• 한국환경성돌연변이발암원학회지
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• 제18권2호
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• pp.93-97
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• 1998

The results of chromosome aberration test in mammalian cells in culture (Chinese hamster lung fibroblast cells) showed no induction of structural and numerical aberrations by antifungal agents of YH1715 series regardless of metabolic activation. While positive control group (mitomycin C and benzo(a)pyrene) showed structural chromosome aberrations of 37% and 23%, respectively. The in vivo induction of micronuclei was measured in polychromatic erythrocytes in bone marrow of male ddY mouse given YH1715R and YH1729R at 1, 0.5, 0.25 g/kg by p.o. once. After 24 hours, animals were sacrificed and evaluated 40 the incidence of micronucleated polychromatic erythrocytes in whole erythrocytes. Although a positive response for induction of micronuclei in animals treated with mitomycin C demonstrated the sensitivity of the test system for detection of a chemical clastogen, YH1715R did not induce micronuclei in bone marrow of ddY male mice but induced cytotoxicity to bone marrow cells at the highest concentration (1 g/kg, p〈0.05), and YH1729R induced micronuclei in bone marrow of ddY male mice dose dependently (p<0.05) but did not induce cytotoxicity to bone marrow cells.

• Carbon letters
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• 제13권3호
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• pp.139-150
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• 2012

Poly-L-lactic acid (PLLA), PLLA/hydroxyapatite (HA), PLLA/multiwalled carbon nanotubes (MWNTs)/HA, PLLA/trifluoroethanol (TFE), PLLA/gelatin, and carbon nanofibers (CNFs)/${\beta}$-tricalcium phosphate (${\beta}$-TCP) composite membranes (scaffolds) were fabricated by electrospinning and their morphologies, and mechanical properties were characterized for use in bone tissue regeneration/guided tissue regeneration. MWNTs and HA nanoparticles were well distributed in the membranes and the degradation characteristics were improved. PLLA/MWNTs/HA membranes enhanced the adhesion and proliferation of periodontal ligament cells (PDLCs) by 30% and inhibited the adhesion of gingival epithelial cells by 30%. Osteoblast-like MG-63 cells on the randomly fiber oriented PLLA/TEF membrane showed irregular forms, while the cells exhibited shuttle-like shapes on the parallel fiber oriented membrane. Classical supersaturated simulated body fluids were modified by $CO_2$ bubbling and applied to promote the biomineralization of the PLLA/gelatin membrane; this resulted in predictions of bone bonding bioactivity of the substrates. The ${\beta}$-TCP membranes exhibit good biocompatibility, have an effect on PDLC growth comparable to that of pure CNF membrane, and can be applied as scaffolds for bone tissue regeneration.

• Biomaterials and Biomechanics in Bioengineering
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• 제1권3호
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• pp.151-162
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• 2014

Genetically-modified mesenchymal stem cells (GM-MSCs) have emerged as promising therapeutic tools for orthopedic degenerative diseases. GM-MSCs have been widely reported that they are able to increase bone and cartilage tissue regeneration not only by secreting transgene products such as growth factors in a long-term manner, also by inducing MSCs into tissue-specific cells. For example, MSCs modified with BMP-2 gene increased secretion of BMP-2 protein resulting in enhancement of bone regeneration, while MSCs with TGF-b gene did cartilage regeneration. In this review, we introduce several growth factors for gene delivery to MSCs and strategies for bone and cartilage tissue regeneration using GM-MSCs. Furthermore, we describe strategies for strengthening GM-MSCs to more intensively induce tissue regeneration by co-delivery system of multiple genes.

• Journal of Ginseng Research
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• 제44권6호
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• pp.823-832
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• 2020

Background: The formation of a nanotube layer on a titanium nanotube (N-Ti) plate facilitates an active reaction between bone cells and the material surface via efficient delivery of the surface materials of the dental implant into the tissues. Studies have reported that Korean Red Ginseng extracts (KRGEs) are involved in a variety of pharmacological activities: we investigated whether implantation with a KRGE-loaded N-Ti miniimplant affects osteogenesis and osseointegration. Methods: KRGE-loaded nanotubes were constructed by fabrication on pure Ti via anodization, and MC3T3-E1 cells were cultured on the N-Ti. N-Ti implants were subsequently placed on a rat's edentulous mandibular site. New bone formation and bone mineral density were measured to analyze osteogenesis and osseointegration. Results: KRGE-loaded N-Ti significantly increased the proliferation and differentiation of MC3T3-E1 cells compared with cells on pure Ti without any KRGE loading. After 1-4 weeks, the periimplant tissue in the edentulous mandibular of the healed rat showed a remarkable increase in new bone formation and bone mineral density. In addition, high levels of the bone morphogenesis protein-2 and bone morphogenesis protein-7, besides collagen, were expressed in the periimplant tissues. Conclusion: Our findings suggest that KRGE-induced osteogenesis and osseointegration around the miniimplant may facilitate the clinical application of dental implants.

