• Journal of Microbiology and Biotechnology
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• 제11권3호
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• pp.458-462
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• 2001

The localization of paclitaxel was investigated in suspension culture cells of Taxus chinensis. Over 93% of the cell-associated paclitaxel were detected throughout the entire culture period. Intracellular localization of paclitaxel over the culture time was analyzed further by cell fractionation for days 21 and 42. Paclitaxel contents in intracellular organelles were decreased at day 42, while the content in the cell wall fraction was increased at day 42 compared to the value for day 21. The localization of paclitaxel in the cell wall was confirmed by using the immunocytochemical method with the aid of a confocal laser scanning microscope.

• 한국수산과학회지
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• 제33권2호
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• pp.148-152
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• 2000

베도라치의 피부는 크게 상피층과 진피층으로 구분된다. 상피층은 지지세포와 선세포들로 구성된다. 지지세포는 표면세포, 중간세포 및 기저세포로 구분되며, 선세포는 점액분비세포와 곤봉랑 세포로 구분된다. 지지세포들의 세포질은 피질부와 수질부로 나누어지는데, 수질부에는 세포소기관의 발달이 현저하며, 피질부에는 미세섬유의 발달이 뚜렷하다. 표면세포는 입방형이며 핵은 말굽형이다. 중간세포는 불규칙한 형태의 핵을 가지며, 핵과 세포질의 전자밀도는 지지세포 가운데 가장 높다. 기저세포는 원주형이나 핵은 세포질의 위쪽에 위치한다. 점액분비세포의 세포질은 타원형의 분비과립이 대부분을 차지하며, AB-PAS에 적색으로 반응하였다. 조면소포체와 골지체가 발달되어 있다. 곤봉상 세포의 세포질 상부에는 원형의 분비성 물질들이 차지하며, 핵은 장방형이고, 세포질에서는 조면소포체와 활면소포체가 발달되어 있다. 색소세포는 세포질에 전자밀도가 높은 색소과립들을 함유한 종류와 반사소판을 함유한 종류로 구분된다. 섬유세포의 세포질은 아주 잘 발달된 조면소포체들이 대부분을 차지한다.

• 대한한방내과학회지
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• 제41권1호
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• pp.44-58
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• 2020

Objectives: This study was conducted to identify the protective effects of Chongmyunggongjin-dan (CMGJD) on Hydrogen peroxide (H₂O₂)-induced apoptosis mechanisms in C6 glial cells. Method: We used CMGJD after distilled water extraction, filtration, and lyophilization. The ROS scavenging effect was examined by fluorescence microscopy. Expression levels of proteins related to ROS generation were investigated by western blotting. Functional changes in organelles related to Reactive oxygen species (ROS) generation were investigated by immunoblotting and by verifying expression level of relevant enzymes. Results: The CMGJD extract protected the cells against H₂O₂-induced morphological changes and DNA fragmentation, inhibited the increase of Heme_oxygenase-1(HO^-1) and the decrease in catalase, protected against the loss of mitochondrial membrane potential, inhibited disturbances of lysosomal function, and induced an increase in peroxisomes. Conclusion: CMGJD was confirmed to have a protective effect on H₂O₂-induced C6 glial cell death possibly by blocking the pathways causing damage to subcellular organelles, such as mitochondria, lysosomes, and peroxisomes. We assume that CMGJD will be effective for the prevention and treatment of ischemic stroke in a clinical environment.

• The Plant Pathology Journal
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• 제19권2호
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• pp.85-91
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• 2003

Pre-treatment with DL-3-aminobutyric acid (BABA) in the cucumber plants caused the decrease of disease severity after inoculation with anthracnose pathogen Colletotrichum orbiculare. In this study, ultrastructures of the vascular bundle and the infection structures in the leaves of BABA-treated as well as untreated cucumber plants were observed after inoculation with the anthracnose pathogen by electron microscopy. The ultrastructures of vascular bundle in the leaves of BABA-treated plants were similar to those of the untreated plants except plasmodesmata. In the BABA-treated plants, the plasmodesmata were more numerous than in the untreated plants, suggesting that the BABA treatment may cause the active transfer of metabolites through the vascular bundle. In the leaves of untreated plants, the fungal hyphae were spread widely in the plant tissues at 5 days after pathogen inoculation. Most cellular organelles in the hyphae were intact, indicating a compatible interaction between the plant and the parasite. In contrast, in the leaves of BABA pre-treated plants the growth of most hyphae was restricted to the epidermal cell layer at 5 days after inoculation. Most hyphae cytoplasm and nucleoplasm was electron dense or the intracellular organelles were degenerated. The cell walls of some plant cells became thick at the site adjacent to the intercellular hyphae, indicating a mechanical defense reaction of the plant cells against the fungal attack. Furthermore, hypersensitive reaction (HR) of the epidermal cells was often observed, in which the intracellular hyphae were degenerated. Based on these results it is suggested that BABA causes the enhancement of defense mechanisms in the cucumber plants such as cell wall apposition or HR against the invasion of C. orbiculare.

