• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.497-502
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• 2018

The coronary artery disease (CAD) is rapidly increasing such as angina pectoris and atherosclerosis. The CAD is induce by cholesterol and calcium like plaque absortion to artery wall. The percutaneouss coronary intervention is non-invasive treatment that narrowed-artery is expand by using balloon catheter and bare metallic stent. The metallic stents have been effective in reducing the dead by coronary artery disease, but the permanent presence of the metallic stent has been associated with persistent inflammation, and incidence of late thrombosis. Therefore, development bioresorbable vascular scaffold (BRS) is rapidly increasing for treatment of long-term complications and arterial restenosis by permanentmetal prosthesis such as stent. The review discusses the BRS trend for successfully development.

• Archives of Craniofacial Surgery
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• v.21 no.5
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• pp.269-275
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• 2020

Background: The advance in microsurgical technique has facilitated a proper approach for reconstruction of extensive head and neck defects. For the success of free tissue reconstruction, selection of the recipient vessel is one of the most important factors. However, the vascular anatomy of this region is very complex, and a clear guideline about this subject is still lacking. In this study, we present our 30 years of experiences of free tissue reconstruction for head and neck defects. Methods: In this retrospective study, we analyzed a total of 138 flaps in 127 patients who underwent head and neck reconstruction using free tissue transfer following tumor resection between October 1986 to August 2019. Patients who underwent facial palsy reconstruction were excluded. Medical records including patient's demographics, detailed operation notes, follow-up records, and photographs were collected and analyzed. Results: Among a total of 127 patients, 10 patients underwent a secondary operation due to cancer recurrence. The most commonly used type of flap was radial forearm flap (n=107), followed by the anterolateral thigh flap (n=18) and fibula flap (n=10). With regard to recipient vessels, superior thyroid artery was most commonly used in arterial anastomosis (58.7%), and internal jugular vein (51.3%) was the first choice for venous anastomosis. The flap survival rate was 100%. Four cases of venous thrombosis were resolved with thrombectomy and re-anastomosis. Conclusion: Superior thyroid artery and internal jugular vein were reliable choices as recipient vessels. Proper recipient vessel selection could improve the result of head and neck reconstruction.

• Journal of Korean Neurosurgical Society
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• v.47 no.4
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• pp.258-264
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• 2010

Objective : The objectives of this study were to analyze the outcome and hemorrhagic risk of intravenous (IV) argatroban in patients with acute ischemic stroke presenting beyond six hours of ischemic symptom onset. Methods : Eighty patients with acute ischemic stroke who were admitted to the hospital beyond six hours from ischemic symptom onset were retrospectively analyzed. We could not perform IV thrombolysis or intra-arterial thrombolysis because of limited time window. So, IV argatroban was performed to prevent recurrent thrombosis and progression of infarcted area. The outcome was assessed by the National Institute of Health Stroke Scale (NIHSS) score and related hemorrhagic risk was analyzed. Also, each outcome was analyzed according to the initial stroke severity, subtype, and location. Results : The median NIHSS was 8.0 at admission, 4.1 upon discharge, and 3.3 after three months. A good outcome was achieved in 81% of patients upon discharge and 88% after three months. Symptomatic hemorrhage occurred in only two patients (3%). IV argatroban was effective regardless of initial stroke severity, subtype, and location. Conclusion : IV argatroban may be an effective and safe treatment modality for acute ischemic stroke presenting beyond six hours of ischemic symptom onset.

