• Journal of Microbiology and Biotechnology
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• v.11 no.5
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• pp.749-755
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• 2001

High Electromagnetic Field (EMF) with an intensity of 1 mT (Tesla) inhibited the growth of both human normal lung and immune T cell down to $20-30\%$, compared to that of an unexposed case. The human T-cells, Jurkat, were more severely affected by EMF than the human lung cells, which showed a relatively slow cell growth and substantial releas of $Ca^+2$ (3.5 times higher than the human T-cells). However, the growth of hepatoma carcinoma, Hep3B, was enhanced by twice that of an unexposed case. The EMF intensity and exposure time did not affect the growth of the cancer cells very much, while it significantly affected the growth of normal cells. Accordingly, it is possible that EMFs may play a role in the initiation of cancer. The EMFs disturbed the signal transduction and membrane systems, such that a five times higher amount of PKC-${\alpha}$ was released from the cell membrane than in the control. Extended exposure to EMFs, for more than 48 hours, also led to 1 $90\%$ necrotic death pattern from apoptotic cell death. Finally, EMF at an intensity of 1mT with a 24-T exposure promoted the differentiation of HL-60 cells to monocytes/macrophages, possibly causing potential acute leukemia.

• Proceedings of the Microbiological Society of Korea Conference
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• 2008.05a
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• pp.62-64
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• 2008

A major hurdle to the development of RNA interference as therapy for HIV infection is the delivery of siRNA to T lymphocytes which are difficult cells to transfect even in vitro. We have employed a single chain antibody to the pan T cell surface antigen CD7 was conjugated to an oligo-9-arginine peptide (scFvCD7-9R) for T cell-specific siRNA delivery in NOD/SCIDIL2${\gamma}$-/- mice reconstituted with human peripheral blood lymphocytes (Hu-PBL). Using a novel delivery, we first show that scFvCD7-9R efficiently delivered CD4 siRNA into human T cells in vitro. In vivo administration to Hu-PBL mice resulted in reduced levels of surface CD4 expression on T cells. Mice infected with HIV-1 and treated on a weekly basis with scFvCD7-9R-siRNA complexes targeting a combination of viral genes and the host coreceptor molecule CCR5 successfully maintained CD4/CD3 T cell ratios up to 4 weeks after infection in contrast to control mice that displayed a marked reduction in CD4 T cell numbers. p24 antigen levels were undetectable in 3 of the 4 protected mice. scFvCD7-9R/antiviral siRNA treatment also helped maintain CD4 T cell numbers with reduced plasma viral loads in Hu-PBL mice reconstituted with PBMC from donors seropositive for HIV, indicating that this method can contain viral replication even in established HIV infections. Our results show that scFvCD7-9R could be further developed as a potential therapeutic for HIV-1 infection.

• Biomolecules & Therapeutics
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• v.24 no.3
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• pp.244-251
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• 2016

Understanding the developmental mechanisms of humoral immunity against intranasal antigens is essential for the development of therapeutic approaches against air-borne pathogens as well as allergen-induced pulmonary inflammation. Follicular helper T (Tfh) cells expressing CXCR5 are required for humoral immunity by providing IL-21 and ICOS costimulation to activated B cells. However, the regulation of Tfh cell responses against intranasal antigens remains unclear. Here, we found that the generation of Tfh cells and germinal center B cells in the bronchial lymph node against intranasal proteinase antigens was independent of $TGF-{\beta}$. In contrast, administration of STAT3 inhibitor STA-21 suppressed the generation of Tfh cells and germinal center B cells. Compared with wild-type OT-II T cells, STAT3-deficient OT-II T cells transferred into recipients lacking T cells not only showed significantly reduced frequency Tfh cells, but also induced diminished IgG as well as IgE specific for the intranasal antigens. Cotransfer study of wild-type OT-II and STAT3-deficient OT-II T cells revealed that the latter failed to differentiate into Tfh cells. These findings demonstrate that T cell-intrinsic STAT3 is required for the generation of Tfh cells to intranasal antigens and that targeting STAT3 might be an effective approach to ameliorate antibody-mediated pathology in the lung.

