• Applied Microscopy
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• v.14 no.2
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• pp.52-65
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• 1984

The ultrastructure of the pars distalis of the adenohypophysis was studied in the female Korean native goat ($10{\sim}16kg$, B.W.) by electron microscopy. Six granular cells and one agranular cell were recognized according to the characteristic patterns of secretory granules and cell organelles. Type I cells were. large, round or oval and contained the largest granules of 290 to 490 nm in diameter, Their endoplasmic reticula were well developed and packed with parallel lamellae close to nuclear membrane. Type II cells were elongate or polygonal. They contained granules of 220 to 390 nm in diameter and well developed Golgi complex. Type III cells were round, oval or angular and contained granules of 150 to 300 nm in diameter. Their endoplasmic reticula were coarsely scattered among the granules and provided an intracellular compartment for segregation in groups. Type IV cells were oval or round and contained granules of 120 to 280 nm in diameter. Their endoplasmic reticula were arranged at one pole of cytoplasm. Type V cells were round or polygonal and contained small granules of 110 to 140 nm in diameter Their endoplasmic reticula were packed with regularly parallel lamellae. Type VI cells were stellate and irregular in shape and had cytoplasmic processes projecting between the neighboring cells. Their granules were less than 130 nm in diameter, the smallest among the cells of the pars distalis. Agranular cells had no granules or a few, if any. They were stellate or irregular in shape.

• Applied Microscopy
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• v.14 no.2
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• pp.66-80
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• 1984

The organic phosphorus compounds have been widely used as an insecticide, since toxicity of these compounds is especially drastic to the insects than to men and other mammals. The organic phosphates are rapidly hydrolized and hence have little cumulative and ecologic effects. However, due to their acute toxic effects organophosphate have recorded rather high fatalities in men and domestic animals. The organic phosphorus compounds are powerful inhibitors to the carboxylic esterase enzymes such as acetylcholinesterase and pseudocholinesterase. As a result of firm binding characteristics of phosphate radicals to the active sites of enzyme, the activities of these enzymes are inhibited by the organophosphates. The organophosphates such as diazinon is easily observed from skin, gastrointestinal tract, conjunctivas and respiratory tract, and it is converted to more toxic form during metabolism in the liver The present study was carried out in order to investigate the hepatotoxicity of diazinon by observing the changes in the ultrastructure of cytoplasmic organelles of hepatic cells in albino mice. The animals were killed at 6, 12 and 24 hours after administration of 25mg/kg diazinon. The piece of hepatic tissue obtained from each animal was ultrathinly sectioned. The specimens stained by uranyl acetate and lead citrate double contrast methods were observed with JEM model 100B electron microscope. The results obtained were as follows: 1) A prominent dilatation and sacculation of the cisternae of rough endoplasmic reticulum associated with detachment of membrane bound-ribosomes, and disaggregation of the free ribosomes were recognized. 2) The hypertrophy of the smooth endoplasmic reticulum associated with depletion of the glycogen particles was observed. 3) The atrophy of cisternae of Golgi complex was observed. 4) A large number of secondary lysosomes (autophagic vacuoles and residual bodies) were formed. Consequently it is suggested that diazinon would induce disorganization of the cytoplasmic organelles of hepatocytes in albino mice.

• Applied Microscopy
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• v.31 no.4
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• pp.325-331
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• 2001

Integumentary structures of the stone flounder, Karefus bicoloratus were examined by means of the light and transmission electron microscopy. Stratified epidermal layer consists of supporting cells, unicellular glands and granular cells. The epidermal layer could be classified into superficial, intermediated and basal layer by morphology and structure of the supporting cells . The cytoplasm of supporting cells is divided into cortex and medullar part. In the cortex microfilaments are well developed. Mucous cells of unicellular gland were observed in the superficial and intermediated layer of the epidermis. The mucous materials were identified as glycoprotein of neutral and carboxylated mucosubstance by histochemical methods. Club cell has well developed smooth endoplasmic reticula and Golgi complex in the cytoplasm. Granular cells were observed in the intermediated and basal layer, and the cytoplasm is occupied with membrane-bounded granules of electron dense. Three types of pigment cells could be distinguished with electron density of cytoplasmic inclusions. Nerve myelins were observed near the pigment cells.

