Cold plasma treatment increases the hydrophilicity of the surfaces of implants and may enhance their integration with the surrounding tissues. The implaPrep prototype device from Relyon Plasma generates cold atmospheric plasma via dielectric barrier discharge (DBD). In this study, titanium surfaces were treated with the implaPrep device for 20 s and assessed as a cell culture surface for fibroblasts. One day after seeding, significantly more cells were counted on the surfaces treated with cold plasma than on the untreated control titanium surface. Additionally, the viability assay revealed significantly higher viability on the treated surfaces. Morphological observation of the cells showed certain differences between the treated and untreated titanium surfaces. While conventional plasma devices require compressed gas, such as oxygen or argon, the implaPrep device uses atmospheric air as the gas source. It is, therefore, compact in size and simple to handle, and may provide a safe and convenient tool for treating the surfaces of dental implants, which may further improve the implantation outcome.
Human dental pulp stem cells (hDPSCs) are multipotent mesenchymal stem cells (MSCs) that are capable of self-renewal with multilineage differentiation potential. After being cryopreserved, hDPSCs were reported to maintain a high level of proliferation and multi-differentiation abilities. In order to optimize cryopreservation techniques, decrease storage requirements and lower contamination risks, the feasibility of new whole-tooth cryopreservation and its effects on hDPSCs were tested. The survival rates, morphology, proliferation rates, cell activity, surface antigens and differentiation abilities of hDPSCs isolated from fresh teeth were compared with those of one-month cryopreserved teeth in 5% and 10% DMSO. The data of the present study indicated that the new cryopreservation approach did not reduce the capabilities or stemness of hDPSCs, with the exception that it extended the first appearance time of hDPSCs in the teeth that were cryopreserved in 10% DMSO, and reduced their recovery rate. With the novel strategy of freezing, the hDPSCs still expressed the typical surface markers of MSCs and maintained excellent proliferation capacity. Three consecutive weeks of osteogenic and adipogenic induction also showed that the expression of the key genes in hDPSCs, including lipoprotein lipase (LPL), peroxisome proliferator-activated receptor-γ (PPAR-γ), alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2), type I collagen (COL I) and osteocalcin (OSC) was not affected, indicating that their differentiation abilities remained intact, which are crucial parameters for hDPSCs as cell-therapy candidates. These results demonstrated that the new cryopreservation method is low-cost and effective for the good preservation of hDPSCs without compromising cell performance, and can provide ideas and evidence for the future application of stem-cell therapies and the establishment of dental banks.
Objective: Despite numerous existing treatments for keloids, the responses in the clinic have been disappointing, due to either low efficacy or side effects. Numerous studies dealing with preclinical and clinical trials have been published about effective therapies for fibrotic diseases using mesenchymal stem cells; however, no research has yet been reported to scientifically investigate the effect of human dental pulp stem cells (HDPSCs) on the treatment of keloids. The objective is to provide an experimental basis for the application of stem cells in the treatment of keloids. Methods: Human normal fibroblasts (HNFs) and human keloid fibroblasts (HKFs) were cultured alone and in combination with HDPSCs using a transwell cell-contact-independent cell culture system. The effects of HDPSCs on HKFs were tested using a CCK-8 assay, live/dead staining assay, quantitative polymerase chain reaction, Western blot and immunofluorescence microscopy. Results: HDPSCs did not inhibit the proliferation nor the apoptosis of HKFs and HNFs. HDPSCs did, however, inhibit their migration. Furthermore, HDPSCs significantly decreased the expression of profibrotic genes (CTGF, TGF-β1 and TGF-β2) in HKFs and KNFs (p < 0.05), except for CTGF in HNFs. Moreover, HDPSCs suppressed the extracellular matrix (ECM) synthesis in HKFs, as indicated by the decreased expression of collagen I as well as the low levels of hydroxyproline in the cell culture supernatant (p < 0.05). Conclusions: The co-culture of HDPSCs inhibits the migration of HKFs and the expression of pro-fibrotic genes, while promoting the expression of anti-fibrotic genes. HDPSCs’ co-culture also inhibits the synthesis of the extracellular matrix by HKFs, whereas it does not affect the proliferation and apoptosis of HKFs. Therefore, it can be concluded that HDPSCs can themselves be used as a tool for restraining/hindering the initiation or progression of fibrotic tissue.
22 August 2024 in QJM: An International Journal of Medicine
Introduction: The mechanism underlying the relationship between Alzheimer’s disease (AD) and minerals (serum calcium, copper, iron, magnesium, zinc), vitamins (25-OH vitamin D, vitamin A1 [retinol], B9 [folic acid], B12, C) is unclear. Methods: In a two-step Mendelian randomization analysis, the association between positive nutritional elements and 3935 magnetic resonance images (MRI) phenotypes was examined, and the mediation proportion was calculated. Horizontal pleiotropy and heterogeneity of MR were assessed using MR-Egger, Cochran’s Q test, MR-PRESSO. RESULTS: 25-OH vitamin D (P = 0.0019, OR = 0.6179, 95% CI = 0.4562–0.8368, inverse weighted variance [IVW]) is negatively associated with AD among 10 nutrients. The mediation proportion of the effect of vitamin D on AD mediated by IDP_dMRI_TBSS_L3_Superior_fronto-occipital_fasciculus_L was ∼7.08%. Discussion: Our results support 25-OH vitamin D as a causal protective factor for Alzheimer disease. It was found that the Superior_fronto-occipital_fasciculus_L may play a minimal mediating role.
The aim of this study was to investigate the effect of dental pulp stem cell-derived exosomes (DPSCs-Exos) on the biological behaviour of fibroblasts, particularly on keloid fibroblasts (KFs) and normal skin fibroblasts (NFs), with a view to providing new insights into cellular regenerative medicine. We obtained DPSCs-Exos by ultracentrifugation and co-cultured it with KFs and NFs. We detected its effect on cell proliferation using the CCK-8 assay; cell migration ability by cell scratch and Transwell assays; extracellular matrix synthesis using the hydroxyproline content assay; the expression levels of genes associated with fibrosis by PCR assay; and the expression levels of proteins related to fibrosis in the cells using the Western Blot method. DPSCs-Exos was able to be taken up by fibroblasts after addition to the culture medium and affected the biological behavior of NFs and KFs. DPSCs-Exos promoted the proliferation of NFs, inhibited the migration and extracellular matrix synthesis of KFs. In addition, DPSCs-Exos was able to inhibit the expression of fibrosis-related genes and proteins in KFs. This study highlights the role of DPSCs-Exos in regulating the biological behaviour of fibroblasts, providing new insights for future applications in the field of cell-free regenerative medicine.
Objectives: To explore the potential application of B-OT in the aspiration tract. Materials and Methods: We conceived and optimized an in vitro model simulating the mouth-washing process to assess tolerance to B-OT on primary human gingival fibroblasts. Cells derived from 4 unrelated donors were flushed with medium containing drugs of various concentration for one minute twice daily for 3 days. Results: No effect was seen on the cells up to 1000 µM B-OT. In addition, we treated the cells with B-OT permanently in medium, corresponding to a systemic treatment. No effect was seen by 10 µM B-OT and only a slight reduction (approximately 10%) was seen by 100 µM B-OT. Conclusions: Our results suggest good tolerance of oral cells for B-OT, favoring the further development of this antiviral reagent as a mouth-washing solution and nasal spray.