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Abstract Objective: The aim of this population-based retrospective study was to compare the osteogenic effect of newly formed bone after maxillary sinus floor elevation (MSFE) and simultaneous implantation with or without bone grafts by quantitatively analyzing trabecular bone parameters. Methodology: A total of 100 patients with missing posterior maxillary teeth who required MSFE and implantation were included in this study. Patients were divided into two groups: the non-graft group (n=50) and the graft group (n=50). Radiographic parameters were measured using cone beam computed tomography (CBCT), and the quality of newly formed bone was analyzed by assessing trabecular bone parameters using CTAn (CTAnalyzer, SkyScan, Antwerp, Belgium) software. Results: In the selected regions of interest, the non-graft group showed greater bone volume/total volume (BV/TV), bone surface/total volume (BS/TV), trabecular number (Tb. N), and trabecular thickness (Tb. Th) than the graft group (p<0.001). The non-graft group showed lower trabecular separation (Tb. Sp) than the graft group (p<0.001). The incidence of perforation and bleeding was higher in the graft group than in the non-graft group (p<0.001), but infection did not significantly differ between groups (p>0.05). Compared to the graft group, the non-graft group showed lower postoperative bone height, gained bone height and apical bone height (p<0.001). Conclusion: MSFE with and without bone grafts can significantly improve bone formation. In MSFE, the use of bone grafts hinders the formation of good quality bone, whereas the absence of bone grafts can generate good bone quality and limited bone mass.
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@#Cell therapy based on mesenchymal stem cells (MSCs) has been a hot research topic in recent years, including the traditional cell therapy strategy based on living cells and the new cell-free therapy strategy based on soluble proteins or bioactive molecules such as extracellular vesicles (EVs). At present, MSC-induced cells have mature functions and specific structures, and insitu transplantation combined with biomaterials or organic technology has greatly improved the settlement rate and function. On the other hand, as the large-scale culture technique and EVs separation technique evolve, it is possible to obtain a large number of pure EVs, and EVs are gradually becoming a hot spot of current research. An increasing number of studies have shown that the therapeutic effect of MSCs not only occurs by implantation and differentiation but also manifests as the paracrine effect of MSCs. In this review, we discuss the emerging outcomes of cell therapies and acellular therapies to alleviate these pathological conditions.
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@#Exosomes are phospholipid bilayer vesicles secreted by living cells that can carry a variety of signaling molecules, such as RNA, DNA, protein, and lipids. Exosomes play a role in the transmission of signaling molecules between cells, thus regulating many physiological and pathological processes. The methods of extracting exosomes include differential centrifugation, density gradient centrifugation, exclusion chromatography, ultrafiltration, coprecipitation, polymer immune affinity, microfluidic separation technology, etc. Each of these extraction technologies has advantages and disadvantages; however, there is no unified international standard. In addition, the expression of specific proteins and genetic material of exosomes from different cell sources are different; thus, their expression characteristics and functions are also distinctive. Based on this situation, research on exosomes is limited to preclinical studies, and difficulties and challenges still exist in clinical application. This paper summarizes the progress of research in the field of exosomes, to understand the characteristics, modification and application of exosomes from different cell sources, and to summarize their advantages and disadvantages as well as challenges, which can help researchers better understand and master the performance of exosomes. Furthermore, improvement of standard procedures in the extraction and manufacturing of exosomes is important, as it will provide a reference for researchers to carry out exosome-related translational clinical research.
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@# Stem cells are a class of undifferentiated cells with high self⁃renewal and rapid proliferative capabilities. Undercertain conditions, stem cells can induce differentiation into other tissue cells of the human body, such as skeletal muscle cells, cardiomyocytes, osteoblasts, and nerve⁃like cells. In recent years, with the development of tissue engineer⁃ ing and regenerative medicine, stem cells have been extensively used in various fields of regenerative medicine as opti⁃ mal seeded cells; however, there are still some problems, such as the decreased cell survival rate and regenerative ca⁃ pacity after transplantation, immune rejection, and ethical supervision. Therefore, it is difficult to universally and safely use stem cell banks for regeneration applications. The paracrine effect of stem cells has been extensively studied since its discovery. Increasing evidence supports the view that stem cells act in paracrine manner, and the secretion of exo⁃ somes plays a vital role in their biological functions. Exosomes are nanoscale extracellular vesicles containing biological⁃ ly active molecules such as RNA and proteins; they possess similar functions to stem cells and play important roles in cell communication, immune response, and repair of tissue damage. At present, clinical studies on stem cell exosomes in tissue engineering and regenerative medicine have also been carried out in the fields of bone and cartilage repair, nerve tissue regeneration, liver tissue regeneration, skeletal muscle tissue engineering, vascular regeneration, taste bud repair, tooth regeneration, etc. In this paper, the composition, formation, release and identification of exosomes are intro⁃ duced in detail. The research status of exosomes from different stem cell sources in tissue engineering and regenerative medicine is described, and their broad application prospects are discussed.
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@#Objective: To investigate the effects of ezrin enhancer knockout on ezrin gene expression, cell proliferation and migration of human esophageal carcinoma Eca-109 cells. @*@#Methods: The CRISPR/Cas9 recombinant plasmids targeting upstream/downstream of human ezrin enhancer were co-transfected into human esophageal carcinoma Eca-109 cells, and the cell line Eca-C2 with ezrin enhancer knockout was screened by purinomycin. Then the expression levels of ezrin mRNAand protein in Eca-C2 cells were detected by Real-time quantitative PCR (qPCR) and Western blotting, respectively; The expression levels of MAPK-pathway-related proteins were detected by protein array technology; and the effects of ezrin enhancer knockout on the proliferation and migration of Eca-C2 cells were analyzed by WST-1 method and wound-healing assay, respectively. @*@# Results:The human esophageal carcinoma cell line Eca-C2 with stable ezrin enhancer knockout was established successfully. Compared with control cells, the mRNA and protein expressions of ezrin in Eca-C2 cells were significantly reduced (all P<0.05).Among the 17 detected MAPK pathway related proteins in Eca-C2 cells, 9 proteins (AKT, CREB, GSK3b, MKK6, mTOR, P38, P53, P70S6K and RSK1) were down-regulated, and the cell proliferation and migration were significantly inhibited (all P<0.05).@*@# Conclusion: ezrin enhancer knockout can significantly inhibit the cell proliferation and migration of human esophageal carcinoma Eca-109 cells.
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@#Derived from the neural crest, dental stem cells (DSCs) are a population of cells with the characteristics of mesenchymal stem-ness, which under certain appropriate conditions can differentiate into multiple cells such as osteocytes, chondrocytes, hepatocyte and neuronal-like cells. DSCs are consist of odontogenic stem cells mainly include dental pulp stem cells, periodontal ligament stem cells, stem cells from deciduous teeth, stem cells from apical papilla, as well as dental follicle progenitor cells. DSCs have been widely used in the field of regenerative medicine research and preclinical research, including nervous system diseases, oral diseases, immune diseases, heart and lung diseases, etc. This review will focus on the storage of DSCs and current translational and clinical studies regarding DSCs in tissue regeneration.