Radiation And Environmental Biophysics[JOURNAL]
Sun
200 papers
Dosimetric and radiobiological comparison of IMRT, VMAT, and helical tomotherapy planning techniques in hippocampal sparing whole brain radiotherapy with simultaneous integrated boost for multiple brain metastases.
Balasubramanian S, Shobana MK, Anabalagan D … +3 more , Thanasekar P, Joel S, Chaudhary P
Radiat Environ Biophys · 2024 Mar · PMID 38194100 · Publisher ↗
To compare treatment planning and dosimetric outcomes for hippocampal sparing whole brain radiotherapy (WBRT) with the simultaneous integrated boost (SIB) in brain metastasis (BM) patients using tumour control probabilit...
To compare treatment planning and dosimetric outcomes for hippocampal sparing whole brain radiotherapy (WBRT) with the simultaneous integrated boost (SIB) in brain metastasis (BM) patients using tumour control probability (TCP) and normal tissue complication probability (NTCP) formalism between IMRT, VMAT, and HT techniques. In this retrospective study, the treatment data of 20 BM patients who typically received whole brain radiation with SIB treatment were used. Prescription doses of 30 Gy and 36 Gy was delivered in 10 fractions for WBRT and SIB, respectively. Niemierko and LKB models were applied for calculating TCP and NTCP. All the plans were evaluated for the RTOG 0933 protocol criteria and found acceptable. Additionally, the homogeneity of the PTV boost is 0.07 ± 0.01, 0.1 ± 0.04, and 0.08 ± 0.02 for IMRT, VMAT, and HT, respectively (P < 0.05). The percentage of TCP for the PTV boost was 99.99 ± 0.003, 99.98 ± 0.004, and 99.99 ± 0.002 of IMRT, VMAT, and HT, respectively, (P < 0.005). The NTCP value of the lenses was higher with the VMAT plan as compared to IMRT and HT Plans. The hippocampal NTCP values are equal in all three planning proficiencies. The techniques like IMRT, VMAT, and HT can reduce the dose received by hippocampus to the dosimetric threshold during the delivery of WBRT with hippocampal sparing and can simultaneously boost multiple metastases. Overall, the high-quality dose distribution, TCP, and NTCP comparison between all three planning techniques show that the HT technique has better results when compared to the VMAT and IMRT techniques.
Evaluation of organ dose using size-specific dose estimation (SSDE) and related cancer risk due to chest CT scan during the COVID-19 pandemic.
Robatjazi M, Moayed M, Baghani HR … +2 more , Molazadeh M, Shomoossi N
Radiat Environ Biophys · 2024 Mar · PMID 38185693 · Publisher ↗
This study aimed to estimate lung and breast doses for individual patients using the size-specific dose estimate (SSDE) method, as well as calculating effective doses, in patients who underwent chest CT scans during the...
This study aimed to estimate lung and breast doses for individual patients using the size-specific dose estimate (SSDE) method, as well as calculating effective doses, in patients who underwent chest CT scans during the COVID-19 pandemic. Cancer risk incidence was estimated using excess relative risk (ERR), excess absolute risk (EAR), and lifetime attributable risk (LAR) models from the Biological Effects of Ionizing Radiation Report VII (BEIR-VII). Data from about 570 patients who underwent CT scans for COVID-19 screening were utilized for this study. Using the header of the CT images in a Python script, SSDE and effective dose were calculated for each patient. The SSDE obtained by water equivalent effective diameter (wSSDE) was considered as lung and breast dose, and applied in organ-specific cancer risk estimation. The mean wSSDE value for females (13.3 mGy) was slightly higher than that for males (13.1 mGy), but the difference was not statistically significant (P value = 0.41). No significant differences were observed between males and females in terms of calculated EAR and ERR for lung cancer at 5 and 30 years after exposure (P value = 0.47, 0.46, respectively). Similarly, there was no significant difference in lung cancer LAR values between females and males (P value = 0.48). The results also indicated a decrease in LAR values for both lung and breast cancers with increasing exposure age. In accordance with the ALARA (as low as reasonably achievable) principle, it is important for medical staff and the general public to consider the benefits of CT imaging in detecting such infections. Additionally, imaging medical physicists and CT scan experts should optimize imaging protocols and strike a balance between image quality for detecting abnormalities and radiation dose, all while adhering to the ALARA principle.
Comparison of CBCT radiation doses with conventional radiographs in TMJ imaging using Monte Carlo simulations.
Deniz Y, Eren H, Sessiz R … +1 more , Coşan Ata G
Radiat Environ Biophys · 2024 Mar · PMID 38182962 · Publisher ↗
Three-dimensional imaging methods are widely used for evaluation of bony changes of temporomandibular joint (TMJ). Besides, lateral and posterio-anterior TMJ projections in both closed- and open-jaw positions for each te...
