Visualization of dose distribution and basic study of dose estimation using plastic scintillator and digital camera.

Radiation can be visualized using a scintillator and a digital camera. If the amount of light emitted by the scintillator increases with dose, the dose estimation can be obtained from the amount of light emitted. In this study, the basic performance of the scintillator and digital camera system was evaluated by measuring computed tomography dose index (CTDI). A circular plastic scintillator plate was sandwiched between polymethyl methacrylate (PMMA) phantoms, and x-rays were irradiated to them while rotating the x-ray tube to confirm changes in light emission. In addition, CTDI was estimated from the amount of light emitted by the scintillator during the helical scan and compared with the value measured from dosimeter. The scintillator emitted light while changing its distribution according to the movement of the x-ray tube. The measured CTDIvolwas 33.20 mGy, the CTDIvolestimated from the scintillation light was approximately 46 mGy, which was 40% larger. In particular, when the scintillator was directly irradiated, the dose was overestimated compared with the value measured from the dosimeter. This overestimation can be because of the reproducibility of the position and the difference between the sensitivity of the scintillator to detect light emission and the sensitivity of the dosimeter, and the non-uniformity of position sensitivity due to the wide-angle lens.

Post-Marketing Surveillance Study of the Safety and Efficacy of Nalfurafine (Capsules 2.5 µg, Oral Dispersing Tablets 2.5 µg) in 1186 Patients with Chronic Liver Disease and Intractable Pruritus.

Background: Nalfurafine (Remitch®, Toray Industries, Inc.) is a selective κ-receptor agonist approved in Japan for the improvement of pruritus in patients with chronic liver diseases (only when existing treatments bring insufficient efficacy) in May 2015. Methods: A post-marketing Specific Drug Use Survey was conducted in Japan (March 1, 2016 to June 30, 2020) of the safety and efficacy of nalfurafine for the improvement of pruritus in patients with chronic liver disease. Results: Among 1186 cases analyzed for safety, the incidence of adverse drug reactions was 9.4% (112/1186 cases), lower than 61.4% reported in pre-marketing surveillance (297/484 cases). No specific safety issues were found and no cases of concern for drug dependence identified. Efficacy (itch improvement) was demonstrated in 73.16% (815/1114 cases; 12-week analysis set) and in 85.67% (520/607; general assessment of itch improvement at 1-year analysis set). A significant difference was found in 4 items of itch improvement at 12 weeks and 8 items of itch improvement at 1 year. No noteworthy issues were identified. Mean Visual Analog Scale (VAS) values after 12 weeks and 1 year after the first dose were significantly lower than the baseline (p < 0.0001 for both treatment durations). Mean severity scores (Kawashima's classification scheme) were significantly lower than the pretreatment score at 12 weeks and 1 year after the first dose (both p < 0.0001). No concerns were identified in the efficacy and safety of nalfurafine in patients with specific background, ie, the elderly (aged ≥ 65 years), those with renal impairment, and those on long-term treatment (≥ 365 days) compared with patients without corresponding background. Conclusion: No new safety issues of concern or cases of insufficient efficacy were identified in this Specific Drug Use Survey of the safety and efficacy of nalfurafine for the improvement of pruritus in patients with chronic liver diseases.

Basic study of mobile gamma ray imaging using a digital camera and scintillator.

Gamma cameras are used in nuclear medicine examinations involving radioisotopes; however, they do not provide real-time feedback. We propose a real-time imaging method based on a commercially available digital camera and a scintillator array to provide simple and accurate measurements of radioisotope accumulation and contamination. We evaluate the sensitivity and resolution of the proposed device using x-rays as a proxy for gamma-rays. The performance of the device is demonstrated using PENTAX KP and ORCA-spark C11440-36U digital cameras. A caesium iodide scintillator array is irradiated with x-rays, with the state of light emission confirmed using live view images. The pixel value is evaluated as a function of dose rate. Furthermore, we investigate the state of light emission in response to amplifying the light signal using an image intensifier. For the PENTAX KP, luminescence is observable for a dose rate of approximately 10 mSv h-1, which changes to 2.1 mSv h-1when an image intensifier is used. Notably, the ORCA-spark detected emission at a low dose rate of 0.06 mSv h-1. However, using an image intensifier resulted in noisier images. Therefore, although the ORCA-spark can observe luminescence at a suitable predicted dose rate for application in nuclear medicine examinations, a collimator is required to control the spread of gamma rays. However, as this causes the sensitivity to decrease, increasing the amount of light emitted by the scintillator and improving the sensitivity of the camera is vital.

Sulfur-inserted polymer-anchored edge exfoliated graphite for durable positive electrodes for lithium-sulfur batteries.

