Pub Date : 2025-02-01Epub Date: 2024-12-05DOI: 10.1016/j.radmp.2024.12.001
Jiayu Liu, Xiaojun Lu, Chao Zhao
Objective
To assess the detection efficiencies of liquid radioisotopes in a well-type NaI(Tl) gamma spectrometer, focusing on the short-lived isotopes 99Tcm, 131I, and 18F.
Methods
The detection efficiencies of liquid 99Tcm, 131I, and 18F in a well-type NaI(Tl) gamma spectrometer were systematically investigated through calibration experiments and Monte Carlo simulations, and accounting for the coincidence-summing effect.
Results
The results indicated that the detection efficiencies of 99Tcm, 131I, and 18F varied from 64.4% to 72.3%, 34.8%–43.1% and 27.3%–28.5% for different sample volumes ranging from 15 mL to 80 mL, respectively. The simulated detection efficiencies were highly consistent with the experimental results, with a largest relative deviation of 5% for the 3 radionuclides and 4 different sample volumes.
Conclusion
The consistent results between the calibration experiments and Monte Carlo simulations reveal that this measuring device possesses high detection efficiencies of 99Tcm, 131I, and 18F, making it suitable for measuring low-level activity radioactive liquids, such as radioactive waste liquids to be discharged.
{"title":"Study on the detection efficiencies of liquid 99Tcm, 131I, and 18F in a well-type NaI(Tl) gamma spectrometer","authors":"Jiayu Liu, Xiaojun Lu, Chao Zhao","doi":"10.1016/j.radmp.2024.12.001","DOIUrl":"10.1016/j.radmp.2024.12.001","url":null,"abstract":"<div><h3>Objective</h3><div>To assess the detection efficiencies of liquid radioisotopes in a well-type NaI(Tl) gamma spectrometer, focusing on the short-lived isotopes <sup>99</sup>Tc<sup>m</sup>, <sup>131</sup>I, and <sup>18</sup>F.</div></div><div><h3>Methods</h3><div>The detection efficiencies of liquid <sup>99</sup>Tc<sup>m</sup>, <sup>131</sup>I, and <sup>18</sup>F in a well-type NaI(Tl) gamma spectrometer were systematically investigated through calibration experiments and Monte Carlo simulations, and accounting for the coincidence-summing effect.</div></div><div><h3>Results</h3><div>The results indicated that the detection efficiencies of <sup>99</sup>Tc<sup>m</sup>, <sup>131</sup>I, and <sup>18</sup>F varied from 64.4% to 72.3%, 34.8%–43.1% and 27.3%–28.5% for different sample volumes ranging from 15 mL to 80 mL, respectively. The simulated detection efficiencies were highly consistent with the experimental results, with a largest relative deviation of 5% for the 3 radionuclides and 4 different sample volumes.</div></div><div><h3>Conclusion</h3><div>The consistent results between the calibration experiments and Monte Carlo simulations reveal that this measuring device possesses high detection efficiencies of <sup>99</sup>Tc<sup>m</sup>, <sup>131</sup>I, and <sup>18</sup>F, making it suitable for measuring low-level activity radioactive liquids, such as radioactive waste liquids to be discharged.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 46-50"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01Epub Date: 2024-10-21DOI: 10.1016/j.radmp.2024.10.004
Tomas Palmqvist , Milagrosa Lopez-Riego , Martin Bucher , Ursula Oestreicher , Stefan Pojtinger , Ulrich Giesen , Iuliana Toma-Dasu , Andrzej Wojcik
Objective
To investigate the potential impact of two different combinations of neutron and gamma radiation on gene expression and dicentric chromosomes in peripheral blood mononuclear cells (PBMC).
Methods
Whole blood from 3 human donors was exposed to neutrons with an energy spectrum similar to that of the Hiroshima uranium bomb, to gamma radiation from a 60Co source and to a 50:50 combination of both radiations, given in two orders of sequence. In all cases the total doses were 0.5, 0.75 and 1.0 Gy. Dicentric chromosomes were analyzed by light microscopy and the expression of six known radiation-responsive genes BBC3, CDKN1A, FDXR, GADD45A, MDM2, and XPC were analyzed by RT-qPCR.
Results
Per unit dose, exposure to neutrons lead to a higher level of dicentrics and gene expression as compared to gamma radiation. Dose-response relationships for both endpoints were linear, allowing calculating the expected outcome of combined exposure by arithmetic. For dicentric chromosomes, the RBE values for 60Co → neutrons, neutrons → 60Co and neutrons were 4.05, 3.62 and 7.30, respectively. For gene expression the RBE values were gene-specific, but showed values in the range of 1.14–3.01 for 60Co → neutrons, 1.33–2.68 for neutrons → 60Co and 1.39–3.91 for neutrons.
