• 대한화학회지
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• 제36권6호
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• pp.947-954
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• 1992

Poly (γ-benzyl L-glutamate) (PBLG)와 말단에 아미노기를 갖는 Polyethylene glycol (PEG)의 치환반응을 행하여 PEG-grafted PBLG (PEG-g-PBLG)를 합성하였다. 또한 PEG-g-PBLG 필름표면에 ethanolamine(EA)을 치환반응하여 표면에 히드록시그룹을 갖는 PEG-g-PBLG-EA 필름을 얻었다. 폴리펩티드중합체와 혈액성분과의 상호작용에 관한 실험결과, PEG-g-PBLG 상에서의 혈소판의 점착율 및 형태변화는 PEG-g-PBLG-EA보다 적게 나타났고, PEG-g-PBLG상에서의 혈장 단백질의 응고시간은 PEG-g-PBLG-EA 또는 PBLG의 응고시간보다 길게 나타났다. 이들 결과는 혈액응고시간 및 혈액응고량을 조사한 실험결과와 일치하였다. 따라서 폴리펩티드상의 히드록시그룹은 혈액성분과의 상호작용을 강하게 하여 혈액적합성이 저하하는 반면, PEG-g-PBLG는 비교적 좋은 혈액적합성을 나타냄을 알 수 있었다.

• 대한의용생체공학회:의공학회지
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• 제23권5호
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• pp.375-383
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• 2002

코일을 이용한 동맥류 색전술은 동맥류 내부에 코일을 삽입하여 혈류 유동의 정체를 유도하여 혈전을 형성시키므로 동맥류를 폐색하는 방법이다. 코일을 이용하여 동맥류를 부분 폐색할 경우 동맥류의 폐색 위치에 따라 동맥류 내부의 유동 특성이 변하며, 이는 동맥류 내부의 현전 형성에 영향을 미칠 수 있다. 본 연구에서는 내경 동맥에서 발생한 측방 동맥류에 코일로 인한 부분 폐색이 발생할 경우, 부분 폐색 위치 및 내경 동맥의 곡률 반경의 변화에 따른 동맥류 내부 혈류 유동의 변화를 생체외 모델 실험을 이용하여 측정하여, 효율적인 동맥류 폐색 위치를 제시하고자한다. 내경동맥에서 발생한 측방 동맥류 내부에 코일을 동맥류 천정 근위부, 천정 원위부, 목 근위부 및 목 원위부에 각각 삽입하여 폐색 위치가 다른 모델을 제작하여, 입자영상속도계를 이용하여 속도장을 측정하였다. 동맥류 주머니의 원위부 폐색은 근위부 폐색에 비해 동맥류 내부고의 유입되는 유동이 적었으므로 동맥류 원위부 폐색이 혈전의 형성 및 동맥류 색전에 효율적임을 나타냈다. 동맥류 목 원위부 폐색은 천정 원위부 폐색에 비해 동맥류 내부로 혈류 유입을 효율적으로 차단하였으므로, 목 원위부 폐색이 동맥류 색전에 가장 효율적인 위치임을 알 수 있었다.

• Journal of Korean Neurosurgical Society
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• 제64권6호
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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.

• Journal of Ginseng Research
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• 제43권2호
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• pp.236-241
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• 2019