• Journal of Acupuncture Research
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• 제24권5호
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• pp.13-22
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• 2007

Objectives : The differentiation of osteoblasts is controlled by various growth factors and matrix protein expressed in bone. The aim of this study was to investigate the effects of many herbs medicine(KHBJs) for bone healing that induces osteogenic activity in human osteoblast-like SaOS-2 cells. Methods : The osteogenic effects of KHBJs were evaluated by using cell proliferation(WST-8) assay, alkaline phosphatase(ALP) activity assay, colorimetric analysis of vascular endothelial growth factor(VEGF) expression in human osteoblast like SaOS-2 cell. Also, osteogenic activity of KHBJ fractions(KHBJB and KHBJR) by activity guided fractionation were evaluated. Results : About 7 KHBJs had effect on the proliferation of osteoblast like SaOS-2 cells, and dose-dependently increased alkaline phosphatase(ALP) activity. KHBJs markedly increased expression for VEGF. Fractionated KHBJs(KHBJB or KHBJR) not enhanced more than KHBJs on osteogenic activity in SaOS-2 cells. Conclusions: This study found that 7 KHBJs had effect on proliferation, ALP activity, and VEGF expression in osteoblast like SaOS-2 cells. These results propose that KHBJs can play an important role in osteoblastic bone formation, and may possibly lead to the development of bone-forming drugs.

• 대한미생물학회지
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• 제10권1호
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• pp.1-8
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• 1975

Despite a number of recent studies on appendix its function appears to remain unknown. The present studies were undertaken in order to extend and confirm the previous studies concerning the role of appendix in immune response. An early hemagglutinin response of mercaptoethanol sensitive antibody(IgM antibody) in rabbit injected intravenously(i.v.) with 200mcg of bovine gamma globulin(BGG) was abolished by lethal whole body irradiation(900 r), but preserved in animals whose appendix and bone marrow were shielded during irradiation. Late formation of mercaptoethanol resistant antibody(IgG antibody) and the development of memory in bone marrow shielded animals were not affected by irradiation of the appendix. Formation of either IgM or IgG antibody to sheep red blood cells(SRBC) injected i.v. as determined by direct plaque forming cell(DPFC) technique in spleen were effectively abolished by appendectomy, thymectomy, or both followed by irradiation. When bone marrow was shielded in combination with autologous appendix reconstitution, DPFC response was about 5 times greater than the sum of two. Lysed appendix cells failed to restore the response. Lethally irradiated rabbits restored with combination of autologous appendix and thymus cells showed DPFC responses which were essentially normal. Three pools of appendix were obtained by manual separation technique and were stimulated with soluble concanavalin A(Con A), phytohemagglutinin-P(PHA) and pokeweed mitogen(PWM). Rabbit appendix cells responded to Con A, PHA and PWM. Cells of thymus dependent area(TDA) of the appendix were relatively enriched in their response to T cell mitogens compared to dome and follicle cells. The PHA/Con A responsive ratio of appenix TDA subpopulation was high, indicating that Con A responsive cells have a wider distribution among appendix. This finding showed that interfollicular area of the appendix is thymus-dependent. The present studies confirmed other evidence that the rabbit appendix cells itself are unable to form antibody and T lymphocytes in appendix TDA may be heterogenous, and that the appendix cells are synergistic with either bone marrow or thymus cells in the early hemagglutinin on splenic antibody response to BGG or SRBC.

• Journal of Periodontal and Implant Science
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• 제41권4호
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• pp.192-200
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• 2011

Purpose: The aim of this study is to compare the gene expression profile in mesenchymal stem cells derived from dental tissues and bone marrow for characterization of dental stem cells. Methods: We employed GeneChip analysis to the expression levels of approximately 32,321 kinds of transcripts in 5 samples of bone-marrow-derived mesenchymal stem cells (BMSCs) (n=1), periodontal ligament stem cells (PDLSCs) (n=2), and dental pulp stem cells (DPSCs) (n=2). Each cell was sorted by a FACS Vantage Sorter using immunocytochemical staining of the early mesenchymal stem cell surface marker STRO-1 before the microarray analysis. Results: We identified 379 up-regulated and 133 down-regulated transcripts in BMSCs, 68 up-regulated and 64 down-regulated transcripts in PDLSCs, and 218 up-regulated and 231 down-regulated transcripts in DPSCs. In addition, anatomical structure development and anatomical structure morphogenesis gene ontology (GO) terms were over-represented in all three different mesenchymal stem cells and GO terms related to blood vessels, and neurons were over-represented only in DPSCs. Conclusions: This study demonstrated the genome-wide gene expression patterns of STRO-$1^+$ mesenchymal stem cells derived from dental tissues and bone marrow. The differences among the expression profiles of BMSCs, PDLSCs, and DPSCs were shown, and 999 candidate genes were found to be definitely up- or down-regulated. In addition, GOstat analyses of regulated gene products provided over-represented GO classes. These data provide a first step for discovering molecules key to the characteristics of dental stem cells.

