Biomaterials Translational最新文献

Due to the limited effects of current treatments on brain repair and regeneration, stroke continues to be the predominant cause of death and long-term disability on a global scale. In recent years, hydrogel-based biomaterials combined with stem cells and extracellular vesicles have emerged as promising new treatments to improve brain regeneration after stroke. However, the clinical translation of hydrogel-based biomaterials for the treatment of brain injury is still far from satisfactory. In this review, we first summarise the present status of stroke-related clinical treatments and the advantages provided by hydrogel-based materials in combination with stem cells and extracellular vesicles in preclinical studies. We then focus on the possible causes of the gap between preclinical studies and clinical translation of hydrogel-based biomaterials from the perspective of biocompatibility and safety, the choices of preclinical models, the lack of clinical noninvasive imaging methods, standardisation and quality control, manufacturing scalability, and regulatory compliance. With the progress in the abovementioned areas, we believe that the clinical translation of hydrogel-based biomaterials will greatly improve brain regeneration after stroke and that this improvement will be realised by the general public in the near future.

Hydrogels are an advanced class of biomaterials with similar properties to living tissues. Several polymers have been investigated for the preparation of hydrogels that closely mimic the structural and functional properties of the extracellular matrix. Proteins with easily modifiable functional groups, specific biochemical effects, and sensitivity to external stimuli are promising candidates for the preparation of hydrogels for biomedical applications. Among them, natural milk proteins, due to their high yield, high-quality control, low cost, and certain biological properties, have become a major focus of research. However, there is a lack of comprehensive reviews focusing specifically on milk protein-based hydrogels. Here, we synthesise the developments in milk protein-based hydrogels, focusing primarily on hydrogels derived from milk proteins. We described the methods used to construct milk protein-based hydrogels and summarised advances in representative applications of milk protein-based hydrogels, such as controlled delivery and regenerative medicine, as well as related preclinical animal experiments and an exploratory clinical pilot study. Finally, we discuss the prospects of milk protein-based hydrogels in biomedical applications. We anticipate that this review will serve as a theoretical basis for the biomedical use of milk proteins and provide a reference for their continued development.

The field of orthopaedic implants has experienced rapid growth in recent decades, evolving from a few obscure examples to become one of the most vibrant domains within regenerative medicine. Polyetheretherketone (PEEK) stands out as a formidable competitor in this field due to its exceptional biocompatibility and appropriate mechanical strength. However, the clinical application of PEEK is limited by its inherent biological inertness. Therefore, numerous studies have focused on overcoming the bio-inert issue of PEEK using surface activation techniques. It is necessary to delve into the intricate effects of these modifications and their corresponding methods. In this review, we provide a comprehensive summary of contemporary research on surface modification for enhancing osseointegration of PEEK implants, categorising them into four parts based on their modification methods and techniques used: (1) physical treatment, (2) wet chemical methods, (3) combination of physical and chemical treatments, and (4) bioactive coating. Finally, we outline the challenges and unmet needs that must be addressed by future designs of PEEK surfaces. Overall, altering the surface morphology and/or surface group of PEEK to obtain a rough, porous, hydrophilic, and bioactive surface, or incorporating bioactive agents/coatings with bone-forming abilities onto the surface of PEEK has shown great potential for promoting osseointegration, which can serve as a solid foundation for subsequent clinical translation.

Spinal cord injury (SCI) is recognised as a debilitating condition that often leads to considerable disability and functional limitations. Exosomes, which can be derived from various cell types including bone marrow mesenchymal stem cells, adipose-derived stem cells, dental pulp stem cells, and macrophages, play a pivotal role in the post-SCI landscape. Collectively, it has been observed that these exosomes can modulate the immune response following SCI, regulate the inflammatory environment, inhibit secondary tissue damage, and support neuronal survival and axonal regrowth. However, it is noted that exosomes from different sources exhibit distinct characteristics. Therefore, it is deemed essential to gain a comprehensive understanding of the current knowledge and research directions regarding exosomes in SCI to foster the development of effective therapeutic interventions. In this bibliometric analysis, we conducted to search retrieve pertinent articles from the Web of Science Core Collection and identify pivotal publications, authors, institutions, countries, and keywords that have contributed significantly to the field. This bibliometric analysis offers a thorough examination of the present knowledge landscape and prevailing research trends pertaining to exosomes in the context of SCI. It acts as a valuable asset, catering not only to researchers but also to clinicians and policymakers engaged in research on SCI and therapeutic advancement. Ultimately, this knowledge mapping can advance our understanding of exosome biology and pave the way for innovative interventions to improve outcomes for individuals affected by SCI.