Conclusions
The results demonstrate that combined exposure to neutrons and gamma radiation, regardless of the order of sequence, leads to an additive response at both endpoints. This indicates that calibration curves for mixed beams can be constructed from dose response relationships of the single beam components.
{"title":"Biological effectiveness of combined exposure to neutrons and gamma radiation applied in two orders of sequence: Relevance for biological dosimetry after nuclear emergencies","authors":"Tomas Palmqvist , Milagrosa Lopez-Riego , Martin Bucher , Ursula Oestreicher , Stefan Pojtinger , Ulrich Giesen , Iuliana Toma-Dasu , Andrzej Wojcik","doi":"10.1016/j.radmp.2024.10.004","DOIUrl":"10.1016/j.radmp.2024.10.004","url":null,"abstract":"<div><h3>Objective</h3><div>To investigate the potential impact of two different combinations of neutron and gamma radiation on gene expression and dicentric chromosomes in peripheral blood mononuclear cells (PBMC).</div></div><div><h3>Methods</h3><div>Whole blood from 3 human donors was exposed to neutrons with an energy spectrum similar to that of the Hiroshima uranium bomb, to gamma radiation from a <sup>60</sup>Co source and to a 50:50 combination of both radiations, given in two orders of sequence. In all cases the total doses were 0.5, 0.75 and 1.0 Gy. Dicentric chromosomes were analyzed by light microscopy and the expression of six known radiation-responsive genes BBC3, CDKN1A, FDXR, GADD45A, MDM2, and XPC were analyzed by RT-qPCR.</div></div><div><h3>Results</h3><div>Per unit dose, exposure to neutrons lead to a higher level of dicentrics and gene expression as compared to gamma radiation. Dose-response relationships for both endpoints were linear, allowing calculating the expected outcome of combined exposure by arithmetic. For dicentric chromosomes, the RBE values for <sup>60</sup>Co → neutrons, neutrons → <sup>60</sup>Co and neutrons were 4.05, 3.62 and 7.30, respectively. For gene expression the RBE values were gene-specific, but showed values in the range of 1.14–3.01 for <sup>60</sup>Co → neutrons, 1.33–2.68 for neutrons → <sup>60</sup>Co and 1.39–3.91 for neutrons.</div></div><div><h3>Conclusions</h3><div>The results demonstrate that combined exposure to neutrons and gamma radiation, regardless of the order of sequence, leads to an additive response at both endpoints. This indicates that calibration curves for mixed beams can be constructed from dose response relationships of the single beam components.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 1-10"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01Epub Date: 2024-12-06DOI: 10.1016/j.radmp.2024.12.002
Qiuhua Zhou , Yiquan Ou , Xiangsheng Tian , Yujun Ning , Yuwei Mao , Weichao Zhao , Dingxin Long
Objective
To investigate whether Ginsenoside Rg1 can mitigate the adverse effects of cranial irradiation on distal reproductive function in mice and to explore the underlying mechanisms.
Methods
Forty male C57BL/6J mice were randomly divided to four groups [Control, irradiation (IR), IR + Rg1, Rg1), IR + Rg1 and Rg1 group treated with intraperitoneal injections of Ginsenoside Rg1 for 30 d, followed by single-dose irradiation of 5 Gy X-ray irradiation (2 Gy/min) for the IR and IR + Rg1 group. After three months, testicles, whole brain, and serum samples were collected for analysis.
Results
Histological staining, transmission electron microscopy, sperm analysis, and immunofluorescence demonstrated that Ginsenoside Rg1 ameliorated structural and functional damage to the testicles, enhanced sperm count (IR: 20.70 ± 1.62 vs. IR + Rg1: 33.93 ± 2.20, t = −13.23, P < 0.05), and reduced sperm malformation rates (IR: 46.33 ± 2.18 vs. IR + Rg1: 39.00 ± 1.67, t = 7.33, P < 0.05). Further Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) and Enzyme linked immunosorbent assay (ELISA) assays demonstrated that Rg1 inhibited testicular apoptosis (IR: 3.21 ± 0.28 vs. IR + Rg1: 1.81 ± 0.18, t = 1.40, P < 0.05) and modulated serum testosterone (IR: 4.47 ± 0.23 vs. IR + Rg1: 6.65 ± 0.09, t = −2.18, P < 0.05), GnRH (IR: 24.37 ± 0.92 vs. IR + Rg1: 32.98 ± 1.33, t = −8.61, P < 0.05), and FSH levels (IR: 1.41 ± 0.11 vs. IR + Rg1: 2.69 ± 0.21, t = −1.28, P < 0.05). Additionally, quantitative PCR and Western blot showed that Rg1 downregulated SCF, p-PI3K, p-Akt, and mTOR protein expressions in irradiated mice.
Conclusions
Ginsenoside Rg1 potentially alleviate chronic testicular structural and functional damage by inhibiting germ cell apoptosis through the modulation of the HPG axis and the PI3K/Akt/mTOR pathway, suggesting that it is a potential therapeutic agent for reproductive disorders induced by cranial irradiation.
