• Korean Journal of Environmental Biology
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• v.19 no.3
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• pp.218-222
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• 2001

Three weeks old Commelina was cultivated in Hoagland solution with or without $(\pm{100\mu{M}\;Cd^{2+}$ and with $100\mu{M}\;Cd^{2+}+100\mu{M\; SA)$ for 4 days. The contents of $Cd^{2+}$ and nonprotein-SH synthesis in roots and isolated epidermal strips were measured. In the treatment of $Cd^{2+}$, the concentration of $Cd^{2+}$ was $98\mu{M}\;Cd^{2+}$/g.fr.wt and it was 6 times higher than that of control. $Cd^{2+}$+SA increased 1.2 times higher concentration of $Cd^{2+}$ than that of the treatment ofTEX>$Cd^{2+}$ alone. In the treatment of TEX>$Cd^{2+}$, nonprotein-SH also increased 2 times higher than that of the control. TEX>$Cd^{2+}$ + SA increased 2 times higher concentration of nonprotein-SH than that of the treatment of TEX>$Cd^{2+}$ as well. In case of isolated epidermal strips, the response was similar with the roots. Therefore, it suggest that the effect of salicylic acid on the accumulation of TEX>$Cd^{2+}$ and nonprotein-SH synthesis in roots, and isolated epidermal strips was related with an increase of the membrane permeability by SA and that SA may be positively involved in the process of nonprotein- SH synthesis.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.2
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• pp.124-139
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• 2000

This study was performed to investigate monoacetylbenzidine(MABZ) and benzidine(BZ) hemoglobin adducts among workers who worked at benzidine based dye manufacturing company, and exposed by benzidine and benzidine based dye. The hemoglobin adducts were compared with work environment assessment result for evaluating the usefulness of biological monitoring. The mean BZ hemoglobin adducts among the first synthesis worker's hemoglobin adducts were $40.69{\mu}gBZ/g$ Hb and those of dry and packing workers were $22.14{\mu}gBZ/g$ Hb. The mean of MABZ hemoglobin adducts among 1st synthesis workers were $255.84{\mu}gMABZ/g$ Hb, dispersion worker's hemoglobin adducts were $76.17{\mu}gMABZ/g$ Hb and synthesis worker's hemoglogin adducts were $28.66{\mu}gMABZ/g$ Hb. Work environment assessment results during past 3 years were $0.0065mg/m^3$ and $0.5659mg/m^3$ of benzidine based dye concentration in ambient air of drying and packing only. Dye producing process was categorized by the possibility of exposure to benzidine and benzidine based dye. BZ and MABZ hemoglobin adducts were $19.55{\mu}gBZ/g$ Hb, $119.80{\mu}gMABZ/g$ Hb among workers who exposed by benzidine dihydrochloride and $16.32{\mu}gBZ/g$ Hb, $316.56{\mu}gMABZ/g$ Hb among workers who exposed by benzidine based dye. BZ hemoglobin adducts were not detected among control group and MABZ hemoglobin adducts were $5.33{\mu}gMABZ/g$ Hb. The differences between control and other exposed group was statistically significant. But there was no statistically significant differences between benzidine dihydrochloride exposed process and benzidine based dye exposed group. BZ and MABZ hemoglobin adducts were $2.23{\mu}gBZ/g$ Hb, $76.17{\mu}gMABZ/g$ Hb and $3.46{\mu}gBZ/g$ Hb, $21.33{\mu}gMABZ/g$ Hb. So hemoglobin adducts of MABZ were 5 ~ 30 time higher than those of BZ(P<0.003). Above results indicate that work environment assessment didn't detected benzidine and benzidine based dye in ambient air but biological monitoring detected those of hemoglobin adducts. Two group's hemoglobin adducts exposed benzidine dihydrochloride and benzidine based dye were high level but wasn't statistically significant and those were not detected in control group.