Background: Thromboxane A2 ($TXA_2$) induces platelet aggregation and promotes thrombus formation. Although ginsenoside Ro (G-Ro) from Panax ginseng is known to exhibit a $Ca^{2+}-antagonistic$ antiplatelet effect, whether it inhibits $Ca^{2+}-dependent$ cytosolic phospholipase $A_2$ ($cPLA_{2{\alpha}}$) activity to prevent the release of arachidonic acid (AA), a $TXA_2$ precursor, is unknown. In this study, we attempted to identify the mechanism underlying G-Ro-mediated $TXA_2$ inhibition. Methods: We investigated whether G-Ro attenuates $TXA_2$ production and its associated molecules, such as cyclooxygenase-1 (COX-1), $TXA_2$ synthase (TXAS), $cPLA_{2{\alpha}}$, mitogen-activated protein kinases, and AA. To assay COX-1 and TXAS, we used microsomal fraction of platelets. Results: G-Ro reduced $TXA_2$ production by inhibiting AA release. It acted by decreasing the phosphorylation of $cPLA_{2{\alpha}}$, p38-mitogen-activated protein kinase, and c-Jun N-terminal kinase1, rather than by inhibiting COX-1 and TXAS in thrombin-activated human platelets. Conclusion: G-Ro inhibits AA release to attenuate $TXA_2$ production, which may counteract $TXA_2-associated$ thrombosis.

• Journal of Applied Biological Chemistry
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• 제62권1호
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• pp.93-100
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• 2019

The root of Panax ginseng is used in ethnomedicine throughout eastern Asia and various recent studies have proved that Panax ginseng has inhibitory effects on cardiovascular disease. Each factor causing cardiovascular disease is known to have a very complex process which is achieved by a diverse number of mechanisms. Among these factors, platelets are the most important because they directly participate in thrombogenesis. Therefore, inhibiting the activity of platelets is an essential element for prevention of cardiovascular diseases. Our previous study showed the antiplatelet effects of Korean red ginseng extract and two of its components, ginsenoside Rg3 and ginsenoside Ro. However, the inhibitory mechanism of other ginsenosides remains unclear. Therefore, we investigated the inhibitory mechanism of ginsenoside F4 (G-F4) from Korean red ginseng on the regulation of signaling molecules involved in human platelet aggregation. With the use of G-F4, collagen-induced human platelet aggregation was inhibited in a dose-dependent manner, and it suppressed collagen-induced elevation of $[Ca^{2+}]_i$ mobilization through elevated phosphorylation of inositol 1, 4, 5-triphosphate receptor I ($Ser^{1756}$). In addition, G-F4 inhibited fibrinogen binding to ${\alpha}IIb/{\beta}_3$ during collagen-induced human platelet aggregation. Thus, in the present study, G-F4 showed an inhibitory effect on human platelet activation, suggesting its potential use as a new natural medicine for preventing platelet-mediated cardiovascular diseases.

• Journal of Ginseng Research
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• 제45권4호
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• pp.490-497
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• 2021

Background and objective: Synthetic ginsenoside compounds G-Rp (1,3, and 4) and natural ginsenosides in Panax ginseng 20(S)-Rg3, Rg6, F4 and Ro have inhibitory actions on human platelets. However, the inhibitory mechanism of ginsenoside Rk1 (G-Rk1) is still unclear thus, we initiated investigation of the anti-platelet mechanism by G-Rk1 from Panax ginseng. Methodology: Our study focused to investigate the action of G-Rk1 on agonist-stimulated human platelet aggregation, inhibition of platelet signaling molecules such as fibrinogen binding with integrin α_IIbβ₃ using flow cytometry, intracellular calcium mobilization, fibronectin adhesion, dense granule secretion, and thromboxane B2 secretion. Thrombin-induced clot retraction was also observed in human platelets. Key Results: Collagen, thrombin, and U46619-stimulated human platelet aggregation were dose-dependently inhibited by G-Rk1, while it demonstrated a more effective suppression on collagen-stimulated platelet aggregation using human platelets. Moreover, G-Rk1 suppressed collagen-induced elevation of Ca²⁺ release from endoplasmic reticulum, granule release, and α_IIbβ₃ activity without any cytotoxicity. Conclusions and implications: These results indicate that G-Rk1 possess strong anti-platelet effect, proposing a new drug candidate for treatment and prevention of platelet-mediated thrombosis in cardiovascular disease.