Three-dimensional imaging methods are widely used for evaluation of bony changes of temporomandibular joint (TMJ). Besides, lateral and posterio-anterior TMJ projections in both closed- and open-jaw positions for each temporomandibular joint are used as two-dimensional diagnostic tools. The purpose of the present study was to compare effective and mean organ absorbed doses of plain radiography techniques with those of different modalities of cone beam computed tomography (CBCT) scanning of an adult's temporomandibular joint. PCXMC 2.0 software was used to calculate mean organ and effective doses. A NewTom CBCT device (Newtom 5G XL; QR systems; Verona, Italy) was simulated at 360° rotation using a 6 × 6 cm FOV in standard and high-resolution modes. Lateral and posterio-anterior TMJ plain projections were simulated according to recommendations of the manufacturer of the Planmeca ProMax 2D S3 device. Doses for both projections were simulated with Monte Carlo methods and the International Commission on radiological protection adult reference computational phantoms. The highest mean organ absorbed doses occurred in bone surfaces, salivary glands, and skull for posterio-anterior TMJ and lateral TMJ, and for CBCT scanning in all examinations. The effective doses of posterio-anterior and lateral TMJ plain radiographs were found to be higher than those of the Standard Mode-Eco Scan CBCT. Therefore, the lowest effective dose was calculated in Standard Mode-Eco Scan CBCT. It is concluded that NewTom 5G XL Standard Mode-Eco Scan CBCT can be used instead of plain radiographs (lateral and posterio-anterior TMJ) in temporomandibular joint imaging as it allows visualizing the three-dimensional structure of the temporomandibular joint as an advantage.
Lifetime excess absolute risk for lung cancer due to exposure to radon: results of the pooled uranium miners cohort study PUMA.
Kreuzer M, Sommer M, Deffner V … +12 more , Bertke S, Demers PA, Kelly-Reif K, Laurier D, Rage E, Richardson DB, Samet JM, Schubauer-Berigan MK, Tomasek L, Wiggins C, Zablotska LB, Fenske N
Radiat Environ Biophys · 2024 Mar · PMID 38172372 · Full text
The Pooled Uranium Miners Analysis (PUMA) study is the largest uranium miners cohort with 119,709 miners, 4.3 million person-years at risk and 7754 lung cancer deaths. Excess relative rate (ERR) estimates for lung cancer...
The Pooled Uranium Miners Analysis (PUMA) study is the largest uranium miners cohort with 119,709 miners, 4.3 million person-years at risk and 7754 lung cancer deaths. Excess relative rate (ERR) estimates for lung cancer mortality per unit of cumulative exposure to radon progeny in working level months (WLM) based on the PUMA study have been reported. The ERR/WLM was modified by attained age, time since exposure or age at exposure, and exposure rate. This pattern was found for the full PUMA cohort and the 1960 + sub-cohort, i.e., miners hired in 1960 or later with chronic low radon exposures and exposure rates. The aim of the present paper is to calculate the lifetime excess absolute risk (LEAR) of lung cancer mortality per WLM using the PUMA risk models, as well as risk models derived in previously published smaller uranium miner studies, some of which are included in PUMA. The same methods were applied for all risk models, i.e., relative risk projection up to <95 years of age, an exposure scenario of 2 WLM per year from age 18-64 years, and baseline mortality rates representing a mixed Euro-American-Asian population. Depending upon the choice of model, the estimated LEAR per WLM are 5.38 × 10 or 5.57 × 10 in the full PUMA cohort and 7.50 × 10 or 7.66 × 10 in the PUMA 1960 + sub-cohort, respectively. The LEAR per WLM estimates derived from risk models reported for previously published uranium miners studies range from 2.5 × 10 to 9.2 × 10. PUMA strengthens knowledge on the radon-related lung cancer LEAR, a useful way to translate models for policy purposes.
A comparative dose-escalation analysis for reirradiated cancer patients with and without appropriate dose mapping.
Sarkar B, Biswal SS, Shahid T … +5 more , Appunu K, Bhattacharya J, Ganesh T, Munshi A, Das A
Radiat Environ Biophys · 2024 Mar · PMID 38078988 · Publisher ↗
This study aims to compare dose escalation between two groups of reirradiated cancer patients, one with the previous contour and radiotherapy plan available on the treatment planning system and the other without. First g...
