• Title/Summary/Keyword: fluorometry

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P18 Nitric Oxide and Hypoxia Affect TCDD Induced EROD Activity

  • Kim, Yeo W.;Cha Y. Baek;Hong K. Min;Yhun. Y. Sheen
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.138-138
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    • 1998
  • Effects of nitric oxide and hypoxia on ethoxyresorufin deethylase in Hepa I cells and MCF-7 human breast cancer cells were examined. TCDD treatment have resulted in the stimulation of ethoxyresorufin deethylase activity based on fluorometry in Hepa I in dose and time dependent manner. 0.1 nM TCDD showed maximal stimulation of ethoxyresorufin deethylase activity and 24 hour treatment also showed maximal stimulation of ethoxyresorufin deethylase activity. In MCF-7 human breast cancer cells, untreated cells showed high basal level of ethoxyresorufin deethylase activity. TCDD treatment to MCF-7 cells resulted minor stimulation of ethoxyresorufin deethylase activity compared to that in Hepa I cells. Nitric oxide and hypoxia inhibit TCDD effects on ethoxyresorufin deethylase activity in both cell lines. And also flavonoids, such as quercetin showed an inhibition of ethoxyresorufin deethylase activity that is stimulated with TCDD or 3-Methylcholanthrene. Estrogen and estrogen metabolite such as 16 a-estriol and 2-hydroxyestradiol also affects the ethoxyresorufin deethylase activity in MCF-7 cells.

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Photosynthetic Characteristics of Porphyra yezoensis Ueda Measured in situ by Diving Pulse-Amplitude Modulated (PAM) Fluorometry on the Southwestern Coast of the Korean Peninsula (남서해역에서 양식되는 방사무늬김(Porphyra yezoensis Ueda)의 Diving-PAM에 의한 광합성 특성)

  • Kim, Jeong Bae;Lee, Won-Chan;Kim, Hyung Chul;Choi, Hee-Gu;Park, Jung-Im;Cho, Yoonsik;Park, Hwan Hee
    • Korean Journal of Environmental Biology
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    • v.30 no.3
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    • pp.210-218
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    • 2012
  • The morphological characteristics, carbon and nitrogen concentrations, stable isotope values and photosynthetic rates of Porphyra yezoensis were studied at the main purple lavers production areas on southwestern coast of Korea. The morphological characteristics of leaf length, leaf width and weight of Porphyra blades were between 11.6~16.3 (average 13.8) cm, 4.6~6.3 (average 5.4) cm, $1.1{\sim}2.6(average\;1.86)g\;DW\;m^{-2}$, respectively. Photosynthetic pigment of Chl a concentration of Porphyra blades was between $2.18{\sim}17.77(average\;9.65)mg\;DW\;Chl\;a\;m^{-2}$. Carbon and nitrogen concentrations of Porphyra blades was between $201{\sim}317(average\;240)mg\;DW\;g^{-1}$, $39.8{\sim}50.0(average\;43.5)mg\;DW\;g^{-1}$ and C/N ratio 5.0~6.7 (average 5.5). The range of average ${\delta}^{13}C$ and ${\delta}^{15}N$ values of Porphyra blades was between - 25.6 to - 24.0 (average - 24.7)‰ for ${\delta}^{13}C$, and 1.3 to 4.1 (average 2.1)‰ for ${\delta}^{15}N$. Photosynthetic characteristics of seaweeds measured by pulse amplitude modulation (PAM) fluorometry was used as an indicator of photosynthetic activity. We use Diving-PAM fluorometry to examine photosynthetic rates of the seaweeds Porphyra yezoensis at each station. Maximum quantum yield of Porphyra blades was between 0.46~0.55 (average 0.52), the variance of the effective PS II maximum quantum yield of the station was broadly similar. Maximum relative electron transport rate (rETRmax) of Porphyra blades was between $4.71{\sim}5.84(average\;5.33){\mu}mol\;electrons\;m^{-2}\;s^{-1}$, the changes of maximum relative electron transport rate (rETRmax) of Porphyra yezoensis were similar to those of PS II maximum quantum yield. Photosynthetic efficiency (${\alpha}$) was between 0.027~0.045 (average 0.036). Minimum saturating irradiance ($E_k$) range was $139{\sim}180(average\;156){\mu}mol\;photons\;m^{-2}\;s^{-1}$. Minimum saturating irradiance ($E_k$) made a difference by station within the area on southwestern coast. Carbon and nitrogen concentrations and photosynthetic rates of Porphyra blades production areas on southwestern coast were broadly similar. The photosynthetic characteristics showed low photosynthetic rates because the low maximum quantum yields and low maximum relative electron transport rate.