目的研究人参皂苷Rg1是否能减轻颅照射对小鼠远端生殖功能的不良影响，并探讨其机制。方法雄性C57BL/6J小鼠40只，随机分为4组[对照组、辐照（IR）、IR + Rg1、Rg1)、IR + Rg1、Rg1组]，腹腔注射人参皂苷Rg1治疗30 d， IR组和IR + Rg1组均给予5 Gy x射线单剂量照射（2 Gy/min）。三个月后，收集睾丸、全脑和血清样本进行分析。结果组织学染色、透射电镜、精子分析和免疫荧光显示，人参皂苷Rg1改善了睾丸结构和功能损伤，提高了精子数量(IR: 20.70±1.62 vs. IR + Rg1: 33.93±2.20,t =−13.23,P <；0.05),并降低精子畸形率(红外:46.33±2.18与红外+ Rg1: 39.00±1.67,t = 7.33, P & lt;0.05)。进一步的末端脱氧核苷酸转移酶介导的dutp -生物素缺口末端标记（TUNEL）和酶联免疫吸附试验（ELISA）表明，Rg1抑制睾丸细胞凋亡(IR: 3.21±0.28 vs. IR + Rg1: 1.81±0.18,t = 1.40, P <；0.05)和调制血清睾酮(红外:4.47±0.23与红外+ Rg1: 6.65±0.09,t =−2.18,P & lt;激性腺素释放素(0.05),红外:24.37±0.92与红外+ Rg1: 32.98±1.33,t =−8.61,P & lt;0.05),和FSH水平(红外:1.41±0.11与红外+ Rg1: 2.69±0.21,t =−1.28,P & lt;0.05)。此外，定量PCR和Western blot结果显示，Rg1下调了辐照小鼠SCF、p-PI3K、p-Akt和mTOR蛋白的表达。结论人参皂苷Rg1可能通过调控HPG轴和PI3K/Akt/mTOR通路抑制生殖细胞凋亡，从而减轻慢性睾丸结构和功能损伤，提示人参皂苷Rg1可能是治疗颅脑照射所致生殖障碍的潜在药物。
{"title":"Ginsenoside Rg1 alleviates chronic testicular damage caused by cranial irradiation through the SCF/PI3K/Akt/mTOR pathway in mice","authors":"Qiuhua Zhou , Yiquan Ou , Xiangsheng Tian , Yujun Ning , Yuwei Mao , Weichao Zhao , Dingxin Long","doi":"10.1016/j.radmp.2024.12.002","DOIUrl":"10.1016/j.radmp.2024.12.002","url":null,"abstract":"<div><h3>Objective</h3><div>To investigate whether Ginsenoside Rg1 can mitigate the adverse effects of cranial irradiation on distal reproductive function in mice and to explore the underlying mechanisms.</div></div><div><h3>Methods</h3><div>Forty male C57BL/6J mice were randomly divided to four groups [Control, irradiation (IR), IR + Rg1, Rg1), IR + Rg1 and Rg1 group treated with intraperitoneal injections of Ginsenoside Rg1 for 30 d, followed by single-dose irradiation of 5 Gy X-ray irradiation (2 Gy/min) for the IR and IR + Rg1 group. After three months, testicles, whole brain, and serum samples were collected for analysis.</div></div><div><h3>Results</h3><div>Histological staining, transmission electron microscopy, sperm analysis, and immunofluorescence demonstrated that Ginsenoside Rg1 ameliorated structural and functional damage to the testicles, enhanced sperm count (IR: 20.70 ± 1.62 <em>vs.</em> IR + Rg1: 33.93 ± 2.20, <em>t</em> = −13.23, <em>P</em> < 0.05), and reduced sperm malformation rates (IR: 46.33 ± 2.18 <em>vs.</em> IR + Rg1: 39.00 ± 1.67, <em>t</em> = 7.33, <em>P</em> < 0.05). Further Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) and Enzyme linked immunosorbent assay (ELISA) assays demonstrated that Rg1 inhibited testicular apoptosis (IR: 3.21 ± 0.28 <em>vs.</em> IR + Rg1: 1.81 ± 0.18, <em>t</em> = 1.40, <em>P</em> < 0.05) and modulated serum testosterone (IR: 4.47 ± 0.23 <em>vs.</em> IR + Rg1: 6.65 ± 0.09, <em>t</em> = −2.18, <em>P</em> < 0.05), GnRH (IR: 24.37 ± 0.92 <em>vs.</em> IR + Rg1: 32.98 ± 1.33, <em>t</em> = −8.61, <em>P</em> < 0.05), and FSH levels (IR: 1.41 ± 0.11 <em>vs.</em> IR + Rg1: 2.69 ± 0.21, <em>t</em> = −1.28, <em>P</em> < 0.05). Additionally, quantitative PCR and Western blot showed that Rg1 downregulated SCF, p-PI3K, p-Akt, and mTOR protein expressions in irradiated mice.</div></div><div><h3>Conclusions</h3><div>Ginsenoside Rg1 potentially alleviate chronic testicular structural and functional damage by inhibiting germ cell apoptosis through the modulation of the HPG axis and the PI3K/Akt/mTOR pathway, suggesting that it is a potential therapeutic agent for reproductive disorders induced by cranial irradiation.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 11-21"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01Epub Date: 2024-08-28DOI: 10.1016/j.radmp.2024.08.002
Bei Yu , Fei Chen , Jing Cao , Dingxin Long
Objective
To monitor the radioactivity concentration of 14C in the air of rooms used to perform 14C urea breath tests, and evaluate the contamination status of 14C released during such tests, and assess the occupational health risk to medical staff working in such areas.
