National Institutes for Quantum and Radiological Science and Technology
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Local therapy with hypoxia-targeting radiopharmaceutical [Cu]Cu-ATSM in high-grade glioma patient-derived xenograft models.
No full textWorld Health Organization (WHO)-defined central nervous system (CNS) grade 4 high-grade gliomas (HGGs) are aggressive brain tumors marked by hypoxia and diffuse infiltration, which leaves residual tumor cells after surgery and drives inevitable local recurrence. Here, we propose a novel local therapeutic approach with Cu-diacetyl-bis(N4-methylthiosemicarbazone) ([Cu]Cu-ATSM), a hypoxia-targeting radiopharmaceutical, using HGG-patient-derived xenograft (PDX) models.journal articl
Consideration of density measurement using toroidal interferometer and polarimeter on JA DEMO
No full textThe toroidal interferometer and polarimeter (TIP) have been investigated as density diagnostics for JA DEMO. A model for the interferometer and polarimeter phase shifts incorporating the finite electron temperature effect has been implemented into a plasma control simulation code to generate the synthetic phase shift signals. The laser wavelength is set to 10.6 μm identical to that used in ITER. The finite temperature effect is significant. The deviation between the estimated line-averaged densities obtained with and without accounting for finite temperature effects reaches approximately 7% for the interferometer and 10% for the polarimeter along lines of sight near the magnetic axis, and decreases to a few percent near the outer edge. Density feedback control has been performed, and a comparison is made between the line-averaged densities with and without correction for the temperature effect. When the temperature effect is neglected, the density is underestimated, leading to an increase in the actual density. Consequently, the fusion output increases, resulting in an error of up to 11% when using the central viewing chords. Correction of the density error caused by the finite electron temperature has been carried out using TIP alone by taking the difference between the interferometer and polarimeter signals. The results show that it can reduce the density error to below 1%.journal articl
Genomic and transcriptomic characterization of gamma ray– and heavy ion–induced precursor B-cell lymphomas in B6C3F1 mice: Radiation type–dependent interstitial chromosomal deletions at tumor-suppressor gene loci
No full textEpidemiological studies have revealed that ionizing radiation is a risk factor for acute lymphoblastic leukemia. Humans can be exposed to radiation via clinical radiotherapies or spaceflight, yet our knowledge of the potential carcinogenic effects of various types of radiation remains incomplete. To address this shortcoming, we analyzed the development of precursor B-cell lymphoma (pBL) in B6C3F1 mice after irradiation with gamma rays or heavy ions (carbon, silicon, argon, or iron ions) followed by array comparative genomic hybridization, whole-exome sequencing, and RNA sequencing analyses. Heavy-ion irradiation predominantly induced late-onset pBLs. In addition, chromosomal deletions in late-onset pBLs depended on radiation type: gamma-ray-induced pBLs had interstitial deletions of chromosome 8 (del8) affecting the tumor-suppressor gene Cyld, whereas silicon-ion-induced pBLs had interstitial deletions of chromosome 19 (del19) affecting the tumor-suppressor genes Cd274, Pten, and Fas; notably, carbon ions induced both types of pBL and no pBLs harbored these deletions in the argon- or iron-ion-irradiated mice. Late-onset pBLs were classified into two clusters with differential mutation patterns based on their gene-expression profiles, and pBLs with del8 and del19 were classified into different gene-expression clusters. Furthermore, the mutational and transcriptomic profiles of the late-onset del8 pBLs were reminiscent of human activated B-cell-like diffuse large B-cell lymphoma (DLBCL) whereas those of the del19 pBLs resembled germinal center B-cell-like DLBCL. These results establish the molecular signatures in radiation-induced pBLs that depend on radiation type, which will help improve both targeted molecular therapies for patients and risk assessment after exposure.journal articl
Effect of multiple electron-hole pair excitations on x-ray magnetic circularly polarized emission.
