• Title/Summary/Keyword: fluorescein

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Data Mining for Detection of Diabetic Retinopathy

  • Moskowitz, Samuel E.
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2003.09a
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    • pp.372-375
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    • 2003
  • The incidence of blindness resulting from diabetic retinopathy has significantly increased despite the intervention of insulin to control diabetes mellitus. Early signs are microaneurysms, exudates, intraretinal hemorrhages, cotton wool patches, microvascular abnormalities, and venous beading. Advanced stages include neovascularization, fibrous formations, preretinal and vitreous microhemorrhages, and retinal detachment. Microaneurysm count is important because it is an indicator of retinopathy progression. The purpose of this paper is to apply data mining to detect diabetic retinopathy patterns in routine fundus fluorescein angiography. Early symptoms are of principal interest and therefore the emphasis is on detecting microaneurysms rather than vessel tortuosity. The analysis does not involve image-recognition algorithms. Instead, mathematical filtering isolates microaneurysms, microhemorrhages, and exudates as objects of disconnected sets. A neural network is trained on their distribution to return fractal dimension. Hausdorff and box counting dimensions grade progression of the disease. The field is acquired on fluorescein angiography with resolution superior to color ophthalmoscopy, or on patterns produced by physical or mathematical simulations that model viscous fingering of water with additives percolated through porous media. A mathematical filter and neural network perform the screening process thereby eliminating the time consuming operation of determining fractal set dimension in every case.

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Specific Targeting of Fluorescein Isothiocyanate with Ep-CAM Antibody(Specific targeting of FITC with Ep-CAM Antibody)

  • Lee, Young-Tae;Tae, Gun-Sik
    • Journal of Photoscience
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    • v.10 no.3
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    • pp.237-240
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    • 2003
  • The tetradecameric peptide (K47-K60) near the NH$_2$-terminal region of epithelial-cell adhesion molecule (Ep-CAM) was chosen as antigenic site and a polyclonal antibody was generated, which could recognize Ep-CAM from the mouse colon tissue or the colon cancer cell, CT-26, in Western blot analysis. Then, the fluorescein isothiocyanate (FITC), a fluorescence dye, was conjugated with the affinity purified Ep-CAM antibody using thiocyanate and the amino groups of FITC and antibody, respectively. The molar ratio of FITC to antibody was estimated approximately 1.86 to 1.00 by measuring the optical densities at 492 nm and 280 nm. Ep-CAM antibody-FITC conjugate was then used for immunohistochemistry of the CT-26 cells. Judging from the shapes formed by fluorescence, the Ep-CAM antibody could delivered FITC to the surface of cells in which Ep-CAM was expressed. This result implies that Ep-CAM antibody could be also used for the tissue-specific delivery of the photosensitizer to the target protein via antigen-antibody interaction.

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An Active Fraction on Phagocytosis of Murine Peritoneal Macrophage in Lithospermi Radix (자근에 함유된 복강 마크로파지의 탐식능 활성분획)

  • Jeon, Hoon;So, June-No;Eun, Jae-Soon
    • Korean Journal of Pharmacognosy
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    • v.29 no.4
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    • pp.391-395
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    • 1998
  • The phagocytic activity of murine peritoneal macrophages was determined by lucigenin chemiluminescence with luminometer and engulfment of fluorescein-conjugated E. coli particles. 70% MeOH extract of Lithospermi Radix was fractionated successively with hexane, methylene chloride, n-BuOH and water. The water fraction (m.w. 500 to 1,000) enhanced the lucigenin chemiluminescence and the engulfment of fluorescein-conjugated E. coli particles in murine peritoneal macrophages. The water fraction suppressed the production of nitric oxide in the macrophages. These results suggest that an active fraction of phagocytosis in Lithos-permi Radix is the water fraction and the molecular weight is 500 to 1,000.