This study aims to compare dose escalation between two groups of reirradiated cancer patients, one with the previous contour and radiotherapy plan available on the treatment planning system and the other without. First group is identified as DICOM-group, while the other one is called non-DICOM group. The current study included 89 patients, 57 in the DICOM, and 32 in the non-DICOM group, who received reirradiation for recurrent or second primary tumours between 2019 and 2021. For the DICOM group, doses to 0.2cc volume for spine, brainstem, and optic apparatus from first radiation were converted into structures and transferred to reirradiation CT using deformable registration. First, one radiotherapy plan was created using the doctor prescribed dose (baseline prescription RxD_B); further an escalated dose (RxD_E) plan, taking into account all the dose volume parameters from previous radiation, was created only for DICOM group. In non-DICOM group patients were planned only for RxD_B. The maximum accepted dose escalation was 21 Gy. Radiotherapy prescription dose during earlier (first) treatment in DICOM and non-DICOM groups were 61 ± 5.6 Gy and 30-66 Gy, respectively. DICOM and non-DICOM groups had nearly identical baseline doses: 52.5 ± 10.7 Gy and 50.6 ± 6.9 Gy (difference 1.9 ± 12.7 Gy). Dose escalation was possible for 51 out of 57 patients in the DICOM-group. Average escalated dose in DICOM-group was 59.2 ± 6.2 Gy, with an incremental dose of 6.7 ± 12.4 Gy from the baseline prescription. No dose escalation was opted for in the non-DICOM group due to the unavailability of dose volume information from previous radiation. Reirradiation for head and neck cases allowed for a moderate to high dose escalation, facilitated by the presence of pertinent DICOM information from the initial radiotherapy.
The activity of Pb in cigarette smoked in Kazakhstan.
Zaripova Y, Dyachkov V, Bigeldiyeva M … +1 more , Yushkov A
Radiat Environ Biophys · 2024 Mar · PMID 38055043 · Publisher ↗
The radon decay product Pb is a known component of tobacco. In this study, the activity concentration of Pb in the most popular cigarette brands (six samples) for Kazakhstan consumers was determined by beta spectrometry....
The radon decay product Pb is a known component of tobacco. In this study, the activity concentration of Pb in the most popular cigarette brands (six samples) for Kazakhstan consumers was determined by beta spectrometry. The activity levels of Pb ranged between 2.69 ± 0.27 and 27.42 ± 2.74 mBq per cigarette. Higher activity concentrations for Pb were found in Sample No.4 and showed an excess of the world average by 1.8 times. The average activity concentrations of Pb in cigarette tobacco were 10.42 ± 1.04 mBq cig. The daily activities inhaled in the lungs of a smoker, and the resulting effective doses due to cigarette smoking were calculated. Effective doses per year due to cigarette smoking were calculated assuming that 42.13% of the Pb in tobacco were retained in the lungs of the smokers. It is concluded that for a smoker in Kazakhstan, the average effective dose ranges from 9.1 ± 0.9 μSv/year to 92.8 ± 9.3 μSv/year for a cigarette consumption of one pack of cigarettes per day. The results indicate that the annual effective doses from inhalation of Pb due to smoking one pack of cigarettes per day are from 7 to 58 times (for different types of cigarettes) greater than the annual effective doses from ingestion of radionuclides via the diet.
Immune status of people living in the Tande-Tande sub-village (Indonesia), an area with high indoor radon concentration.
Purnami S, Ramadhani D, Oktariyani TA … +10 more , Suvifan VA, Tetriana D, Sugoro I, Rahajeng N, Wanandi SI, Wibowo H, Yamaguchi M, Kashiwakura I, Syaifudin M, Widowati R
Radiat Environ Biophys · 2023 Nov · PMID 37897500 · Publisher ↗
On Earth, there are significant variations in terms of exposure to naturally occurring radiation among different areas. Radon, a naturally-occurring radioactive gas that is the primary cause of lung cancer in nonsmokers...
On Earth, there are significant variations in terms of exposure to naturally occurring radiation among different areas. Radon, a naturally-occurring radioactive gas that is the primary cause of lung cancer in nonsmokers and the second most prevalent cause among smokers, poses a considerable risk. Indoor radon, in particular, constitutes the most substantial source of natural radiation to which individuals are exposed. This study assessed the immune status of a population chronically exposed to high indoor radon concentration in Indonesia. Fifty-seven subjects from the Tande-Tande sub-village (high indoor radon concentration area) were compared to fifty-three participants living in the Topoyo village (low concentration area). We contrasted the immunological conditions of these two populations by measuring levels of tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-4 (IL-4), and IL-10 in serum. Moreover, we also measured levels of the nuclear factor kappa B (NF-κB), superoxide dismutase (SOD), glutathione peroxidase (GPX), and protein kinase B in its phosphorylated (pAkt) and non-phosphorylated form (Akt) in peripheral blood mononuclear cells (PBMCs) of a subset of participants (31 from each population). TNF-α, IFN-γ, and IL-4 levels in Tande-Tande sub-village inhabitants were significantly lower than those in the control group living in the Topoyo village (p = 0.001, p = 0.017, and p = 0.002). The concentration of IL-10 also tended to be lower in people living in the high indoor radon concentration area, but it did not differ significantly between Tande-Tande sub-village inhabitants and Topoyo inhabitants (p = 0.106). Protein levels of NF-κB, pAkt, and Akt in Tande-Tande sub-village inhabitants also did not differ significantly between Tande-Tande sub-village inhabitants and Topoyo inhabitants (p = 0.234, p = 0.210, and p = 0.657). Similarly, activities of SOD and GPX did not differ significantly between the two populations (p = 0.569 and p = 0.949). Overall, despite their chronic exposure to high indoor radon concentrations, our study revealed no increase in the levels of TNF-α, IFN-γ, IL-10, IL-4, SOD, and GPX in the inhabitants of Tande-Tande sub-village compared with people living in the Topoyo village. Furthermore, our study demonstrated no activation in the Akt pathway, as indicated by the pAkt/Akt ratio observed in PBMC lysates of individuals residing in the Tande-Tande sub-village.
