• Journal of Periodontal and Implant Science
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• v.39 no.2
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• pp.119-128
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• 2009

Purpose: The aim of this study was to evaluate the stemness of cells from canine dental tissues and bone marrow. Methods: Canine periodontal ligament stem cells (PDLSC), alveolar bone stem cells (ABSC) and bone marrow stem cells(BMSC) were isolated and cultured. Cell differentiations (osteogenic, adipogenic and chondrogenic) and surface antigens (CD146, STRO-1, CD44, CD90, CD45, CD34) were evaluated in vitro. The cells were transplanted into the subcutaneous space of nude mice to assess capacity for ectopic bone formation at 8 weeks after implantation. Results: PDLSC, ABSC and BMSC differentiated into osteoblasts, adipocytes and chondrocytes under defined condition. The cells expressed the mesenchymal stem cell markers differently. When transplanted into athymic nude mice, these three kinds of cells with hydroxyapatite /${\beta}$- tricalcium phosphate (HA/TCP) carrier showed ectopic bone formation. Conclusions: This study demonstrated that canine dental stem cells have stemness like bone marrow stem cells. Transplantation of these cells might be used as a therapeutic approach for dental stem cell-mediated periodontal tissue regeneration.

• The Korean Journal of Zoology
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• v.31 no.1
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• pp.49-55
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• 1988

A few SV4O-transformed human cells such as SV8O are potentially tumorigenic but rejected by athymic hosts. However, one cell line in this group (W118IVA-2) is known to be fully tumorigenic. Two clones were obtained after the injection of W118IVA-2, of which NW1SC1-1 was tumorigenic but NW18C1-2 was not in nude mice. As examined by Southern blot analysis, NW18C1-1 appears to contain more copy number of SV40 sequences than NW18C1-2 does. However, it was unable to demonstrate that this difference elicits the tumorigenicity in NW18C1-1 but not in NW18C1-2. Therefore, the latter clone was tested if it expresses SV40 early genes to produce large T as well as small t antigens using indirect immunofluorescent assay and immunoprecipitation. In addition, mouse NIH3T3 cells were transfected with the cellular DNA of NW1SC1-2 as well as that of NW18C1-1 to examine if the viral genomes in the clones can make the nontransformed cells to acquire malignant growth potential in vivo. The transformed cells expressed large T antigen and became tumorigenic. Thus, the transforming functions of NW1SC1-2 cell appers to be intact. These results clearly suggest that the inability of NW18C1-2 cell to form tumor in nude mice is not because they are inherently nontumorigenic. However, the possibility that the interaction of SV40 with its host differs in these clones can not he ruled out.

• Polymer(Korea)
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• v.32 no.1
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• pp.26-30
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• 2008

This study was designed to investigate the effect of hybridization of synthetic/natural materials for annulus fibrosus (AF) tissue regeneration in vitro and in vivo. The synthetic/natural hybrid scaffolds were prepared using PLGA (poly (lactic-co-glycolic) acid), SIS (small intestinal submucosa) and DBP (demineralized bone particles). PLGA, PLGA/SIS(20%), PLGA/DBP(20%) and PLGA/SIS (10%)/DBP (10%) scaffold were manufactured by solvent casting/salt leaching method. Compressive strength was measured. Rabbit AF cells were isolated, cultured and seeded into experimental groups. Hydroxyproline production and DNA quantity of AP cells on each scaffold was measured at 2, 4 and 6 weeks after in vitro culture. Cell-scaffold composites were implanted subcutaneously into athymic mice. After 1,4 and 6 weeks postoperatively, specimens were taken and H&E, Safranin-O and type I collagen staining were carried out concerning formation of cartilagenous tissue. In vitro PLGA/SIS scaffold was evaluated for total collagen content (bydroryproline/DNA content) and PLGA scaffold was evaluated for compressive strength.

• Journal of Biomedical Engineering Research
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• v.15 no.1
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• pp.41-50
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• 1994

The chemotherapy using macromolecules, i.e., monoclonal antibodies loaded with anticancer agents hasn't been successful in delivering therapeutic amount of the conjugates. The comprehensive evaluation of mass transfer factors in tumor is prerequisite for the development of the effective chemotherapy. Characterization of neuroblastoma implanted in immunosuppressed athymic nude rats was performed. Its growth kinetics, glucose metabolic rate (GMR) were measured along with the interstitial fluid pressure (IFP), blood perfusion rate (BPR) and pH distribution throughtout the tumor radius. Volume doubling time and GMR were 8.1 days(SD 0.44 day), 23.53 mg/min/100 g(SD 3.54 mg/min/100 g), respectively. The IFP in tumor center was increased with tumor volume, and approached to 3 mmHg (SD 2.6 mmHg) when the tumor was 3 cm high. The radial distribution of IFP, BPR and pH in 2 cm high tumors showed that BPR and pH were decreased, while IFP was increased as the ~ensors moved toward the tumor center. The elevated IFP, decreased BPR and pH in tumor center suggested that the delivery of conjugates might be increased by properly manipulating mass transfer factors.

