• Title/Summary/Keyword: fluorescence control

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Determination of Bumetanide in Human Plasma by a Validated HPLC Method and Its Application to Single-dose Pharmacokinetics (사람 혈장 중 부메타니드의 HPLC 분석법 검증 및 단일 용량 투여에 의한 약물동태 연구)

  • Park, Hae-Young;Gwak, Hye-Sun;Chun, In-Koo
    • Journal of Pharmaceutical Investigation
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    • v.35 no.1
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    • pp.51-55
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    • 2005
  • A high-performance liquid chromatographic method was employed for the determination of bumetanide in human plasma. After addition of internal standard (IS, naproxen) and acidification of the plasma with 1 M hydrochloric acid, the drug and IS were extracted into dichloromethane. The organic phase was back-extracted into 1 M sodium bicarbonate solution and 50 ${\mu}l$ of the aqueous phase was injected onto a reversed-phase C18 column with a mobile phase consisting of methanol: water: glacial acetic acid = 65 : 35 : 1. The samples were detected utilizing a fluorescence detector (excitation wavelength 235 nm, emission wavelength 405 nm). The method was specific and validated with a lower limit of 5 ng/mL. Intra- and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification. The applicability of the method was demonstrated by analysis of plasma after oral administration of a single 2 mg dose to 24 healthy subjects. From the plasma bumetanide concentration vs. time curves, the mean AUC was $246.5{\pm}73.8\;ng{\cdot}hr/mL$ and $C_{max}$ of $132.1{\pm}40.9$ ng/mL reached 1.2 hr after administration. The mean biological half-life of burnet ani de was $1.1{\pm}0.2$hr. Based on the results, this simple and validated assay method could readily be used in any pharmacokinetic or bioequivalence studies using humans.

Effect of Autophagy-Related Beclin1 on Sensitivity of Cisplatin-Resistant Ovarian Cancer Cells to Chemotherapeutic Agents

  • Sun, Yang;Liu, Jia-Hua;Jin, Long;Sui, Yu-Xia;Han, Li-Li;Huang, Yin
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.7
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    • pp.2785-2791
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    • 2015
  • The purpose of the study was to determine the effects of autophagy related gene Beclin1 at different levels of expression on the sensitivity of cisplatin-resistant ovarian cancer cells (SKOV3/DDP) to different chemotherapeutics. In pSUPER-Beclin1 transfected cells, real-time fluorescence quantitative RT-PCR and Western blot analysis showed that expression was significantly inhibited. Flow cytometry revealed that the mean fluorescence intensity (MDC), reflecting autophagy, and cells in the G0/G1 phase were markedly reduced. When compared with the blank control group, inhibition of Beclin1 expression in SKOV3/DDP cells not only increased the rate of apoptosis following treatment with chemotherapeutics, but also increased the sensitivity. These findings suggest that Beclin1 expression plays an important role in chemotherapeutic agent-induced death of SKOV3/DDP cells. Inhibition of autophagy related gene Beclin1 expression in SKOV3/DDP cells may increase the rate of apoptosis and elevate the sensitivity to chemotherapeutics.

The exceptionally large genome of the harmful red tide dinoflagellate Cochlodinium polykrikoides Margalef (Dinophyceae): determination by flow cytometry

  • Hong, Hyun-Hee;Lee, Hyun-Gwan;Jo, Jihoon;Kim, Hye Mi;Kim, Su-Man;Park, Jae Yeon;Jeon, Chang Bum;Kang, Hyung-Sik;Park, Myung Gil;Park, Chungoo;Kim, Kwang Young
    • ALGAE
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    • v.31 no.4
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    • pp.373-378
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    • 2016
  • Cochlodinium polykrikoides is a red-tide forming dinoflagellate that causes significant worldwide impacts on aquaculture industries and the marine ecosystem. There have been extensive studies on managing and preventing C. polykrikoides blooms, but it has been difficult to identify an effective method to control the bloom development. There is also limited genome information on the molecular mechanisms involved in its various ecophysiology and metabolism processes. Thus, comprehensive genome information is required to better understand harmful algal blooms caused by C. polykrikoides. We estimated the C. polykrikoides genome size using flow cytometry, with detection of the fluorescence of DNA stained with propidium iodide (PI). The nuclear genome size of C. polykrikoides was 100.97 Gb, as calculated by comparing its mean fluorescence intensity (MFI) to the MFI of Mus musculus, which is 2.8 Gb. The exceptionally large genome size of C. polykrikoides might indicate its complex physiological and metabolic characteristics. Our optimized protocol for estimating the nuclear genome size of a dinoflagellate using flow cytometry with PI can be applied in studies of other marine organisms.