Regulation of GFP Expression Using the Tetracycline Inducible Retroviral Vector System (Tetracycline Inducible Retrovirus Vector System에 의한 GFP 유전자의 발현 조절)

  • Koo Bon Chul;Kwon Mo Sun;Kim Teoan
    • Reproductive and Developmental Biology
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    • v.29 no.1
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    • pp.57-62
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    • 2005
  • One of the critical problems to be solved in transgenic animal production is uncontrollable constitutive expression of foreign genes, which usually results in serious physiological disturbances in the transgenic animal. To circumvent this problem, we constructed and tested two retrovirus vectors designed to express the GFP(green fluorescent protein) gene under the control of the tetracycline-inducible promoters. To maximize the GFP gene expression at turn-on state, WPRE(woodchuck hepatitis virus posttranscriptional regulatory element) sequence was introduced into the retrovirus vectors at downstream region of either the GFP gene or the sequence encoding rtTA(reverse tetracycline-controlled transactivator). Transformed cells were cultured in the medium supplemented with or without doxycycline(tetracycline derivative) for 48 hours, and induction efficiency was measured by comparing the GFP gene expression level using fluorometry and western blotting. Higher GFP expression was observed from the vector carrying the WPRE sequence at 3' side of the GFP gene, while tighter expression control(up to 20 fold) was obtained from the vector in which the WPRE sequence was placed at 3' side of rtTA sequence. The resulting tetracycline inducible vector system may be used in transgenic animal production and gene therapy.

Antioxidant Effect of Korean Red Ginseng Extract on Aqueous Linoleic Acid and LDL (수용성계의 Linoleic Acid와 LDL에 대한 한국산 홍삼의 산화방지효과)

  • Lee, J.W.;Lee, S.K.;Do, J.H.;Sung, H.S.;Lee, H.O.
    • Applied Biological Chemistry
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    • v.40 no.4
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    • pp.283-288
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    • 1997
  • The antioxidant activities of Korean Red Ginseng Extract(RGE) and ${\alpha}-tocopherol$, as reference compound, were tested with HPLC and fluorometry which measure the MDA after reacting an aqueous 1% linoleic acid buffer solution, and LDL(1 mg protein/ml) buffer solution with $H_2O_2{\;}and{\;}FeCl_2$. The generation of conjugated-diene in LDL(0.25 mg protein/ml) was also measured by spectrometry. MDA determination showed the antioxidant effect on linoleic acid oxidation with oxidation inhibition ratio of 71.8% and 76.1%, respectively, by addition of 1000 ppm RGE and 100 ppm ${\alpha}-tocopherol$. LDL(1 mg protein/ml) oxidation was inhibited by 25.2% and 21.2%, respectively, by addition of 200 ppm REG and 100 ppm ${\alpha}-tocopherol$. The generation of conjugated diene in LDL(0.25 mg protein/ml) was also inhibited by 44.2%, by addition of 50 ppm RGE.

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Contents of Phytic Acid and Minerals of Rice Cultivars from Korea

  • Lee, Heok-Hwa;Rhee, Hae-ik;Lee, Sang-Young;Kim, Chon-Ho;Park, Yong-Soon
    • Preventive Nutrition and Food Science
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    • v.2 no.4
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    • pp.301-303
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    • 1997
  • To elucidate the contents of phytic acid and minerals in rice produced in Korea, samples of 68 verieties of brown rice and 9 varieties of polished rice were analyzed for phytic acid by colorimetric method, and Ca, Fe, Mg and Zn contents by the atomic absorption spectrophytometer. Selenium was measured by fluorometry. Averages of phytic acid content of the 68 brown rice were 12.6 g/kg, whereas that of the 8 polished rice were 1.83 g/kg on dry matter. Averages of Ca, Fe, Mg and Zn contents on the 68 brown rice were 111, 7.4, 1,068 and 19.1 mg/kg, and those of the polished rice were 45.6, 2.1, 250 and 14 mg/kg, respectively. A averge of selenium content of the brown rice was 38.3 $\mu\textrm{g}$/kg.

