PIXE analysis of magnetic spherules in Paleozoic-Mesozoic bedded chert

Particle Induced X-ray Emission (PIXE) was applied to the elemental characterization of magnetic microspherules collected from the Paleozoic and Mesozoic bedded chert in Southwest Japan. Comparison of the titanium and chromium contents of the spherules with the magnetic components of meteorites and volcanic ash showed that this technique offers promising potential as a new method for distinguishing between spherules of terrestrial and extraterrestrial origin

Tissue-specific expression of histone H3 variants diversified after species separation

Additional file 3: Predicted CDS of human histone H3/H4 variants, contains Table S2, which lists the CDS locus information of the predicted human histone H3 and H4 variants in an Excel file

High-sensitivity quantitative analysis reveals the non-linear relationship between the dose and deposition of diphenylarsinic acid in the rat central nervous system following its subchronic exposure

In the year 2003, the residents of Kamisu, Japan, were exposed to pentavalent organic arsenic diphenylarsinic acid (DPAA[V]) via their normal drinking water. Following the exposure, they developed cerebellar and brainstem symptoms. Although the relatively high dose of DPAA(V) is assumed to have caused their symptoms, the relationship between the exposed dose of DPAA(V) and the level of their deposition in the central nervous system (CNS) remains unclear. Using liquid chromatography–tandem mass spectrometry, we examined the deposition of DPAA(V) and its pentavalent metabolites in the CNS tissues of Crl:CD(SD) rats following the administration of DPAA(V) for 28 days. We found that the concentrations of DPAA(V) in the CNS were very high, given a dose of 5.0 mg/kg/day. However, very low concentrations of DPAA(V) were detected at a dose of 0.3 or 1.2 mg/kg/day, suggesting the absence of a linear dose-response relationship between the dose and deposition of DPAA(V). We also found that this non-linear relationship was commonly observed in various non-CNS tissues, including the excretory system. Our study showed for the first time the exact relationship between the dose and tissue deposition of the organic arsenic following its subchronic administration

A Comparison of Physical vs. Nonphysical Wedge Modalities in Radiotherapy

This chapter discusses the clinical application and implementation of wedge techniques in radiation therapy. Coverage of the target region with a curative dose is critical for treating several cancer types; to that end, wedge filters are commonly used to improve dose uniformity to the target volume. Initially, wedges designed for this purpose were physical and were made of high-density materials such as lead or steel. Subsequently, nonphysical wedges were introduced; these improved the dose uniformity using computer systems in lieu of physical materials. As wedge systems evolve, however, they each continue to have their advantages and disadvantages. When using physical wedges, it is difficult to control the generation of secondary radiation resulting from the collision of the radiation beam with the wedge body; conversely, nonphysical wedges do not create any secondary radiation because there is no physical interference with the beam. On the other hand, nonphysical wedges are less suitable for treating moving tumors, such as those in the lung, and physical wedges have better dose coverage to the target volume than nonphysical wedges. This chapter aims to guide decision-making regarding the choice of wedge types in various clinical situations

Gliosarcoma arising from a fibrillary astrocytoma

We report a 67-year-old woman who was diagnosed with a gliosarcoma at a second operation after diagnosis of a fibrillary astrocytoma 5 months previously. Initially, she underwent a CT-guided stereotactic biopsy. Histological examination showed fibrillary astrocytoma (World Health Organization [WHO] grade II). Loss of heterozygosity (LOH) on 1 p, 10q, and 19q was not detected. She received chemotherapy, but no radiotherapy. Five months after the biopsy, MRI revealed rapid tumor growth. Tissue obtained from partial removal of the tumor revealed gliosarcoma (WHO grade IV), and LOH on 10q and 19q was detected. The history, histopathology, and genetic alterations of this patient are discussed.ArticleJOURNAL OF CLINICAL NEUROSCIENCE. 18(9):1251-1254 (2011)journal articl

Long-term accumulation of diphenylarsinic acid in the central nervous system of cynomolgus monkeys

Diphenylarsinic acid (DPAA) is an organic arsenic compound used for the synthesis of chemical weapons. We previously found that the residents of Kamisu city in Ibaraki Prefecture, Japan, were exposed to DPAA through contaminated well water in 2003. Although mounting evidence strongly suggests that their neurological symptoms were caused by DPAA, the dynamics of DPAA distribution and metabolism after ingestion by humans remain to be elucidated. To accurately predict the distribution of DPAA in the human body, we administrated DPAA (1.0 mg/kg/day) to cynomolgus monkeys (n = 28) for 28 days. The whole tissues from these monkeys were collected at 5, 29, 170, and 339 days after the last administration. The concentration of DPAA in these tissues was measured by liquid chromatography–mass spectrometry. We found that DPAA accumulated in the central nervous system tissues for a longer period than in other tissues. This finding would extend our knowledge on the distribution dynamics and metabolism of DPAA in primates, including humans. Furthermore, it may be useful for developing a treatment strategy for patients who are exposed to DPAA

A clinically applicable and scalable method to regenerate T-cells from iPSCs for off-the-shelf T-cell immunotherapy

動物由来の成分を含まないより安全な製法でiPS細胞から大量の再生T細胞を培養する方法の開発 --T細胞を使ったがん免疫療法での利用も--. 京都大学プレスリリース. 2021-01-18.Clinical successes demonstrated by chimeric antigen receptor T-cell immunotherapy have facilitated further development of T-cell immunotherapy against wide variety of diseases. One approach is the development of “off-the-shelf” T-cell sources. Technologies to generate T-cells from pluripotent stem cells (PSCs) may offer platforms to produce “off-the-shelf” and synthetic allogeneic T-cells. However, low differentiation efficiency and poor scalability of current methods may compromise their utilities. Here we show improved differentiation efficiency of T-cells from induced PSCs (iPSCs) derived from an antigen-specific cytotoxic T-cell clone, or from T-cell receptor (TCR)-transduced iPSCs, as starting materials. We additionally describe feeder-free differentiation culture systems that span from iPSC maintenance to T-cell proliferation phases, enabling large-scale regenerated T-cell production. Moreover, simultaneous addition of SDF1α and a p38 inhibitor during T-cell differentiation enhances T-cell commitment. The regenerated T-cells show TCR-dependent functions in vitro and are capable of in vivo anti-tumor activity. This system provides a platform to generate a large number of regenerated T-cells for clinical application and investigate human T-cell differentiation and biology