Modelling DTPA therapy following Am contamination in rats.
Kastl M, Grémy O, Lamart S … +3 more , Giussani A, Li WB, Hoeschen C
Radiat Environ Biophys · 2023 Nov · PMID 37831188 · Full text
A major challenge in modelling the decorporation of actinides (An), such as americium (Am), with DTPA (diethylenetriaminepentaacetic acid) is the fact that standard biokinetic models become inadequate for assessing radio...
A major challenge in modelling the decorporation of actinides (An), such as americium (Am), with DTPA (diethylenetriaminepentaacetic acid) is the fact that standard biokinetic models become inadequate for assessing radionuclide intake and estimating the resulting dose, as DTPA perturbs the regular biokinetics of the radionuclide. At present, most attempts existing in the literature are empirical and developed mainly for the interpretation of one or a limited number of specific incorporation cases. Recently, several approaches have been presented with the aim of developing a generic model, one of which reported the unperturbed biokinetics of plutonium (Pu), the chelation process and the behaviour of the chelated compound An-DTPA with a single model structure. The aim of the approach described in this present work is the development of a generic model that is able to describe the biokinetics of Am, DTPA and the chelate Am-DTPA simultaneously. Since accidental intakes in humans present many unknowns and large uncertainties, data from controlled studies in animals were used. In these studies, different amounts of DTPA were administered at different times after contamination with known quantities of Am. To account for the enhancement of faecal excretion and reduction in liver retention, DTPA is assumed to chelate Am not only in extracellular fluids, but also in hepatocytes. A good agreement was found between the predictions of the proposed model and the experimental results for urinary and faecal excretion and accumulation and retention in the liver. However, the decorporation from the skeletal compartment could not be reproduced satisfactorily under these simple assumptions.
Behavioral performance and microglial status in mice after moderate dose of proton irradiation.
Sorokina SS, Malkov AE, Rozanova OM … +2 more , Smirnova EN, Shemyakov AE
Radiat Environ Biophys · 2023 Nov · PMID 37794305 · Publisher ↗
Cognitive impairment is a remote effect of gamma radiation treatment of malignancies. The major part of the studies on the effect of proton irradiation (a promising alternative in the treatment of radio-resistant tumors...
Cognitive impairment is a remote effect of gamma radiation treatment of malignancies. The major part of the studies on the effect of proton irradiation (a promising alternative in the treatment of radio-resistant tumors and tumors located close to critical organs) on the cognitive abilities of laboratory animals and their relation to morphological changes in the brain is rather contradictory. The aim of this study was to investigate cognitive functions and the dynamics of changes in morphological parameters of hippocampal microglial cells after 7.5 Gy of proton irradiation. Two months after the cranial irradiation, 8- to 9-week-old male SHK mice were tested for total activity, spatial learning, as well as long- and short-term hippocampus-dependent memory. To estimate the morphological parameters of microglia, brain slices of control and irradiated animals each with different time after proton irradiation (24 h, 7 days, 1 month) were stained for microglial marker Iba-1. No changes in behavior or deficits in short-term and long-term hippocampus-dependent memory were found, but an impairment of episodic memory was observed. A change in the morphology of hippocampal microglial cells, which is characteristic of the transition of cells to an activated state, was detected. One day after proton exposure in the brain tissue, a slight decrease in cell density was observed, which was restored to the control level by the 30th day after treatment. The results obtained may be promising with regard to the future use of using high doses of protons per fraction in the irradiation of tumors.
Fractal analysis of the mandible cortical bone: correlation among fractal dimension values obtained by two processing methods from periapical radiograph and micro-computed tomography with cone-beam computed tomography.
de Oliveira Loures A, de Abreu M, Devito KL … +3 more , Grisolia-Seifert EF, Jähn-Rickert K, Rabelo GD
Radiat Environ Biophys · 2023 Nov · PMID 37792108 · Publisher ↗
The objectives of the present study were to assess Fractal Dimension (FD) values in the mandible cortical bone obtained from digital periapical radiographs (DPR), high-resolution microtomography (µCT), and cone-beam comp...
