• Applied Microscopy
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• v.29 no.1
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• pp.57-66
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• 1999

The nervous tissue in the cerebral ganglion of Korean planaria was observed using electron microscope. The obtained results are as follows: A cerebral ganglion is composed of the nerve cells, neurosecretory cells, neuroglial cells and neuropils. The nerve cells are round or ovoidal-shaped cells (diameter, $5{\mu}m$), which has a large ellipsoidal nucleus containing the evenly developed heterochromatin. Their cytoplasms were found to be relatively simple, because of their undeveloped cell organelles. The neurosecretory cells are long and ellipsoid or spindle-shaped cells, where there were found a large ellipsoidal nucleus and cytoplasm filled with secretory granules (diameter, 60 nm). The neuroglial cells were seldom observed. They are spindle-shaped cells (size, $6\times0.8{\mu}m$), which were observed mainly among the nerve fibers. The neuropils are formed by the nerve fibers and nerve endings which are filled with mitochondria, neurotubules and secretory granules of four kinds (high electron dense granules of sizes 75 nm, 50 nm and 37 nm, and electron lucent granule of size 30 nm etc.). These granular vesicles are divided into single vesicle type and compound vesicle type in the nerve terminals, and neuronal synapses were observed to be the axo-dendritic and dendro-dendritic synapse type.

• The Korean Journal of Zoology
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• v.37 no.4
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• pp.531-537
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• 1994

Partial internal amino acid sequences of the 15S ATPase from chick skeletal muscle were determined and found to be identical to the corresponding regions of the Mg2+_ATPase from Xenopus laevis oocytes, that is a close homolog of N-ethvlmaleimide-sensitive factor (called NSF) in hamster and Sec18p in yeast, both of which are believed to plaN an essential role in vesicle fusion in secretory process. Thus, the 15S Arpase in chick skeletal muscle maw also belong to a protein family of the "vesicle fusion proteins". Unlike the Mg2'-Afpase with an isoelectric point (pl) of 5.5, however, the 15S Arpase was separated into four spots with pls of 4.9,6.4 and 6.9 upon analysis by twoiimensional gel electrophoresis. In addition, the anti-15S ATPase IgG was found to be capable of interacting with the 265 protease complex upon analysis by immunoprecipitation. Moreover, immunoblot analysis revealed that the anti-155 Arpase IgG recognizes three subunits, ko of which show the same mobilities as the 510-kDa subunit 4 and 48-kDa subunit 7 of the 26S protease complex that are known to contain a highly consented ATP-binding motif. These results surest that a common antigenic site, likely the consensus nucleotide-binding site, exists in the 15S ATPase and the 26S pretense complex and hence both the enzymes maw also be related ATPases.d ATPases.

• Molecules and Cells
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• v.46 no.4
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• pp.191-199
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• 2023

The Golgi apparatus modifies and transports secretory and membrane proteins. In some instances, the production of secretory and membrane proteins exceeds the capacity of the Golgi apparatus, including vesicle trafficking and the post-translational modification of macromolecules. These proteins are not modified or delivered appropriately due to the insufficiency in the Golgi function. These conditions disturb Golgi homeostasis and induce a cellular condition known as Golgi stress, causing cells to activate the 'Golgi stress response,' which is a homeostatic process to increase the capacity of the Golgi based on cellular requirements. Since the Golgi functions are diverse, several response pathways involving TFE3, HSP47, CREB3, proteoglycan, mucin, MAPK/ETS, and PERK regulate the capacity of each Golgi function separately. Understanding the Golgi stress response is crucial for revealing the mechanisms underlying Golgi dynamics and its effect on human health because many signaling molecules are related to diseases, ranging from viral infections to fatal neurodegenerative diseases. Therefore, it is valuable to summarize and investigate the mechanisms underlying Golgi stress response in disease pathogenesis, as they may contribute to developing novel therapeutic strategies. In this review, we investigate the perturbations and stress signaling of the Golgi, as well as the therapeutic potentials of new strategies for treating Golgi stress-associated diseases.

• Journal of Life Science
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• v.24 no.10
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• pp.1070-1077
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• 2014

In this study, the estrogen receptor agonist propyl pyrazole triol (PPT), which has high-affinity with the estrogen receptor alpha, was subcutaneously injected into adult male mice every 2 days for 8, 16 and 24 days, after which histological changes in accessory genital glands, including the prostate and seminal vesicle, and the liver were observed. The body and genital gland weights decreased in the PPT group relative to those of the control group. However, the liver weight was two times greater in the PPT group. The luminal area of the prostate and seminal vesicle organs was lower in the PPT group, and the epithelial cell height of the prostate was increased relative to that of the control. There were many secretory vacuoles in the supranuclear cytoplasm of epithelial cells in the seminal vesicles of the control group, but these were not observed in the PPT group. The short sinusoidal diameter of the liver was 147.0%, 198.7%, and 223.3% greater in the PPT group than in the control group after 8, 16, and 24 days of treatment, respectively. These results suggest that PPT administration affected the reproductive organs and the liver and that the histological changes increased in accordance with a rise in the concentration of PPT. Overall, the PPT treatment caused changes in the epithelial cell height and resulted in atrophy of the luminal area of the prostate, leading to altered fertility. The sinusoidal diameter of the liver dramatically increased in response to the administration of PPT, increasing the liver weight.

