (DPLG) based on PRP and laponite by a simple one-step mixing method. Taking advantages of the non-covalent interactions, DPLG could overcome the limitations of PRP gels, which is injectable to fill irregular injures and could serve as a local drug reservoir to achieve the sustained release of growth factors in PRP and deferoxamine (an angiogenesis promoter). DPLG has an excellent ability in accelerating wound healing by promoting macrophage polarization and angiogenesis in a full-thickness skin defect model in type I diabetic rats and normal rats. Taken together, this study may provide the ingenious and simple bioactive wound dressing with a superior ability to promote wound healing.

Research progress of scaffolds for promoting the vascularization of regenerated dental pulp / 口腔疾病防治

@#Endothelial regeneration is a research hotspot in the field of dental pulp. The regeneration of endodontic blood flow is the bottleneck of dental pulp regeneration, and the applied scaffold material is the key to revascularization. Stent materials were reviewed. The literature review Results show that, depending on the source of the stent material used for endodontic revascularization, there are mainly natural, synthetic and composite materials. The natural scaffold materials used for vascular regeneration include chitosan, hyaluronic acid, bacterial cellulose, and proanthocyanidin; artificial scaffold materials include hydrogel, cryogel, and electrospinning. The bionic composite scaffold system with a double-layer tubular structure is low immunogenicity and good biocompatibility. Studies on the scaffold materials of bionic extracellular matrix, such as injectable hydrogels/microspheres, have promoted the development of dental pulp regeneration, that is, uniformly distributed scaffold materials in the root canal promote the generation of pulp-like tissue; Whether dental pulp tissue can establish effective blood circulation through the apical foramen remains a great challenge.

Biopolymeric In Situ Hydrogels for Tissue Engineering and Bioimaging Applications

BACKGROUND: Biopolymeric in situ hydrogels play a crucial role in the regenerative repair and replacement of infected or injured tissue. They possess excellent biodegradability and biocompatibility in the biological system, however only a few biopolymeric in situ hydrogels have been approved clinically. Researchers have been investigating new advancements and designs to restore tissue functions and structure, and these studies involve a composite of biometrics, cells and a combination of factors that can repair or regenerate damaged tissue. METHODS: Injectable hydrogels, cross-linking mechanisms, bioactive materials for injectable hydrogels, clinically applied injectable biopolymeric hydrogels and the bioimaging applications of hydrogels were reviewed. RESULTS: This article reviews the different types of biopolymeric injectable hydrogels, their gelation mechanisms, tissue engineering, clinical applications and their various in situ imaging techniques. CONCLUSION: The applications of bioactive injectable hydrogels and their bioimaging are a promising area in tissue engineering and regenerative medicine. There is a high demand for injectable hydrogels for in situ imaging.

Research progress of injected hydrogel in the treatment of myocardial infarction / 国际生物医学工程杂志

Due to myocardial necrosis and fibrous scar formation after acute myocardial infarction,patient's ventricular remodeling and cardiac function is reduced,which will cause serious impact on the long-term prognosis of patients with myocardial infarction.As new biological substitute materials,the hydrogels are superior in hydrophilicity and biocompatibility and have been widely used in the research of myocardial infarction's treatment.The hydrogels can be used alone or served as a promising cell/drug delivery vehicle.Many reports show that intramyocardial injection of hydrogels attached with stem cells and drugs can prevent left ventricle (LV) wall thinning,increase arteriole and capillary density,raise restoration ratio of implanted stem cells,facilitate controlled release of bioactive drugs,limit post-ischemic remodeling and preserve LV function in a certain extent.This article reviews injectable hydrogels research progress in the treatment of myocardial infarction.