• Journal of Korean Neurosurgical Society
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• 제66권3호
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• pp.263-273
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• 2023

While the survival rate of preterm infants has increased dramatically over the last few decades, intraventricular hemorrhage and subsequent hydrocephalus remain major unsolved problems in neonatal intensive care. Once intraventricular hemorrhage occurs, severe neurological sequelae are inevitable. Treatment of this complicated pathology and achievement of favorable neurofunctional outcomes in fragile infants are crucial challenges for pediatric neurosurgeons. Fibrinolytic therapy, which chemically dissolves hematoma, is a promising and useful treatment method. In this paper, the historical background of fibrinolytic therapy for post-intraventricular hemorrhagic hydrocephalus in preterm infants is reviewed and a recent method of fibrinolytic therapy using urokinase is introduced.

• The Journal of Korean Physical Therapy
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• 제25권4호
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• pp.224-231
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• 2013

Purpose: The purpose of this case study was to investigate three poor fibrinolytic responders with chronic ischemic stroke to acute exercise intensity and time. Methods: Three ischemic stroke patients (male) from the stroke center located at Busan metropolitan area in Republic of Korea volunteered at this study. They performed two single session exercises that were a VO2peak test and a single bout treadmill walking (70-75%HRpeak, 30 min, 50min). Fasting blood samples for determination of tissue Plasminogen Activator (tPA) and Plasminogen Activator Inhibitor-1 (PAI-1) were obtained before, immediately after, 30min after acute exercise. SPSS 12.0 was used for analyzing of data and computing mean and standard deviation, and change rate was conducted between times. Results: In fibrinolytic activity according to the intensity and time of acute exercise, tPA change increased steadily during the recovery stage after the VO2peak in the cases, but PAI-1 activity showed different patterns among the cases. In a single bout treadmill walking (70-75%HRpeak, 30 min, 50min), tPA change increased between 30min and 50min. Conclusion: In conclusion, these results suggest that the exercise prescription for poor fibrinolytic responder with three male chronic ischemic stroke patients without motor disability recommend at 70-75%HRpeak, over 30min.

• Tuberculosis and Respiratory Diseases
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• 제76권3호
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• pp.127-130
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• 2014

The risk of dying from a pulmonary embolism (PE) is estimated to be about 30% if inotropic support is required and no cardiopulmonary arrest occurs. Fibrinolysis in massive PE is regarded as a life-saving intervention, unless there is a high risk of bleeding following the use of the fibrinolytic therapy. Rivaroxaban is an oral factor Xa inhibitor, however its anticoagulation effects before or after administration of fibrinolytics in massive PE are still unknown. Two patents were admitted: 61-year-old woman with repeated syncope, and a 73-year-old woman was admitted with dyspnea and poor oral intake. Systemic arterial hypotension with radiologic confirmation led to a diagnosis of massive PE in both patients. Rivaroxaban was administered before in one, and after firbrinolytic therapy in the other. One showed similar efficacy of rivaroxaban with currently used anticoagulants after successful fibrinolysis, and the other one without antecedent administration of the fibrinolytic agent showed unfavorable efficacy of rivaroxaban.

• Journal of Biomedical Engineering Research
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• 제15권1호
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• pp.9-18
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• 1994

• Journal of Microbiology and Biotechnology
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• 제25권9호
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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.

• Journal of Microbiology and Biotechnology
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• 제31권2호
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• pp.327-337
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• 2021

Fibrinolytic enzymes with a direct mechanism of action and safer properties are currently requested for thrombolytic therapy. This paper reports on a new enzyme capable of degrading blood clots directly without impairing blood coagulation. This enzyme is also non-cytotoxic and constitutes an alternative to other thrombolytic enzymes known to cause undesired side effects. Twenty-four Bacillus isolates were screened for production of fibrinolytic enzymes using a fibrin agar plate. Based on produced activity, isolate S127e was selected and identified as B. subtilis using the 16S rDNA gene sequence. This strain is of biotechnological interest for producing high fibrinolytic yield and consequently has potential in the industrial field. The purified fibrinolytic enzyme has a molecular mass of 27.3 kDa, a predicted pI of 6.6, and a maximal affinity for Ala-Ala-Pro-Phe. This enzyme was almost completely inhibited by chymostatin with optimal activity at 48℃ and pH 7. Specific subtilisin features were found in the gene sequence, indicating that this enzyme belongs to the BPN group of the S8 subtilisin family and was assigned as AprE127. This subtilisin increased thromboplastin time by 3.7% (37.6 to 39 s) and prothrombin time by 3.2% (12.6 to 13 s), both within normal ranges. In a whole blood euglobulin assay, this enzyme did not impair coagulation but reduced lysis time significantly. Moreover, in an in vitro assay, AprE127 completely dissolved a thrombus of about 1 cc within 50 min and, in vivo, reduced a thrombus prompted in a rat tail by 11.4% in 24 h compared to non-treated animals.

• Journal of Microbiology and Biotechnology
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• 제24권2호
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• pp.245-253
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• 2014

A fibrinolytic enzyme was produced by an edible mushroom of Pleurotus ostreatus using submerged culture fermentation. The enzyme was purified from the culture supernatant by applying a combination of freeze-thaw treatment, ammonium sulfate precipitation, hydrophobic interaction, and gel filtration chromatographies. The enzyme was purified by a 147-fold, with a yield of 7.54%. The molecular masses of the enzyme an determined by gel filtration and SDS-PAGE were 13.6 and 18.2 kDa, respectively. The isoelectric point of the enzyme was 8.52. It hydrolyzed fibrinogen by cleaving the ${\alpha}$ and ${\beta}$ chains of fibrinogen followed by the ${\gamma}$ chains, and also activated plasminogen into plasmin. The enzyme was optimally active at $45^{\circ}C$ and pH 7.4. The enzyme activity was completely inhibited by EDTA, whereas protease inhibitors of TPCK, SBTI, PMSF, aprotinin and pepstatin showed no inhibition on its activity. The partial amino acid sequences of the enzyme as determined by Q-TOF2 were ATFVGCSATR, GGTLIHESSHFTR, and YTTWFGTFVTSR. These sequences showed a high degree of homology with those of metallo-endopeptidases from P. ostreatus and Armillaria mellea. The purified enzyme can also be applied as a natural agent for oral fibrinolytic therapy or prevention of thrombosis.

