• Applied Microscopy
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• v.17 no.1
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• pp.65-75
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• 1987

The ultrastructure of the cutaneous chromatophores and the origin of pigment granules in the goldfish, Carassius auratus L., are studied with electron microscope. Leucophores contain amorphous pigment granules, leucosomes and melanosomes contain oval shaped electron dense melanin pigment granules. These pigment granules are synthesized from the Golgi complexes of each chromatophores and released into the cytoplasm. Among the dermal chromatophores, another kind of dermal cells, named rER rich cells, are also observed. And pinocytotic vesicles are being formed only the inner surface of the chromatophores adhering to the rER rich cells. From these observations, such hypothesis are being possible that pigment materials are synthesized and transfered from the rER rich cells to dermal chromatophores by the pinocytosis. And next remodelizing mechanisms are carried out by the Golgi complexes of each chromatophores.

• Korean Journal of Ichthyology
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• v.13 no.4
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• pp.254-260
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• 2001

In the goby Micropercops swinhonis, the follicular layer of full-grown oocytes consists of an outer layer (theca cell) and an inner layer (granulosa cell). As the oocyte grows, columnar cells of inner granulosa layer secrete mucin to their cytoplasm and then surround the oocyte. Such granulosa cells appear to be cuboidal cells in the early vitellogenesis, yolk vesicle stage, to be replaced by columnar cell secreting mucins (adhesive materials) in the middle vitellogenesis, yolk granule stage. The enveloping layer of the oocyte has a muco- follicle layer filled with mucins. The mucins are an amorphous and electron-dense substance. Interestingly, the oocyte enveloping layer becomes thickened towards the animal pole as vitelogenesis proceeds. A zona radiata of about $7.8{\sim}11.5\;{\mu}m$ thick is present below the muco-follicle layer. The zona radiata is composed of an one-layered electron-dense externa and a three to five-layered electron-less interna.

• Journal of the Korean Ceramic Society
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• v.55 no.6
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• pp.590-596
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• 2018

To improve the injection behavior of brushite cement, dense ${\beta}-Ca_3(PO_4)_2$ (${\beta}-TCP$) granules were added to the starting material. The spherical ${\beta}-TCP$ granules prepared by spray-drying and subsequent sintering at $1000{\sim}1200^{\circ}C$ accounted for fractions of from 0.5 to 0.7 of the total ${\beta}-TCP$. The injection behavior was evaluated by measuring the injected mass divided by the loaded mass of paste in the syringe pump. The injected amount was increased with the increase in the fraction and sintering temperature of ${\beta}-TCP$ granules, except at $1200^{\circ}C$. The increase in the fraction of ${\beta}-TCP$ and its sintering temperature resulted in a decrease in the plastic limit, which is the volume of water required to liquefy the compact. The rest water could be utilized in the cement with the reduced plastic limit for improved injectability. The amounts of rest water assigned for powdery phase were estimated, and correlated with the injectability of paste.

• YAKHAK HOEJI
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• v.38 no.1
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• pp.97-101
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• 1994

Platelets play a very important role in nomal hemostasis and their functions are more enhanced in various pathogenic states than in normal state. Especially it has been postulated that abnormal platelet and endothelium function might be major factors of microcirculatory disturbance in diabetes mellitus. Hydroxybrazilin, a phenolic constituent of Hematoxylon campechianum has been examined for its inhibitory effect on platelet aggregation. Its antiaggregatory effect might be mediated through the decrease of ATP release from dense granule and those of thromboxane $A_2$ production in normal and streptozotocin induced diabetic rats. The present study was undertaken to gain insight into the mechanism that hydroxybrazilin inhibited thromboxane $A_2$ production in platelets. Thus we measured the effect of hydroxybrazilin on phospholipase $A_2$, a rate limiting step of thromboxane $A_2$ production, in normal and streptozotocin induced diabetic rats. Hydroxybrazilin significantly inhibited the platelet phospholipase $A_2$ activity in normal and streptozotocin induced diabetic rats.

