• Polymer(Korea)
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• v.33 no.1
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• pp.84-90
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• 2009

Nitinol alloy (TiNi) has been widely used in vascular stents. To improve the blood compatibility of Nitinol alloy, its surface was chemically modified in this study. Nitinol was first coated with gold, then chemisorbed with L-cysteine (C/N), and followed by grafting of zwitter ionic poly(ethylene glycol) (PEG) (PEG-$N^+-SO_3{^-}$) to produce TiNi-C/N-PEG-N-S. The zwitter ionic PEG grafted on the Nitinol surface was identified by ATR-FTIR, ESCA and SEM. The hydrophilized surface was proven by the decrease of water contact angle. In addition, from the blood compatibility tests such as protein adsorption, platelet adhesion, and blood coagulation time, the surface-modified TiNi alloy exhibited a better blood compatibility as compared to the untreated Nitinol control. These results indicated a feasibility of synergistic effect of hydrophilic PEG and antithrombotic zwitter ion.

• Journal of Biomedical Engineering Research
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• v.25 no.1
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• pp.57-64
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• 2004

The non pulsation blood pump is divided into axial flow and centrifugal style according to the direction of inlet and outlet flow. An axial flow blood pump can be made smaller than a centrifugal blood pump because centrifugal pump's rpm is fewer than axial flow pump. Hemolysis is an important factor for the development of an axial flow blood pump. It is difficult to identify the areas where hemolysis occurs. Evaluation of hemolysis both in in-vitro and in-vivo test requires a long-time and more expensive. Computational fluid dynamics(CFD) analysis enables the engineer to predict hemolysis on a computer which just can get not only amount of htmolysis but also location of hemolysis. It takes shorter time and less expensive than in-vitro test. The purpose of this study is to git Computational fluid dynamics in axial flow pump and to verify the accuracy of prediction by the possibility of design comparing CFD results with in-vitro experimental results. Also, wish to figure out the correction method that can bring improvement in shape of axial flow blood pump using CFD analysis.

• Applied Biological Chemistry
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• v.39 no.2
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• pp.159-164
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• 1996

Screening of anticoagulant activity was conducted for the hot water extracts of 73 kinds of medicinal herbs, 41 kinds of Korean edible plants, and 5 kinds of sea weeds using plasma recalcification test(Tr). In the first screening several extracts of the plants, Alisma calndiculatum, Corydalis ternata Panax notoginseng, Allium sativum, Ganderma luidum, Codium fragile, showed high activities. When the plants were reextracted with various solvent conditions, acidic water extracts of Codium fragile showed the highest activity in APTT. A crude polysaccharide fraction(CF-1) was prepared by methanol reflux, ethanol precipitation, dialysis and Iyophilization of the acid extracts. CF-1 comprised 80.8% total sugar consisting of arabinose, galactose and glucose as the main monomers, 8.7% protein, and 13.3% sulfate. The anticoagulant activity of CF-1 was not changed by pronase digestion, but decreased by periodate oxidation, and this indicated that the anticoagulant activity was attributed to the polysaccharide portion.

• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1214-1222
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• 1998

Background : The intrapleural hypofibrinolysis is caused by mainly excessive concentration of pleural plasminogen activator inhibitor-1 antigen(PAI-1 Ag), which binds tissue type plasminogen activator. In pleural inflammation induced by sclerosing agents for pleurodesis, levels of pleural PAI-1 antigen increase in relation to decreasing D-dimer levels. It has been known that the pleural mesothelial cells have the capability of secreting PAI-1 Ag in response to inflammation in vivo. Therefore, we estimated whether pleural inflammation changes the balance between fibrinolytic and coagulative properties in exudative pleural effusions. Method : The thirty cases was included in our study. We determined the pleural levels of glucose, lactic dehydrogenase(LDH), pH and the counts of white blood cell(WBC), polymorpho leukocyte(PMN), lymphocyte as the parameters of pleural inflammation and cellular components of pleural fluid. The plasma level of fibrinogen in fluid and the neutrophil count in blood were determined. The levels of D-dimer, PAI-1 Ag and thrombinantithrombin III complex(TAT) were determined by ELISA(Behring, Marburg, Germany). Result : The causes of pleural effusion were as following : tuberculous in 14 cases, malignant in 10 cases and parapneumonic in 6 cases. The levels of pleural D-dimer, PAI-1 Ag and TAT was significantly higher than that of plasma(p<0..001). The severity of pleural inflammation did not correlated with pleural D-dimer, PAI-1 Ag, TAT and their plasma levels. But the level of pleural TAT correlated with pleural WBC and lymphocyte count. Conclusion : We found that the severity of pleural inflammations did not correlated with pleural D-dimer, PAI-1 Ag, TAT and the possibility of local production of PAI-1 antigen is present.

