• Title/Summary/Keyword: aberrations

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Analysis of Corneal Higher-order Aberrations after Myopic Refractive Surgery

  • Kim, Jeong-mee
    • Current Optics and Photonics
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    • v.3 no.1
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    • pp.72-77
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    • 2019
  • This study was performed to analyze the optical aberrations of the cornea induced by myopic refractive surgery. Corneal total higher-order aberrations, spherical aberration and coma for 4-mm and 6-mm pupils were measured using a wave-front analyzer. The amount of aberrations of the oblate corneal optics by the achieved correction was found to be larger than for the prolate corneal shape with complete eye, in an emmetropia control group. The change in corneal shape acts as an optical factor that degrades the quality of the retinal image; it seems to be one of the important factors related to quality of vision.

Suppressing Effects of Tannic Acid on UVB induced Chromosome Aberrations in Chinese Hamster Lung Cells (자외선(UVB)에 의한 염색체이상과 Tannic acid의 방어효과)

  • 김정현;맹승희;임철홍;안령미
    • Environmental Mutagens and Carcinogens
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    • v.17 no.1
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    • pp.17-22
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    • 1997
  • We observed the frequency of chromosome aberrations induced by UVB irradiations, and the suppressing effect of tannic acid on chromosome aberrations induced by UVB irradiations in CHL cells, which is a phenolic compound, a hydrolysate of tannin and a components of green tea. UVB doses used for the frequency of chromosome aberrations were from 0.2 to 1.6 KJ/m$^2$ and tannic acid concentrations were from 1.16 $\mu$g/ml to 37.50 $\mu$g/ml. For the observation of suppressing effect of tannic acid on UVB-induced chromosome aberrations, UVB dose was 1.6 KJ/m$^2$ and tannic acid concentrations were 1.0, 2.0, 4.0 $\mu$g/ml. In our study, tannic acid was treated for 24 hours in CHL, cells after UVB irradiation without S9 mix or for 6 hours with S9 mix. From this study, we obtained the following results : (1) The frequency of chromosome aberrations UVB induced were dose-dependently increased. (2) The tannic acid did not induce chromosome aberrations in cultured Chinese hamster cells. (3) UVB-induced chromosome aberrations were suppressed by tannic acid at every concentration from 1.0 $\mu$g/ml to 4.0 $\mu$g/ml with or without metabolic activation. These results suggest that the tannic acid acts as an inhibitor to UVB-induced clastogenicity of the cultured cell.

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Effect of 3-Aminobenzamide on DNA Repair Synthesis and Chromosome Aberrations Induced by Mutagens in Synchronized Mammalian Cells (동시화된 포유동물세포에서 돌연변이원에 의해 유발된 DNA 회복합성 및 염색체이상에 미치는 3-Aminobenzamide의 영향)

  • 신은주;강인영;엄경일
    • Environmental Mutagens and Carcinogens
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    • v.11 no.2
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    • pp.107-117
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    • 1991
  • The effect of 3-aminobenzamide (3AB), an inhibitor of poly (ADP-ribose) polymerase, on ethyl methanesulfonate (EMS)-or bleomycin (BLM)-induced DNA repair synthesis and chromosome aberrations was examined during the cell cycle of Chinese hamster ovary (CHO)-K$_1$ cells. The synchronized cells were obtained by using thymidine double block method and mitotic selection method. Three assays were employed in this study: unscheduled DNA synthesis, alkaline elution and chromosome aberrations. 3AB alone did not induce DNA repair and chromosome aberrations in all phases. The post-treatment with 3AB inhibited DNA repair synthesis induced by EMS or BLM in G$_2$ phase, whereas 3AB did not affect chromosome aberrations induced by EMS or BLM in all phases. These results suggest that 3AB aggravates the cell cycle disturbance which occur after DNA damage, and leads to an accumulation of cells at G$_2$ phase, and inhibits DNA repair synthesis, while the effect 3AB on chromosome aberrations may need reevaluated.

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Quantifying Aberrations on Object Plane Using Zernike Polynomials

  • Yohan Kim;Theo Nam Sohn;Cheong Soo Seo;Jin Young Sohn
    • Current Optics and Photonics
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    • v.8 no.2
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    • pp.151-155
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    • 2024
  • Optical systems often suffer from optical aberrations caused by imperfect hardware, which places significant constraints on their utility and performance. To reduce these undesirable effects, a comprehensive understanding of the aberrations inherent to optical systems is needed. This article presents an effective method for aberration detection using Zernike polynomials. The process involves scanning the object plane to identify the optimal focus and subsequently fitting the acquired focus data to Zernike polynomials. This fitting procedure facilitates the analysis of various aberrations in the optical system.

