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R Yanagawa

Publications and source records attributed to R Yanagawa.

At least 73 records · Page 4Linked to original sources
PubMed1985

Characterization of a partially purified leptospiral genus-specific protein antigen.

A leptospiral genus-specific protein antigen (GP-Ag) was partially purified from Leptospira interrogans serovar kremastos strain Kyoto and canicola strain Hond Utrecht IV, by treating the organisms with Triton X-100 followed by a purification procedure including fractionation with DEAE-cellulose column chromatography and ethanol precipitation. Genus-specificity of the antigens from kremastos Kyoto and canicola was shown by the immunodiffusion (ID) test. Complement fixation (CF) test and enzyme-linked immunosorbent assay (ELISA) using GP-Ag from kremastos Kyoto showed the genus specificity of the GP-Ag. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of the antigens from kremastos Kyoto and canicola showed a major band with Coomassie blue stain. The band of GP-Ag from kremastos Kyoto was also shown by immunoprecipitation using the monoclonal antibody (GP-7) to GP-Ag from kremastos Kyoto. The molecular weight of the genus-specific antigen was estimated to be approximately 62 000. The genus specificity of the antigen was reduced by heating at 100 degrees C or treatment with proteolytic enzymes, but not reduced by treatment with sodium metaperiodate.

Agglutination Tests↗
PubMed1985

Detection of antibodies to leptospiral genus-specific antigen in human and animal sera by indirect hemagglutination test with a partially purified genus-specific protein antigen.

Antibodies against leptospiral genus-specific antigen were detected in the sera from clinically diagnosed human leptospirosis and suspected animal leptospirosis by indirect hemagglutination (IHA) test with a partially purified genus-specific protein antigen (GP-Ag). The reaction was positive in the infected humans and animals irrespective of the leptospiral serovars. No significant correlation was found between IHA titer against GP-Ag and microscopic agglutination (MA) titer. IHA titer did not always develop in parallel with MA titers. Sera obtained from healthy individuals were negative in both IHA and MA tests.

Animals↗
PubMed1985

Production of monoclonal antibodies against leptospiral genus-specific protein antigen and localization of the antigen by immunoelectron microscopy.

Monoclonal antibodies were first produced against a leptospiral genus-specific protein antigen (GP-Ag) isolated from Leptospira interrogans serovar kremastos strain Kyoto. The representative monoclonal antibody (GP-7) did not agglutinate kremastos Kyoto but reacted with Triton X-100 treated kreamastos Kyoto, andamana, patoc and Urawa in enzyme-linked immunosorbent assay (ELISA), indicating that the monoclonal antibody recognized the genus-specific determinant of GP-Ag. The localization of GP-Ag was investigated by immunoelectron microscopy with the iodinated antibody and peroxidase-labeled antibody. The genus-specific determinant of GP-Ag recognized by GP-7 was located on the subsurface of the leptospiral envelope.

Animals↗
PubMed1985

Adhesion of Corynebacterium pilosum by pili to epithelial cells of bovine vulva.

Piliated (P+) and nonpiliated (P-) clones of Corynebacterium pilosum were selected, and their adhesion to the epithelial cells of the bovine vulva and vaginal vestibule was examined. The number of P+ bacteria of C pilosum that adhered to vulval epithelial cells was greater than that of P- bacteria. The adhesion of P+ bacteria, but not P- bacteria, to the epithelial cells was inhibited by the antipilus antiserum; therefore, the adhesion of C pilosum to the epithelial cells of the vulva was primarily dependent on the pili. The number of C pilosum that adhered to the epithelial cells of the bovine vulva and of the vaginal vestibule increased by decreasing the pH.

Adhesiveness↗
PubMed1985

Adhesion of Corynebacterium renale and Corynebacterium pilosum to epithelial cells of bovine vulva.

Corynebacterium renale and C pilosum adhered effectively to the epithelial cells of the bovine vulva; the numbers of these organisms that adhered to the vulval epithelial cells were 50 and 30/cell, respectively, which were several times as many as those that adhered to the uroepithelial cells. Of the epithelial cells of the vulva, cornified cells lacking nuclei bound more bacteria than did those with indistinct nuclei, indicating that adhesion of bacteria was most effective to the most aged cells. The marked adhesion of C renale and C pilosum to the epithelial cells of the vulva may indicate that the vulva is an important portal of entry of these bacteria.

Adhesiveness↗
PubMed1984

Leptospiral attachment to cultured cells.

Each virulent strain of copenhageni, canicola and pomona of Leptospira interrogans attached effectively to MDCK cells and primary dog kidney cells, while the avirulent or less virulent line of the same strain and avirulent strains belonging to the same serovars and the avirulent reference strains of other serovars did not. Inhibition of the attachment of the virulent copenhageni to MDCK cells was found in the presence of the homologous immunoglobulin G Fab fragment. Strains of L. biflexa attached to the animal cells, but they differed from those of virulent L. interrogans in their capability to attach to glass.

Adhesiveness↗
PubMed1984

Isolation of an antigenic oligosaccharide fraction from Leptospira interrogans serovar canicola with a monoclonal antibody.

