• Title/Summary/Keyword: cell morphology

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Cuticle Micromorphology of Korean Gymnosperms I. Cycadaceae, Ginkgoaceae, Taxaceae and Cephalotaxaceae

  • Sung Soo Whang
    • Journal of Plant Biology
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    • v.38 no.2
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    • pp.181-193
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    • 1995
  • Cuticle micromorphology of four families of Korean gymnosperms, Cycadaceae, Ginkgoaceae, Taxaceae, and Cephalotaxaceae, were studied with scanning electron microscopy. The outer and inner features of abaxial and adaxial cuticles were described in details; the absent or present of Florin ring, orifice, trichome, and plug and their shape, the shape and periclinal and anticlinal wall sculpture of epidermal cells, the shape of cuticular flange of epidermal cell, guard cell, and subsidiary cell, the number of stomatal bands and rows, and stomatal apparatus including the shape of polar extension, number of subsidiary cells, the sculpture of guard cell and subsidiary cell. Most of these features have not been sufficiently substantiated by the previous reprots. Furthermore, all the species investigated showed distinctive cuticle morphology with morphological and taxonomical informations.

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Preparation and Comparative Test of Polypyrrole Electrodes for Direct Methanol Fuel Cell

  • Park, Jae-Chan;Kim, Jeong-Soo;Jung, Doo-Hwan
    • Macromolecular Research
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    • v.10 no.4
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    • pp.181-186
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    • 2002
  • The displacement of carbon black to polypyrrole as a catalyst supporter in the fuel electrode of a direct methanol fuel cell was investigated. Polypyrrole was obtained as a black powder by the chemical polymerization of pyrrole with three different oxidants. The synthesized polypyrroles were pasted on carbon paper and transformed to the fuel electrodes with electrochemically deposited platinum. The prepared fuel electrode was assembled and mounted in a unit cell using a membrane and cathodic electrode film. In comparison with the carbon black fuel electrode, the performance of the unit cell was analyzed in relation to the state of the catalyst, the type of oxidant, and the morphology of the polypyrrole powder.

Epidermis Proliferative Effect of the Panax ginseng Ginsenoside $Rb_2$

  • Choi, Seong-Won
    • Archives of Pharmacal Research
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    • v.25 no.1
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    • pp.71-76
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    • 2002
  • Ginseng has been used as a traditional medicine with various therapeutic effects. However, it is still unknown which component of this plant is effective at promoting wound healing. Recently, ginsenoside $Rb_2$ has been reported to improve wound healing. In this study, to investigate the reported wound healing effect of the ginsenoside $Rb_2$, cell morphology and protein factors involved in epidermal formation were evaluated by immunshemical and immunoblotting analysis. $Rb_2$ stimulated epidermal cell proliferation, and the cell showed a 1.5-fold increase in thymidine uptake compared to the control (p<0.05, n=3). Futheremore $Rb_2$, was found to stimulate epidermis formation in a dose-dependent manner in raft culture, and to dose dependently enhance the expressions of protein factors related to cell proliferation, namely, epidermal growth factor and its receptor, fibronectin and its receptor, keratin 5/14, and collagenase 1 (p<0.05, n=3~9). It is believed that ginsenoside $Rb_2$, enhances epidermal cell proliferation by upregulating the expressions of these proliferation-related factors.

Combined Age and Segregated Kinetic Model for Industrial-scale Penicillin Fed-batch Cultivation

  • Wang Zhifeng;Lauwerijssen Maarten J. C.;Yuan Jingqi
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.2
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    • pp.142-148
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    • 2005
  • This paper proposes a cell age model for Penicillium chrysogenum fed-batch cultivation to supply a qualitative insight into morphology-associated dynamics. The average ages of the segregated cell populations, such as growing cells, non-growing cells and intact productive cells, were estimated by this model. A combined model was obtained by incorporating the aver-age ages of the cell sub-populations into a known but modified segregated kinetic model from literature. For simulations, no additional effort was needed for parameter identification since the cell age model has no internal parameters. Validation of the combined model was per-formed by 20 charges of industrial-scale penicillin cultivation. Meanwhile, only two charge-dependent parameters were required in the combined model among approximately 20 parameters in total. The model is thus easily transformed into an adaptive model for a further application in on-line state variables prediction and optimal scheduling.

