• Title/Summary/Keyword: Dose-response

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Fingernail electron paramagnetic resonance dosimetry protocol for localized hand exposure accident

  • Jae Seok Kim;Byeong Ryong Park;Minsu Cho;Won Il Jang;Yong Kyun Kim
    • Nuclear Engineering and Technology
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    • v.55 no.1
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    • pp.270-277
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    • 2023
  • Exposure to ionizing radiation induces free radicals in human nails. These free radicals generate a radiation-induced signal (RIS) in electron paramagnetic resonance (EPR) spectroscopy. Compared with the RIS of tooth enamel samples, that in human nails is more affected by moisture and heat, but has the advantages of being sensitive to radiation and easy to collect. The fingernail as a biological sample is applicable in retrospective dosimetry in cases of localized hand exposure accidents. In this study, the dosimetric characteristics of fingernails were analyzed in fingernail clippings collected from Korean donors. The dose response, fading of radiation-induced and mechanically induced signals, treatment method for evaluation of background signal, minimum detectable dose, and minimum detectable mass were investigated to propose a fingernail-EPR dosimetry protocol. In addition, to validate the practicality of the protocol, blind and field experiments were performed in the laboratory and a non-destructive testing facility. The relative biases in the dose assessment result of the blind and field experiments were 8.43% and 21.68% on average between the reference and reconstructed doses. The results of this study suggest that fingernail-EPR dosimetry can be a useful method for the application of retrospective dosimetry in cases of radiological accidents.

Medical Preparedness in Radiation Accidents (방사선 사고시의 의료대책)

  • Kim, Eun-Sil;Kim, Jong-Soon
    • Journal of Radiation Protection and Research
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    • v.21 no.3
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    • pp.201-215
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    • 1996
  • Radiation and radioactive materials serve man in many beneficial ways. Diagnostic X-ray, radiation therapy, and other nuclear medicine uses of radioactivity save thousands of lives each year. Industrial application of radiation, such as radiography, make many manufactured products more reliable and less expensive. Nuclear power plants are producing more electrical power each year and reducing our dependence on imported oil. However, radiation can and dose produce harmful effects particularly as the reault of a radiation accident in which a victim receives as the result of a radiation accident in which a victim receives a large dose. Fortunately such accidents are very rare and recently we need more electric power produced by nuclear power plants. Considering increase of use of radiation or radioactive materials, we have to establish the radiological emergency response system prepared for radiation accidents.

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The Effect of Ginseng Petroleum Ether Fraction on Immunosuppressed Mice by Lead acetate (II) II. Cellular Immune Response and Histological Studies (납의 면역독성에 미치는 인삼의 영향(II) II. 세포성면역 및 조직학적 검사)

  • 김휘배;안영근;김주영;문재규
    • Environmental Analysis Health and Toxicology
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    • v.1 no.1
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    • pp.37-46
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    • 1986
  • Experiments were performed to investigate the effect of Panax ginseng petroleum ether fraction on delayed type hypersensitivity, rosette formation, phagocytic activity and histophathological influence in lead acetate treated mice. Lead acetate was administered in the drinking water and ginseng pet. ether fraction was injected i.p.. Mice were sensitized and challenged with sheep red blood cells. Erythrocyte(I) rosette formation and DTH reaction were significantly depressed in lead acetate treated mice, and those were restored administration of ginseng fraction. Ginseng pet. ether fraction administration did not have any effect on decreased phagocytic activity. Follicular and parafollicular areal destruction of spleen, and destruction of thymus were finded in lead acetate exposed-mice. Small dose of ginseng pet. ether fraction (5 mg/kg, 10 mg/kg), administraction inhibited those histopathological changes, but large dose (20 mg/kg) didn't.

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Application of Single Cell Gel Electrophoresis for Detection of DNA Single Strand Breaks in DNA of Fish Blood Cell (어류혈구세포에 있어서 Single Cell Gel Electrophoresis를 응용한 DNA Single Strand Breack의 측정)

  • KIM Gi Beum;LEE Richard F.;MARUYA Keith A.
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.4
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    • pp.346-351
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    • 2003
  • Single-cell gel electrophoresis (comet assay) was used to detect DNA single strand break in blood cells from several marine fish species. Three fish species were collected from Georgia coastal area. Mummichog, Fundulus heteroclitus showed higher DNA damage than sea bass, Lateolabrax japonicus and trout, Oncorhynchus masou masou under the same experimental conditions. Mummichogs had more alkaline-labile sites on their DNA than other fish species. The comet assay with mummichog blood cells at pH 12.5 showed a dose-response curve with the increasing concentrations of hydrogen peroxide. While the isolated leucocytes showed no increase of DNA damage after in vitro exposure to 2-methyl-1,4-naphthoquinone (MNQ), erythrocytes showed dose-dependent DNA damage. These results indicate that the comet assay can be applied successfully as a bioassay using erythrocyte for environmental monitoring.