• Korean Journal of Microbiology
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• v.36 no.3
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• pp.216-220
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• 2000

Eighty-eight strain3 o~methicillin resistant Stopllylococcus awecis were Isolated from pus (64.7%); spuhm (26.2%), blood, fluid, andurine of 83 patients at Dong-A Hospital in P~~san to invesligate theil-coagulase typ- Ing, and multi-drug resistaut ppattems. The presence of niec A gene confe~~ing melhicillin resistance was tested by polymerase chain reaction (PCR) with uwo mec A gene specific primers using purified clromosonlal DNA as templates. DNA fragments of expected size wel-e detected frorn 86 strains, but not from two strains. !i coagulase typmg, the 86 isolates were assigned to 5 coagulase lypes, I, 11, lll. 1V, VI, VII, VIlI, but there was no isolate helong lo type V. The most abundant coagulase type was type TI(50 %), lollowed by type IV Rest ofthe coagulase types were ininor; ranging fmm 4.5 to 12.5 '% Most of the type I1 ~netlucillin resistant Stapl\ulcorneryiococcus nwem (MRSA) strams were isolated from the generd sulzely ward, but major strains of type IV were Isolated from the otorhinolq~ngology of the hospital's outpatient clinic center. All of the 88 st~nins were sensitive to vancomycin and teicoplanin, but 71 (81%) strains showed multi-drug resitant to penicillin, cephalotl~n, eiythroinycin, gentan~ycin, imipenem, clindamycin, ciprofloxacin and ooxacillin. Yo relationship was found between the antibiotic resistance pattems aud the coagulase typing patterns.

• Journal of Chest Surgery
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• v.35 no.3
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• pp.171-176
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• 2002

Background: Blood-foreign interaction cause activation of coagulation and inflammatory process that may lead to multiorgan dysfunction and determine the surgical outcomes. Of the methods for assessing the biocompatibility, the platelet adhesion study is considered as the most valuable evaluation step in blood-foreign interaction. As the most studies have used in-vitro or ex-vivo conditions, we have developed a technique of quantification for platelet adhesion on the blood contact surface by using in-vivo injection of radioactive platelets. Material and Method: A coupled bypass circuit was designed to connect the proximal and descending thoracic aorta in 6 piglets(20∼25 Kg). One side of the circuit tube was consisted of a heparin coated PVC tube(10mm in ID, n=6, Experimental group), and the other, a non-heparin coated PVC tube(10mm in ID, n=6, Control group). After cannulation, the blood was circulated through the circuit for 2 hours. Platelet concentrate was prepared from homologous pig blood 24 hours before the experiment. The platelet concentrate was incubated with Tc-99m-HMPAO for 30 min and then centrifuged for 10 min. The supernatant was discarded and the radio-labeling efficacy was measured. The radio-labeled platelet concentrate was mixed with the autologous plasma to make the volume 5 ml, and the mixture was injected intravenously into the experimental animal. After 2 hour circulation, 5 pieces of the specimen(10mm in length each) were obtained from each PVC tube. The radioisotopes were counted with a gamma counter(Cobra ll, Packard, USA), and the ratio of radioisotope count was compared between the control and experimental group. Result: The radioisotope count number was 537.3221.1 Ci/min in the control group and 311.1 184.5 Ci/min in the experimental group(p=0.0104). The ratio between the groups was 1 to 0.58 (p=0.004). Conclusion: In vivo quantification using technetium-99m-HMPAO labeled platelets is simple and reproducible in evaluating platelet adhesion on a foreign surface. We suggest this technique to be a useful tool for blood compatibility test.

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.516-521
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• 2006

The possibility of usage as cosmetic resource of the mycelial culture broth of P. japonica in the mixture of cucumber and grape extracts was investigated. In the effect of collagen synthesis promotion in human fibroblast cells, the culture broth of P. japonica of 0.1, 0.5 and 1.0% concentration increased the amount of collagen synthesis than that of control cells. The culture broth increased the SOD activity in the concentration dependant manner of 0.01% to 1.0% in the antioxydation activity test. About 90% of superoxide radical was eliminated by 0.5% concentration of the culture supernatant in the antioxydation test. Anticoagulant quercetin in the course of mycelial growth in the mixture of cucumber and grape extract was accumulated to 15 folds than that of pre-culture. In the skin safety test of the culture broth, there is no any skin damage signal in the tested 30 people. Taken together, we concluded that the culture broth of P. japonica in the mixture of grape and cucumber extracts can be used as a cosmetic resource.