Methods
14CO2 in air was absorbed from the air and turned into calcium carbonate through a chemical reaction. Then, calcium carbonate was prepared into a suspension in a low-potassium glass vial. The sample was analyzed using a low-background liquid scintillation counter.
Results
The radioactivity concentrations of 14C in air of the breath-test rooms in hospitals and physical examination institutions range from 1.35 to 18.41 Bq/m3. The annual committed dose for medical staff was estimated to be between 2.01 × 10−2 and 2.74 × 10−1 μSv.
Conclusions
Our results reveal a significant increase of 14C radioactivity concentration in the air of breath-test rooms, but the resulting committed dose is much lower than the limits prescribed by the International Commission on Radiological Protection (ICRP). However, the potential risk of long-term exposure to low-dose radiation should be paid more attention.
{"title":"Radioactivity concentration of 14C in the air of 14C urea breath test rooms and the resulting internal dose to medical staff","authors":"Bei Yu , Fei Chen , Jing Cao , Dingxin Long","doi":"10.1016/j.radmp.2024.08.002","DOIUrl":"10.1016/j.radmp.2024.08.002","url":null,"abstract":"<div><h3>Objective</h3><div>To monitor the radioactivity concentration of <sup>14</sup>C in the air of rooms used to perform <sup>14</sup>C urea breath tests, and evaluate the contamination status of <sup>14</sup>C released during such tests, and assess the occupational health risk to medical staff working in such areas.</div></div><div><h3>Methods</h3><div><sup>14</sup>CO<sub>2</sub> in air was absorbed from the air and turned into calcium carbonate through a chemical reaction. Then, calcium carbonate was prepared into a suspension in a low-potassium glass vial. The sample was analyzed using a low-background liquid scintillation counter.</div></div><div><h3>Results</h3><div>The radioactivity concentrations of <sup>14</sup>C in air of the breath-test rooms in hospitals and physical examination institutions range from 1.35 to 18.41 Bq/m<sup>3</sup>. The annual committed dose for medical staff was estimated to be between 2.01 × 10<sup>−2</sup> and 2.74 × 10<sup>−1</sup> μSv.</div></div><div><h3>Conclusions</h3><div>Our results reveal a significant increase of <sup>14</sup>C radioactivity concentration in the air of breath-test rooms, but the resulting committed dose is much lower than the limits prescribed by the International Commission on Radiological Protection (ICRP). However, the potential risk of long-term exposure to low-dose radiation should be paid more attention.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 43-45"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01Epub Date: 2024-10-18DOI: 10.1016/j.radmp.2024.10.003
Kapil Dev Maharaj , Mahsheed Sabet , Joshua Dass , Mounir Ibrahim , Talat Mahmood , Pejman Rowshanfarzad
Objective
To investigate the characteristics of peripheral doses outside electron-beam applicators in Varian TrueBeam linacs.
Method
Peripheral doses outside the electron applicator were measured for 6-, 9- and 12-MeV beams at the maximum dose depth (Dmax) for each energy source and at a source-to-surface distance (SSD) of 100 cm. Measurements were performed using EBT3 films in solid water phantoms. The impact of field size on the penumbra width and peripheral doses was studied using various cutouts, including 3 cm × 3 cm, 6 cm × 6 cm, and 10 cm × 10 cm in a 10 cm × 10 cm applicator with the gantry and collimator at 0°. The influence of the applicator size was investigated using a circular cutout of 5 cm in diameter for various applicator sizes, including 6 cm × 6 cm, 10 cm × 10 cm, 15 cm × 15 cm, 20 cm × 20 cm, and 25 cm × 25 cm, at Dmax for each energy, while keeping the gantry and collimator angle at 0°. The measured dose profiles were compared with the Eclipse treatment planning system (TPS) predicted dose profiles. The effect of varying gantry angles (0°, 90°, and 270°) for a 3 cm × 3 cm cutout in a 10 cm × 10 cm applicator for each energy source and varying collimator angles (0°, 90°, and 270°) for a 10 cm × 10 cm field were investigated to determine their effects on the penumbra widths and peripheral doses.