The objectives of the present study were to assess Fractal Dimension (FD) values in the mandible cortical bone obtained from digital periapical radiographs (DPR), high-resolution microtomography (µCT), and cone-beam computed tomography (CBCT), by two processing methods: binarization (FD.b) and grayscale-based method (FD.f) and, finally, to identify the correlation among these values with other micro-architectural parameters. For this, a prospective study was conducted on 18 healthy individuals (mean age 23 ± 2.4 years old) who underwent third molar extraction. Pre-operative CBCT scans were conducted, bone fragments were removed from the retro-molar region, and DPR and µCT were performed on those bone samples. FD.b and FD.f values were calculated using three parasagittal sections for CBCT, one image for DPR, and three sections for µCT. The 3D bone microarchitecture was analyzed in µCT (voxel size: 19 µm). As a result, FD.b mean values of 1.55 ± 0.02 and 1.80 ± 0.01 were obtained for CBCT and µCT, respectively. Furthermore, FD.f mean values of 1.22 ± 0.12 for DPR, 0.99 ± 0.04 for CBCT, and 1.30 ± 0.07 for µCT were obtained. Both FD.b and FD.f values showed a good agreement. FD.f was negatively correlated with the standard deviation of the mean gray value (p = 0.003) for DPR and intra-cortical bone surface (p = 0.02) for µCT. In conclusion, image processing with or without binarization revealed different values for FD, although showing agreement. The grayscale-based method retrieved FD values correlated with the gray levels and the cortical porous network, which means that FD can be a valuable index for mandibular cortical bone evaluation. FD is associated with mineralization and microarchitecture. Nevertheless, there was no correlation between FD values obtained from low- (DPR) and high-resolution (µCT) X-ray modalities with FD obtained from the in vivo CBCT.
Updated risk models for lung cancer due to radon exposure in the German Wismut cohort of uranium miners, 1946-2018.
Kreuzer M, Deffner V, Sommer M … +1 more , Fenske N
Radiat Environ Biophys · 2023 Nov · PMID 37695330 · Full text
UNSCEAR recently recommended that future research on the lung cancer risk at low radon exposures or exposure rates should focus on more contemporary uranium miners. For this purpose, risk models in the German Wismut coho...
UNSCEAR recently recommended that future research on the lung cancer risk at low radon exposures or exposure rates should focus on more contemporary uranium miners. For this purpose, risk models in the German Wismut cohort of uranium miners were updated extending the follow-up period by 5 years to 1946-2018. The full cohort (n = 58,972) and specifically the 1960 + sub-cohort of miners first hired in 1960 or later (n = 26,764) were analyzed. The 1960 + sub-cohort is characterized by low protracted radon exposure of high quality of measurements. Internal Poisson regression was used to estimate the excess relative risk (ERR) for lung cancer per cumulative radon exposure in Working Level Months (WLM). Applying the BEIR VI exposure-age-concentration model, the ERR/100 WLM was 2.50 (95% confidence interval (CI) 0.81; 4.18) and 6.92 (95% CI < 0; 16.59) among miners with attained age < 55 years, time since exposure 5-14 years, and annual exposure rates < 0.5 WL in the full (n = 4329 lung cancer deaths) and in the 1960 + sub-cohort (n = 663 lung cancer deaths), respectively. Both ERR/WLM decreased with older attained ages, increasing time since exposure, and higher exposure rates. Findings of the 1960 + sub-cohort are in line with those from large pooled studies, and ERR/WLM are about two times higher than in the full Wismut cohort. Notably, 20-30 years after closure of the Wismut mines in 1990, the estimated fraction of lung cancer deaths attributable to occupational radon exposure is still 26% in the full Wismut cohort and 19% in the 1960 + sub-cohort, respectively. This demonstrates the need for radiation protection against radon.
Indoor radon concentrations in kindergartens in three Bulgarian districts.
Chobanova N, Kunovska B, Djunakova D … +4 more , Djounova J, Stojanovska Z, Angelova A, Ivanova K
Radiat Environ Biophys · 2023 Nov · PMID 37541987 · Publisher ↗
This article examines the results of a study of radon concentrations in kindergartens in three districts of north-western Bulgaria. For the period from December 2019 to May 2020, passive radon measurements were accomplis...
