Smart Materials in Medicine最新文献

The rapid progress in point-of-care testing (POCT) has become a promising decentralized patient-centered approach for the control of infectious diseases, especially in resource-limited settings. POCT devices should be inexpensive, rapid, simple operation and preferably require no power supply. Here, we developed a simple bacterial sensing platform that can be operated by a smartphone for bacteria identification and antimicrobial susceptibility testing (AST) based on using a polydiacetylene (PDA) arrayed membrane chip. Each PDA array produced a unique color ‘fingerprint’ pattern for each bacteria based on different modes of action of toxins from bacteria on biomimetic lipid bilayers within PDA-lipid assemblies. We show that the PDA-based device can detect viable cells of bacteria as low as 10⁴ ​CFU/mL within 1.5 ​h compared with several days of conventional bacterial identification, with the aid of a smartphone app. The device can also be used for an antimicrobial susceptibility test (AST) for at least two broad-spectrum antimicrobials within 4 ​h and provide identification of antimicrobial susceptibility and resistance, enabling the selection of appropriate therapies. This PDA-based sensing platform provides an alternative way for bacterial detection and could be used as a portable and inexpensive POCT device for the rapid detection of bacterial infection in limited-resource settings.

Additively manufactured lattices based on triply periodic minimal surfaces (TPMS) have attracted significant research interest from the medical industry due to their good mechanical and biomorphic properties. However, most studies have focussed on permanent metallic implants, while very little work has been undertaken on manufacturing biodegradable metal lattices. In this study, the mechanical properties and in vitro corrosion of selective laser melted Fe–35%Mn lattices based on gyroid, diamond and Schwarz primitive unit-cells were comprehensively evaluated to investigate the relationships between lattice type and implant performance. The gyroid-based lattices were the most readily processable scaffold design for controllable porosity and matching the CAD design. Mechanical properties were influenced by lattice geometry and pore volume. The Schwarz lattices were stronger and stiffer than other designs with the 42% porosity scaffold exhibiting the highest combination of strength and ductility, while diamond and gyroid based scaffolds had lower strength and stiffness and were more plastically compliant. The corrosion behaviour was strongly influenced by porosity, and moderately influenced by geometry and geometry-porosity interaction. At 60% porosity, the diamond lattice displayed the highest degradation rate due to an inherently high surface area-to-volume ratio. The biodegradable Fe–35Mn porous scaffolds showed a good cytocompatibility to primary human osteoblasts cells. Additive manufacturing of biodegradable Fe–Mn alloys employing TPMS lattice designs is a viable approach to optimise and customise the mechanical properties and degradation response of resorbable implants toward specific clinical applications for hard tissue orthopaedic repair.

Sorafenib is a first-line drug for liver cancer treatment, but its clinical efficacy is still limited by drawbacks such as drug tolerance, toxic effects, and low bioavailability. Therefore, it is urgent to find efficient ways to synergize sorafenib with other agents and increase its bioavailability in order to enhance its clinical efficacy. Herein, we report the successful development of a carrier-free nanoplatform of an artesunate prodrug to potentiate the efficacy of sorafenib against hepatocellular carcinoma. The artesunate prodrug was synthesized by conjugating artesunate and linoleic acid through a thioketone (TK) bond. This prodrug can self-assemble in an aqueous solution via a one-step precipitation method. Furthermore, the inclusion of sorafenib during the self-assembly process results in a carrier-free artesunate/sorafenib mixed nanomedicine (SA@NPs) with a uniform and stable particle size. In addition, SA@NPs possess ROS-responsive drug-releasing ability by breaking up thioketone bonds under high H₂O₂ levels in tumors. The synergistic anticancer effects of SA@NPs have been demonstrated both in vivo and in vitro. SA@NPs can achieve significantly enhanced synergetic ferroptosis of tumor cells and show potentiated sorafenib efficacy against hepatocellular carcinoma. Moreover, SA@NPs have a tumor inhibition rate of 84.2%, which is 1.63-, 4.22-, and 1.29-fold higher than that in the experimental groups treated with free sorafenib, artesunate, and the simplified combined medication of sorafenib/artesunate, respectively. Overall, this work presents a significant advancement in the clinical chemotherapy of liver cancer and may pave the way for promising developments in the compatibility and clinical combination application of traditional Chinese medicine.

