Advanced liposome-loaded scaffolds for therapeutic and tissue engineering applications

Liposome is one of the most commonly used drug delivery systems in the world, due to its excellent biocompatibility, satisfactory ability in controlling drug release, and passive targeting capability. However, some drawbacks limit the application of liposomes in clinical, such as problems in transporting, storing, and difficulties in maintaining the drug concentration in the local area. Scaffolds usually are used as implants to supply certain mechanical supporting to the defective area or utilized as diagnosis and imaging methods. But, in general, unmodified scaffolds show limited abilities in promoting tissue regeneration and treating diseases. Therefore, liposome-scaffold composite systems are designed to take advantages of both liposomes’ biocompatibility and scaffolds’ strength to provide a novel system that is more suitable for clinical applications. This review introduces and discusses different types of liposomes and scaffolds, and also the application of liposome-scaffold composite systems in different diseases, such as cancer, diabetes, skin-related diseases, infection and human immunodeficiency virus, and in tissue regeneration like bone, teeth, spinal cord and wound healing.Peer reviewe

A Biomimetic 3D-Self-Forming Approach for Microvascular Scaffolds

The development of science and technology often drew lessons from natural phenomena. Herein, inspired by drying-driven curling of apple peels, hydrogel-based micro-scaled hollow tubules (MHTs) are proposed for biomimicking microvessels, which promote microcirculation and improve the survival of random skin flaps. MHTs with various pipeline structures are fabricated using hydrogel in corresponding shapes, such as Y-branches, anastomosis rings, and triangle loops. Adjustable diameters can be achieved by altering the concentration and cross-linking time of the hydrogel. Based on this rationale, biomimetic microvessels with diameters of 50-500 mu m are cultivated in vitro by coculture of MHTs and human umbilical vein endothelial cells. In vivo studies show their excellent performance to promote microcirculation and improve the survival of random skin flaps. In conclusion, the present work proposes and validifies a biomimetic 3D self-forming method for the fabrication of biomimetic vessels and microvascular scaffolds with high biocompatibility and stability based on hydrogel materials, such as gelatin and hyaluronic acid.Peer reviewe

A Biomimetic 3D-Self-Forming Approach for Microvascular Scaffolds

The development of science and technology often drew lessons from natural phenomena. Herein, inspired by drying-driven curling of apple peels, hydrogel-based micro-scaled hollow tubules (MHTs) are proposed for biomimicking microvessels, which promote microcirculation and improve the survival of random skin flaps. MHTs with various pipeline structures are fabricated using hydrogel in corresponding shapes, such as Y-branches, anastomosis rings, and triangle loops. Adjustable diameters can be achieved by altering the concentration and cross-linking time of the hydrogel. Based on this rationale, biomimetic microvessels with diameters of 50-500 mu m are cultivated in vitro by coculture of MHTs and human umbilical vein endothelial cells. In vivo studies show their excellent performance to promote microcirculation and improve the survival of random skin flaps. In conclusion, the present work proposes and validifies a biomimetic 3D self-forming method for the fabrication of biomimetic vessels and microvascular scaffolds with high biocompatibility and stability based on hydrogel materials, such as gelatin and hyaluronic acid

Hydration-Enhanced Lubricating Electrospun Nanofibrous Membranes Prevent Tissue Adhesion

Lubrication is the key to efficient function of human tissues and has significant impact on the comfort level. However, the construction of a lubricating nanofibrous membrane has not been reported as yet, especially using a one-step surface modification method. Here, bioinspired by the superlubrication mechanism of articular cartilage, we successfully construct hydration-enhanced lubricating nanofibers via one-step in situ grafting of a copolymer synthesized by dopamine methacrylamide (DMA) and 2-methacryloyloxyethyl phosphorylcholine (MPC) onto electrospun polycaprolactone (PCL) nanofibers. The zwitterionic MPC structure provides the nanofiber surface with hydration lubrication behavior. The coefficient of friction (COF) of the lubricating nanofibrous membrane decreases significantly and is approximately 65% less than that of pure PCL nanofibers, which are easily worn out under friction regardless of hydration. The lubricating nanofibers, however, show favorable wear-resistance performance. Besides, they possess a strong antiadhesion ability of fibroblasts compared with pure PCL nanofibers. The cell density decreases approximately 9-fold, and the cell area decreases approximately 12 times on day 7. Furthermore, the in vivo antitendon adhesion data reveals that the lubricating nanofiber group has a significantly lower adhesion score and a better antitissue adhesion. Altogether, our developed hydration-enhanced lubricating nanofibers show promising applications in the biomedical field such as antiadhesive membranes

