Publications by authors named "Umemura M"

Fas ligand (FasL) has been well characterized as a death factor. However, recent studies revealed that ectopic expression of FasL induces inflammation associated with massive neutrophil infiltration. We previously demonstrated that the neutrophil infiltration-inducing activity of FasL is partly dependent on, but partly independent of, IL-1beta.

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The haem-distal pocket of nitric oxide reductase cytochrome P450 contains many Arg and Lys residues that are clustered to form a putative access channel for NADH. Asp88 is the sole negatively charged amino acid in this positive charge cluster, and thus it would be interesting to know its functional role. Here we found the intriguing phenomenon that mutation at this site of P450nor (D88A or D88V) considerably decreased the overall nitric oxide reductase activity without blocking the reducing half reaction in which the ferric enzyme-NO complex is reduced with NADH to yield a specific intermediate (I).

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Objective: Gentamicin (GM) has been used to ablate the vestibular system function as a form of treatment for Ménière's disease. Generally, clinicians have not recognized that commercial GM comprises three major compounds--GM-C1, -C2 and -C1a--and the effects of the individual compounds on the inner ear have not been elucidated. In this study we investigated differences in cochleo- and vestibulotoxicity between the three compounds

Material And Methods: Hartley guinea pigs were treated for 2 weeks with daily subcutaneous injections (100 mg/kg) of the GM complex or the GM-C1, -C2 or -C1a compounds.

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Cholesterol crystal embolism (CCE) is caused by the shedding of cholesterol crystals into the bloodstream, and it has been recently recognized as a serious complication after vascular procedures. Our case of CCE, which was diagnosed by skin and renal biopsies, occurred in a patient with hypertension and diabetes mellitus, 3 months after coronary angiography, with the development of renal failure and blue toes. After low-density lipoprotein apheresis (LDL-A), the skin lesions, including livedo reticularis and pain from the acrocyanotic toes, dramatically improved, with partial recovery of renal function.

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Interleukin-15 (IL-15) transgenic mice which had been inoculated with Mycobacterium bovis bacillus Calmette-Guérin (BCG) 24 weeks previously showed resistance against airborne infection with Mycobacterium tuberculosis H37Rv accompanied by an increased CD8(+)-Tc1-cell response. IL-15 may be used as an immune adjuvant given with BCG vaccination to enhance its biologic efficacy.

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Antigenic stimulation activates T cells and simultaneously destines them to die by Fas-mediated apoptosis. In this study, we demonstrated that various pathogen-associated molecular patterns up-regulated Fas expression in macrophages and sensitized them specifically to Fas ligand (FasL), but not to other apoptosis-inducing agents such as TNF-alpha, etoposide (VP-16), and staurosporine. Toll-like receptor, NF-kappaB, and p38 mitogen-activated protein kinase mediated these responses.

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Glycosylphosphatidylinositol (GPI) is a conserved post-translational modification to anchor cell surface proteins to plasma membrane in all eukaryotes. In yeast, GPI mediates cross-linking of cell wall mannoproteins to beta1,6-glucan. We reported previously that the GWT1 gene product is a target of the novel anti-fungal compound, 1-[4-butylbenzyl]isoquinoline, that inhibits cell wall localization of GPI-anchored mannoproteins in Saccharomyces cerevisiae (Tsukahara, K.

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IL-22 is a newly identified member of the interferon/IL-10 family. In humans, IL-22 signals through a heteroduplex receptor consisting of IL-22R and CRF2-4/IL-10Rbeta. To investigate the physiological function of IL-22 and IL-22R, we isolated a cDNA encoding the mouse IL-22R, which has been a missing component of the functional receptor complex for mouse IL-22.

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LP-BM5 murine leukemia virus (MuLV) infection causes murine acquired immunodeficiency syndrome (MAIDS), a disease characterized by varied functional abnormalities of immunocompetent cells. We found that MAIDS progression was severely retarded in IL-15 transgenic (Tg) mice constructed with cDNA encoding secretable IL-15 under the control of an MHC class I promoter. Several immune defects, including impaired natural killer activity, depressed IFN-gamma production by T cells stimulated with anti-T cell receptor cross-linking, and increased susceptibility to Mycobacterium bovis infection, were prevented in IL-15 Tg mice inoculated with LP-BM5 MuLV.

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Background & Aims: Toll-like receptors (TLRs) for bacterial constitutes are expressed not only by phagocytes but also by some subsets of T cells. We previously reported that natural killer T cells (NKT cells) play an important role in liver injury induced by Salmonella infection. In the present study, we investigated whether TLRs on NKT cells are involved in Salmonella-induced liver injury.

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By considering three kinds of music and noise, this research investigates the influence of music on the living body by comparing the difference of influence on heart rate variability and comfort when subjects listen to music and are exposed to noise. We used two pieces of classical music, rock music, and noise recorded by a tape recorder. The following conclusions were made from the findings of the research: 1) Hearing classical music results in a small variance of Mayer Wave related Sinus Arrhythmia (MWSA) component and Respiratory Sinus Arrhythmia (RSA) component compared with a body being at rest.

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To investigate the immunomodulating effects of IL-15 in vivo on mycobacterial infection, we used IL-15-transgenic (Tg) mice, which were recently constructed with cDNA-encoding secretable isoform of IL-15 precursor protein under the control of a MHC class I promoter. The IL-15-Tg mice exhibited resistance against infection with Mycobacterium bovis bacillus Calmette-Guérin (BCG), as assessed by bacteria growth. IFN-gamma level in serum was significantly higher in IL-15-Tg mice than in non-Tg mice after BCG infection.