• Applied Microscopy
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• v.23 no.1
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• pp.109-124
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• 1993

The prenatal development of thoracic spinal cord was studied by electron microscope in human embryos and fetuses ranging from 9mm to 260mm crown-rump length (5-30 weeks of gestational age). Ependymal cells in all fetal ages had conspicuous junctional complexes close to the lumen of the central canal into which microvilli and cilia projected. The ependymal cells contained numerous longitudinally arranged mitochondria, flattened cisternae of endoplasmic reticulum and Golgi complex. At 20 mm embryo, the floor and roof plates were composed of ependymoglial cells and undifferentiated neuroepithelial cells. The neuroepithelia of the sacral spinal cord were delineated from central medullary cord. By 100 mm fetus few undifferentiated neuroepithelial cells remained in the floor and roof plates. At 150 mm fetus, the whole central canal was formed by ciliated columnar epithelial cells containing cilia with basal bodies. The microvilli became tangled and club-shaped and formed a matted surface. The canal was filled with areas of dark and pale amorphous materials bounded by membrane-like structure. These two types of material were found throughout the whole central canal from 100 mm fetus onwards. By 260 mm fetus, microfibrils were first observed in the ependymal cells. In conclusion, it seems that early development and differentiation of central canal ependyma are simlar to that in other part of the brain ventricular system although ependymoglial cells are more prominent.

• The Korean Journal of Malacology
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• v.27 no.3
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• pp.159-165
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• 2011

The anatomy and ultrastructure of the digestive diverticulum of Saxidomus purpuratus were described using light and electron microscopy. The digestive diverticulum of dark green color was situated on the gonad and connected to stomach by a primary duct. Digestive diverticulum is composed of numerous digestive tubules. The epithelial layer of digestive tubule, which is simple, is composed of basophilic cells and digestive cells. Basophilic cells are columnar in shape, and the electron density is higher than that of the digestive cell. The cytoplasm has a well-developed endoplasmic reticulum, tubular mitochondria, Golgi complex and membrane-bounded granules of high electron density. Digestive cells are columnar in shape, with development of microvilli on the free surface. Pinocytic vasicles, lysosomes and numerous mitochondria were observed in the apical cytoplasm of digestive cells. The results of this study suggest that basophilic cells and digestive cells in the digestive tubule are specialized in the extracellular and intracellular digestions, respectively.

• Biomolecules & Therapeutics
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• v.22 no.4
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• pp.275-281
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• 2014

Autophagy is a series of catabolic process mediating the bulk degradation of intracellular proteins and organelles through formation of a double-membrane vesicle, known as an autophagosome, and fusing with lysosome. Autophagy plays an important role of death-survival decisions in neuronal cells, which may influence to several neurodegenerative disorders including Parkinson's disease. Chebulagic acid, the major constituent of Terminalia chebula and Phyllanthus emblica, is a benzopyran tannin compound with various kinds of beneficial effects. This study was performed to investigate the autophagy enhancing effect of chebulagic acid on human neuroblastoma SH-SY5Y cell lines. We determined the effect of chebulagic acid on expression levels of autophagosome marker proteins such as, DOR/TP53INP2, Golgi-associated ATPase Enhancer of 16 kDa (GATE 16) and Light chain 3 II (LC3 II), as well as those of its upstream pathway proteins, AMP-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR) and Beclin-1. All of those proteins were modulated by chebulagic acid treatment in a way of enhancing the autophagy. Additionally in our study, chebulagic acid also showed a protective effect against 1-methyl-4-phenylpyridinium ($MPP^+$) - induced cytotoxicity which mimics the pathological symptom of Parkinson's disease. This effect seems partially mediated by enhanced autophagy which increased the degradation of aggregated or misfolded proteins from cells. This study suggests that chebulagic acid is an attractive candidate as an autophagy-enhancing agent and therefore, it may provide a promising strategy to prevent or cure the diseases caused by accumulation of abnormal proteins including Parkinson's disease.

• Molecules and Cells
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• v.40 no.11
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• pp.828-836
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• 2017

Eukaryotic cells consist of a complex network of thousands of proteins present in different organelles where organelle-specific cellular processes occur. Identification of the subcellular localization of a protein is important for understanding its potential biochemical functions. In the post-genomic era, localization of unknown proteins is achieved using multiple tools including a fluorescent-tagged protein approach. Several fluorescent-tagged protein organelle markers have been introduced into dicot plants, but its use is still limited in monocot plants. Here, we generated a set of multicolored organelle markers (fluorescent-tagged proteins) based on well-established targeting sequences. We used a series of pGWBs binary vectors to ameliorate localization and co-localization experiments using monocot plants. We constructed different fluorescent-tagged markers to visualize rice cell organelles, i.e., nucleus, plastids, mitochondria, peroxisomes, golgi body, endoplasmic reticulum, plasma membrane, and tonoplast, with four different fluorescent proteins (FPs) (G3GFP, mRFP, YFP, and CFP). Visualization of FP-tagged markers in their respective compartments has been reported for dicot and monocot plants. The comparative localization of the nucleus marker with a nucleus localizing sequence, and the similar, characteristic morphology of mCherry-tagged Arabidopsis organelle markers and our generated organelle markers in onion cells, provide further evidence for the correct subcellular localization of the Oryza sativa (rice) organelle marker. The set of eight different rice organelle markers with four different FPs provides a valuable resource for determining the subcellular localization of newly identified proteins, conducting co-localization assays, and generating stable transgenic localization in monocot plants.