This article examines the results of a study of radon concentrations in kindergartens in three districts of north-western Bulgaria. For the period from December 2019 to May 2020, passive radon measurements were accomplished in 1490 premises of 130 kindergartens. The highest arithmetic mean (AM) value of 219 Bq m and geometric mean (GM) value of 156 Bq m radon concentration were found in the state kindergartens of the Vratsa district. The radon values for the remaining two districts are as follows: Lovech-AM = 156 Bq m and GM = 114 Bq m; Montana-AM = 125 Bq m and GM = 88 Bq m. The effects of various factors on the radon concentration including district, year of building construction, presence of basement, place of premise, wall, and floor interior covering materials, and presence of a ventilation system were investigated. Factor Analysis was used to assess the combined effects of those factors on indoor radon concentration. The results revealed three combinations of the investigated factors: the first combined the district in which the kindergartens were located and the materials used for the floor of the premises, the second combined the year of construction of the building and the presence of a building foundation, and the third combined the rest of the investigated factors. It is concluded that a regional assessment of predictors of radon variability is needed. The walls in kindergartens should not be covered by gypsum, and floors should not be made from materials that can easily develop cracks such as terra cotta. The installation of a ventilation system reduces the radon concentrations in the premises, which is of particular importance in cases where the measured value is above the national reference levels.
Recall of residential history and dietary habits during pregnancy and lactation in the distant past: reliability of questionnaire-based radiation doses for persons exposed in utero and early life.
Drozdovitch V, Kukhta T, Minenko V … +5 more , Trofimik S, Veyalkin I, Yauseyenka V, Mabuchi K, Rozhko A
Radiat Environ Biophys · 2023 Nov · PMID 37541986 · Full text
This study evaluates the reliability of information obtained by standardized questionnaires used in by personal interviews for estimation of radiation thyroid doses of 1065 individuals in the Belarusian cohort of individ...
This study evaluates the reliability of information obtained by standardized questionnaires used in by personal interviews for estimation of radiation thyroid doses of 1065 individuals in the Belarusian cohort of individuals who were exposed in utero and early life following the Chernobyl accident in April 1986. Data from two interviews conducted in 2012-2017 and in 2018-2022 with mothers, who were pregnant or gave birth shortly after the Chernobyl accident, were analysed. The most reliable answers dealt with various attributes related to residential history. In contrast, the reliability of answers regarding consumption rates of milk from privately owned cows or trade network was moderate, while the agreement in responses for consumption of milk products and leafy vegetables was fair. Information from the two interviews was used to calculate thyroid doses received by the cohort members. Specifically, 'model-based' thyroid doses due to I were estimated using input data on individual residential history and food consumption reported during the personal interviews and ecological data (I ground deposition in the corresponding settlements). In addition, for a subset of cohort subjects (n = 205) whose mothers were measured for I thyroid activity, 'measurement-based' thyroid doses were calculated by adjusting the model-based dose using a scaling factor that is defined as the ratio of measured I thyroid activity to model-based I thyroid activity calculated for the date of measurement. A moderate agreement was observed for total (prenatal and postnatal) model-based thyroid doses due to I intake, the arithmetic mean ± standard deviation for the Jaccard similarity coefficient ([Formula: see text]) was 0.45 ± 0.34 (median = 0.39), while measurement-based doses showed a much better agreement with a [Formula: see text] of 0.78 ± 0.29 (median = 0.93). For model-based thyroid doses from external irradiation and from ingestion of Cs and Cs, [Formula: see text] was 0.82 ± 0.23 (median = 0.90) and 0.84 ± 0.24 (median = 0.96), respectively. Measurement-based doses due to ingestion of radiocaesium isotopes resulted in an almost perfect agreement, [Formula: see text] was 0.91 ± 0.19 (median = 1.0). The present findings suggest that long-term memory recall can be reliable, if a person is asked about unique or important life events, such as pregnancy and childbirth occurring around the time of a nuclear reactor accident. However, the substantial difference (more than 10 times) observed for model-bases doses calculated using the two questionnaires represents an important source of human factor uncertainties that needs to be considered in any dose response analyses. Other lessons learned from this study are that (i) individual measurements of radionuclides in the human body are the most valuable source of information for estimating radiation doses, and (ii) whenever a radiation accident occurs, a sample of affected people should be asked to keep a diary, if at all possible.
Mapping in a radon-prone area in Adamawa region, Cameroon, by measurement of radon activity concentration in soil.
Bachirou S, Saïdou, Kranrod C … +6 more , Nkoulou Ii JEN, Bongue D, Abba HY, Hosoda M, Njock MGK, Tokonami S
Radiat Environ Biophys · 2023 Nov · PMID 37535128 · Publisher ↗
The radon-prone area of the Adamawa region in Cameroon is characterized by high natural radiation background resulting from the high concentrations of radium-226, thorium-232, and indoor radon. To produce a radon-risk ma...
