Publications by authors named "Hirotaka Kimura"

Phosphoinositides (PIPs) participate in many cellular processes, including cancer progression; however, the metabolic features of PIPs associated with prostate cancer (PCa) are unknown. We investigated PIPs profiles in PTEN-deficient prostate cancer cell lines, human prostate tissues obtained from patients with PCa and benign prostate hyperplasia (BPH) specimens using mass spectrometry. In immortalized normal human prostate PNT1B cells, PTEN deficiency increased phosphatidylinositol tris-phosphate (PIP) and decreased phosphatidylinositol mono- and bis-phosphate (PIP and PIP), consistent with PTEN's functional role as a PI(3,4,5)P 3-phosphatase.

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Objective: Neutrophil extracellular traps (NETs) are peculiar structures composed of the externalized chromatin with intracellular proteins and formed by activated neutrophils in a reactive oxygen species (ROS)-dependent manner. Aberrant NETs are considered to be autoantigens for anti-neutrophil cytoplasmic antibodies (ANCAs) underling the development of microscopic polyangiitis (MPA). However, little is known regarding the therapeutic efficacy of in vivo inhibition of NET formation (NETosis) on MPA pathogenesis.

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Hypertrophic cardiomyopathy (HCM) is a common heart disease with a prevalence of 1 in 500 in the general population. Several mutations in genes encoding cardiac proteins have been found in HCM patients, but these changes do not predict occurrence or prognosis and the molecular mechanisms underlying HCM remain largely elusive. Here we show that cardiac expression of vacuolar protein sorting 34 (Vps34) is reduced in a subset of HCM patients.

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Unlabelled: Inositol polyphosphate 4-phosphatase B (INPP4B) has been identified as a tumor suppressor mutated in human breast, ovary, and prostate cancers. The molecular mechanism underlying INPP4B's tumor-suppressive role is currently unknown. Here, we demonstrate that INPP4B restrains tumor development by dephosphorylating the PtdIns(3,4,5)P3 that accumulates in situations of PTEN deficiency.

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The lens of the eye is composed of fiber cells, which differentiate from epithelial cells and undergo programmed organelle degradation during terminal differentiation. Although autophagy, a major intracellular degradation system, is constitutively active in these cells, its physiological role has remained unclear. We have previously shown that Atg5-dependent macroautophagy is not necessary for lens organelle degradation, at least during the embryonic period.

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The metabolism of membrane phosphoinositides is critical for a variety of cellular processes. Phosphatidylinositol-3,5-bisphosphate [PtdIns(3,5)P(2)] controls multiple steps of the intracellular membrane trafficking system in both yeast and mammalian cells. However, other than in neuronal tissues, little is known about the physiological functions of PtdIns(3,5)P(2) in mammals.

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Objective: To determine levels of interleukin 33 (IL-33) in serum and synovial fluid (SF) and their clinical associations in patients with rheumatoid arthritis (RA). To evaluate the ability of activated peripheral blood mononuclear cells (PBMC) and fibroblast-like synoviocytes (FLS) from RA patients to release IL-33.

Methods: Sera were obtained from 59 patients with RA, 10 patients with infectious diseases, and 42 healthy volunteers.

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Background: In Western countries, several multicenter collaborative studies on acute myocardial infarction (AMI) have provided much information about this disease. In Japan, on the other hand, there have been few cohort studies in which a sufficient number of Japanese patients with AMI were registered during a short period. This fact explains the absence of a database from which strategies for treating Japanese patients with AMI could be established.

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A 39-year-old woman with mixed connective tissue disease suddenly developed repeated watery diarrhea two years after the onset of the disease. A colonic biopsy specimen revealed amyloid A protein deposition and the diagnosis of secondary amyloidosis was established. The amyloid deposition disappeared after the 8-month course of the treatment with prednisolone and azathioprine.

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This study evaluated the impact of serum creatinine levels on in-hospital mortality in 1,359 consecutive patients with acute myocardial infarction (from a Japanese prospective multicenter registry) who underwent successful primary percutaneous coronary intervention (PCI). Even in the patients who underwent successful primary PCI, the in-hospital mortality of patients with mild (1.2 View Article and Find Full Text PDF

To elucidate the relation between exercise capacity and peripheral hemodynamics in patients after the Fontan operation, near-infrared spectroscopy was performed on the vastus lateralis muscle, and flow-mediated vasodilation of the brachial and posterior tibial arteries was done with high-resolution ultrasonography. In Fontan patients, diminished exercise capacity was related to a reduced blood flow supply and an attenuated post-exercise oxygen resaturation of the working skeletal muscle, which also was related to impaired endothelium-dependent vasodilation.

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