• Animal cells and systems
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• v.2 no.4
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• pp.501-506
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• 1998

In the goby Micropercops swinhonis, the development of its egg's enveloping layers could be divided into 4 stages. In the earliest developmental period, stage I, there is a simple oocyte surrounded by a layer of squamous follicular cells. Stage II corresponds to the yolk vesicle stage of vitellogenesis. Here the initial follicular layer has become bilaminar with the retention of its outer squamous cell layer and the acquisition of an inner cuboidal cell layer just over the zona radiata. The number and size of the cuboidal cells increases throughout this stage. Stage III corresponds to the yolk granule stage of true vitellogenesis. Here the cuboidal cells begin to be replaced by columnar cells. As the oocyte grows, the columnar cells increase in size. The columnar cells produce cytoplasmic neutral mucins and by the end of this stage their cytoplasm has been filled with this mucin. In stage IV a single layer of squamous cells still remained as the outer follicular layer of the oocyte. The secretory activity of the inner follicular layers' columnar cells has ceased and they had lost their cell wall integrity and ended as a series of bullet-shaped, neutral mucin deposits.

• Applied Microscopy
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• v.32 no.3
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• pp.265-273
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• 2002

The purpose of this study was to observe the influences of the water fluoride concentration on the growth changes, the histologic characteristics of osteoblast in the tibia of growing newborn rats by using electron microscopy and on the composition changes of bone matrix in those by using energy dispersive x-ray system (EDX). The water fluoride concentration was respectively 0 ppm (contrast group), 100 ppm (100 ppm group), 200 ppm (200 ppm group) and 300 ppm (300 ppm group). The results of the investigation by using electron microscopy were as followed. In contrast group, the traditional cuboidal osteoblasts were observed. In 100 ppm group, several reversal line, the newly formed osteoid by the strongly activated osteoblast and the well developed rough endoplasmic reticulum, mitochondria in cytoplasm of osteoblast were observed. Also, many secretory vesicle around cell membrane were observed and some fused with cell membrane released secretory granule out of cell. In 200 ppm group, the depressed osteoblasts were observed, mitochondria in cytoplasm were expanded and cristae shape in mitochondria were destroyed. Also, the ribosome at the surface of rough endoplasmic reticulum were not observed. In 300 ppm group, the adjacent osteoblasts with endosteum were irregularly arranged, the cell membrane were destroyed and organelles were flowed out of cell. On the other hand, the results of the investigation by using energy dispersive x-ray system were as followed. P and Ca concentrations in 100 ppm group were increased more than those in contrast group. But, in 200 and 300 ppm group were not increased more than those in 100 ppm group. Therefore, the activities of the osteoblasts were increased, the bone matrix were actively synthesized by the supplied water fluoride. But, the osteoblasts were destroyed, inhibited by the higher water fluoride concentration.

• Parasites, Hosts and Diseases
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• v.31 no.4
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• pp.301-314
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• 1993

An electron microscopic study was performed to observe the ultrastructure of the tegument of U seoulensis. The outer surface of the tegument was covered with a tnlaminated plasma membrane. The electron-dense cytoplasmic layer was $2.5{\;}\mu\textrm{m}$ wide In the anterior portion and contained numerous vacuoles, mitochondriae and granular materials in its matrix. The basement layer was 330 nm wade or so, and Its numerous extensions protruded into the cytoplasmic layer. The sensory organ was composed of a small vesicle of $1.7{\;}{\times}{\;}1.1{\;}\mu\textrm{m}$ in dimensions, which possessed a cilium of $1.2{\;}{\times}{\;}0.19{\;}\mu\textrm{m}$ in size. The pharynx was composed of the epithelial layer of about $0.5{\;}\mu\textrm{m}$ wide, well developed muscle layer and basement layer. The tegument of the oral sucker was composed of a cytoplasmic layer of $0.4-0.5{\;}\mu\textrm{m}$ width, a narrow basement layer, a well developed muscle layer and tegumental cells. Some kinds of secretory granules that seemed to be originated from the cells of the oral sucker were observed In the parenchymal portions of the adjacent cells. The tribocytic organ consisted of numerous microvilli. The microvilli were 5 nm wide and heptalaminated. Two types of secretory granules originated from the gland cells of tribocytic organ were observed In the tegument and parenchyme. The tegumental cells were irregular in shape, and of which nuclei were multifarious.

