The compressive strength of the original bone tissue was tested, based on the raw human thigh bone,bovine bone,pig bone and goat bone. The four different bone-like apatites were prepared by calcining the raw bones at 800℃ for 8 hours to remove organic components. The comparison of composition and structure of bone-like apatite from different bone sources was carried out with a composition and structure test. The results indicated that the compressive strength of goat bone was similar to that of human thigh bone, reached (135.00±7.84) MPa; Infrared spectrum (IR), X-ray diffraction (XRD) analysis results showed that the bone-like apatite from goat bone was much closer to the structure and phase composition of bone-like apatite of human bones. Inductively Coupled Plasma (ICP) test results showed that the content of trace elements of bone-like apatite from goat bone was closer to that of apatite of human bone. Energy Dispersive Spectrometer (EDS) results showed that the Ca/P value of bone-like apatite from goat bone was also close to that of human bone, ranged to 1.73±0.033. Scanning electron microscopy (SEM) patterns indicated that the macrographs of the apatite from human bone and that of goat bone were much similar to each other. Considering all the results above, it could be concluded that the goat bone-like apatite is much similar to that of human bone. It can be used as a potential natural bioceramic material in terms of material properties.
The presence of thrombus on the surface of blood-contacting biomaterials in clinical practice can significantly impact both the longevity of the biomaterials and the overall survival prognosis of patients. The administration of anticoagulant and antiplatelet medications may heighten the risk of systemic bleeding. Developing biomaterials with anti-thrombogenetic properties and enabling localized anti-thrombosis may offer a solution to these challenges. The development strategies for anti-thrombogenetic biomaterials can be categorized into three main approaches based on the mechanisms of thrombus formation on biomaterial surfaces: altering physical and chemical properties, designing coatings containing or releasing active substances, and promoting endothelialization. However, due to the intricate and interconnected nature of these mechanisms, biomaterials constructed using a single approach may not effectively prevent thrombus formation. The collaborative intervention of various mechanisms can facilitate the development of biomaterials with enhanced blood compatibility.
ObjectiveTo review the research progress and challenges of poly (L-lactic acid) (PLLA) membrane in preventing tendon adhesion. MethodsThe relevant literature at home and abroad in recent years was extensively searched, covering the mechanism of tendon adhesion formation, the adaptation challenge and balancing strategy of PLLA, the physicochemical modification of PLLA anti-adhesion membrane and its application in tendon anti-adhesion. In this paper, the research progress and modification strategies of PLLA membranes were systematically reviewed from the three dimensions of tissue adaptation, mechanical adaptation, and degradation adaptation. ResultsThe three-dimensional adaptation of PLLA membrane is optimized by combining materials (such as hydroxyapatite, polycaprolactone), structural design (multilayer/gradient membrane), and drug loading (anti-inflammatory drug). The balance between anti-adhesion and pro-healing is achieved, the mechanical adaptation significantly improve, and degradation is achieved (targeting the degradation cycle to 2-4 weeks to cover the tendon repair period). ConclusionIn the future, it is necessary to identify the optimal balance point of three-dimensional fitness, unify the evaluation criteria and solve the degradation side effects through the co-design of physicochemical modification and drug loading system to break through the bottleneck of clinical translation.
Objective To develop a biodegradable implantable bone material with compatible mechanics with the bone tissue, providing a new biomaterial for clinical bone repair and regeneration. Methods Silk reinforced polycaprolactone composites (SPC) containing 20%, 40%, and 60% silk were prepared by layer-by-layer assembly and hot-pressing technology. Macroscopic morphology was observed and microstructure were observed by scanning electron microscopy, compressive mechanical properties were detected by compression test, surface wettability was detected by surface contact angle test, degradation of materials was observed after soaking in PBS for 180 days, and proliferation of MC3T3-E1 cells was detected by cell counting kit 8 assay. Six Sprague Dawley rats were subcutaneously implanted with polycaprolactone (PCL) and 20%-SPC, respectively. Masson staining was used to analyze the in vivo degradation behavior and vascularization effect within 180 days. Results The pore defects of the three SPC sections were relatively few. In the range of 20% to 60%, as the silk content increased and the PCL content decreased, the interlayer spacing of silk fabric decreased, and the fibers almost covered the entire cross-section. The compressive modulus and compressive strength of SPC showed an increasing trend, and the compressive modulus of 60%-SPC was slightly lower than that of 40%-SPC. There were significant differences in compressive modulus and compressive strength between the materials (P<0.05). In vitro simulated fluid degradation experiments showed that the mass loss of the three types of SPC after 180 days of degradation was within 5%, with the highest mass loss observed in 60%-SPC. The differences in mass loss between the materials were significant (P<0.05). As the silk content increased, the static water contact angle of each material gradually decreased, and all could promote the proliferation of MC3T3-E1 cells. The subcutaneous degradation experiment in rats showed that 20%-SPC began to degrade at 30 days after implantation, and material degradation and vascularization were significant at 180 days, which was in sharp contrast to PCL. Conclusion SPC has the mechanical and hydrophilic properties that are compatible with bone tissue. It maintains its mechanical strength for a long time in a simulated body fluid environment in vitro, and achieves dynamic synchronization of material degradation, tissue regeneration, and vascularization through the body’s immune regulation mechanism in vivo. It is expected to provide a new type of implant material for clinical bone repair.
