Publications by authors named "Mutsumi Yamamoto"

This study aimed to clarify the relationship between the sequential organ failure assessment (SOFA) score and the length of intensive care unit (ICU) and hospital stays and verify whether the SOFA score can indicate the optimal length of ICU stay. Medical resource input was evaluated as the medical treatment score, converted by volume, within 2 days after ICU admission. After classifying emergency patients into surgical and nonsurgical categories, the relationship between medical resources, SOFA score, and ICU and hospital stay lengths was analyzed.

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Th1 and Th2 polarization is determined by the coordination of numerous factors including the affinity and strength of the antigen-receptor interaction, predominant cytokine environment, and costimulatory molecules present. Here, we show that Schnurri (SHN) proteins have distinct roles in Th1 and Th2 polarization. SHN2 was previously found to block the induction of GATA3 and Th2 differentiation.

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IL-2 is a growth factor for activated T cells and is required for maintenance of naturally arising regulatory T cells (nTregs). Mice defective in IL-2/IL-2 receptor signaling pathways have impaired nTregs and suffer from lymphoproliferative disorders, suggesting that IL-2 is present and functional in healthy animals. However, the cellular source of IL-2 is currently unknown.

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The expression of the pre-B cell receptor (BCR) is confined to the early stage of B cell development, and its dysregulation is associated with anomalies of B-lineage cells, including leukemogenesis. Previous studies suggested that the pre-BCR signal might trigger the autonomous termination of pre-BCR expression even before the silencing of pre-BCR gene expression to prevent sustained pre-BCR expression. However, the underlying mechanism remains ill defined.

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Recently, the environment of medical treatment in our country has become more strict. The purpose of this study is to find changes in the implementation of diagnostic imaging from the point of view of cost analysis, through the use of diagnosis procedure combination (DPC) data. The patient data has been extracted from the DPC data.

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Ag receptor stimulation of preactivated T cells causes rapid cell death in an IL-2- and Fas-dependent manner. This phenomenon, known as activation-induced cell death (AICD), plays a pivotal role in the removal of Ag-reactive T cells after initial expansion. In this study, we report a novel form of T cell apoptosis that is distinct from classic AICD.

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Pre-B-cell leukemia spontaneously develops in BLNK-deficient mice, and pre-B-cell acute lymphoblastic leukemia cells in children often lack BLNK protein expression, demonstrating that BLNK functions as a tumor suppressor. However, the mechanism by which BLNK suppresses pre-B-cell leukemia, as well as the identification of other genetic alterations that collaborate with BLNK deficiency to cause leukemogenesis, are still unknown. Here, we demonstrate that the JAK3/STAT5 signaling pathway is constitutively activated in pre-B leukemia cells derived from BLNK(-/-) mice, mostly due to autocrine production of IL-7.

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Pre-B cell receptor (pre-BCR) signals promote pre-B cell differentiation, in which the adaptor protein B-cell linker (BLNK) plays a crucial role. However, the molecular pathways downstream of BLNK are currently unclear. Utilizing pre-B leukemia cell lines (BKO84 and others) derived from BLNK-deficient mice as in vitro models of the pre-B cell differentiation, we have demonstrated that reconstitution of BLNK as well as an active form of protein kinase C (PKC)eta induces the differentiation events, such as pre-BCR down-regulation and kappa gene rearrangement.

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The pre-B-cell receptor (pre-BCR) is thought to signal transcriptional activation of the immunoglobulin light (L) chain gene locus, proceeding to its V-J rearrangement. The pre-BCR signaling pathway for this process is largely unknown but may involve the adaptor protein BASH (BLNK/SLP-65). Here we report that the pre-B leukemia cell lines established from affected BASH-deficient mice rearrange kappaL-chain gene locus and down-regulate pre-BCR upon PMA treatment or BASH reconstitution.

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Signaling through the B cell antigen receptor (BCR) induces activation and proliferation of B cells, a response that requires the adaptor protein BASH (also known as BLNK/SLP-65). Although BASH and other molecules, such as Btk, PLCgamma2 and PKCbeta, are known to be essential for T cell-independent immune responses in vivo, their requirement during T cell-dependent immune responses, especially their role in antibody affinity-maturation and memory B cell generation remains unclear. In this study, we examined primary and memory immune responses to the T cell-dependent hapten antigen, (4-hydroxy-3-nitrophenyl)acetyl (NP) conjugated to chicken gammaglobulin (CGG), in BASH-deficient mice on a C57BL/6 background.

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The pre-B cell receptor triggers expansion and differentiation of pre-B cells (the pre-B cell transition), as well as inhibition of V(H) to DJ(H) recombination (allelic exclusion). The latter also accounts for counter-selection of pro-B cells expressing Dmu protein (Dmu selection). However, the signaling pathways responsible for these events remain poorly defined.

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