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Auger electrons can induce nanoscale physiochemical damage to DNA. The present study reports a sequential and systematic evaluation of the relationship between DNA damage such as double-strand breaks (DSBs) and the cell cycle for the Auger electron-emitting agent radiolabeled cisplatin with DNA binding ability. For dynamic imaging analysis, we used U2OS-derived cancer cells expressing two fluorescent fusion proteins: tumor-suppressor p53 binding protein 1 with a green fluorescent protein (53BP1-EGFP) and proliferating cell nuclear antigen with a red fluorescent protein (PCNA-DsRed). Time-lapse images of the cells were quantitatively analyzed using the ImageJ software with the deepImageJ plugin and the Google Colaboratory platform. From the middle-to-late G1 phase, around the G1-to-S phase transition, we found increased 53BP1 foci in cells treated with the radio-cisplatin. The radio-cisplatin caused significantly more DSBs than the nonradioactive cisplatin and saline in the G1 phase but not in the other phases. These results indicate that Auger electron-induced DNA damage, including DSBs, depends on the cell cycle. The G1 phase, which is associated with low DNA repair capacity and high radiosensitivity, is a promising target; thus, combining radiolabeled cisplatin with agents that arrest cells in the G1 phase could improve the DNA-damaging effect of Auger electrons and their therapeutic efficacy.

[Background] Use of the Glatzel mirror for measuring expiratory nasal flow in preschool children has the disadvantage of vagueness, and the mirror may induce fear and inhibition of interest in those children. In response to these limitations, we developed a new device with dual cameras for measuring expiratory nasal flow in 2 to 6 year old children. The aim of this study is to compare the Glatzel mirror and the new device, in terms of accurate assessment of expiratory nasal flow, children’s feelings, and correlation to each child’s profile. [Methods] This study evaluated 20 cleft lip and palate patients and 21 healthy children aged between 2 and 6 (under 7) years. After consent was granted, a 4-week screening period was undertaken followed by inspection at weeks 8, 16, 24, and 32. Each inspection was conducted while the children were asked to pronounce various sounds and comprised three stages: i) use of the Glatzel mirror, ii) subjective visual assessment using the new device, and iii) image recording by dual cameras of the new device. Questionnaires for the new device were administered at the initial and final inspections. To contrast the results between the Glatzel mirror and the new device, the numbers that indicated values of subjective visual assessment and camera assessment greater than the assessment values of the Glatzel mirror were compared. For measuring the children’s responses to the new device compared with those to the Glatzel mirror, the answers to the questionnaires were compared. For the comparison of the children’s profiles (age and sex) and feelings, the numbers of subjects who could use the new device were measured. [Results] The camera assessment of the new device indicated significantly greater values than that of the Glatzel mirror (P < 0.05). The feelings of the subjects to the new device mostly improved as the study progressed. Subjects aged 3 years and older were generally able to use the new device from the initial inspection. For both sexes, as the inspection progressed, the number occasions of successful use increased. [Conclusion] This study demonstrated the superiority of the new device with dual cameras to the Glatzel mirror in terms of functionality and attitude of children.

In-plane mesopatterns derived from block-copolymer (BCP) micro-phase segregation in thin films have attracted much interest in practical applications as well as fundamental research programs. However, phase segregation along the film-normal direction has been less studied. Here, we describe a strategy to concurrently, yet independently, control in-plane micro-phase and out-of-plane macro-phase segregation in multiblended films composed of liquid-crystalline BCPs (LCBCPs), affording spontaneously layered three-dimensional (3D) mesostructures. This strategy relies on sequential liquid crystallization during the cooling process in thermal annealing as follows. The constituent LCBCP with the highest isotropic-transition temperature (T(iso)) first liquid-crystallizes and segregates from the other LCBCP mixture remaining in isotropic states to form a noncontaminated layer at the top surface. This preformed LCBCP layer preserves its inherent in-plane pattern and acts as a template guiding the subsequent micro-phase segregations of the other low-T(iso) LCBCPs underneath. This self-template–assisted micro-phase segregation (STAMPS) readily provides 3D mesostructures, the potential toward rational material design of which is also demonstrated in water-separation applications.