Publications by authors named "Osamu Tomita"

In extended solid-state materials, the manipulation of chemical bonds through redox reactions often leads to the emergence of interesting properties, such as unconventional superconductivity, which can be achieved by adjusting the Fermi level through, , intercalation and pressure. Here, we demonstrate that the internal 'biaxial strain' in tri-layered fluorite oxychloride photocatalysts can regulate bond formation and cleavage without redox processes. We achieve this by synthesizing the isovalent solid solution Bi Sb YOCl, which undergoes a structural phase transition from the ideal BiYOCl structure to the SbYOCl structure with (Bi,Sb)O rings.

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Dye-sensitized photocatalysts with molecular dyes and widegap semiconductors have attracted attention because of their design flexibility, for example, tunable light absorption for visible-light water splitting. Although organic dyes are promising candidates as metal-free photosensitizers in dye-sensitized photocatalysts, their efficiency in H2 production has far been unsatisfactory compared to that of metal-complex photosensitizers, such as Ru(II) tris-diimine-type complexes. Here, we demonstrate the substantial improvement of carbazole-thiophene-based dyes used for dye-sensitized photocatalysts through systematic molecular design of the number of thiophene rings, substituents in the thiophene moiety, and the anchoring group.

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Background: Atypical teratoid/rhabdoid tumors (ATRT) are aggressive pediatric central nervous system malignancies that predominantly affect the brain and have poor survival outcomes. However, spinal ATRT is an uncommon subset of ATRT, and its clinical course and management are poorly understood.

Case: We describe a case of spinal ATRT in a previously healthy 5-year-old girl who initially presented with rapid-onset gait disturbance.

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Background: Cardiac dysfunction due to cardiotoxicity from anthracycline chemotherapy is a leading cause of morbidity and mortality in childhood cancer survivors (CCS), and the cumulative incidence of cardiac events has continued to increase. This study identifies an adequate indicator of cardiac dysfunction during long-term follow-up.

Procedure: In total, 116 patients (median age: 15.

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The success and continued expansion of research on metal-oxo clusters owe largely to their structural richness and wide range of functions. However, while most of them known to date are negatively charged polyoxometalates, there is only a handful of cationic ones, much less functional ones. Here, we show an all-inorganic hydroxyiodide [HSbO][HSbIO][SbI]·25HO (), forming a face-centered cubic structure with cationic SbO clusters and two types of anionic clusters in its interstitial spaces.

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Separation of photoexcited charge carriers in semiconductors is important for efficient solar energy conversion and yet the control strategies and underlying mechanisms are not fully established. Although layered compounds have been widely studied as photocatalysts, spatial separation between oxidation and reduction reaction sites is a challenging issue due to the parallel flow of photoexcited carriers along the layers. Here we demonstrate orthogonal carrier flow in layered BiNbOCl by depositing a Rh cocatalyst at the edges of nanoplates, resulting in spatial charge separation and significant enhancement of the photocatalytic activity.

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Various treatments have been used to treat chronic immune thrombocytopenic purpura in children; however, none of it has been established as the standard of care. The administration of thrombopoietin receptor agonists (TPO-RAs) has been approved as a new treatment option in Japan. In this case series, TPO-RAs were administered to 16 patients (eltrombopag, n=9; romiplostim, n=7).

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Trio-next generation sequencing is useful to identify undiagnosed inherited diseases. We have attended a patient with trigenic // pathogenic variants, which caused two distinct diseases, myelodysplastic syndrome and Usher syndrome. Whole genome sequencing of peripheral blood from the patient and his parents were applied to identify disease-causing genes.

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The development of semiconductors with narrow band gap and high stability is crucial for achieving solar to chemical energy conversion. Compounds with iodine, which has a high polarizability, have attracted attention because of their narrow band gap and long carrier lifetime, as typified by halide perovskite solar cells; however, they have been regarded as unsuitable for harsh photocatalytic water splitting because iodine is prone to self-oxidation. Here, we demonstrate that BaBiNbOI, a layered Sillén-Aurivillius oxyiodide, not only has access to a wider range of visible light than its chloride and bromide counterparts, but also functions as a stable photocatalyst, efficiently oxidizing water.

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The performance of photoelectrodes is hugely affected by the preparation method. Although a flux synthesis is useful to endow semiconductor particles with the desired properties such as high crystallinity, there are only a few reports on its application to photoelectrode fabrication, probably because relatively high temperatures are necessary. In the present study, we introduce a new concept for on-site flux synthesis of semiconductor crystals on a commonly used fluorine-doped tin oxide (FTO) substrate; a seed layer is predeposited and then treated with an appropriate flux containing other required elements at a right temperature lower than the limit temperature of FTO but sufficiently high to transform the seed layer to the target material with the aid of flux.

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Gilteritinib is an FMS-like tyrosine kinase 3 (FLT3) inhibitor that has shown efficacy in patients with refractory or recurrent adult acute myeloid leukemia (AML) with FLT3 mutations. However, there are limited data for pediatric patients treated with this drug. Herein, we report the clinical courses of two children with FLT3-mutated recurrent AML who received gilteritinib.

