• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.80-88
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• 1996

The aim of the present investigation was to see the effect of combined use of PDGF BB and IGF -1 on the guided tissue regeneration(GTR) using barrier membrane in the treatment of human furcation involvement. Twelve patients with initially diagnosed as having moderate to advanced adult periodontitis with mandibular class II buccal furcation defects have been wer selected. Initial scaling and root planing has been performed and baseline data consisting of probing depths and attachment levels have been recorded prior to surgical procedures. The GTR procedures using either barrier membrane(control : ePTFE) alone or together with the application of PDGF - BB and IGF -l(experimental : ePTFE+PDGF/IGF) have been done under the routine guidelines. During the surgery, the distance from CEJ either to the bottom of the bone defects(CEJ - BD) or to the bone crest(CEJ-BC) were measured. Horizontal distance to the deepest area in the furcal defects were measured from the reference line connection the most prominent bony walls of the two buccal roots. 6 months following the GTR therapy, all the measurements were made repeatedly. The probing attachment gain of the experimental and the control grous were 2.14mm and l.07mm, respectively with no statically significnant difference. Amont of vertical bone fill in the experimental and the control groups were 2.43mm and 2.29mm, rexpectively. Amonut of horizontal bone fill were 2.86mm in the experimental group and 2.17mm in the control group, respectively. However, there were no significant differences in the amount of bone fill(both vertical and horizontal)between the two groups.

• Journal of Periodontal and Implant Science
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• v.26 no.3
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• pp.771-778
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• 1996

The assessment of alveolar bone changes on dental radiographs to indicate progression of periodontal diseases or healing response to therapy is routine procedure. However, the diagnostic accuracy in detecting small alveolar bone changes is very limited. Recently, guided bone regeneration therapy is popular, but the quantification of new bone is somewhat difficult with conventional evaluation method. To quantificate the amount of new bone, various evaluating methods have been introduced including histomorphometry, radiomorphometry, biochemical analysis, X-ray probe microanalysis, scanning electron microscope backscatter method. In this study, guided bone regeneration using resorbable membrane with & without PDGF-BB is quatificated through histomorphmetry to evaluate the efficacy of histomorphometric analysis. 4 beagle dogs and 8 Sprague-Dawley rats were selected as experimental animals. In beagle dog experiment, $4{\times}4mm$ Class II defects were created in maxillary both second premolars, and biodegradable membrane containing PDGF-BB(experimental group) were covered over one defect, and same membrane without PDGF-BB(control group) were covered over the other defect. At 2 weeks, 5 weeks after surgery, each beagle dogs were sacrificed, and the tissues were treated by undecalcified fixation. In Sprague-Dawley rat experiment, 5mm round defect were created in temporal bone, the same membranes were covered on the defects. At 1 week, 2 weeks after surgery, each rats were sacrificed, and undecalcified fixation were taken. After grinding tissue specimen, we analyse them histomorphometrically using image analysis system. In beagle dog 2 weeks specimens, new bone formation area were $0.03123mm^2$ in experimental group,and $0.03012mm^2$ in control group. At 5 weeks specimens, $0.15324mm^2$ in experimental group, and $0.09123mm^2$ in control group. In Sprague-Dawley rat specimens, new bone fomation area were $0.20448mm^2$ in 1 week experimental group, $0.03604mm^2$ in 1 week control group. At 2 weeks specimens, $0.46349mm^2$ in experimental group, $0.17741mm^2$ in control group. The results indicated that histomorphometric analysis of new bone formation using image analysis system is very effective quantification method to evaluate the efficacy of treatment modalities.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.2
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• pp.113-122
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• 2007

