• Biomolecules & Therapeutics
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• v.3 no.2
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• pp.165-170
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• 1995

The biochemical properties of the fibrinolytic protease of 50,800 Da isolated from the venom of Kgdistrodon blomhoffi brevicaudus were characterized. The enzyme hydrolyzed the carboxyl side of arginine in the synthetic chromogenic peptides, N-Benzoyl-Phe-Val-Arg-pNA and N-p-Tosyl-Gly-Pro-Arg-pNA, and the enzyme activity was inhibited by phenylmethylsulfonylfluoride indicating that the enzyme belongs to the serine protease family. The pretense showed maximum activity at pH 7.5 and inhibited by ZnCl$_2$, CuSO$_4$, but not by soybean trypsin inhibitor, pepstatin A, 2-mercaptoethanol and EDTA. The fm value determined with N-p-Tosyl-Gly-Pro-Arg-pNA was 0.2 mM. The thrombolytic activity of the purified enzyme was evaluated by platelet aggregation test in rabbits. While the platelet count ratio in blood of the rabbits injected with thrombin alone declined from 1.0 to 0.6 within 7 min and maintained around 0.6 for 24 hours thereafter, the ratio rapidly recovered from around 0.6 to 0.8 in 1 hr, to 1.0 in 24 hrs when the rabbits were sequentially treated with thrombin and the purified enzyme. The result showed that the serine protease from A. blomhoffi brevicoudus of 50,800 Da had a thrombolytic activity in vivo and the enzyme might be developed as a therapuetic agent for the treatment of thrombic disease.

• International Journal of Vascular Biomedical Engineering
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• v.4 no.2
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• pp.13-18
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• 2006

Direct injection of a fibrinolytic agent to the intra-arterial thrombosis may increase the effectiveness of thrombolysis by enhancing the permeation of thrombolytic agents into the blood clot. Permeation of fibrinolytic agents into a clot is influenced by the surface pressure, which is determined by the injection velocity of fibrinolytic agents. Computational fluid dynamic methods were used in order to predict clot lysis for different jet velocities and nozzle arrangements. Firstly, thrombolysis of a clot was mathematically modeled based on the pressure and lysis front velocity relationship. Direct injection of a thrombolytic agent increased the speed of thrombolysis significantly and the effectiveness was increased as the ejecting velocity increased. The nine nozzles model showed about 20% increase of the lysed volume, and the one and seventeen nozzles models did not show significant differences. Secondly, thrombolysis was modeled based on the enzyme transport and the fluid flow equations, and quasi steady numerical analysis was performed. Clot lysis efficiency was also increased as injection velocity increased.

• Journal of Biomedical Engineering Research
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• v.26 no.3
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• pp.157-161
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• 2005

Direct injection of a fibrinolytic agent to the intraarterial thrombosis may increase the effectiveness of thrombolysis by enhancing the permeation of thrombolytic agents into the blood clot. Permeation of fibrinolytic agents into a clot is influenced by the surface pressure, which is determined by the injection velocity of fibrinolytic agents. In order to calculate the pressure distribution on the clot surface for different jet velocities (1, 3, 5 m/sec) and nozzle arrangements (1, 9, 17 nozzles), computational fluid dynamic methods were used. Thrombolysis of a clot was mathematically modeled based on the pressure and lysis front velocity relationship. Direct injection of a thrombolytic agent increased the speed of thrombolysis significantly and the effectiveness was increased as the ejecting velocity increased. The nine nozzles model showed about $20\%$ increase of the lysed volume, and the one and seventeen nozzles models did not show significant differences. The wall shear stress decreased as the number of nozzles increased, and the wall shear stress in most vessel wall was lower than 25 Pa. The results implied that thrombolysis could be accelerated by direct injection of a drug with the moderate velocity without damaging the blood vessel wall.

