• Journal of radiological science and technology
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• v.25 no.2
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• pp.77-82
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• 2002

It is well known that X-irradiation affects on maturing process of differentiated chondrocytes. Nevertheless, It has been remained elusively whether X-irradiation affects the process of differentiation of mesenchymal cells which differentiate into chondrocyte, fibroblast, or muscle cells. In this study, we examined the effect of X-irradiation (with 1 to 10 Gy) on chondrogenesis using the mesenchymal cells of chick limb bud. Our results show that X-irradiation dose-dependently inhibited chondrogenesis. This result suggests that immature chondroblast-like mesenchymal cells are sensitive to X-irradiation. Moreover, X-irradiation affects not only maturing process of chondrocytes, but also inhibits the chondrogenesis. Taken together, we demonstrate that the whole process of differentiation of mature chondrocytes from mesenchymal cells is affected by X-irradiation and undifferentiated cells were more affected by X-irradiation than mature cells.

• Journal of Chest Surgery
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• v.54 no.5
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• pp.356-360
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• 2021

Background: Primary pulmonary malignant mesenchymal tumors are rare, constituting only 0.4% of all lung cancers. Since sarcomas are chemo/radio-resistant, surgical resection is the optimal treatment choice for patients with suitable medical conditions and tumor stage. In the present study, we analyzed the surgical outcomes and survival of primary pulmonary malignant mesenchymal tumors treated surgically. Methods: We retrospectively examined the records of patients with primary pulmonary malignant mesenchymal tumors who underwent surgical resection at our department between January 2010 and December 2020. Patient data were analyzed according to age, sex, tumor grade and stage, resection completeness, surgical type, and tumor histopathology. Results: Twenty patients were included in the study. There were 13 men (65%) and 7 women (35%). The median survival rate was 36 months (range, 19-53 months), and the 5-year overall survival rate was 37%. Unfavorable prognostic factors for overall survival included parietal pleural invasion (p=0.02), high tumor grade (p=0.02), advanced tumor stage (p=0.02), and extensive parenchymal resection (pneumonectomy and bilobectomy, p=0.01). The median length of disease-free survival was 31 months (interquartile range, 21-41 months), and the 5-year disease-free survival rate was 32%. The most unfavorable prognostic factors for recurrence were parietal pleural invasion (p=0.02), high tumor grade (p=0.01), and tumors requiring lung resection with chest wall resection (p=0.02). Conclusion: Primary malignant mesenchymal lung tumors are aggressive and have a high mortality rate. However, acceptable overall and disease-free survival rates can be obtained with surgical therapy.

• Molecules and Cells
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• v.38 no.7
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• pp.643-650
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• 2015

The use of conditioned medium from mesenchymal stem cells may be a feasible approach for regeneration of bone defects through secretion of various components of mesenchymal stem cells such as cytokines, chemokines, and growth factors. Mesenchymal stem cells secrete and accumulate multiple factors in conditioned medium under specific physiological conditions. In this study, we investigated whether the conditioned medium collected under hypoxic condition could effectively influence bone regeneration through enhanced migration and adhesion of endogenous mesenchymal stem cells. Cell migration and adhesion abilities were increased through overexpression of intercellular adhesion molecule-1 in hypoxic conditioned medium treated group. Intercellular adhesion molecule-1 was upregulated by microRNA-221 in mesenchymal stem cells because microRNAs are key regulators of various biological functions via gene expression. To investigate the effects in vivo, evaluation of bone regeneration by computed tomography and histological assays revealed that osteogenesis was enhanced in the hypoxic conditioned medium group relative to the other groups. These results suggest that behavioral changes of endogenous mesenchymal stem cells through microRNA-221 targeted-intercellular adhesion molecule-1 expression under hypoxic conditions may be a potential treatment for patients with bone defects.

• Proceedings of the KSLP Conference
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• 2015.03a
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• pp.19-19
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• 2015

• Journal of Life Science
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• v.23 no.8
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• pp.970-977
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• 2013

The epithelial-to-mesenchymal transition (EMT) plays an essential role in embryogenesis and is involved in tumor metastasis and invasion; it significantly contributes to tumor progression and aggressiveness. The EMT is characterized by a loss of epithelial cell polarity as a result of the reduced expression of epithelial E-cadherin, a hallmark of the EMT, and the acquisition of mesenchymal-like cell morphology. Reactive oxygen species (ROS) such as $O_2{^-}$, $H_2O_2$, and $OH^-$ have been demonstrated to induce the EMT; although Snail is involved in ROS-induced EMT by transcriptionally repressing E-cadherin, its mechanism is not fully understood. In this study, we examined the effects of early growth response 1 (Egr-1) overexpression in noninvasive breast tumor cell line MCF-7 cells. Upon Egr-1 overexpression, MCF-7 cells lost epithelial cell polarity and became more spindle-shaped, indicating that Egr-1 may induce EMT. We found that Snail is implicated in Egr-1 induced EMT. We further demonstrate that the Egr-1-Snail axis is activated by ROS and plays a critical role(s) in ROS-induced EMT.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.5
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• pp.405-418
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• 2007