• Polymer(Korea)
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• v.28 no.5
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• pp.382-390
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• 2004

One of the significant natural bioactive materials is demineralized bone particle (DBP) whose has a powerful induce. of new bone growth. In this study, we developed the DBP loaded poly-lactide (PLA) and poly(L-lactide-co-glycolide) (PLGA) scaffolds for the possibility of the application of the tissue engineered bone. PLA/DBP and PLGA/DBP scaffolds were prepared by solvent casting/salt leaching method and were characterized by porosimeter, scanning electron microscopy. BMSCs were stimulated by osteogenic medium and characterized by histological stained Wright-Giemsa, Alizarin red, von Kossa, and alkaline phosphate activity (ALP). DBP impregnated scaffolds with BMSCs were implanted into the back of athymic nude mouse to observe the effect of DBP on the osteoinduction compared with control scaffolds. It can be observed that the porosity was above $90.2\%$ and the pore size was above 69.1$\mu$m. BMSCs could be differentiated into osteoprogenitor cells as result of wright-giemsa, alizarin red, von Kossa and ALP staining. In in vivo study, we could observed calcification region in PLA/DBP and PLGA/DBP groups, but calcification did not occur almost in control scaffolds. From these results, it seems that DBP as well as BMSCs play an important role for bone induction in PLA/DBP and PLGA/DBP scaffolds.

• Polymer(Korea)
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• v.32 no.6
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• pp.516-522
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• 2008

Biodegradable polymers have been used extensively as scaffolding materials to regenerate new tissues and the ingrowth of tissue have been reported to be dependent directly of the porosity, pore diameter, pore shape, and porous structure of the scaffold. In this study, porous poly (L-lactide-co-glycolide) (PLGA) scaffolds with five different pore sizes were fabricated to investigate the effect of pore sizes for AF tissue regeneration. Cellular viability and proliferation were assayed by MTT test. Hydroxyproline/DNA content of AF cells on each scaffold was measured. sGAG analyses were performed at each time point of 2 and 6 weeks. Scaffold seeded AF cells were implanted into the back of athymic nude mouse to observe the difference of formation of disc-like tissue depending on pore size in vivo. We confirmed that scaffold with $180{\sim}250{\mu}m$ pores displayed high cell viability in vitro and produced higher ECM than scaffold with other pore sizes in vivo.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.4
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• pp.825-829
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• 2006

Rhus verniciflua Stokes has been used for treatment of blood stasis and abdominal mass in Oriental medicine. Rhus verniciflua Stokes has been experimentally reported to exert antioxidant, antiproliferative, antithrombotic and apoptotic activities. In the present study, the antiangiogenic and in vivo antitumor activities of aqueous extract of processed Rhus verniciflua Stokes (Nexia) by heat were examined to elucidate its anticancer mechanism. Nexia showed weak cytotoxiicty against human umbilical vein endothelial cells (HUVEC) and Lewis lung carcinoma cells (LLC) with IC50 of${\sim}200\;{\mu}g/ml\;and\;>200\;{\mu}g/ml$, respectively. Nexia significantly inhibited the proliferation and migratory activity in vascular endothelial growth factor(VEGF) treated HUVEC. Furthermore, Nexia effectively suppressed the tumor volume in A549 nonsmall lung cancer bearing athymic nude mice, CanN. Cg-Foxn 1nu/CrljBgi up to 40.7% as well as tumor weight incised from LLC cells innoculated into the flank of C57BL/6 mice up to -50% compared with untreated control at a dose of 300 mg/kg. Taken together, these results suggest that processed Rhus verniciflua Stokes may inhibit the growth of Lewis lung carcinoma cells partly via inhibition of angiogenesis and can be potently applied to angiogenesis dependent cancers. However, it still needs a further research on molecular mechanism, angiogenesis animal study and clinical trial in future.

• The Journal of Korean Obstetrics and Gynecology
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• v.37 no.1
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• pp.1-22
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• 2024