• 대한두경부종양학회:학술대회논문집
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• 1991.11a
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• pp.22.2-24
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• 1991

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.631-637
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• 2013

Luteolin is a naturally occurring flavonoid present in many plants with diverse applications in pharmacology. Despite several studies elucidating its significant anti-cancer activity against various cancer cells, the mechanism of action in skin cancer is not well addressed. Hence, we investigated the effects of luteolin in HaCaT (human immortalized keratinocytes) and A375 (human melanoma) cells. The radical scavenging abilities of luteolin were determined spectrophotometrically, prior to a cytotoxic study (XTT assay). Inhibitory effects were assessed by colony formation assay. Further, the capability of luteolin to induce cell cycle arrest and apoptosis were demonstrated by flow cytometry and cellular DNA fragmentation ELISA, respectively. The results revealed that luteolin possesses considerable cytotoxicity against both HaCaT and A375 cells with $IC_{50}$ values of 37.1 ${\mu}M$ and 115.1 ${\mu}M$, respectively. Luteolin also inhibited colony formation and induced apoptosis in a dose and time-dependent manner by disturbing cellular integrity as evident from morphological evaluation by Wright-Giemsa staining. Accumulation of cells in G2/M (0.83-8.14%) phase for HaCaT cells and G0/G1 (60.4-72.6%) phase for A375 cells after 24 h treatment indicated cell cycle arresting potential of this flavonoid. These data suggest that luteolin inhibits cell proliferation and promotes cell cycle arrest and apoptosis in skin cancer cells with possible involvement of programmed cell death, providing a substantial basis for it to be developed into a potent chemopreventive template for skin cancer.

• Biomedical Science Letters
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• v.20 no.3
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• pp.162-167
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• 2014

Tuberculosis (TB) is one of the major global health problems and it has been estimated that in 5~10% of Mycobacterium tuberculosis (MTB)-infected individuals, the infection progresses to an active disease. Numerous cytokines and chemokines regulate immunological responses at cellular level including stimulation and recruitment of wide range of cells in immunity and inflammation. In the present study, the mRNA expression levels of eight host immune markers containing of IFN-${\gamma}$, TNF-${\alpha}$, IL-2R, IL-4, IL-10, CXCL9, CXCL10, and CXCL11 in whole blood cells from active pulmonary TB patients were measured after T-cell mitogen (PHA) and MTB specific antigens (ESAT-6, CFP-10, and TB7.7). Among the TH1-type factors, IFN-${\gamma}$ mRNA expression was peaked at 4 h, TNF-${\alpha}$ and IL-2R mRNA expression was significantly high at the late time points (24 h) in active TB patients, TH2-type cytokine (IL4 and IL10) mRNA expression levels in both active TB and healthy controls samples did not changed significantly, and the mRNA expression of the three IFN-${\gamma}$-induced chemokines (CXCL9, CXCL10, and CXCL11) were peaked at the late time points (24 h) in active TB patients after MTB specific antigen stimulation. In conclusion, the mRNA expression patterns of the TB-related immune markers in response to the T-cell mitogen (PHA) differed from those in response to MTB specific antigens and these findings may helpful for understanding the relationship between MTB infection and host immune markers in a transcripts level.

• Natural Product Sciences
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• v.2 no.2
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• pp.123-129
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• 1996

Chemical carcinogenesis is associated with the increase of intracellular polyamine levels, and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse epidermal ODC activity are essential to skin tumor promotion by TPA. Therefore, for the discovery of new cancer chemopreventive agents, we have evaluated about 73 kinds of natural products to study inhibitory effects against ODC activity induced by TPA in T24 cell culture system. The total methanol extracts of plants fractionated into three layers (hexane, ethyl acetate and water layer) were tested and the hexane fraction of Angelica gigas $(root\;bark,\;IC_{50}:\;7.4\;{\mu}g/ml)$ and the ethyl acetate fraction of Corydalis ternata $(root,\;IC_{50}:\;7.5\;{\mu}g/ml)$ were the most effective on the inhibition of TPA-induced ODC activity, These active fractions are under investigation with further sequential fractionation using column chromatography.