• Applied Microscopy
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• v.13 no.1
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• pp.13-30
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• 1983

[ $1-{\beta}-D-Arabinofuranosylcytosine$ ](ara-C), which is a pyrimidine nucleoside analog is cytotonic to mammalian cells in culture and is active in vitro and in vivo against a variety of DNA viruses. The precise mechanism of action of ara-C has not been determined, although ara-C is thought to act as an antimetabolite, interfering with the synthesis of deoxyribonucleic acid(DNA). Cytosine arabinoside originally seemed to act principally by inhibiting the conversion of cytidine to deoxytidine, thus inhibiting DNA synthesis. But recent data suggest that effects upon DNA polymerase and effects via incorporation into DNA and RNA may well be of equal importance. The author have demonstrated the effect of cytosine arabinoside on the hepatocytes of albino mice treated with ara-C, observing changes in the cytoplasmic organelles of the hepatocytes. A total of 120 healthy male albino mice were divided into the control and ara-C treated groups. The animals of the ara-C group were given 10mg. per kg of body weight of mouse ara-C in physiological saline solution and the animals of control group were given physiological saline solution, intraperitoneally. After an administration of ara-C or physiological saline solution, the animal were killed at. interval of 6, 12, and 24 hours. The specimens, which were obtained from the left anterier lobe of the liver, were stained with uranyl acetate and lead citrate and observed with JEM 100B electron microscope. The results were obtained as follow: A pronounced dilatation, sacculation and fragmentation of the cisterane of rough endoplasmic reticulum with dissociation of membrane bound-ribosomes, disaggregation of free ribosomes in the cytoplasm, proliferation of the smooth endoplasmic reticulum associated with depletion of glycogen paracles, atrophies of Golgi complex, production of numerous lipid droplets, and formation of antophagic vacuoles, multivesicular bodies and residual bodies are recognized in the hepatocytes of ara-C treated mice. Consequently it is suggested that cytosine arabinoside would induce a changes of the cytoplasmic organelles of the hepatocytes in albino mice.

• Applied Microscopy
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• v.41 no.4
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• pp.257-263
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• 2011

The microanatomy and ultrastructure of the digestive diverticulum of Mytilus galloprovincialis were described using light and electron microscopy. The digestive diverticulum of tawny color was surrounded the stomach and connected to stomach by a primary duct. Digestive diverticulum is composed of numerous digestive tubules. The epithelial layer of a simple digestive tubule, which is simple, is composed of basophilic cells and digestive cells. Basophilic cells are columnar in shape, and has a well-developed endoplasmic reticula, tubular mitochondria, Golgi complex and membrane-bounded granules of high electron density in the cytoplasm. Whereas digestive cells are columnar in shape, with development of microvilli and cilia on the free surface. Pinocytic vasicles, active lysosomes and numerous mitochondria were observed in the apical cytoplasm of digestive cells. The results of this study suggest that basophilic cell and digestive cell of the digestive tubule are specialized in the extracellular and intracellular digestion, respectively.

• Applied Microscopy
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• v.28 no.1
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• pp.73-82
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• 1998

To elucidate how microfilaments and vesicles participate in bile formation, the pericanalicular cytoplasms were observed in the liver of rats treated with taurocholic acid by deep etching with rapid freezing, and copmpared them with the findings on convensional thin sections. The microfilaments were identified around the bile canaliculi in the forms of core filaments of microvilli, filaments of pericanalicular web running in parallel to the border of bile canaliculi, and filaments on the junctional complex. In taurocholic acid-treated rats, microfilaments could be visualized around the bile canaliculi and along their borders. The microfilaments appeared to be installed to link to both the canalicular membrane and vesicles. Such specialized microfilaments are considered to participate in the translocation of vesicles in the pericanalicular cytoplasm. From the evidence, it is assumed that the microfilament induces the vesicles to transport and fuse to bile canalicull into which bile acids is secreted by exocytosis.