• BMB Reports
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• v.49 no.8
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• pp.449-454
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• 2016

Stress Granules (SGs) are microscopically visible, phase dense aggregates of translationally stalled messenger ribonucleoprotein (mRNP) complexes formed in response to distinct stress conditions. It is generally considered that SG formation is induced to protect cells from conditions of stress. The precise constituents of SGs and the mechanism through which SGs are dynamically regulated in response to stress are not completely understood. Hence, it is important to identify proteins which regulate SG assembly and disassembly. In the present study, we report Neuregulin-2 (NRG2) as a novel component of SGs; furthermore, depletion of NRG2 potently inhibits SG formation. We also demonstrate that NRG2 specifically localizes to SGs under various stress conditions. Knockdown of NRG2 has no effect on stress-induced polysome disassembly, suggesting that the component does not influence early step of SG formation. It was also observed that reduced expression of NRG2 led to marginal increase in cell survival under arsenite-induced stress.

• Applied Microscopy
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• v.27 no.1
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• pp.57-70
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• 1997

The distribution of glutamatergic synaptic structures in the dog basilar pons was investigated at the ultrastructural level using monoclonal antibodies against fixative-modified glutamate. Electron-dense reaction product was densely localized at the perinuclear region in the neurenal somata and often observed along the microtubules located within the dendritic processes. One or more unlabelled axon terminals made asymmetric synaptic contacts with glutamate-immunoreactive dendritic profiles. In audition, reaction product was observed either within axonal processes surrounded by myelin sheath or axon terminals. Immunoreactive axon terminals made asymmetric synaptic contact either with unlabelled or labelled dendritic profiles. These observations provided an anatomic evidence of how this excitatory neural element might perform its function in a multisynaptic pathway involving glutamatergic afferents to the basilar pons, glutamate-immunoreactive pontocerebellar projection neurons, and the glutamate-positive granule cells of the cerebellar cortex.

• International Journal of Advanced Culture Technology
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• v.6 no.4
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• pp.109-115
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• 2018

Garlic is a medicinal plant used throughout the world for its anti-inflammatory, antioxidant, and antiplatelet activities. Chitosan is a natural polysaccharide obtained from chitin, and derivatives of chitosan have been shown to inhibit platelet aggregation and adhesion. We hypothesized that fermented preparations of these products may possess stronger antiplatelet effects than the non-fermented forms owing to the increased bioavailability of the bioactive compounds produced during fermentation. Therefore, we compared these compounds via in vitro and ex vivo platelet aggregation assays by using standard light transmission aggregometry and ex vivo granule secretions from rat platelets. We found that fermented preparations exerted more potent and significant inhibition of platelet aggregation both in vitro and ex vivo. Likewise, ATP release from dense granules of platelets was also significantly inhibited in fermented preparation-treated rat platelets compared to that in non-fermented preparation-treated ones. We concluded that fermented preparations exerted more potent effects on platelet function both in vitro and ex vivo, possibly as a result of the increased bioavailability of active compounds produced during fermentation. We therefore suggest that fermented products may be potent therapeutics against platelet-related CVDs and can be used as antiplatelet and antithrombotic agents.

• Natural Product Sciences
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• v.26 no.4
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• pp.295-302
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• 2020

Cudrania tricuspidata (C. tricuspidata) is a deciduous tree found in Japan, China and Korea. The root, stems, bark and fruit of C. tricuspidata has been used as traditional herbal remedies such as eczema, mumps, acute arthritis and tuberculosis. In this study, we investigated the potential efficacies of this natural compound by focusing on the inhibitory effect of cudraxanthone L (CXL) isolated from the roots of C. tricuspidata on human platelet aggregation. Our study focused on the action of CXL on collagen-stimulated human platelet aggregation, inhibition of platelet signaling molecules such as fibrinogen binding, intracellular calcium mobilization, fibronectin adhesion, dense granule secretion, and thromboxane A2 secretion. In addition, we investigated the inhibitory effect of CXL on thrombin-induced clot retraction. Our results showed that CXL inhibited collagen-induced human platelet aggregation, intracellular calcium mobilization, fibrinogen binding, fibronectin adhesion and clot retraction without cytotoxicity. Therefore, we confirmed that CXL has inhibitory effects on human platelet activities and has potential value as a natural substance for preventing thrombosis.

