A review on gold nanoparticles as an innovative therapeutic cue in bone tissue engineering: Prospects and future clinical applications.

Bone damage is a complex orthopedic problem primarily caused by trauma, cancer, or bacterial infection of bone tissue. Clinical care management for bone damage remains a significant clinical challenge and there is a growing need for more advanced bone therapy options. Nanotechnology has been widely explored in the field of orthopedic therapy for the treatment of a severe bone disease. Among nanomaterials, gold nanoparticles (GNPs) along with other biomaterials are emerging as a new paradigm for treatment with excellent potential for bone tissue engineering and regenerative medicine applications. In recent years, a great deal of research has focused on demonstrating the potential for GNPs to provide for enhancement of osteogenesis, reduction of osteoclastogenesis/osteomyelitis, and treatment of bone cancer. This review details the latest understandings in regards to GNPs based therapeutic systems, mechanisms, and the applications of GNPs against various bone disorders. The present review aims to summarize i) the mechanisms of GNPs in bone tissue remodeling, ii) preparation methods of GNPs, and iii) functionalization of GNPs and its decoration on biomaterials as a delivery vehicle in a specific bone tissue engineering for future clinical application.

Development of a Temperature-Responsive Hydrogel Incorporating PVA into NIPAAm for Controllable Drug Release in Skin Regeneration.

Melanoma, a highly malignant and aggressive form of skin cancer, poses a significant global health threat, with limited treatment options and potential side effects. In this study, we developed a temperature-responsive hydrogel for skin regeneration with a controllable drug release. The hydrogel was fabricated using an interpenetrating polymer network (IPN) of N-isopropylacrylamide (NIPAAm) and poly(vinyl alcohol) (PVA). PVA was chosen for its adhesive properties, biocompatibility, and ability to address hydrophobicity issues associated with NIPAAm. The hydrogel was loaded with doxorubicin (DOX), an anticancer drug, for the treatment of melanoma. The NIPAAm-PVA (N-P) hydrogel demonstrated temperature-responsive behavior with a lower critical solution temperature (LCST) around 34 °C. The addition of PVA led to increased porosity and faster drug release. In vitro biocompatibility tests showed nontoxicity and supported cell proliferation. The N-P hydrogel exhibited effective anticancer effects on melanoma cells due to its rapid drug release behavior. This N-P hydrogel system shows great promise for controlled drug delivery and potential applications in skin regeneration and cancer treatment. Further research, including in vivo studies, will be essential to advance this hydrogel system toward clinical translation and impactful advancements in regenerative medicine and cancer therapeutics.

Development of a plasma-based 3D printing system for enhancing the biocompatibility of 3D scaffold.

Fused deposition modeling (FDM) is a three-dimensional (3D) printing technology typically used in tissue engineering. However, 3D-printed row scaffolds manufactured using material extrusion techniques have low cell affinity on the surface and an insufficient biocompatible environment for desirable tissue regeneration. Thus, in this study, plasma treatment was used to render surface modification for enhancing the biocompatibility of 3D-printed scaffolds. We designed a plasma-based 3D printing system with dual heads comprising a plasma device and a regular 3D FDM printer head for a layer-by-layer nitrogen plasma treatment. Accordingly, the wettability, roughness, and protein adsorption capability of the 3D-printed scaffold significantly increased with the plasma treatment time. Hence, the layer-by-layer plasma-treated (LBLT) scaffold exhibited significantly enhanced cell adhesion and proliferation in anin vitroassay. Furthermore, the LBLT scaffold demonstrated a higher tissue infiltration and lower collagen encapsulation than those demonstrated by a non-plasma-treated scaffold in anin vivoassay. Our approach has great potential for various tissue-engineering applications via the adjustment of gas or precursor levels. In particular, this system can fabricate scaffolds capable of holding a biocompatible surface on an entire 3D-printed strut. Thus, our one-step 3D printing approach is a promising platform to overcome the limitations of current biocompatible 3D scaffold engineering.

Ginseng-derived exosome-like nanovesicles extracted by sucrose gradient ultracentrifugation to inhibit osteoclast differentiation.