• Archives of Pharmacal Research
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• v.21 no.3
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• pp.248-252
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• 1998

To prolong the biological half-life of streptokinase, a thrombolytic agent, streptokinase-bearing liposome with and distearolyphosphatidyl ethanolamine-N-poly (ethylene glycol) 2000 (DSPEPEG 2000) was prepared and evaluated. Streptokinase-bearing liposomes composed of distearolyphosphatidylcholine (DSPC), cholesterol and cholesterol-3-sulfate with DSPE-PEG 2000 was prepared by the freeze-thawing method and administered via femoral vein to rats (15000 IU/kg). The activity of streptokinase in plasma was determined by the method based on the amidolytic activity of streptokinase-plasminogen complex. Pharmacokinetic parameters of streptokinase incorporated in liposomes were compared with those of streptokinase alone. The $T_{1/2}$ and $AUC_\infty$ streptokinase incorporated in DSPC-PEG liposome increased 16.3- and 6.1-fold, respectively, compared with those of streptokinase alone. Streptokinase-bearing long-circulating liposome could increase the circulation time of streptokinase in blood and expect longer thrombolytic activity compared with streptokinase alone.

• Journal of Korean Neurosurgical Society
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• v.46 no.3
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• pp.226-231
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• 2009

Objective : We describe our clinical experiences and outcomes in patients who had thromboembolic complications occurring during endovascular treatment of intracerebral aneurysms with a review of the literature. The types of thromboembolic complications were divided and the treatment modalities for each type were described. Methods : Between August 2004 and March 2009 we performed endovascular embolization with Guglielmi detachable coils for 173 patients with 189 cerebral aneurysms, including ruptured and unruptured aneurysms at our hospital. Sixty-eight patients were males and 105 patients were females. The age of patients ranged from 22-82 years (average, 58.8 years). We retrospectively evaluated this group with regard to complication rates and outcomes. The types of thromboembolic complications were classified into the following three categories: mechanical obstruction, distal embolic stroke, and stent-induced complications, which corresponded to types I, II, and III, respectively. A comparison of the clinical results was made for each type of complication. Results : Only eight patients had a thromboembolic complication during or after a procedure (4.6%). Of the eight patients, two had a mechanical obstruction as the causative factor; the other three patients had distal embolic stroke as the causative factor. The remaining three patients had stent-induced complications. In cases of mechanical obstruction, recanalization occurred due to the use of intra-arterial thrombolytic agents in one of two patients. Nevertheless, a poor prognosis was seen. In the cases of stent-induced complications, in one of three patients in whom a thrombus developed following stent insertion, a middle cerebral artery territory infarct developed with a poor prognosis despite the use of wiring and an intra-arterial thrombolytic agent. In the cases of distal embolic stroke, all three patients achieved good results following the use of antiplatelet agents. Conclusion : Treatment for thromboemboic complications due to mechanical obstruction and stent-induced complications include antiplatelet and intra-arterial thrombolytic agents; however, this cannot guarantee a sufficient extent of effectiveness. Therefore, active treatments, such as balloon angioplasty, stent insertion, and clot extraction, are helpful.

• Journal of Veterinary Clinics
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• v.33 no.3
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• pp.155-159
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• 2016

Four dogs were brought to the Veterinary Medicine Teaching Hospital of Seoul National University (VMTH SNU) with a history of hind limb ataxia, three with pain, one without pain. Three of the four showed weak to absent femoral pulses and cold extremities. Thromboembolism was identified by ultrasonography in the external and/or internal iliac arteries. A thrombolytic agent, recombinant tissue plasminogen activator (rt-PA), was administered (0.5-1 mg/kg, every 60-120 min, 3-5 doses). Two dogs (Cases 2 and 3), which were instantly provided rt-PA treatment, survived 6 and 17 months, respectively, although hematemesis and hematochezia were observed during treatment. In the other two dogs (Cases 1 and 4), rt-PA was administered 4 and 28 days after the appearance of pelvic limb symptoms, which may have limited the benefits of the treatment. When rt-PA treatment is instituted instantly and the side effects are monitored thoroughly during treatment, a good prognosis might be expected in canine aortic thromboembolism. For this reason, we suggest that rt-PA treatment should be initiated immediately if thromboembolism is identified.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1449-1459
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• 2015