• 대한정형외과학회지
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• 제56권5호
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• pp.450-454
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• 2021

고혈압 이외에 급성 폐쇄동맥경화증의 내과적 위험요소가 없던 75세 남자 환자가 경한 발열을 동반한 기침, 호흡 곤란으로 내원하여 코로나바이러스감염증-19 진단을 받았다. 격리입원 치료를 시작한 지 1주일째에, 우측 족부의 동통 및 저린감을 호소하기 시작하였으며, 그 다음 1주일 동안 서서히 한랭감, 전족지의 색깔 변화와 족배동맥의 소실이 나타나게 되었다. 하지 혈관조영 3차원 컴퓨터 단층촬영 검사에서 좌, 우측 모두에서 슬와동맥 이하로 전, 후경골 동맥 및 비골동맥의 혈류가 관찰되지 않았으며, 우측 총장 골동맥 내부에 혈전이 생성되어 있는 모습을 확인할 수 있었다. 우측 하지에 대하여 경피적 풍선 혈관 성형술 및 스텐트 삽입술, 항응고제 투여를 시행하였으며, 시술 직후부터 우측 족배동맥의 맥박이 온전히 촉지되고, 호소하던 한랭감이 개선되었음을 확인하였다. 혈류가 개선되었음에도 불구하고 우측 족무지의 괴사는 회복되지 않아 결국 족무지 절단술을 시행하였다.

• Archives of Pharmacal Research
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• 제26권3호
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• pp.224-231
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• 2003

The anti-thrombotic effects of LB30057, a direct thrombin inhibitor, were evaluated with in vivo rat and dog thrombosis models. In rats, 1 mg/kg of LB30057 inhibited half of the clot formations in the inferior vena cava at 5 minutes after intravenous application. When measured at 2 hours after oral application, 100 mg/kg prevented approximately half of the clot formations in the inferior vena cava and 50 mg/kg prolonged the mean occlusion time from $15.6{\pm}1.3$ minutes to $47.2{\pm}8.3$ minutes in the carotid artery. In dogs, the formation of thrombus in the jugular vein was reduced to half at a dose range of 20-30 mg/kg at 6 hours after oral application. In addition, the LB30057 dosage required to reduce venous clot formation by approximately 80-90% in dogs was only about 10% of that required for the same reduction in rats. This is probably due to the variation in its time-dependent blood concentration profiles in each species; for example, the plasma half-life of LB71350 in dogs was longer than that in rats ($153.0{\pm}3.0$ vs. $129.7{\pm}12.7$ min at 30 mg/kg, i.v., respectively). AUG, $T_{max},{\;}G_{max}$, and BA in dogs were 59, 8.9, 9.17, and 13.3 times higher than those in rats at oral 30 mg/kg, respectively. Taken together, these results suggest that LB30057 administered orally is effective in the prevention of arterial and venous thrombosis in rats and dogs. It therefore represents a good lead compound for investigations to discover a new, orally available, therapeutic agent for treating thrombotic diseases.

• 한국축산식품학회지
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• 제24권2호
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• pp.189-197
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• 2004