Fused filament fabrication (FFF) in additive manufacturing has emerged as a potential technology in the development of tissue engineering scaffolds of precise, complex geometries. The choice of material and process parameters is significant in determining their properties, such as mechanical strength. Polymer-ceramic composites with exceptional bioactivity have the potential for FFF applications in fabricating scaffolds. In this study, polylactic acid (PLA) composite scaffolds reinforced with silicon nitride (Si₃N₄) particles in various weight ratios (97:03, 95:05, and 93:07 weight%) were developed using FFF technology. Taguchi's orthogonal array and grey relational analysis were employed to optimize three parameters (polymer-reinforcement ratio, infill density, and layer thickness) to analyze mechanical strength - through tensile, compressive, flexural, and impact tests - surface morphology using scanning electron microscopy, and biocompatibility through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT assay). The optimal formulation of 95:05 wt.%, 0.17 mm layer height, and 100% infill density demonstrated superior mechanical properties with a tensile strength of 47.52 MPa, flexural strength of 67.3 MPa, compressive strength of 71.57 MPa, and impact strength of 2.63 kJ/m². Analysis of variance revealed layer thickness as the most influential factor (41.7%) impacting mechanical properties, followed by PLA: Si₃N₄ ratio and infill density. MTT assay and immunofluorescent staining analysis revealed that the optimal formulations enhanced cell viability and proliferation compared to controls.

Skeletal injuries and disorders are major causes of physical disability worldwide, posing an intractable clinical challenge. Within the field of regenerative medicine, researchers are continuously developing new therapeutic strategies to promote bone regeneration. Small molecules, defined as bioactive compounds with a molecular weight of <1,000 Da, have emerged as promising agents capable of precisely regulating intracellular signaling pathways to enhance bone regeneration. Their cost-effectiveness, superior membrane permeability, and minimal immunogenicity have positioned them at the forefront of both fundamental research and clinical applications. In recent years, advancements in artificial intelligence have accelerated the development and screening of small-molecule drugs, broadening their potential therapeutic applications. Furthermore, innovations in dynamic drug delivery systems have advanced the concept of spatial precision, enabling the controlled release of drug doses over time and achieving the spatiotemporal application of small molecules. These systems release specific small molecules in a sequence, synchronizing therapeutic interventions with the dynamic process of bone healing. Spatiotemporal delivery strategies, which effectively replicate the complex and highly ordered processes of bone healing, have the potential to reduce drug side effects and enhance healing efficacy. However, clinical translation remains hindered by insufficient spatiotemporal control and limited pharmacokinetic precision, challenges that this review explores in depth. We systematically examine stage-specific molecular targets of signaling pathways and their corresponding small molecule modulators. In addition, we discuss current approaches to spatiotemporal delivery strategies, such as stimuli-responsive delivery systems. Finally, we explore the status of clinical applications, the challenges encountered, and potential solutions regarding the spatiotemporal release strategy. We hope this review will contribute to the development of future spatiotemporal delivery strategies, ultimately improving outcomes for patients with impaired fracture healing.

The threat of bacterial growth on the skin under the prosthetic liners or sleeves is an important problem, which can cause various serious diseases up to the repeated amputation. One of the promising ways to solve this problem is to use antibacterial materials as a liner/sleeve material. Among others composite based on the silicone polymer with silver particles additive is may be a simple and effective solution, since the silicone is the main material for the prosthetic liners and sleeves and silver demonstrates pronounced antibacterial effect. However, the questions related to the optimal concentration of silver in silicone that results in maximum antibacterial efficiency without harming human skin are still open. In the present work, synthesis of metallic silver powder from a mixture of micro- and nanoparticles was performed and composite samples based on silicone polymer with different silver concentrations were fabricated. The antibacterial properties of fabricated samples were studied using the microdilution method against gram-positive spore-forming bacteria Bacillus subtilis. The cytotoxic effect of the tested samples was evaluated on healthy human fibroblast cell (NAF1nor). Moreover, the effect of adding silver micro- and nanoparticles to silicone on its extensibility and hardness was studied. The results showed that the addition of silver has a noticeable effect on the antibacterial properties of silicone polymer reaching more than 50%. Furthermore, all tested silicone-silver composites were shown to be non-toxic. The presence of silver does not significantly affect the relative elongation of the samples. However, hardness increases with higher silver concentrations. In the final phase, prototypes of the silver-filled silicone prosthetic sleeve were fabricated for utilisation by the patient at the prosthetic-orthopaedic clinic. The testing of the prototype was successfully completed by the patient, thereby demonstrating practical functionality and suitability for clinical use.