• Korean Journal of Environmental Agriculture
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• v.20 no.5
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• pp.310-316
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• 2001

To find out the effect of low temperature on the regulation of tomato chloroplast genes, the optimization of the system in chloroplast protein synthesis and the identification of the changes in chloroplast protein synthesis induced by chilling were studied. Incorporation reaction occurred rapidly at the first 30 minutes and was constantly maintained after 60 minutes. A broad optimal temperature on protein synthesis was found around 20 to $30^{\circ}C$. No difference was shown in the chloroplast protein synthesis under high light intensity (1600 ${\mu}E/m^2/s$) as well as under low light intensity (400 ${\mu}E/m^2/s$) even darkness. $K^+$, $Mg^{++}$ and ATP at an optimal concentration act as an activator, while DTT, chloramphenicol, cycloheximide, $Ca^{++}$ and inorganic phosphate act as an inhibitor in the chloroplast protein synthesis. Synthesis of 15, 55 and 60 kd chloroplast encoded stromal proteins and 18, 24, 33 and 55 kd chloroplast encoded thylakoid membrane proteins were reduced by chilling, while 17 kd chloroplast encoded stromal protein and 16 kd chloroplast encoded thylakoid membrane protein was induced by chilling. It was expected that the 55 kd stromal protein would be the large subunit of rubisco and the 33 kd thylakoid membrane protein would be the D1 protein which was drastically reduced by chilling.

• Journal of environmental and Sanitary engineering
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• v.14 no.1
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• pp.62-69
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• 1999

In this study, the synthesis of PZT powder by bubble column reactor was investigated at various reaction conditions. As a result, the volume % of $NH_3$ gas used as a precipitator had no effect on the synthesis, but the more research is needed to control particle size.As a carrier gas, Ar, $O_2$ and air only increased the stirring effect but had no effect chemically on the synthesis. The calcination temperature of prepared PZT powder was about $500-600^{\circ}C$ and the meanparticle size of synthesized PZT powder was about $0.17{\mu}m$. The grain size of sintered body is about $0.5~3{\mu}m$ and this is similar with the value of commercial products.

• Journal of the Korean Applied Science and Technology
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• v.27 no.1
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• pp.20-28
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• 2010

Melanoma is the most aggressive form of skin cancer and is the fastest growing type of cancer in the United States. We report here the synthesis of a novel series of quinazolinylmethoxybenzene derivatives 1a-c and their antiproliferative activities against A375 human melanoma cell line. Among them, urea compound 1a ($IC_{50}\;=\;4.8\;{\mu}M$) having 4-chloro-3-trifluoromethylphenyl moiety showed superior antiproliferative activity to Sorafenib ($IC_{50}\;=\;5.5\;{\mu}M$) as a reference compound. These results will helpful for designing structure of a therapeutic agent for the treatment of melanoma.

• Korean Journal of Microbiology
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• v.29 no.1
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• pp.25-33
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• 1991

Antiviral activities of papaverine and nucleoside analogs, 9-[(1,3-dihydroxy-2-propoxy)methyl]guanine (DHPG) and acyclovir, against human cytomegalovirus (HCMV) infection were compared in vitro. Papaverine and DHPG were effective in reducing infectious HCMV yields with $ED_{50}{\s}$ (effective dose 50: the concentraion at which 50% of virus yields was obtained) of approximately 1.02 and $0.45{\mu}{\M}$, respectively; while acyclovir was less effective with an $ED_{50}$ of about $10.4{\mu}{\M}$The relative cytotoxicity of these drugs was evaluated under the same conditions used to measure infectious HCMV yields. Papaverine and DHPG demonstrated little cellular toxicity as measured by their effect on the viability of confluent cells at concentrations in the range of those demonstrating potent inhibition of HCMV replication. Similarly, protein synthesis was largely unaffected by these drugs in stationary mock-infected cells as measured by the incorporation of isotopically labelled amino acids. In contrast, cellular DNA synthesis was invariably reduced in the presence of either drug. HCMV-specific DNA synthesis was also strongly inhibited by papaverine and DHPG.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.3
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• pp.41-49
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• 1999

In this paper, we design a controller using the $\mu$-synthesis method and apply it for the spring-mass system with noncollocated sensors and actuators. We assume that the values of the spring stiffness and load mass of the plant are uncertain. The plant is modeled with parametric uncertainty by using the state space equation, especially the descriptor form. The $H_\infty$ controller designed by the $\mu$-synthesis method is compared with the standard $H_\infty$ controller To compare performances of two $H_\infty$ controllers, it is assumed that both controllers were designed with same weighting functions except that the $\mu$-synthesis controller has structured uncertainties. By compared with the standard $H_\infty$ controller, we show that the designed controller has satisfactory robust performance as well as robust stability by simulations and experiments.

