• Title/Summary/Keyword: Cellular organelles

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A STUDY ON THE EFFECT OF INTERMAXILLARY FIXATION ON THE CHONDROCYTES OF RABBIT MANDIBULAR CONDYLE;A light and electron microscopic study (악간고정(顎間固定)이 가토(家兎)의 하악두(下顎頭) 연골세포(軟骨細胞)에 미치는 영향(影響)에 관(關)한 연구(硏究);광학현미경적(光學顯微鏡的) 및 전자현미경적(電子顯微鏡的) 연구(硏究))

  • Ryu, Dong-Mok;Kim, Yeo-Gab;Lee, Sang-Chul
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.11 no.1
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    • pp.130-152
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    • 1989
  • The purpose of this study was to observe the effect of intermaxillary fixation on the chondrocytes of the mandibular condyle under the light and the electron microscope. For this study, twenty rabbits were placed in maxillomandibular fixation, and two were used as a control group. The experimental group was subdivided into 3, 7, 14, 21 and 28 day group. After the experimental period of 3, 7, 14, 21 and 28 days, the animals were sacrificed with a vascular perfusion of 2.5% glutaraldehyde. The condylar processes were exenterated, and decalcified in 0.1M EDTA with 2.5% glutaraldehyde solution for two weeks. The specimens were rinsed with phosphate buffer solution and the post-fixation was carried out with 2% osmium tetroxide at $4^{\circ}C$ for two hours. Thereafter the specimens were dehydrated in alcohol series, cleared with propylene oxide and embedded in Epon 812 resin. Thin sections and ultra-thin sections were made, and the cellular structures of the condylar cartilages were observed with light and electron microscope. The results were as follows: 1. In the intermaxillary fixation group, the cartilaginous tissues of mandibular condyles showed a marked decrease in the thickness compared to the control group. 2. A remarkable change was noticed in the proliferating and the hypertrophic zone of the condylar cartilages in the experimental group. 3. An atrophic change of the condylar cartilage was appeared in the 3 day experimental group and degenerative change was observed in the 7 day experimental group, and recovery was seen in thereafter 14 day experimental group. 4. Calcification, degeneration and resorption of condylar cartilage were recognizable, and the cellular zone of the condylar cartilage was appeared indistinctly in 3 day and 7 day experimental group. The chondroblasts, however, were differentiated into chondrocytes and resumed mitosis, and then the cellular zones of the condylar cartilage were reorganized from the 14 day experimental group under the findings of light microscope. 5. Under the findings of electron microscope, atrophic changes and decrease in number of intracellular organelles, degenerative changes of cytoplasm, and pyknosis of nuclei were observed in early stage, however, a gradual regeneration and reorganization of the intracellular organelles were observed from 14 day experimental group.

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The primary cilium as a multiple cellular signaling scaffold in development and disease

  • Ko, Hyuk-Wan
    • BMB Reports
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    • v.45 no.8
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    • pp.427-432
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    • 2012
  • Primary cilia, single hair-like appendage on the surface of the most mammalian cells, were once considered to be vestigial cellular organelles for a past century because of their tiny structure and unknown function. Although they lack ancestral motility function of cilia or flagella, they share common ground with multiciliated motile cilia and flagella on internal structure such as microtubule based nine outer doublets nucleated from the base of mother centrioles called basal body. Making cilia, ciliogenesis, in cells depends on the cell cycle stage due to reuse of centrioles for cell division forming mitotic spindle pole (M phase) and assembling cilia from basal body (starting G1 phase and maintaining most of interphase). Ciliary assembly required two conflicting processes such as assembly and disassembly and balance between these two processes determines the length of cilia. Both process required highly conserved transport system to supply needed substance to grow tip of cilia and bring ciliary turnover product back to the base of cilia using motor protein, kinesin and dynein, and transport protein complex, IFT particles. Disruption of ciliary structure or function causes multiple human disorder called ciliopathies affecting disease of diverse ciliated tissues ranging from eye, kidney, respiratory tract and brain. Recent explosion of research on the primary cilia and their involvement on animal development and disease attracts scientific interest on how extensively the function of cilia related to specific cell physiology and signaling pathway. In this review, I introduce general features of primary cilia and recent progress in understanding of the ciliary length control and signaling pathways transduced through primary cilia in vertebrates.

