• 대한두경부종양학회:학술대회논문집
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• 1998.11a
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• pp.272.2-273
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• 1998

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.191.1-191.1
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• 2000

• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.150-156
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• 1999

The induction of proliferation of adult rat islets was investigated under various culture conditions. The islets were isolated from male Sprague-Dawley rats and subsequently embedded in collagen gels, which mimic the in vivo three-dimensional surroundings. During the culture period, the effects of heterologous serum (fetal bovine serum, FBS), epidermal growth factor (EGF), and retinoic acid (RA) on islet growth were examined with respect to the morphological and total DNA content changes. To investigate these changes at the cellular level, whole mount immunocytochemistry using specific antibodies for insulin and glucagon was performed. The results showed that (i) collagen gels as an extracellular matrix can maintain islets in a similar way to that in vivo, (ii) heterologous serum (FBS) had stimulatory effects on islet proliferation in a dose-dependent manner, (iii) RA had inhibitory effects on islet proliferation induced by the serum in a dose-dependent manner, (iv) EGF had weak inhibitory effects on islet proliferation induced by the serum except at the concentration of 10 nM where its effect was not significant, and (v) whole mount immunocytochemistry revealed that newly proliferated islet cells were mainly $\beta$-and $\alpha$-cells.

• Restorative Dentistry and Endodontics
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• v.21 no.2
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• pp.546-558
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• 1996

The purpose of this vitro study was to evaluate the activity of human pulpal cells to adhesive glycoprotein-coated and non-coated culture dishes. Well known adhesive glycoproteins were used, such as type I collagen, type IV collagen, fibronectin, laminin, and vitronectin. Each adhesive glycoproteins applied onto the culture dishes. In this study, the protein coated and non-coated dishes were classified as each groups. Human pulpal cells cultured onto each groups. After 24 hours, 48 hours, 72 hours incubation time, radioactivity with scintillation counter for evaluation of the activity of human pulpal cells. The results as follows : 1. After 24 hours incubation time, activity of human pulpal cells were best in laminin-coated group among groups. Then fibronectin, type I collagen group were better, and all proteins were better than control. 2. After 48 hours incubation time, activity of human pulpal cells were best in fibronectin coated group. 3. After 72 hours incubation time, activity of human pulpal cells were not significantly different in all of adhesive glycoproteins. 4. After 24 hours incubation time, activity of human pulpal cells were best in fibronectin and laminin coated group. Activity of human pulpal cells in type I collagen coated group were better after 24 hours incubation time then 48 hours incubation time.

• Journal of Life Science
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• v.16 no.6
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• pp.964-971
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• 2006

The cancer cells, characterized by local invasion and distant metastasis, are very dependant on extracellular matrix. The expression of matrix metalloproteinases (MMPs) has been implicated in the invasion and metastasis of cancer cells. Among the human MMPs, matirx metalloproteinase-2 (MMP-2) and matrix metalloproteinse-9 (MMP-9) are key enzymes that degrade type IV collagen of the matrix. Here, we studied the effect of disulfiram, an anti-tumor compound, on the suppression of the tumor invasion and the activity of MMP-2, MMP-9 in human osteosarcoma cells (U2OS). Disulfiram had the type IV collagenase inhibitory activity, the effect of inhibition of gene and protein expression, and these inhibitions were responsible for blocking invasion through cell mediated and non-cell mediated pathways. In conclusion, disulfiram inhibited expression of MMP-2 and MMP-9, and regulated the invasion of U2OS, Caki-1 and Caski. These observations raise the possibility of clinical therapeutic applications for disulfiram used as a potential inhibitor of cancer invasion.

• Journal of Periodontal and Implant Science
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• v.23 no.2
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• pp.219-227
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• 1993

The purpose of the present study was to evaluate the effects of 5% tetracycline(Tc) with or without citric acid on periodontally diseased root surfaces. Six single-rooted teeth extracted from one patient was selected and received thorough scaling and root planning, followed by saline irrigation. Each one tooth was divided into eight fragments with a thin separating disc. Total 48 fragments were prepared and setted into 4 groups for this study. Group I (control group)were treated with saline. Group II were treated with 5% Tc gel. Group III were treated with 33% citric acid-5% Tc gel. Group IV were treated with Tc solution. All the specimens are evaluated under Scanning Electron Microscope(SEM). Group I showed large amount of debris in spite of thorough scaling and root planing, but Group II, III & IV showed clean and soft root surface texture. In higher magnification(x3, 000), Group II, III & IV showed nunmerous dentinal tubules, especially Group IV showed collagen fibrils. In the present study, Tc gel and Tc gel with citric showed clinically successful result when treated on periodontally diseased root surface, in vitro.

