Publications by authors named "Yashiki T"

We perform friction experiments between a compliant gel and a rigid cylinder at sliding velocities comparable to the Rayleigh wave or secondary wave velocity of the gel. We find that, when the sliding velocity exceeds the wave velocities, the contact state transitions from Hertzian like to flat punch like, resulting in the breakdown of the lubricating oil film and the abrupt increase in the friction coefficient. We succeed in deriving theoretical solutions for the contact pressure distributions and the deformation profiles in the presence of friction, which are consistent with our experimental observations.

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Background/aims: Extracellular vesicles (EVs), including exosomes, are present in various bodily fluids, including urine. We and others previously reported that cells expressing fibroblast-specific protein 1 (FSP1) accumulate within damaged glomeruli, and that urinary FSP1, as well as urinary soluble CD163, could potentially serve as a biomarker of ongoing glomerular injury.

Methods: To test that idea, we collected urine samples from 37 patients with glomerular disease; purified the urinary EVs; characterized them using Nanosight, western blotting, and immunoelectron microscopy; and determined FSP1 and soluble CD163 levels using enzyme-linked immunosorbent assays.

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Lipid-binding properties and/or involvement with host defense are often found in allergen proteins, implying that these intrinsic biological functions likely contribute to the allergenicity of allergens. The group 2 major mite allergens, Der f 2 and Der p 2, show structural homology with MD-2, the lipopolysaccharide (LPS)-binding component of the Toll-like receptor (TLR) 4 signalling complex. Elucidation of the ligand-binding properties of group 2 mite allergens and identification of interaction sites by structural studies are important to explore the relationship between allergenicity and biological function.

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Vascular endothelial growth factor (VEGF) is a positive regulator and plays a crucial role in angiogenesis. We demonstrate that VEGF was highly expressed in cultures of human bone marrow-derived mesenchymal stem cells (hMSCs) and the high expression level was maintained during prolonged culture periods (checked up to passage 10). We also confirmed that in vivo hMSCs engrafted into immunodeficient mice could survive and secreted human VEGF.

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We have succeeded in raising highly specific anti-human intestinal fatty acid-binding protein (I-FABP) monoclonal antibodies by immunizing animals with three synthetic regional peptides, i.e., the amino terminal (RP-1: N-acetylated 1-19-cysteine), middle portion (RP-2: cysteinyl-91-107) and carboxylic terminal (RP-3: cysteinyl-121-131) regions of human I-FABP, and the whole I-FABP molecule as antigens.

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Measurement of serum sultopride levels was performed using an enzyme immunoassay. Little or no cross-reactivity with metabolites of sultopride and other drugs was found. The results of reproducibility, recovery, and dilution testing were all good enough for clinical use.

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Unlabelled: Carbon dioxide (CO2) laser vaporization for turbinate has rapidly gained acceptance in Japan for the treatment of allergic rhinitis.

Objective: The aim of this study was to examine the effects of laser output, patient age, and the presence of a deviated nasal septum on treatment outcome in patients with intractable allergic rhinitis.

Methods: The inferior turbinates were irradiated at an output of 3 or 5 W for 0.

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Some viruses seem to be capable of suppressing interferon (IFN)-induced 2',5'-oligoadenylate synthetase (2-5AS) induction. Cells infected with human T-lymphotropic virus type-I (HTLV-I) show different natures for the constitutive production of IFN-gamma or sensitivity to IFN. Poor induction of 2-5AS was found in IFN-gamma producer cells carrying HTLV-I (MT-1, MT-2 and SMT-1).

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A sensitive high-performance liquid chromatographic (HPLC) method is described for the determination of a new potent antihypertensive agent, TCV-116, and its two metabolites (M-I and M-II) in human serum or urine. After pre-treatment of the specimens, the analytes were determined using a column switching technique, except for the metabolites in urine which were determined by gradient elution mode HPLC. The quantitation limits for TCV-116, M-I and M-II were all 0.

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Poor induction of interferon-induced 2', 5'-oligoadenylate synthetase (2-5AS) activity has been demonstrated in cells persistently infected with the mumps virus or human T-lymphotropic virus type-I (HTLV-I). The suppression of 2-5AS induction is the result of the repression of 2-5AS gene expression at the transcription level. In a general way, after the binding of interferon-alpha (IFN-alpha) to cell surface-specific receptors, expression of 2-5AS gene is thought to be regulated by some transacting factors, IFN-regulatory factors (IRF-1 and IRF-2) and the IFN-stimulated gene factor (ISGF-3, a complex consisting of STAT-1 alpha, STAT-2 and p48).

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Persistent infections with mumps virus were established in several human lymphoid cells of T-cell origin (Molt-4, TALL-1, and CCRF-CEM) and human monocyte cells (U937 and THP-1). 2',5'-Oligoadenylate synthetase (2-5AS) activity was demonstrated to be only slightly induced by interferon (IFN) or TPA (12-O-tetradecanoyl-phorbol-13-acetate) treatment in these cells. Treatment of the persistently infected cells with IFN or TPA did not stimulate an increase in the amount of synthetase mRNA.

