Biomedical subjects

Y Yanagihara

Publications and source records attributed to Y Yanagihara.

At least 109 records · Page 6Linked to original sources

PubMed1994

Polymerase chain reaction analysis of Borrelia species isolated in Japan.

Primer reactivities of 25 Borrelia burgdorferi sensu lato isolates from the ticks, Ixodes persulcatus and I. ovatus, in Japan and 10 isolates in Europe and North America were investigated. The methods used in this study were the polymerase chain reaction (PCR) on the flagellin structural gene (fla), the outer surface protein A gene (osp A) and the outer surface protein B gene (osp B), and the restriction fragment length polymorphism (RFLP) analysis of PCR products from osp A and osp B. The flagellin PCR primer set reacted with all the Borrelia strains tested. Four genospecies, B. burgdorferi sensu stricto, B. garinii, B. afzelii and B. japonica, were differentiated by PCR using osp A and osp B primers combined with RFLP analysis. Some Japanese isolates from I. persulcatus were identified as B. garinii or B. afzelii. The other isolates from I. persulcatus did not fit in any of the 4 genospecies. These results suggested that Japanese isolates from I. persulcatus are highly heterogeneous in their osp A and osp B structures. Furthermore, PCR primers targeting fla are applicable to the gene diagnosis for Lyme disease in Japan, and osp A and osp B primers can be used to classify B. burgdorferi sensu lato isolates into genospecies by PCR and RFLP analyses.

Bacterial Outer Membrane Proteins↗

PubMed1994

Infectivity and early antibody response to Borrelia burgdorferi sensu lato isolated in Japan in outbred mice.

Borrelia burgdorferi sensu lato isolated from Ixodes ovatus (B. japonica), I. persulcatus and patients with erythema migrans (EM) in Japan were determined on infectivity and arthritis induction-activity in outbred mice. Infectivity of B. japonica was weak and did not induce the development of footpad swelling by subcutaneous (s.c.) inoculation into the footpad. Challenged strain, NO129-M of B. japonica, to ddY mice were reinoculated to the mice at various cell numbers (1 x 10-1 x 10(6) cells/mouse). The strain isolated from the mouse did not reinfect ddY mice and did not induce the production of specific antibody to the homologous strain. On the other hand, strains from I. persulcatus and patients with EM in Japan infected the mice and induced a serious inflammatory response in Borrelia-inoculated footpad as well as strains belonging to the three genospecies, B. burgdorferi sensu stricto, B. garinii, and B. afzelii, related to Lyme disease, from North America and Europe. The mice were infected with 10 cells of strain HP1 isolated from I. persulcatus in Hokkaido and of strain 297 isolated from a patient in the U.S.A. by subcutaneous inoculation into the hind footpad, or by intradermal inoculation into the back. Antigens of ca. 20, 23-24 (Osp C), 29, 39, 41 (flagellin) and 45 kDa reacted with the pooled sera from mice inoculated with strains HP1 and 297, but Osp A and Osp B did not.

Animals↗

PubMed1994

Allergen-specific human IgE helper T cell lines derived from patients allergic to Japanese cedar pollen.

To study the regulatory mechanism of allergen-dependent human IgE synthesis, Cry j I-specific and interleukin 4 (IL-4)-producing CD4+ T cell lines (SN-4 and SS-12) were established from 2 patients allergic to Japanese cedar pollen who highly expressed IL-4 mRNA in T cells in response to Cry j I stimulation. Upon stimulation of SN-4 and SS-12 cells with Cry j I, IL-4 production, which was observed at the protein and the mRNA levels, was induced in an HLA-DR-restricted manner, using autologous and allogeneic antigen-presenting cells. In addition to IL-4, not only considerable amounts of IL-5 and IL-6 but also very small amounts of IL-2 and interferon-gamma (IFN-gamma) were secreted by SN-4 and SS-12 cells, indicating that they fit into the Th2-like phenotype. The culture supernatant from Cry j I-activated SN-4 cells had the ability to induce IL-4-dependent IgE synthesis, CD23 expression and soluble CD23 release. Moreover, Cry j I-dependent IgE synthesis medated by SN-4 cells derived from 1 patient expressing HLA-DRw8, w9 could be specifically induced in both autologous and HLA-DRw9-matched allogeneic B cell cultures. This IgE induction was inhibited by neutralizing antibodies to IL-4, IL-5 and IL-6, but was not enhanced by anti-IFN-gamma antibody. On the other hand, neither IL-4 production nor IgE synthesis was induced when SN-4 cells were cocultured in the presence of Cry j I with HLA-DRw8-matched or histoincompatible allogeneic cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Recombinant soluble form of the human high-affinity immunoglobulin E (IgE) receptor inhibits IgE production through its specific binding to IgE-bearing B cells.

A recombinant soluble form of the alpha subunit of the human high-affinity receptor for IgE (rsFc epsilon RI alpha), one of the potent IgE-binding molecules, was tested for its ability to regulate IL-4-induced IgE synthesis by human lymphocytes. Addition of rsFc epsilon RI alpha to cultures induced a dose-dependent inhibition of the T cell-dependent and independent synthesis of IgE. The suppression of IgE synthesis was observed at the protein and the mRNA levels, and it was IgE class specific. By flow cytometry, specific binding of rsFc epsilon RI alpha was detected on surface IgE-bearing B cells as well as on U266 cells, and it was completely blocked by preincubation with IgE. rsFc epsilon RI alpha bound to the cell surface IgE could be effectively dissociated not only by a large excess of IgE, but also by an anti-rsFc epsilon RI alpha mAb that competes with IgE for the binding to rsFc epsilon RI alpha. This mAb abolished the rsFc epsilon RI alpha-mediated suppression of IgE synthesis. These data suggest that rsFc epsilon RI alpha may have a function in selectively suppressing IgE synthesis through its interaction with the membrane-bound form of IgE.