Generation of a Constitutive Green Fluorescent Protein Expression Construct to Mark Biocontrol Bacteria Using P43 Promoter from Bacillus subtilis

  • Kong, Hyun-Gi;Choi, Ki-Hyuck;Heo, Kwang-Ryool;Lee, Kwang-Youll;Lee, Hyoung-Ju;Moon, Byung-Ju;Lee, Seon-Woo
    • The Plant Pathology Journal
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    • v.25 no.2
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    • pp.136-141
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    • 2009
  • Marking biocontrol bacteria is an essential step to monitor bacterial behavior in natural environments before application in agricultural ecosystem. In this study, we presented the simple green fluorescent protein (GFP) reporter system driven by the promoter active in Bacillus species for tagging of the biocontrol bacteria. A constitutive promoter P43 from Bacillus subtilis was fused to an enhanced promoterless gfp gene by overlap extension PCR. The GFP expression was demonstrated by the high fluorescence intensity detected in B. subtilis and Escherichia coli transformed with the P43-gfp fusion construct, respectively. The GFP reporter system was further investigated in two bacterial biocontrol strains B. licheniformis and Pseudomonas fluorescens. When the reconstructed plasmid pWH34G was introduced into B. licheniformis, GFP level measured with the fluorescence intensity in B. licheniformis was almost equivalent to that in B. subtilis. However, GFP expression level was extremely low in other biocontrol bacteria P. fluorescens by transposon based stable insertion of the P43-gfp construct into the bacterial chromosome. This study provides information regarding to the efficient biomarker P43-gfp fusion construct for bio-control Bacillus species.

Multidrug resistance reversal in mouse lymphoma cells by indian tea leaves, indian coffee seeds and chicory

  • Rao, Bhattiproulu Kesava;Motohashi, Noboru;Kawase, Masami;Spengler, Gabriella;Molnar, Joseph
    • Advances in Traditional Medicine
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    • v.3 no.2
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    • pp.100-105
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    • 2003
  • Systematic analysis of caffeine from the commercial samples of Indian tea leaves was performed by a routine method and the content of caffeine was found to be 19.0-37.4 mg/100 g leaves. The caffeine contents from coffee seeds and chicory from Indian origin were analyzed and found to be 0.6540-1.4920 g/100 g seeds. Caffeine contents of roasted Indian chicory roots were lower than either those of Indian tea leaves or Indian coffee seeds. The multidrug resistance (MDR) reversing effects were tested on a mouse leukemia cell line of L-5178 cells by methanol extracts [M1-M15] of Indian tea leaves and coffee seeds, comparing to a control of $({\pm})-verapamil$. The effects were measured by fluorescence ratio between treated and untreated group cells. Among fifteen methanol extracts, a Gemini tea [M6] (fluorescence activity ratio 5.26) had the most potent effect for L-5178 cells. The extract M6 was 0.63-fold of $({\pm})-verapamil$. We suggest that one of mechanisms of reversal by M6 might have strong affinity to dopamine $D_1$ and D_2$ receptors. Further studies with many more tumor and normal cell lines are necessary to confirm the MDR reversal specificity of coffee methanol extracts.