• Molecules and Cells
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• v.38 no.10
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• pp.866-875
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• 2015

COPI vesicles are essential to the retrograde transport of proteins in the early secretory pathway. The COPI coatomer complex consists of seven subunits, termed ${\alpha}-$, ${\beta}-$, ${\beta}^{\prime}-$, ${\gamma}-$, ${\delta}-$, ${\varepsilon}-$, and ${\zeta}$-COP, in yeast and mammals. Plant genomes have homologs of these subunits, but the essentiality of their cellular functions has hampered the functional characterization of the subunit genes in plants. Here we have employed virus-induced gene silencing (VIGS) and dexamethasone (DEX)-inducible RNAi of the COPI subunit genes to study the in vivo functions of the COPI coatomer complex in plants. The ${\beta}^{\prime}-$, ${\gamma}-$, and ${\delta}$-COP subunits localized to the Golgi as GFP-fusion proteins and interacted with each other in the Golgi. Silencing of ${\beta}^{\prime}-$, ${\gamma}-$, and ${\delta}$-COP by VIGS resulted in growth arrest and acute plant death in Nicotiana benthamiana, with the affected leaf cells exhibiting morphological markers of programmed cell death. Depletion of the COPI subunits resulted in disruption of the Golgi structure and accumulation of autolysosome-like structures in earlier stages of gene silencing. In tobacco BY-2 cells, DEX-inducible RNAi of ${\beta}^{\prime}$-COP caused aberrant cell plate formation during cytokinesis. Collectively, these results suggest that COPI vesicles are essential to plant growth and survival by maintaining the Golgi apparatus and modulating cell plate formation.

• Parasites, Hosts and Diseases
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• v.60 no.5
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• pp.309-315
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• 2022

Inflammatory bowel disease (IBD) is a chronic and recurrent illness of the gastrointestinal tract. Treatment of IBD traditionally involves the use of aminosalicylic acid and steroids, while these drugs has been associated with untoward effects and refractoriness. The absence of effective treatment regimen against IBD has led to the exploration of new targets. Parasites are promising as an alternative therapy for IBD. Recent studies have highlighted the use of parasite-derived substances, such as excretory secretory products, extracellular vesicles (EVs), and exosomes, for the treatment of IBD. In this report, we examined whether EVs secreted by Giardia lamblia could prevent colitis in a mouse model. G. lamblia EVs (GlEVs) were prepared from in vitro cultures of Giardia trophozoites. Clinical signs, microscopic colon tissue inflammation, and cytokine expression levels were detected to assess the effect of GlEV treatment on dextran sulfate sodium (DSS)-induced experimental murine colitis. The administration of GlEVs prior to DSS challenge reduced the expression levels of pro-inflammatory cytokines, including tumor necrosis factor alpha, interleukin 1 beta, and interferon gamma. Our results indicate that GlEV can exert preventive effects and possess therapeutic properties against DSS-induced colitis.

• Applied Microscopy
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• v.12 no.2
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• pp.69-79
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• 1982

In order to define the morphological changes of the secreting cells of prothoracic gland during larva-pupal molt, ultrastructural observations were carried out using Bombyx mori L. as the experimental material. At first stage of present experiment, 4 day old 5th instar larva, the polyhedral secreting cells were centrally located in the prothoracic gland surrounded by the connective sheath. The secreting cells were attached to the neighboring cells by the prominent desmosomes, and the plasma membrane contacted with connective sheath were highly infolded. In cytoplasm, the most of the cell organelles, such as rod-like mitochondria, rough surfaced endoplasmic reticulum, ribosome were developed. As the stages advance from larva to pupa, general feature of the secreting cells were retained, but structural changes of the various cytoplasmic organelles-ribosome, rough surfaced endoplasmic reticulum, mitochondria, Golgi apparatus, lamellar body, and vesicle-were noted. In the perinuclear cytoplasm of the secreting cells at the stage of 6 day old 5th instar larva, it is peculiar that only a large amount of ribosomes were distributed and the other organelles were retreated from the juxtanuclear region. Just before and after spining cocoon, these features were more remarkable. Rough surfaced endoplasmic reticulum were gradually increased from the stage just before spining cocoon to the pharate pupa. Rod-like mitochondria with irregular cristae and the matrix showing low density were distributed throughout the cytoplasm in the secreting cells of the 4 day old 5th instar larva. Sometimes, longitudinally distended and curved mitochondria were observed. At the stage of pharate pupa, most of mitochondria were deformed. The rod-like mitochondria of the secreting cells of pupal prothoracic gland were narrower than those of 4 day old 5th instar larva, and the electron density of the mitochondrial matrix is increased in pupa. Golgi apparatus were a few in number in both stages, last instar larva and spining cocoon. In stages of the pharate pupa, the Golgi apparatus were frequently observed. Cytoplasmic vesicles were observed for the first time in the secreting cells of one day after spining cocoon, and the number and the size of cytoplasmic vesicles were distinctly increased inpharate pupa and just after pupation. In the secretory cells of the PG, it in concluded that the RER was closely related to syntheting the enzymes seem to produce the ecdysone.