Development of a One-step Two-site Enzyme Immunoassay for Measuring Human Alpha-fetoprotein by Eliminating Hook-effect

  • Kim, Se-Ho
    • BMB Reports
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    • v.34 no.1
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    • pp.47-50
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    • 2001
  • A one-step, two-site enzyme immunoassay was developed for measuring human alpha-fetoprotein (AFP) in serum and amniotic fluid using monoclonal antibodies (McAb) by eliminating the high-dose hook effect. Three McAbs that recognize different epitopes were selected among 16 different clones on the basis of epitope mapping, two for immobilization and one for horseradish peroxidase conjugation. This one-step immunoassay system is more convenient and rapid compared to a conventional two-step sandwich immunoassay system. It did not exhibit the hook effect to around 2.7 mg/ml of AFP, which is probably one of the highest concentrations of AFP in the serum. The dose-response curve of the system was linear to 500 mg/ml of AFP and the system could differentiate as low as 1 mg/ml of AFP The intra- and inter-assay variations were in an acceptable range; 95~104% and 97~105% respectively Its correlation with other commercial systems was around 95%.

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Effects of Ionizing Radiation on Plants and the Radiological Protection of the Environment

  • Stanislav A. Geras'kin;Kim, Jin-Kyu
    • Korean Journal of Environmental Biology
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    • v.21 no.4
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    • pp.321-327
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    • 2003
  • Differences between the principles for the radiological protection of man and the environment are compared. The derived levels of exposure for man and biota recommended by the international agencies with dose rates for chronic radiation producing effects at different levels of biological organization were given in terms of the biological effects. Cytogenetic effects on plants after an exposure to ionizing radiation at low doses alone and in combination with other factors are discussed. A wide range of experimental data were analysed and the general conclusions were extracted to cover the topics such as non-linearity of dose response, synergistic and antagonistic effects of the combined exposure of different factors, radiation-induced genomic instability, and the phenomena of radioadaptation.

Treatment of Drug Susceptible Pulmonary Tuberculosis

  • Shin, Hong-Joon;Kwon, Yong-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.78 no.3
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    • pp.161-167
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    • 2015
  • Tuberculosis (TB) remains a major global health problem, and the incidence of TB cases has not significantly decreased over the past decade in Korea. The standard short course regimen is highly effective against TB, but requires multiple TB-specific drugs and a long treatment duration. Recent studies using late-generation fluoroquinolones and/or high-dose rifapentine-containing regimens to shorten the duration of TB treatment showed negative results. Extending the treatment duration may be considered in patients with cavitation on the initial chest radiograph and positivity in sputum culture at 2 months of treatment for preventing TB relapse. Current evidence does not support the use of fixed-dose combinations compared to separate drugs for the purpose of improving treatment outcomes. All patients receiving TB treatment should be monitored regularly for response to therapy, facilitation of treatment completion, and management of adverse drug reactions. Mild adverse effects can be managed with symptomatic therapy and changing the timing of the drug administration, but severe adverse effects require a discontinuation of the offending drugs.

Chromosome Aberration and Sister Chromatid Exchange for the Assessment of Cadmium Toxicity (카드뮴독성을 평가하기 위한 방법으로서의 염색체 이상 및 자매염색체 교환)

  • 맹승희;정해원
    • Journal of Environmental Health Sciences
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    • v.17 no.1
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    • pp.110-119
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    • 1991
  • This study was performed to investigate the applicability of 9 chromosome aberration and sister chromatid exchange analysis for the assessment of cytotoxicity and cytogenetic effects of cadmium. Induction of chromosome aberration and sister chromatid exchange in CHO-K1 cells and human peripheral lymphocytes by 2 hour-treatment of CdCl$_{2}$ with various concentrations was observed in relation to their frequencies and types of aberration. The frequency of chromosome aberration in CHO cells treated with CdCl$+{2}$ at G$_{1}$ was increased with dose-dependent manner. When human peripheral lymphocytes were treated with cadmium at G0 and harvested at 72 hours there after, the response was dose-dependent and all the aberrations were also chromatid types. There was no significant increase in frequencies of sister chromatid exchange in both CHO cells and human lymphocytes treated with different concentrations of cadmium. It was suggested that SCE analysis was not a good assessment method for cadmium toxicity.

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New Approach to Evaluating the Effects of Repeated Shocks Exposed to Human (반복 충격에 대한 인체 영향 평가의 새로운 방안)

  • 정완섭;권휴상
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.1088-1093
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    • 2001
  • This paper introduces new approaches attempted to evaluate quantitatively the effects of repeated shocks exposed to human. This attempt, by the members of ISO TC 108 / CS4, has been made to add a standardised draft of ISO 2631 Part 1 which covers newly the human response to repeated shocks. It contains the review of previous work related to shocks responses to human and suggests a mathematical model to predict the three-axis lumbar spine accelerations from the measured seat accelerations. The predicted accelerations are used to evaluate the vibration dose to the spine. The evaluated dose values are shown to enable the assessment of adverse health effects.

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