Results
Both the penumbra width and peripheral dose values increased with energy across different field sizes, gantry angles, collimator angles, and applicator sizes. Root mean square deviation (RMSD) analysis indicated minimal differences between the measured profiles and TPS data. Peripheral doses remained below 5% of the maximum dose approximately 10–15 mm away from the field edges, suggesting the potential for implementing additional shielding where required.
Conclusions
This study highlights the importance of considering peripheral doses in electron radiotherapy. It is important to note the impact on healthy tissues beyond the treatment area to ensure patient safety and prevent the long-term side effects of treatment. These findings emphasize the necessity of implementing appropriate measures to minimize peripheral doses.
目的探讨瓦里安TrueBeam直线加速器电子束外周剂量的特点。方法在每个能量源的最大剂量深度（Dmax）和源-表面距离（SSD）为100 cm时，测量6、9和12 mev束流在电子施加器外的外周剂量。使用EBT3薄膜在固体水模型中进行测量。在10 cm × 10 cm施药器中，使用不同的切口，包括3 cm × 3 cm、6 cm × 6 cm和10 cm × 10 cm，研究了视场尺寸对半影宽度和外围剂量的影响。使用直径为5 cm的圆形切口，研究了不同尺寸的涂药器（包括6 cm × 6 cm、10 cm × 10 cm、15 cm × 15 cm、20 cm × 20 cm和25 cm × 25 cm）在每种能量的Dmax下对涂药器尺寸的影响，同时保持机架和准直器角度为0°。测量剂量谱与Eclipse治疗计划系统（TPS）预测剂量谱进行比较。研究了不同的门架角度（0°，90°和270°）对每个能量源在10 cm × 10 cm应用器中3cm × 3cm切口的影响，以及不同的准直角度（0°，90°和270°）对10 cm × 10 cm场的影响，以确定它们对半影宽度和外围剂量的影响。结果在不同视场尺寸、门架角度、准直器角度和施药器尺寸下，半影宽度和周边剂量值均随能量的增加而增加。均方根偏差（RMSD）分析表明，测量剖面与TPS数据之间的差异极小。外围剂量保持在最大剂量的5%以下，距离场边约10-15毫米，表明有可能在需要时实施额外的屏蔽。结论本研究强调了在电子放射治疗中考虑外周剂量的重要性。重要的是要注意对治疗区域以外的健康组织的影响，以确保患者安全并防止治疗的长期副作用。这些发现强调了采取适当措施尽量减少周边剂量的必要性。
{"title":"Comprehensive analysis of peripheral dose in electron beam therapy with a Varian TrueBeam Linac","authors":"Kapil Dev Maharaj , Mahsheed Sabet , Joshua Dass , Mounir Ibrahim , Talat Mahmood , Pejman Rowshanfarzad","doi":"10.1016/j.radmp.2024.10.003","DOIUrl":"10.1016/j.radmp.2024.10.003","url":null,"abstract":"<div><h3>Objective</h3><div>To investigate the characteristics of peripheral doses outside electron-beam applicators in Varian TrueBeam linacs.</div></div><div><h3>Method</h3><div>Peripheral doses outside the electron applicator were measured for 6-, 9- and 12-MeV beams at the maximum dose depth (<em>D</em><sub>max</sub>) for each energy source and at a source-to-surface distance (SSD) of 100 cm. Measurements were performed using EBT3 films in solid water phantoms. The impact of field size on the penumbra width and peripheral doses was studied using various cutouts, including 3 cm × 3 cm, 6 cm × 6 cm, and 10 cm × 10 cm in a 10 cm × 10 cm applicator with the gantry and collimator at 0°. The influence of the applicator size was investigated using a circular cutout of 5 cm in diameter for various applicator sizes, including 6 cm × 6 cm, 10 cm × 10 cm, 15 cm × 15 cm, 20 cm × 20 cm, and 25 cm × 25 cm, at <em>D</em><sub>max</sub> for each energy, while keeping the gantry and collimator angle at 0°. The measured dose profiles were compared with the Eclipse treatment planning system (TPS) predicted dose profiles. The effect of varying gantry angles (0°, 90°, and 270°) for a 3 cm × 3 cm cutout in a 10 cm × 10 cm applicator for each energy source and varying collimator angles (0°, 90°, and 270°) for a 10 cm × 10 cm field were investigated to determine their effects on the penumbra widths and peripheral doses.</div></div><div><h3>Results</h3><div>Both the penumbra width and peripheral dose values increased with energy across different field sizes, gantry angles, collimator angles, and applicator sizes. Root mean square deviation (RMSD) analysis indicated minimal differences between the measured profiles and TPS data. Peripheral doses remained below 5% of the maximum dose approximately 10–15 mm away from the field edges, suggesting the potential for implementing additional shielding where required.</div></div><div><h3>Conclusions</h3><div>This study highlights the importance of considering peripheral doses in electron radiotherapy. It is important to note the impact on healthy tissues beyond the treatment area to ensure patient safety and prevent the long-term side effects of treatment. These findings emphasize the necessity of implementing appropriate measures to minimize peripheral doses.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 28-36"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To evaluate the dosimetric quality of radiotherapy plans for nasopharyngeal carcinoma (NPC) using HyperArc (HA) technology.