Polyetheretherketone (PEEK) has become a promising material for bone engineering due to its excellent mechanical properties, radiolucency and chemical resistance. However, its inherent bioinertness and lack of osteogenic activity induce a foreign body reaction and fibrous encapsulation, which limits its effectiveness in promoting bone regeneration. Herein, we develop a novel bioactive glass–functionalized PEEK scaffold (ADSP) to accelerate bone regeneration by immunoregulation. Strontium-doped bioactive glass nanoparticles loaded with alendronate (A-SrBG) were coated on the sulfonated PEEK scaffold by the strong adhesion ability of polydopamine. The released bioactive ions from the scaffold can improve the biocompatibilities and osteogenic activity of PEEK. In vitro results showed the ADSP scaffold promoted polarization of the M2 macrophages via the NF-κB pathway to enhance the osteogenic differentiation of rat bone mesenchymal stem cells (rBMSCs). Further, in vivo rat skull drilling model assessment revealed efficient polarization of M2 macrophage and desirable new bone formation. Thus, ADSP scaffold exerted osteoimmunomodulation effect to promote bone regeneration.

Biomedical assays based on optical nanoprobes play an important role in human health. Optical nanoprobes, the nanomaterials with special optical properties, are widely utilized in biomedical assays. Compared with traditional materials, the well-performed optical nanoprobes have certain properties, such as negligible interferences from the background fluorescence and scattering, simple operations and instruments, high sensitivity, and excellent specificity. This paper reviews the mechanisms, materials, and applications of optical nanoprobes. The mechanisms of optical nanoprobes involve fluorescence, phosphorescence, Förster resonance energy transfer (FRET), upconversion luminescence and chemiluminescence. Time-resolved luminescent nanoprobes are usually prepared from rare earth compounds and quantum dots (QDs). Ultralong inorganic phosphorescent nanoprobes are prepared from transition metal compounds, while ultralong organic phosphorescent nanoprobes are usually prepared from π-conjugated compound nanocrystals that exhibit a rigid confinement to suppress the non-radiative transitions and contain heavy atoms to enhance ISC. Time-resolved luminescent nanoprobes and ultralong phosphorescent nanoprobes minimize background interferences by longer luminescence lifetime. Chemiluminescent nanoprobes are usually prepared from compounds that can react with reactive oxygen species (ROS) to form peroxide bonds. Upconversion luminescent nanoprobes are usually prepared from inorganic rare earth fluoride nanocrystals. Chemiluminescent nanoprobes and upconversion luminescent nanoprobes can avoid background interferences because excitation light of shorter wavelength is not needed. FRET nanoprobes and luminescence quenching nanoprobes are prepared from a donor and an acceptor that can be linked or delinked by the analyte. Optical nanoprobes are applied in both in vitro diagnoses and in vivo imaging. The in vitro applications of optical nanoprobes include the determination of varieties of biomacromolecules and small molecules, while the in vivo imaging involves the diagnoses of inflammation and tumors.

Cellular traction forces (CTFs) are generated by adherent cells and involved in regulating migration, morphology, and homeostasis. Accurate measurement of CTFs is crucial for understanding fundamental biological processes such as morphogenesis, angiogenesis, and wound healing. However, directly measuring CTFs, which typically range in the nanonewton scale, is challenging. Cellular traction force microscopy (TFM) has been developed to quantify CTFs, but detailed operational procedures and complex data analysis limit its applicability. In this study, hydrogels embedded with fluo-spheres serve as the substrate for TFM measurement under a detailed TFM protocol. Additionally, we designed a user-friendly program for easy parameter setting. An open-source program called Python Fourier transform traction cytometry (pyFTTC) is introduced for data analysis, utilizing particle image velocimetry (PIV) to calculate the traction force from a batch of images. Cross-correlation based PIV and L2-regularized FTTC are applied to all images for data analysis. This article provides a straightforward protocol for quantifying CTFs in standard laboratories, facilitating both cell biology studies and biomaterials development.

