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Pataje G S Prasanna,
William F Blakely,
Jean-Marc Bertho,
John P Chute,
Eric P Cohen,
Ronald E Goans,
Marcy B Grace,
Patricia K Lillis-Hearne,
David C Lloyd,
Ludy C H W Lutgens,
Viktor Meineke,
Natalia I Ossetrova, Alexander Romanyukha,
Julie D Saba,
Daniel J Weisdorf,
Andrzej Wojcik,
Eduardo G Yukihara,
Terry C Pellmar
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ABSTRACT: Radiation exposures from accidents, nuclear detonations or terrorist incidents are unlikely to be homogeneous; however, current biodosimetric approaches are developed and validated primarily in whole-body irradiation models. A workshop was held at the Armed Forces Radiobiology Research Institute in May 2008 to draw attention to the need for partial-body biodosimetry, to discuss current knowledge, and to identify the gaps to be filled. A panel of international experts and the workshop attendees discussed the requirements and concepts for a path forward. This report addresses eight key areas identified by the Workshop Program Committee for future focus: (1) improved cytogenetics, (2) clinical signs and symptoms, (3) cutaneous bioindicators, (4) organ-specific biomarkers, (5) biophysical markers of dose, (6) integrated diagnostic approaches, (7) confounding factors, and (8) requirements for post-event medical follow-up. For each area, the status, advantages and limitations of existing approaches and suggestions for new directions are presented.
Radiation Research 02/2010; 173(2):245-53. · 2.68 Impact Factor
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ABSTRACT: The results of electron paramagnetic resonance (EPR) measurements in irradiated fingernails are presented. In total, 83 samples of different fingernails were studied. Five different groups of samples were selected based on the collection time of fingernail samples, their level of mechanical stress, and the number and size of clippings: (1) recently (<24 h) cut, irradiated and measured with EPR without any treatment of samples, and with rigorous control of size and number of clippings (stressed-fresh, controlled); (2) recently (<24 h) cut, irradiated and measured with EPR after application of a special treatment (10 min of water soaking, 5 min of drying time) to reduce the mechanical stress caused by cutting the samples, and with rigorous control of size and number of clippings (unstressed-fresh, controlled); (3) previously (>24 h) cut, stored at room temperature, additionally cut into small pieces immediately prior to study, irradiated and measured with EPR without any treatment of samples, and with rigorous control of size and number of clippings (stressed-old, controlled); (4) previously (>24 h) cut, stored at room temperature, additionally cut into small pieces immediately prior to the study, irradiated and measured with EPR after application of a special treatment to reduce mechanical stress caused by cut, and with rigorous control of size and number of clippings (unstressed-old, controlled); and (5) recently (<24 h) cut, irradiated and measured with EPR after application of a special treatment to reduce the mechanical stress caused by cut, and without rigorous control of size and number of clippings (unstressed-fresh, uncontrolled). Except for the fifth selected group, variability of the dose dependence inside all groups was found to be not statistically significant, although the variability among the different groups was significant. Comparison of the mean dose dependences obtained for each group allowed selection of key factors responsible for radiation sensitivity (dose response per unit of mass and dose) and the shape of dose dependence in fingernails. The major factor responsible for radiation sensitivity of fingernails was identified as their water content, which can affect radiation sensitivity up to 35%. The major factor responsible for the shape of the radiation sensitivity was identified as the mechanical stress. At a significant level of mechanical stress, the shape of the dose dependence is linear in the studied dose range (<20 Gy), and in lesser-stressed samples it is of an exponential growth including saturation, which depends on the degree of mechanical stress. In view of the findings, recommendations are discussed and presented for the appropriate protocol for EPR dose measurements in fingernails.
Biophysik 07/2009; 48(3):295-310. · 1.70 Impact Factor
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ABSTRACT: Investigations were conducted into chemical treatments suitable for concentrating enamel from cow teeth. Cow teeth could be used as alternative to human teeth for retrospective dosimetry when human teeth are not available. It is essential to remove dentin from tooth enamel for low dose radiation dosimetry in order to avoid interference to the ESR signal from organic radicals. Increasing the period of chemical treatment with KOH and NaOH reduced the signal intensity of the organic radicals. The sensitivity of the dosimetric signal from inorganic radicals increased slightly with length of treatment with NaOH, which is consistent with removal of dentin, and rose to a maximum of 20% after 5 h with KOH (40 degrees C).
Journal of Radiation Research 03/2006; 47 Suppl A:A71-4. · 1.68 Impact Factor
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ABSTRACT: The Imaging Plate (IP) technique which uses the Monte Carlo code, MCNP, to convert IP response to 90Sr concentration with varied thickness of the standard source has been proposed in this study. In order to verify the validity of simulation calculation in the proposed method, the radial distribution of IP signal has been compared between calculation and experiment. The result is, they are in good agreement. The proposed method has been applied to a cow tooth from the territory contaminated by radioactivity after the accident in the Mayak facility in the South Ural, Russia. Two samples have been prepared from the tooth, i.e., a thin sample of 1.2+/-0.2 mm in thickness and a thick sample which is a half of the tooth. The IP response has been evaluated for the thick sample using experimentally made standard sources, and multiplied by a modification factor to decide that for the thin sample. The modification factor has been determined with MCNP to be 0.83+/-0.08 for a thickness of 1.2+/-0.2 mm. Using these values, 90Sr concentration has been estimated to be 0.11 Bq/g for the thin sample and 0.12 Bq/g for the thick sample, hence they are in good agreement.
Journal of Radiation Research 03/2006; 47 Suppl A:A117-20. · 1.68 Impact Factor
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ABSTRACT: Published results of medical imaging studies which make use of contrast detail mammography (CDMAM) phantom images for analysis are difficult to compare since data are often not analyzed in the same way. In order to address this situation, the concept of ideal contrast detail curves is suggested. The ideal contrast detail curves are constructed based on the requirement of having the same product of the diameter and contrast (disk thickness) of the minimal correctly determined object for every row of the CDMAM phantom image. A correlation and comparison of five different quality parameters of the CDMAM phantom image determined for obtained ideal contrast detail curves is performed. The image quality parameters compared include: (1) contrast detail curve--a graph correlation between "minimal correct reading" diameter and disk thickness; (2) correct observation ratio--the ratio of the number of correctly identified objects to the actual total number of objects multiplied by 100; (3) image quality figure--the sum of the product of the diameter of the smallest scored object and its relative contrast; (4) figure-of-merit--the zero disk diameter value obtained from extrapolation of the contrast detail curve to the origin (e.g., zero disk diameter); and (5) k-factor--the product of the thickness and the diameter of the smallest correctly identified disks. The analysis carried out showed the existence of a nonlinear relationship between the above parameters, which means that use of different parameters of CDMAM image quality potentially can cause different conclusions about changes in image quality. Construction of the ideal contrast detail curves for CDMAM phantom is an attempt to determine the quantitative limits of the CDMAM phantom as employed for image quality evaluation. These limits are determined by the relationship between certain parameters of a digital mammography system and the set of the gold disks sizes in the CDMAM phantom. Recommendations are made on selections of CDMAM phantom regions which should be used for scoring at different image quality and which scoring methodology may be most appropriate. Special attention is also paid to the use of the CDMAM phantom for image quality assessment of digital mammography systems particularly in the vicinity of the Nyquist frequency.
Medical Physics 04/2005; 32(3):807-14. · 2.83 Impact Factor
