• Environmental Mutagens and Carcinogens
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• v.24 no.2
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• pp.91-98
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• 2004

Although 2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD) is a powerful carcinogen in several species, limited model system exist to study carcinogenicity of this compound at cellular level. To enhance our under-standing of carcinogenicity of TCDD at cellular level, we investigated micronucleus (MN) frequency as a index of genetic toxicity and whether TCDD can transform the human cells in culture. Normal human cell lines, skin keratinocyte HaCaT, Chang liver and breast MCF10A cells were used. TCDD did not affect the cell viability of the Chang liver, HaCaT and MCF10A cells. The frequency of micronucleus was increased after treatment of TCDD for 24hr in Chang liver and HaCaT cells, but not changed in MCF10A cells. And we observed putative transformed cells in Chang liver cells exposed to 1 $\mu$M TCDD for 2 weeks. The putative transformed cells were also observed in HaCaT cells with subsequent exposure to TCDD (0.1, 1, 10, 100 nM) for 2 weeks after initial exposure to MNNG, but not observed in MCF10A cells. Collectively, these results indicate that the ability of TCDD to induce micronuclei may be involved in cellular transformation of Chang liver and HaCaT cells. Our putative TCDD-transformed cells of Chang liver and HaCaT are expected to provide a clue to the elucidation of TCDD-induced transformation pathway.

• Journal of Life Science
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• v.24 no.12
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• pp.1301-1307
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• 2014

Adipose-derived stem cells (ADSCs) are considered promising tools for tissue regeneration. However, ADSCs have very poor proliferation capacity. Therefore, fetal bovine serum (FBS) is generally added to the culture media of ADSCs. As FBS contains many uncharacterized components that may affect cellular functions, methods for serum-free cultures of ADSCs have been widely investigated. In this study, to develop an efficient method for a serum-free culture of ADSC-T, we used an ADSC line established by introducing the simian virus 40 (SV40) T gene into primary ADSCs. We then investigated the effect of amino acids, vitamins, and other components on the growth of ADSC-T. When the ADSC-T cells were plated with DMEM/F12 serum-free medium, the cells did not proliferate, and the mixture of amino acids, vitamins, and B27 supplement did not increase the growth of the cells. However, when the ADSC-T cells were provided with serum-free DMEM/F12 after they had been cultured with serum-supplemented DMEM for 24 h, the cells proliferated, and the vitamins and B27 supplement increased the cell growth. Stem-Pro serum-free medium also appeared to be useful as a suspension culture for the ADSC-T cells. The ADSC-T cells secreted large amounts of proteins of around 70 kDa. Insulin-like growth factor (IGF) and fibroblast growth factor basic (FGF basic) were secreted by ADSC-T in larger amounts in the serum-free culture than in the serum-supplemented culture.

• Journal of Sasang Constitution and Immune Medicine
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• v.24 no.4
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• pp.100-108
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• 2012

Objectives : The aim of this study was to report the improvement of fever, myalgia, performance status, and headache after treatment with Osuyubujaijung-tang and Geopoong-san in a Soeumin with Peripheral T-cell lymphoma. Methods : We retrospectively reviewed the medical records, medical laboratory and image scans of 80-year-old male patient diagnosed as peripheral T-cell lymphoma. He couldn't conduct any conventional chemotherapy due to poor performance status, ECOG 4. Results : The symptoms of myalgia, poor performance status, and neck pain improved, and fever was reduced with Osuyubujaijung-tang. Headache was subsided with Geopoong-san. Conclusions : A patient with peripheral T-cell lymphoma suffering from fever, myalgia, poor performance status, neck pain and headache showed the improvement of symptoms with treatment of Osuyubujaijung-tang and Geopoong-san. After 4 months treatment, the patient could conduct self care, physical activity and social affairs.

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.311-317
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• 1999

Human T-cell leukemia virus Type-I (HTLV-I) is etiologically associated with rare adult T-cell leukemia, a malignant T-cell disorder. cDNAs encoding p24 (gag), gp21(env), and pXII of HTLV-I were amplified by polymerase chain reaction (PCR) using the genomic DNA extracted from HUT102 cell line as a template. The amplified cDNAs were cloned into the Escherichia coli expression vectors and over-expression of the recombinant proteins were achieved by adding IPTG into the culture media in order to induce the promoter. The molecular weights of the recombinant p24, gp21, and pXII, determined by SDS-PAGE, were found to be approximately 28 kDa, 23 kDa, and 15 kDa, respectively. Reactivity of the recombinant proteins with human sera was tested by the immunoblot assay. The gp21 and p24 reacted against the sera obtained from HTLV-I-infected individuals but not against the sera obtained from normal persons. These results suggest that the recombinant proteins expressed in E. coli were recognized by antibodies in sera from HTLV-I infected patients. These recombinant proteins would be applicable for detecting the presence of antibodies against HTLV-I in human blood samples.

