Injectable platelet-rich fibrin positively regulates osteogenic differentiation of stem cells from implant hole via the ERK1/2 pathway.

Bone regeneration in dentistry is a dynamic approach for treating critical size bone defects that are unlikely to self-heal. Human bone marrow stem cell (hBMSCs) therapies are being tested clinically for various disorders and have remarkable clinical advancements in bone regeneration. Injectable platelet-rich fibrin (i-PRF), which is obtained from autologous blood centrifuged at 700 rpm (60 G) for 3 min can promote osteogenic differentiation of this cell, but the mechanism remains unclear. The objectives of this study were to explore the contents of i-PRF further and investigate its effect on the cell behavior of hBMSCs and the underlying molecular mechanisms. The results showed that i-PRF contained 41 cytokines, including macrophage colony-stimulating factor (M-CSF) and ß-nerve growth factor (ß-NGF), which had not been reported before. The Cell Counting Kit-8 and wound healing assay showed that 10% and 20% i-PRF improved the proliferation rate and the migration capacity of hBMSCs without toxicity to cells. Besides, the expression of osteogenic markers and the capacity to form mineralized nodules of hBMSCs were promoted by 20% i-PRF. Furthermore, i-PRF activated the ERK pathway, and the ERK inhibitor attenuated its effects. In summary, i-PRF promotes hBMSCs proliferation and migration and facilitates cell osteogenesis through the ERK pathway, which has promising potential in bone regeneration.

What is the context? Bone defects caused by trauma or tumor is a great challenge in clinical practice. However, there is the good news that the bone defect in the oral can self-regenerate, the bone remodeling may take several months to several years and shows apparent individual differences.Different strategies, surgical techniques, and materials have been employed to induce an optimal outcome in guided bone regeneration.Blood products have been widely used in dentistry due to their excellent biocompatibility, growth factor content, ease of collection, and ability to be produced by the human body.Limited data suggest that Injectable platelet-rich fibrin positively regulates osteogenic differentiation of stem cells, but further evidence is needed to quantify this effect.What is new? It is unclear how many growth factors i-PRF contains in previous studies, so we detected 41 kinds of growth factors, more than has been previously appreciated, and found that all growth factors were measured in the samples, and the difference was in the amount of expression.In our research, we explored the role of i-PRF in the osteogenesis of hBMSCs through the effects of different concentrations of i-PRF on the proliferation, migration, and osteogenic differentiation of hBMSCs.Currently, most current research focuses on observing phenomena, and we wondered by what mechanism the i-PRF regulates stem cell function. We found that i-PRF can regulate the molecular mechanism of the osteogenic differentiation of hBMSCs in vitro by activating the MAPK/ERK signaling pathway.What is the impact?I-PRF promotes hBMSCs proliferation and migration and facilitates cell osteogenesis through the ERK pathway. The favorable cytobiological effects of i-PRF on hBMSCs might be the basis for i-PRF applications in bone regenerative.

An injectable PC10ARGD/Cu2+/DOX hydrogel for combined chemodynamic and chemotherapy of tumors.

Nowadays, chemotherapy is a common clinical treatment for cancer, but it still faces many limitations and challenges. Therefore, the combination of chemotherapy and other treatments often enhances the effectiveness of treatments. Herein, an injectable hydrogel of PC10ARGD/Cu2+/DOX based on Cu2+, hydrophilic doxorubicin (DOX), and genetically engineered polypeptide PC10ARGD was prepared. First, Cu2+ was attached to the histidines in the PC10ARGD polypeptide by the coordination reaction to form PC10ARGD/Cu2+ hydrogel, then the PC10ARGD/Cu2+/DOX hydrogel was prepared by encapsulating the DOX into the PC10ARGD/Cu2+ hydrogel. The results of scanning electron microscopy showed that the PC10ARGD/Cu2+/DOX hydrogel displayed loose porous morphology. In vitro, reactive oxygen species production results showed that the PC10ARGD/Cu2+/DOX hydrogel could continuously produce ·OH in the presence of H2O2. In vitro MTT results showed that the PC10ARGD/Cu2+/DOX hydrogel had a good inhibitory effect on cell activity. Flow cytometry further confirmed the antitumor effect of the PC10ARGD/Cu2+/DOX hydrogel. In vivo experiment results showed that the tumor volume of mice treated with the PC10ARGD/Cu2+/DOX hydrogel was significantly inhibited compared with control groups, which was due to the combination of chemodynamic and chemotherapy. The results of body weight and blood analysis of mice showed that the PC10ARGD/Cu2+/DOX hydrogel possessed good biocompatibility.