• Applied Microscopy
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• v.17 no.2
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• pp.1-22
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• 1987

Pemphigus vulgar교의 본태(本態)를 알아보기 위한 일환으로 본질병(本疾病)의 병변조직(病變組織)을 전자현미경적(電子顯微鏡的)으로 관찰(觀察)하고 본질병(本疾病)에 관여(關與)하는 세포(細胞)들에 대(對)해 면역전자현미경적(免疫電子顯微鏡的)으로 추구(追究)하였던 바, 그 결과(結果)를 보고(報告)하는 바이다. 견(犬)의 pemphigus vulgaris의 구강(口腔) 및 식도(食道)의 점막층(粘膜層)을 전자현미경적(電子顯微鏡的)으로 관찰(觀察)하였던 바 acantholysis를 일으켜도 desmosome과 기저막(基底膜)은 큰 변화(變化)가 없었으며 세포간(細胞間)은 세포간물질(細胞間物質)의 집적(集積)에 의(依)해 확장(擴張)되고 이들 세포간강물질(細胞間腔物質)은 집괴(集塊) 또는 무구조(無構造)한 물질(物質)로 나타났다. 그리고 기저세포(基底細胞)는 기저막(基底膜)에 단단히 부착(附着)되어 있었고 dendritic cell이 기저세포층(基底細胞層)위로 분포(分布)되어 있었으며, 이들 dendritic cell 중(中)에서는 가끔 여러 형태(形態)의 퇴행성변화(退行性變化)를 볼 수 있었다. Mouse 피부유리상피세포(皮膚遊離上皮細胞)에 있어서 immunogold-labeling 방법(方法)에 의해 dendritic cell을 동정(同定)하는 데에는 post-fixation, pre-embedding immunogold-labeling technique가 좋았으며 15nm와 40nm 크기의 colloid-fold 입자(粒子)로 Langerhans cell과 Thy-1양성(陽性) dendritic cell이 표식(標識)될 수 있었다. 이들 세포(細胞)들은 세포막항원(細胞膜抗元)에 따라 monoclonal antibody의 반응(反應)에 이어 치밀한 colloid-gold 입자(粒子)가 세포막표면(細胞膜表面)을 따라 일정(一定)하게 표식(標識)되었다. 또한 이들 상피세포(上皮細胞)들을 투과전자현미경적(透過電子顯微鏡的)으로 관찰(觀察)하였을 때 초미세구조(超微細構造)가 잘 보존(保存)되었으나 Langer-hans cell내(內)의 Birbeck granule은 유리전(遊離前) 피부상피조직내(皮膚上皮組織內)의 Langerhans cell내(內)의 Birbeck granule에 비(比)해 수적(數的)으로 현저히 감소(減少)되어 있었다. 그러나 Thy-1 양성(陽性) dendritic cell에서 볼 수 있는 dense-core 과립(顆粒)은 별변화(別變化)없이 쉽게 관찰(觀察)될 수 있었다. 조직배양(組織培養)을 한 견(犬)의 keratinocyte에 대(對)해 사람 pemphigus vulgaris의 항체(抗體)로 반응(反應)시킨 후 protein-A gold(15 nm)로 표식(標識)시킨 바 제일 바깥 상층(上層)의 keratinocyte에 있어서 세포막표면(細胞膜表面)을 따라 표식(標識)되어 세포막항원(細胞膜抗元)을 나타내었으며, 이와 같은 소견(所見)으로 미루어 정상피부(正常皮膚) 중층편평상피세포(重層扁平上皮細胞)에서도 동일(同一)한 소견(所見)을 관찰(觀察)할 수 있다고 본다.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11c
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• pp.2119-2122
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• 2002