Methods
A retrospective analysis was conducted on 20 patients with initially diagnosed NPC who had received TomoTherapy (TOMO) treatment. Treatment plans were redesigned using HA technology on the Eclipse planning system. Dosimetric parameters and verification passing rates were collected to assess the dosimetric quality of target coverage and organ-at-risk (OAR) sparing in both sets of plans. Paired t-tests or Rank-Sum tests were used to compare the dosimetric parameters between the two plans.
Results
For the planning target volumes (PTVs), the target coverage in both plans reached 95%. Compared with the TOMO plans, the HA plans exhibited a steeper dose fall-off for PTV69.75Gy (P < 0.05). However, the conformity index (CI) of the HA plans (0.75) was slightly lower than that of the TOMO plans (0.81, P < 0.05). The homogeneity index (HI) was better in the TOMO plans, with statistically significant differences for PTV69.75Gy and PTV55.80Gy (P < 0.05). Moreover, the HA plans had better sparing, particularly for the optic chiasm, optic nerves, and parotid glands (P < 0.05), while no statistically significant differences were observed for other critical structures such as the brainstem, spinal cord, and temporal lobes (P > 0.05). Additionally, the average beam-on time for the HA plans (252 s) was shorter than that of the TOMO plans (326 s, P < 0.05). The mean gamma passing rate at 3%/2 mm for all plans exceeded 98%.
Conclusions
Radiotherapy plans for NPC based on HA technology exhibit excellent dosimetric quality, providing good target coverage, rapid dose fall-off, and effective protection of adjacent critical organs.
{"title":"Dosimetry of automatic non-coplanar volumetric-modulated arc therapy for nasopharyngeal carcinoma","authors":"Kaiqiang Chen, Jihong Chen, Yanming Cheng, Danni Hong, Cairong Hu, Penggang Bai, Jinyong Lin, Yang Yang, Xiuchun Zhang","doi":"10.1016/j.radmp.2024.12.004","DOIUrl":"10.1016/j.radmp.2024.12.004","url":null,"abstract":"<div><h3>Objective</h3><div>To evaluate the dosimetric quality of radiotherapy plans for nasopharyngeal carcinoma (NPC) using HyperArc (HA) technology.</div></div><div><h3>Methods</h3><div>A retrospective analysis was conducted on 20 patients with initially diagnosed NPC who had received TomoTherapy (TOMO) treatment. Treatment plans were redesigned using HA technology on the Eclipse planning system. Dosimetric parameters and verification passing rates were collected to assess the dosimetric quality of target coverage and organ-at-risk (OAR) sparing in both sets of plans. Paired <em>t</em>-tests or Rank-Sum tests were used to compare the dosimetric parameters between the two plans.</div></div><div><h3>Results</h3><div>For the planning target volumes (PTVs), the target coverage in both plans reached 95%. Compared with the TOMO plans, the HA plans exhibited a steeper dose fall-off for PTV<sub>69.75Gy</sub> (<em>P</em> < 0.05). However, the conformity index (CI) of the HA plans (0.75) was slightly lower than that of the TOMO plans (0.81, <em>P</em> <em><</em> 0.05). The homogeneity index (HI) was better in the TOMO plans, with statistically significant differences for PTV<sub>69.75Gy</sub> and PTV<sub>55.80Gy</sub> (<em>P</em> < 0.05). Moreover, the HA plans had better sparing, particularly for the optic chiasm, optic nerves, and parotid glands (<em>P</em> < 0.05), while no statistically significant differences were observed for other critical structures such as the brainstem, spinal cord, and temporal lobes (<em>P</em> > 0.05). Additionally, the average beam-on time for the HA plans (252 s) was shorter than that of the TOMO plans (326 s, <em>P</em> < 0.05). The mean gamma passing rate at 3%/2 mm for all plans exceeded 98%.</div></div><div><h3>Conclusions</h3><div>Radiotherapy plans for NPC based on HA technology exhibit excellent dosimetric quality, providing good target coverage, rapid dose fall-off, and effective protection of adjacent critical organs.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 37-42"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-01Epub Date: 2024-11-28DOI: 10.1016/j.radmp.2024.11.002
Ying Xu, Wentao Hu, Guangming Zhou
Heat shock protein (HSP), as an intracellular chaperone, is significantly upregulated when cells are exposed to radiation and other stress environments, playing an important role in cell self-protection. This phenomenon not only provides a mechanism for normal tissues to resist radiation damage, but also provides a strategy for cancer cells to reduce their sensitivity to radiation and escape treatment. More research is needed to clarify the specific mechanism of HSP in radiotherapy and how to better use its biological effects for clinical individualized treatment. This paper reviews the biological effects of HSP under radiation and the latest research progress of combined radiation and HSP inhibitors or hyperthermia, in the hope of having a more comprehensive understanding of its mechanism in physiological processes such as cell survival, apoptosis, inflammation, immune response, as well as radiation response, which will help to enhance the therapeutic effect and to provide more effective and safer radiotherapy for cancer patients in the future.
