The effect of injectable platelet-rich fibrin and platelet-rich fibrin in regenerative endodontics: a comparative in vitro study.

OBJECTIVE: To explore the feasibility of injectable platelet-rich fibrin (i-PRF) in regenerative endodontics by comparing the effect of i-PRF and platelet-rich fibrin (PRF) on the biological behavior and angiogenesis of human stem cells from the apical papilla (SCAPs). METHODOLOGY: i-PRF and PRF were obtained from venous blood by two different centrifugation methods, followed by hematoxylin-eosin (HE) staining and scanning electron microscopy (SEM). Enzyme-linked immunosorbent assay (ELISA) was conducted to quantify the growth factors. SCAPs were cultured with different concentrations of i-PRF extract (i-PRFe) and PRF extract (PRFe), and the optimal concentrations were selected using the Cell Counting Kit-8 (CCK-8) assay. The cell proliferation and migration potentials of SCAPs were then observed using the CCK-8 and Transwell assays. Mineralization ability was detected by alizarin red staining (ARS), and angiogenesis ability was detected by tube formation assay. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to evaluate the expression of genes related to mineralization and angiogenesis. The data were subjected to statistical analysis. RESULTS: i-PRF and PRF showed a similar three-dimensional fibrin structure, while i-PRF released a higher concentration of growth factors than PRF ( P <.05). 1/4× i-PRFe and 1/4× PRFe were selected as the optimal concentrations. The cell proliferation rate of the i-PRFe group was higher than that of the PRFe group ( P <.05), while no statistical difference was observed between them in terms of cell mitigation ( P >.05). More importantly, our results showed that i-PRFe had a stronger effect on SCAPs than PRFe in facilitating mineralization and angiogenesis, with the consistent result of RT-qPCR ( P <.05). CONCLUSION: This study revealed that i-PRF released a higher concentration of growth factors and was superior to PRF in promoting proliferation, mineralization and angiogenesis of SCAPs, which indicates that i-PRF could be a promising biological scaffold for application in pulp regeneration.

MicroRNA-125b mediates Interferon-γ-induced downregulation of the vitamin D receptor in systemic lupus erythematosus.

BACKGROUND: The inflammatory factor interferon (IFN)-γ is related to the occurrence and development of systemic lupus erythematosus (SLE). The vitamin D receptor (VDR) has an anti-inflammatory effect and its downregulation is involved in the onset of SLE. Our previous studies have confirmed that the expression of VDR in SLE peripheral blood mononuclear cells (PBMCs) is downregulated, which is negatively correlated with disease activity and inflammation. However, the mechanism underlying VDR downregulation in SLE is unknown. METHODS: Based on the results of computer simulation analysis, the expression of VDR and four microRNAs (miR-17-3p, miR-34a, miR-346, and miR-125b) in SLE PBMC cells was analyzed under proinflammatory cytokine IFN­Î³ treatment, and miR-125b was identified as the target miRNA. The relationship between IFN­Î³, miR-125b, and VDR was further assessed in THP­1 cells. RESULTS: We showed that IFN­Î³ inhibited the expression of VDR and miR-125b. Further study revealed that VDR mRNA was positively correlated with miR-125b in THP­1 cells after IFN­Î³ intervention. After transfection of miR-125b mimic or inhibitor, the expression of VDR in the miR-125b inhibitor group was lower than in the control group and miR-125b mimic group, while expression in the control group was lower than in miR-125b mimic group. Transfection of miR-125b inhibitor into THP­1 cells could further promote the ability of IFN­Î³ to inhibit VDR. CONCLUSION: The decrease in VDR expression promotes development of inflammation and SLE. These data suggest that miR-125b may mediate inflammatory factor IFN-γ-induced downregulation of VDR in the pathogenesis of SLE.

The effect of injectable platelet-rich fibrin and platelet-rich fibrin in regenerative endodontics: a comparative in vitro study

Abstract Objective To explore the feasibility of injectable platelet-rich fibrin (i-PRF) in regenerative endodontics by comparing the effect of i-PRF and platelet-rich fibrin (PRF) on the biological behavior and angiogenesis of human stem cells from the apical papilla (SCAPs). Methodology i-PRF and PRF were obtained from venous blood by two different centrifugation methods, followed by hematoxylin-eosin (HE) staining and scanning electron microscopy (SEM). Enzyme-linked immunosorbent assay (ELISA) was conducted to quantify the growth factors. SCAPs were cultured with different concentrations of i-PRF extract (i-PRFe) and PRF extract (PRFe), and the optimal concentrations were selected using the Cell Counting Kit-8 (CCK-8) assay. The cell proliferation and migration potentials of SCAPs were then observed using the CCK-8 and Transwell assays. Mineralization ability was detected by alizarin red staining (ARS), and angiogenesis ability was detected by tube formation assay. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to evaluate the expression of genes related to mineralization and angiogenesis. The data were subjected to statistical analysis. Results i-PRF and PRF showed a similar three-dimensional fibrin structure, while i-PRF released a higher concentration of growth factors than PRF ( P <.05). 1/4× i-PRFe and 1/4× PRFe were selected as the optimal concentrations. The cell proliferation rate of the i-PRFe group was higher than that of the PRFe group ( P <.05), while no statistical difference was observed between them in terms of cell mitigation ( P >.05). More importantly, our results showed that i-PRFe had a stronger effect on SCAPs than PRFe in facilitating mineralization and angiogenesis, with the consistent result of RT-qPCR ( P <.05). Conclusion This study revealed that i-PRF released a higher concentration of growth factors and was superior to PRF in promoting proliferation, mineralization and angiogenesis of SCAPs, which indicates that i-PRF could be a promising biological scaffold for application in pulp regeneration.

