Department of Radiation Oncology, The University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA.
Department of Radiation Oncology, The University of Texas Health Science Center at San Antonio, San Antonio, TX, 78229, USA.
Appl Radiat Isot. 2020 Nov;165:109316. doi: 10.1016/j.apradiso.2020.109316. Epub 2020 Jul 15.
A DNA dosimeter (DNAd) was previously developed that uses double-strand breaks (DSB) to measure dose. This dosimeter has been tested to measure dose in scenarios where transient-charged particle equilibrium (TCPE) has been established. The probability of double strand break (PDSB), which is the ratio of broken double-stranded DNA (dsDNA) to the initial unbroken dsDNA in the dosimeter, was used to quantify DSBs and related to dose. The goal of this work is to produce a new technique to process and analyze the DNAd and quantify DNA-DSBs. This technique included simultaneously processing multiple DNAds and also establishing a new form to the probability of double strand break (PDSB), which was then used to test the DNAd in a non-TCPE condition by taking beam penumbra measurements. The technique utilized a 384-well plate, and the measurements were made at the edge of a 10 × 10 cm field and compared to film measurements. During these penumbra measurements, while observing the positional differences in the higher gradient region at 4.1 and 4.55 cm from the center of the radiation field, the distance to agreement of PDSB to film were 0.38 cm and 0.26 cm while the distance to agreement of PDSB to film were 0.11 cm and 0.06 cm, respectively. Finally, the developed new separation technique reduced the time needed for the analysis of 25 samples from 200 min to 30 min.
先前开发了一种 DNA 剂量计(DNAd),该剂量计使用双链断裂(DSB)来测量剂量。该剂量计已在建立瞬态带电粒子平衡(TCPE)的情况下进行了剂量测量测试。双链断裂概率(PDSB)是剂量计中双链断裂的 DNA(dsDNA)与初始未断裂的 dsDNA 的比率,用于定量 DSB 并与剂量相关。这项工作的目标是开发一种新的技术来处理和分析 DNAd 并定量 DNA-DSB。该技术包括同时处理多个 DNAd,并建立一种新的双链断裂概率(PDSB)形式,然后通过测量束半影来在非 TCPE 条件下测试 DNAd。该技术利用了 384 孔板,并且在 10×10cm 场的边缘进行了测量,并与胶片测量进行了比较。在这些半影测量过程中,在观察辐射场中心 4.1 和 4.55cm 处较高梯度区域的位置差异时,PDSB 与胶片的符合距离分别为 0.38cm 和 0.26cm,而 PDSB 与胶片的符合距离分别为 0.11cm 和 0.06cm。最后,开发的新分离技术将分析 25 个样本所需的时间从 200 分钟缩短到 30 分钟。