Antioxidant and Hepatoprotective Effects of Tomato Extracts

  • Rhim, Tae-Jin
    • Korean Journal of Plant Resources
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    • v.19 no.6
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    • pp.649-654
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    • 2006
  • The objective of present study was to investigate the anti oxidative and hepatoprotective effects of tomato extracts. Total antioxidant capacity and total antioxidant response were 5.5 and $19.8{\mu}g$ Trolox equivalent per mg of tomato extract, respectively. DPPH radical scavenging activity of tomato extracts ($10mg\;ml^{-1}$) was 70% as compared to 100% by pyrogallol solution as a reference. The effect of the tomato extracts on lipid peroxidation was examined using rat liver mitochondria induced by iron/ascorbate. Tomato extracts at the concentration of $0.5mg\;ml^{-1}$ significantly decreased TBARS concentration. Tomato extracts prevented lipid peroxidation in a dose-dependent manner. The effect of the tomato extracts on reactive oxygen species (ROS) generation was examined using cell-free system induced by $H_2O_2/FeSO_4$. Addition of $1mg\;ml^{-1}$ of tomato extracts significantly reduced dichlorofluorescein (DCF) fluorescence. Tomato extracts caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that tomato extracts significantly prevented ROS generation in vitro. The effect of tomato extracts on cell viability and proliferation was examined using hepatocyte culture. Primary cultures of rat hepatocytes were incubated with 1mM tert-butyl hydroperoxide (t-BHP) for 90 min in the presence or absence of tomato extracts. MTT values by addition of tomato extracts at the concentration of 2, 10, and $20mg\;ml^{-1}$ in the presence of t-BHP were 13, 33 and 48%, respectively, compared to 100% as control. Tomato extracts increased cell viability in a dose-dependent manner. These results demonstrate that tomato extracts suppressed lipid peroxidation and t-BHP-induced hepatotoxicity and scavenged ROS generation. Thus antioxidant and hepatoprotective effects of tomato extracts seem to be due to, at least in part, the prevention from free radicals-induced oxidation, followed by inhibition of lipid peroxidation.

Effect of Polymer Adhesive Film Supplemented 5% NaF on Enamel Remineralization (5% 불화나트륨을 함유한 고분자 접착필름의 법랑질 재광화효과)

  • Jih, Myeongkwan;Lee, Sangho;Lee, Nanyoung
    • Journal of the korean academy of Pediatric Dentistry
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    • v.41 no.3
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    • pp.218-224
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    • 2014
  • This study was designed to evaluate the effectiveness of 5% sodium fluoride-polyvinyl alcohol (NaF-PVA) tape influencing enamel remineralization by analysing enamel surface microhardness (SMH) and variation of ${\Delta}F$ of QLF. After enamel demineralizing of specimen, these 60 specimens with average KHN of microhardness ranging from 50 to 100 and with ${\Delta}F$ of QLF ranging from -15 to -25 were divided into four groups : group 1 (control group), group 2 (NaF-PVA), group 3 (fluoride varnish, FluoroDose$^{(R)}$ varnish), group 4 (Casein phosphopeptide-amorphous calcium phosphate, Tooth mousse plus$^{TM}$). These specimens were treated with materials and then immersed in artificial saliva. We measured remineralization rate each using surface microhardness (SMH) and Quantitative light-induced fluorescence digital (QLF-D). As a result, NaF-PVA tape is better than group 1, 4 and have comparable remineralization effect with group 3 (p < 0.05).

High Performance Liquid Chromatographic Assay of a New Fluoroquinolone, LB20304, in the Plasma of Rats and Dogs

  • Seo, Mi-Kyeong;Jeong, Yi-Na;Kim, Hoon-Joo;Kim, In-Chull;Lee, Yong-Hee
    • Archives of Pharmacal Research
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    • v.19 no.6
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    • pp.554-558
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    • 1996
  • High-performance liquid chromatographic method was developed for the determination or LB 20304 (compound 1) in the plasma of rats and dogs. The analyte was deproteinized with 1 volume of methanol and 1/2 volume of 10% zinc sulfate, and the supernatant was injected onto a reversed-phase HPLC column. The mobile phase was a mixture of 24 parts of acetonitrile and 76 parts of 0.1% trifluoroacetic acid. The flow rate was 1 ml/min, and the effluent was monitored by fluorescence detector at an excitation wavelength of 337 nm and an emission wavelength of 460 nm. The retention time of compound 1 was 6.3 min. The assay of compound 1 was linear over the concentration range of 0.2-100.mu.g/ml in the plasma of rats and dogs. The lower limit of quantification was 0.2.mu.g/ml using 100.mu.l of plasma with a 97-99% accuracy and a 12-14% precision. In the 0.5, 5, and 50.mu.g/ml quality control samples, the intra- and inter-day accuracy were 88-95% and 88-97%, whereas intra- and interday precision were 0.5-6.6% and 0.2-9.3%, respectively, in the plasma of rats and dogs. The recoveries were 68-71% independent of concentration and species in the plasma. No interferences from endogenous substances were observed. Taken together, the above HPLC assay method by deproteinization and fluorescence detection was suitable for the determination of compound 1 in the preclinical pharmacokinetics.