Antioxidant enzymes as redox-based biomarkers: a brief review

  • Yang, Hee-Young;Lee, Tae-Hoon
    • BMB Reports
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    • v.48 no.4
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    • pp.200-208
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    • 2015
  • The field of redox proteomics focuses to a large extent on analyzing cysteine oxidation in proteins under different experimental conditions and states of diseases. The identification and localization of oxidized cysteines within the cellular milieu is critical for understanding the redox regulation of proteins under physiological and pathophysiological conditions, and it will in turn provide important information that are potentially useful for the development of novel strategies in the treatment and prevention of diseases associated with oxidative stress. Antioxidant enzymes that catalyze oxidation/reduction processes are able to serve as redox biomarkers in various human diseases, and they are key regulators controlling the redox state of functional proteins. Redox regulators with antioxidant properties related to active mediators, cellular organelles, and the surrounding environments are all connected within a network and are involved in diseases related to redox imbalance including cancer, ischemia/reperfusion injury, neurodegenerative diseases, as well as normal aging. In this review, we will briefly look at the selected aspects of oxidative thiol modification in antioxidant enzymes and thiol oxidation in proteins affected by redox control of antioxidant enzymes and their relation to disease. [BMB Reports 2015; 48(4): 200-208]

The involvement of oxygen free radicals in the onset of aging (노화에 미치는 산소 유리라디칼에 관한 연구동향)

  • Kim, Jung-Sang;Na, Chang-Su;Kim, Young-Kon
    • Korean Journal of Oriental Medicine
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    • v.3 no.1
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    • pp.229-239
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    • 1997
  • The superoxide anion radical$(O_2)$ poses a threat to macromocules and cell organelles of the living cells. This toxicity damage to all groups of proteins results in loss of enzyme function concerned with metabolism and ion transport, and peroxidation of unsaturated fatty acids and cholesterol results in a change of permeability characteristics of the membrane, and oxidative of nucleic acids results in genomic damage and thereby cause mutation, potential carcinogenesis and somatic damage that produce cellular aging Superoxide dismutase(SOD) has received substantial attention as a potential therapeutic agent. It has been investigated as a possible agent for the prevention of ontogenesis, the reduction of cytotoxic effect of anticancer drugs, and protection against damage in ischemic tissue. It is suggest that $O_2$ is concerned with cellular aging, thereafter we need to investigate herb that activated to SOD.

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Functions of the Plant Qbc SNARE SNAP25 in Cytokinesis and Biotic and Abiotic Stress Responses

  • Won, Kang-Hee;Kim, Hyeran
    • Molecules and Cells
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    • v.43 no.4
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    • pp.313-322
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    • 2020
  • Eukaryotes transport biomolecules between intracellular organelles and between cells and the environment via vesicle trafficking. Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE proteins) play pivotal roles in vesicle and membrane trafficking. These proteins are categorized as Qa, Qb, Qc, and R SNAREs and form a complex that induces vesicle fusion for targeting of vesicle cargos. As the core components of the SNARE complex, the SNAP25 Qbc SNAREs perform various functions related to cellular homeostasis. The Arabidopsis thaliana SNAP25 homolog AtSNAP33 interacts with Qa and R SNAREs and plays a key role in cytokinesis and in triggering innate immune responses. However, other Arabidopsis SNAP25 homologs, such as AtSNAP29 and AtSNAP30, are not well studied; this includes their localization, interactions, structures, and functions. Here, we discuss three biological functions of plant SNAP25 orthologs in the context of AtSNAP33 and highlight recent findings on SNAP25 orthologs in various plants. We propose future directions for determining the roles of the less well-characterized AtSNAP29 and AtSNAP30 proteins.

Ultrastructural Changes of Chinese Cabbage Root Tissues Associated with Pathogenesis of Plasmodiophora brassicae

  • Sung, Mi-Joo;Kim, Young-Soon;Kim, Young-Ho
    • The Plant Pathology Journal
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    • v.17 no.2
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    • pp.94-100
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    • 2001
  • Roots of Chinese cabbage (Brassica campestris var. chinensis) seedlings infected with Plasmodiophora brassicae were examined by light and electron microscopy to reveal histopathological changes related to pathogenesis in the susceptible host. The pathogen colonized the cortex and partly the stele as well, invading up to the xylem. Gall tissues could be differentiated from the initially infected tissues, involving less compact organization and new vascular development. The infected cells were much hypertrophied, and contained one to several plasmodia. Except cellular hypertrophy, no pathological ultrastructural modification was noted in the infected calls. Infected cytoplasm became dense with ground cytoplasm, inconspicuous central vacuole, and increased cellular organelles such as mitochondria and dictyosomes. There were two types of nuclear states of plasmodium, uninucleate and multinucleate. Both plasmodia were structurally similar, filled with lipid droplets, bounded with envelope, and containing mitochondria, endo-plasmic reticulum, and sometimes small vacuoles. Plasmodial fragmentation, which may be regarded as a way to discharge plasmodial materials into host cytoplasm, commonly occurred, forming plasmodial fragments by outgrowth of plasmodial cytoplasm and regional compartmentalization. Plasmodial fragments were degenerated sometimes followed by forming chains of spherical vesicles especially in the uninucleate plasmodial state. These ultrastructural features indicate the biotrophic nature of the pathogen associated with its pathogenesis in the susceptible host.