• Journal of Korean Dental Science
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• v.14 no.1
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• pp.12-25
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• 2021

Purpose: (i) To evaluate the biologic properties of a bi-layered 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride-cross-linked collagen membrane (CCM) in vitro. (ii) To assess the efficacy of CCM for localized bone regeneration in vivo. Materials and Methods: Biodegradation of CCM compared to a native collagen membrane (NCM) was assessed in vitro. In vivo, twelve male New Zealand White rabbits were used. Four calvarial, circular defects (diameter 8 mm) were created in each animal. The sites were randomly allocated to i) CCM+biphasic calcium phosphate (BCP) (CCM-BCP group), ii) CCM alone (CCM), iii) BCP alone (BCP) and, iv) negative control (control). Animals were sacrificed at 2 (n=6) and 8 weeks (n=6). Outcome measures included: micro-computed tomography (μCT) analysis (total augmented volume [TAV], new bone volume) and histomorphometry (total augmented area [TAA], newly formed bone, remaining membrane thickness [RMT]). Result: CCM was more resistant to degradation than NCM. μCT analysis showed CCM-BCP (196.43±25.30 mm³) and BCP (206.23±39.13 mm³) groups had significantly (P<0.01) larger TAV than the control (149.72±12.28 mm³) after 8 weeks. Histomorphometrically, CCM-BCP group (17.75±5.97 mm²) had significantly (P<0.01) greater TAA compared to the CCM group (7.74±2.25 mm²) and the control (8.13±1.81 mm²) after 8 weeks. After 8 weeks, RMT was reduced by 67%. Conclusion: CCM can be a favorable choice of barrier membrane when performing guided bone regeneration (GBR) in localized bone defects. CCM has better resistance to degradation than the natural collagen membrane, in vitro. In vivo, CCM provides an advantageous integration of prolonged barrier function and biocompatibility for GBR.

• Clinics in Shoulder and Elbow
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• v.4 no.1
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• pp.1-12
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• 2001

Purpose: To evaluate the histologic effect(LM and EM findings)of nonablative LASER and thermal energy on knee joint capsule of rabbit. Material and Methods: The nonablative LASER and thermal energy was applied to the rabits(average age 36 weeks, weight 5 ㎏). There were divided into 4 groups with 6 rabbits in each. The group I received 6 watts of LASER, group Ⅱ 12 watts of LASER, group Ⅲ 60° of thermal energy, and group Ⅳ 70° of thermal energy. The histologic study included H-E, Massons trichrome stain and electron microscopy at immediate, 3 weeks and 6 weeks after operation. Results: The histologic finding in immediate after operation was shown a fibrous degeneration of collagen on all groups and related to the energy level. The histologic finding after 3 weeks showed fibrosis and this fibrosis related the level of energy. Especially the group IV was shown flattening of capsule and deep fibrosis. The histologic finding after 6 weeks was shown marked recovery of collagen arrangement and capillary proliferation in group Ⅰ,Ⅱ and Ⅲ. But in the group Ⅳ not recovered. Conclusion: The nonablative LASER or thermal energy can cause degeneration, fibrosis and contracture of joint capsular collagen.

• Biomedical Science Letters
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• v.12 no.2
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• pp.127-130
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• 2006

It is important to coordinated interaction among neurons, astrocytes and endothelial cells to maintain the function of brain. To study their regulatory mechanisms in vitro system, the co-culture system among the isolated cells from brain may be needed. However, the method for purifying brain microvascular endothelial cells (BMEC) far culture have not established yet. In this study, the proper culture methods of mice cells using two different strains, CD1 and C57BL6, to obtain the pure and plentiful endothelial cells were described. The flatted-round forms of CD1 endothelial cells grew on the collagen-IV coating plates, while the purified cells from C57 mice preferred type collagen-I dishes for their growth. Both cells displayed anti-PECAM-1 (CD31) and von Willebrand Factor immune-reactivity. These results indicated that different coating materials not only improve attachment of isolated cells but also promoting growth of cells, suggesting that this method of purifying murine Brain microvascular endothelial cells (BMEC) provides a suitable model to investigate blood-brain-barrier (BBB) properties within neurovascular unit in vitro.

• Journal of Nutrition and Health
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• v.53 no.1
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• pp.1-12
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• 2020

Purpose: Diabetic nephropathy is one of the most important diabetic complications prompted by chronic hyperglycemia, characterized by glomerulosclerosis, tubular fibrosis, and it eventually causes kidney failure. Nobiletin is a polymethoxyflavone present in tangerine and other citrus peels, and has anti-cancer and anti-inflammatory effects. This study investigated the effects of nobiletin on glomerular fibrosis through inhibition of the transforming growth factor (TGF)-β1-Src-caveolin-1 pathway. Methods: Human renal mesangial cells (HRMC) were incubated in media containing 33 mM glucose with or without 1-20 uM nobiletin for 3 day. The cellular expression levels of fibrogenic collagen IV, fibronectin, connective tissue growth factor (CTGF), TGF-β1, Src and caveolin-1 were all examined. In addition, TGF-β1, Src and caveolin-1 proteins were screened to reveal the relationship among TGF-β1-Src-caveolin-1 signaling in glomerular fibrosis. Results: High glucose promoted the production of collagen IV, fibronectin and CTGF in HRMC, which was inhibited in a dose dependent manner by 1-20 uM nobiletin. The Western blot data showed that high glucose elevated the expression of TGF-β1, Src, caveolin-1 and Rho GTPase. When nobiletin was treated to the HRMC exposed to high glucose, the expression of TGF-β1-Src-caveolin-1 was dampened. Finally, TGF-β1-Src-caveolin-1 signaling pathway was activated in high glucose-exposed HRMC, and such activation was encumbered by nobiletin. Conclusion: These result demonstrated that nobiletin blunted high glucose-induced extracellular matrix accumulation via inhibition of the TGF-β1-Src-caveolin-1 related intracellular signaling pathway. Nobiletin may be a potent renoprotective agent to counteract diabetes-associated glomerular fibrosis that leads to kidney failure.