• 환경생물
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• 제19권3호
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• pp.218-222
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• 2001

3주간 생장한 닭의장풀을 Hoagland용액 $(\pm{100\mu{M}\;Cd^{2+}$ 또는 $100\mu{M}\;Cd^{2+}+100\mu{M\; SA)$에서 4일 동안 수경 재배한 후 $Cd^{2+}$ 및 살리실릭산(SA) 처리시, 닭의장풀의 뿌리와 분리 표피에서의 $Cd^{2+}$ 농도와 nonprotein-SH 합성을 측정하였다. $Cd^{2+}$ 처리구에서는 $98\mu{M}\;Cd^{2+}/g.fr.wt$이 검출되었다. 이는 대조구에 비해 약 6배 증가한 것이다. $Cd^{2+}$을 SA와 같이 처리한 경우$Cd^{2+}$만 처리한 경우보다 뿌리에서 약 1.2배의 $Cd^{2+}$이 증가하였다. $Cd^{2+}$처리는 nonprotein-SH농도를 약 2배 이상 증가시켰다. $Cd^{2+}$을 SA와 같이 처리한 경우 $Cd^{2+}$만 처리한 경우보다 뿌리에서 nonprotein-SH농도는 약 2배 증가되었다. 분리표피에서 $Cd^{2+}$+SA 처리는 $Cd^{2+}$ 처리구에 비해 $Cd^{2+}$농도를 약 1.1배 증가시켰으며, 뿌리에서는 약 1.2배 증가시켰다. Nonprotein-SH도 합성도 뿌리와 비슷하게 $Cd^{2+}$농도에 의존하며 증가되었으며, $Cd^{2+}$+SA처리는 nonprotein-SH합성을 $Cd^{2+}$처리구에 비해 약 2배 증가시켰다. 위 결과로부터 신호전달물질인 SA처리는 $Cd^{2+}$ 흡수를 촉진시키며, 아울러 non-protein-SH 합성 과정에도 영향을 주는 것으로 사료된다.

• 한국산업보건학회지
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• 제10권2호
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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.

• 한국환경농학회지
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• 제20권5호
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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.

• 환경위생공학
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• 제14권1호
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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.

• 한국응용과학기술학회지
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• 제27권1호
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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.

• 미생물학회지
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• 제29권1호
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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.

• 전자공학회논문지T
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• 제36T권3호
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• pp.41-49
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• 1999

본 논문에서는 μ-합성법으로 제어기를 설계하여 센서와 구동부가 동일위치에 있지 않은(noncollocated) 탄성-질량 시스템에 적용한다. 스프링 상수값과 제어대상의 부하 질량은 불확실하다고 가정한다 매개변수 불확실성을 포함하고 있는 제어대상은 상태 공간 방정식, 특히 묘사형(descriptor form)을 사용하여 모델링 한다. μ-합성법으로 설계된 H/sub ∞/ 제어기를 표준 H/sub ∞/ 제어기와 비교한다. 두 개의 H/sub ∞/ 제어기 성능을 비교하기 위해, μ-합성 제어기가 구조적 불확실성을 가지고 있다는 것을 제외하고는 서로 동일한 하중함수를 가지고 설계한다. 표준 H/sub ∞/ 제어기와 비교하여 설계된 제어기는 만족스러운 강건 안정성과 강건 성능을 가지는 것을 시뮬레이션과 실험을 통해 확인한다.

• Toxicological Research
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• 제34권1호
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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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• 제16권2호
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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.

• 한방안이비인후피부과학회지
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• 제31권1호
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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.