• Toxicological Research
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• v.34 no.1
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• pp.31-39
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• 2018

The objective of this study was to evaluate the antioxidant and anti-aging effects of marigold methanol extract (MGME) in human dermal fibroblasts. Total polyphenolic and flavonoid contents in MGME were 74.8 mg TAE (tannic acid equivalent)/g and 85.6 mg RE (rutin equivalent)/g, respectively. MGME ($500{\mu}g/mL$) increased 1,1-diphenyl-2-picryl hydrazyl (DPPH) and 2,2'-azino-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical-scavenging, and superoxide dismutase (SOD)-like antioxidant activities by 36.5, 54.7, and 14.8%, respectively, compared with the control. At $1,000{\mu}g/mL$, these activities increased by 63.7, 70.6, and 20.6%, respectively. MGME ($100{\mu}g/mL$) significantly increased the synthesis of type 1 procollagen by 83.7% compared with control treatment. It also significantly decreased Matrix Metalloproteinase-2 (MMP-2) activity and MMP-1 mRNA expression by 36.5% and 69.5%, respectively; however, it significantly increased laminin-5 mRNA expression by 181.2%. These findings suggest that MGME could protect human skin against photo-aging by attenuating oxidative damage, suppressing MMP expression and/or activity as well as by stimulating collagen synthesis.

• Natural Product Sciences
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• v.16 no.2
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• pp.133-139
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• 2010

In order to develop a new skin whitening agent, approximately 100 plant extracts were evaluated for their inhibitory activities against melanin biosynthesis in cultured mouse melanocyte melan-a cells. As a result, seven extracts exhibited over 50% inhibition of melanin synthesis compared to control at a concentration of $20\;{\mu}g/ml$. In particular, Aster ageratoides Turcz. var. ageratoides (branch, root, aerial, flower; $IC_{50}$ = 17.3, 6.1, 13.6, $12.9\;{\mu}g/ml$, respectively) and Physalis alkekengi var. francheti (leaf, unripen fructus, aerial; $IC_{50}$ = 6.5, 28.3, $23.9\;{\mu}g/ml$) markedly inhibited melanin synthesis. In addition, tyrosinase activity was monitored by the measurement of dopachrome formation from the oxidation of L-3,4-dihydroxyphenylalanine. Extracts of A. ageratoides Turcz. var. ageratoides (flower) and P. alkekengi var. francheti (leaf) showed the most potent tyrosinase inhibitory activity. These plants might be the potential candidate sources in the development of novel skin-whitening products.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.31 no.1
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• pp.32-41
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• 2018

Objectives : Hyaluronic acid(HA) is a mucopolysaccharide, occuring naturally in living organisms. It is one of the most hydrophilic molecules, so it has been known as being related to skin hydration and skin aging. The purpose of this study is to examine the effects of Angelica gigas(A. gigas) ethanol extract on hyaluronic acid synthesis. Methods : To determine cytotoxicity and hyaluronic acid synthase 2 gene expression, hyaluronic acid production in HaCaT cells, MTT assay and RT-PCR ELISA was used. Results : There were no cytotoxicity in $50{\mu}g/ml$ concentration A. gigas extract in MTT assay. Hyaluronic acid synthase 2(HAS2) gene expression was increased by all treated concentration A. gigas extract. Hyaluronic acid production was higher than control group in $50{\mu}g/ml$ & $100{\mu}g/ml$ concentration A. gigas extract. Conclusions : Hyaluronic acid production was increased by A. gigas extracts. Therefore, We suggest that A. gigas can make a contribution to the moisturizing effect on human skin.