A novel proteolytic enzyme with fibrinolytic activity, FSP3, was purified from the recently isolated Streptomyces sp. P3, which is a novel bacterial strain isolated from soil. FSP3 was purified to electrophoretic homogeneity by ammonium sulfate precipitation, anion exchange, and gel filtration. FSP3 is considered to be a single peptide chain with a molecular mass of 44 kDa. The maximum activity of the enzyme was observed at 50℃ and pH 6.5, and the enzyme was stable between pH 6 and 8 and below 40℃. In a fibrin plate assay, FSP3 showed more potent fibrinolytic activity than urokinase, which is a clinical thrombolytic agent acting as a plasminogen activitor. The activity was strongly inhibited by the serine protease inhibitor PMSF, indicating that it is a serine protease. Additionally, metal ions showed different effects on the activity. It was significantly suppressed by Mg²⁺ and Ca²⁺ and completely inhibited by Cu²⁺, but slightly enhanced by Fe²⁺. According to LC-MS/MS results, its partial amino acid sequences are significantly dissimilar from those of previously reported fibrinolytic enzymes. The sequence of a DNA fragment encoding FSP3 contained an open reading frame of 1287 base pairs encoding 428 amino acids. FSP3 is a bifunctional enzyme in nature. It hydrolyzes the fibrin directly and activates plasminogen, which may reduce the occurrence of side effects. These results suggest that FSP3 is a novel serine protease with potential applications in thrombolytic therapy.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2607-2612
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• 2010

Human tissue-type plasminogen activator (tPA) is a valuable thrombolytic agent used to successfully treat acute myocardial infarction, thromboembolic stroke, peripheral arterial occlusion, and venous thromboembolism. Recombinant tPA is accumulated as an inactive form in inclusion bodies of E. coli and is refolded in vitro, which is accompanied by extensive aggregation. In the present study, a tPA protease domain was expressed in an active soluble form in the cytosol of E. coli Rosetta-gami cells, which allowed disulfide bond formation and supplied the tRNA molecules required for six rarely used codons in E. coli. This strategy increased the amount of soluble protease domain protein and avoided the cumbersome refolding process. The purified protease domain not only degraded tPA substrate peptides but also formed a covalently bound complex with plasminogen activator inhibitor-1, as does full-length tPA. Soluble expression and purification of tPA domains may aid in functional analyses of this multi-domain protein, which has been implicated in many physiological and pathological processes.

• Biomolecules & Therapeutics
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• v.3 no.2
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• pp.159-164
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• 1995

Fibrinolytic and fibrinogenolytic activities of the venoms from the Korean snakes, Agkistrodon caliginosus, nosus, Agkistrodon saxatilis and Agkistrodon blomhoffi brevicaudus were compared by fibrin-plate method and polyacrylamide gel electrophoresis, respectively. The venom from A. blomhoffi brevicaudus showed the highest degree of fibrin(ogen)olytic activity, and a protease with the fibrin(open)olytic activity was purified by p-amino-benzamidine affinity chromatography and DEAE ion-exchange chromatography. The purified enzyme had a molecular weight of 50,800 and a capability to degrade the B$\beta$-chain of fibrinogen preferentially to the $A\alpha$-chain, but not the ${\gamma}$-chain. Fibrinolytic activity of the purified enzyme was approximately 3.8 plasmin unit/mg protein.

• Journal of Microbiology and Biotechnology
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• v.29 no.9
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• pp.1361-1368
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• 2019

Codium fragile is an edible seaweed in Asian countries that has been used as a thrombolytic, anticoagulant, antioxidant, anti-inflammatory, and immune-stimulatory agent. Ginseng has also been known to maintain immune homeostasis and to regulate the immune system via enhancing resistance to diseases and microorganisms. In this study, anionic macromolecules extracted from C. fragile (CFAM) were orally administered with red ginseng extract (100 mg/kg body weight) to cyclophosphamide-induced immunosuppressed male BALB/c mice to investigate the immune-enhancing cooperative effect of Codium fragile and red ginseng. Our results showed that supplementing CFAM with red ginseng extract significantly increased spleen index, T- and B-cell proliferation, NK cell activity, and splenic lymphocyte immune-associated gene expression compared to those with red ginseng alone, even though a high concentration of CFAM with red ginseng decreased immune biomarkers. These results suggest that CFAM can be used as a co-stimulant to enhance health and immunity in immunosuppressed conditions.