RESUMO
Introduction: While carbon ion radiotherapy is highly effective in cancer treatment, it has a high risk of causing soft error, which leads to malfunctions in cardiac implantable electrical devices (CIEDs). To predict the risk of malfunction prior to treatment, it is necessary to measure the reaction cross-sections and contributions to the soft error of secondary particles generated during treatments. Methods: A field-programmable gate array was used instead of CIEDs to measure soft errors by varying the energy spectrum of secondary particles. Results and discussion: The reaction cross-sections measured for each secondary particle were 3.0 × 10-9, 2.0 × 10-9, 1.3 × 10-8, and 1.5 × 10-8 [cm2/Mb] for thermal neutrons, intermediate-energy neutrons, high-energy neutrons above 10 MeV, and protons, respectively. The contribution of high-energy neutrons was the largest among them. Our study indicates that to reduce the risk of soft errors, secure distance and appropriate irradiation directions are necessary.
RESUMO
Since phosphatidylserine (PS) is known to translocate to the external face of the plasma membrane when the cell membrane becomes disordered, we decided to focus our attention on PS as a target molecule for gene delivery. In this paper, the novel peptide Td3701 was designed, synthesized, and characterized for its physico-chemico-biological properties. Td3701 simultaneously exhibited both characters as a DNA carrier and a sensor probe for active targeting, which seemed to be triggered by structural changes in the presence of PS. This is a very unique character among nonviral vectors, and it is believed that Td3701 could be used for selective gene delivery.