• Title/Summary/Keyword: OCT

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OCT Image Enhancement using spectral filtering with Erbium-doped Fiber as an Absorber (EDF spectral filtering을 이용한 OCT 영상 개선)

  • 나지훈;최은서;이병하;이창수
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.07a
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    • pp.254-255
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    • 2003
  • OCT (Optical Coherence Tomography)는 여러 단층영상 촬영기법의 하나로써 절개 없이도 생체의 복잡한 내부구조를 고분해능으로 이미징할 수 있는 장점을 갖고 있다. 고분해능 OCT 이미지는 사용되는 광원에 의해서 결정되는데 가우시안 형태를 갖는 넓은 파장대역의 광원일수록 높은 분해능이 가능하게 된다. OCT에서 사용되는 광원의 종류는 SLD, EELED, ASE등이 사용되고 있다. 그 중에서 ASE광원은 높은 출력 파워를 갖고 넓은 파장대역을 포함하지만 스펙트럼의 형태가 가우시안이 아닌 단점을 가지고 있다. (중략)

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2-D OCT image implementation using low coherence SLD (Low coherence 특성의 SLD를 이용한 2차원 OCT 영상 구현)

  • 정태호;박양하;오상기;김용평
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.02a
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    • pp.290-291
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    • 2003
  • Optical Coherence Tomography is a new medical dianostic imaging technology which can perform micron resolution cross-sectional or tomograpic imaging in biological tissue. In this paper, we analyze OCT system. And we have 2-dimensional OCT image implementation using low coherence SLD.

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Alteration of DNA Methylation in Oct-4 Gene in Mouse Preimplantation Embryos by the Interference RNA

  • Kim, Jong-Mu;Ko, Yeoung-Gyu;Seong, Hwan-Hoo;Chung, Hak-Jae;Chang, Won-Kyong;Kim, Nam-Hyung
    • Reproductive and Developmental Biology
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    • v.31 no.1
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    • pp.21-28
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    • 2007
  • During early embryo development, Oct-4 is an important transcription factor for the early differentiation the present study was first examined methylation status in distal enhancer and promoter region of Oct-4 during mouse pre-implantation embryo development. In oocyte and sperm, high methylation was observed in both distal and proximal of promoter in Oct-4. Following fertilization relatively high methylation level remained until 8-cell stage embryos, but decreased at the morula and blastocyst stage. Specific gene knock down of Oct-4 by siRNA injection into zygote induced higher methylation rates of both distal and proximal region of promoter of Oct-4. These results suggest a functional link between the DNA methylation status of distal and promoter resign in the Oct-4 gene and the gene sequence-specific transcriptional silencing by exogenous siRNA injection during mouse preimplantation embryos.

A Study on the Improvement of Resolution of Optical Coherence Tomography System Using Femto-Second Laser (펨토초 레이저를 이용한 OCT 시스템의 분해능 향상에 관한 연구)

  • Yang, Sung-Kuk;Park, Yang-Ha;Chang, Won-Suk;Oh, Sang-Ki;Kim, Hyun-Duk
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.18 no.6
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    • pp.31-36
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    • 2004
  • Optical coherence tomography system has been extensively studied because it has some advantages such as imaging of high resolution, low cost, and compact size configuration. In order to obtain high resolution of OCT system we configured OCT system using a femto-second laser. We measure the pulse width using autocorrelator function because a femto-second laser is ultra short pulse. And we measured the practical resolution using theoretical equation and the measurement of reference sample. It is confirmed that the proposed OCT system has 1.5 times higher resolution and un distinctive cross-sectional image than OCT system with SLD as a light source.