An oligosaccharide fraction containing the antigenic determinant of lipopolysaccharide antigen (TM antigen) from Leptospira interrogans serovar canicola, recognized by a monoclonal antibody (CT3) which agglutinates serovars canicola and broomi, was isolated by formic acid and successive sulphuric acid hydrolyses. Separation of the antigenic compounds was done by Bio-Gel P-2 and Sephadex G-25 gel filtration, and high-performance liquid chromatography with two different columns. The fraction finally obtained was a mixture of two oligosaccharides, both of which migrated as a single spot having a slightly higher mobility than an authentic tetrasaccharide (stachyose) on thin layer chromatography. The fraction contained rhamnose, arabinose and two major and two minor unknown sugars which were shown to be N- or O-acetylated and/or O-methylated sugars by nuclear magnetic resonance. The fraction inhibited the binding of CT3 antibody with TM antigen in enzyme-linked immunosorbent assay and microscopic agglutination of serovar canicola with the antibody. The inhibitory activity was destroyed by periodate oxidation or mild alkaline treatment, but was resistant to sodium borohydride reduction.

Antibodies, Monoclonal↗
PubMed1984

Restriction endonuclease DNA analysis of Leptospira interrogans serovars icterohaemorrhagiae and hebdomadis.

Antigenic variants of Leptospira interrogans serovars copenhageni and hebdomadis were examined by bacterial restriction endonuclease DNA analysis with EcoRI, XhoI, SalI, BstEII, and HindIII as the digesting enzymes. The antigenic variants were stable cloned strains which had been cultivated in media containing homologous immune serum. One of the strains examined has been reported elsewhere (R. Yanagawa and J. Takashima, Infect. Immun. 10:1439-1442) as having an antigenic makeup which more closely resembles serovar kremastos than the serovar hebdomadis parent. The closely antigenically related but naturally occurring serovars icterhaemorrhagiae strain RGA and copenhageni strain M20 were examined in parallel. No differences could be shown between the hebdomadis parent and any of its mutants. Serovars copenhageni and icterohaemorrhagiae produced patterns which differed in the high-molecular-weight bands only. The Shibaura parent strain did not differ from copenhageni M20, but the Shibaura M1 strain differed from the other mutants and from icterohaemorrhagiae RGA in its high-molecular-weight bands.

DNA Restriction Enzymes↗
PubMed1983

Inhibition of virus-induced hemolysis with monoclonal antibodies to different antigenic areas on the hemagglutinin molecule of A/seal/Massachusetts/1/80 (H7N7) influenza virus.

A/seal/Massachusetts/1/80 (H7N7) influenza virus caused maximal hemolysis at pH 5.9 Monoclonal antibodies to each of the four nonoverlapping antigenic areas on the hemagglutinin molecule of the virus inhibited the hemolysis whereas those belonging to two of the groups did not inhibit hemagglutination of the virus. Hemolysis also occurred when the virus was incubated at pH 5.9 prior to addition of erythrocytes. Such hemolysis caused by acid-treated virus was inhibited with the antibodies as well. At pH 5.9, hemagglutination of neither intact virus nor hemagglutinin rosettes was inhibited with any of the monoclonal antibodies, indicating conformational change in the hemagglutinin molecule, at this pH. On the other hand, hemagglutination-inhibition was observed when the antigens were incubated with the monoclonal antibodies at pH 7.0 and then the pH was later shifted to 5.9, suggesting that antibody-binding interferes with the conformational change in the hemagglutinin molecule at pH 5.9. The present findings indicate that antibodies to the hemagglutinin of influenza virus can inhibit virus-induced hemolysis by blocking conformational change in the hemagglutinin molecule and blocking later step of fusion than the conformational change, in addition to blocking attachment of virus to the receptor of erythrocytes.

Animals↗
PubMed1983

Human influenza virus infection in mink: serological evidence of infection in summer and autumn.

During the period from July to November 1981, 42 out of 128 young mink of a flock were found to possess antibodies against the viruses A/Bangkok/1/79 (H3N2) and A/Kumamoto/37/79 (H1N1), which were currently prevailing human influenza viruses. Seroconversion against A/Bangkok/1/79 was found in 12 mink from August to November. HI antibody titers of greater than 1: 128 were found in 8 out of 42 mink at the first examination in July and August. These findings suggest that infection with these human influenza viruses was present in this flock during the period from birth (the beginning of May) to autumn, the non-prevalent season in man. Attempts at virus isolation were unsuccessful.

Animals↗
PubMed1982

Adhesion of Corynebacterium renale, Corynebacterium pilosum, and Corynebacterium cystitidis to bovine urinary bladder epithelial cells of various ages and levels of differentiation.

The adhesion of Corynebacterium renale, Corynebacterium pilosum, and Corynebacterium cystitidis to various epithelial cell layers of bovine urinary bladders was examined. Adhesion was most efficient to the urinary sediment epithelial cells and the superficial cells immediately before shedding, followed by the remaining superficial cells and intermediate cells in this order, and least efficient to the deeper intermediate and basal cells. Incubation of the intermediate cells for 6 h increased the number of bacteria that adhered to these cells.

Age Factors↗