Journal of biomedical materials research. Part B, Applied biomaterials最新文献

Significant anti-inflammatory qualities are exhibited by nanoparticles, which are essential for efficient burn wound healing. Numerous methods based on nanoparticles have proven successful in reducing excessive inflammation, avoiding infection, and encouraging tissue regeneration. In this study, we describe the creation of zinc nanoparticles for the treatment of burn wounds using an aqueous extract from Pulsatilla chinensis leaves. Several analytical techniques, including XRD, UV–Vis, FE-SEM, and FT-IR, were used to characterize the final biomaterial. ZnNPs@Pulsatilla chinensis was used to treat 75 Wistar rats' induced burn injuries. For 30 days, the animals received basal, tetracycline 3%, ZnNPs@Pulsatilla chinensis 1%, and Pulsatilla chinensis leaf aqueous extract 1% therapy. The reduction in burn wound area as well as molecular and histological features were used to assess the effectiveness of the treatment. One group served as the control group. All groups treated with ZnNPs@Pulsatilla chinensis had mean wound surfaces that were greater than those of the control group. VEGF, PDGF, bFGF, and EGF were all elevated by ZnNPs@Pulsatilla chinensis ointment. When combined, these findings provide credence to the therapeutic application of ZnNPs@Pulsatilla chinensis as a strong ointment that might be suggested for the healing of burn wounds.

This study introduces a comparative in vivo evaluation of four synthetic biomaterials with distinct resorption profiles—double-setting alpha-tricalcium phosphate (α-TCPdp), α-TCPdp combined with a lactic-co-glycolic acid and poly(isoprene) copolymer (PLGA/PI), and two 3D-printed polymers, acrylonitrile butadiene styrene (ABS) and polyamide (PA)—for reconstruction of critical-sized mandibular defects in rabbits. Twenty animals were divided into four groups (n = 10 defects each) and evaluated at 30, 60, and 120 days post-implantation through clinical, radiographic, histopathological, and scanning electron microscopy analyses. All implants exhibited excellent biocompatibility, osseointegration, and absence of adverse tissue reactions. ABS and PA promoted significantly greater early bone neoformation compared to α-TCP-based cements, whereas α-TCPdp and α-TCPdp + PLGA/PI underwent gradual bone replacement via surface degradation and creeping substitution. The addition of PLGA/PI reduced the inflammatory response without compromising osteoconductivity. SEM analysis, enhanced by an adapted decalcification protocol, confirmed continuous bone ingrowth and intimate bone–implant contact. This work provides the first direct comparison of α-TCPdp and polymer-based implants in a mandibular critical defect model, highlighting the potential of both absorbable and non-absorbable biomaterials for customized craniofacial reconstruction.

This study explores the potential of 3D-printed carbon fiber-reinforced thermoplastic composites, specifically Nylon and PEEK, as advanced materials for medical implants. Fabricated using fused filament fabrication (FFF), these implants were evaluated against conventional Ti-6AL-4V titanium alloy counterparts through a combination of experimental analysis and finite element method (FEM) simulations. The novel designs of discontinuous carbon fiber-PEEK and continuous carbon fiber-Nylon composites exhibited enhanced performance, reducing screw pull-out force by nearly 50% relative to Ti-6AL-4V. Furthermore, the thermoplastic composites demonstrated significantly higher bio-elastic coupling strain energy density (SED), indicating superior capacity to promote bone healing and callus formation. A comprehensive multi-criteria evaluation—including metrics on screw loosening, bone remodeling, and resorption—revealed that the 3D-printed composites outperformed titanium by 33%–65%. These results provide design guidelines for FFF 3D-printed composite implants, offering considerable promise as customizable and effective alternatives to conventional metal implants.

Failures in oral implant installation may be associated with elevated concentrations of matrix metalloproteinases (MMPs). The overexpression of these enzymes leads to extensive extracellular matrix degradation, delaying or impairing tissue repair. Moreover, their endogenous inhibitors, tissue inhibitors of metalloproteinases (TIMPs), are often insufficient to counteract pathologically elevated MMP levels. To address this, various MMP-regulating strategies have been explored, including the use of flavonoids such as naringenin (NA), a citrus-derived compound with promising anti-inflammatory effects and MMP downregulation. Additionally, surface modifications of titanium (Ti) implants can enhance tissue response and improve osseointegration. This study aimed to characterize and evaluate the effects of Ti surface modification through alkali treatment and NA-laden gelatin methacryloyl (GelMA) coating on osteoblast (Ob) functions related to peri-implant repair in vitro. Ti discs were alkalinized using 5 M sodium hydroxide (NaOH) at 60°C for 24 h. GelMA hydrogel (15% w/v) containing 0% (control) or 1% NA (w/w) was prepared and applied as a coating. The coatings were characterized for morphology, swelling, degradation, and NA release profile. SAOS-2 osteoblasts (HTB-85) were then cultured on the coated discs, and cell adhesion, viability, and synthesis of MMP-2, MMP-9, TIMP-1, and TIMP-2 were assessed. Data were analyzed by one- or two-way ANOVA and Student's t-test/post hoc tests (α = 0.05). Scanning electron microscopy confirmed successful coating, with the GelMA+NA 1% group showing a more uniform and porous surface compared to GelMA alone. Both formulations displayed similar swelling capacity and degradation profiles over 21 days (p > 0.05). NA release was sustained for 14 days, peaking at 15 h. Cell viability and adhesion were comparable between groups (p > 0.05). Osteoblasts cultured on GelMA and exposed to the inflammatory stimulus tumor necrosis factor-alpha (TNF-α) showed increased synthesis of MMP-2, MMP-9, TIMP-1, and TIMP-2. However, cells cultured on GelMA+NA 1% exhibited significantly reduced MMP-2 and MMP-9 levels compared to GelMA under TNF-α stimulation (p < 0.05), with no significant changes in TIMP-1 or TIMP-2. In summary, Ti surface modification through alkali treatment followed by GelMA/NA coating was cytocompatible, showed controlled degradability, sustained NA release, and downregulated MMP synthesis in osteoblasts. These results suggest its potential as a promising strategy to modulate MMPs, which may help mitigate excessive matrix degradation and favor peri-implant tissue repair.