Lithium-sulfur batteries hold promising potential for next-generation high-energy-density energy storage. One of their major technical problems is the sulfur active material loss and significant volume change during the charge-discharge process, resulting in rapid capacity fading. Here, we propose sulfur-inserted polymer-anchored edge exfoliated graphite as a positive electrode to accommodate the conflicting requirement of physically restraining sulfur dissolution while maintaining structural flexibility to cope with the volume expansion. The introduction of sulfur between the flexible polymer-anchored graphene layers is achieved by a simple chemical reaction at ambient temperature. The obtained sulfur-carbon composite demonstrates superior sulfur efficiency and cyclability compared to mesoporous carbon-based counterparts. The strong interfacial attraction between sulfur and highly-conductive graphene sheets at the confined interlayer space enables rapid charge transfer and effectively inhibits the polysulfide dissolution, resulting in improved redox reaction reversibility and sulfur efficiency. More importantly, the structural flexibility of layered structure, derived from polymer-anchor, guarantees the stable cycling by accommodating the significant volume expansion of sulfur active materials. Our work provides a simple, proof-of-concept strategy for improving the overall performance of carbon-based positive electrode for Li-S batteries.

Post-marketing surveillance study of the safety and efficacy of nalfurafine hydrochloride (Remitch® capsules 2.5 µg) in 3,762 hemodialysis patients with intractable pruritus.

BACKGROUND: Intractable pruritus in hemodialysis patients can significantly decrease their quality of life and is also associated with poor vital prognosis. Although combined multiple causes of intractable pruritus in these patients have been identified, no existing treatments are proven to be sufficiently effective. We conducted a post-marketing surveillance to follow-up and assess the safety and efficacy of nalfurafine, a selective κ-opioid receptor agonist, for the treatment of intractable pruritus in patients undergoing hemodialysis. PATIENTS AND METHODS: Hemodialysis patients with intractable pruritus from institutions in Japan who received oral nalfurafine hydrochloride between January 2010 and December 2013 were enrolled in the surveillance. Surveillance was completed in July 2015. Safety data during 1 year after nalfurafine treatment onset, and efficacy data of nalfurafine evaluating the first 12-week treatment period and the following period until 1 year after the initial dose of nalfurafine (using global assessment of the itch improvement by the physician, Visual Analog Scale, and the Shiratori's severity scores) were collected and analyzed. RESULTS: In total, 3,762 patients were analyzed for safety. Adverse drug reactions were experienced by 402/3,762 (10.69%) patients. The most frequent adverse drug reactions were insomnia (127/3,762 [3.38%] patients), constipation (34 [0.90%]), somnolence (32 [0.85%]), dizziness (23 [0.61%]), nausea (13 [0.35%]), and malaise (9 [0.24%]). No patients developed dependence on nalfurafine. Nalfurafine was effective in 82.50% (2,880/3,491) of patients during the first 12 weeks and in 84.95% (2,167/2,551) on treatment during the subsequent period until 1 year after nalfurafine treatment initiation. Statistically significant decreases were reported in the Visual Analog Scale and the Shiratori's severity scores (p<0.001). CONCLUSION: Oral nalfurafine hydrochloride (from 2.5 µg/day to a maximum of 5.0 µg/day) continues to be safe and effective for the treatment of intractable pruritus in hemodialysis patients in real-world clinical settings.

BTB-ZF Protein Znf131 Regulates Cell Growth of Developing and Mature T Cells.

Many members of the BTB-ZF family have been shown to play important roles in lymphocyte development and function. The role of zinc finger Znf131 (also known as Zbtb35) in T cell lineage was elucidated through the production of mice with floxed allele to disrupt at different stages of development. In this article, we present that Znf131 is critical for T cell development during double-negative to double-positive stage, with which significant cell expansion triggered by the pre-TCR signal is coupled. In mature T cells, Znf131 is required for the activation of effector genes, as well as robust proliferation induced upon TCR signal. One of the cyclin-dependent kinase inhibitors, p21(Cip1) encoded by cdkn1a gene, is one of the targets of Znf131. The regulation of T cell proliferation by Znf131 is in part attributed to its suppression on the expression of p21(Cip1).

Investigation of the structure of cellulose in LiCl/DMAc solution and its gelation behavior by small-angle X-ray scattering measurements.

Cellulose gels were prepared from cellulose in lithium chloride/N,N-dimethylacetamide (LiCl/DMAc) solution. When the cellulose concentration in the solution is above the one at which cellulose molecules overlap, cellulose gels were formed. While the gel prepared by the addition of water was turbid, the one prepared by the ion exchange was colorless, transparent, and optically anisotropic. In order to explain this gelation behavior of cellulose, small-angle X-ray scattering (SAXS) measurements of the cellulose solutions and the gels were performed. The SAXS profiles of the cellulose solutions and the gels suggested that the large-scale fluctuation of the molecular chain density in the solution can be the origin of the molecular aggregates formed in the gel. Furthermore, the differences in the structure of the gels at the macroscopic and the molecular level were discussed in terms of the phase separation and the molecular association.