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Purpose: Biological dosimetry, based on the relationship between the absorbed dose after exposure to ionizing radiation and the frequency of scored aberrations, has been and continues to be an important tool for estimating the dose after exposure. Dicentric chromosomes are considered to be the most specific and sensitive aberration related to radiation exposure. Here, we established the dose-response curve following in vitro irradiation of circulating lymphocytes from healthy donors from three African countries after scoring unstable chromosomal aberrations.
Materials And Methods: Blood samples from 16 African donors were exposed to various doses (0 to 4 Gy) using an X-RAD320 x-ray system with a maximum photon energy of 250 kV at a dose rate of 0.1 Gy min. Blood lymphocytes were cultured for 48 h, and chromosomal aberrations were scored during the first mitosis by telomere and centromere staining. The distribution of dicentric chromosomes was determined.
Results: No dicentric chromosomes were found after the analysis of 2,669 first-division metaphases before in vitro exposure. We established a linear-quadratic dose-response curve based on the frequency of dicentric and ring chromosomes and calculated double-strand breaks, taking into account all scored aberrations.
Conclusion: The generation of a specific dose-response curve for African donors will allow the practice of precise biological dosimetry in these countries. This work is the first step towards realizing an African biodosimetry network and the establishment of a biological dosimetry laboratory, which could play a major role in the application of radioprotection norms.
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http://dx.doi.org/10.1097/HP.0000000000001102 | DOI Listing |
Bioelectromagnetics
September 2025
Competence Centre of Sleep Medicine, Charité -Universitaetsmedizin Berlin, Berlin, Germany.
A new whole-body exposure facility for a randomized, double-blind, cross-over provocation study investigating possible effects of 50 Hz magnetic field exposure on sleep and markers of Alzheimer's disease has been developed and dosimetrically analyzed. The exposure facility was custom-tailored for the sleep laboratory where the study was carried out and enables magnetic flux densities of up to 30 μT with a maximum field inhomogeneity of less than ± 20%. Exposure is applied fully software-controlled and in a blinded and randomized manner.
View Article and Find Full Text PDFMed Phys
September 2025
Heidelberg Institute for Radiation Oncology (HIRO), National Center for Research in Radiation Oncology (NCRO), Heidelberg, Germany.
Background: As advanced treatment plans increasingly include optimizing both dose and linear energy transfer (LET), there is a growing demand for tools to measure LET in clinical settings. Although various detection systems have been investigated in this pursuit, the scarcity of detectors capable of providing per-ion data for a fast and streamlined verification of LET distributions remains an issue. Silicon pixel detector technology bridges this gap by enabling rapid tracking of single-ion energy deposition.
View Article and Find Full Text PDFPhys Med Biol
September 2025
Massachusetts General Hospital Athinoula A Martinos Center for Biomedical Imaging, 149 13th St, Charlestown, Massachusetts, 02129, UNITED STATES.
While external beam radiotherapy relies heavily on pre-treatment imaging for advanced treatment planning and radiation dosimetry, tools for predicting local dose delivery in systemic radiopharmaceutical therapies have generally lagged behind. Furthermore, targeted alpha particle-emitting radiopharmaceuticals, with their uniquely short range and high-energy dose deposition, require specialized dosimetry methods at the micro- and mesoscale. Magnetic resonance imaging methods may represent the missing link between standard diagnostic tumor imaging and personalized radionuclide treatment planning for patients.
View Article and Find Full Text PDFBJR Open
January 2025
Adem Crosby Centre-Radiation Oncology, Sunshine Coast University Hospital, Birtinya, QLD 4575, Australia.
Objectives: Xerostomia toxicity continues to contribute towards a decrease in quality of life in head and neck cancer patients. Diffusion weighted MRI and the associated apparent diffusion coefficient (ADC) may identify the radiosensitive region within the parotid gland (PG). This study retrospectively assesses the feasibility of using percentile threshold values from the ADC map to generate a biological at-risk volume (BRV).
View Article and Find Full Text PDFWorld J Urol
September 2025
Department of Urology, Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, No. 23 Pingjiang Road, Hexi District, Tianjin, 300211, People's Republic of China.
Purpose: To compare the diagnostic accuracy of intraoperative endoscopic assessment with postoperative low-dose computed tomography (LDCT) for determining stone-free status (SFS) following retrograde vacuum-assisted dedusting lithotripsy (VADL) using a tip-flexible vacuum-assisted suction ureteral access sheath (tFVS-UAS) and evaluate the feasibility of replacing routine LDCT with intraoperative evaluation.
Methods: This single-center retrospective study analyzed 1,105 patients undergoing unilateral VADL (December 2022-December 2024). All VADL procedures were performed retrograde using tFVS-UAS.