• BMB Reports
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• 제33권6호
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• pp.448-453
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• 2000

In yeast the key gluconeogenic enzyme, fructose-1,6-bisphosphatase (FBPase), is selectively targeted from the cytosol to the lysosome (vacuole) for degradation when glucose starved cells are replenished with glucose. The pathway for glucose induced FBPase degradation is unknown. To identify the receptor-mediated degradation pathway of FBPase, we investigated the presence of the FBPase receptor on the vacuolar membrane by cell fractionation experiments and binding assay using vid mutant (vacuolar import and degradation), which is defective in the glucose-induced degradation of FBPase. FBPase sedimented in the pellets from vid24-1 mutant after centrifugation at $15,000{\times}g$ for 15 min, suggesting that FBPase is associated with subcellular structures. Cell fractionation experiments revealed that FBPase is preferentially associated with the vacuole, but not with other organelles in vid24-1. FBPase enriched fractions that cofractionated with the vacuole were sensitive to proteinase K digestion, indicating that FBPase is peripherally associated with the vacuole. We developed an assay for the binding of FBPase to the vacuole. The assay revealed that FBPase bound to the vacuole with a Kd of $2.3{\times}10^6M$. The binding was saturable and specific. These results suggest that a receptor for FBPase degradation exists on the vacuolar membrane. It implies the existence of the receptor-mediated degradation pathway of FBPase by the lysosome.

• 대한수의학회지
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• 제22권2호
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• pp.187-195
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• 1982

This paper dealt with the light microscopical and electron microscopical findings on the morphological changes of the liver of Korean native goat injected with toxin (culture filtrate) of Clostridium perfringens which was isolated from Korean native cattle died of acute Clostridium perfringens enterotoxemia. The results observed are summarized as follows. In the microscopical findings, hyperemia and minute hemorrhage of the liver parenchyma, dilatation of hepatic central vein and centrilobular necrosis of liver, cloudy swelling and hydropic degeneration of hepatic cells, and appearance of light eosinophilic granular bodies in the vacuoles were recognized. In the electron microscopical findings, appearance of pinocytotic vesicle (coated vesicle), fusion of these vesicles, formation of vacuole and accumulation of minute granular proteinous materials in the vacuole were observed in the hepatic cells. Decreased number of glycogen granules, swelling and destruction of mitochondria, proliferation of smooth-surfaced endoplasmic reticulum, enlargement of rough-surfaced endoplasmic reticulum, dispersal of thready agranular membranous structure and appearance of secondary lysosome were recognized in the hepatic cell cytoplasm.

• Applied Microscopy
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• 제24권1호
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• pp.41-58
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• 1994

The present studies were designed to determine the feasibility of using the rat tracheal epithelium as models for induction of aging. The ultrastructural and cytochemical changes of tracheal epithelium were investigated in rats at ages of five, twelve and twenty four months. Some major changes in the tracheal epithelium with advancing age were observed by electron microscopy. The results were summarized as fellow: 1. With the advance of age, lysosome, vacuole and multivesicular bodies were increased in number and numerous myelinoid bodies were observed in cytoplasm of ciliated cells. 2. In goblet cell, serous cell and brush cell lysosome and myelinoid bodies were increased in number with the advance of age, and an myelinoid bodies was often found within the secretory granule. 3. Cytochemical studies showed that acid phosphatase activities was observed in multivesicular bodies and lysosome, strong activities with the advance of age. And alkaline phosphatase activity are observed in microvilli, granule and lateral membrane of secretory granule cells, and strong activities with age. Consequently suggest that with the advance of age, tracheal epithelium show ultrastructural and cytochemical alteration of some kind of cell organelles in all kind of cell.

• BMB Reports
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• 제42권2호
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• pp.65-71
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• 2009

Autophagy, which is a process of self eating, has gained interest in the past decade due to its both beneficial and controversial roles in various biological phenomena. The discovery of autophagy genes (ATG) in yeast has led to focused research designed to elucidate the mechanism and regulation of this process. The role of autophagy in a variety of biological phenomena, including human disease, is still the subject of debate. However, recent findings suggest that autophagy is a highly regulated process with both beneficial and negative effects. Indeed, studies conducted using various model organisms have demonstrated that increased autophagy leads to an extended lifespan. Despite these findings, it is still unknown if all pathways leading to extended lifespan converge at the process of autophagy or not. Here, an overview of modern developments related to the process of autophagy, its regulation and the molecular machinery involved is presented. In addition, this review focuses on one of the beneficial aspects of autophagy, its role in lifespan regulation.

