{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T06:33:41Z","timestamp":1793428421577,"version":"4.5.0"},"reference-count":41,"publisher":"Radiation Research Society","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Radiation Research"],"published-print":{"date-parts":[[2023,4,4]]},"abstract":"<jats:p>Low-energy X-ray sources that operate in the kilovoltage energy range have been shown to induce more cellular damage when compared to their megavoltage counterparts. However, low-energy X-ray sources are more susceptible to the effects of filtration on the beam spectrum. This work sought to characterize the biological effects of the Xoft Axxent\u00ae source, a low-energy therapeutic X-ray source, both with and without the titanium vaginal applicator in place. It was hypothesized that there would be an increase in relative biological effectiveness (RBE) of the Axxent\u00ae source compared to 60Co and that the source in the titanium vaginal applicator (SIA) would have decreased biological effects compared to the bare source (BS). This hypothesis was drawn from linear energy transfer (LET) simulations performed using the TOPAS Monte Carlo user code as well a reduction in dose rate of the SIA compared to the BS. A HeLa cell line was maintained and used to evaluate these effects. Clonogenic survival assays were performed to evaluate differences in the RBE between the BS and SIA using 60Co as the reference beam quality. Neutral comet assay was used to assess induction of DNA strand damage by each beam to estimate differences in RBE. Quantification of mitotic errors was used to evaluate differences in chromosomal instability (CIN) induced by the three beam qualities. The BS was responsible for the greatest quantity of cell death due to a greater number of DNA double strand breaks (DSB) and CIN observed in the cells. The differences observed in the BS and SIA surviving fractions and RBE values were consistent with the 13% difference in LET as well as the factor of 3.5 reduction in dose rate of the SIA. Results from the comet and CIN assays were consistent with these results as well. The use of the titanium applicator results in a reduction in the biological effects observed with these sources, but still provides an advantage over megavoltage beam qualities. \u00a9 2023 by Radiation Research Society<\/jats:p>","DOI":"10.1667\/rade-22-00112.1","type":"journal-article","created":{"date-parts":[[2023,4,4]],"date-time":"2023-04-04T13:28:52Z","timestamp":1680614932000},"page":"429-438","source":"Crossref","is-referenced-by-count":3,"title":["Biological Characterization of the Effects of Filtration on the Xoft Axxent\u00ae Electronic Brachytherapy Source for Cervical Cancer Applications"],"prefix":"10.1667","volume":"199","author":[{"given":"Autumn E.","family":"Walter","sequence":"first","affiliation":[{"name":"Department of Medical Physics"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pippa F.","family":"Cosper","sequence":"additional","affiliation":[{"name":"Department of Human Oncology, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kwangok P.","family":"Nickel","sequence":"additional","affiliation":[{"name":"Department of Human Oncology, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shrey","family":"Ramesh","sequence":"additional","affiliation":[{"name":"Department of Human Oncology, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahtesham U.","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Medical Physics"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Larry A.","family":"DeWerd","sequence":"additional","affiliation":[{"name":"Department of Medical Physics"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Randall J.","family":"Kimple","sequence":"additional","affiliation":[{"name":"Department of Medical Physics"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1243","reference":[{"key":"35","doi-asserted-by":"crossref","unstructured":"J Perl, J Shin, J Sch\u00fcmann, et al.  \"Med Phys.\"  39, \"TOPAS: an innovative proton Monte Carlo platform for research and clinical applications.\" 6818 (2012)","DOI":"10.1118\/1.4758060"},{"key":"27","doi-asserted-by":"crossref","unstructured":"Z Mao, M Bozzella, A Seluanov, et al.  \"DNA Repair (Amst).\"  7, \"Comparison of nonhomologous end joining and homologous recombination in human cells.\" 1765 (2008)","DOI":"10.1016\/j.dnarep.2008.06.018"},{"key":"41","doi-asserted-by":"crossref","unstructured":"S Eschrich, H Zhang, H Zhao, et al.  \"Int J Radiat Oncol Biol Phys.\"  75, \"Systems biology modeling of the radiation sensitivity network: a biomarker discovery platform.\" 497 (2009)","DOI":"10.1016\/j.ijrobp.2009.05.056"},{"key":"1","doi-asserted-by":"crossref","unstructured":"R Nath, LL Anderson, G Luxton, et al.  \"Med Phys.\"  22, \"Dosimetry of interstitial brachytherapy sources: Recommendations of the AAPM Radiation Therapy Committee Task Group No. 43.\" (1995)","DOI":"10.1118\/1.597458"},{"key":"2","doi-asserted-by":"crossref","unstructured":"DJ. Eaton,  \"Br J Radiol.\"  88, \"Electronic brachytherapy-current status and future directions.\" (2015)","DOI":"10.1259\/bjr.20150002"},{"key":"3","doi-asserted-by":"crossref","unstructured":"MJ Rivard, SD Davis, LA DeWerd, et al.  \"Med Phys.\"  33, \"Calculated and measured brachytherapy dosimetry parameters in water for the Xoft Axxent X-Ray Source: An electronic brachytherapy source.\" (2006)","DOI":"10.1118\/1.2357021"},{"key":"4","unstructured":"\"Operator Manual Axxent Controller Model 110 Rev. 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Research"],"original-title":[],"link":[{"URL":"https:\/\/meridian.allenpress.com\/radiation-research\/article-pdf\/doi\/10.1667\/RADE-22-00112.1\/3205094\/10.1667_rade-22-00112.1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/meridian.allenpress.com\/radiation-research\/article-pdf\/doi\/10.1667\/RADE-22-00112.1\/3205094\/10.1667_rade-22-00112.1.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T06:04:43Z","timestamp":1793426683000},"score":1,"resource":{"primary":{"URL":"https:\/\/bioone.org\/journals\/radiation-research\/volume-199\/issue-5\/RADE-22-00112.1\/Biological-Characterization-of-the-Effects-of-Filtration-on-the-Xoft\/10.1667\/RADE-22-00112.1.full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,4,4]]},"references-count":41,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2023,5,1]]}},"URL":"https:\/\/doi.org\/10.1667\/rade-22-00112.1","relation":{},"ISSN":["0033-7587","1938-5404"],"issn-type":[{"value":"0033-7587","type":"print"},{"value":"1938-5404","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,4,4]]}}}