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Correction of Ocular Fundus Fluorescein Angiogram in Nonlinear Distortion (비선형왜곡된 형광안저화상의 보정)

  • 고창림
    • Journal of Biomedical Engineering Research
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    • v.11 no.1
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    • pp.31-38
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    • 1990
  • Image correction of the fluorescein angiogram with the low contrast and geometrically distorted is studied. The procedure is divided into two steps : A template matching step and a geometrical transformation step. Based on the sequential similiarity detection algorithm, more Improved matching results are obtained with edge enhanced image. For the reference points and the corresponding matchimg points, the geometrical transformationss by the use of the average value of the X, Y translational shifts and a pair of these points, respectively are described. Then the corrected images are obtained using bilinear interpolation. It is proven that the usefullness of this study for the image correction of the ocular fundus fluoresceln angiogram with low contrast and geometrically distorted mainly due to the eye movements.

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Dye Leakage Measurement in Time Series Flucrescein Ocular Fundus Photographs (시계열 형광안저오진에서의 조경제 루출량 측정)

  • Kwon, Kap-Hyeon;Ha, Yeong-Ho;Kim, Soo-Joong
    • Journal of Biomedical Engineering Research
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    • v.12 no.4
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    • pp.295-302
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    • 1991
  • In this paper, the inter- and intra-frame distortions in the gray levels of a series of fluorescein ocular fundus photographs are corrected. For doing this, the background images are extracted from original images using the image blurring effect by decimation, and then shading corrected images are obtained by subtracting the background images from the original images pixel by pixel. In a series of fluorescein ocular fundus photographs, after the gray scale distoriton is corrected, the intensity volumes of dye leakage are measured and represented by a graph. These data may be useful for the prediction of prognosis and the therapeutic management.

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A Suppressive Component on Phagocytosis of Murine Peritoneal Macrophage in Aurantii immaturi pericarpium (청피에 함유된 복강 마크로파지의 탐식작용 억제 성분)

  • Eun, Jae-Soon;Kim, Dae-Keun;So, June-No;Zee, Ok-Pyo
    • YAKHAK HOEJI
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    • v.42 no.6
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    • pp.567-571
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    • 1998
  • The phagocytic activity of murine peritoneal macrophage, was determined by lucigenin chemiluminescence and engulfment of fluorescein-conjugated E. coli particle. The acti vity-guided fractionation upon the methylenechloride fraction of Aurantii immaturi pericarpium led to the isolation of a flavonoid, isosinensetin, as a suppressive component of phagocytosis. Isosinensetin suppressed the lucigenin chemiluminescence and the engulfment of fluorescein-conjugated E. coli particles and enhanced the production of nitric oxide in murine peritoneal macrophage.

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Systematic Study of Fluorescein-Functionalized Macrophotoinitiators for Colorimetric Bioassays

  • Lee, Jeong-Gyu;Han, Gyeong-Yeop;Go, Sang-Won;Sikes, Hadley D.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.263.2-263.2
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    • 2013
  • We report a systematic investigation of a set of macrophotoinitiators for use in polymerization-based signal amplification. To test the dependence of photopolymerization responses on the number of photoinitiators localized per molecular recognition event, we gradually increased the number of photoinitiator molecules coupled to a scaffold macromolecule. Macrophotoinitiators constructed with an average of 7 to 168 photoinitiators per polymer with the goals of quantifying the relationship between the number of initiators per binding event and the degree of amplified colorimetric readout. To evaluate the capacity of the macrophotoinitiators to detect molecular recognition, neutravidin was coupled to these molecules to recognize biotin-labeled DNA immobilized on biochip test surfaces. Fluorescein macroinitiators are found to be useful in detecting molecular recognition above a threshold of initiators per polymer. Above this threshold, increasing the number of initiators per macroinitiator resulted in increased signal strength.

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Effects of Food Components on the Antibacterial Activity of Chitosan against Escherichia coli

  • Hong, Yi Fan;Moon, Eun-Pyo;Park, Yun-Hee
    • Food Science and Biotechnology
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    • v.17 no.6
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    • pp.1365-1367
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    • 2008
  • The antibacterial activity of chitosan against Escherichia coli was investigated in the presence of NaCl, sucrose, and ethanol to assess the potential use of chitosan as a biopreservative in food products containing these components. The inhibitory activity of chitosan decreased slightly upon the addition of NaCl and sucrose, respectively to culture broth containing 100 ppm of chitosan (Mw 3,000), while the addition of ethanol enhanced the inhibitory activity of chitosan on growing cells. The addition of these components to non-growing cells prior to chitosan treatment demonstrated that NaCl protected the cells from the inhibitory activity of chitosan, while sucrose had no effect. Ethanol addition to non-growing cells increased cell death by chitosan treatment. Finally, binding of fluorescein isothiocyanate (FITC)-labeled chitosan to E. coli was measured in the presence of the food components. The FITC-labeled chitosan binding to cells decreased upon NaCl addition, was not affected by sucrose, and increased following treatment with ethanol.