• ALGAE
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• 제35권4호
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• pp.389-404
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• 2020

Red algal fertilization is unusual and offers a different model to the mechanism of intracellular transport of nuclei and polyspermy blocking. A female carpogonium (egg) undergoes plasmogamy with many spermatia (sperm) simultaneously at the receptive structure, trichogyne, which often contains numerous male nuclei. The pattern of selective transport of a male nucleus to the female nucleus, located in the cell body of the carpogonium, remain largely unknown. We tracked the movement of spermatial nuclei and cell organelles in the trichogyne after plasmogamy using time-lapse videography and fluorescent probes. The fertilization process of Bostrychia moritziana is composed of five distinctive stages: 1) gamete-gamete binding; 2) mitosis in the attached spermatia; 3) formation of a fertilization channel; 4) migration of spermatial nuclei into the trichogyne; and 5) cutting off of the trichogyne cytoplasm from the rest of the cell after karyogamy. Our results showed that actin microfilaments were involved in the above steps of fertilization, microtubules are involved only in spermatial mitosis. Time-lapse videography showed that the first ("primary") nucleus which entered to trichogyne moved quickly to the base of carpogonium and fused with the female nucleus. The transport of the primary male nucleus to the egg nucleus was complete before its second nucleus migrated into the trichogyne. Male nuclei from other spermatia stopped directional movement soon after the first one entered the carpogonial base and oscillated near where they entered trichogyne. The cytoplasm of the trichogyne was cut off at a narrow neck connecting the trichogyne and carpogonial base after gamete nuclear fusion but gamete binding and plasmogamy continued on the trichogyne. Spermatial organelles, including mitochondria, entered the trichogyne together with the nuclei but did not show any directional movement and remained close to where they entered. These results suggest that polyspermy blocking in B. moritziana is achieved by the selective and rapid transport of the first nucleus entered trichogyne and the rupture of the trichogyne after gamete karyogamy.

• Applied Microscopy
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• 제28권3호
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• pp.283-297
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• 1998

Hemopoiesis and morphogenesis of the human fetal liver through from 10 to 32 weeks of gestation were investigated by light and electron microscopy. The results obtained were as follows. Hemopoiesis of fetal liver tissue was found from 10 to 32 weeks of gestation, but the hemopoiesis was decreased at 32 weeks of gestation. At the 32 weeks of gestation, matured erythrocytes were observed in the sinusoid, and formation of liver cell cord and portal triad were established. Differentiation of hepatic cell was characterized by the increase of amount of cell organelles within cytoplasm, decrease of hemopoietic cell, morphological change of nuclear envelope from folding form to round form during the developmental period. These results suggest that human fetal liver plays a hematopoietic function until bone marrow and spleen play their function, but morphology of liver at 32 weeks of gestation was differed with structure observed in liver of adult.

• Journal of Plant Biology
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• 제39권2호
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• pp.99-105
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• 1996

Immunocytochemistry utilizes the specificity of the antigen-antibody reaction to localize specific antigens in cells or cellular organelles. Here we report the use of monoclonal antibodies, in conjunction with gold-labeled second antibodies to study the ultrastructural localization and tissue distribution of the Mr 98, 000 anionic peroxidase and other wall antigens. The antibody specific for this wall peroxidase, mWP3, labeled mainly the cell wall area. At the tissue level, the Mr 98, 000 peroxidase is located predominantly in the leaf mesophyll, internal coleoptile and sieve elements, but not in the root, as assayed with these procedures. The coleoptile walls were less heavily stained than the walls of leaf mesophyll cells. At the subcellular level, it is localized mainly in intercellular regions of the cell walls. A similar staining pattern was revealed by mWP19, one of anti-$\beta$ glucosidase antibody, though it looked less heavily stained than one with mWP3. In order to serve as a control wall staining using IgM monoclonal antibodies, mWP18 was used. Most of the label is localized over wall regions of cells of the young leaf mesophyll and coleoptile.

• Anatomy and Cell Biology
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• 제57권2호
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• pp.155-162
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• 2024

Cerebral ischemia is the important cause of worldwide disability and mortality, that is one of the obstruction of blood vessels supplying to the brain. In early stage, glutamate excitotoxicity and high level of intracellular calcium (Ca²⁺) are the major processes which can promote many downstream signaling involving in neuronal death and brain tissue damaging. Moreover, autophagy, the reusing of damaged cell organelles, is affected in early ischemia. Under ischemic conditions, autophagy plays an important role to maintain energy of the brain and its function. In the other hand, over intracellular Ca²⁺ accumulation triggers excessive autophagic process and lysosomal degradation leading to autophagic process impairment which finally induce neuronal death. This article reviews the association between intracellular Ca²⁺ and autophagic process in acute stage of ischemic stroke.

• Applied Microscopy
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• 제39권2호
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• pp.185-189
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• 2009

초파리 망막 세포의 미세구조연구는 1960년대부터 수행되어 왔으나, 이 연구들은 2차원 구조연구에 국한되어 있었다. 본 논문은 초고압 동결법, 연속절편법, 초고압 전자현미경, 그리고 3차원 구조 구현법을 이용하여 초파리 성체의 망막 세포에 존재하는 미토콘드리아, 미세소관, 그리고 핵의 3차원 분포를 연구한 결과이다. 이를 통하여 미토콘드리아는 주로 세포막 가까이에 위치하며, 그 수는 렌즈와 가까운 말단부분에 많은 것을 알 수 있었고, 미세소관은 렌즈와 가까운 망막 말단부분과 시신경과 연결되는 기부에 특히 많은 수가 존재하는 것을 알 수 있었다. 이들은 망막 변성의 원인이 되는 세포 소기관이므로, 이들의 세포 내 3차원 분포는 병의 원인을 연구하는 데 있어 중요한 자료가 될 것으로 사료된다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2004년도 추계학술발표회 발표논문집
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• pp.1195-1196
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• 2004