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We have developed a low threshold detector consisting of Bragg curve counter (BCC), two siliconsurface barrier detectors (SSDs) and BGO scintillator to obtain experimental double-differential cross section (DDX) data for low energy proton production. Since the BCC offers advantage of self particle identification capability and a few μm-thick entrance window, protons produced by nuclear reactions down to 1 MeV have been identified. The capability of the detector is demonstrated in measurements using 70-MeV protons. Measured spectra are compared with calculation results of intra-nuclear cascade (INC) plus evaporation models and nuclear data library.

Double differential cross sections (DDXs) of light mass fragment (LMFs - Li,Be,B,C,N and O) productions were measured for tens of MeV proton, deuteron helium and carbon induced reactions on Be, C, Al, Ti and Cu targets. The incident energies for the measurements were chosen to allow us to compare DDXs with same incident energy but different projectiles on various targets. Systematic data were obtained to see the differences between projectile energies, particles, targets and emitted particles. From the comparison, reaction processes of not only evaporation from complete fusion nucleus, but also scattering, pickup, stripping and projectile fragmentation were observed.

A fundamental understanding of the design of polymer ligands of proximal enzymes is essential for the precise targeting of cancer cells, but it is still in its infancy. In this study, we systematically investigated the contribution of the chain length, ligand density, and ligand ratio of proximal enzyme-targeted polymers to the efficacy, synergy, and selectivity for the inhibition of cancer cell proliferation. The results revealed that employing a moderate chain length as a scaffold allowed for an intrinsically high efficacy and synergy of proximal enzyme-targeted polymers, in contrast to single enzyme-targeted polymers that prefer longer chain length for efficacy. The synergy obtained in proximal enzyme targeting was not provided by the combination of the corresponding small molecules. Moreover, the maturation of the synergistic efficacy of the proximal enzyme-targeted polymers also improved selectivity. This study proposes a rational design for polymer inhibitors and/or ligands for cancer cells with a high efficacy and selectivity.

Diagnostic reference level (DRL) for mammography for 2015 and 2020 has been published by J-RIME. More new dose studies are needed to revise the next DRL. In preparation for the next revision of the DRL for mammography, this study investigated data from the Japan Central Organization on Quality Assurance of Breast Cancer Screening on the mean average glandular dose (AGD) for institutional image accreditation in 2019-2023 and the relationship between the average at eligible institutions to date and the type of breast X-ray system. The 95th percentile values of the AGD distributions for the Computed Radiography (CR) and Flat Panel Detector (FPD) systems were 2.5 mGy and 2.0 mGy, respectively. Moreover, it is assumed that AGD is decreasing due to the spread of FPD systems, and it is expected that the further spread of FPD systems and systems with W/Rh target/filter will reduce AGD in future., (© 2024. The Author(s), under exclusive licence to Japanese Society of Radiological Technology and Japan Society of Medical Physics.)

Paroxysmal cold hemoglobinuria (PCH) is a rare disease in adults, and its concurrent presentation with warm-type autoimmune hemolytic anemia (AIHA) has not yet been reported. We encountered a 19-year-old woman with AIHA and a positive Donath-Landsteiner test result identified by a hemolytic attack during blood transfusion. She also showed positive results for the direct Coombs and Donath-Landsteiner antibody tests. After treatment with prednisolone followed by rituximab, the AIHA improved, and the Donath-Landsteiner antibody test result turned negative. Clinicians should be aware that patients may present with concurrent warm-type AIHA and PCH and consider rituximab for its treatment.

We conducted a molecular epidemiological study of Staphylococcus aureus using whole-genome sequence data and clinical data of isolates from nasal swabs of patients admitted to the intensive care unit (ICU) of Hiroshima University hospital. The relationship between isolate genotypes and virulence factors, particularly for isolates that caused infectious diseases during ICU admission was compared with those that did not. The nasal carriage rates of methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) in patients admitted to the ICU were 7.0% and 20.1%, respectively. The carriage rate of community-acquired (CA)-MRSA was 2.3%, accounting for 32.8% of all MRSA isolates. Whole-genome sequencing analysis of the MRSA isolates indicated that most, including CA-MRSA and healthcare-associated (HA)-MRSA, belonged to clonal complex (CC) 8 [sequence type (ST) 8] and SCC mec type IV. Furthermore, results for three disease foci (pneumonia, skin and soft tissue infection, and deep abscess) and the assessment of virulence factor genes associated with disease conditions [bacteremia, acute respiratory distress syndrome (ARDS), disseminated intravascular coagulopathy (DIC), and septic shock] suggested that nasal colonization of S. aureus clones could represent a risk for patients within the ICU. Particularly, MRSA/J and MSSA/J may be more likely to cause deep abscess infection; ST764 may cause ventilation-associated pneumonia, hospital-acquired pneumonia and subsequent bacteremia, and ARDS, and tst-1 -positive isolates may cause DIC onset.IMPORTANCENasal colonization of MRSA in patients admitted to the intensive care unit (ICU) may predict the development of MRSA infections. However, no bacteriological data are available to perform risk assessments for Staphylococcus aureus infection onset. In this single-center 2-year genomic surveillance study, we analyzed all S. aureus isolates from nasal swabs of patients admitted to the ICU and those from the blood or lesions of in-patients who developed infectious diseases in the ICU. Furthermore, we identified the virulent clones responsible for causing infectious diseases in the ICU. Herein, we report several virulent clones present in the nares that are predictive of invasive infections. This information may facilitate the design of preemptive strategies to identify and eradicate virulent MRSA strains, reducing nosocomial infections within the ICU., Competing Interests: The authors declare no conflict of interest.

Dose-averaged linear energy transfer (LET d ) is conventionally evaluated from the relative biological effectiveness (RBE)-LET d fitted function used in the treatment planning system. In this study, we calculated the physical doses and their linear energy transfer (LET) distributions for patterns of typical CIRT beams using Monte Carlo (MC) simulation. The LET d was then deduced from the MC simulation and compared with that obtained from the conventional method. The two types of LET d agreed well with each other, except around the distal end of the spread-out Bragg peak. Furthermore, an MC simulation was conducted with the material composition of water and realistic materials. The profiles of physical dose and LET d were in good agreement for both techniques. These results indicate that the previous studies to analyze the minimum LET d in CIRT cases are valid for practical situations, and the material composition conversion to water little affects the dose distribution in the irradiation field., (© 2024. The Author(s), under exclusive licence to Japanese Society of Radiological Technology and Japan Society of Medical Physics.)