• Title/Summary/Keyword: Fluorescence intensity

Search Result 577, Processing Time 0.026 seconds

Fluorescent Pattern Generation on the Fluorescent Photopolymer with 2-beam Coupling Method (2-beam Coupling 방법을 이용한 광 고분자 형광 패턴 형성)

  • Kim, Yoon-Jung;Kim, Jeong-Hun;Sim, Bo-Yeon;Lee, Myeong-Kyu;Kim, Eun-Kyoung
    • Korean Journal of Optics and Photonics
    • /
    • v.21 no.1
    • /
    • pp.6-11
    • /
    • 2010
  • Fluorescent photopolymer film was prepared with composition containing acrylate monomer, binder, a visible light sensitive photo initiator, and fluorescent anthracene polymer. A fluorescent grating pattern was inscribed on the photopolymer film using a 2-beam coupling method. A 514 nm laser was coupled to generate a beam-interference pattern. A highly fluorescent diffractive line pattern was formed on the fluorescent photopolymer within 30 sec. of exposure. The fluorescence intensity was highly enhanced in the patterned area, possibly due to the change in the environment of the fluorescent polymers by the photo-polymerization of monomers. Under a photo-mask, a gap electrode pattern was formed of fluorescent gratings with a sub-micron scale, which was matched well to the calculated value ($2.5\;{\mu}m$ and $0.6\;{\mu}m$) based on the refractive index of the photopolymer and beam incident angle ($3.4^{\circ}$, $15^{\circ}$) to the photopolymer surface.

The effects of zeatin on Cd2+ -induced physiological toxicities in Commelina communis L (Zeatin이 Cd2+에 의한 닭의장풀의 생리적 독성에 미치는 영향)

  • Lee Joon Sang
    • Journal of Environmental Science International
    • /
    • v.14 no.3
    • /
    • pp.345-350
    • /
    • 2005
  • Three-week old Commelina communis was transferred and grown in Hoagland solution containing $100{\mu}M\;Cd^{2+},\;100{\mu}M\;Cd^{2+}+100{\mu}M\;kinetin,\;100{\mu}M\;Cd^{2+}+100{\mu}M\;zeatin\;and\;100{\mu}M\;Cd^{2+},\;200{\mu}M$ zeatin for 7 days, and then a number of physiological activities were investigated. In control, the length of the stem of plants was increased to 4.7cm, but in $Cd^{2+},\;Cd^{2+}+kinetin,\; Cd^{2+}+100{\mu}M\;zeatin\;and\;Cd^{2+}+200{\mu}M$ zeatin treatments, the growth of plants were increased to 1.5cm, 2.1cm, 3.9cm and 4.3 em, respectively. In the treatments of $Cd^{2+},\;Cd^{2+}+kinetin,\;Cd^{2+}+100{\mu}M\;zeatin\;and\; Cd^{2+}+200{\mu}M$ zeatin, total chlorophyll contents were reduced to $26\%,\;24\%,\;15\%\;and\;3\%$, respectively, on the contrast to the control. In chlorophyll fluorescence experiments, Fv/Fm ratios were also reduced to $44\%,\;21\%,\;17\%\;and\;5\%$ in the light intensity of $2100{\mu}Mmole\;E\;m^{-2}s^{-1}\;by\;Cd^{2+},\;Cd^{2+}+kinetin,\;Cd^{2+}+$100{\mu}M\;zeatin\;and\;Cd^{2+}+200{\mu}M$ zeatin treatments on the contrast to the control. Water stresses were increased to 2.6, 1.7 and 1.2 times by $Cd^{2+},\; Cd^{2+}+kinetin\;and\;Cd^{2+}+{\mu}M$ zeatin. On the other hand, combination of $Cd^{2+}+200{\mu}M$ zeatin reduced water stress to $0.12\%$. In $Cd^{2+}$ accumulation experiments $Cd^{2+}$transports were inhibited to $33\%\; 48\%\;and\;70\%\;by\;Cd^{2+}+kinetin,\;Cd^{2+}+100{\mu}M\;zeatin\;and\;Cd^{2+}+200{\mu}M$ zeatin. Therefore, it could be concluded that zeatin clearly reduced the toxicities of $Cd^{2+}$ by reducing the absorption of $Cd^{2+}$.