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Recently, there have been many reports describing the efficacy of intratympanic aminoglycoside injection for the treatment of intractable vertigo in patients with Ménière's disease. However, the number of injections and the amount of drug injected varies, with concomitant variation in the side-effect of hearing deterioration. To identify drugs that are more selectively vestibulotoxic, we have reviewed the ototoxicity of aminoglycosides, focusing on differences between vestibulo- and cochleotoxicity.

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LP-BM5 murine leukemia virus (MuLV) injection causes murine AIDS (MAIDS), a disease characterized by many functional abnormalities of immunocompetent cells. We show that MAIDS mice are susceptible to Mycobacterium bovis Bacille Calmette-Guérin (BCG) infection as assessed by survival rate and bacterial counts. The peritoneal exudate macrophages from MAIDS mice produced a significant level of interleukin (IL)-12 soon after inoculation with BCG, whereas IL-15 and tumor necrosis factor (TNF) production were severely impaired in BCG-infected MAIDS mice.

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To investigate whether superantigen (SAG) from endogenous mouse mammary tumor virus functions as an immunogenic or a tumorigenic factor in tumor development, the BALB/c myeloma cell line FO was transfected with the SAG gene from the 3' Mtv-50 long terminal repeat (LTR) open reading frame (ORF), the product of which was specific for Vbeta6. All five transfectants expressing Mtv-50 LTR ORF mRNA showed stimulatory activity for Vbeta6 T-cell hybridomas in vitro; this activity was inhibited by the addition of anti-Mtv-7 monoclonal antibody (MAb) or anti-major histocompatibility complex class II I-A(d) and I-E(d) MAb. All transfectants with the SAG gene grew more rapidly than did mock transfectants in BALB/c mice after subcutaneous inoculation, whereas all clones, including mock transfectants, grew equally well in athymic nude mice.

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At least two types of interleukin (IL)-15 mRNA isoforms are generated by alternative splicing at the 5' upstream of exon 5 in mice. To elucidate the potential roles of IL-15 isoforms in immune responses in vivo, we constructed two groups of transgenic mice using originally described IL-15 cDNA with a normal exon 5 (normal IL-15 transgenic [Tg] mice) and IL-15 cDNA with an alternative exon 5 (alternative IL-15 Tg mice) under the control of an MHC class I promoter. Normal IL-15 Tg mice constitutionally produced a significant level of IL-15 protein and had markedly increased numbers of memory type (CD44(high) Ly6C(+)) of CD8(+) T cells in the LN.

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An analytical method for the determination of cardiac glycosides in Digitalis lanata leaves by reversed-phase thin-layer chromatography (RP-TLC) was developed. The procedure consisted of extraction of dry leaf powder with 50% methanol and clean-up by Sep-Pak cartridges prior to RP-TLC analysis. RP-TLC was performed on an octadecylsilyl bonded silica gel plate, using a developing solvent of acetonitrile-methanol-0.

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The senescence-accelerated mouse (SAM) has been established as a murine model of accelerated aging. We investigated learning ability and memory in various tasks in a SAM strain, SAMP1TA, and in a control strain of SAMR1TA at the ages of 20, 30 and 40 weeks. We also measured choline acetyltransferase (ChAT) and cholinesterase (ChE) activity in the brains of these mice at the same ages.

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This study clarifies the characteristics of the time keys that are taken to enter Roman letters for Japanese sentences. First, test the appearance frequency of two consecutive characters of the alphabet in the input of English sentences and in the input of the Roman characters of Japanese sentences. Based on these results, we analyzed the features of stroke frequency of the keys in the Roman character input.

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Titanium sponges were infused with bone morphogenetic protein (BMP-Ti), and the osteoinductivity of the resultant composite was measured. New bone formation occurred three weeks after implantation and was identified by soft x-ray analysis. Quantitative analysis showed no significant difference between BMP-Ti composites and control samples (BMP only).

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In the present study, we investigated the correlation between the physiological function, heart rate (HR) and the quantity of work performed when A-weighted sound pressure level of factory noise or construction noise was varied during the mental operations of calculation and erosion. Furthermore, we looked for differences in the effects of sound noise and music on the quantity of work performed. The A-weighted sound pressure level was set at four levels of background noise, i.

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There are two different treatments for condyle neck fracture. One is non-surgical treatment involving intermaxillary fixation, and the other is radical surgical treatment through various techniques, but it is difficult to discuss the relative merits. The purpose of this report is to decide whether surgical treatment is necessary, by comparing the two types of treatment.

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The complex-forming abilities of 2,6-di-O-ethyl-beta-cyclodextrin (DE-beta-CD), and its effect on the release of nitroglycerin (TNG) from formulations of the compound, were studied and compared with corresponding properties of beta-cyclodextrin (beta-CD) and 2,6-di-O-methyl-beta-cyclodextrin (DM-beta-CD). Complex formation was confirmed by differential scanning calorimetry and infrared absorption spectroscopy. In an accelerator test involving temperature and reduced pressure, marked depression of the volatility of TNG was observed as a result of CD complex formation.

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Bone morphogenetic protein (BMP) is known to be a protein which induces new bone at heterotopic sites. Purification of BMP has not been perfected, and obtaining large amounts of BMP is very difficult, so it seems better to use some carrier or frame material for BMP to work effectively. Various kinds of hydroxyapatite (HAP) have been used to repair periodontal osseous defects, but they do not have osteogenetic or osteoinductive properties.

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