• International Journal of Oral Biology
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• v.44 no.4
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• pp.144-151
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• 2019

Alopecia has emerged as one of the biggest interests in modern society. Many studies have focused on the treatment of alopecia, such as transplantation of hair follicles or inhibition of the androgen pathway. Hair growth is achieved through proper proliferation of the components such as keratinocytes and dermal papilla cells (DPCs), movement, and interaction between the two cells. The present study examined the effect of the hedgehog (Hh) signaling pathway, which is an important and fundamental signal in the cell, on the morphology and the viability of human keratinocytes and DPCs. Upregulation of Hh signaling caused a morphological change and an increase in epithelium-mesenchymal transition-related gene expression but reduced the viability of keratinocytes, while the alteration of Hh signaling did not cause any change in DPCs. The results show the possibility that the regulation of Hh signaling can be applied for the treatment of alopecia.

• Applied Microscopy
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• v.1 no.1
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• pp.19-26
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• 1969

Electron microscopy on the skin of young frogs, Rana temporaria, has been carried out with particular reference to cellular attachment sites. For the first time now several technical developments allow a more detailed visualization of the fine structure within the cellular attachment sites as well as making it possible to show the ultra-structural morphology of the junctional complexes, and to demonstrate that the desmosomes are regularly distributed aroand each skin cell, especially in the S. granulosum. The relations of these findings to these of previous investigations concerning the functional, organization of the junctional complexes and to the findings in skin cancer from a cellular adhesion view point have been briefly discussed.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.93-93
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• 2013

To make the rationale design of interface between cell and artificial surface, many studies have been controlled influencing cue which can typically be divided into two central categories: chemical cues based on modification surface chemical properties containing attractive/repulsive molecules, and physical cues that may include applied tension/stress, electrical polarization, magnetic field, and topography. Recently, researches have been focused on physical cue, especially topography. The surface topography may influence cellular responses for example, cell adhesion, cell morphology and gene expression. However, there were few systematic studies about these nanotopographical effects on neuronal developments in a feature size-dependent manner. Herein, we report a nanoscale-resolved study of nanotopographical effects on cellular adhesion and growth. In this study, we use substrates with packed glass beads by rubbing method for generating highly periodic nanotopographies with various sizes. We found that acceleration of neuritogenesis appeared only on the beads larger than 200 nm in diameter, and observed that filopodial thickness was comparable with this scale. This study is expected to be essential to elucidate the nanotopographical effect on cellular adhesion and growth.

• Korean Journal of Environmental Biology
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• v.28 no.2
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• pp.101-107
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• 2010

Metal ions are essential to life. However, some metals such as mercury are harmful, even when present at trace amounts. Toxicity of mercury arises mainly from its oxidizing properties. Ionizing radiation (IR) is an active tool for destruction of cancer cells and diagnosis of diseases, etc. IR induces DNA double strand breaks in the nucleus, In addition, it causes lipid peroxidation, ceramide generation, and protein oxidation in the membrane, cytoplasm and nucleus. Yeasts have been a commonly used material in biological research. In yeasts, the physiological response to changing environmental conditions is controlled by the cell types. Growth rate, mutation and environmental conditions affect cell size and shape distributions. In this work, the effect of IR and mercury chloride (II) on the morphology of yeast cells were investigated. Saccharomyces cerevisiae cells were treated with IR, mercury chloride (II) and IR combined with mercury chloride (II). Non-treated cells were used as a control group. Morphological changes were observed by a scanning electron microscope (SEM). The half-lethal condition from the previous experimental results was used to the IR combined with mercury. Yeast cells were exposed to 400 and 800 Gy at dose rates of 400Gy $hr^{-1}$ or 800 Gy $hr^{-1}$, respectively. Yeast cells were treated with 0.05 to 0.15 mM mercury chloride (II). Oxidative stress can damage cellular membranes through a lipidic peroxidation. This effect was detected in this work, after treatment of IR and mercury chloride (II). The cell morphology was modified more at high doses of IR and high concentrations of mercury chloride(II). IR and mercury chloride (II) were of the oxidative stress. Cell morphology was modified differently according to the way of oxidative stress treatment. Moreover, morphological changes in the cell membrane were more observable in the frequently stress treated cells than the temporarily stress treated cells.