Assessment of Chromosomal Analyses of 1,180 Cases Suspected of Chromosomal Aberrations (염색체이상을 의심한 1,180례의 염색체 분석 결과 검토)

  • Jeong, Hyeon Kyoung;Ahn, Eun Young;Rim, Sung Soo;Kim, Eun Young;Kim, Kyoung Sim;Kim, Yong Wook;Kim, Ki Bok
    • Clinical and Experimental Pediatrics
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    • v.45 no.3
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    • pp.311-319
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    • 2002
  • Purpose : We have performed this study to obtain reference data for the distribution of chromosomal aberrations in Korea. Methods : We analyzed 1,180 chromosomal study cases from Kwang ju Christian Hospital during the past 25 years. 756 cases suspected of characteristic chromosomal aberration syndromes and 424 cases with hermaphroditism, mild sexual abnormalities, multiple anomalies, or mental & growth retardation were included. Results : The male to female ratio of autosomal aberration syndromes was 1.2 : 1. 78.6% of autosomal aberrations were diagnosed under 1 year of age, whereas 89.8% of sex chromosomal aberrations were diagnosed over 12 years of age. Among 1,180 cases, 612 ones had chromosomal aberrations(51.9%) : 590 of 756 cases suspected of chromosomal aberration syndromes had aberrations( 78.0%), whereas 22 of 424 showing the above other features had aberrations(5.2%). Autosomal aberrations appeared in 514 cases(83.8%) and sex chromosomal aberrations appeared in 98 cases(16.2%). The most frequently observed abberation in autosomal aberrations was Down syndrome, followed by E, D, B, A and C group aberrations. The most common abberation in sex chromosomal aberrations was Turner syndrome, followed by Klinefelter syndrome and Fragile X syndrome. Conclusion : It is of vital importance that patients suspected of chromosomal aberrations undergo chromosomal analysis. Further advanced chromosomal staining and molecular genetic methods will raise the detection rate of chromosomal aberrations.

The Effect of Myopic Degree on the Change of Higher-order Aberrations Induced by Aging (근시도가 나이에 따라 유발되는 고위수차의 변화에 미치는 영향)

  • Ryu, Nam-Yul;Park, Kyoung-Hee;Kim, So-Ra;Park, Mi-Jung
    • Journal of Korean Ophthalmic Optics Society
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    • v.19 no.3
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    • pp.353-362
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    • 2014
  • Purpose: The present study was aimed to investigate the change of higher-order aberrations induced by aging and the effect of myopic degree on the correlation between age and higher-order aberrations. Methods: The higher-order aberrations in 931 eyes aged from 20 to 60 were measured by using a LADARWave device employing Hartmann-Shack system to analyze the effect of myopic degree measured by manifest refraction test on higher-order aberrations. Results: Coma and vertical coma aberrations were significantly decreased by the increase of myopic degree while vertical astigmatic aberration was significantly increased. The correlations of age and coma, vertical coma, spherical, vertical trefoil, horizontal trefoil, vertical astigmatic, horizontal astigmatic and vertical tetrafoil aberrations depended on the myopic degree, except for horizontal coma and horizontal tetrafoil aberrations. Conclusions: It is suggested to consider the myopic degree for the refractive correction including the laser surgery based on the present result that higher-order aberrations are affected by the myopic degree.

Genome-wide Examination of Chromosomal Aberrations in Neuroblastoma SH-SY5Y Cells by Array-based Comparative Genomic Hybridization

  • Do, Jin Hwan;Kim, In Su;Park, Tae-Kyu;Choi, Dong-Kug
    • Molecules and Cells
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    • v.24 no.1
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    • pp.105-112
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    • 2007
  • Most neuroblastoma cells have chromosomal aberrations such as gains, losses, amplifications and deletions of DNA. Conventional approaches like fluorescence in situ hybridization (FISH) or metaphase comparative genomic hybridization (CGH) can detect chromosomal aberrations, but their resolution is low. In this study we used array-based comparative genomic hybridization to identify the chromosomal aberrations in human neuroblastoma SH-SY5Y cells. The DNA microarray consisting of 4000 bacterial artificial chromosome (BAC) clones was able to detect chromosomal regions with aberrations. The SH-SY5Y cells showed chromosomal gains in 1q12~ q44 (Chr1:142188905-246084832), 7 (over the whole chro-mosome), 2p25.3~p16.3 (Chr2:18179-47899074), and 17q 21.32~q25.3 (Chr17:42153031-78607159), while chromosomal losses detected were the distal deletion of 1p36.33 (Chr1:552910-563807), 14q21.1~q21.3 (Chr14:37666271-47282550), and 22q13.1~q13.2 (Chr22:36885764-4190 7123). Except for the gain in 17q21 and the loss in 1p36, the other regions of gain or loss in SH-SY5Y cells were newly identified.