Colloidal Gold Probe-Based Immunochromatographic Strip Assay for the Rapid Detection of Microbial Transglutaminase in Frozen Surimi

Adding microbial transglutaminase (MTGase) to frozen surimi to enable the surimi to be sold as a higher-grade product at a higher price defrauds surimi product manufacturers and undercuts legitimate industry prices. Therefore, it is important to develop an accurate method of detecting the presence of MTGase in surimi. In this study, an immunochromatographic strip assay with a colloidal gold antibody probe was successfully developed and used to rapidly and qualitatively detect MTGase in surimi samples. The results were obtained in less than 10 min. The limit for the qualitative detection of MTGase using the immunochromatographic strip assay was identified as 1.0 μg/mL. The results of the immunochromatographic strip analysis of frozen surimi samples were verified by comparison with the results of a sandwich enzyme-linked immunosorbent assay. The colloidal gold probe-based immunochromatographic strip assay was thus found to be a rapid, economical, and user friendly method of detecting MTGase in surimi

High-Speed Railways Interference Signal Characteristics and Multiple Remote References Denoising of Magnetotelluric Data in Jizhong Depression, China

In the economically developed Beijing–Tianjin–Hebei region, magnetotelluric data are susceptible to contamination from cultural noise, which can be caused, for example, by urban stray currents, high-speed railways, or high-voltage lines. The multiple remote references method is an effective tool that can be used to suppress interference and improve signal-to-noise ratios. Therefore, this paper first introduces the basic principles of multiple remote references and then takes high-speed railway noise as an example. The characteristics of the time domain and frequency domain of the high-speed railway noise signals are analyzed. Then, we use two remote reference stations (with a single remote reference and multiple remote references) to process the data interfering with the high-speed railway and compare the results. Finally, the multiple remote references method is used to process the data for the entire section. Coupled with the known geological and seismic data, the inversion results well-reflect the deep underground geological structure

Fabrication of Antibacterial and Antiwear Hydroxyapatite Coatings via In Situ Chitosan-Mediated Pulse Electrochemical Deposition

Although bioinert titanium has been widely applied in orthopedics and related fields, its usage is limited by its unsatisfying osteoinductivity, anti-infection capability, and wear-resistance. Osteoinductive apatite coating can be fabricated on a titanium surface by electrochemical methods, but this causes bacterial adhesion and poor wear-resistance. On the basis of pulse electrochemical technology, a wear-resistance and antibacterial osteoinductive coating was fabricated through codeposition of hydroxyapatite (HA) and nano-Ag effectuated by the cohybridization ofchitosan (CS) with Ag⁺ and Ca²⁺. A composite coating formed with uniformly dispersed spherical nanoparticles was obtained at optimized deposition potential, Ag concentration, and apatite concentration. The nanocomposite coating shows excellent bioinductive activity; it promotes preferential growth on the (002) face, and needle-like ordered arrangement of apatite. Due to the mediation of CS hybridization, a compact structure is achieved in the HA/Ag composite coating which significantly enhances the wear-resistance of the coating and reduces the release of Ca²⁺ and Ag⁺. The antibacterial rate of the coating on <i>Escherichia coli</i> and <i>Staphylococcus aureus</i> is up to 99% according to the antibacterial test. In conclusion, a wear-resistant and long-term antibacterial bioactive nanocomposite coating is successfully fabricated on titanium surface through the strategy established in this study