• Fisheries and Aquatic Sciences
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• v.27 no.10
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• pp.677-686
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• 2024

Unstable changes in environmental temperature (during the dry season there are several times of rain) can damage the fish reproductive cycle, leading to inhibition of spawning activity. Low temperatures cause slow fish gonad maturation, while high temperatures cause delays in the spermatogenesis process of male fish. The ideal temperature range can increase fish testosterone (T) levels needed to maintain spermatogenesis and GH expression levels during sperm cell proliferation. The effect of temperature on the presence of exogenous GH (CgGH) in G5 transgenic mutiara catfish formed through broodstock breeding GH-transgenesis technology in previous research needs to be evaluated for testicular fertility, especially T levels and spermatozoa (Spz) density during fish gonad maturation. The results showed that the ideal temperature that increases T levels, Spz density and CgGH expression levels in G5 transgenic mutiara catfish is 24℃. Temperatures of 28℃ and 32℃ tended to reduce T levels and Spz density in both transgenic and nontransgenic catfish. Besides that, the sperm maturation stage (formation of Spz) was more dominantly induced by 24℃ compared to other temperature treatments. This indication shows that the maximum enzyme activity involved in T production to drive the spermatogenesis process is regulated at 24℃. As a consequence, the use of transgenic male fish broodstock (transgenesis-GH) and temperature regulation for male fish gonad maturation is more profitable in the range of 24℃-28℃.

• Journal of Life Science
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• v.29 no.7
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• pp.779-784
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• 2019

Free radicals are known to inhibit hair vitality by damaging the cell membranes of the hair follicles. The purpose of this study was to determine the antioxidant activities and the capacity for hair loss prevention of extracts from Platycodon grandiflorum. We prepared butanol (BF) and water (WF) fractions from P. grandiflorum. DPPH and ABTS radical scavenging activities were measured to investigate the antioxidant activities of the fractions. Both fractions exhibited dose-dependent antioxidant activities for DPPH radical production, and BF and WF almost completely suppressed ABTS radical production when supplied at 10 and 100 mg/ml, respectively. We confirmed a skin regeneration effect by treating human HaCaT skin cells with a range of BF and WF concentrations for 24 and 48 hr. The extract treatments accelerated cell proliferation. We also assayed the capacity of BF and WF to suppress inflammation using RAW264.7 cells. BF dose-dependently suppressed nitrous oxide (NO) production. Treatment of human hair follicle dermal papilla cells (HFDPC) with BF and WF promoted cell proliferation after 24, 48, and 72 hr of treatment when supplied at 10, 50, 100, and $200{\mu}g/ml$. Taken together, these results confirm the possibility of using BF and WF extracts from P. grandiflorum in formulating hair loss prevention products.

• Korean Journal of Pharmacognosy
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• v.24 no.2
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• pp.159-165
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• 1993

The studies were conducted to investigate the effect of Sinhyo-Taklee-San(STS), which is composed of Astragali Radix(AR), Lonicerae Flos(LF), Angelicae gigantis Radix(AGR) and Glycyrrhizae Radix(GR), on the proliferation of fibroblast cell(Balb/c 3T3). STS, GR and glycyrrhizin increased the proliferation of 3T3 cells. The 10% serum obtained from STS, AR, LF, AGR and GR treated mice also increased the proliferation of 3T3 cells markedly. GR, glycyrrhizin and glycyrrhetinic acid inhibited protein synthesis, but did not affect on DNA synthesis.