기업의 비즈니스 프로세스가 복잡, 다양해짐에 따라, 현재 운영 시스템에 대한 급격한 기술적 변화를 수용하고 이를 조직적 측면의 기업 프로세스로 적용하기 위해 레가시 시스템의 현대화가 요구된다. 따라서, 현재의 기업들은 다양한 사용자들이 각자 그들의 관점에서 필요한 비즈니스 요구들을 웹 상에서 처리시킬 수 있도록 J2EE, .NET 등으로 대표되는 컴포넌트 및 웹 서비스 기술을 적용한 새로운 e-business 환경을 수용해야만 한다. 하지만, 기업 조직의 중요한 지식과 프로세스들을 처리하는 시스템들은 대부분 과거(Legacy)의 기술에 의해 개발되어졌으며, 이러한 시스템들을 새로운 비즈니스 환경에 적용하기에는 웹 환경을 위한 분산 아키텍쳐의 결여와 개방성과 표준화 미흡으로 시스템의 유지보수에 많은 어려움을 가진다. 또한, 방법론 차원에서 재공학의 절차와 기법을 체계적으로 정의하고 지원하기 위한 노력이 매우 부족한 실정이다. 본 논문에서는 레거시 시스템을 새로운 시스템 환경으로의 변환 및 통합을 위한 재공학 방법론 개발을 목적으로 프로그램 분석 활동을 설명한다. 본 논문에서 개발하고자 하는 방법론은 다양한 추상화 수준에서 역공학 정보를 복구하고, 컴포넌트화 단계를 통해 새로운 시스템으로 진화할 수 있는 절차 및 기법들을 제공한다. 레거시 시스템 컴포넌트화 방법론은 변환계획 단계, 역공학 단계, 컴포넌트화 단계, 인도 단계의 4 단계로 구성되어 있으며, 본 논문에서는 전체 단계 중 가장 기초가 되고 중요한 단계인 역공학 단계에 초점을 두고 프로그램 분석을 위한 절차 및 과정의 주요 지침들을 제시한다.0보다 유의적으로 우수하였으며, 맛, 다즙성 및 전체적인 기호도는 TMR-0 및 TMR-1 사이에 유의성이 없었다(p<0.05).能性)을 알아보고자 본(本) 실험(實驗)을 실시(實施)한 결과(結果), 유의성(有意性) 있는 결과(結果)를 얻었기에 보고(報告)하는 바이다.또한 이들 상피세포(上皮細胞)들을 투과전자현미경적(透過電子顯微鏡的)으로 관찰(觀察)하였을 때 초미세구조(超微細構造)가 잘 보존(保存)되었으나 Langer-hans cell내(內)의 Birbeck granule은 유리전(遊離前) 피부상피조직내(皮膚上皮組織內)의 Langerhans cell내(內)의 Birbeck granule에 비(比)해 수적(數的)으로 현저히 감소(減少)되어 있었다. 그러나 Thy-1 양성(陽性) dendritic cell에서 볼 수 있는 dense-core 과립(顆粒)은 별변화(別變化)없이 쉽게 관찰(觀察)될 수 있었다. 조직배양(組織培養)을 한 견(犬)의 keratinocyte에 대(對)해 사람 pemphigus vulgaris의 항체(抗體)로 반응(反應)시킨 후 protein-A gold(15 nm)로 표식(標識)시킨 바 제일 바깥 상층(上層)의 keratinocyte에 있어서 세포막표면(細胞膜表面)을 따라 표식(標識)되어 세포막항원(細胞膜抗元)을 나타내었으며, 이와 같은 소견(所見)으로 미루어 정상피부(正常皮膚) 중층편평상피세포(重層扁平上皮細胞)에서도 동일(同一)한 소견(所見)을 관찰(觀察)할 수 있다고 본다.al remnants, Resorption of fetus로 관찰된 것이다. Fetal death는 수정후