• Proceedings of the Korean Society of Toxicology Conference
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• 2005.05a
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• pp.110-110
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• 2005

• Biomolecules & Therapeutics
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• v.22 no.4
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• pp.301-307
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• 2014

Fucodiphlorethol G (6'-[2,4-dihydroxy-6-(2,4,6-trihydroxyphenoxy)phenoxy]biphenyl-2,2',4,4',6-pentol) is a compound purified from Ecklonia cava, a brown alga that is widely distributed offshore of Jeju Island. This study investigated the protective effects of fucodiphlorethol G against oxidative damage-mediated apoptosis induced by ultraviolet B (UVB) irradiation. Fucodiphlorethol G attenuated the generation of 2, 2-diphenyl-1-picrylhydrazyl radicals and intracellular reactive oxygen species in response to UVB irradiation. Fucodiphlorethol G suppressed the inhibition of human keratinocyte growth by UVB irradiation. Additionally, the wavelength of light absorbed by fucodiphlorethol G was close to the UVB spectrum. Fucodiphlorethol G reduced UVB radiation-induced 8-isoprostane generation and DNA fragmentation in human keratinocytes. Moreover, fucodiphlorethol G reduced UVB radiation-induced loss of mitochondrial membrane potential, generation of apoptotic cells, and active caspase-9 expression. Taken together, fucodiphlorethol G protected human keratinocytes against UVB radiation-induced cell damage and apoptosis by absorbing UVB radiation and scavenging reactive oxygen species.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.2
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• pp.346-349
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• 2008

To investigate whether aqueous extract from Aconitum koreanum (AEAK) effects in the process of melanin synthesis, the expression of tyrosinase-related proteins (TRPs) by immunohistochemical methods were performed in ultraviolet B (UVB) irradiated skin of guinea pig. The irradiation of UVB (60 mJ/day) was performed for 3 days and treated with AEAK for 15 days. About the color evaluation, the visual scores of UV B irradiated guinea pig with AEAK treatment were slightly lower than those in the UV B alone irradiated ones. At day 15 after UVB exposure, immunohistochemical analysis for TRPs expression were performed. The intensive expression of tyrosinase was mainly observed over epidermis with skin appendage and in the cells of dermis. Slight increase of these reaction was induced in response to UVB in the spinous and granular layer of epidermis, but similar expression in the AEAK treated guinea pig as normal one. The TRP-1 and TRP-2 expression were not detected in the skin of normal guinea pig. But intensive expression for TRP-1 and TRP-2, especially TRP-2, induced by UV B irradiation in the cells of dermis. These expressions were decreased in the AEAK treated guniea pig. Collectively, these results suggest that AEAK has a potential to inhibit synthesis through regulation of TRPs expression in the skin of guinea pig, but better understanding the function of AEAK, more research should be done in the effects of AEAK on the function of TRPs in melanogesis.

• Korean Journal of Veterinary Research
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• v.49 no.1
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• pp.17-22
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• 2009

The effect of Bu-Zhong-Yi-Qi-Tang (BZYQT) on the changes of ultraviolet (UV) light B radiation-induced apoptotic sunburn cell (SBC) and epidermal ATPase-positive dendritic cell (DC) in SKH1- hr or ICR mouse were investigated. The mice were treated with UVB (200 mJ/$cm^2$) and were sacrificed 24 h later. BZYQT (50 mg/kg of body weight) or vehicle (saline) was given i.p. at 36 and 12 h before irradiation, and 30 min after irradiation or BZYQT cream (0.2%) or cream base (vehicle) was topically treated at 24 h and 15 min before irradiation, and immediately after irradiation. The skin of SKH1-hr mouse prepared from the back of untreated mice exhibited about 0.3 SBC/cm length of epidermis, and 24 h after UV irradiation, the applied areas show an increased number of SBCs. But the frequency of UVB-induced SBC formation was reduced by intraperitoneal injection of BZYQT extract (p < 0.01). The numbers of DC in normal ICR mouse were 628.00 ${\pm}$ 51.56 or 663.20 ${\pm}$ 62.58 per $mm^2$ of ear epidermis. By 1 day after UVB treatment, the number of ATPase-positive cells/$mm^2$ were decreased by 39.0% or 27.1% in i.p. or topical application group with vehicle. Treatment of BZYQT was associated with increase of 33.9% in i.p. group (p < 0.05) or 2.7% in topical application group in the number of ATPase positive cells compared with the irradiation control group. The results presented herein that BZYQT administration could reduce the extent of skin damages produced by UVB.

• Journal of Radiation Protection and Research
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• v.32 no.2
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• pp.59-64
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• 2007

We induced the activation of melanocytes in the epidermis of C57BL/6 mice by ultraviolet B (UVB) irradiation and observed the effect of bamboo (Phyllostachys nigra var. henenis Strapf) leaf extract (BLE) on the formation, and decrease of UVB-induced epidermal melanocytes. C57BL/6 mice were irradiated by $UVB\;80mJ/cm^2(0.5mW/sec)$ daily for 7 days, and BLE was intraperitoneally or topically applied pre-or post-irradiation. For the estimation of change of epidermal melanocytes, light microscopic observation with dihydroxyphenylalanine (DOPA) stain was performed. Split epidermal sheets prepared from the ear of untreated mice exhibited 11-16 $melanocytes/mm^2$, and one week after UV irradiation, the applied areas show an increased number of strongly DOPA-positive melanocytes with stout dendrites. But intraperitoneal or topical treatment with BLE before each irradiation interrupted UVB-induced pigmentation and resulted in a marked reduction in the number of epidermal melanocytes as compared to radiation control skin. The number and size of DOPA-positive epidermal melanocytes were also significantly decreased in intraperitoneally injected or topically applicated group after irradiation with BLE at 3rd and 6th weeks after irradiation. The results of present study indicate that BLE is likely to be useful as inhibitor of UVB-induced pigmentation and depigmenting agent.