• Applied Microscopy
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• 제26권4호
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• pp.465-477
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• 1996

본 연구에서는 담즙산과 cholesterol 및 phospholipid가 흰쥐 간세포내 소기관에 미치는 영향을 조사하여 이들 담즙물의 수송기전을 알아 보고져 하였다. 정상군과 각 실험군에서 관찰된 Golgi장치는 거의가 cis side를 담세관으로 향하고 있었다. 각 실험군에서는 ER과 Golgi 장치 및 용해소체 등 소기관의 수적 증가, 소조의 팽대, budding 등이 관찰되었다. Dehydrocholic acid 투여군에서는 cis Golgi cistern의 선상 팽대을 많이 볼 수 있었는데 공포(vacuole)들은 담세관과 Golgi 장치사이에서 관찰되었으며 ER과 담세관 사이에서도 관찰할 수 있었다. Cholesterol 투여군과 Phosphotidylcholine 투여군에는 Golgi 장치의 모든 소조들이 팽대되어 있었으며 ER 유래의 공포와 용헤소체가 증가되어 있었는데 용해소체의 증가는 특히 cholesterol 투여군에서 현져하였다. 이상의 소견으로 미루어 담즙성분의 분비에 관여하는 주된 세포내 소기관은 ER과 Golgi 장치 및 용해소체로 추정된다. 그러나 dehydrocholic acid는 ER과 cis Golgi 소조 유래의 공포에 의해 분비되며 Cholesterol과 phosphatidylcholine은 ER에서 또는 trans Golgi 소조을 거친 후 용해소체를 통해서 배출될 것으로 추정되는데 특히 cholesterol은 용해소체를 통해서 빈번히 배출될 것으로 생각된다.

• Applied Microscopy
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• 제3권1호
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• pp.1-16
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• 1973

이질아메바와 치은아메바의 Gomori 뱀에 의한 acid phosphatase 활성의 분포상태를 조사하기 위하여 광학현미경과 전자현미경으로서 비교 관찰한 바 그 결과를 요약하면 다음과 같다. 1) Acid phosphatase 활성부위를 광학 현미경으로서 관찰한 바 이질아메바와 치은아메바간에 각별한 차이가 없으며, 세포막에서는 약한 양성반응을 보였고 세포질 내부의 구조물에서는 강한 반응을 나타냈다. 2) 전자현미경 소견으로는 이질아메바의 세포막상에는 전반적으로 약한 양성 반응이 나타났으며 세포막 소돌기에 해당하는 부위에 강한 양성반응이 관찰되었다. 치은아메바에 있어서는 세포막은 대체로 음성이었으나 세포막의 국한된 부분에서 강한 반응을 나타내는 것도 있었다. 3) 세포질내부의 acid phosphatase 활성분포는 이질아메바에 있어서는 lysosome양 구조물, 형질내망 식포등에 강한 양성반응이 나타났으며 식포에서는 각종 단계의 반응이 관찰되었다. 치은아메바에 있어서도 이질아메바에서 관찰된 반응이 거이 나타났으며 특히 식포내용물은 강한 양성반응이나 그 막은 음성인 것이 현저하게 관찰되었다. 4) 핵내의 acid phosphatase 활성은 이질아메바에는 대조군에 비해 차이가 없었으나 치은 아메바에서는 핵질내에서 과립상 양성 침착물이 관찰되었다.

• Applied Microscopy
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• 제12권2호
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• pp.35-44
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• 1982

The fat bodies of cabbage worm (Pieris rapae) and silk worm (Bomyx mori) during metamorphosis was comparatively studied by electron microscope. 1. Cell oranelles: Golgi apparatus were not observed in both species. It is observed that RER of cabbage worms initiate to degenerate in prepupa stage with complete degeneration at adult stage, while that of silk worms shows similar degenerative pattern. However, mitochondria of cabbage worms are transformed into autophagic vacuole from prepupa stage until adult stage whereas those of silk worm shows a decrease in number in prepupa stage but maintains a certain level until adult stage. 2. Storage substance in cell: Lipid droplets in cabbage worms were observed to increase in numbers during larval stage but afterward decrease in number with an enlargement in size. However immediately after their pupal stage, they almost disappear. On the contrary lipid droplets in silk worms show rather increase in number until adult stage. Protein storage granules in bothspecies were arised from autophagic vacuoles(lysosome) . Fat cells of cabbage worm in adult stage turn out to be residual bodies which last until final stage, but those of silk worm rapidly decrease. Glycogen particles in both species reach maximum at last larval instar and thee gradually decrease thereafter. 3. Fat body sheath: The average width of fat body sheath was measured to be $0.2{\mu}m$ and $0.6{\mu}m$ and surface of fat cells adjacent to fat body sheath in silk worm is heavily infolded.

• 한국콘텐츠학회논문지
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• 제10권7호
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• pp.297-304
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• 2010