• Molecules and Cells
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• v.28 no.2
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• pp.93-98
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• 2009

A plant-specific gene was cloned from melon fruit. This gene was named downward leaf curling (CmDLC) based on the phenotype of transgenic Arabidopsis plants overexpressing the gene. This expression level of this gene was especially upregulated during melon fruit enlargement. Overexpression of CmDLC in Arabidopsis resulted in dwarfism and narrow, epinastically curled leaves. These phenotypes were found to be caused by a reduction in cell number and cell size on the adaxial and abaxial sides of the epidermis, with a greater reduction on the abaxial side of the leaves. These phenotypic characteristics, combined with the more wavy morphology of epidermal cells in overexpression lines, indicate that CmDLC overexpression affects cell elongation and cell morphology. To investigate intracellular protein localization, a CmDLC-GFP fusion protein was made and expressed in onion epidermal cells. This protein was observed to be preferentially localized close to the cell membrane. Thus, we report here a new plant-specific gene that is localized to the cell membrane and that controls leaf cell number, size and morphology.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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• pp.6633-6638
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• 2014

The Pharmacological potential, such as antioxidant, anti-inflammatory, and antibacterial activities of Portulaca oleracea (PO) and Petroselinum sativum (PS) extracts are well known. However, the preventive properties against hepatocellular carcinoma cells have not been explored so far. Therefore, the present investigation was designed to study the anticancer activity of seed extracts of PO and PS on the human hepatocellular carcinoma cells (HepG2). The HepG2 cells were exposed with $5-500{\mu}g/ml$ of PO and PS for 24 h. After the exposure, cell viability by 3-(4,5-dimethylthiazol-2yl)-2,5-biphenyl tetrazolium bromide (MTT) assay, neutral red uptake (NRU) assay, and cellular morphology by phase contrast inverted microscope were studied. The results showed that PO and PS extracts significantly reduced the cell viability of HepG2 in a concentration dependent manner. The cell viability was recorded to be 67%, 31%, 21%, and 17% at 50, 100, 250, and $500{\mu}g/ml$ of PO, respectively by MTT assay and 91%, 62%, 27%, and 18% at 50, 100, 250, and $500{\mu}g/ml$ of PO, respectively by NRU assay. PS exposed HepG2 cells with $100{\mu}g/ml$ and higher concentrations were also found to be cytotoxic. The decrease in the cell viability at 100, 250, and $500{\mu}g/ml$ of PS was recorded as 70%, 33%, and 15% by MTT assay and 63%, 29%, and 17%, respectively by NRU assay. Results also showed that PO and PS exposed cells reduced the normal morphology and adhesion capacity of HepG2 cells. HepG2 cells exposed with $50{\mu}g/ml$ and higher concentrations of PO and PS lost their typical morphology, become smaller in size, and appeared in rounded bodies. Our results demonstrated preliminary screening of anticancer activity of Portulaca oleracea and Petroselinum sativum extracts against HepG2 cells, which can be further used for the development of a potential therapeutic anticancer agent.

• Applied Microscopy
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• v.32 no.4
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• pp.329-337
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• 2002

The morphology and cellular characteristics of adventitious roots, viz aerial roots, in the epiphytic American Ivy were examined to reveal structural changes of the aerial root upon surface attachment. Immature aerial roots were composed of parenchyma cells with dense cytoplasm containing plastids, however, the upper and lower epidermis were not distinguished. At early development, electron-dense substances (EDS) were constituents of much of the aerial root tissue, but the distribution of EDS varied within the tissue. The deposits appeared most concentrated in the superficial cell layers, with lesser amounts in cell layers closer to the cortex. Electron micrographs revealed that EDS deposits were always found in the vacuole, and were mainly associated with the tonoplast. While most of them occurred in the vacuole as small spherical deposits adjacent to the tonoplast, some deposits were oddly shaped or larger in size. Many of the vacuoles eventually filled with EDS, but the EDS content in those vacuoles decreased substantially after initial attachment to the surface. When the vacuoles became almost empty, cells near the epidermis already exhibited irregularity in outline. Subsequent breakdown of cellular components took place in the cells while they were still attached to the surface. This study suggests the potential role of EDS as substances involved in the surface attachment of the plant, however, further studies must be conducted to reveal the nature of EDS and the effects of EDS storage within these vacuoles.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.259-269
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• 2012