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STUDY CYTOCHROME P450IA1 GENE EXPRESSION BY RTPCR.

  • Lee, Soo-Young;Yhun Y. Sheen
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1995.04a
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    • pp.128-128
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    • 1995
  • To investigate the mechanism of the regulation of cytochrome P450IA1 gene expression, ethoxyresorufin deethylase(EROD) and benzo(a)pyrene hydroxylase in B6 mouse liver, in isolated perfused rat liver system. and in B6 mouse hepatocyte Hepa-I cells were examined. In C57BL/6N mouse, 3-methylcholan- throne( 3MC ) treatment have resulted in the stimulation of EROD activity based on fluorometry by 2.79 fold comparirng with that of control. Measurement of mRNA of cytochrome P450 was carried out by either nothern blot or dot blot analysis. Findings are similar to that of studies with enzymes. Furhtermore, when RTPCR method was applied to detect mRNA in Hepa I cell and liver tissues the results were more clear. Cytochrome P450IA1 upstream DNA containing CAT construct was transfected into Hepa-1 cells. After transfection of CAT construct, 3MC and flavonoids, such as, chrysin, hesperetin, kaempferol, morin, myricetin and aminoyrine were treated. 48 Hours after treatments, cells were harvested and assayed for CAT mRNA by RTPCR. 3MC treatment to hepa I cells transfected with trout P450IA1-CAT construct increased CAT mRNA by 2.81 fold when it was compared with that of control. This increase CAT mRNA was decreased by concomitantly treated flavonoids and aminopyrine. The level of CAT protein was 29.2-58.0% of 3MC stimulated CAT protein. Results of this study suggested that RTPCR seems to be a very good method to study regulation of gene expression in liver tissue or Hepa cells.

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Form, Function and Longevity in Fucoid Thalli: Chlorophyll a Fluorescence Differentiation of Ascophyllum nodosum, Fucus vesiculosus and F. distichus (Phaeophyceae)

  • Kim, Kwang-Young;Garbary, David j
    • ALGAE
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    • v.24 no.2
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    • pp.93-104
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    • 2009
  • Imaging-PAM fluorometry was used to assess the chlorophyll a fluorescence parameter ${\Phi}_{PSII}$ (effective quantum yield) in Frcus vesiculosus. F. disttchus. ssp. distichus and AscophyIIum nodosum. The objective was to show variadon in fluorescence yield associated with age and frond organ, and to illustrate the spatial scales at which photosynthetic parameters vary on fucoid thalli. In addition, our species represented taxa in different but related genera, species with different ecoloeies (rock pool and non rock pool species), morphologies (with and without air bladders) and longevities (several to 20 or more years). A further objective was to determine the extent to which photosynthetic parameters reflected these differences- Effective quantum yield declined substantially with age in F. vesiculosus and F. distichus ssp. distichus, whereas ${\Phi}_{PSII}$ in A. nodosum was maximal after three years. In A. nodosum ${\Phi}_{PSII}$ was still high in branch segments at least seven years old. Older branches of A. nodosum showed relatively higher and more homogeneous photosynthetic capacity relative to Fucus species. Surfaces of air bladders in A. nodosum and F. vesicu- losus had ${\Phi}_{PSII}$ that was not significantly different from the highest rates, achieved in these species. The heterogene- ity of photosynthetic efficiency is consistent with morphological and developmental differences among the species and their ecology. in particular the longevity of A. nodosum fronds.