Hypoxia Induced Multidrug Resistance of Laryngeal Cancer Cells via Hypoxia-inducible Factor-1α

  • Li, Da-Wei;Dong, Pin;Wang, Fei;Chen, Xin-Wei;Xu, Cheng-Zhi;Zhou, Liang
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.8
    • /
    • pp.4853-4858
    • /
    • 2013
  • Objectives: To investigate whether hypoxia has an effect on regulation of multidrug resistance (MDR) to chemotherapeutic drugs in laryngeal carcinoma cells and explore the role of hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$). Methods: Laryngeal cancer cells were cultured under normoxic and hypoxic conditions. The sensitivity of the cells to multiple drugs and levels of apoptosis induced by paclitaxel were determined by MTT assay and annexin-V/propidium iodide staining analysis, respectively. HIF-$1{\alpha}$ expression was blocked by RNA interference. The expression of HIF-$1{\alpha}$ gene was detected by real-time quantitative RT-PCR and Western blotting. The value of fluorescence intensity of intracellular adriamycin accumulation and retention in cells was evaluated by flow cytometry. Results: The sensitivity to multiple chemotherapy agents and induction of apoptosis by paclitaxel could be reduced by hypoxia (P<0.05). A the same time, the adriamycin releasing index of cells was increased (P<0.05). However, resistance acquisition subject to hypoxia in vitro was suppressed by down-regulating HIF-$1{\alpha}$ expression. Conclusion: HIF-$1{\alpha}$ could be considered as a key regulator for mediating hypoxia-induced MDR in laryngeal cancer cells via inhibition of drug-induced apoptosis and decrease in intracellular drug accumulation.

Ethanol-eluted Extract of Rhus verniciflua Stokes Inhibits Cell Growth and Induces Apoptosis in Human Lymphoma Cells

  • Lee, Jeong-Chae;Kim, Ju;Jang, Yong-Suk
    • BMB Reports
    • /
    • v.36 no.4
    • /
    • pp.337-343
    • /
    • 2003
  • Rhus verniciflua Stokes (RVS) has been used as a traditional herbal medicine. Several earlier studies indicated that an ethanol extract of RVS has both anti-oxidant and anti-tumor properties, although the mechanism for the activity remains to be elucidated. In this report, we prepared a highly purified ethanol extract from RVS, named REEE-1 ($\underline{R}$hus $\underline{e}$thanol $\underline{e}$luted $\underline{e}$xtract-1), and investigated the mechanism involved in its growth-inhibitory effect on the human B and T lymphoma cell lines, BJAB and Jurkat, respectively. Results from tritium uptake proliferation assays showed that the proliferative capacities of both BJAB and Jurkat cells were strongly suppressed in the presence of REEE-1. This was further confirmed through trypan blue exclusion experiments that revealed a dose-dependent decrease in viable cell numbers after REEE-1 treatment. REEE-1-mediated suppression of cell growth was verified to be apoptotic, based on the increase in DNA fragmentation, low fluorescence intensity in nuclei after propidium iodide staining, and the appearance of DNA laddering. In particular, REEE-1 exerted its anti-oxidant activity through the inhibition of hydroxyl radical-mediated degradation by iron ion chelation rather than direct scavenging of hydroxyl radicals. Furthermore, REEE-1 was revealed to be a potential scavenger of superoxide anions. Collectively, our findings suggest that REEE-1 is a natural anti-oxidant that could be used as a cancer chemo-preventive and therapeutic agent.

Functionality Changes of Rapeseed Protein upon Proteolysis (유채단백질의 Proteolysis에 의한 기능성 변화)

  • Kim, Chung-Hee;Kim, Hyo-Sun;Lee, Jang-Soon
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.21 no.5
    • /
    • pp.519-524
    • /
    • 1992
  • purified rapeseed(Brassica napus var. Youngsan) protein was hydrolyzed by pronase. The hyrolysate protein was investigated for the some physicochemical and functional properties. UV and intrinsic fluorescence spectra of the hydrolysate showed the maximum absorption at 274nm and 360nm respectively. Intensity of yellow color decreased in the process of hydrolysis and the surface hydrophobicity decreased up to fourfold. The main bands of hydrolysate by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) were observed at 14,000 to 12,000 dalton molecular weight. Solubilities of hydrolyzed protein increased by 10~15% compared to those of unhydrolyzed protein at acidic pH. In the hydrolysate, while absorption of both water and oil, foam expansion and emulsion stability were increased, absolute viscosity, heat coagulation, calcium coagulation, foam stability and emulsion activity were decreased.