Protein phosphatase 2A (PP2A), a family of serine/threonine protein phosphatases, plays an important role in balancing the phosphorylation status of cellular proteins for regulating diverse biological functions in eukaryotic organisms. Despite intensive studies in mammals, limited information on its role is available in filamentous fungi. Here, we investigated the functional roles of genes for a putative B' delta regulatory subunit (FgPP2AR) and a catalytic subunit (FgPP2AC) of PP2A in a filamentous ascomycete, Fusarium graminearum. Molecular characterization of an insertional mutant of this plant pathogenic fungus allowed us to identify the roles of FgPP2AR. Targeted gene replacement and complementation analyses demonstrated that the deletion of FgPP2AR, which was constitutively expressed in all growth stages, caused drastic changes in hyphal growth, conidia morphology/germination, gene expression for mycotoxin production, sexual development and pathogenicity. In particular, overproduction of aberrant cylindrical-shaped conidia is suggestive of arthroconidial induction in the ${\Delta}FgPP2AR$ strain, which has never been described in F. graminearum. In contrast, the ${\Delta}FgPP2AC$ strain was not significantly different from its wild-type progenitor in conidiation, trichothecene gene expression, and pathogenicity; however, it showed reduced hyphal growth and no perithecial formation. The double-deletion ${\Delta}FgPP2AR;{\Delta}FgPP2AC$ strain had more severe defects than single-deletion strains in all examined phenotypes. Taken together, our results indicate that both the putative regulatory and catalytic subunits of PP2A are involved in various cellular processes for fungal development in F. graminearum.

• The Journal of Advanced Prosthodontics
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• v.10 no.2
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• pp.147-154
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• 2018

PURPOSE. This study was performed to evaluate the osteogenic potential of 3mol% yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP) and niobium oxide containing Y-TZPs with specific ratios, new (Y,Nb)-TZPs, namely YN4533 and YN4533/Al20 discs. MATERIALS AND METHODS. 3Y-TZP, YN4533 and YN4533/Al20 discs (15 mm diameter and 1 mm thickness) were prepared and their average surface roughness ($R_a$) and surface topography were analyzed using 3-D confocal laser microscope (CLSM) and scanning electron microscope (SEM). Mouse pre-osteoblast MC3T3-E1 cells were seeded onto all zirconia discs and evaluated with regard to cell attachment and morphology by (CLSM), cell proliferation by PicoGreen assay, and cell differentiation by Reverse-Transcription PCR and Quantitative Real-Time PCR, and alkaline phosphatase (Alp) staining. RESULTS. The cellular morphology of MC3T3-E1 pre-osteoblasts was more stretched on a smooth surface than on a rough surface, regardless of the material. Cellular proliferation was higher on smooth surfaces, but there were no significant differences between 3Y-TZP, YN4533, and YN4533/Al20. Osteoblast differentiation patterns on YN4533 and YN4533/Al20 were similar to or slightly higher than seen in 3Y-TZP. Although there were no significant differences in bone marker gene expression (alkaline phosphatase and osteocalcin), Alp staining indicated better osteoblast differentiation on YN4533 and YN4533/Al20 compared to 3Y-TZP. CONCLUSION. Based on these results, niobium oxide containing Y-TZPs have comparable osteogenic potential to 3Y-TZP and are expected to be suitable alternative ceramics dental implant materials to titanium for aesthetically important areas.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.747-752
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• 2013

Oncostatin M (OSM) is a multifunctional cellular regulator acting on a wide variety of cells, which has potential roles in the regulation of gene activation, cell survival, proliferation and differentiation. Previous studies have shown that OSM can induce morphological and/or functional differentiation and maturation of many tumor cells. However, the action of OSM on the induction of differentiation of human hepatocellular carcinoma (HCC) has not been reported. Here, we investigated the effects of different concentrations of OSM on human HCC cell line SMMC-7721 growth, proliferation, cell cycling, apoptosis and differentiation in vitro. Cell growth was determined via MTT assay, proliferation by cell cycle analysis, apoptosis by flow cytometry, morphology by transmission electronic microscopy, and cell function by detection of biochemical markers. Our results demonstrated that OSM strongly inhibited the growth of SMMC-7721 cells in a dose-dependent manner, associated with decreased clonogenicity. Cell cycle analysis revealed a decreased proportion of cells in S phase, with arrest at G0/G1. The apotosis rate was increased after OSM treatment compared to the control. These changes were associated with striking changes in cellular morphology, toward a more mature hepatic phenotype, accompanied by significant reduction of the expression of AFP and specific activity of ${\gamma}$-GT, with remarkable increase in secretion of albumin and ALP activity. Taken together, our findings indicate that OSM could induce the differentiation and reduce cell viability of SMMC-7721 cells, suggesting that differentiation therapy with OSM offers the opportunity for therapeutic intervention in HCC.