Journal of biomedical materials research. Part A最新文献

Bioprosthetic heart valves (BHV) fabricated from heterograft tissue such as glutaraldehyde fixed bovine pericardium (BP), while less thrombogenic than mechanical valve prostheses, nevertheless demonstrate a significant risk for platelet initiated thromboembolic events. We showed previously using in vitro and in vivo model systems that pyridoxamine (PYR), a Vitamin B6 vitamer, used as a BP pretreatment, mitigated advanced glycation end product (AGE) formation. PYR is also known to inhibit platelet aggregation. In the present studies, both BP and collagen-coated polyvinyl chloride tubing (PVC-collagen) were fixed with glutaraldehyde and were either untreated or pretreated with PYR; both the PYR content and binding stability were quantitated. PYR-BP binding stability was demonstrated in vitro over 28 days. Methylglyoxal (MGO), a representative AGE, was used to modify BP and PVC-collagen for use in platelet activation studies in an ex vivo flow loop with human whole blood. MGO modified collagen-coated PVC demonstrated both increased platelet activation, per P-selectin expression, and increased platelet adhesion compared to non-MGO modified samples. PYR pretreatment of either collagen-coated PVC or BP, with or without MGO exposure, significantly mitigated these effects. In conclusion, BP and collagen surfaces are susceptible to platelet activation and adhesion that is effectively mitigated by vitamin B6.

Traditional 2D cell cultures and animal models have served as the foundations of biomedical research. These have significant limitations in modeling human physiology and predicting outcomes of therapy. Recent developments in 3D organoids and organ-on-chip technologies have shifted the field by enabling human relevant dynamic and scalable platforms for disease modeling and drug discovery and toxicity evaluation. Organoids derived from either stem cells or patient samples accurately recreate complex cellular structure and function found in human organs. The combination of organoids with organ-on-chip systems, or micro-engineered devices that closely simulate the interactions between distinct organ types including tissue to tissue as well as fluids and mechanical forces, allows researchers to continually monitor and manipulate the immediate environment of cells. The focus of this study will be on the underlying technologies for the manufacture and use of these systems as well as the main applications of these systems. Future research will include the development of multi-organ chips, artificial intelligence (AI), and biosensors. This study also illustrates how organoids and organ-on-chip technologies will enable the modeling and mimicking of common neurological, liver, gut, heart, cancer, and infectious diseases, as well as their application for high-throughput drug screening and nanotoxicology applications which could potentially help to lessen our reliance on animals for preclinical drug testing. The combined use of CRISPR gene editing, multi-omics profiling, and machine-learning technology is accelerating the transition to personalized medicine. In spite of issues surrounding the standards associated with the use of organoid and organ-on-chip technology, ethical issues, and the magnitude of scalability, there continues to be ongoing technical advances and government support for this quickly developing technology. Organoids and organ-on-chip technologies represent a fundamental shift in the practice of biomedical research and may allow us to more closely and accurately simulate authentic human physiology while providing more efficient and safer platform for drug discovery to be conducted.

Wound dressings incorporating plant extracts are attracting considerable attention due to their ability to deliver bioactive molecules that promote wound healing. This study reports on the development of self-supporting hydrogel sheets loaded with natural Aloe vera (AV) juice and the evaluation of their cytocompatibility and AV release profile for wound dressing applications. Hydrogels composed of poly(vinyl alcohol) (PVA) and polyvinylpyrrolidone (PVP) were first crosslinked by electron beam (EB) irradiation to systematically investigate the effect of polymer compositions on the swelling and rehydration properties of hydrogels. The latter was harnessed as a process for incorporating AV juice into the dried hydrogels. While all compositions absorbed water, only hydrogels containing ≥ 70% (w/w) PVP could rehydrate beyond their original dimensions, a phenomenon attributed to larger surface pores observed in these formulations. The optimal 30PVA/70PVP composition was selected for AV loading via rehydration, followed by EB decontamination to ensure sterility. The resulting AV-loaded hydrogels were cytocompatible with L929 and human dermal fibroblasts. Furthermore, for the first time, the release of key AV constituents, including ions and the polysaccharide acemannan, was demonstrated as confirmed by mass spectrometry and HPLC analyses, respectively. These results establish a novel, scalable approach for producing decontaminated, crosslinked hydrogel sheets that effectively load and release AV components, offering a promising application-ready wound dressings.