Plant-derived extracellular nanovesicles contain RNA and proteins with unique and diverse pharmacological mechanisms. The extracellular nanovesicles encapsulating plant extracts resemble exosomes as they have a round, lipid bilayer morphology. Ginseng is anti-inflammatory, anti-cancer, immunostimulant, and osteogenic/anti-osteoporotic. Here, we confirmed that ginseng-derived extracellular nanovesicles (GDNs) inhibit osteoclast differentiation and elucidated the associated molecular mechanisms. We isolated GDNs by centrifugation with a sucrose gradient. We measured their dynamic light scattering and zeta potentials and examined their morphology by transmission electron microscopy. We used bone marrow-derived macrophages (BMMs) to determine the potential cytotoxicity of GDNs and establish their ability to inhibit osteoclast differentiation. The GDNs treatment maintained high BMM viability and proliferation whilst impeding osteoclastogenesis. Tartrate-resistant acid phosphatase and F-actin staining revealed that GDNs at concentrations >1 µg mL-1 strongly hindered osteoclast differentiation. Moreover, they substantially suppressed the RANKL-induced IκBα, c-JUN n-terminal kinase, and extracellular signal-regulated kinase signaling pathways and the genes regulating osteoclast maturation. The GDNs contained elevated proportions of Rb1 and Rg1 ginsenosides and were more effective than either of them alone or in combination at inhibiting osteoclast differentiation. In vivo bone analysis via microcomputerized tomography, bone volume/total volume ratios, and bone mineral density and bone cavity measurements demonstrated the inhibitory effect of GDNs against osteoclast differentiation in lipopolysaccharide-induced bone resorption mouse models. The results of this work suggest that GDNs are anti-osteoporotic by inhibiting osteoclast differentiation and are, therefore, promising for use in the clinical prevention and treatment of bone loss diseases.

Super-Resolving Methodology for Noisy Unpaired Datasets.

Although it is possible to acquire high-resolution and low-resolution paired datasets, their use in directly supervised learning is impractical in real-world applications. In the present work, we focus on a practical methodology for image acquisition in real-world conditions. The main method of noise reduction involves averaging multiple noisy input images into a single image with reduced noise; we also consider unpaired datasets that contain misalignments between the high-resolution and low-resolution images. The results show that when more images are used for average denoising, better performance is achieved in the super-resolution task. Quantitatively, for a fixed noise level with a variance of 60, the proposed method of using 16 images for average denoising shows better performance than using 4 images for average denoising; it shows 0.68 and 0.0279 higher performance for the peak signal-to-noise ratio and structural similarity index map metrics, as well as 0.0071 and 1.5553 better performance for the learned perceptual image patch similarity and natural image quality evaluator metrics, respectively.

Development of photo-crosslinkable platelet lysate-based hydrogels for 3D printing and tissue engineering.

Three-dimensional (3D) printing shows potential for use as an advanced technology for forming biomimetic tissue and other complex structures. However, there are limits and restrictions on selection of conventional bioinks. Here we report the first 3D-printable platelet lysate (PLMA)-based hydrogel, which consists of platelet lysate from whole blood of humans that can simulate the 3D structure of tissues and can be formed into a crosslinked hydrogel layer-by-layer to build cell-laden hydrogel constructs through methacrylated photo-polymerization. Furthermore, it can be customized for use with various tissues by controlling the physical properties according to irradiation time and concentration. In particular, different cells can be mixed and printed, and the integrity of the 3D printed structure can maintain its shape after crosslinking. The bio-ink exhibits excellent cell diffusion and proliferation at low concentrations, which improves moldability and biocompatibility. The 3D-printable PLMA bioinks may constitute a new strategy to create customized microenvironments for the repair of various tissuesin vivousing materials derived from the human body.

Effect of oxygen plasma treatment on carbon nanotube-based sensors.

We present the research results of the use of plasma modification for the fabrication of carbon nanotube-based devices for chemical and biological sensing. The oxygen plasma treatment of multiwalled carbon nanotubes (MWCNTs) effectively grafts oxygen atoms onto the CNT surface. For investigating the impact of plasma modification on the MWCNT-based sensor performance, three different sensors are fabricated: NH3 gas sensors, humidity sensors, and immunosensors. The plasma-modified MWCNTs (p-MWCNTs) exhibit a sensitivity to NH3 that is approximately twice that of the corresponding untreated sensor. The humidity sensor with a p-MWCNT top electrode exhibits a much faster response time compared with the untreated MWCNT electrodes. The p-MWCNT immunosensor exhibits a detection limit almost 1000 times lower than that of the standard ELISA assay, while the untreated MWCNTs exhibit no detectable signal. These results imply that the oxygen-containing functional groups on the CNT surface significantly affect the performance of the CNT-based chemical and biological sensors.

An excimer emission approach for patterned fluorescent imaging.

Selective removal of t-Boc protecting groups in a polymer film imbedded, pyrene-containing calixarene derivative results in the generation of a patterned fluorescence image without employing wet developing processes.