Purpose: Platelet-rich plasma (PRP) is known to accelerate and/or enhance hard and soft tissue healing and regeneration. As such, PRP has been used in various clinical fields of surgery. Recently there have been several attempts to use PRP in the field of tissue engineering. However, some controversies still exist on exact mechanism and benefits of PRP. Therefore various animal experiments are necessary to reveal the effect of the PRP. However, even if animal experiment is performed, the efficacy of the experiment could not be validated due to absence of an animal PRP model. The purpose of this study is to establish rat PRP model by comparing several PRP fabricating methods, and to assay growth factor concentration in the PRP. Materials and methods: Rat blood samples were collected from nine SD rat (body weight: 600-800g). PRP was prepared using three different PRP fabricating methods according to previously reported literatures. (Method 1: 800 rpm, 15 minute, single centrifuge; Method 2: 1000 rpm, 10 minute, double centrifuge; Method 3: 3000 rpm, 4min and 2500 rpm, 8 min, double centrifuge). Platelet counts were evaluated in an automated machine before and after PRP fabrications. In terms of growth factor assay, prepared PRP were activated with 100 unit thrombin and 10% calcium chloride. Growth factor (PDGF-BB, VEGF) concentrations on incubation time were determined by sandwich-ELISA technique. Results: An average of 3ml (via infraorbital venous plexus) to 15ml (via celiac axis) the rat blood could be collected. By using Method 3 (3000 rpm, 4 min and 2500 rpm, 8 min, double centrifugation), around 1.5ml of PRP could be prepared. This method allowed us to concentrate platelet 3.77-fold on average. PDGF-BB concentration (mean, 1942.10 pg/ml after 1 hour incubation) and VEGF concentration (mean, 952.71 pg/ml after 1 hour incubation) in activated PRP were higher than those in untreated blood. Also PDGF-BB showed constant concentration during 4-hour incubation, while VEGF concentration was decreased after 1 hour. Conclusion: Total 11,000 g minute separation and condensation double centrifuge method can produce efficient platelet-rich plasma. Platelet-rich plasma activated with thrombin has showed higher concentrations of growth factors such as PDGF-BB and VEGF, compared to the control group. Platelet-rich plasma model in a rat model was confirmed in this study.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.3
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• pp.177-183
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• 2010

Tetrahydrobiopterin (BH4), an essential cofactor for nitric oxide synthase (NOS) activity, is known to play important roles in modulating both NO and superoxide production during vascular diseases such as atherosclerosis. However, the role of BH4 in functions of vascular smooth muscle cells is not fully known. In this study, we tested the effects of BH4 and dihydrobiopterin (BH2), a BH4 precursor, on migration and proliferation in response to platelet-derived growth factor-BB (PDGF-BB) in rat aortic smooth muscle cells (RASMCs). Cell migration and proliferation were measured using a Boyden chamber and a 5-bromo-2'-deoxyuridine incorporation assay, respectively, and these results were confirmed with an ex vivo aortic sprout assay. Cell viability was examined by 2,3-bis [2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide assays. BH4 and BH2 decreased PDGF-BBinduced cell migration and proliferation in a dose-dependent manner. The inhibition of cell migration and proliferation by BH4 and BH2 was not affected by pretreatment with $N^G$-nitro-L-arginine methyl ester, a NOS inhibitor. Moreover, the sprout outgrowth formation of aortic rings induced by PDGF-BB was inhibited by BH4 and BH2. Cell viability was not inhibited by BH4 and BH2 treatment. The present results suggest that BH4 and BH2 may inhibit PDGF-stimulated RASMC migration and proliferation via the NOS-independent pathway. Therefore, BH4 and its derivative could be useful for the development of a candidate molecule with an NO-independent anti-atherosclerotic function.

• Journal of Periodontal and Implant Science
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• v.27 no.4
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• pp.785-804
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• 1997

It was well known that calcium sulfate was biocompatible, resorbed rapidly in the body, had potential as a good barrier membrane. Platelet-derived growth factor(PDGF) was one of polypeptide growth factor that had been reported as a biological mediator which regulates activities of wound healing process including the cell proliferation, migration and metabolism. The purpose of this study was to evaluate the effects of a combination of calcium sulfate and PDGF on periodontal ligament cells in vitro to use as a regeneration promoting agent of periodontal tissue. Human periodontal ligament cells were prepared from the premolar tooth extracted for the orthodontic treatment. Cells were cultured in ${\alpha}-MEM$ contained with 20% FBS, at the $37^{\circ}C$, 100% of humidity, 5% $Co_2$ incubator. Cells were inoculated and cultured into 96 well culture plate with $1{\times}10^4cells/well$ of ${\alpha}-MEM$ for 1 day. After discarding the medium, those cells were cultured in ${\alpha}-MEM$ contained with 10% FBS alone(control group), in calcium sulfate(calcium sulfate group), in calcium sulfate treated with 15ng/ml of PDGF-BB(calcium sulfate+PDGF group), in ${\alpha}-MEM$ contained with 10% FBS treated with 15ng/ml of PDGF-BB(PDGF group) for 1, 2, 3 day respectively. And then each group was characterized by examining of the cell counting, MTT assay, collagen synthesis. The results were as follows. 1. In the analysis of cell proliferation by cell counting, both calcium sulfate group and calcium sulfate plus PDGF group showed no stastically significant difference compared to control group, but there was stastically significant difference between PDGF group and calcium sulfate group at 1, 2 day(P<0.05). 2. In the analysis of cell proliferation by MTT assay in calcium sulfate extracts, both calcium sulfate group and calcium sulfate plus PDGF group showed no stastically significant difference compared to control group, but there was stastically significant difference between PDGF group and calcium sulfate group at 2, 3 day, and between calcium sulfate plus PDGF group and calcium sulfate group at 2 day(P