Bone tissue exhibits inherent bioelectrical properties, and electrical stimulation (ES) has been demonstrated to effectively accelerate bone healing. However, insufficient attention has been devoted to investigating biocomposite materials that synergize with electrostimulation for bone defect repair. In this study, a composite of strontium-doped hydroxyapatite and chitosan (Sr-HA@CS) was synthesized and demonstrated to promote bone regeneration. Under combined ES, the Sr-HA@CS hydrogel not only exhibited excellent injectability, biocompatibility, and osteoinductivity, but also significantly upregulated osteogenesis-related genes and accelerated the osteogenic process, as revealed by RNA sequencing analysis. This synergistic effect further promoted intracellular calcium enrichment and enhanced bone regeneration in vivo. Therefore, the development of the Sr-HA@CS composite combined with ES therapy holds promise for accelerating bone repair and represents an important area of research.

This study investigates the structural, morphological, hydrodynamic, colloidal stability, anticancer, antibacterial, antioxidant, and hemolytic properties of Cu and Mn doped ZnS nanosheets (NSs). XRD examination indicated that the produced NSs exhibit high purity with a cubic structure. The average crystallite size was determined to be 1.66 nm for ZCMn1, 1.60 nm for ZCMn2, 1.26 nm for ZCMn3, and 1.39 nm for ZCMn4 NSs (ZnS = ZCMn1; Zn_0.98Cu_0.02S = ZCMn2; Zn_0.97Mn_0.01Cu_0.02S = ZCMn3; Zn_0.96Mn_0.02Cu_0.02S = ZCMn4). TEM analysis showed that the synthesized NSs exhibit a crumpled nanosheet morphology with agglomerated particles. The ZCMn4 NSs displayed the smallest hydrodynamic size and the best colloidal stability. The ZCMn4 NSs also demonstrated superior antibacterial efficacy, with zones of inhibition (ZOI) measuring 14mm, 14 mm, 17 mm, 16 mm, and 13 mm for S. aureus, E. faecalis, P. aeruginosa, E. coli, and C. albicans, respectively. Antioxidant and hemolytic activities were also evaluated, further highlighting the multifunctionality of the synthesized nanomaterials. Notably, the ZCMn4 NSs exhibited minimal hemolytic activity, with a lysis rate of only 0.33% at a dosage of 500 μg/mL. The doped and dual-doped ZnS NSs exhibited strong and selective cytotoxic effects against melanoma cells while sparing normal melanocytes. Furthermore, a TUNEL assay was performed to confirm that the reduction in cell viability resulted from apoptotic cell death. These findings underscore the potential of Mn and Cu-doped ZnS nanosheets as promising therapeutic nanomaterials for cancer treatment, drug delivery, MRI, and other biological applications.

Polyanhydride particle-based vaccines overcome several limitations of current vaccines owing to their ability to encapsulate different types of antigenic payloads, provide tunable release kinetics of payloads, and induce protective immunity against multiple respiratory infections. In this work, two particle synthesis methods were compared by analyzing the structure and antigenicity of released proteins from particles made by these methods. Flash nanoprecipitation is a lab-scale method to synthesize protein-loaded particles. Spray drying is a scalable method that allows for the production of protein-loaded particles. The polyanhydride copolymer used for both synthesis methods was composed of a 20:80 M ratio of 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane and 1,6-bis(p-carboxyphenoxy)hexane. The three proteins used in this work are bovine serum albumin (a model, globular protein), and SARS-CoV-2 spike and bovine RSV post-F protein (both clinically relevant proteins). The release kinetics of the encapsulated proteins were studied, and the structure of the released proteins was analyzed using gel electrophoresis and fluorescence spectroscopy. The antigenicity of the released spike and post-F was estimated based on the binding of positive mouse sera from previously inoculated mice. Our results indicate that both flash nanoprecipitation and spray drying resulted in particle formulations that provided a burst release of protein followed by a sustained period of release. The primary and tertiary structures and the antigenicity of the released proteins were maintained consistently across both methods. Altogether, these studies indicate that spray drying can be used to generate particles that stabilize encapsulated antigens and for at-scale particle synthesis in the future.