  • PDF

Luminescence Studies of N-Methyllutidone, an Unusually High Triplet Energy Sensitizer (N-메틸루티돈의 루미네센스에 관한 연구)

  • Sang Chul Shim;Myung Ho Hyun;Kuy Ho Chae
    • Journal of the Korean Chemical Society
    • /
    • v.22 no.1
    • /
    • pp.45-51
    • /
    • 1978
  • The luminescence of N-methyllutidone is studied in ethanol matrix at $77^{\circ}C$K. No fluorescence is observed but a strong phosphorescence with the quantum yield of 0.1 and the lifetime of 0.2 sec is recorded. An unusually high triplet energy of 85.1 kcal/mole is determined for the compound from the O-O band of phosphorescence. The cis ${\leftrightarrow}$ trans photoisomerization of high triplet energy olefins such as 2-hexene and trans-1,4-dichlorobutene-2 is efficiently sensitized by N-methyllutidone substantiating the high triplet energy of the compound. The negative polarization of O-O band reveals the emitting triplet state to be $({\pi},{\pi}^*)^3$ state. Alkaline metal salts such as lithium chloride enhances the phosphorescence intensity through cation-N-methyllutidone coordination widening the gap between $({\pi},{\pi}^*)^3$and $(n,{\pi}^*)^3$ states.

  • PDF

Generation of Reactive Oxygen Species and Subsequent DNA Fragmentation in Bovine Cultured Somatic Cells

  • Hwang, In-Sun;Kim, Ho-Jeong;Park, Chun-Keun;Yang, Boo-Keun;Cheong, Hee-Tae
    • Reproductive and Developmental Biology
    • /
    • v.35 no.4
    • /
    • pp.485-489
    • /
    • 2011
  • The present study was conducted to examine the reactive oxygen species (ROS) generation levels and subsequent DNA damage in the bovine cultured somatic cells. Bovine ear skin cells were classified by serum starvation, confluence and cycling cells. Cells were stained in 10 ${\mu}M$ dichlorohydrofluorescein diacetate ($H_2DCFDA$) or 10 ${\mu}M$ hydroxyphenyl fluorescein (HPF) dye to measure the $H_2O_2$ or $^{\cdot}OH$ radical levels. The samples were examined with a fluorescent microscope, and fluorescence intensity was analyzed in each cell. $H_2O_2$ and $^{\cdot}OH$ radical levels of cultured somatic cells were high in confluence group ($7.1{\pm}0.7$ and $8.4{\pm}0.4$ pixels/cell, respectively) and significantly low in serum starvation group ($4.9{\pm}0.4$ and $7.0{\pm}0.4$ pixels/cell, respectively, p<0.05). Comet tail lengths of serum starvation ($148.3{\pm}5.7$ ${\mu}M$) and confluence ($151.1{\pm}5.0$ ${\mu}M$) groups were found to be significantly (p<0.05) increased in comparison to that of cycling group ($137.1{\pm}7.5$ ${\mu}M$). These results suggest that the culture type of donor cells can affect the ROS generation, which leads the DNA fragmentation of the cells.