• Journal of Periodontal and Implant Science
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• v.29 no.4
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• pp.785-804
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• 1999

The cell activities of bone metabolism is affected by growth factor rather than by hormone. The affects of growth factors on the bone activity were observed using various culture methods. Platelet-derived growth factor(PDGF) is produced from the well differentiated bone cell. It stimulates cell mitosis, synthesizes collagen in bone tissue and plays a role in healing response. The purpose of this study is to evaluate the effects that PDGF has on the activity and the proliferation of osteoblast by measuring the activity of alkaline phosphatase, the growth formation of calcified nodules, and osteocalcin production. In this study, HOS and ROS 17/2.8 osteoblastic cell line was used, along with variable concentrations of PDGF the were measured with osteoblastic proliferation. The cell proliferation of HOS and ROS 17/2.8 cells was stimulated dose- depentdently. Alakline phosphatase activity was significantly decreased by PDGF in osteoblastic cells. A number of small calcified nodules were observed in HOS cell treated with low concentrations(0.1, 0.4 ng/ml) of PDGF-BB and no significant difference from control group was found. High concentrations(10, 50 ng/ml) of PDGF suppressed calcified nodule formation. And osteocalcin production was inhibited with PDGF. These results suggest that PDGF stimulates the osteoblastic proliferation, whereas suppresses the individual cellular functions.

• Proceedings of the PSK Conference
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• 2002.04a
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• pp.177.2-178
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• 2002

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2002.05a
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• pp.79-79
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• 2002

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.1
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• pp.44-47
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• 2000

Cell growth and DNA synthesis were studied from a cultured early- and late- pas- sage mouse aorta smooth muscle cell (MASMC) because the proliferation of vascular smooth muscle cell (VSMC) is a key factor in development of atherosclerosis. In this study, the cells were cultured in fetal bovine serum (FBS) and stimulated by growth factors such as thrombin and platelet-derived growth factor-BB (PDGF-BB). Compared to the number of early-passage MASMC (passage 3 to 9) the number of late-passage MASMC (passage 30 to 40) in a normal serum state was increased 2 fold at Day 1, 3 and 6 in culture, respectively. Incorporation of $[^3H]$ thymidine into DNA induced by serum, PDGF and thrombin in late-passage MASMC was greater than those in early-passage MASMC. We also examined whether intracellular zinc levels would be an aging factor or not. The intracellular zinc level in early- and late-passage MASMC was monitored by using the zinc probe dye N-(6-methoxy-8-quinolyl)-p-toluenesulfonamide. It is interested that late-passage MASMC increased the intracellular fluorescence level of zinc, more than the early passage MASMC did. The alterations of intracellular zinc level occur concurrently with changes in MASMC proliferation rate during aging. This data suggest that the age-associated changes in zinc concentrations may provide a new in vitro model for the study of smooth muscle cell differentiation.

• Clinical and Experimental Pediatrics
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• v.51 no.8
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• pp.879-885
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• 2008

Purpose : The human lung fibroblast may act as an immunomodulatory cell by providing pro-inflammatory cytokines and chemokines, which are important in airway remodeling. Vascular endothelial growth factor (VEGF) induces mucosal edema and angiogenesis. Thymus and activation regulated chemokine (TARC) induces selective migration of T helper 2 cells. We investigated whether human lung fibroblasts produced VEGF and TARC, and the effects were augmented with the co-culture of fibroblasts and human bronchial smooth muscle cells (HBSMC), and whether dexamethasone can inhibit the proliferation and the release of VEGF in lung fibroblasts. Methods : Human lung fibroblasts were cultured with and without HBSMC, growth-arrested in serum-deprived medium, and pretreated with dexamethasone for 16 hours. After 24-hour stimulation with platelet derived growth factor-BB (PDGF-BB) and/or transforming growth factor-${\beta}$ (TGF-${\beta}$), culture supernatant was harvested for assays of VEGF and TARC. Cell proliferation was assayed using BrdU cell proliferation ELISA kit. Results : 1) The release of VEGF was significantly increased after stimulation with TGF-${\beta}$, and its release was augmented when co-stimulated with PDGF and TGF-${\beta}$. 2) VEGF release induced by PDGF or TGF-${\beta}$ was inhibited by dexamethasone. 3) There was no synergistic effect on the release of VEGF when human lung fibroblasts were co-cultured with HBSMC. 4) Dexamethasone did not suppress human lung fibroblasts proliferations. 5) Neither TGF-${\beta}$ nor PDGF induced TARC release from lung fibroblasts. Conclusion : Human lung fibroblasts may modulate airway remodeling by release of VEGF, but they have no synergistic effects when co-cultured with HBSMC. Dexamethasone suppresses VEGF release, not proliferation of lung fibroblast.