English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

There are few reports on the biological homogeneity within the spread-out Bragg peak (SOBP) of proton beams. Therefore, to evaluate the relative biological effectiveness (RBE) and the oxygen enhancement ratio (OER), human salivary gland tumor (HSG) cells were irradiated at the plateau position (position A) and three different positions within a 6-cm-wide SOBP (position B, 26 mm proximal to the middle; position C, middle; position D, 26 mm distal to the middle) using 155-MeV/n proton beams under both normoxic and hypoxic conditions at the Proton Medical Research Center, University of Tsukuba, Japan. The RBE to the plateau region (RBE(plateau)) and the OER value were calculated from the doses corresponding to 10% survival data. Under the normoxic condition, the RBE(plateau) was 1.00, 0.99 and 1.09 for positions B, C and D, respectively. Under the hypoxic condition, the RBE(plateau) was 1.10, 1.06 and 1.12 for positions B, C and D, respectively. The OER was 2.84, 2.60, 2.63 and 2.76 for positions A, B, C and D, respectively. There were no significant differences in either the RBE(plateau) or the OER between these three positions within the SOBP. In conclusion, biological homogeneity need not necessarily be taken into account for treatment planning for proton beam therapy at the University of Tsukuba.

journal of radiation research

RBE and OER within the spread-out Bragg peak for proton beam therapy: in vitro study at the Proton Medical Research Center at the University of Tsukuba