Photo-controlled gene expression by fluorescein-labeled antisense oligonucleotides in combination with visible light irradiation

  • Ito, Atsushi;Kaneko, Tadashi;Miyamoto, Yuka;Ishii, Keiichiro;Fujita, Hitoshi;Hayashi, Tomonori;Sasaki, Masako
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.451-453
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    • 2002
  • A new concept of "photo" -antisense method has been evaluated, where the inhibition of gene expression by the conventional antisense method is enhanced by photochemical binding between antisense oligonucleotides conjugated with photo-reactive compound and target mRNA or DNA. Fluorescein labeled oligodeoxyribonucleotides (F-DNA) was delivered to cell nuclei in the encapsulated form in multilamellar lecithin liposomes with neutral charge. F-DNA was previously shown to photo-bind to the complementary stranded DNA, and the delivery system using neutral liposome to be effective in normal human keratinocytes. In the present study, we used human kidney cancer G401.2/6TG.1 cell line to be advantageous in reproducible experiments. p53 was adopted as a target gene since antisense sequence information has been accumulated. The nuclear localization ofF-DNA was identified by comparing the fluorescence ofF-DNA with that of Hoechst 33258 under fluorescence microscope. After 7hr incubation to accumulate p53 protein induced by UV -B, p53 protein was quantified by Western blot. After 2hrs from F-DNA application, about 30% of cell population incorporated F-DNA in their nuclei with some morphological change possibly due to liposomal toxicity. Irradiation of visible light longer than 400nm from solar simulator at this time enhanced the inhibitory action of antisense F-DNA. The present results suggest that photo-antisense method is promising to control gene expression in time and space dependent manner. Further improvement of F-DNA delivery to cancer cells in the stability and toxicity is in progress. progress.

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A Simple Strategy in Avulsion Flap Injury: Prediction of Flap Viability Using Wood's Lamp Illumination and Resurfacing with a Full-thickness Skin Graft

  • Lim, Hyoseob;Han, Dae Hee;Lee, Il Jae;Park, Myong Chul
    • Archives of Plastic Surgery
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    • v.41 no.2
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    • pp.126-132
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    • 2014
  • Background Extensive degloving injuries of the extremities usually result in necrosis of the flap, necessitating comprehensive skin grafting. Provided there is a sufficient tool to evaluate flap viability, full-thickness skin can be used from a nonviable avulsed flap. We used a Wood's lamp to determine the viability of avulsed flaps in the operation field after intravenous injection of fluorescein dye. Methods We experienced 13 cases during 16 months. Fifteen minutes after the intravenous injection of fluorescein dye, the avulsed skin flaps were examined and non-fluorescent areas were marked under Wood's lamp illumination. The marked area was defatted for full-thickness skin grafting. The fluorescent areas were sutured directly without tension. The non-fluorescent areas were covered by defatted skin. Several days later, there was soft tissue necrosis within the flap area. We measured necrotic area and revised the flap. Results Among all the cases, necrotic area was 21.3% of the total avulsed area. However, if we exclude three cases, one of a carelessly managed patient and two cases of the flaps were inappropriately applied, good results were obtained, with a necrotic area of only 8.4%. Eight patients needed split-thickness skin grafts, and heel pad reconstruction was performed with free flap. Conclusions A full-thickness skin graft from an avulsed flap is a good method for addressing aesthetic concerns without producing donor site morbidity. Fluorescein dye is a useful, simple, and cost-effective tool for evaluating flap viability. Avulsed flap injuries can be managed well with Wood's lamp illumination and a full-thickness skin graft.