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The rapid degradation of magnesium (Mg)-based implants in physiological environment limits its clinical applications, and alloying treatment is an effective way to regulate the degradation rate of Mg-based materials. In the present study, three Mg alloys, including Mg-0.8Ca (denoted as ZQ), Mg-0.8Ca-5Zn-1.5Ag (denoted as ZQ71) and Mg-0.8Ca-5Zn-2.5Ag (denoted as ZQ63), were fabricated by alloying with calcium (Ca), zinc (Zn) and silver (Ag). The results obtained from electrochemical corrosion tests and in vitro degradation evaluation demonstrated that the three Mg alloys exhibited distinct corrosion resistance, and ZQ71 exhibited the lowest degradation rate in vitro among them. After addition of Zn and Ag, the antibacterial potential of Mg alloys was also enhanced. The in vitro cell experiments showed that all the three Mg alloys had good biocompatibility. After implantation in a rat femoral defect, ZQ71 showed significantly higher osteogenic activity and bone substitution rate than ZQ63 and ZQ, due to its higher corrosion resistance as well as the stimulatory effects of the released metallic ions. In addition, the average daily degradation rate of each Mg alloy in vivo was significantly higher than that in vitro, as could be due to the implantation site located in the highly vascularized trabecular region. Importantly, the correlations between the in vitro and in vivo degradation parameters of the Mg alloys were systematically analyzed to find out the potential predictors of the in vivo degradation performance of the materials. The current work not only evaluated the clinical potential of the three biodegradable Mg alloys as bone grafts but also provided a feasible approach for predicting the in vivo degradation behavior of biodegradable materials.

The improved corrosion resistance, osteogenic activity, and antibacterial ability are the key factors for promoting the large-scale clinical application of magnesium (Mg)-based implants. In the present study, a novel nanocomposite coating composed of inner magnesium hydroxide, middle graphene oxide, and outer hydroxyapatite (Mg(OH)2/GO/HA) is constructed on the surface of Mg-0.8Ca–5Zn-1.5Ag by a combined strategy of hydrothermal treatment, electrophoretic deposition, and electrochemical deposition. The results of material characterization and electrochemical corrosion test showed that all the three coatings have high bonding strength, hydrophilicity and corrosion resistance. In vitro studies show that Mg(OH)2 indeed improves the antibacterial activity of the substrate. The next GO and GO/HA coating procedures both promote the osteogenic differentiation of MC3T3-E1 cells and show no harm to the antibacterial activity of Mg(OH)2 coating, but the latter exhibits the best promoting effect. In vivo studies demonstrate that the Mg alloy with the composite coating not only ameliorates osteolysis induced by bacterial invasion but also promotes bone regeneration under both normal and infected conditions. The current study provides a promising surface modification strategy for developing multifunctional Mg-based implants with good corrosion resistance, antibacterial ability and osteogenic activity to enlarge their biomedical applications.

Glioblastoma multiforme (GBM) represents one of the most critical oncological diseases in neurological practice, being considered highly aggressive with a dismal prognosis. At a worldwide level, new therapeutic methods are continuously being researched. Magnetic hyperthermia (MHT) has been investigated for more than 30 years as a solution used as a single therapy or combined with others for glioma tumor assessment in preclinical and clinical studies. It is based on magnetic nanoparticles (MNPs) that are injected into the tumor, and, under the effect of an external alternating magnetic field, they produce heat with temperatures higher than 42 °C, which determines cancer cell death. It is well known that iron oxide nanoparticles have received FDA approval for anemia treatment and to be used as contrast substances in the medical imagining domain. Today, energetic, efficient MNPs are developed that are especially dedicated to MHT treatments. In this review, the subject's importance will be emphasized by specifying the number of patients with cancer worldwide, presenting the main features of GBM, and detailing the physical theory accompanying the MHT treatment. Then, synthesis routes for thermally efficient MNP manufacturing, strategies adopted in practice for increasing MHT heat performance, and significant in vitro and in vivo studies are presented. This review paper also includes combined cancer therapies, the main reasons for using these approaches with MHT, and important clinical studies on human subjects found in the literature. This review ends by describing the most critical challenges associated with MHT and future perspectives. It is concluded that MHT can be successfully and regularly applied as a treatment for GBM if specific improvements are made. [ABSTRACT FROM AUTHOR]

This research aims to identify the prevalence of failure for Birmingham Hip Prosthesis (BHR) in total hip arthroplasty and to analyze its reasons from biomaterials and biofunctional perspectives. We present our current analysis and tests on a series of different BHR-retrieved prostheses after premature failure. Relevant clinical data, such as X-ray investigations and intraoperative images for clinical case studies, were analyzed to better understand all factors involved in BHR prosthesis failure. A detailed analysis of the failures highlighted uneven cement distribution, overloading in certain areas, and void formation in the material. A closer investigation using microscopical techniques revealed the presence of a crack originating from the gap between the cement mantle and human bone. Additionally, scanning electron microscopy analyses were conducted as part of the investigation to examine bone cement morphology in detail and better understand the interactions at the interfaces between implant, cement, and bone. In conclusion, this research emphasizes the importance of surgical technique planning and the cementation procedure in the success rate of BHR prostheses. It also underscores the need to carefully evaluate patient characteristics and bone quality to minimize the risk of BHR prosthesis failure. The cementation procedure seems to be essential for the long-term functionality of the BHR prosthesis. [ABSTRACT FROM AUTHOR]

Treatment of bone defects resulting after tumor surgeries, accidents, or non-unions is an actual problem linked to morbidity and the necessity of a second surgery and often requires a critical healthcare cost. Although the surgical technique has changed in a modern way, the treatment outcome is still influenced by patient age, localization of the bone defect, associated comorbidities, the surgeon approach, and systemic disorders. Three-dimensional magnesium-based scaffolds are considered an important step because they can have precise bone defect geometry, high porosity grade, anatomical pore shape, and mechanical properties close to the human bone. In addition, magnesium has been proven in in vitro and in vivo studies to influence bone regeneration and new blood vessel formation positively. In this review paper, we describe the magnesium alloy's effect on bone regenerative processes, starting with a short description of magnesium's role in the bone healing process, host immune response modulation, and finishing with the primary biological mechanism of magnesium ions in angiogenesis and osteogenesis by presenting a detailed analysis based on a literature review. A strategy that must be followed when a patient-adapted scaffold dedicated to bone tissue engineering is proposed and the main fabrication technologies are combined, in some cases with artificial intelligence for Mg alloy scaffolds, are presented with examples. We emphasized the microstructure, mechanical properties, corrosion behavior, and biocompatibility of each study and made a basis for the researchers who want to start to apply the regenerative potential of magnesium-based scaffolds in clinical practice. Challenges, future directions, and special potential clinical applications such as osteosarcoma and persistent infection treatment are present at the end of our review paper. [ABSTRACT FROM AUTHOR]