• Journal of Microbiology and Biotechnology
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• 제28권2호
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• pp.275-283
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• 2018

Ischemic stroke can result from blockage of blood vessels, forming fibrin clots in the body and causing irreparable brain damage. Remedial thrombolytic agents or anticoagulants have been studied; however, because the FDA-approved tissue plasminogen activator has low efficacy and side effects, it is necessary to develop safer and more effective treatment candidates. This study aimed at assessing the fibrinolytic and anticoagulation features of a novel serine protease extracted and purified from Diopatra sugokai, a polychaeta that inhabits tidal flats. The purified serine protease was obtained through ammonium sulfate precipitation, affinity chromatography, and ion-exchange chromatography. Its molecular size was identified via SDS-PAGE. To characterize its enzymatic activities, the protease activity at various pH and temperatures, and in the presence of various inhibitors, was measured via azocasein assay. Its fibrinolytic activity and anticoagulant effect were assessed by fibrin zymography, fibrin plate assay, and fibrinogenolytic activity assays. The novel 38 kDa serine protease had strong indirect thrombolytic activity rather than direct activity over broad pH (4-10) and temperature ($37^{\circ}C-70^{\circ}C$) ranges. In addition, the novel serine protease exhibited anticoagulant activity by degrading the ${\alpha}$-, ${\beta}$-, and ${\gamma}$-chains of fibrinogen. In addition, it did not produce cytotoxicity in endothelial cells. Therefore, this newly isolated serine protease is worthy of further investigation as a novel alkaline serine protease for thrombolytic therapy against brain ischemia.

• Journal of Mushroom
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• 제13권3호
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• pp.192-198
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• 2015

This study was performed in order to analyze the fibrinolytic, thrombin inhibitory, anti-oxidative, acetylcholinesterase inhibitory, and immuno-enhancing activities of the water extract and solvent fractions isolated from Grifola frondosa. Fibrinolytic activity was analyzed using the fibrin plate method, and thrombin inhibitory activity was assayed using the substrate H-D-Phe-piparg- pna. Anti-oxidative activity was estimated using the DPPH assay, and AChE inhibitory activity was measured using the spectrophotometric method. Immuno-enhancing activity was examined using the nitric oxide (NO) production in RAW 264.7 macrophage cells. Cell viability was determined using the MTS assay. Fibrinolytic activities were the highest in water extract (1.55 plasmin units/mL) followed by water fraction (0.85 plasmin units/mL). The thrombin inhibitory activities of the water and ethyl acetate fractions were determined to be 76.43% and 72.59%, respectively. The acetylcholinesterase inhibitory activities of chloroform and hexane fractions exhibited values of 95.14% and 94.74%, respectively. The butanol fraction showed the highest anti-oxidative activity at 94.47%. Anti-proliferating activity against Raw 264.7 cells showed no cytotoxicity. The production of NO in Raw 264.7 cells increased up to 2-fold by adding the water fraction compared to the untreated control. These results suggest that Grifola frondosa may serve as a useful functional food for the enhancement of immune function and the prevention and therapy of cardiovascular diseases.

• Tuberculosis and Respiratory Diseases
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• 제40권4호
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• pp.378-383
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• 1993

Background: In recent reports, it has been reported that increased coagulation and decreased fibrinolytic activity has been responsible for abnormal fibrin turnover in exudative pleural effusion. In the cases of empyema, the fibrinopurulent stage is characterized by the fibrin deposition resulting in formation of limiting membranes in the visceral and parietal pleura. Recently attention has been focused on intrapleural fibrinolytic therapy capable of removing intrapleural fibrin deposits by urokinase (UK) in the treatment of empyema. However, these clinical trials have provided the clinical evidences for resolution of pleural loculation after intrapleural urokinase injection (UK-injection), the profiles of fibrinolytic activity following the treatment were still not investigated. Therefore in order to demonstrate the fibrinolytic evidences behind the clinical efficacy of intracavitary UK-injection, we examined intrapleural plasminogen activator activity (PA-activity) and D-dimer (D-Di) concentrations before and after each repeated UK-injection into the pleura in subjects with loculated empyema cavity. Methods: In a group of 14 patients with multiple loculated empyema cavity, PA-activity and D-Di concentrations were measured before and after repeated UK-injection. One hundred thousand IU of UK was injected at each time and all sujects had at least two times of UK injection accoring to clinical decisions. Nine out of 14 sujects had three times of UK-injection. Results: The mean (${\pm}SE$) PA-activity prior to treatemnt was $10.5{\pm}7.0$ and it was increased to $91.9{\pm}27.0,\;432.3{\pm}177.1,\;170.0{\pm}85.3$ IU tPA/ml after first, second and third time of UK-injection respectively (p<0.01). D-Di concentrations were also increased from $4.16{\pm}1.06{\times}10^5$ to $9.62{\pm}1.54{\times}10^5,\;12.31{\pm}1.89{\times}10^5,\;8.54{\pm}1.56{\times}10^5$ ng/ml in the same order as above (p<0.05). Conclusion: The suppressed fibrinolytic activity in the empyema cavity get removed sinificantly after inrracavitary injection of urokinase by generation of additional intrapleural plasmin.