Glioma is the most common malignant tumor of the central nervous system. Drug-assisted chemotherapy is an important adjuvant treatment post-surgery, but currently, effective chemotherapy drugs for glioma are lacking. Expediting new and effective chemotherapy drugs is a persistent problem that needs to be solved. In this study, a tetramic acid derivative, trichobotrysin B, was extracted from the ascidian-derived fungus Trichobotrys effusa 4729 (denoted ADF_Te4729). There is significant cytotoxicity of trichobotrysin B against glioma proliferation, which triggers apoptosis and cell cycle arrest. Furthermore, studies have found that trichobotrysin B inhibits glioma proliferation in a manner closely related to IL-6-mediated STAT3 phosphorylation and JAK2 activation. In conclusion, this study demonstrates that the small-molecule compound trichobotrysin B inhibits glioma proliferation and induces apoptosis through the IL-6-mediated STAT3/JAK2 signaling pathway, suggesting that trichobotrysin B has potential antiglioma efficiency and provides a new way to explore new small-molecule drugs with anticancer effects.

Excessive local movement and inflammation are common problems in the process of wound repair, which lead to failure of later repair. In order to solve this problem, inspired by the octopus sucker structure, we successfully developed a photocrosslinked hydrogel that can adsorb skin surface fascia. In addition, extracellular vesicles from human bone marrow mesenchymal stem cells are encapsulated in the octopus like sucker structure. The morphology and structure of extracellular vesicles in bone marrow mesenchymal stem cells were detected by scanning electron microscopy and particle size analysis. Through iTRAQ, we tested the expression of angiogenesis related proteins contained in extracellular vesicles. Design small interfering RNA to verify its impact on angiogenic related genes and proteins. Macrophage polarization was detected by immunofluorescence. The expression of new blood vessels was detected by constructing a skin defect model and injecting microfil contrast agent into the heart. When the sucker is firmly adsorbed on the damaged wound, the sucker will slowly degrade. Using its delivery system, it is observed that the extracellular vesicles are released in the wound. Through iTRAQ, it was found that the angiogenesis regulator (angiopoietin-like 4, angiopoietin-like 3 and aminopeptidase N) released in the extracellular vesicles regulates collagen deposition, angiogenesis, and inhibits macrophage aggregation. In addition, the slowly released extracellular vesicles will further inhibit the polarization of proinflammatory macrophages. This biological behavior can provide an adaptive microenvironment for skin regeneration at an early stage. This new bionic octopus sucker structure gel creates a good microenvironment for wound repair and shortens the wound healing time. Therefore, this hydrogel inspired by the octopus sucker structure may provide a good strategy and commercial value for promoting wound repair treatment in clinical practice.

Three-dimensional (3D) printing is emerging as an innovative technology, which is widely used in cardiovascular disease at bench and bedside. During the last decade, with the development of 3D printing industry, many 3D printed models have been used in clinic, because it can provide the advantage of haptic feedback, direct manipulation, and enhanced doctors’ understanding of cardiovascular anatomy and underlying pathologies. In addition to the preparation of 3D printed models, 3D printing technology also shows great application potential in cardiovascular regenerative medicine because it has the advantages of integrating cells, cytokines and materials. Although cardiovascular regenerative medicine application still has a gap between bench and bedside, this gap is gradually narrowing with the development of new materials and new technology of 3D printing recently. In this review, we firstly analyze the characteristics and clinical needs of cardiovascular diseases, and introduce the concept and category of 3D printing technology. Secondly, we summarize the application of 3D printed models, stents, vascular graft, vascular network, and heart organs at bench and bedside. In the end, we discuss the challenges and future perspectives of 3D printing in cardiovascular diseases.

Magnetosurgery, the guidance or actuation of surgical instruments during operations using magnetic forces, has become a global trend in minimally invasive surgeries performed remotely. Despite the promise of the magnetosurgery platform, only select surgeries are compatible with this technology, and issues related to the engineering, materials used, and applications are still not fully understood. In this review, we focus on the engineering and material basis of magnetosurgery in order to summarize and expand existing knowledge to create a versatile platform with multiple surgical applications.