Injectable enzyme-catalyzed crosslinking hydrogels as BMSCs-laden tunable scaffold for osteogenic differentiation.

Bone defects caused by trauma or tumor are a significant challenge in clinical practice. Hydrogel-based tissue engineering has been considered an effective strategy. This study successfully formed a series of injectable hydrogels by enzyme-catalyzed crosslinking hyaluronic acid-tyramine (HA-TA) and sodium alginate-tyramine (ALG-TA) under physiological conditions in the presence of both horseradish peroxidase and hydrogen peroxide. The morphology, mechanical properties, swelling properties, and biodegradation properties of hydrogels were investigated. The results showed that the mechanical properties, swelling properties and biodegradation of HA/ALG hydrogels varied with the precursor solution concentration. Furthermore, the proliferation and osteogenic differentiation of BMSCs within the HA/ALG hydrogels were evaluated in vitro. The results illustrated that the hydrogels could offer an excellent microenvironment for BMSCs growth and promote osteogenic differentiation. Therefore, the injectable hydrogels can be used as an effective 3 D scaffold for bone repair and regeneration.

Regulating the electronic and magnetic properties of 1T'-ReS2 by fabricating nanoribbons and transition-metal doping: a theoretical study.

Monolayer 1T'-type rhenium disulphide (1T'-ReS2) has promising applications in spintronic devices due to its unique electronic properties induced by inversion loss in the crystal structure. A prerequisite of such applications is introducing magnetism in 1T'-ReS2. Here, we studied the electronic and magnetic properties of zigzag 1T'-ReS2 nanoribbons (1T'-ReS2-NRs) and further tuned their magnetic properties by transition-metal doping. Our results show that 1T'-ReS2-NRs exhibit tunable electronic properties ranging from indirect bandgap to direct bandgap to metallic properties. Among the energy-favoured S-terminated 1T'-ReS2-NRs, only one exhibits robust magnetic properties. The magnetic properties of the other two nanoribbons can be effectively tuned by doping with certain transition metals. Among the configurations of TM-doped 1T'-ReS2-NRs, only those with TM atoms introduced at the edge sites are energy-favoured. The magnetic properties of TM-doped 1T'-ReS2-NRs are mainly contributed by the TM atom, the Re and S atoms at the edges of the nanoribbons. Besides this, the bulk Re and S atoms close to the TM atom also contribute positively to the magnetism and such contributions become weaker as the atoms are farther from the TM atom. These results provide deep insights into the modulations of the electronic and magnetic properties of 1T'-ReS2 at the atomic scale, and thus should pave an effective path for fabricating 2D materials for spintronic devices.

A visible human body slice segmentation method framework based on OneCut and adjacent image geometric features.

As a recent research hot issue, obtaining the accurate 3 D organ models of Visible Human Project (VHP) has many significances. Therefore, how to extract the organ regions of interest (ROI) in the large-scale color slice image data set has become an urgent issue to be solved. In this paper, we propose a method framework based on OneCut algorithm and adjacent image geometric features to continuously extract the main organ regions is proposed. This framework mainly contains two parts: firstly, the OneCut algorithm is used to segment the ROI of target organ in the current image; secondly, the foreground image (obtained ROI) is corroded into several seed points and the background image (other region except for ROI) is refined into a skeleton. Then the obtained seed points and skeleton can be transmitted and mapped onto the next image as the input of OneCut algorithm. Thereby, the serialized slice images can be processed continuously without manual delineating. The experimental results show that the extracted VHP organs are satisfactory. This method framework may provide well technic foundation for other related application.