The Possible Protective Role of Korean Ginseng on Ochratoxicosis: with Special References on Chromosomal Aberrations in Rats.

  • Nada, Spomaia A.;Arbid, Mahmoud S.;Ramadan, A.I.
    • Proceedings of the Ginseng society Conference
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    • 1998.06a
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    • pp.253-262
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    • 1998
  • Ochratoxin A (OA) is a potent mycotoxin causing considerable health hazard and economic loss- e,i. OA is of concern as it is hepato-nephrotoxic, mutagenic, and carcinogenic to a great variety of animals. LDso of crude OA was 8.5 mgf kg.b.w., i.p. The clinical symptoms, mortalities and necropsy were recorded in rats injected with OA (LD5o, i.p.) during 10 days of daily treatment. Ginseng treatments (20 mg 1 kg. b.w., i.p.) : before, mixed with, or after OA dose, completely prevented the mortality in rats. OA-treated animals showed microcytic normochromic anaemia, lucocytosis, hypoproteinaemia and elevation of serum ALT, AST, AP, urea, and creatinine values. These findings were declined near the normal levels when ginseng injected with OA. OA (115 LDso) induced chromosomal aberrations (65.66%) compared to the control. When ginseng given 10 min before OA injection, chromosomal aberrations were reduced to be 31.66% compared to OA-treated animals. In conclusion: ginseng has a protective effect against ochratoxicosis, it has anti-genotoxic activity and it can repair the chromosomal damage induced by ochratoxin A. Key words Ochratoxicosis, Chromosomal aberrations, Mycotoxins, Ochratoxin A, Korean gin sting, Protective effect of Panax ginseng, Rat

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After Lasek Surgeried and TransPRK Surgeried for Myopia, Comparison of High-order Aberrations (근시에서의 라섹과 TransPRK라섹 수술 후 고위수차 비교)

  • Park, Jun-Sung
    • Journal of Korean Clinical Health Science
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    • v.3 no.2
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    • pp.372-377
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    • 2015
  • Purpose: The aim of this study is to compare total high order aberrations between surgery which uses TransPRK and general laser assisted sub-epithelial keratomileusis. Methods: The patients who had general laser assisted sub-epithelial and TransPRK laser assisted sub-epithelial by visiting ophthalmic clinic in Ulsan from January 2014 to August 2014 was researched. Results: When comparing total high order aberrations before and after operation, it was found that total high order aberration in general laser assisted sub-epithelial group increased to $0.222{\pm}0.078{\mu}m$ from $0.074{\pm}0.019{\mu}m$ while that in TransPRK assisted sub-epithelial group increased to $0.179{\pm}0.045{\mu}m$ from $0.076{\pm}0.032{\mu}m$. When comparing the increment in total high order aberrations between two groups after surgery, it was found that the increments of TransPRK assisted sub-epithelial group were statistically smaller than that of general laser assisted sub-epithelial group (p<0.05). Conclusions: This study made a comparative analysis of total high order aberrations between general laser assisted sub-epithelial and TransPRK assisted sub-epithelial which was introduced recently and the result showed a significant difference. The findings of this study suggest that TransPRK assisted sub-epithelial can be used widely in simply improving eye sight and quality of vision by reducing an increase in high order aberration caused by orthokeratology surgery. It is expected that TransPRK assisted sub-epithelial will be helpful for improving the understanding quality of eye sight which occurs by several methods of vision correction surgery.

Measurement of Wavefront Aberrations in Off-Axis Parabolic Mirrors and its Dependence on the Misalignment (레이저 빔의 파면 측정을 통한 비축 포물 거울의 성능 평가 및 정렬 오차 민감도에 관한 연구)

  • Jeong, Tae-Moon;Choi, Il-Woo;Ko, Do-Kyeong;Lee, Jong-Min
    • Korean Journal of Optics and Photonics
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    • v.17 no.3
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    • pp.256-261
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    • 2006
  • Wavefront aberrations of a laser beam that was reflected from an off-axis parabolic (OAP) mirror were measured to evaluate the optical performance of the OAP mirror. For a diamond turned OAP mirror, the root-mean-square (rms) value of higher-order aberrations was only $0.03{\mu}m$ for the laser beam size of about 34 mm. The other OAP mirror which was polished at a domestic company had the rms value of higher-order aberrations of $2.07{\mu}m$ for the same beam size. Although the diamond turned OAP mirror was well fabricated to have a small amount of aberrations, the aberrations were induced by the misalignment of the OAP mirror. Especially, 0 degree astigmatism increased with the sensitivity of $0.372{\mu}m/mrad$ when the OAP mirror was tilted in the tangential plane, which agreed well with the calculated results using a commercial ray tracing software.