• Journal of Aquaculture
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• v.11 no.2
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• pp.231-240
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• 1998

Tetraselmis is widely used as a live food because of its easy handling, high nutrient, large size and wide tolerant range of temperature and salinity. In order to find the optimum Tetraselmis species for mass culture in Korea, five species of this microalgae were examined on size, optimum culture condition ${\textperthousand}$s, $^{\circ}C.$) and nutrient composition. The results obtained were as follows: Among five species of Tetraselmis, T. sp.(Haeundae) was the largest(major axis $17.6{\pm}1.87^{\mu}$m, mean cell volume 727${\mu}$m), and T. sp. (China) the smallest (major axis $14.6{\pm}1.46^{\mu}$m, mean cell volume 625m). Tetraselmis was very eurythermal and euryhaline species. But optimum temperature and salinity for growth were 24~$30^{\circ}C.$ and 27~30${\textperthousand}$, respectively. Among five species of Tetraselmis, T. sp. (China) seemed to be the most tolerant of high temperature over $30^{\circ}C.$, and T. tetrathele of low temperature below $6^{\circ}C.$. In culture density, T. suecica showed the highest growth rate among the among the five species. The cell density of this microalgae attained to $141{\times}10^4$cells/ml at $24^{\circ}C.$ and 30${\textperthousand}$ within 7 days. In chemical composition, crude protein amount was the highest in T. suecica (44.50%), and crude lipid amount it T. sp. (Haeundae, 7.13%). Total essential amino acid amount was the highest in T. sp. (Haeundae, 50.4%) and total polyunsaturated amount in T. sp. (China, 11.7%) The results on growth and chemical composition of five species of Tetraselmis indicated that T. suecica seemed to be the most suitable species for mass culture in Korea.

• Molecules and Cells
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• v.40 no.1
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• pp.24-36
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• 2017

The stability of peptide-MHC complex (pMHC) is an important factor to shape the fate of peptide-specific T cell immune response, but how it influences on T cell activation process is poorly understood. To better understand that, we investigated various T cell activation events driven by $L^d$ MHCI loaded with graded concentrations of P2Ca and QL9 peptides, respectively, with 2C TCR Tg T cells; the binding strength of P2Ca for $L^d$ is measurably weaker than that of QL9, but either peptides in the context of $L^d$ interact with 2C TCR with a similar strength. When their concentrations required for early T cell activation events, which occur within several minutes to an hour, were concerned, $EC_{50}s$ of QL9 were about 100 folds lower than those of P2Ca, which was expected from their association constants for $L^d$. When $EC_{50}s$ for late activation events, which takes over several hours to occur, were concerned, the differences grew even larger (> 300 folds), suggesting that, due to weak binding, $L^d/P2Ca$ dissociate from each other more easily to lose its antigenicity in a short time. Accordingly, fixation of $L^d/P2Ca$ with paraformaldehyde resulted in a significant improvement in its immunogenicity. These results imply that binding strength of a peptide for a MHC is a critical factor to determine the duration of pMHC-mediated T cell activation and thus the attainment of productive T cell activation. It is also suggested that paraformaldehyde fixation should be an effective tool to ameliorate the immunogenicity of pMHC with a poor stability.

• Toxicological Research
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• v.13 no.1_2
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• pp.71-78
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• 1997

The mutational effects of pentachlorophenol (PCP) on the hypoxanthine phosphoribosyl transf erase (hprt) locus in human T-cell were analysed by T-cell clonal assay in vitro. Cells were exposed for 24 hours at primary culture to 0~100 ppm (W/V) PCP in dimethyl sulfoxide. Treated cells were allowed at the same time to stimulate by phytohemagglutinin (PHA) and T-cell growth factor (TCGF) and then seeded in medium containing 6-thioguanine to select for hprt-negative routants. We have also defined the optimal condition for the determination of mutant frequency. The parameters investigated include survival counting, first and second subculture for clonal efficiency plating and mutant plating. Under the optimal conditions, mutant frequencies of high dose-treated cells were significantly higher than those of non-treated or low dose cells. The results indicated a clear dose-effect relationship and showed that mutant frequency in 50 ppm PCP treated cell was 4.31$\times$$10^{-5}$ (background, 8.32$\times$$10^{-6}$). Above data strongly suggest that hprt mutation assay can be used as a biomarker for the environmental risk assessment.