본 실험은 삼겹살 기름의 섭취가 흰쥐의 혈액 지질함량 변화에 미치는 영향을 알아보기 위해서 수행하였다. 흰쥐식이에 옥수수기름을 5％ 첨가하여 급여한 처리구(대조구), 상업용 돼지기름으로서 정제된 라드를 5％ 혼합 급여한 처리구(T1), 삼겹살 기름을 5％ 첨가 급여한 처리구(T2), 삼겹살 기름을 10％ 첨가 급여한 처리구(T3) 및 옥수수기름 5％ 첨가 급여구(대조구)와 삼겹살 기름 10％ 첨가 급여구(T3)를 각각 3일씩 교체 급여한 처리구(T4)등 5개 처리구로 나누어서 각각 6반복씩 완전임의 배치한 후 30일간 사육한 결과는 다음과 같다. 식이섭취량 및 식이효율은 처리구간에 일정 한 차이가 없었으며, 증체량에 있어서는 삼겹살 기름을 첨가 급여하였을 때 유의적으로 높아지는 경향을 보였다.(p＜0.05). 혈액 중성지방은 T3가 나머지 네 급여구에 비해서 높았으며 대조구와 비교할 때 삼겹살 기름을 첨가 급여할수록 모든 처리구가 유의적으로 증가하였다(p＜0.05). 혈액 총 콜레스테롤은 T3가 가장 높았고 T1, T2, T4순으로 높게 나타났으며 대조구와 삼겹살기름 첨가구 사이에는 통계적 유의성이 있었다. (p＜0.05). 혈액 HDLㆍC 함량은 T2와 T3가 가장 낮은 경향을 보여줬으나 T1, T2, T3, T4 사이에 유의적인 차이는 나타나지 않았으며 대조구와 비교할 때 삼겹살 기름을 첨가 급여할수록 모든 처리구가 유의적으로 낮아지는 경향을 보여줬다(p＜0.05). 혈액 LDLㆍC와 Al는 T3가 가장 높았고, T1, T2, T4 순으로 높게 나타났으며 대조구와 삼겹살 기름 첨가구 사이에 통계적으로 유의한 차이가 있었다(p＜0.05). 출혈시간은 삼겹살 기름을 첨가 급여하였을 때 유의적으로 단축되는 경향을 나타냈으며 T3가 가장 짧았고 처리구간 유의적인 차이가 있었다(p＜0.05). 전혈 응고시간은 T3가 가장 단축되었고 삼겹살 기름을 첨가급여 할수록 단축되는 경향이 있었으며 처리구간 통계적인 유의성이 있었다.(p＜0.05). 본 연구의 결과는 돼지고기 삼겹살의 잦은 섭취 또는 과잉섭취가 혈액 내 중성지방과 유해 콜레스테롤 함량을 높여줌으로서 혈전 형성을 가속화 할 수 있음을 보여주며 이는 삼겹살 기름에 함유되어 있는 포화지방산과 콜레스테롤 함량이 높은 데 기인함을 시사해 준다.

• Journal of Korean Neurosurgical Society
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• 제30권6호
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• pp.805-812
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• 2001

Objectives : The goal of the surgical management of large and giant aneurysm is complete extirpation of the aneurysms with preservation or reconstruction of the parent artery. To improve the surgical management results of those aneurysms in the future, we review our experience and discuss technical maneuvers and strategies used to avoid potential complications of those aneurysm surgery. Material and Methods : During the past 12 years, thirty six cases of large and giant aneurysms(diameter>19mm) were managed by surgery. The clinical characteristics, treatment methods, surgical complications and outcome of those cases were analyzed and, based on the review of the literatures, the preventive methods of surgical complication related to the clipping of those aneurysms were discussed. Results : The locations of those aneurysms were anterior circulation in 34 cases and posterior circulation in 2 cases. The most frequent site of aneurysmal location was a paraclinoidal region of the anterior circulation. The aneurysms were managed surgically by direct clipping of aneurysmal neck in 31 cases, aneurysmal trapping followed by extracranial-intracranial bypass in 2 cases, proximal clipping of parent artery, aneurysmorrhaphy, and excision of aneurysm followed by end to end anastomosis of parent artery in each one case. Surgical complications occurred in 13 cases. A parent vessel occlusion by thrombus formation and parent vessel stenosis after clipping of aneurysm were the main complications. We obtained good outcome in 27, fair 5, poor 1 and dead in 3 case(s). Conclusion : We conclude that selection of suitable management method for each case, high quality of surgical technique and prevention of complication during operation are important key points for the successful treatment of large and giant aneurysm. The heparinization prior to application of temporary clip on parent vessels, aneurysmal decompression during dissection and clipping of aneurysm, complete closing of the aneurysmal neck and avoiding the narrowing of parent vessel after clipping of aneurysm were the main technical maneuvers used to avoid complications of those aneurysm surgery.