Graphene oxide (GO) nanoparticles hold biomedical promise due to unique properties, but their immunomodulatory effects on phagocytes require evaluation, particularly regarding size- and coating-dependent interactions. Polyethylene glycol (PEG) coatings reduce cytotoxicity, yet long-term impacts of varied coatings remain critical. This study investigated PEGylated GO nanoparticles (P-GO) of two lateral sizes (≈100–300 nm and ≈1–1.5 μm) with linear or branched PEG coatings on THP-1 monocyte viability, apoptosis, metabolism, and wide-spectrum cytokine production. Only the larger branched PEG-coated GO (25 μg/mL) exhibited cytotoxicity after 72 h. Other variants showed no cytotoxicity but modulated THP-1 activity. Larger linear PEG-coated GO induced apoptosis within 24 h. All particles in a concentration of 25 μg/mL were internalized by/adhered to cells, suppressed ROS production, and altered cytokine profiles: TNF-α, MIP-1β, MIP-1α, and G-CSF increased, while HGF and SCGF-β decreased. Larger branched PEG-coated GO suppressed oxidative phosphorylation and glycolysis after 24 h. While a spectrum of effects of PEGylated graphene oxide on THP-1 cell functions was identified, predominantly observed at a dose of 25 μg/mL over a 24 to 72-h exposure period, no clear dependence of P-GO nanoparticle effects on THP-1 cells was observed with respect to PEG coating type (linear vs. branched) or particle size. At 5 μg/mL, P-GO caused minimal functional modulation. Thus, the study underscores the potential of low-concentration P-GO for therapeutic use while cautioning that even non-cytotoxic nanoparticles can profoundly alter immune cell behavior.

In this study, PLGA/CHA/nmZnO antibacterial bone repair scaffolds with different contents of CHA/nmZnO (0%, 15%, 25%, 30%, 35%) were prepared by 3D melt extrusion molding technology. The physicochemical properties, biocompatibility, and in vitro osteogenic performance of the scaffolds were characterized, and a rat model of periodontitis bone defect was constructed to evaluate the osteogenic effect of the scaffolds. Results showed that the scaffolds exhibited interconnected pore structures and appropriate mechanical properties. The contact angles were measured to be between 73.37° ± 1.36° and 85.03° ± 1.45°. The composite scaffolds of the 25%, 30%, and 35% groups had a significant promoting effect on the proliferation and osteogenic differentiation of rat bone marrow mesenchymal stem cells (BMSCs). In the bone defect model, the 30% scaffold showed substantial osteogenic effects at 6 weeks post-implantation, characterized by significant increases in BV/TV, BS/TV, and area of collagen formation, along with decreased trabecular separation. At 12 weeks, the volume fraction and collagen area of new bone surpassed those of Bio-Oss bone graft. Immunohistochemistry indicated that this scaffold effectively inhibited expression of inflammation-related factors TLR2, TLR7, and IL-1β. This study systematically compared the effects of CHA/nmZnO filler content on the performance of PLGA scaffolds, and selected 30% as the optimal ratio, which has both osteogenic induction and immune regulation functions, providing a new design idea for the development of periodontal bone regeneration materials.

Electrochemically prepared self-organized titanium nanotube arrays have emerged as a platform of considerable interest owing to their unique structural and functional attributes, driving advances across energy, photocatalytic, and biomedical fields. Their potential as one-dimensional biomaterials have sparked intensive research focused on their controlled fabrication, properties, surface modification, and integration into advanced biomedical technologies. Herein, zirconium dioxide and multi-walled carbon nanotubes coated titanium nanotube arrays heterostructures were fabricated using different electrolytic combinations (organic electrolyte and water-based electrolyte). Zirconium dioxide coating contributes to enhanced chemical stability and mechanical strength. In parallel, the incorporation of multi-walled carbon nanotubes not only offers increased electrical conductivity and promotes cellular interactions, facilitating osteogenic cell adhesion and proliferation, but also promotes mechanical reinforcement and antibacterial efficacy. Comprehensive physical characterizations, including X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, atomic force microscopy, and Fourier-transform infrared spectroscopy, confirmed successful deposition and morphological uniformity of the duplex coating. In vitro biocompatibility tests using MG-63 osteoblast-like cells demonstrated excellent cytocompatibility, cell adhesion and proliferation. Additionally, water contact angle measurements and nanoscale roughness evaluations revealed considerable surface wettability and superior topography, conducive to osteogenic differentiation. These findings highlight a scalable, chemically stable, and biologically active surface strategy that poses the duplex-coated heterostructure as a next-generation platform for load-bearing implants in bone tissue engineering and regenerative medicine.