• Journal of Ginseng Research
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• v.30 no.4
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• pp.194-198
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• 2006

The effects of red ginseng (RG) on the changes of ultraviolet (UV) light B radiation-induced apoptotic sun-burn cell (SBC) and epidermal ATPase-positive dendritic cell (DC) in SKH 1-hr or ICR mouse were investigated. The mice were treated with UVB ($200mJ/cm^2$) and were sacrificed 24 hours later. RG (50 mg/kg of body weight) or vehicle (saline) was given i.p. at 36 and 12 hours before irradiation, and 30 minutes after irradiation. RG cream (0.2%) or cream base (vehicle) was also topically treated at 24 hours and 15 minutes before irradiation, and immediately after irradiation. The skin of SKH 1-hr mouse prepared from the back of untreated mice exhibited about 0.3 SBC/cm length of epidermis, and 24 hours after UV irradiation, the applied areas show an increased number of SBCs. But the frequency of UVB-induced SBC formation was significantly reduced by intraperitoneal injection of RG extract. The numbers of DC in normal ICR mouse were $628.00{\pm}51.56\;or\;663.20{\pm}62.58\;per\;mm^2$ of ear epidermis. By 1 day after UVB treatment, the number of ATPase-positive $cells/mm^2$ were decreased by 39.0% or 27.1% in i.p. or topical application group with vehicle. The frequency of UVB ($200mJ/cm^2$)-induced DC decrease was reduced by treatment of RG as 31.3% in i.p. group and 22.4% in topical application group compared with the irradiation control group. The results presented herein that RG administration could reduce the extent of skill damages produced by UVB.

• Journal of Photoscience
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• v.9 no.2
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• pp.217-220
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• 2002

Ultraviolet B (UVB) radiation may activate or deteriorate cultured human epidermal melanocytes, depending on the doses and culture conditions. In this study, we examined whether apoptosis of melanocytes can be induced by physiologic doses of UVB irradiation. PI staining for DNA condensation and flow cytometric analyses demonstrated the apoptotic cell death of melanocytes after UVB irradiation. The level of p53 and Bax revealed a dose-dependent increase with increasing dose of UVB, but the level of Bcl-2 remained unchanged. Confocal microscopic examination showed that Bax moved trom a diffuse to a punctate distribution after UVB irradiation. However, there were no changes in the pattern of Bcl-2. We next examined the downstream targets of apoptosis. Our results showed that a precursor form of caspase-3 disappeared with increasing doses of UVB. We also observed cleavage of poly(ADP-ribose) polymerase (PARP) after UVB irradiation. In addition, UVB irradiation resulted in a remarkable activation of c-Jun N-terminal kinase (JNK). These results indicate that UVB may induce apoptosis via JNK activation in human melanocytes.

• Journal of Environmental Science International
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• v.7 no.4
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• pp.487-492
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• 1998

The experiment was conducted to determine the effects of enhanced UV-B on growth and differential responses among cultivars in soybean. The soybean cultivars subjected to enhanced UV-B irradiation at daily dose of 11.32 kJ $m^{-2}(UV-B_{BE})$ revealed that the growth was significantly depressed. Plant height, leaf number, leaf area and dry weight were inhibited by UV-B irradiation showing differential responses among cultivars used. Danyeubkong seems to be less sensitive to the enhanced W-B irradiation, while Keunolkong more sensitive. Reduction of chlorophyll content was also found significantly greater to Keunolkong. Specific leaf weight an index of leaf thickness, and flavonoid content known as UV-absorbing compounds were significantly Increased in Danyeubkong by UV-B, but those In the other cultivars were not significantly affected. The results indicated that there are cultivar diferences in tile growth and phisiological responses to the enhanced UV-B irradiation and specific leaf weight and UV-absorbing compounds in the leaves were highly related to the sensitivity of soybean by UV-B irradiation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.10
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• pp.878-884
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• 1998

We have investigated that the monodomain alignment of nematic liquid crystal (NLC) is obtained with polarized ultraviolet(PUV) light irradiation on polyimide (PI) surface. The LC alignment capability increases with increasing the UV light irradiation time. The polarized UV light irradiation on oblique angle of 60。 irradiated on PI surface rotated by 90。 at 10 min. after being normally irradiated on PI surface at 30 min., the generated pretilt angle of NLC is about 2.5。. The pretilt angle of NLC is attributed to the interaction between the LC molecules and the asymmetric triangular structure of polymer surface due to photo-depolymerization of polymer with the oblique UV light on PI surface. The voltage -transmittance and response time characteristics of photo-aligned twisted nematic (TN)-LCD with UV light irradiation time 60 min. were almost same in comparison with the rubbing-treated TN-LCD.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.109-112
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• 1998

In this paper, we studied on electro-optical (EO) characteristics of photo-aligned twisted nematic (TN)-LCD. We obtained that uniform LC alignment in TN-LCD with linearly polarized ultraviolet (LPUV) light irradiation on polyimide (PI) surface increases according to increasing irradiation time for 10 to 60 min. The voltage-transmittance and response time characteristics of photo-aligned TN-LCD with UV light irradiation time of 60 min were almost same in comparison with conventional TN-LCD were observed. From the results, we suggest that photo-aligned TN-LCD with LPUV light irradiation on PI surface is useful in applying LCD as for rubbing-free treatment method.