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

An ideal meniscus substitute should possess a remarkable resemblance to the native meniscus, which includes structural integrity, biocompatibility, mechanical strength, and durability. Understanding the meniscus anatomy, microarchitecture, and biomechanical properties of the meniscus can help in developing innovative designs, and advancements for addressing meniscus injuries and replacement. Emphasis is made on the promising application of decellularized extracellular matrix (dECM) as a source material for bioink in meniscus 3D printing. This paper examines the criteria required for dECM bioink, including immunogenicity, ECM composition, printability, biocompatibility, biomechanical properties, types of cross-linkers, and their potential applications. By comprehensively addressing these factors, researchers can optimize dECM bioink for 3D printing and develop meniscus substitutes that closely mimic the native meniscus. In conclusion, this review highlights the most promising approaches for 3D printing the meniscus, drawing on the insights gained from the analysis of meniscus anatomy, biomechanics, and dECM bioink characteristics.

The study explores the potential of zeolites as carriers for controlled trimethoprim (TMP) release. Zeolites of types X and Y were ion-exchanged with lanthanum (La³⁺) and cerium (Ce³⁺) ions and characterized to evaluate their efficacy in TMP sorption and delivery. Although type X zeolites were ineffective, type Y zeolites demonstrated significant TMP retention, with CeY adsorbing 0.95 mg (58%) and LaY adsorbing 0.78 mg (49%) of TMP per gram. Characterization techniques, including nitrogen adsorption/desorption, FT-IR, EDS, and SEM, confirmed TMP adsorption within the zeolite structure without altering its morphology. TMP release studies conducted in simulated body fluid (pH 7.4) and acidic conditions (pH 5) revealed sustained release profiles, with CeY outperforming LaY in both environments. The results highlight the potential of CeY and LaY zeolites as carriers for TMP, enabling controlled drug delivery while minimizing burst release. These findings offer a promising approach to improving antibiotic treatment and combating antibiotic resistance development.

This study aims to examine the effect of the chitosan/polyethylene oxide (Cs/PEO) scaffold on sciatic nerve regeneration and neural tissue angiogenesis in adult male rats. Thirty two rats were divided into normal, control, sham and Cs/PEO groups. In the control, sham and Cs/PEO groups, the sciatic nerve was severed in the middle region of the thigh, and epineuria was sutured. After 8 weeks, the functional recoveries, the nerve conduction velocity (NCV), the nerve fiber number, the largest nerve fiber area (LNFA), the largest axon area (LAA) and the number of blood vessels were evaluated. Nerve fiber numbers showed a statistically significant increase in the Cs/PEO, control and sham relative to the normal group. The mean size of the LAA and blood vessels indicated a significant increase in the Cs/PEO group in comparison with the others and the normal group, respectively. The study demonstrated that nerve regeneration with epineural sutures and Cs/PEO could prevent fatal neuron changes and promote angiogenesis following sciatic nerve injury particularly in the first 2 weeks, which rescue some neurons in this initial vital time of injury. However, the Cs/PEO scaffold alone may not be sufficiently effective in sciatic nerve regeneration over a long time period.

The degree of bone ingrowth in the porous implant is influenced by design parameters (pore size, thickness of porous buttresses, and core material). The purpose of this numerical study was to assess how the variation of the implant's design parameters influences bone ingrowth into a porous hip stem, as proposed by the authors in a previous study. Eight macromodels of the implant-bone structure were developed based on the design of experiment approach (full factorial design with three parameters and two levels each). These finite element (FE) macromodels were solved in ANSYS under normal walking and stair climbing loadings and physiological boundary conditions. A 3D submodel corresponding to each macromodel was considered for bone ingrowth simulation. Total displacement at the cut boundaries of the macromodels was mapped to submodels. Bone ingrowth was predicted by integrating a phenomenological mechanoregulatory algorithm with FE analysis of the submodels. The ANOVA and regression analysis were performed between design parameters and responses (bone ingrowth and elastic modulus of newly formed tissues). Within the first month following surgery, the study predicted a significant amount of bone ingrowth (32%–72%) even in proximal regions and a smaller amount of fibrous tissue ingrowth (0.5%–3.5%) in all submodels. At equilibrium iteration, the average Young's modulus of the newly formed bone tissue layer ranged from 380 to 1200 MPa, considering all the submodels. The higher pore size, FGM core and half-porous buttresses provide better bone ingrowth that results in a higher elastic modulus of the newly developed tissue inside the pores of the hip stem. This bone ingrowth is expected to potentially improve long-term fixation and stability of the hip stem, reducing the risk of implant loosening.

Ureteral stents are flexible implants commonly made from polyurethane and silicone. Some ureteral stents used in Indonesia experience damage upon removal, even when patients arrive on time for stent removal. This study was conducted to investigate the effect of the mechanical properties of ureteral stent materials on their service life. The tests conducted included tensile testing and material composition analysis using two different Fourier Transform Infrared Spectroscopy (FTIR) devices. In addition, to determine the presence of material mixtures, composition testing was also performed using SEM/EDX. Five samples of ureteral stent products commonly available in Indonesia were selected for this study: two samples with a service life of 2 months, one sample with a 6-month service life, and two samples with a 12-month service life. Analysis of Variance (ANOVA) testing was carried out to confirm correlations between the investigated variables. The results showed that there was no significant effect of the material's mechanical properties, either tensile strength or elastic modulus, on the service life of the ureteral stent. The results showed no statistically significant correlation (p > 0.05) between tensile strength or elastic modulus and service life. Instead, material choice should match intended duration: polyurethane for short-term (< 6 months) and silicone for long-term (> 6 months). Recommended minimum tensile strength is 11.81 MPa for silicone and 9.11 MPa for polyurethane. These results provide practical guidance for designing ureteral stents based on service life rather than mechanical properties.

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.