RESUMEN
Mesenchymal stem/stromal cells (MSCs)-based therapy brings the reassuring capability to regenerative medicine through their self-renewal and multilineage potency. Also, they secret a diversity of mediators, which are complicated in moderation of deregulated immune responses, and yielding angiogenesis in vivo. Nonetheless, MSCs may lose biological performance after procurement and prolonged expansion in vitro. Also, following transplantation and migration to target tissue, they encounter a harsh milieu accompanied by death signals because of the lack of proper tensegrity structure between the cells and matrix. Accordingly, pre-conditioning of MSCs is strongly suggested to upgrade their performances in vivo, leading to more favored transplantation efficacy in regenerative medicine. Indeed, MSCs ex vivo pre-conditioning by hypoxia, inflammatory stimulus, or other factors/conditions may stimulate their survival, proliferation, migration, exosome secretion, and pro-angiogenic and anti-inflammatory characteristics in vivo. In this review, we deliver an overview of the pre-conditioning methods that are considered a strategy for improving the therapeutic efficacy of MSCs in organ failures, in particular, renal, heart, lung, and liver.
Asunto(s)
Exosomas , Trasplante de Células Madre Mesenquimatosas , Riñón , Medicina Regenerativa/métodos , Pulmón , Células del Estroma , Trasplante de Células Madre Mesenquimatosas/métodosRESUMEN
Periodontitis, as a complex inflammatory disorder, is characterized by continuous destruction of the teeth-supporting components, like alveolar bone and periodontal ligament, and affects a great percentage of individuals over the world. Also, this oral disease is linked with multiple serious illnesses, e.g., cardiovascular disorders, diabetes, and oral cancer; thus, exerting efficient therapy for periodontitis is necessary. Unfortunately, the current therapies for the disease (e.g., surgical and nonsurgical methods) have not reflected enough effectiveness against periodontitis. At present, mesenchymal stem cell (MSC)-based remedy has created new hope for curating different diseases; however, MSCs have no capability to engraft into the chosen tissue, and the tumorigenic influences of MSCs are still the main concern. Interestingly, documents have revealed that MSC-derived mediators, like exosomes, which their exploitation is more feasible than intact MSCs, can be an effective therapeutic candidate for periodontitis. Therefore, in this study, we will review evidence in conjunction with their possible curative impacts on periodontitis cases.
Asunto(s)
Exosomas , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Periodontitis , Humanos , Trasplante de Células Madre Mesenquimatosas/métodos , Periodontitis/terapia , Ligamento PeriodontalRESUMEN
Platform-switching reduces peri-implant marginal bone loss (MBL). The aim of this study was to compare the effect of platform-switching on stress within crestal bone using different implant-abutment mismatches (0.65 and 1 mm) under 2 different vertical loads (30 N vs 200 N) for implants placed in posterior jaw sites. Three-dimensional modeling software was used for an implant with a diameter of 4.5 mm and length of 13 mm. Molars were modeled using computerized tomography images of bone density in human maxilla (D3 bone) and mandible (D2 bone). Collected data were analyzed using CATIA software. In posterior mandible, stress of 30 N force with platform mismatches of 0.65 or 1 mm were 2.920 and 2.440 MPa respectively. Using 200 N force, values increased to 19.44 and 16.30 MPa. In posterior maxilla and 30 N force, stresses with mismatches of 0.65 and 1 mm were 3.77 and 3.18 MPa, respectively, increasing to 25.14 and 20.17 MPa with 200 N force. The effect can be predicted to be greatest as the mismatch increases with implants placed into lower quality bone (posterior maxilla with D3 quality).