The aim of this study was to establish an assessment method for determiningα-Gal(α-1, 3-galactosyle) epitopes contained in animal tissue or animal tissue-derived biological materials with ELISA inhibition assay. Firstly, a 96 well plate was coated with Galα-1, 3-Gal/bovine serum albumin (BSA) as a solid phase antigen and meanwhile, the anti-α-Gal M86 was used to react withα-Gal antigens which contained in the test materials. Then, the residual antibodies (M86) in the supernatant of M86-Gal reaction mixture were measured using ELISA inhibition assay by theα-Gal coating plate. The inhibition curve of the ELISA inhibition assay, the R2=0.999, was well established. Checking using bothα-Gal positive materials (rat liver tissues) andα-Gal negative materials (human placenta tissues) showed a good sensitivity and specificity. Based on the presently established method, theα-Gal expression profile of rat tissues, decellular animal tissue-derived biological materials and porcine dermal before and after decellular treatment were determined. The M86 ELISA inhibition assay method, which can quantitatively determine theα-Gal antigens contained in animal tissues or animal tissue-derived biomaterials, was refined. This M86 specific antibody based-ELISA inhibition assay established in the present study has good sensitivity and specificity, and could be a useful method for determining remnantα-1, 3Gal antigens in animal tissue-derived biomaterials.
The study of viruses traditionally focused on their roles as infectious agents and as tools for understanding cell biology. Recently, however, with the development of structural biology, viruses have now been receiving particular attention in nanotechnology. By chemical methods or by gene modification, viruses have been functionalized as potential building blocks for several applications, such as drug/gene delivery vehicles, advanced vaccine vehicles, and special inorganic or organic nanomaterials. Here we highlight some of the recent progresses in the medical applications of viruses.
Objective To review the osteoimmunomodulatory effects and related mechanisms of inorganic biomaterials in the process of bone repair. Methods A wide range of relevant domestic and foreign literature was reviewed, the characteristics of various inorganic biomaterials in the process of bone repair were summarized, and the osteoimmunomodulatory mechanism in the process of bone repair was discussed. Results Immune cells play a very important role in the dynamic balance of bone tissue. Inorganic biomaterials can directly regulate the immune cells in the body by changing their surface roughness, surface wettability, and other physical and chemical properties, constructing a suitable immune microenvironment, and then realizing dynamic regulation of bone repair. Conclusion Inorganic biomaterials are a class of biomaterials that are widely used in bone repair. Fully understanding the role of inorganic biomaterials in immunomodulation during bone repair will help to design novel bone immunomodulatory scaffolds for bone repair.
Infectious bone defects are usually caused by trauma, surgical infections, or chronic osteomyelitis, and represent a complex and intractable clinical challenge in the field of orthopaedics. Biological scaffolds can achieve synergistic repair of defects by loading antibiotics for controlled release to inhibit bacteria, providing support for cell proliferation and differentiation to promote bone regeneration, and carrying factors or stem cells to enhance vascularization. They possess incomparable advantages over traditional treatment methods in the management of infectious bone defects, and the selection of appropriate biological scaffolds in clinical practice needs to be tailored to the type of defect and the severity of infection. Therefore, this article elaborates on the application and research progress of biological scaffolds in the treatment of infectious bone defects.
Objective To summarize the biomechanical research progress of biomaterials in rotator cuff injury repair and to explore how biomaterials can restore the native histological and mechanical properties of the rotator cuff. Methods The relevant literature at home and abroad was widely reviewed to analyze the biomechanical properties of synthetic biomaterials, naturally derived biomaterials, and tissue grafts in the repair of rotator cuff injuries. ResultsSynthetic biomaterials [such as poly (lactic-co-glycolic acid) and polycaprolactone] can provide initial stable mechanical support due to their adjustable mechanical properties and degradation characteristics, while naturally derived biomaterials (such as collagen and hyaluronic acid) can promote cell adhesion and tissue integration due to their biocompatibility and bioactivity. Tissue grafts exhibit significant clinical utility by providing immediate mechanical stability and promoting tendon-to-bone healing. Three-dimensional bioprinting technology provides new possibilities for personalized repair of rotator cuff injuries by precisely controlling the spatial distribution and mechanical properties of biomaterials. Conclusion Future studies should further optimize the design of bioprinting materials, cell sources, and scaffolds to achieve better mechanical properties and clinical efficacy of biomaterials in the repair of rotator cuff injuries.
Objective To summarize recent research advances of hydrogels for the treatment of osteonecrosis of the femoral head (ONFH). Methods The literature on hydrogels for treatment of ONFH at home and abroad in recent years was extensively reviewed, and the fundamental research and clinical application were summarized and analyzed. Results In the field of fundamental research, functionalized hydrogels (including thermosensitive, oxygen-controlled release, and ion-doped types) demonstrate significant advantages in achieving targeted delivery, controlled release, and microenvironment regulation. Particularly, the development of novel material systems, such as composite scaffold systems, gene-activated hydrogels, and engineered exosomes, has further enhanced treatment precision and biological efficacy. In terms of clinical application, the materials like recombinant human fibroblast growth factor 2 (rhFGF-2) gelatin hydrogels have been validated in multiple trials, showing promising joint preservation rates and bone regeneration capabilities. This opens a promising new clinical pathway for hip-preserving treatment of ONFH. Among these, hydrogel-based multilevel composite scaffolds represent the most promising materials for clinical translation. ConclusionHydrogel systems, by synergistically regulating osteogenesis, angiogenesis, and immunomodulation, and leveraging the unique advantages of functionalized materials in precise drug control and microenvironment regulation, have evolved into advanced platforms for the comprehensive treatment of ONFH. Among them, rhFGF-2 gelatin hydrogels, with their remarkable clinical efficacy, offer a new strategy of significant translational value for hip-preserving therapy.