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An oxyhalide photocatalyst BiNbOCl has recently been proven to stably oxidize water under visible light, enabling the Z-scheme water splitting when coupled with another photocatalyst for water reduction. We herein report the synthesis of BiNbOCl particles via a flux method, testing various molten salts to improve its crystallinity and hence photocatalytic activity. The eutectic mixture of CsCl/NaCl with a low melting point allowed the formation of single-phase BiNbOCl at as low as 650 °C.

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Visible light-driven water splitting using cheap and robust photocatalysts is one of the most exciting ways to produce clean and renewable energy for future generations. Cutting edge research within the field focuses on so-called "Z-scheme" systems, which are inspired by the photosystem II-photosystem I (PSII/PSI) coupling from natural photosynthesis. A Z-scheme system comprises two photocatalysts and generates two sets of charge carriers, splitting water into its constituent parts, hydrogen and oxygen, at separate locations.

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Haploidentical hematopoietic cell transplantation (HCT) conditioning with clofarabine and target area under the blood concentration-time curve (AUC)-based busulfan adjustment was performed in three patients with refractory pediatric leukemia. The target AUC for two patients who had already received multiple transplantations was 3600 and 4000 μmol min/L, and that for the patient with Down's syndrome was 3000 μmol min/L. Regimen-related toxicity was well tolerated in all cases.

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In the present study, a polyoxometalate is for the first time applied as a shuttle redox in two-step (Z-Scheme) photocatalytic water splitting. Photocatalytic H2 evolution using a Mn-substituted polyoxometalate [SiW11 O39 Mn(II) (H2 O)](6-) as an electron donor proceeded over a Ru-loaded SrTiO3 :Rh photocatalyst under visible light with relatively high selectivity, accompanied by the stoichiometric production of its oxidized form [SiW11 O39 Mn(III) (H2 O)](5-) . Photocatalytic O2 evolution using the oxidized [SiW11 O39 Mn(III) (H2 O)](5-) as an electron acceptor proceeded over PtOx -loaded WO3 photocatalyst under visible light with relatively high quantum efficiency and selectivity, whereas the loading of effective PtOx cocatalyst was necessary to facilitate the reduction of polyoxometalate.

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ATF7IP-PDGFRB is a novel PDGFRB-related fusion gene identified in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) with a signature similar to that of Ph1 ALL, so-called Ph-like ALL. When we introduced ATF7IP-PDGFRB, murine Ba/F3 cells acquired the ability to proliferate in an interleukin (IL)-3-independent manner. On the contrary, the expression of wild-type PDGFRB is not sufficient to acquire the ability for IL-3-independent proliferation in Ba/F3 cells.

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Objective: We describe the clinical course and amplitude-integrated EEG findings in three children with non-accidental head injury and discuss on the importance of continuous aEEG monitoring in infants.

Methods: NCSE was defined as a continuous 30-min seizure or briefer seizures occurring consecutively comprising at least 30 min of any 1-h period. Non-accidental head injury was diagnosed on the basis of neuroimaging findings such as subdural hemorrhage.

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We introduced SNX2-ABL1, a novel ABL1-related chimeric transcript lacks SH3 and SH2 domains, into murine Ba/F3 cells and compared their function with that of BCR-ABL1. After the expression of SNX2-ABL1 proteins, Ba/F3 cells acquired an ability to proliferate in an IL-3-independent manner. Upon treatment with both imatinib and dasatinib, BCR-ABL1-expressing Ba/F3 cells underwent rapid apoptosis, whereas SNX2-ABL1-expressing Ba/F3 cells showed poorer sensitivity toward these TKIs and could proliferate in the presence of a low dose of dasatinib.

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Upon analyzing 696 childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL) cases, we identified the characteristics of CD66c expression. In addition to the confirmation of strong correlation with BCR-ABL positivity and hyperdiploid, we further observed that CD66c is frequently expressed in CRLF2-positive (11/15, p<0.01 against chimeric gene-negative) as well as hypodiploid cases (3/4), whereas it is never expressed in ETV6-RUNX1, MLL-AF4, MLL-AF9, MLL-ENL, and E2A-PBX1-positive cases.

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In addition to BCR, various rare fusion partners for the ABL1 gene have been reported in leukemia. We have identified the fusion gene SNX2-ABL1 in a pediatric case of acute lymphoblastic leukemia (ALL), which has only once previously been reported in an adult patient. Cytogenetic analysis detected this fusion gene arising from a t(5;9)(q22;q34) translocation.

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Insulin-like growth factor-1 (IGF-1) is known to be a major growth factor with effects on various cell types, including hematopoietic cells, as well as neoplasms, and is regulated by IGF-binding proteins (IGFBPs). In this study, we investigated the effects of IGF-1 on B-cell precursor acute lymphoblastic leukemia (BCP-ALL) cells. When the expression of IGF-1R in clinical samples of BCP-ALL was examined, five of thirty-two cases showed IGF-1R expression, whereas IGF-1R was expressed in most BCP-ALL cell lines.

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