{"title":"Role of heat shock protein in radiation-induced effect and related potential clinical application","authors":"Ying Xu, Wentao Hu, Guangming Zhou","doi":"10.1016/j.radmp.2024.11.002","DOIUrl":"10.1016/j.radmp.2024.11.002","url":null,"abstract":"<div><div>Heat shock protein (HSP), as an intracellular chaperone, is significantly upregulated when cells are exposed to radiation and other stress environments, playing an important role in cell self-protection. This phenomenon not only provides a mechanism for normal tissues to resist radiation damage, but also provides a strategy for cancer cells to reduce their sensitivity to radiation and escape treatment. More research is needed to clarify the specific mechanism of HSP in radiotherapy and how to better use its biological effects for clinical individualized treatment. This paper reviews the biological effects of HSP under radiation and the latest research progress of combined radiation and HSP inhibitors or hyperthermia, in the hope of having a more comprehensive understanding of its mechanism in physiological processes such as cell survival, apoptosis, inflammation, immune response, as well as radiation response, which will help to enhance the therapeutic effect and to provide more effective and safer radiotherapy for cancer patients in the future.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"6 1","pages":"Pages 51-60"},"PeriodicalIF":0.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-01Epub Date: 2024-07-29DOI: 10.1016/j.radmp.2024.07.001
Radiation Oncology Physician Branch, Chinese Medical Doctor Association , Radiation Oncology Branch, Chinese Medical Association, Professional Commitee of Radiation Oncology, China Anti-Cancer Association, Expert Committee of Esophageal Cancer, Chinese Cancer Radiotherapy Alliance, Radiotherapy Sub-Committee, Professional Commitee of Elderly Oncology, Gerontological Society of China
China exhibits a high incidence of esophageal cancer. In the context of rapid population aging, esophageal cancer has become a significant threat to the health of Chinese elderly population. Currently, there is a lack of a clear definition or assessment method for esophageal cancer in elderly patients, and this population is frequently excluded in clinical trials. Consequently, high-level evidence and global consensus guidelines for the treatment of this population are unavailable. Since elderly patients with esophageal cancer cannot tolerate surgery and intensive chemotherapy, radiotherapy plays a vital role in their treatment. Based on recent research data on esophageal cancer in elderly patients, the expert consensus on radiotherapy for esophageal cancer in elderly patients in China was jointly developed by experts from the following organizations: Radiation Oncology Physician Branch, Chinese Medical Doctor Association; Radiation Oncology Branch, Chinese Medical Association; Professional Committee of Radiation Oncology, China Anti-Cancer Association; Expert Committee of Esophageal Cancer, Chinese Cancer Radiotherapy Alliance; Radiotherapy Sub-Committee, Professional Committee of Elderly Oncology, Gerontological Society of China. This consensus defines esophageal cancer in elderly patients, emphasizes the importance of nutritional assessment and intervention, and elaborates on the mode of radiotherapy alone and radiotherapy-based combined modality therapy mode. Moreover, this consensus organizes radiotherapy technology, radiation dose, and safety management, aiming to provide a foundational guide for clinical practice targeting esophageal cancer in elderly patients.