• Journal of Magnetics
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• v.20 no.3
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• pp.290-294
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• 2015

To investigate the effects of alternating magnetic field intensity and stimulation time on the proliferation of human breast cancer cells (BT-20), we cultured the cells under a magnetic field with a saw tooth waveform of 2 kHz. The field intensities varied from 3 to 7 mT, and the stimulation time varied from 24 to 72 hours. Cell proliferation decreased dramatically to 40% during magnetic stimulation for 72 hours at 5 mT. However, the cells were not affected by a strong magnetic field of 7 mT. The p-values obtained using statistical package for social science software were below 0.05 for 5-7 mT. This means that the results have statistical significance. However, it is difficult to explain our results based on the physiology of cell membranes, which have various ionic flows at ion channels.

• Environmental Mutagens and Carcinogens
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• v.24 no.1
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• pp.1-9
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• 2004

Three D-type cyelins (D1, D2, and D3) are expressed in G1 phase of the cell cyele and have been implicated in cell transformation and neoplasia in human and mouse. Cyclin D1 overexpression or amplification was described in various human cancers. However, there is controversy about the role of cyclin D2 in cell cyele progression and human carcinogenesis. Specially, loss of cyelin D2 is involved in a vital tumor suppressor function in normal breast tissue, and that its loss may be related to tumorigenesis. The author examined to effect over-expression of cyclin D2 on the cell proliferation, apoptosis, and cell cycle using cyclin D2 transfected stable T47D breast cancer cells to investigate whether cyclinD2 functions as a positive regulator or negative regulator in cell proliferation. Overexpression of cyclin D2 led to the suppression of cell growth in cyclin D2 transfected T47D in both in its expression level and a time dependent manner with up to 50% reduction of cell growth at 72 hours. Therefore, the authors performed the cell cycle phase analysis using the flow cytometry to investigate the effect of cyclin D2 on the cell cycle phase in cyclin D2 transfected stable T47D cells. The flow cytometry analysis revealed increased sub G0 phase in cyclin D2 transfeted cells up to 23% at 72 hours. To confirm these results induced by overexpression of cyclinD2, the apoptotic bodies were counted in control and cyclin D2 transfected T47 cells. There are markedly increases of apoptotic bodies in cyclin D2-transfected cells up to 18%. These results suggested that Cyclin D2 suppresses the cell proliferation in breast cancers cells via the induction of apotosis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.5
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• pp.1449-1455
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• 2004

Bufonis venenum (dried toad venom; Chinese name, Chan su) is a traditional Chinese medicine obtained from the skin venom gland of the toad. It has long been used in treating arrhythmia and other heart diseases in China and other Asian countries. Additionally, Bufonis venenum has been reported to selectively inhibit the growth of various lines of human cancer cells. In the present study, it was examined the effects of extract of Bufonis venenum (EBV) on the growth of human bladder carcinoma cell line T24 in order to investigate the anti-proliferative mechanism and induction of apoptosis by EBV. Treatment of T24 cells to EBV resulted in the growth inhibition, morphological change and induction of apoptotic cell death in a dose-dependent manner. Flow cytometric analysis revealed that EBV treatment caused G2/M phase arrest of the cell cycle and down-regulation of cyclin A, cyclin B1 and Cdc2, which was associated with a marked up-regulation of cyclin-dependent kinases (Cdks) inhibitor p21 (WAF1/CIP1) in a p53-independent manner. The Cdc25C expression was also significantly inhibited by EBV treatment, however Wee1 kinase expression was not affected. The induction of apoptotic cell death by EBV was connected with down-regulation of anti-apoptotic Bcl-XS/L expression without alteration pro-apoptotic Bax expression. Taken together, these findings suggest that EBV may be a potential chemotherapeutic agent for the control of human bladder carcinorma cells and further studies will be needed to identify the active compounds that confer the anti-cancer activity of EBV.