• Journal of Life Science
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• v.26 no.3
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• pp.289-295
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• 2016

Sorbus commixta, a flowering plant in the Rosaceae family, is native to Japan and Ulleung Island, Korea. This plant is also called maga-mok or mai-mok in Korea because the bud of the stem has a similar shape to the teeth of a horse. In this study, hot water extracts from different parts of S. commixta, such as leaf, stem, and immature and mature fruits, were prepared, and their antithrombosis and antioxidant activities were evaluated. The extraction yield and pH of stem extracts were 3.99% and 5.5, respectively. The stem extracts contained 89.2 mg/g of total polyphenols and 28.3 mg/g of total flavonoids. The hot water extracts prepared from the leaf, stem, immature, and mature fruit of S. commixta exhibited no hemolytic activity against human red blood cells, up to a concentration of 0.5 mg/ml. In an anticoagulation assay, the stem extracts showed strong extension in thrombin, prothrombin, and activated partial thromboplastin times, whereas the other extracts had no anticoagulation activity. In a platelet aggregation inhibitory activity assay, all the extracts tested had no inhibitory activity against human platelets. With regard to antioxidation activity, the stem extracts showed stronger radical scavenging activity and reducing power activity than the other extracts. The calculated RC₅₀s, the concentration required for 50% radical scavenging activity, for DPPH anions, ABTS cations, and nitrite of the crude stem extracts were 119.7, 53.3, and 117.5 μg/ml, respectively, whereas they were 13.7, 5.2, and 14.9 μg/ml for DPPH anions, ABTS cations, and nitrite, respectively, for vitamin C. The results suggest that the stem extracts of S. commixta have strong potential for use as a novel resource for antithrombosis agents.

• Korean Journal of Microbiology
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• v.39 no.4
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• pp.242-247
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• 2003

Murine encephalomyocarditis virus (EMCV) has been used as a surrogate for hepatitis A virus (HAV) for the validation of virus removal and/or inactivation during the manufacturing process of biopharmaceuticals. Recently international regulation for the validation of HAV safety has been reinforced because of the reported cases of HAV transmission to hemophiliac patients who had received ntihemophilic factors prepared from human plasma. The purpose of the present study was to compare the resistance of HAV and EMCV to various viral inactivation processes and then to standardize the HAV validation method. HAV was more resistant than EMCV to pasteurization (60oC heat treatment for 10 hr), low pH incubation (pH 3.9 at 25oC for 14 days), 0.1 M NaOH treatment, and lyophilization. EMCV was completely inactivated to undetectable levels within 2 hr of pasteurization, however, HAV was completely inactivated to undetectable levels after 5 hr treatment. EMCV was completely inactivated to undetectable levels within 15 min of 0.1 M NaOH treatment, however, residual infectivity of HAV still remained even after 120 min of treatment. The log reduction factors achieved during low pH incubation were 1.63 for HAV and 3.84 for EMCV. Also the log reduction factors achieved during a lyophilization process of antihemophilic factor VIII were 1.21 for HAV and 4.57 for EMCV. These results indicate that HAV rather than EMCV should be used for the virus validation study and the validation results obtained using EMCV should be precisely reviewed.

• Journal of Chest Surgery
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• v.13 no.4
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• pp.356-363
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• 1980

Even now, the hemorrhagic syndrome after cardiac surgery with the aid or a pump oxygenator constitutes a significant problem. The purpose of this study is to postulate the possible causes of the bleeding after open hear surgery [OHS]. Fifteen consecutive OHS patients with various heart diseases were selected and platelet count, plasma fibrinogen, serum calcium level were observed pre-, intra- and post- operatively until 21 th postoperative day [POD]. The platelet count was significantly decreased with initiation of extracorporeal circulation [ECC] and continued to decrease slowly until cessation of ECC. Within 10 minutes after ECC the platelet count stared to increase. But it was significantly less than preoperative count until 5th POD. The peak count was found on 14th POD and the platelet count was gradually decreased. Plasma fibrinogen also decreased significantly during operation, but it recovered up to preoperative amount within 5 hours after termination of ECC. Thereafter it rapidly increased until 3rd POD when it reached its peak. From 3rd POD it showed slow downward slope until 21st POD, but it remained in significantly higher level than preoperative amount. Serum calcium levels showed minimum fluctuations during the whole course of study. Conclusively, the decrease in platelet count and fibrinogen amount may play a considerable role for the postoperative hemorrhage. But numerous other effects of ECC must be accounted for.