• KSBB Journal
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• v.27 no.6
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• pp.375-380
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• 2012

We previously reported that Ultra nattokinase$^{(R)}$ showed high fibrinolytic activity and revealed antithrombotic effect in rat blood plasma based on its ability to suppress collagen-induced platelet aggregation. This research was carried out to verify the clot lysing activity and blood flow enhancing effects of Ultra nattokinase$^{(R)}$ via monitoring and comparing the antithrombotic effects in rat artery between oral administration of Ultra nattokinase$^{(R)}$ and maltodextrin. SD rats were fed with 1.11 mg/kg of Ultra nattokinase$^{(R)}$ for 4 weeks. The effect on arterial thrombosis was then evaluated using an antithrombotic model after induction by $FeCl_3$. Detected fibrinolytic activity was proportional to the content of Ultra nattokinase$^{(R)}$ and statistical extents of the antithrombotic activity was enhanced strongly twice rather than control group. The PT and the aPTT, however, showed only a small difference between two groups. The results suggest that Ultra nattokinase$^{(R)}$ can effectively treat thromboembolism and enhance blood flow, and that Ultra nattokinase$^{(R)}$ can also prevent venous occlusion by aiding clot lysis.

• Journal of Biomedical Engineering Research
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• v.23 no.4
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• pp.281-286
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• 2002

In this study, blood flow in a carotid artery supplying blood to the human's brain has been numerically simulated to find out how the blood flow affects the genesis and the growth of atherosclerosis and arterial thrombosis. Velocity Profiles and hemodynamic parameters have been investigated for the carotid arteries with three different stenoses under physiological flow condition. Blood has been treated as Newtonian and non-Newtonian fluid. To model the shear thinning properties of blood for non-Newtonian fluid, the Carreau-Yasuda model has been employed. The result shows that the wall shear stress(WSS) increases with the development of stenosis and that the wall shear stress in Newtonian fluid is highly evaluated compared with that in non-Newtonian Fluid. Oscillatory shear index has been employed to identify the time-averaged reattachment point and this point is located farther from the stenosis for Newtonian fluid than for non-Newtonian fluid The wall shear stress gradient(WSSG) along the wall has been estimated to be very high around the stenosis region when stenosis is developed much and the WSSG peak value of Newtonian fluid is higher than that of non-Newtonian fluid.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.2
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• pp.265-269
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• 1999

Thrombocytopenic patients without detectable bound antiplatelet antibody should be diagnosed with idiopathic thrombocytopenic purpura (ITP) if no other cause of their decreased platelet count could be found. More recently the term "autoimmune thrombocytopenic purpura (ATP) has supplanted ITP since the disease is related to the production of autoantibodies against one's own platelets. This entity should not be confused with isoimmune thrombocytopenic purpura (also called alloimmune thrombocytopenic purpura). In this cases maternal antiplatelet antibodies directed against the PLA 1 antigen on the fetal platelets causes severe fetal and neonatal thrombocytopenia in a situation analogous to Rheusus disease. Antibodies to the negatively charged phospholipids, lupus anticoagulant, and anticardiolipin have been linked to adverse pregnancy events. Pregnant women possessing these antibodies have an increased risk of spontaneous abortion, stillbirths, intrauterine fetal growth retardation, preterm birth, and arterial and venous thrombosis. Antiphospholipid antibodies decrease or may even disappear between pregnancies only to recur with increased activity in a subsequent pregnancy and lead to loss. We have experienced a case of antiphospholipid syndrome associated with autoimmune thrombocytopenic purpura in patient with recurrent spontaneous abortion. So we report this case with a brief review of literatures.

• Journal of Korean Neurosurgical Society
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• v.64 no.6
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• pp.853-863
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• 2021

Objective : Biodegradable poly-L-lactic acid (PLLA) with a highly biocompatible surface via tantalum (Ta) ion implantation can be an innovative solution for the problems associated with current biodegradable stents. The purpose of this study is to develop a Taimplanted PLLA stent for clinical use and to investigate its biological performance capabilities. Methods : A series of in vitro and in vivo tests were used to assess the biological performance of bare and Ta-implanted PLLA stents. The re-endothelialization ability and thrombogenicity were examined through in vitro endothelial cell and platelet adhesion tests. An in vivo swine model was used to evaluate the effects of Ta ion implantation on subacute restenosis and thrombosis. Angiographic and histologic evaluations were conducted at one, two and three months post-treatment. Results : The Ta-implanted PLLA stent was successfully fabricated, exhibiting a smooth surface morphology and modified layer integration. After Ta ion implantation, the surface properties were more favorable for rapid endothelialization and for less platelet attachment compared to the bare PLLA stent. In an in vivo animal test, follow-up angiography showed no evidence of in-stent stenosis in either group. In a microscopic histologic examination, luminal thrombus formation was significantly suppressed in the Ta-implanted PLLA stent group according to the 2-month follow-up assessment (21.2% vs. 63.9%, p=0.005). Cells positive for CD 68, a marker for the monocyte lineage, were less frequently identified around the Ta-implanted PLLA stent in the 1-month follow-up assessments. Conclusion : The use of a Ta-implanted PLLA stent appears to promote re-endothelialization and anti-thrombogenicity.