[Neutrophil-lymphocyte and platelet-lymphocyte ratios for assessing disease activity in patients with rheumatoid arthritis receiving tofacitinib treatment].

OBJECTIVE: To evaluate the value of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) for assessing disease activity in patients with rheumatoid arthritis (RA) treated with tofacitinib. METHODS: This retrospective study was conducted among 98 RA patients in active stage treated with tofacitinib in Third Xiangya Hospital and 100 healthy control subjects from the Health Management Center of the hospital from 2019 to 2021. We collected blood samples from all the participants for measurement of erythrocyte sedimentation rate (ESR), high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and other blood parameters 1 month before and 6 months after tofacitinib treatment. We further evaluated PLR and NLR before and after tofacitinib treatment in the RA patients, and analyzed their correlations with RA disease activity. RESULTS: PLR and NLR increased significantly in RA patients as compared with the healthy controls. In the RA patients, PLR and NLR were positively correlated with the levels of hs- CRP, ESR, IL- 6, Disease Activity Score of 28 joints-ESR (DAS28-ESR), anti-cyclic citrullinated peptide (CCP), and rheumatoid factor (RF) before and after tofacitinib treatment. Tofacitinib treatment for 6 months significantly decreased hs-CRP, ESR, IL-6, CCP, RF and DAS28-ESR levels in the RA patients. CONCLUSION: NLR and PLR can be useful biomarkers for assessing disease activity in RA patients treated with tofacitinib.

Effects of immunoglobulin Y-loaded amorphous calcium phosphate on dentinal tubules occlusion and antibacterial activity.

Aim: This study aimed to evaluate the effects of immunoglobulin Y (IgY)-loaded amorphous calcium phosphate (ACP) (IgY@ACP) on dentinal tubule occlusion and antibacterial activity. Methodology: IgY@ACP was synthesized based on a biomimetic mineralization strategy. The structure was examined by transmission electron microscopy and Fourier transform infrared spectroscopy. The IgY release property was assessed in vitro. The cell biocompatibility of IgY@ACP was evaluated by CCK-8. The dentin disks were prepared using healthy human molars, and their dentinal tubules were exposed to EDTA. Subsequently, they were randomly selected and treated with or without IgY@ACP for 7 days. The tubule occlusion morphologies and newly formed layers were observed by scanning electron microscopy (SEM) and x-ray diffraction, respectively. To evaluate the acid resistance and abrasion resistance of IgY@ACP, dentin disks that were treated for 1 day were immersed in acid solution or subjected to a toothbrush. The antibacterial effects against Streptococcus mutans (S. mutans) were evaluated by colony-forming unit (CFU) counting, adhesion property assessment, and crystal violet and live/dead bacterial staining. Finally, the occlusion effect was evaluated in rat incisors in vivo. One-way analysis of variance (ANOVA) was performed for statistical analysis. The level of significance was set at 0.05. Results: IgY@ACP presented an amorphous phase with a nanosize (60-80 nm) and sustained release of protein within 48 h. The CCK-8 results showed that IgY@ACP had good biocompatibility. After treatment with IgY@ACP for 1 day, the majority of dentinal tubules were occluded by a 0.3-µm-thick mineralized layer. Seven days later, all dentinal tubules were occluded by mineralization with a thickness of 1.4 µm and a depth of 16 µm. The newly mineralized layer showed hydroxyapatite-like diffraction peaks. In addition, IgY@ACP had good acid and abrasion resistance. After treatment with IgY@ACP, the CFU counting and adhesion rate of S. mutans were significantly reduced, the crystal violet staining was lighter, and the S. mutans staining revealed more dead cells. Most importantly, IgY@ACP had a certain occluding property in rat incisors in vivo. Conclusion: IgY@ACP can effectively occlude dentinal tubules with acid-resistant stability and has prominent anti-S. mutans effects, rendering it a potentially suitable desensitization material in the clinic.