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Coordination chemistry of mitochondrial copper metalloenzymes: exploring implications for copper dyshomeostasis in cell death

  • Daeun Shim;Jiyeon Han
    • BMB Reports
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    • v.56 no.11
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    • pp.575-583
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    • 2023
  • Mitochondria, fundamental cellular organelles that govern energy metabolism, hold a pivotal role in cellular vitality. While consuming dioxygen to produce adenosine triphosphate (ATP), the electron transfer process within mitochondria can engender the formation of reactive oxygen species that exert dual roles in endothelial homeostatic signaling and oxidative stress. In the context of the intricate electron transfer process, several metal ions that include copper, iron, zinc, and manganese serve as crucial cofactors in mitochondrial metalloenzymes to mediate the synthesis of ATP and antioxidant defense. In this mini review, we provide a comprehensive understanding of the coordination chemistry of mitochondrial cuproenzymes. In detail, cytochrome c oxidase (CcO) reduces dioxygen to water coupled with proton pumping to generate an electrochemical gradient, while superoxide dismutase 1 (SOD1) functions in detoxifying superoxide into hydrogen peroxide. With an emphasis on the catalytic reactions of the copper metalloenzymes and insights into their ligand environment, we also outline the metalation process of these enzymes throughout the copper trafficking system. The impairment of copper homeostasis can trigger mitochondrial dysfunction, and potentially lead to the development of copper-related disorders. We describe the current knowledge regarding copper-mediated toxicity mechanisms, thereby shedding light on prospective therapeutic strategies for pathologies intertwined with copper dyshomeostasis.

Analysis of lysosomal membrane proteins exposed to melanin in HeLa cells

  • Bang, Seung Hyuck;Park, Dong Jun;Kim, Yang-Hoon;Min, Jiho
    • Environmental Analysis Health and Toxicology
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    • v.31
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    • pp.9.1-9.5
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    • 2016
  • Objectives There have been developed to use targeting ability for antimicrobial, anticancerous, gene therapy and cosmetics through analysis of various membrane proteins isolated from cell organelles. Methods It was examined about the lysosomal membrane protein extracted from lysosome isolated from HeLa cell treated by 100 ppm melanin for 24 hours in order to find associated with targeting ability to melanin using by 2-dimensional electrophoresis. Results The result showed 14 up-regulated (1.5-fold) and 13 down-regulated (2.0-fold) spots in relation to melanin exposure. Conclusions It has been found that lysosomal membrane proteins are associated with melanin to decolorize and quantity through cellular activation of lysosome.

The Ciliary Transition Zone: Finding the Pieces and Assembling the Gate

  • Goncalves, Joao;Pelletier, Laurence
    • Molecules and Cells
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    • v.40 no.4
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    • pp.243-253
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    • 2017
  • Eukaryotic cilia are organelles that project from the surface of cells to fulfill motility and sensory functions. In vertebrates, the functions of both motile and immotile cilia are critical for embryonic development and adult tissue homeostasis. Importantly, a multitude of human diseases is caused by abnormal cilia biogenesis and functions which rely on the compartmentalization of the cilium and the maintenance of its protein composition. The transition zone (TZ) is a specialized ciliary domain present at the base of the cilium and is part of a gate that controls protein entry and exit from this organelle. The relevance of the TZ is highlighted by the fact that several of its components are coded by ciliopathy genes. Here we review recent developments in the study of TZ proteomes, the mapping of individual components to the TZ structure and the establishment of the TZ as a lipid gate.

Roles of mitochondria in neuronal development

  • Son, Geurim;Han, Jinju
    • BMB Reports
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    • v.51 no.11
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    • pp.549-556
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    • 2018
  • Mitochondria are ubiquitous and multi-functional organelles involved in diverse metabolic processes, namely energy production and biomolecule synthesis. The intracellular mitochondrial morphology and distribution change dynamically, which reflect the metabolic state of a given cell type. A dramatic change of the mitochondrial dynamics has been observed in early development that led to further investigations on the relationship between mitochondria and the process of development. A significant developmental process to focus on, in this review, is a differentiation of neural progenitor cells into neurons. Information on how mitochondria-regulated cellular energetics is linked to neuronal development will be discussed, followed by functions of mitochondria and associated diseases in neuronal development. Lastly, the potential use of mitochondrial features in analyzing various neurodevelopmental diseases will be addressed.