소장 흡수상피 세포는 점액 다당류가 풍부하고 림프구와 사립체가 많아 방사선에너지에 민감하다. 따라서 세포 손상은 영양분 결핍 및 전해질 대사의 불균형을 가져와 장관사의 주 원인이 된다. 본 연구는 소장 흡수상피 세포들의 방사선 손상기전과 방어기작을 밝히고자 프로폴리스를 복강에 투여한 후 초 미세구조를 관찰하였다. 관찰 결과, 5Gy 조사 후 20일된 조직에서 소장이 유착되고, 표면이 검게 변해 있었으며 탄력성이 줄어든 것을 볼 수 있었다. 광학현미경(LM) 관찰 결과, 배상세포의 크기 및 수가 줄어들었으며 파네트과립세포는 위축되고 일부에서는 공포가 관찰되었다. 전자현미경(TEM) 관찰 결과, 미세융모와 용해소체는 정상적으로 관찰되었으나 사립체 막이 손상되고 림프구 가장자리에서 요철면이 형성되었다. 회장에서는 흡수상피조직이 비후되고 공포가 관찰되었다. 하지만 프로폴리스 복강 투여 후 관찰에서는 사립체의 이중막이 정상적으로 관찰되었고, 미세융모의 당질층도 손상되지 않았으며, M세포도 많이 관찰되어 자기소화와 흡수 기능이 원활하였다. 따라서 세균 바이러스 등의 면역기능과 세포 손상에 방어효과를 확인하였다.

• 한국패류학회지
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• 제27권3호
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• pp.213-221
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• 2011

TBTCl에 36주 동안 노출된 대복, Gomphina veneriformis 의 미세구조적인 변화를 전자현미경으로 관찰하였다. 대복의 외투막은 가장자리에 4개의 주름을 가지며, 내부와 외부상피층이 단층의 원주형 상피세포, 섬모세포, 분비세포로 구성되어 있었다. 이들 상피층은 혈림프동이 존재하는 결합조직층을 둘러싸고 있었다. 대복의 외투막은 TBTCl 노출 12주째 내부상피층에 존재하는 섬모의 수가 감소하였으며, 혈림프동의 확장과 함께 격막의 파괴가 관찰되었다. 노출 20주째 세포질내의 공포형성, 핵응축과 같은 변화가 관찰되었고, 결합조직층에서는 근섬유다발의 분절이 부분적으로 관찰되었다. 노출 28주째 상피층의 부분적인 붕괴, 섬모의 변화 및 섬모세포에 존재하는 미세구조가 괴사되었다. 결합조직층에 존재하는 다수의 근형질막은 팽창되었으며, 막의 내부에는 근섬유들이 대부분 파괴되어 막 주변에 근섬유 잔여물들이 관찰되었다. 노출 36주째에는 섬모들은 모두 탈락되고, 핵 응축되고, 이형소체의 증가가 나타나는 퇴행성 상피세포가 나타났다. 외부상피층의 상피세포들이 괴상되어 핵이 파괴되고, 세포질 내에는 다수의 용해소체들이 가득 차 있었으며, 미세융모들은 대부분 소실되었다. 따라서 만성적인 TBTCl 노출은 대복의 외투막은 각장성장 및 생리적인 기능의 장애를 유발하는 것으로 생각된다.

• 대한치과보철학회지
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• 제28권2호
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• pp.1-28
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• 1990

The severe atrophic edentulism with poor neuromuscular control militates against successful conventional denture therapy. To such situation, a prescribing of dental implant treatment has been considered with some probability. Implant materials used as a trial for dental implants includes metals, plastic polymers and ceramics. The purpose of this study was to observe histologic response in osseointegration process at titanium implant-tissue interface based on biocompatibility at specific period of sequential natures which were divided into a half month, one, month, two months, three months and immediate as a base line. In this study, unilateral lower left premolar and molar teeth were extraced in three dogs. After allowing to heal for 6 months, three kinds of osseointegrated implant, $Br{\aa}nemark$, Corevent and kimplant(a prototype of SNU implant study)were inserted in each dog respectively according to the above sequence from front to back. The specimens were taken from those dogs at the same time since implant were inserted quite reverse order of the specified periods, and decalcified and processed for histologic examination for the light microscopy and the electron microscopy. The microscopic histologic findings at the interface between titanium implants and tissue were interpretated as follows : A. Light microscopic findings : a. Immediate : Implant were surrounded by compact bone and spongy bone. Microcrak was observed in the superficial bone tissue. Osteocytes were disappeared and bone lacunae were observed as a vacant space in some parts. In the contacting with the spongy bone, bone trabeculae and bone marrow were in contact with the implant. b. A half Month : Osteoblasts exist as a monolayer in th inner bone trabeculae and do bone additiocn. Osteoblasts&inflammatory cells were observed in some parts. c. One Month : The presence of osteoclasts decreased. Osteoblasts did active bone fromation, and bone marrow was in contact with the implant in the many places. d. Two Months : Bone formation was advanced in comparison with the b and c. The presence of osteoclsts was not observed. e. Three Months : The superficial bone tissue contacted with the implants was entirely composed by the compact bone. B. Electron microscopic findings : a. A half month and one month group : In the parts of the active bone formation, osteoblasts with the well developed endoplasmic reticulum and Golgi apparatus were arranged in the monolayer. In the parts of the bone resorption, ruffled border was well developed and many osteoclasts with the well-developed golgi apparatus, mitochondria, vacuole, vesicle and lysosome were existed. b. Three months group : No osteoblasts were observed in the superficial bone tissue. Bone matrix with collaen fiber was observed. c. No significant dirrerence in the histologic findings was observed in $Br{\aa}nemark$, Core-vent and kimplant.