Establishment and Characterization of Permanent Cell Lines from Oryzias dancena Embryos

  • Lee, Dongwook;Kim, Min Sung;Nam, Yoon Kwon;Kim, Dong Soo;Gong, Seung Pyo
    • Fisheries and Aquatic Sciences
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    • v.16 no.3
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    • pp.177-185
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    • 2013
  • The development of species-specific fish cell lines has become a valuable tool for biological research. In recent years, marine medaka Oryzias dancena has been recognized as a good experimental model fish but there are no reports of establishment of cell lines from this fish. In this study, two cell lines from O. dancena blastula embryos were established from 41 total trials (4.9%). The two cell lines displayed typical in vitro morphology and have been cultured for >121 passages, which corresponds to 293 days. The doubling times of the cell lines were 29.84 and 28.59 h, respectively, and both possessed the potential to expand in a clonal manner, albeit with significant differences between the two cell lines. The absence of any of the four main medium supplements; i.e., fish serum, fetal bovine serum, basic fibroblast growth factor, and medaka embryo extract, significantly inhibited growth. The proportion of cells possessing normal chromosome number was 45% and 46.7% of the cell lines, respectively. Taken together, two cell lines that proliferate continuously were established from marine medaka and these cell lines may provide a basic tool for characterizing the unique features of this fish species.

Cellular viability and genetic expression of human gingival fibroblasts to zirconia with enamel matrix derivative ($Emdogain^{(R)}$)

  • Kwon, Yong-Dae;Choi, Hyun-Jung;Lee, Heesu;Lee, Jung-Woo;Weber, Hans-Peter;Pae, Ahran
    • The Journal of Advanced Prosthodontics
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    • v.6 no.5
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    • pp.406-414
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    • 2014
  • PURPOSE. The objective of this study was to investigate the biologic effects of enamel matrix derivative (EMD) with different concentrations on cell viability and the genetic expression of human gingival fibroblasts (HGF) to zirconia surfaces. MATERIALS AND METHODS. Immortalized human gingival fibroblasts (HGF) were cultured (1) without EMD, (2) with EMD $25{\mu}g/mL$, and (3) with EMD $100{\mu}g/mL$ on zirconia discs. MTT assay was performed to evaluate the cell proliferation activity and SEM was carried out to examine the cellular morphology and attachment. The mRNA expression of collagen type I, osteopontin, fibronectin, and TGF-${\beta}1$ was evaluated with the real-time polymerase chain reaction (RT-PCR). RESULTS. From MTT assay, HGF showed more proliferation in EMD $25{\mu}g/mL$ group than control and EMD $100{\mu}g/mL$ group (P<.05). HGFs showed more flattened cellular morphology on the experimental groups than on the control group after 4h culture and more cellular attachments were observed on EMD $25{\mu}g/mL$ group and EMD $100{\mu}g/mL$ group after 24h culture. After 48h of culture, cellular attachment was similar in all groups. The mRNA expression of type I collagen increased in a concentration dependent manner. The genetic expression of osteopontin, fibronectin, and TGF-${\beta}1$ was increased at EMD $100{\mu}g/mL$. However, the mRNA expression of proteins associated with cellular attachment was decreased at EMD $25{\mu}g/mL$. CONCLUSION. Through this short term culture of HGF on zirconium discs, we conclude that EMD affects the proliferation, attachment, and cell morphology of HGF cells. Also, EMD stimulates production of extracellular matrix collagen, osteopontin, and TGF-${\beta}1$ in high concentration levels. CLINICAL RELEVANCE. With the use of EMD, protective barrier between attached gingiva and transmucosal zirconia abutment may be enhanced leading to final esthetic results with implants.

Effect of Ailanthus altissima Water Extract on Cell Cycle Control Genes in Jurkat T Lymphocytes (Jurkat T 임파구의 세포주기 기전에 미치는 저근백피(Ailanthus altissima)의 효과)

  • 전병훈;황상구;이형철;김춘관;김대근;이기옥;윤용갑
    • YAKHAK HOEJI
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    • v.46 no.1
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    • pp.18-23
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    • 2002
  • Ailanthus altissima has been used to settle an upset stomach, to alleviate a fever and as an insecticide. We reported that the water extract of A. altissima induced apoptotic cell death in Jurkat T-acute Iymphoblastic leukemia cells. Here, we showed the dose-dependent inhibitions of cell viability by the extract, as measured by cell morphology. The cell cycle control genes are considered to play important roles in tumorigenesis. The purpose of the present study is also to investigate the effect of A. altissima on cell cycle progression and its molecular mechanism in the cells. The level of p21 protein was increased after treatment of the extract, whereas both Bcl-2 and Bax protein levels were not changed. These results suggest that A. altissima induces apoptotic cell death via p21-dependent signaling pathway in Jurkat cells which delete wild type p53. Gl checkpoint related gene products tested (cyclin D3, cyclin dependent kinase 4, retinoblastoma, E2Fl) were decreased in their protein levels in a dose-dependent manner after treatment of the extract Taken together, these results indicate that the increase of apoptotic cell death by A. altissima may be due to the inhibition of cell cycle in Jurkat cells.