{"title":"Expert consensus on radiotherapy for elderly patients with esophageal cancer in China (2024 edition)","authors":"Radiation Oncology Physician Branch, Chinese Medical Doctor Association , Radiation Oncology Branch, Chinese Medical Association, Professional Commitee of Radiation Oncology, China Anti-Cancer Association, Expert Committee of Esophageal Cancer, Chinese Cancer Radiotherapy Alliance, Radiotherapy Sub-Committee, Professional Commitee of Elderly Oncology, Gerontological Society of China","doi":"10.1016/j.radmp.2024.07.001","DOIUrl":"10.1016/j.radmp.2024.07.001","url":null,"abstract":"<div><div>China exhibits a high incidence of esophageal cancer. In the context of rapid population aging, esophageal cancer has become a significant threat to the health of Chinese elderly population. Currently, there is a lack of a clear definition or assessment method for esophageal cancer in elderly patients, and this population is frequently excluded in clinical trials. Consequently, high-level evidence and global consensus guidelines for the treatment of this population are unavailable. Since elderly patients with esophageal cancer cannot tolerate surgery and intensive chemotherapy, radiotherapy plays a vital role in their treatment. Based on recent research data on esophageal cancer in elderly patients, the expert consensus on radiotherapy for esophageal cancer in elderly patients in China was jointly developed by experts from the following organizations: Radiation Oncology Physician Branch, Chinese Medical Doctor Association; Radiation Oncology Branch, Chinese Medical Association; Professional Committee of Radiation Oncology, China Anti-Cancer Association; Expert Committee of Esophageal Cancer, Chinese Cancer Radiotherapy Alliance; Radiotherapy Sub-Committee, Professional Committee of Elderly Oncology, Gerontological Society of China. This consensus defines esophageal cancer in elderly patients, emphasizes the importance of nutritional assessment and intervention, and elaborates on the mode of radiotherapy alone and radiotherapy-based combined modality therapy mode. Moreover, this consensus organizes radiotherapy technology, radiation dose, and safety management, aiming to provide a foundational guide for clinical practice targeting esophageal cancer in elderly patients.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"5 4","pages":"Pages 268-275"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143174401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-01Epub Date: 2024-10-22DOI: 10.1016/j.radmp.2024.10.005
Weihai Zhuo, Qiuju Guo, Quanfu Sun
{"title":"Research needs, measurements and behaviours of environmental radon","authors":"Weihai Zhuo, Qiuju Guo, Quanfu Sun","doi":"10.1016/j.radmp.2024.10.005","DOIUrl":"10.1016/j.radmp.2024.10.005","url":null,"abstract":"","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"5 4","pages":"Pages 213-214"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143174399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-01Epub Date: 2024-09-01DOI: 10.1016/j.radmp.2024.08.003
Zsolt Homoki, Gergely Tóth, Anita Csordás, Edit Tóth-Bodrogi, Miklós Hegedűs, Tibor Kovács
Objective
To investigate the current levels of indoor radon activity in the geologically complex Bakony Region of Hungary, which has been historically affected by industrial activities, and to identify areas that may require further monitoring and intervention.
Methods
Experiments were carried out to measure quarterly indoor radon activity concentrations in ground-floor dwellings for a year using CR-39-type nuclear track detectors at 30 locations in 9 settlements to provide current information on the Bakony Region and identify areas requiring further attention.
Results
Since the annual average indoor radon activity concentration in the Bakony Region was 86 Bq/m3 and the maximum 274 Bq/m3, that is, less than the 300 Bq/m3 national and EU reference levels, it is considered safe. Two locations were equal to or exceeded the reference level during part of the year. While most of the Region exhibited high radon concentrations in the autumn and winter, two settlements presented inverse seasonal variations.
Conclusion
Although the autumn and winter values yielded a strong correlation with the annual mean and each other, this was not the case regarding the summer and spring values. The annual mean effective dose for the Region from the inhalation of radon and its progenies was estimated to be 2.2 mSv/year.
{"title":"Assessment of the residential radon concentrations in the Bakony Region, Hungary","authors":"Zsolt Homoki, Gergely Tóth, Anita Csordás, Edit Tóth-Bodrogi, Miklós Hegedűs, Tibor Kovács","doi":"10.1016/j.radmp.2024.08.003","DOIUrl":"10.1016/j.radmp.2024.08.003","url":null,"abstract":"<div><h3>Objective</h3><div>To investigate the current levels of indoor radon activity in the geologically complex Bakony Region of Hungary, which has been historically affected by industrial activities, and to identify areas that may require further monitoring and intervention.</div></div><div><h3>Methods</h3><div>Experiments were carried out to measure quarterly indoor radon activity concentrations in ground-floor dwellings for a year using CR-39-type nuclear track detectors at 30 locations in 9 settlements to provide current information on the Bakony Region and identify areas requiring further attention.</div></div><div><h3>Results</h3><div>Since the annual average indoor radon activity concentration in the Bakony Region was 86 Bq/m<sup>3</sup> and the maximum 274 Bq/m<sup>3</sup>, that is, less than the 300 Bq/m<sup>3</sup> national and EU reference levels, it is considered safe. Two locations were equal to or exceeded the reference level during part of the year. While most of the Region exhibited high radon concentrations in the autumn and winter, two settlements presented inverse seasonal variations.</div></div><div><h3>Conclusion</h3><div>Although the autumn and winter values yielded a strong correlation with the annual mean and each other, this was not the case regarding the summer and spring values. The annual mean effective dose for the Region from the inhalation of radon and its progenies was estimated to be 2.2 mSv/year.</div></div>","PeriodicalId":34051,"journal":{"name":"Radiation Medicine and Protection","volume":"5 4","pages":"Pages 243-247"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143175749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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