The radon-prone area of the Adamawa region in Cameroon is characterized by high natural radiation background resulting from the high concentrations of radium-226, thorium-232, and indoor radon. To produce a radon-risk map, radon measurements in soil were carried out in the city of Ngaoundere. The radon activity concentration in soil gas ranged from 256 to 166 kBq m with a mean of 80 kBq m and a standard deviation of 38 kBq m. The area is mostly classified as high risk (80%) according to the Swedish classification, and 20% as medium risk. A low-risk area was not observed. Granite-like geology sites were characterized by higher radon concentration. A ratio of about 295:1 was obtained for soil radon gas to indoor radon concentrations, with a positive correlation (R = 0.40), and a transfer factor of 3 per mil. These results demonstrate that in situ measurements of radon concentration in soil can provide accurate information on the level of indoor radon concentrations. Geostatistical and deterministic interpolation techniques have been used to obtain a radon map by comparing the suitability of ordinary kriging and inverse-distance-weighted (IDW) interpolation methods. It turned out that there is not much difference in the prediction errors of the two techniques (Root Mean Square Error = 34.4 for ordinary kriging and 34.3 for IDW). It is concluded that both methods give acceptable results. In situ measurements and geostatistical analysis allow assessment of expected indoor radon exposure in a given area at reduced costs and time required. However, for the investigated area, more research is needed to produce reliable radon-risk maps.
Superparamagnetic iron oxide nanoparticles induce persistent large foci of DNA damage in human melanoma cells post-irradiation.
Grissi C, Taverna Porro M, Perona M … +8 more , Atia M, Negrin L, Moreno MS, Sacanell J, Olivera MS, Del Grosso M, Durán H, Ibañez IL
Radiat Environ Biophys · 2023 Aug · PMID 37452828 · Publisher ↗
The synergy of superparamagnetic iron oxide nanoparticles (SPIONs) and ionizing radiation (IR), attributed to reactive oxygen species (ROS) and DNA double-strand breaks (DSBs) increase, was widely investigated in differe...
The synergy of superparamagnetic iron oxide nanoparticles (SPIONs) and ionizing radiation (IR), attributed to reactive oxygen species (ROS) and DNA double-strand breaks (DSBs) increase, was widely investigated in different cancers, but scarcely in melanoma. Herein, SPIONs were evaluated as radiosensitizers in A-375 human melanoma cells. Moreover, the effect of the combined treatment of SPIONs and gamma irradiation (SPIONs-IR) was assessed at the DNA level, where DSBs induction and their repair capacity were studied. SPIONs were synthesized, stabilized by poly(ethylene glycol) methyl ether and physicochemically characterized by high resolution-transmission electron microscopy (HR-TEM), X-ray diffraction and magnetometry and dynamic light scattering. The obtained nanoparticles showing superparamagnetic behavior and low dispersion in shape and sizes were tested in A-375 cells. The intracellular internalization of SPIONs was verified by HR-TEM and quantified by inductively coupled plasma atomic emission spectroscopy. Cells treated with SPIONs exhibited high ROS levels without associated cytotoxicity. Next, a significant radiosensitization in SPIONs-IR vs. control (IR) cells was demonstrated at 1 Gy of gamma radiation. Furthermore, a decreased DSBs repair capacity in SPIONs-IR vs. IR-treated cells was evidenced by the size increase of persistent phosphorylated H2AX foci at 24 h post-irradiation. In conclusion, these nanoparticles show the potential to radiosensitize melanoma cells by the induction of unrepairable DNA damage.
In support of ICRP's call to action to strengthen expertise in radiological protection worldwide.
Newhauser WD, Williams JP, Noska MA … +4 more , Bluth EI, Townsend LW, Tolmachev SY, Dewji SA
Radiat Environ Biophys · 2023 Aug · PMID 37436488 · Publisher ↗
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The protective effects of ginseng on x-irradiation-induced intestinal damage in rats.
Ozdemir A, Tumkaya L, Mercantepe T … +7 more , Celik Samanci T, Uyan M, Kalcan S, Demiral G, Pergel A, Yilmaz Kutlu E, Kilic Yilmaz H
Radiat Environ Biophys · 2023 Aug · PMID 37410120 · Publisher ↗
Although radiotherapy is widely employed in the treatment of various malignancies in oncology patients, its use is limited by the toxic effects it causes in surrounding tissues, including the gastrointestinal system. Kor...
Although radiotherapy is widely employed in the treatment of various malignancies in oncology patients, its use is limited by the toxic effects it causes in surrounding tissues, including the gastrointestinal system. Korean Red Ginseng (KRG) is a traditional drug reported to possess antioxidant and restorative properties in various studies. The purpose of the present study was to investigate the protective effects of KRG against radiation-associated small intestinal damage. Twenty-four male Sprague Dawley rats were randomly assigned into three groups. No procedure was performed on Group 1 (control) during the experiment, while Group 2 (x-irradiation) was exposed to radiation only. Group 3 (x-irradiation + ginseng) received ginseng via the intraperitoneal route for a week prior to x-irradiation. The rats were killed 24 h after radiation. Small intestinal tissues were evaluated using histochemical and biochemical methods. An increase in malondialdehyde (MDA) levels and a decrease in glutathione (GSH) were observed in the x-irradiation group compared to the control group. KRG caused a decrease in MDA and caspase-3 activity and an increase in GSH. Our findings show that it can prevent damage and apoptotic cell death caused by x-irradiation in intestinal tissue and can therefore play a protective role against intestinal injury in patients receiving radiotherapy.