Mesenchymal stem cells(MSCs) have been though to be multipotent cells that can replicate that have the potential to differentiate into lineages of mesenchymal tissue including the bone, cartilage, fat, tendon, muscle, and marrow stroma. Especially, scaffolds to support cell-based tissue engineering are critical determinants of clinical efforts to regenerate and repair the body. Selection of a matrix carrier imvolves consideration of the matrix's role as a scaffold for physical support and host tissue integration as well as its ability to support of synergize the osteoinductive program of the implanted mesenchymal stem cell. The aim of this study is to evaluate the effect of autobone and Bio-$Oss^{(R)}$ to adherent mesenchymal stem cells as scaffolds on sinus augmentation with fibrin glue mixture in a rabbit model. 16 New Zealand White rabbits were divided randomly into 4 groups based on their time of sacrifice(1, 2, 4 and 8 weeks). First, mesenchymal stem cells were isolated from iliac crest marrow of rabbits and expanded in vitro. Cell culture was performed in accordance with the technique described by Tsutsumi et al. In the present study, the animals were sacrificed at 1, 2, 4 and 8 weeks after transplantation, and the bone formation ability of each sides was evaluated clinically, radiologically, histologically and histomorphologically. According to the histological observations, autobone scaffolds group showed integrated graft bone with host bone from sinus wall. At 2 and 4 weeks, it showed active newly formed bone and neovascularization. At 8 weeks, lamellae bone was observed in sinus graft material area. Radiologically, autobone with stem cell showed more radiopaque than Bio-$Oss^{(R)}$ scaffolds group. there were significant differences in bone volume between 4 and 8 weeks(p<0.05).

• Journal of Periodontal and Implant Science
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• v.37 no.3
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• pp.479-488
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• 2007

In spite of the attention given to the study of mesenchymal stem cells derived periodontal ligament (PDL), there is a lack of information about canine PDL cells. In this study, we characterized canine PDL cells to clarify their stem cell properties, including self renewal, proliferate rate, stem cell markers and multipotency. PDL cells were obtained from extracted premolars of canines, following a colony forming assay and proliferation rate of sub-confluent cultures of cells for self-renewal, immunostaining for STRO-1 and CD146/MUC18 and a differentiation assay for multipotency. Canine PDL cells formed single-cells colonies and 25% of the PDL cells displayed positive staining for BrdU. The cells expressed the mesenchymal stem-cell markers, STRO-1 and CD146/MUC18. Under defined culture conditions, the cells differentiated into osteoblasts and adipocytes, but the cells didn't differentiated into chondrocytes. The findings of this study indicated that the canine PDL cells possess crucial stem cells properties, such as self-renewal and multipotency, and express the mesenchymal stem cell markers on their surface. The isolation and characterization of canine PDL cells makes it feasible to pursue preclinical models of periodontal regeneration in canine.

• Development and Reproduction
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• v.21 no.1
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• pp.1-10
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• 2017

The use of human mesenchymal stem cells (hMSCs) in cell-based therapy has attracted extensive interest in the field of regenerative medicine, and it shows applications to numerous incurable diseases. hMSCs show several superior properties for therapeutic use compared to other types of stem cells. Different cell types are discussed in terms of their advantages and disadvantages, with focus on the characteristics of hMSCs. hMSCs can proliferate readily and produce differentiated cells that can substitute for the targeted affected tissue. To maximize the therapeutic effects of hMSCs, a substantial number of these cells are essential, requiring extensive ex vivo cell expansion. However, hMSCs have a limited lifespan in an in vitro culture condition. The senescence of hMSCs is a double-edged sword from the viewpoint of clinical applications. Although their limited cell proliferation potency protects them from malignant transformation after transplantation, senescence can alter various cell functions including proliferation, differentiation, and migration, that are essential for their therapeutic efficacy. Numerous trials to overcome the limited lifespan of mesenchymal stem cells are discussed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.1
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• pp.11-18
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• 2008

Human bone marrow mesenchymal stem cells are thought to be multipotent cells, which are present in adult marrow, that can replicate as undifferentiated cells and that have the potential to differentiate to lineages of mesenchymal tissues, including bone, cartilage, fat, tenden, muscle, and marrow stroma. Cells that have the characteristics of human mesenchymal stem cells could be isolated from marrow aspirates of human and animals. This study was designed to identify and characterize genes specifically expressed by osteogenic supplements -treated cells by suppression subtractive hybridization(SSH) method. The results were as follows: 1. 2 genes were upregulated genes in osteogenic diffeentiation of hMSCs, which is further proved by Northern blot analysis. 2. IGFBP-2 has been identified playing an important role in bone formation. 3. HF1 was also upregulated during osteogenic differentiation, but its role in bone formation is not clear yet.

• Journal of Pharmaceutical Investigation
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• v.40 no.6
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• pp.333-337
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• 2010

Combining cell- and gene-based therapy is a promising therapeutic strategy in regenerative medicine. The aim of this study was to develop genetically modified mesenchymal stem cell (MSC) aggregates using a poly(ethylene glycol) (PEG) hydrogel micro-well array technique. Stable PEG hydrogel micro-well arrays with diameters of 200 to $500\;{\mu}m$ were fabricated and used to generate genetically engineered MSC aggregates. Rat bone marrow-derived MSCs were transfected with a green fluorescent protein (GFP) plasmid as a reporter gene, and aggregated by culturing in the PEG hydrogel micro-well arrays. The resultant cell aggregates had a mean diameter of less than $200\;{\mu}m$, and maintained the mesenchymal phenotype even after genetic modification and cell aggregation. Transplantation of MSC aggregates that are genetically modified to express therapeutic or cell-survival genes may be a potential therapeutic approach for regenerative medicine.