Effects of Sodium Valproate on the Growth of Human Ovarian Cancer Cell Line HO8910

  • Yan, Hong-Chao;Zhang, Jie
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.12
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    • pp.6429-6433
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    • 2012
  • To explore a possible new treatment for human ovarian cancer, we studied the effects of sodium valproate on the growth of the HO8910 human cell line. HO8910 cells were cultured in vitro and treated with different concentrations of sodium valproate. Cell proliferation, cell cycling, and apoptosis were measured by flow cytometry, cell morphology under a microscope, and expression levels of WWOX and P27 by Western blotting and RT-PCR. Tumor xenografts were established to determine in vivo effects of sodium valproate. Our results showed that cell proliferation was decreased with increasing concentration of sodium valproate, with features of cytoplasmic retraction and floating cells. Moreover, cell cycle analysis revealed a higher apoptosis rate and $G_0/G_1$ phase in the sodium valproate experimental group than in the control group. In addition, protein expression levels of WWOX and P27 were elevated. Importantly, sodium valproate decreased in vivo xenograft tumor burden and up-regulated WWOX and P27 expression in nude mice. In conclusion, sodium valproate might play a role in inhibition and control of ovarian cancer cell line HO8910 by inhibiting cell proliferation, interfering with the cell cycle and promoting apoptosis, so that it may be effective in the clinical treatment of ovarian cancer.

Differences in Their Proliferation and Differentiation between B-1 and B-2 Cell

  • Yeo, Seung-Geun;Cha, Chang-Il;Park, Dong-Choon
    • IMMUNE NETWORK
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    • v.6 no.1
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    • pp.1-5
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    • 2006
  • Background: B cell subset has been divided into B-1 cells and B-2 cells. B-1 cells are found most prominently in the peritoneal cavity, as well as constituting a small pro portion of splenic B cells and they are larger and less dense than B-2 cells in morphology. This study was designed to compare the differences in their proliferation and differentiation between B-1 and B-2 cell. Methods: We obtained sorted B-1 cells from peritoneal fluid and B-2 cells from spleens of mice. Secreted IgM was measured by enzyme-linked immunosorbent assay. Entering of S phase in response to LPS-stimuli was measured by proliferative assay. Cell cycle analysis by propidium iodide was performed. p21 expression was assessed by real time PCR. Results: Cell proliferation and cell cycle progression in B-1 and B-2 cells, which did not occur in the absence of LPS, required LPS stimulation. After LPS stimulation, B-1 and B-2 cells were shifted to Sand G2/M phases. p21 expression by resting B-1 cells was higher than that of resting B-2 cells. Conclusion: B-1 cells differ from conventional B-2 cells in proliferation, differentiation and cell cycle.

Senescence as A Consequence of Ginsenoside Rg1 Response on K562 Human Leukemia Cell Line

  • Liu, Jun;Cai, Shi-Zhong;Zhou, Yue;Zhang, Xian-Ping;Liu, Dian-Feng;Jiang, Rong;Wang, Ya-Ping
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.12
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    • pp.6191-6196
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    • 2012
  • Aims and Background: Traditional chemotherapy strategies for human leukemia commonly use drugs based on cytotoxicity to eradicate cancer cells. One predicament is that substantial damage to normal tissues is likely to occur in the course of standard treatments. Obviously, it is urgent to explore therapies that can effectively eliminate malignant cells without affecting normal cells. Our previous studies indicated that ginsenoside $Rg_1$ ($Rg_1$), a major active pharmacological ingredient of ginseng, could delay normal hematopoietic stem cell senescence. However, whether $Rg_1$ can induce cancer cell senescence is still unclear. Methods: In the current study, human leukemia K562 cells were subjected to $Rg_1$ exposure. The optimal drug concentration and duration with K562 cells was obtained by MTT colorimetric test. Effects of $Rg_1$ on cell cycle were analyzed using flow cytometry and by SA-${\beta}$-Gal staining. Colony-forming ability was measured by colony-assay. Telomere lengths were assessed by Southern blotting and expression of senescence-associated proteins P21, P16 and RB by Western blotting. Ultrastructural morphology changes were observed by transmission electron microscopy. Results: K562 cells demonstrated a maximum proliferation inhibition rate with an $Rg_1$ concentration of $20{\mu}\;mol{\cdot}L^{-1}$ for 48h, the cells exhibiting dramatic morphological alterations including an enlarged and flat cellular morphology, larger mitochondria and increased number of lysosomes. Senescence associated-${\beta}$-galactosidase (SA-${\beta}$-Gal) activity was increased. K562 cells also had decreased ability for colony formation, and shortened telomere length as well as reduction of proliferating potential and arrestin $G_2$/M phase after $Rg_1$ interaction. The senescence associated proteins P21, P16 and RB were significantly up-regulated. Conclusion: Ginsenoside $Rg_1$ can induce a state of senescence in human leukemia K562 cells, which is associated with p21-Rb and p16-Rb pathways.