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A high-performance liquid chromatographic method was developed for the sensitive determination of methotrexate (MTX) in monkey plasma using direct injection and on-line solid-phase extraction. After application of a 100-microliters aliquot of plasma to a pre-treatment column, the column was washed with 0.02 M phosphate buffer (pH 7) to eliminate plasma proteins and endogenous substances, and subsequently the adsorbed MTX was eluted.

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A method for the determination of total phenylephrine (free plus conjugated) in human serum was developed using column-switching high-performance liquid chromatography (HPLC) with fluorescence detection. After serum was deproteinized with acetonitrile, the conjugated phenylephrine was hydrolyzed with diluted hydrochloric acid. The solution was evaporated to dryness.

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A sensitive method for the determination of chlorpheniramine in human serum was developed using column-switching high-performance liquid chromatography (HPLC) with ultraviolet detection at 210 nm. The analyte was extracted with diethyl ether from alkalinized serum. After evaporation of the organic layer, the reconstituted residue was analyzed by HPLC using a heart-cut technique.

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A high-performance liquid chromatographic (HPLC) method is described for the determination of busulfan in human serum using on-line derivatization and column switching. Busulfan was extracted from serum with a mixture of diethyl ether and dichloromethane. After the evaporation of the organic layer, the reconstituted residue was injected into the HPLC system and busulfan was derivatized with sodium diethyldithiocarbamate on the first short column.

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A sensitive high-performance liquid chromatographic (HPLC) method using column switching is described for the determination of EM523 (I), a new erythromycin derivative, in human plasma and urine. The analyte was extracted from alkalinized plasma or urine with a mixture of n-hexane and acetone. After the evaporation of the organic layer, the reconstituted residue was injected into the HPLC system and separated on the first column.

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A high-performance liquid chromatographic method for the sensitive determination of 2,2'-[(2-aminoethyl)imino]diethanol bis(butylcarbamate) (I) and its metabolites in human serum has been developed. The method was based on a pre-column derivatization with o-phthalaldehyde. The derivatives were stabilized at least for 24 h at 4 degrees C by using N-acetyl-L-cysteine as a thiol and by eliminating the excess o-phthalaldehyde in the reaction mixture by solvent extraction and the addition of an ammonium salt after the reaction.

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We have analysed the genes borne on a 6.0 kb HindIII fragment cloned from the chromosome of Clostridium botulinum type E strain Mashike. This fragment, cloned within plasmid pU9EMH, contains part of the structural gene for botulinum toxin type E neurotoxin as well as the entire structural gene for a nontoxic component of botulinum type E progenitor neurotoxin gene, ent-120.

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The complete nucleotide and deduced amino acid sequence of the nontoxic component of botulinum type E progenitor toxin is determined in recombinant plasmid pU9BUH containing about 6.0 kb HindIII fragment obtained from chromosomal DNA of Clostridium butyricum strain BL6340. The open reading frame (ORF) of this nontoxic component gene is composed of 3,486 nucleotide bases (1,162 amino acid residues).

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N4-Aminocytidine is mutagenic in various organisms. In the cell, this cytidine analog is metabolized into N4-aminodeoxycytidine 5'-triphosphate, which will then be incorporated into DNA and mutation will result during the replication of the DNA. To prove that the N4-aminocytosine residue in DNA is indeed the site of mutagenesis, we prepared a series of phage M13mp2 DNA samples that bear N4-aminocytosine residues at a few defined positions in the lacZ alpha region, by carrying out in vitro limited extension of primed phage DNA.

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An automated high-performance liquid chromatographic method using column switching was established for the simultaneous determination of cefotiam (I) and delta 3-cefotiam (II) in human plasma after oral administration of cefotiam hexetil dihydrochloride. The method allowed the determination of analytes in plasma by the direct injection of diluted specimen with phosphate buffer. The analytes were enriched onto the C18 short pretreatment column by 0.

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A stereoselective and highly sensitive method using chiral chromatography and successive column-switching liquid chromatography is described for the determination of manidipine enantiomers in human serum. A human serum sample obtained after ingestion of manidipine was extracted twice with a mixture of n-hexane-diethyl ether under alkaline conditions. The enantiomers in the extract were separated on a chiral stationary phase column (Chiralcel OJ), and the effluents containing the respective enantiomers were collected.

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Chromosomal DNAs were extracted from Clostridium butyricum strain BL6340 and Clostridium botulinum type E strain Mashike. The 6.0 Kbp fragment coding for the entire light chain (L) component and the N-terminus of heavy chain (H) component of botulinum type E toxin was obtained from each extracted DNAs after digestion with HindIII.

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Spontaneous production of interferon-gamma (IFN-gamma) was shown in several T-lymphoblastoid cell lines persistently infected with human T-lymphotropic virus (HTLV-1). However, the produced IFN-gamma was not always associated with the induction of the antivirus state. The induction of oligo-2',5'-adenylate synthetase (2-5AS) by IFN was studied in five human T-cell lines persistently infected with HTLV-I (MT-1, MT-2, SMT-1, HUT 102 and OKM-2).

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