3-D OCT Image Reconstruction for Precision Analysis of Rat Eye and Human Molar (쥐 눈과 인간 치아의 정밀한 단층정보 분석을 위한 OCT 3-D 영상 재구성)

  • Jeon, Ji-Hye;Na, Ji-Hoon;Yang, Yoon-Gi;Lee, Byeong-Ha;Lee, Chang-Su
    • The KIPS Transactions:PartB
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    • v.14B no.6
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    • pp.423-430
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    • 2007
  • Optical coherence tomography(OCT) is a high resolution imaging system which can image the cross section of microscopic organs in a living tissue with about $1{\mu}m$ resolution. In this paper, we implement OCT system and acquire 2-D images of rat eye and human molar samples especially in the field of opthalmology and dentistry. In terms of 2-D images, we reconstruct 3-D OCT images which give us another inner structural information of target objects. OPEN-GL reduces the 3-D processing time 10 times less than MATLAB.

Effect of dietary octacosanol concentration extracted from triticale sprout on laying performance, egg quality, and blood parameters of laying hens

  • Chun Ik, Lim;Kyeong Seon, Ryu
    • Journal of Animal Science and Technology
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    • v.64 no.5
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    • pp.863-870
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    • 2022
  • This study was conducted to investigate the effect of dietary supplementation of octacosanol (OCT) extracted from triticale sprout on laying performance, egg quality, and blood parameters of laying hens. A total of 192, Hyline brown laying hens aged 43 weeks were divided into 4 dietary groups of 48 birds each and they were randomly subjected to one of the experimental diets containing OCT at the levels of none, 10, 20, and 30 mg/kg of diet. All birds were fed with isoenergetic and isonitrogenous mash diets for 6 weeks. The result showed that hens supplemented with 20 and 30 mg/kg OCT in diet significantly increased (p < 0.05) egg production than those fed with the basal diet. OCT concentration in the egg yolk of hens fed with 20 and 30 mg/kg OCT was significantly higher than in those fed the control diet. Hens fed 20 and 30 mg/kg OCT exhibited greater high-density lipoprotein (HDL) cholesterol and interleukin (IL) concentrations and reduced serum concentrations of cholesterol and triglyceride compared to those fed with 0 and 10 mg/kg OCT. This study indicates that supplementing the diet of laying hens with 20 and 30 mg/kg of OCT can improve the performance, egg quality, and health status of laying hens.

Haplotype Analysis and Single Nucleotide Polymorphism Frequency of Organic Cation Transporter Gene (OCT1 and 2) in Korean Subjects

  • Kim, Se-Mi;Lee, Sang-No;Yoon, Hwa;Kang, Hyun-Ah;Cho, Hea-Young;Lee, Il-Kwon;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.39 no.5
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    • pp.345-351
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    • 2009
  • Organic cation transporters (OCTs) are important for absorption, elimination of many endogenous small organic cations as well as a wide array of drugs and environmental toxins. This gene is located in a cluster on chromosome 6 and OCTs are in major organs such as intestine, liver, kidney, brain and placenta. Therefore, expression levels and function of OCTs directly affect plasma levels and intracellular concentrations of drugs and thereby determine therapeutic response. The aim of this study was to investigate the frequency of the SNPs on OCT1 (C181T and C1022T) and OCT2 (G808T) to analyze haplotype frequency in healthy Korean population. Human subjects have been genotyped for OCT1 (C181T for 195 subjects and C1022T for 825 subjects), using polymerase chain reaction-based diagnostic tests (RFLP). And for OCT2 (G808T), a total of 861 subjects have been genotyped, using pyrosequencing method. Haplotype was statistically inferred using an algorithm based on the expectation-maximization (EM). OCT1 C181T genotyping showed 100% homozygous wild-type (C/C). OCT1 C1022T genotyping showed wild-type (C/C), heterozygous (C/T) and homozygous mutant-type (T/T) and each accounted for 72.1, 24.5 and 3.4%, respectively. OCT2 G808T genotyping results also showed homozygous wild-type (G/G), heterozygous (G/T) and homozygous mutant-type (T/T) and each took 81.8, 17.9 and 0.3%, respectively. Based on these genotype data, haplotype analysis between OCT1 C181T and OCT1 C1022T has proceeded. The result has revealed that linkage disequilibrium between alleles is not obvious (P=0.0122).