• Archives of Plastic Surgery
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• v.46 no.3
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• pp.214-220
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• 2019

Background Microvascular anastomosis patency is adversely affected by local and systemic factors. Impaired intimal recovery and endothelial mechanisms promoting thrombus formation at the anastomotic site are common etiological factors of reduced anastomosis patency. Epigallocatechin gallate (EGCG) is a catechin derivative belonging to the flavonoid subgroup and is present in green tea (Camellia sinensis). This study investigated the effects of EGCG on the structure of vessel tips used in microvascular anastomoses and evaluated its effects on thrombus formation at an anastomotic site. Methods Thirty-six adult male Wistar albino rats were used in the study. The right femoral artery was cut and reanastomosed. The rats were divided into two groups (18 per group) and were systemically administered either EGCG or saline. Each group were then subdivided into three groups, each with six rats. Axial histological sections were taken from segments 1 cm proximal and 1 cm distal to the microvascular anastomosis site on days 5, 10, and 14. Results Thrombus formation was significantly different between the EGCG and control groups on day 5 (P=0.015) but not on days 10 or 14. The mean luminal diameter was significantly greater in the EGCG group on days 5 (P=0.002), 10 (P=0.026), and 14 (P=0.002). Intimal thickening was significantly higher on days 5 (P=0.041) and 10 (P=0.02). Conclusions EGCG showed vasodilatory effects and led to reduced early thrombus formation after microvascular repair. Similar studies on venous anastomoses and random or axial pedunculated skin flaps would also contribute valuable findings relevant to this topic.

• Journal of the Korean Orthopaedic Association
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• v.56 no.5
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• pp.450-454
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• 2021

A 75-year-old male patient without any significant medical and habitual risk factors for acute atherosclerosis obliterans except for hypertension was diagnosed with coronavirus disease 2019 with dyspnea, coughing, and mild fever. After a week of hospitalization, he complained of right foot pain and numbness. The symptoms were aggravated during the next week, resulting in a complete toe color change and loss of dorsalis artery pulse. Enhanced 3-dimensional computed tomography angiography revealed thrombus formation in the right common iliac artery and a loss of blood flow below the popliteal artery on both sides. The patient underwent percutaneous balloon angioplasty with stent insertion followed by medical therapy for anticoagulation. The clinical symptoms immediately were improved after the intervention, but the great toe necrosis was not recovered. Finally, amputation of the great toe was performed.

• Clinical Pain
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• v.19 no.2
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• pp.116-119
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• 2020

Cervical transforaminal epidural steroid injection (TFESI) is commonly performed to provide relief of pain caused by radiculopathy. Intra-arterial injection of particulate steroid or direct needle injury can lead to spinal artery embolism or thrombosis. Also there is a possibility of vascular spasm. To our knowledge, this is the first reported case of spinal cord infarction that occurred after TFESI with non-particulate steroid in Korea. A 47-year-old female patient underwent C7 TFESI at local pain clinic. Injected materials were dexamethasone and mepivacaine. Right after the intervention, she felt muscle weakness and decreased sensation. On physical examination, she had decreased sensation from C4 to T2 dermatome in light touch and pin-prick test. Proprioception and vibration were intact. The motor grades of upper extremities were grade 1. Cervical and thoracic spine MRI was checked. Diffusion-weighted image and apparent diffusion coefficient image showed long extension of spinal cord infarction from C2 to T1 level.