Generation of Reactive Oxygen Species in Porcine Parthenogenetic Embryos

  • Hwang, In-Sun;Park, Choon-Keun;Yang, Boo-Keun;Cheong, Hee-Tae
    • Reproductive and Developmental Biology
    • /
    • v.35 no.2
    • /
    • pp.191-195
    • /
    • 2011
  • The present study was conducted to examine the reactive oxygen species (ROS) generation levels in porcine parthenogenetic embryos. Porcine in vitro matured oocytes were activated by the combination of electric stimulus and 6-DMAP before in vitro culture. Porcine oocytes and parthenogenetic embryos were stained in 10 ${\mu}M$ dichlorohydrofluorescein diacetate (DCF) or 10 ${\mu}M$ hydroxyphenyl fluorescein (HPF) dye each for 30 min at $39^{\circ}C$. The fluorescent emissions from the samples were recoded as JPEG file and the intensity of fluorescence in oocytes and embryos were analyzed. $H_2O_2$ and $^{\cdot}OH$ radical levels of porcine oocytes were reduced immediately after electric stimulation. However, $H_2O_2$ and $^{\cdot}OH$ radical levels of parthenogenetic embryos were increased with time elapsed after electric stimulation from 0 h to 3 h and after DMAP culture. During in vitro culture, $H_2O_2$ and $^{\cdot}OH$ radical levels were gradually increased from the one-cell stage to the two- and four-cell stages. The result of the present study suggests that the ROS was not increased by electric pulse in porcine embryos. Rather than it seems to be associated with the stage of development and the culture condition.

Effect of Farnesyltransferase Inhibitor R115777 on Mitochondria of Plasmodium falciparum

  • Ha, Young Ran;Hwang, Bae-Geun;Hong, Yeonchul;Yang, Hye-Won;Lee, Sang Joon
    • Parasites, Hosts and Diseases
    • /
    • v.53 no.4
    • /
    • pp.421-430
    • /
    • 2015
  • The parasite Plasmodium falciparum causes severe malaria and is the most dangerous to humans. However, it exhibits resistance to their drugs. Farnesyltransferase has been identified in pathogenic protozoa of the genera Plasmodium and the target of farnesyltransferase includes Ras family. Therefore, the inhibition of farnesyltransferase has been suggested as a new strategy for the treatment of malaria. However, the exact functional mechanism of this agent is still unknown. In addition, the effect of farnesyltransferase inhibitor (FTIs) on mitochondrial level of malaria parasites is not fully understood. In this study, therefore, the effect of a FTI R115777 on the function of mitochondria of P. falciparum was investigated experimentally. As a result, FTI R115777 was found to suppress the infection rate of malaria parasites under in vitro condition. It also reduces the copy number of mtDNA-encoded cytochrome c oxidase III. In addition, the mitochondrial membrane potential (${\Delta}{\Psi}m$) and the green fluorescence intensity of MitoTracker were decreased by FTI R115777. Chloroquine and atovaquone were measured by the mtDNA copy number as mitochondrial non-specific or specific inhibitor, respectively. Chloroquine did not affect the copy number of mtDNA-encoded cytochrome c oxidase III, while atovaquone induced to change the mtDNA copy number. These results suggest that FTI R115777 has strong influence on the mitochondrial function of P. falciparum. It may have therapeutic potential for malaria by targeting the mitochondria of parasites.

Characteristics of flow field of nose-only exposure chamber for inhalation toxicity evaluation (흡입독성평가를 위한 비부노출 챔버의 유동흐름 특성)

  • Noh, Hakjae;Bong, Choonkeun;Bong, Hakyung;Kim, Yonggu;Cho, Myunghaing;Kim, Sanghwa;Kim, Daesung
    • Particle and aerosol research
    • /
    • v.12 no.1
    • /
    • pp.1-9
    • /
    • 2016
  • In this work, we evaluated the characteristics of flow field and uniformity of the nose-only exposure chambers for the inhalation toxicity test. Computational fluid dynamics (CFD) modeling was carried out to demonstrate uniformity of the nose-only exposure chambers. Because it is very important in the inhalation toxicity experiments that test materials are distributed uniformly to each holder of the chamber. The test was done with these 3 types of chamber with different form to develop inhalation toxicity evaluation system, easy-to-operate system among exposure chamber used for evaluating inhalation toxicity of environmental chemical mixtures. Through CFD interpretation, nose-only exposure chamber was made with the selection of the optimal conditions. For its evaluation, one type of fragrance was selected and measured particle size distribution of each port. The gene becoming luminous to green fluorescence was combined with GPT-SPE, a type of tGFP vector, to be inhaled to the mouse. Based on this, luminous intensity was checked. As a result, total particle number concentration of each port had average value of $3.17{\times}10^6{\sharp}/cm^3$ and range of the highest and lowest concentration value was approximately ${\pm}4.8%$. Autopsy of lung tissues of mouse showed that it had clearly better delivery of gene compared to the control group.