• 대한의용생체공학회:의공학회지
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• 제15권3호
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• pp.259-264
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• 1994

혈액으로부터 헤파린을 선택적으로 제거하기 위하여 cellulose 기질에 양이온 고분자인 poly(allylamine)(PALA)을 새로운 방법으로 고정화하여 헤파린 제거제를 제조한 다음 in vitro 헤파린 용액내에서 흡착실험을 행하여, 미처리 cellulose control과의 흡착능을 비교하였다. 제조된 헤파린 제거제와 미처리 cellulose의 표면적은 각각 1.36 및 $2.56m^2$/g로 개질처리된 경우의 표면적이 약 1/2로 감소하였다. 또한 제조된 헤파린 제거제에 흡착된 헤파린의 양은 개질 방법에 따라 0.16~$0.03{\mu} g$/$cm^2$로 미처리 celluose($0.03{\mu} g$/$cm^2$)보다 월등히 우수한 헤파린 흡착능을 나타내었다.

• The Journal of Advanced Prosthodontics
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• 제3권3호
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• pp.145-151
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• 2011

PURPOSE. This study was performed to investigate the ability of recombinant human-bone morphogenic protein-2 immobilized on a heparin-grafted bone substrate to enhance the osteoblastic functions. MATERIALS AND METHODS. The Bio-$Oss^{(R)}$, not coated with any material, was used as a control group. In rhBMP-2-Bio-$Oss^{(R)}$ group, rhBMP-2 was coated with Bio-$Oss^{(R)}$ using only deep and dry methods (50 ng/mL, 24 h). In heparinized rhBMP-2-Bio-$Oss^{(R)}$ group, dopamine was anchored to the surface of Bio-$Oss^{(R)}$, and coated with heparin. rhBMP-2 was immobilized onto the heparinized- Bio-$Oss^{(R)}$ surface. The release kinetics of the rhBMP-2-Bio-$Oss^{(R)}$ and heparinized rhBMP-2-Bio-$Oss^{(R)}$ were analyzed using an enzyme-linked immunosorbent assay. The biological activities of the MG63 cells on the three groups were investigated via cytotoxicity assay, cell proliferation assay, alkaline phosphatase (ALP) measurement, and calcium deposition determination. Statistical comparisons were carried out by one-way ANOVA test. Differences were considered statistically significant at $^*$P<.05 and $^{**}$P<.001. RESULTS. The heparinized rhBMP-2-Bio-$Oss^{(R)}$ showed more sustained release compared to the rhBMP-2-Bio-$Oss^{(R)}$ over an extended time. In the measurement of the ALP activity, the heparinized group showed a significantly higher ALP activity when compared with the non-heparinized groups (P<.05). The MG63 cells cultivated in the group with rhBMP-2 showed increased calcium deposition, and the MG63 cells from the heparinized group increased more than those that were cultivated in the non-heparinized groups. CONCLUSION. Heparin increased the rhBMP-2 release amount and made sustained release possible, and heparinized Bio-$Oss^{(R)}$ with rhBMP-2 successfully improved the osteoblastic functions.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1998년도 추계학술대회
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• pp.227-228
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• 1998

Lumbrokinase, potent fibrinolytic enzyme purified from earthworm, was immobilized onto polyurethane valves using photoreaction, photoreactive polyallyl-amino as a photoreactive linker. For evaluation of blood compatibility, lumbrokinase immobilized polymer valves were assembled into the total artificial heart (TAH). This TAH was implanted to 60kg healthy lamb for 1-3 days with the cardiac output 5 L/min. In the control lamb, the valves were untreated, in ore other, only valves on the right were treated, and in the remaining animal, only those on the left. To facilitate the thrombus formation, low doses of heparin were administered. For evaluation of the immobilized lumbrokinase, thrombus formation, proteolytic and fibrinolytic activity was measured. This data shows that lumbrokinase-treated polyurethane valves lead to decreased thrombus formation in vivo, and that their biocompatibility is therefore higher than that of untreated valves.

• Journal of Microbiology and Biotechnology
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• 제21권6호
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• pp.659-664
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• 2011

Staphylococcus aureus (SA) bacteremia is associated with high mortality, and often results in metastatic infections. The methicillin-resistant SA (MRSA) is an urgent health care issue, as nosocomial infections with these bacteria represent limited treatment alternatives. Samples of whole blood containing challenge inoculums of SA and MRSA strains were passed through columns packed with surfaceheparinized polyethylene beads. The bound bacteria were eluted and quantitatively determined by culturing and by real-time PCR. Significant amounts of both SA and MRSA adhered to the heparinized beads (more than 65% of inoculated bacteria). After rinsing with buffer at high ionic strength, viable bacteria or bacterial DNA were eluted from the columns, indicating that the binding was specific. The conclusions that can be made from these experiments are that, as earlier reported in the literature, the high affinity of SA to heparin is retained in whole blood, and MRSA in whole blood binds to heparin with similar or higher affinity than SA. It should be possible to lower the amount of SA and/or MRSA from the blood of infected patients to levels that could be taken care of by the immune system. In previous studies, we have shown that passing blood from septic patients over beads coated with end-point-attached, biologically active heparin is a useful technique for regulating the levels of heparinbinding cytokine. These findings in combination with the present findings indicate the possibility of creating an apheresis technology for treatment of sepsis caused by SA and/or MRSA.