목 적: 본 연구의 목적은 유방암 세포(MCF-7) 이식 누드 마우스 모델을 이용하여 육종용 열수 추출물의 면역활성 효과를 통한 항암 활성을 체계적으로 평가하는 것이다. 육종용 열수 추출물은 유방암 치료제로 자주 사용되는 대표적인 경구용 항암제인 tamoxifen 경구 투여군과 비교하여 분석 연구하였다. 방 법: 총 110마리의 6주령 암컷 누드 마우스를 준비하여, 7일간 적응 후 체중이 일정한 마우스를 선정하여 우측 둔부 피하부위에 MCF-7 세포를 이식하였다. 종양세포 이식을 한 지 20일 후, 종양 크기 및 체중을 기준으로 그룹 당 8마리씩 본 실험에 사용하였다. MCF-7 이종 이식 21일 후부터 매일 1회씩 35일간 육종용 열수 추출물을 10 ml/kg의 용량(400, 200 및 100 mg/kg)으로 경구 투여하였으며, tamoxifen 역시 10 ml/kg의 용량(20 mg/kg)으로 경구 투여하였고, 정상 및 종양 이식 매체 대조군에서는 멸균증류수만 종양 이식 21일 후부터 동일한 방법으로 35일간 경구 투여 하였다. 결 과: 본 실험의 결과, MCF-7 세포 이식을 함으로써 현저한 비장 및 하악하 림프절 무게, 혈중 IFN-γ의 함량, IL-1β 및 IL-10의 함량, 비장내 TNF-α, 비장세포 및 복강 대식구의 활성의 감소가 관찰되었고, 비장 및 하악하 림프절의 림프구 감소에 의한 조직병리학적 위축 또한 관찰되었다. 그리고 체중 및 증체량의 감소 역시 관찰되었으며, 혈중 IL-6 함량의 증가, 난소 주위의 지방 무게의 감소 및 조직병리학적으로 난소 주위의 축적 지방 조직 위축 현상이 인정되어, 종양 이식 후에 전형적인 종양과 관련된 면역억제와 악액질 현상이 유발된 것으로 판단되었다. 한편 육종용 열수 추출물 400, 200 및 100 mg/kg 경구 투여군에서는 종양 이식 대조군에 비해 유의성 있는 현저한 항암활성이 투여 용량 의존적으로 관찰되었다. 또한 tamoxifen 20 mg/kg 경구 투여군에서는 종양 관련 악액질 소견이 오히려 악화되는 반면, 육종용 열수 추출물 경구 투여군에서는 면역활성 및 악액질 억제 효과가 관찰되었다. 결 론: 본 연구 결과, 육종용 열수 추출물의 적절한 경구 투여는 심각한 부작용 없이, 종양 관련 악액질 소견을 포함하여, 효과적인 유방암 치료 수단을 제공할 수 있을 것으로 기대된다.

• Journal of radiological science and technology
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• v.34 no.3
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• pp.239-244
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• 2011

In this study, we evaluated diffusion weighted imaging (DWI) to investigate whether the DWI parameters can predict characteristic parameters on pathologic specimens of tumor or not. CFPAC-1 was injected subcutaneously on the back flank of athymic nude mice (n=13) then two tumors were initiated on each mouse (2${\times}$13=26 tumors). The mice were sacrificed to make specimen immediately after initial MR imaging then were compared with the MR image. A dedicated high-field (7T) small-animal MR scanner was used for image acquisitions. A T1 and T2 weighted axial image using RARE technique was acquired to measure the T2 values and tumor size. DWI MR was performed for calculating ADC values. To evaluate tumor cellularity and determine the levels of MVD, tumor cells were excised and processed for H-E staining and immunostaining using CD31. T2 values and ADC values were computed and analyzed for each half of the tumors and compared to the correlated specimens slide. Median ADC within each half of mass was compared to the cellularity and MVD in the correlated area of pathologic slide. The mean of ADC value is $0.7327{\times}10^{-3}$ $mm^2/s$ and standard deviation is $0.1075{\times}10^{-3}$ $mm^2/s$. There is a linear relationship between ADC value and tumor necrosis (R2=0.697, p< 0.001). DW image parameters including the ADC values can be utilized as surrogate markers to assess intratumoral neoangiogenesis and change of the internal structure of tumor cells.

• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.106-111
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• 1998

This study has been focused on both estrogenic and proliferating activity of genistein (GEN) and bisphenol A (BPA). GEN and BPA enhance the proliferation of estrogen-dependent MCF-7 human breast cancer cells at concentrations as low as 100 nM of GEN and 8 ng/ml of BP A achieving similar effect to that of estradiol at 1 nM. Expression of the estrogen responsive gene, pS2 was also induced in MCF-7 cells by treatment with genistein at dose as low as 1 nM and BPA at dose as low as 4 ng/ml. Using 21 day-old ovariectomized nude mice, we examined end-bud formation and mammary gland development after treatment with bisphenol A or genistein. Compared with untreated control, mammary gland development and end-bud formation were significantly increased in mice fed genistein or bisphenol A (p<0.05). Taken together, it is concluded that GEN and BP A can act as an estrogen agonist resulting in cell proliferation and induction of the estrogen responsive pS2 gene in MCF-7 cells in vitro and in athymic mice in vivo, respectively. Therefore, it is suggested that GEN and BP A might modulate human endocrine system and these compounds might be considered as a endocrine modulator at the low levels of doses.