• 한국한의학연구원논문집
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• 제10권1호
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• pp.127-135
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• 2004

Hematopoietic stem cells in bone marrow form all kinds of blood cells. In traditional medicine, functions of bone marrow cells are very similar to those of Essence(精) which is a fundamental factor of physical development and reproduction. Our experiment examined the effect of deer blood on aplastic anemia induced mouse using cyclophosphamide 150 mg/kg i.p injection before experiment and then another cyclophosphamide 120 mg/kg i.p injection on day 10. Then we administrated dried deer blood in distilled water for 5 days, 9 days and 10 days. We examined blood and marrow samples. In results, deer blood showed a trend of effectiveness on recovery of red blood cells and erythropoietin although they were not statistical significant. And deer blood did not show changes in CD34.

• Archives of Plastic Surgery
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• 제34권2호
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• pp.141-148
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• 2007

Purpose: The object of this study was to evaluate the development of continuous osteogenic differentiation and bone formation after the subcutaneous implantation of the tissue-engineered bone, in vitro. Methods: Human adipose-derived stem cells were obtained by proteolytic digestion of liposuction aspirates. Adipose-derived stem cells were seeded in PLGA scaffolds after being labeled with PKH26 and cultured in osteogenic differentiation media for 1 month. The PLGA scaffolds with osteogenic stimulated adipose-derived stem cells were implanted in subcutaneous layer of four nude mice. Osteogenesis was assessed by RT-PCR for mRNA of osteopontin and bone sialoprotein(BSP), and immunohistochemistry for osteocalcin, and von Kossa staining for calcification of extracellular matrix at 1 and 2 months. Results: Implanted PLGA scaffold with adipose-derived stem cells were well vascularized, and PLGA scaffolds degraded and were substituted by host tissues. The mRNA of osteopontin and BSP was detected by RT-PCR in both osteogenic stimulation group and also osteocalcin was detected by immunohistochemistry at osteogenic stimulation 1 and 2 months, but no calcified extracellular deposit in von Kossa stain was found in all groups. Conclusion: In vivo, it could also maintain the characteristics of osteogenic differentiation that adipose-derived stem cells within PLGA scaffold after stimulation of osteogenic differentiation in vitro, but there were not normal bone formation in subcutaneous area. Another important factor to consider is in vivo, heterologous environment would have negative effect on bone formation as.[p1]

• IMMUNE NETWORK
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• 제1권3호
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• pp.230-235
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• 2001

Background: Finding of the regulation of various gene expression by cytokine including $IFN-{\gamma}$ in hematopoietic stem cell will light up the understanding of pathogenesis of aplastic anemia in various aspects. To study on aplastic anemia, however, we have to circumvent the difficulty of directly obtaining bone marrow stem cells from the patient. Therefore, we tried to find out a cell can replace the bone marrow stem cells for study on cell signaling pathway and regulation of gene expression by $IFN-{\gamma}$. Materials and Methods: HL-60 cells, of 20 ng/mL of $IFN-{\gamma}$. Total RNA was isolated from the cells and RT-PCR of the indoleamine 2,3-dioxygenase (IDO), $IFN-{\gamma}$, TNF-${\alpha}$, $MIP-1{\alpha}$, and $TGF-{\beta}2$ was carried out for the estimation of the gene expression. Results: $IFN-{\gamma}$ induced IDO gene expression of mononuclear cells from umbilical cord blood showed similar pattern as compared to that of bone marrow. Whether $INF-{\gamma}$ was treated or not, $TNF-{\alpha}$ was expressed in both mononuclear cells from umbilical cord blood and bone marrow. However, HL-60 cells showed different expression patterns. HL-60 cells would express neither IDO nor $TNF-{\alpha}$ even under the culture with 20ng/mL of $IFN-{\gamma}$. Conclusion: Our results showed bone marrow can be replaced with mononuclear cells from umbilical cord blood in the study on the relation between aplastic anemia and $IFN-{\gamma}$ including $IFN-{\gamma}$ cell signaling pathway.