• Journal of Biomedical Engineering Research
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• v.15 no.3
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• pp.259-264
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• 1994

Heparin binders (Cell-PALA) used for selective heparin removal from blood, were prepared by immobilizing a cationic polymer, poly(allylamine) (PALA), onto cellulose substrate by a novel method. Their absorbing capacity for heparin was compared with untreated cellulose control using heparin solution in vitro. The surface areas of obtained heparin binders and untreated cellulose were 1.36 and ($2.56{\mu} g$/$cm^2$, respectively. The amount of bound heparin to PALA immobilized celluloses was determined to be 0.16 - $0.30{\mu}g$/cm, which is much higher than that of untreated cellulose ($0.03{\mu} g$/$cm^2$). These results suggest that Cell-PALA materials can be utilized for a heparin removal system.

• The Journal of Advanced Prosthodontics
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• v.3 no.3
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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.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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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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• v.21 no.6
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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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• v.3 no.3
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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.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.4
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• pp.307-314
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• 2013

Purpose: The aim of this study was to evaluate the effect of immobilization of the recombinant human bone morphogenetic protein 2 (rhBMP-2) on anodized titaum implants coated with heparin to enhance the vertical alveolar ridge augmentation in the supraalveolar peri-implant defect region. Materials and methods: 18 pure titanium implants (7.0 mm in length, 3.5 mm in diameter) were manufactured for this study. All implants were anodized and designed insertion reference line marked with laser at the apical 2.5 mm from the fixture platform. Implantation of 6 noncoated anodized implants (Control group), 6 anodized implants physically adsorbed with rhBMP-2 by dip and dry method (BMP group) and 6 anodized implants chemically immobilized 3,4-dihydroxyphenylalanine (DOPA)-heparin/ rhBMP-2 (Hep-BMP group) was performed in the both mandibular of three male adult beagle dogs using split-mouth design. Radiologic examinations were performed immediately after implant placement and 4 and 8 weeks after implant placement. The amount of mesio-distal bone augmentation was evaluated by measuring the vertical distance from the platform to the marginal bone. Statistical analysis was performed using one-way analysis of variance (SPSS version 18.0) and multiple comparison analysis of The Kruskal-Wallis test and the Mann-Whitney U test. Statistical significance was established at the 5% significant level. Results: At the 4 weeks vertical alveolar ridge augmentation of Control group, BMP group and Hep-BMP group is $0.09{\pm}0.22mm$, $1.02{\pm}0.72mm$, and $1.29{\pm}0.51mm$, At the 8 weeks $0.11{\pm}1.26mm$, $1.11{\pm}0.58mm$, $1.59{\pm}0.79mm$ according to radiographic observations. The two experimental groups showed a significantly increasing in vertical bone height compared with the control group (P<.05). However, there is no significant difference between the BMP group and Hep-BMP group (P>.05). Conclusion: The rhBMP-2 coated implants were enhanced the vertical bone growth in the supraalveolar peri-implant defect area. However, there is no significant difference between chemically and physically coating method.