Structural properties and electron spin resonance (ESR) dose estimations of fossil cow tooth enamel from Köşk Höyük, Turkey.
Karataş Ö, Kayalı R, Ercan HÜ
Radiat Environ Biophys · 2023 Aug · PMID 37410119 · Publisher ↗
In this work, two cow teeth collected from the Niğde-Köşk Höyük excavation site in Turkey were studied for characterization and dosimetric purposes. Each tooth sample was prepared by applying mechanical and chemical meth...
In this work, two cow teeth collected from the Niğde-Köşk Höyük excavation site in Turkey were studied for characterization and dosimetric purposes. Each tooth sample was prepared by applying mechanical and chemical methods to obtain the enamel fractions. To do this, mineralogical and elemental concentration properties of the tooth enamels were investigated by performing X-ray diffraction (XRD) and scanning electron microscopy coupled with energy-dispersive X-ray measurements (SEM-EDX). It was found that the enamel structures contained a highly hydroxyapatite crystalline without any characteristic impurities. The dose response of the tooth enamels was determined by using the electron spin resonance (ESR) method. Absorbed radiation doses were calculated as (26.05 ± 0.15) Gy and (25.48 ± 0.18) Gy by the additive dose method using both natural radiation doses and artificial irradiation doses of the enamel samples. It is concluded that these samples could be used to reconstruct radiation doses. This result can be considered as a precursor for future ESR dosimetry/dating studies of other fossil teeth at this excavation site.
Vibrational spectroscopies for biochemical investigation of X-ray exposure effects on SH-SY5Y human neuroblastoma cells.
Ricciardi V, Lasalvia M, Perna G … +5 more , Portaccio M, Delfino I, Lepore M, Capozzi V, Manti L
Radiat Environ Biophys · 2023 Aug · PMID 37392215 · Publisher ↗
Neuroblastoma is the most recurring cancer in childhood and adolescence. The SH-SY5Y neuroblastoma cell line is generally adopted for elaborating new therapeutical approaches and/or elaborating strategies for the prevent...
Neuroblastoma is the most recurring cancer in childhood and adolescence. The SH-SY5Y neuroblastoma cell line is generally adopted for elaborating new therapeutical approaches and/or elaborating strategies for the prevention of central nervous system disturbances. In fact, it represents a valid model system for investigating in vitro the effects on the brain of X-ray exposure using vibrational spectroscopies that can detect early radiation-induced molecular alterations of potential clinical usefulness. In recent years, we dedicated significant efforts in the use of Fourier-transform and Raman microspectroscopy techniques for characterizing such radiation-induced effects on SH-SY5Y cells by examining the contributions from different cell components (DNA, proteins, lipids, and carbohydrates) to the vibrational spectra. In this review, we aim at revising and comparing the main results of our studies to provide a wide outlook of the latest outcomes and a framework for future radiobiology research using vibrational spectroscopies. A short description of our experimental approaches and data analysis procedures is also reported.
Distributions of energy imparted to a micro-volume by secondary charged fragments of nuclear interactions in space radiation field.
Fedotov SN, Kushin VV
Radiat Environ Biophys · 2023 Aug · PMID 37355532 · Publisher ↗
The field of cosmic radiation at low-Earth orbit (LEO) has a complex composition. It always contains a component of secondary charged particles, formed by the products of nuclear interactions of the primary high-energy r...
The field of cosmic radiation at low-Earth orbit (LEO) has a complex composition. It always contains a component of secondary charged particles, formed by the products of nuclear interactions of the primary high-energy radiation with the nuclei of spacecraft's shielding material, electronic components and biological matter on board. Generation of this secondary radiation can be observed in some track detectors in the form of "stars" formed by tracks-fragments with a common vertex. The energy absorbed by the medium in the region adjacent to the interaction vertex can reach abnormally high values because of its intersection by several particle fragments. In the present paper, a methodology is considered to calculate the energy imparted by such fragments to a spherical sensitive volume in an aqueous medium. The energy distributions for three fragment events were calculated for different positions of the vertex relative to the spherical volume. The obtained data were analyzed and were compared with the distribution for a uniform fluence of secondary particles. It was shown that as the fragmentation vertex approaches the boundary of the sensitive micro-volume, the probability of events with anomalously high energy transfers, higher than the energies from single fragments, increases. The method can be applied to calculate absorbed energy distributions from secondary radiation in media of different elemental composition than that used in the present work. In the future, it is of interest to apply the method for example to study the energy imparted from secondary fragments to a silicon medium, to quantify the number of single event upsets in electronic components.
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