• The Journal of Advanced Prosthodontics
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• 제3권3호
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• pp.152-160
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• 2011

PURPOSE. This study was to investigate the effects of recombinant human platelet-derived growth factor (rhPDGF-BB) and heparin to titanium surfaces for enhancement of osteoblastic functions and inhibition of inflammation activity. MATERIALS AND METHODS. The anodized titanium discs, not coated with any material, were used as a control group. In heparinized-Ti group, dopamine was anchored to the surface of Ti substrates, and coated with heparin. In PDGF-Ti group, rhPDGF-BB was immobilized onto heparinized Ti surface. The surface morphologies were investigated by the scanning electron microscope in each group. The release kinetics of rhPDGF-BB were analyzed, and cytotoxicity tests for each group were conducted. The biocompatibilities were characterized by measuring cell proliferation, alkaline phosphatase activity, and calcium deposition using MG-63 cells. Statistical comparisons were carried out by one-way ANOVA tests. Differences were considered statistically significant at $^*$P<.05 and $^{**}$P<.001. RESULTS. The combination of rhPDGF-BB and heparin stimulated alkaline phosphatase activity and OCN mRNA expression in osteoblastic cells ($^*$P<.05 and $^{**}$P<.001). MG-63 cells grown on PDGF-Ti had significantly higher amounts of calcium deposition than those grown on anodized Ti ($^{**}$ P<.001). Heparinized Ti was more anti-inflammatory compared to anodized Ti, when exposed to lipopolysaccharide using the transcript levels of TNF-${\alpha}$ and IL-6 of proinflammatory cytokine ($^*$P<.05 and $^{**}$P<.001). CONCLUSION. The result of this study demonstrated that the incorporation of rhPDGF-BB and heparin onto Ti surface enhanced osteoblastic functions and inhibited inflammation.

• 대한치과보철학회지
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• 제51권4호
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• pp.307-314
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• 2013

연구 목적: 본 연구는 골형성단백질의 서방출을 위해 헤파린과 골형성단백질 (rhBMP-2)을 화학적으로 고정시킨 양극산화 티타늄 임플란트가 골 결손부에서 임플란트 주변의 수직적 골증대에 미치는 효과를 방사선학적으로 평가하고자 시행되었다. 연구 재료 및 방법: Pure-Titanium을 사용하여 길이 7.0 mm, 직경 3.5 mm의 실험용 임플란트 18개를 제작하였다. 모든 임플란트를 양극산화처리 하였고, 플랫폼 하방 2.5 mm에 식립 기준선을 표시하였다. rhBMP-2가 코팅되지 않은 임플란트 집단을 대조군으로, dip and dry 방법으로 rhBMP-2를 물리적 흡착시킨 집단을 BMP군, 3,4-dihydroxyphenylalanine(DOPA)-heparin을 이식하고 rhBMP-2를 화학적으로 고정시킨 집단을 Hep-BMP군으로 설정하였다. 각군별6개씩의 임플란트를 3마리의 비글견 양측 하악에 한쪽에 3개씩 총 18개를 치조정 상방으로 2.5 mm 노출시켜 식립하였다. 식립 직후와 4주, 8주에 식립부위의 방사선학적 검사가 시행되었고, 각 시기별, 각 군별 임플란트의 근원심 변연골의 수직적 재생량에 대한 평균값과 표준편차를 얻었다. Kruskal-Wallis test와 Mann-Whitney U test를 이용하여 4주, 8주에서 대조군과 실험군들의 차이를 비교 분석하고, 유의 수준5%에서 통계적으로 검정하였다. 결과:방사선학적 관찰 결과 임플란트 근원심 변연골 재생량(평균값 ${\pm}$ 표준편차)은 4주에 대조군은 $0.09{\pm}0.22mm$, BMP군은 $1.02{\pm}0.72mm$, Hep-BMP군은 $1.29{\pm}0.51mm$ 였으며, 8주에서는 각각 $0.11{\pm}1.26mm$, $1.11{\pm}0.58mm$, $1.59{\pm}0.79mm$였다. 두 실험군 모두 4주와 8주에서 대조군과 비교 시 유의한 수직적 골증대를 나타냈으나(P<.05), Hep-BMP군과BMP군의 비교에서는 유의한 변연골 재생량 차이를 보이지 않았다(P>.05). 결론: 골형성단백질을 물리적으로 흡착시키거나 서방출 위해 헤파린을 이용하여 화학적으로 고정시킨 양극산화 임플란트 표면은 모두 골 결손부에서 임플란트 주변골의 수직적 증대에 효과적이었다. 그러나 방사선학적 관찰의 한계 내에서 골형성단백질의 이 두가지 적용방법간에는 수직적 골증대량에 유의한 차이가 없었다.