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Effects of Curcumin from Turmeric Supplementation in Freezing Buffer on Sperm Motilities and Reactive Oxygen Species Generation (동결보존액에 울금에서 추출한 Curcumin의 첨가가 정자의 운동성과 활성산소 생성에 미치는 영향)

  • Lee, Eun-Joo;Kim, Dae-Young
    • Journal of Embryo Transfer
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    • v.32 no.3
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    • pp.249-255
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    • 2017
  • In this experiment, we determined the effect of curcumin supplementation in freezing buffer for miniature pig sperm cryopreservation. Each ejaculate was diluted with modified Modena B extender and mixed with lactose-egg yolk (LEY extender, 80% v/v lactose solution [310 mM], 20% v/v egg yolk, and $100{\mu}g/mL$ kanamycin sulfate) and LEY-glycerol Orvus ES Paste (LEYGO, 89.5% v/v LEY, 5% v/v glycerol, 1.5% v/v Orvus ES Paste), 100 mM trehalose supplemented with 0, 10, 50, 100, and $500{\mu}M$ of curcumin from turmeric, respectively. Following equilibration, the 0.5 mL French straws were frozen and plunged into $LN_2$ tank for 7 days at least. Sperm parameter and oxidative byproducts were determined by the computer assisted sperm motility analysis (CASA) and fluorescence-activated cell sorting (FACS) as compared with each groups. Supplementation of curcumin had no effect on sperm motility, progressive motility and curvilinear velocity. However, average-path velocity and straight-line velocity were significantly higher in $10{\mu}M$ curcumin group ($100.9{\pm}8.8{\mu}m/s$, $61.7{\pm}2.9{\mu}m/s$, respectively) than control group ($77.8{\pm}3.9{\mu}m/s$, $46.4{\pm}3.0{\mu}m/s$, respectively) (p < 0.05). In addition, the level of the O2 radical and H2O2 were comparatively decreased in curcumin groups by evaluation of ethidium and DCF fluorescence. According to the results, curcumin can improve sperm kinetic variables and alleviate ROS induced cryoinjury to pig sperm.

Photoluminescent Graphene Oxide Microarray for Multiplex Heavy Metal Ion Analysis

  • Liu, Fei;Ha, Hyun Dong;Han, Dong Ju;Park, Min Su;Seo, Tae Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.281.2-281.2
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    • 2013
  • Since heavy metal ions included in water or food resources have critical effects on human health, highly sensitive, rapid and selective analysis for heavy metal detection has been extensively explored by means of electrochemical, optical and colorimetric methods. For example, quantum dots (QDs), such as semiconductor QDs, have received enormous attention due to extraordinary optical properties including high fluorescence intensity and its narrow emission peaks, and have been utilized for heavy metal ion detection. However, the semiconductor QDs have a drawback of serious toxicity derived from cadmium, lead and other lethal elements, thereby limiting its application in the environmental screening system. On the other hand, Graphene oxide (GO) has proven its superlative properties of biocompatibility, unique photoluminescence (PL), good quenching efficiency and facile surface modification. Recently, the size of GO was controlled to a few nanometers, enhancing its optical properties to be applied for biological or chemical sensors. Interestingly, the presence of various oxygenous functional groups of GO contributes to opening the band gap of graphene, resulting in a unique PL emission pattern, and the control of the sp2 domain in the sp3 matrix of GO can tune the PL intensity as well as the PL emission wavelength. Herein, we reported a photoluminescent GO array on which heavy metal ion-specific DNA aptamers were immobilized, and sensitive and multiplex heavy metal ion detection was performed utilizing fluorescence resonance energy transfer (FRET) between the photoluminescent monolayered GO and the captured metal ion.

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