Intermittent Administration of Parathyroid Hormone Enhances Odonto/Osteogenic Differentiation of Stem Cells from the Apical Papilla via JNK and P38 MAPK Pathways.

OBJECTIVE: Parathyroid hormone (PTH) is considered to be essential during the tooth development. Stem cells from the apical papilla (SCAPs) are responsible for dentine formation. However, the interaction between PTH and SCAPs remains unclear. This study was aimed at investigating the effects of PTH on odonto/osteogenic differentiation capacity of SCAPs and elucidating the underlying molecular mechanisms. Materials and Methods. Here, SCAPs were isolated and identified in vitro. Effects of PTH on the proliferation of SCAPs were determined by Cell Counting Kit-8 (CCK-8), flow cytometry (FCM), and EdU. Alkaline phosphatase (ALP) activity, alizarin red staining, Western blot, and RT-PCR were carried out to detect the odonto/osteogenic differentiation of PTH-treated SCAPs as well as the participation of the MAPK signaling pathway. RESULTS: An ALP activity assay determined that 10-8 mol/L PTH was the optimal concentration for the induction of SCAPs with no significant influence on the proliferation of SCAPs as indicated by CCK-8, FCM, and EdU. The expression of odonto/osteogenic markers was significantly upregulated in mRNA levels and protein levels. Moreover, intermittent treatment of PTH also increased phosphorylation of JNK and P38, and the differentiation was suppressed following the inhibition of JNK and P38 MAPK pathways. CONCLUSION: PTH can regulate the odonto/osteogenic differentiation of SCAPs via JNK and P38 MAPK pathways.

Yunnan Baiyao Conditioned Medium Promotes the Odonto/Osteogenic Capacity of Stem Cells from Apical Papilla via Nuclear Factor Kappa B Signaling Pathway.

Yunnan Baiyao is a traditional Chinese herbal remedy that has long been used for its characteristics of wound healing, bone regeneration, and anti-inflammation. However, the effects of Yunnan Baiyao on the odonto/osteogenic differentiation of stem cells from apical papilla (SCAPs) and the potential mechanisms remain unclear. The aim of this study was to investigate the odonto/osteogenic differentiation effects of Yunnan Baiyao on SCAPs and the underlying mechanisms involved. SCAPs were isolated and cocultured with Yunnan Baiyao conditioned media. The proliferation ability was determined by cell counting kit 8 and flow cytometry. The differentiation capacity and the involvement of NF-κB pathway were investigated by alkaline phosphatase assay, alizarin red staining, immunofluorescence assay, real-time RT-PCR, and western blot analyses. Yunnan Baiyao conditioned medium at the concentration of 50 µg/mL upregulated alkaline phosphatase activity, induced more mineralized nodules, and increased the expression of odonto/osteogenic genes/proteins (e.g., OCN/OCN, OPN/OPN, OSX/OSX, RUNX2/RUNX2, ALP/ALP, COL-I/COL-I, DMP1, DSP/DSPP) of SCAPs. In addition, the expression of cytoplasmic phos-IκBα, phos-P65, and nuclear P65 was significantly increased in Yunnan Baiyao conditioned medium treated SCAPs in a time-dependent manner. Conversely, the differentiation of Yunnan Baiyao conditioned medium treated SCAPs was obviously inhibited when these stem cells were cocultured with the specific NF-κB inhibitor BMS345541. Yunnan Baiyao can promote the odonto/osteogenic differentiation of SCAPs via the NF-κB signaling pathway.

Medical information security in the era of artificial intelligence.

In recent years, biometric technologies, such as iris, facial, and finger vein recognition, have reached consumers and are being increasingly applied. However, it remains unknown whether these highly specific biometric technologies are as safe as declared by their manufacturers. As three-dimensional (3D) reconstruction based on medical imaging and 3D printing are being developed, these biometric technologies may face severe challenges.