Determination of Total Phenolic Compounds from the Fruit of Rubus coreanum and Antioxidative Activity (복분자 열매의 총 페놀성분의 정량 및 항산화 활성)

  • 이종원;도재호
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.5
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    • pp.943-947
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    • 2000
  • The purpose of this study was to investigate the extraction method of phenolic compounds from Rubus coreanum and antioxidative activity. antioxidative activities of Rubus coreanum were tested with ability of donating hydrogen to DPPH, and HPLC, fluorometry which measure the amount of MDA after reacting linoleic acid with $H_2O$$_2$, and LDL with $H_2O$$_2$ and FeCl$_2$. The most suitable extraction conditions of the phenolic compounds from Rubus coreanum was 3 times with 60% ethanol, and the yield of extract containing 35% moisture was 15.28%. In extraction efficacy of phenolic compounds, 60% ethanol was superior to water as extraction solvent, and extraction efficacy with 60% ethanol did not differ from disolving by water after evaporation of 60% ethanol extract. 60% ethanol extract of Rubus coreanum had an ability of hydrogen donating to DPPH, MDA determination showed the antioxidative effect with inhibition ratio of 77.91% on linoleic acid oxidation by addition of Rubus coreanum extract with the concentration of 1.500 ppm. and about 65.74% of LDL oxidation was inhibited by addition of 1,000 ppm.

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Fluorescence Spectroscopy Studies on Micellization of Poloxamer 407 Solution

  • Lee, Ka-Young;Shin, Sang-Chul;Oh, In-Joon
    • Archives of Pharmacal Research
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    • v.26 no.8
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    • pp.653-658
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    • 2003
  • It has been reported that at low temperature region, poloxamers existed as a monomer. Upon warming, an equilibrium between unimers and micelles was established, and finally micelle aggregates were formed at higher temperature. In this study, the fluorescence spectroscopy was used to study the micelle formation of the poloxamer 407 in aqueous solution. The excitation and emission spectra of pyrene, a fluorescence probe, were measured as a function of the concentration of poloxamer 407 and temperature. A blue shift in the emission spectrum and a red shift in the excitation spectrum were observed as pyrene transferred from an aqueous to a hydrophobic micellar environment. From the $I_1/I_3 and I_{339}/I_{333}$ results, critical micelle concentration (cmc) and critical micelle temperature (cmt) were determined. Also, from the fluorescence spectra of the probe molecules such as 8-anilino-1-naphthalene sulfonic acid and 1-pyrenecarboxaldehyde, the blue shift of the $\lambda_{max}$ was observed. These results suggest a decrease in the polarity of the microenvironment around probe because of micelle formation. The poloxamer 407 above cmc strongly complexed with hydrophobic fluorescent probes and the binding constant of complex increased with increasing the hydrophobicity of the probe.

Serum Kynurenic Acid: Possible Association with Invasiveness of Non-small Cell Lung Cancer

  • Sagan, Dariusz;Kocki, Tomasz;Kocki, Janusz;Szumilo, Justyna
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.9
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    • pp.4241-4244
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    • 2012
  • The lung adenocarcinoma is considered more aggressive than other types of non-small cell lung cancer. As metabolites of tryptophan degradation along the kynurenine pathway, including kynurenic acid, have been shown to induce immunosuppression and facilitate escape of tumor cells from immune surveillance, a hypothesis was set up that differences in biological behavior between types of lung cancer may be associated with altered activity of the kynurenine metabolic pathway. The aim of the study was to determine kynurenic acid levels in the serum of patients with bronchial adenocarcinoma for comparison with other types of non-small cell lung cancer. A total of 227 patients with non-small cell lung cancer were enrolled in the study, including 71 with adenocarcinoma and 96 with squamous cell carcinoma. Serum kynurenic acid concentration was determined with use of high performance liquid chromatography and fluorometry. The level of kynurenic acid in the serum of patients with adenocarcinoma was significantly higher than in those with squamous cell lung cancer ($107.1{\pm}62.8$ pmol/ml; 95%CI: 92.4 to 132.3 pmol/ml versus $82.1{\pm}47.6$ pmol/ml; 95%CI: 78.5 to 91.2 pmol/ml, respectively; p = 0.027). Differences between other histological types of lung cancer were insignificant. We conclude that increased activity of kynurenine metabolic pathway manifested by elevated serum kynurenic acid level may be one of the factors associated with clinically distinct biological behavior of adenocarcinoma, in particular high invasiveness and rapid progression.