No full textIn x-ray magnetic circularly polarized emission (XMCPE), circularly polarized characteristic x-rays are emitted from a magnetized material.In this study, we develop a theoretical method of calculating XMCPE spectra, considering multiple electron-hole pair excitations within the self-consistent perturbation theory (SCPT), and thereby calculate the XMCPE spectra specifically for ferromagnetic Fe (bcc), Co (hcp), and Ni (fcc).In a comparison of the SCPT results with previous results calculated within the Born approximation, the XMCPE spectra for SCPT are clearly broader in the low-energy side of the peaks than that for the Born calculation.The results show that the multiple electron-hole pair excitations play a significant role in x-ray emission processes.journal articl
Robustness of LETd-optimized multi-ion therapy against range and setup uncertainties: evaluation and enhancement with carbon-, oxygen-, and neon-ion beams
No full textObjective. The LET trilemma—an inherent conflict between target dose homogeneity, range robustness, and high dose-averaged linear energy transfer (LETd)—poses a major challenge in treatment optimization. To ensure accurate beam delivery in multi-ion therapy, this study evaluated the effects of range and setup uncertainties on LETd-optimized treatment plans and explored strategies to overcome this trilemma, framed within the phase I LETd escalation trial for head and neck cancers. Approach. Six head and neck cancer patients representing diverse tumors were selected. Multi-ion therapy plans using carbon-, oxygen-, and neon-ion beams were optimized to achieve a target LETd of 90 keV μm−1 (the final LETd level of the phase I trial). These plans were recalculated to incorporate systematic range uncertainty (±2.5%) and random daily setup variations (mean, 0.45 mm; standard deviation, 0.23 mm) across the 16 fractions, and their combined effects on the dose and LETd distributions were evaluated. Additionally, to explore strategies to enhance plan robustness, five modified plans were evaluated for one patient identified as particularly susceptible to these uncertainties. Main Results. Range uncertainty was the dominant contributor to degraded plan quality, substantially outweighing setup uncertainty. A small, centrally located tumor was most susceptible, exhibiting dose inhomogeneity of approximately 11%, while LETd variations were approximately 3 keV μm−1. The most effective mitigation strategy involved replacing the original carbon–oxygen combination with oxygen ions for two beam ports, reducing dose inhomogeneity by more than 7% while maintaining normal tissue sparing adjacent to the target. Significance. Optimization toward achieving higher LETd makes treatment plans susceptible to range uncertainty, leading to dose degradation within small, deep-seated tumors. Employing heavier ions is an effective strategy to overcome this challenge, enabling robust target coverage by leveraging their inherently higher LETd while sparing normal tissues. These findings provide a key rationale for ion selection in the design of robust multi-ion therapy.journal articl
In vivo deep-brain microscopy at submicrometer resolution with a refractive index-matched prism interface
No full text56th NIPS International Symposium Focus on Biophotonics and Neuroscience 2026にて「In vivo deep-brain microscopy at submicrometer resolution with a refractive index-matched prism interface」のタイトルでポスター発表を行う。56th NIPS International Symposium “Focus on Biophotonics and Neuroscience 2026conference poste
H-mode operation scenarios in JT-60SA initial research phase predicted by integrated core-pedestal-SOL/divertor simulation
No full textAn integrated simulation encompassing core-pedestal-SOL/divertor regions was performed for the first time in the world to establish H-mode operation scenarios in the JT-60SA initial research phase. The simulation demonstrated that the baseline H-mode scenario will achieve its target performance parameters for normalized beta β_N≥1.8 and energy confinement factor H_98y2≥1, while maintaining divertor heat flux well below maximum allowable limit q_∥<10MW/m^2 through controlled extrinsic impurity gas injection. This accomplishment addresses both ITER/DEMO-relevant operational objectives and scientific research priorities. The predictions were enabled by implementing advanced models and codes that analyze the complete plasma volume, with specific focus on achieving compatible density predictions between the SOL/divertor and pedestal regions to optimize both plasma performance and divertor heat load reduction. This integrated simulation framework significantly enhances predictive capabilities for future tokamak operations, providing essential insights for advancing research at JT-60SA, ITER, and next-generation fusion reactors.conference pape
Dose Constraints in Carbon-Ion Radiation Therapy to Minimize the Risk of Pectoral Myositis.
No full textCarbon-ion radiation therapy (C-ion RT) is an emerging nonsurgical treatment for early stage breast cancer, offering biological advantages such as high linear energy transfer (LET) and precise dose distribution. However, the risk of radiation-induced toxicity, particularly pectoral myositis, remains unclear. This study evaluates the relationship between RBE-weighted dose, LET, and pectoral myositis in patients receiving C-ion RT.journal articl
High-Dose Direct Irradiation to a Cardiac Resynchronization Therapy Defibrillator Infiltrated by Metastatic Thyroid Papillary Carcinoma in the Sternum: A Case Report.
No full textThe increasing number of cancer patients with cardio-vascular disease has led to a potential need for radiation therapy (RT) in patients with cardiovascular implantable electronic devices (CIEDs).1 RT should be well managed in patients with CIEDs because irradiation of CIEDs causes device malfunction, memory loss, deactivation, and resetting. Previous studies reported that the incidence of device malfunction in patients with CIEDs who under-went RT was 3% to 7%,2-4 and such device malfunction can be life-threatening.5,6The chances of device failure are considered to increase with higher RT doses delivered to the device. Although the definitive dose threshold that causes device malfunc-tion remains unclear, many guidelines use the dose received by the device as a factor when classifying risk.7-10 Moreover, because direct exposure of a device to irradia-tion is generally not recommended, there have been only a few case reports of a therapeutic dose delivered to a CIED so far.11-17 We herein report a case of CIED directly exposed to high-dose RT used to treat sternal metastasis from thyroid papillary carcinoma, along with a review of the literature.journal articl
A New Class of Zwitterionic Polymers Featuring Carbon-Centered Anions
No full textIn the domain of polymer and materials chemistry, polymers that incorporate both anionic and cationic groups within their structures—designated as polybetaines—occupy a prominent position due to their wide range of applications across various fields. A persistent challenge in polybetaine design has been the limited availability of chemical units, particularly for anionic moieties. Conventional polybetaines generally feature carboxylate, sulfonate, phosphate, or sulfonimide as counteranions. In this study, we present a approach that utilizes a naked carbanion as counteranions in polybetaines and preliminarily unveiled their antifouling properties against human whole blood.journal articl