Adult↗

PubMed1994

DNA strand-breaking activities of quinolone antimicrobial agents under visible light irradiation.

The DNA strand-breaking activities of 9 quinolones, widely used as antimicrobial agents and suspected to induce photo-dermatological disorders in humans, were examined under irradiation using standard domestic fluorescent lamps. Two quinolones, tosufloxacin and enoxacin, converted the supercoiled covalently closed circular plasmid DNA to the open circular form under visible light irradiation. The maximum of photodynamic single strand-breaking activity for tosufloxacin was found to be 12% at 50 microM and that of enoxacin was 33% at a concentration of 2 mM. The DNA strand-breaking activities of photoirradiated tosufloxacin and enoxacin were markedly inhibited by NaN3 but only partially by D-mannitol, superoxide dismutase (SOD) and catalase did not inhibit these activities. These results suggest that some quinolone antimicrobial agents can be activated by visible light and induce phototoxic DNA damage in various organisms. We should carefully investigate such phototoxic activities during the development of new quinolones to avoid producing phototoxic disorders in man.

4-Quinolones↗

PubMed1994

Mitogenic activity and the induction of tumor necrosis factor by lipopeptide analogs of the N-terminal part of lipoprotein in the outer membrane of Escherichia coli.

Mitogenicity and the production of tumor necrosis factor (TNF) by a chemically synthesized lipotetrapeptide analog (KAB-8), S-[2,3-bis(palmitoyloxy)-2R-propyl]-N-[(2,2,2)-trichloro- ethoxycarbonyl: Troc group]-(R)-cysteinyl-(S)-seryl-(S)-seryl-(S)-asparagine, the amino acid sequence of which corresponds to that of the lipopeptide part of lipoprotein in Escherichia coli, and several derivatives (KAB-30-41), which possessed the altered glycerocysteine moiety, were examined. A 1-cysteinyl glycerol skeleton-type compound (KAB-8), a propane-type compound (KAB-31), a homoglycerol-type (KAB-39 and 40) and a 2-cysteinyl glycerol-type (KAB-41) exhibited mitogenic activity on splenocytes from C3H/He mice at various concentrations ranging from 0.4 to 100 micrograms/ml. However, propane-type compounds, except KAB-31, and ethane-type compounds showed lower mitogenic activity than other types of compounds. Compounds KAB-8, 31, 40 and 41 induced the production of TNF in peritoneal exudated macrophages from C3H/He mice at concentrations of 25 and 50 micrograms/ml. The results indicate that the structural differences of the glycerol moiety in the synthetic lipopeptides affect the potency of its biological activities.

Animals↗

PubMed1994

Nature of protein adsorption in artificial tear solution on plasma-irradiated polymethylmethacrylate surface.

To evaluate the effect of plasma treatment on protein adsorption onto a polymer surface, we carried out Ar plasma irradiation on polymethylmethacrylate (PMMA) plate and examined the adsorption behavior of protein after immersion of plasma treated PMMA plate in the artificial tear solution containing lysozyme, albumin and gamma-globulin. It was found that the total adsorption of protein in the artificial tear solution to PMMA is suppressed by the Ar plasma treatment. But the adsorption of each component protein differs according to the surface condition of polymers and obviously corresponds to the change with time in the surface wettability. It is concluded that introduction of a hydrophilic group into the PMMA surface by plasma treatment and coming off of it are associated with the adsorption behavior of proteins. Since the adsorption of protein to the plasma-treated PMMA surface changes over time, care should be exercised in determining it, when an attempt is made to clarify the effect of plasma irradiation on the adsorption to the plasma-irradiated polymer surface.

Adsorption↗

PubMed1994

Lyme disease spirochetes in a wild fox (Vulpes vulpes schrencki) and in ticks.

Lyme disease spirochetes were demonstrated in a wild female fox (Vulpes vulpes schrencki) and in Ixodes persulcatus ticks collected from the fox on Sapporo, Hokkaido, Japan. Spirochetes were detected in I. persulcatus, as well as skin lesions, brain, heart, kidney, and liver of the fox. Five of seven isolates reacted with a monoclonal antibody against Borrelia afzelii specific Osp B. Deoxyribonucleic acid (DNA) relatedness of a brain isolate was 89% to B. afzelii, and ranged from 50 to 67% to three other species. Immunoglobulin G antibodies to B. afzelii, B. garinii and B. burgdorferi sensulato, when tested in an enzyme-linked immunosorbent assay (ELISA), were negative in the fox. There were no antibodies against seven serovars of Leptospira interrogans.

Animals↗

PubMed1993

Effect of TYB-2285 on histamine release from human basophils in the presence/absence of IL-3.

1. The present study was carried out to investigate the effect of TYB-2285 (3,5-bis(acetoxyacetylamino)-4-chlorobenzonitrile) on histamine release from human basophils upon stimulation with anti-IgE in the presence/absence of recombinant interleukin 3 (rIL-3). 2. Histamine release was enhanced by the pretreatment of basophils with rIL-3 (0.3-10 U/ml) in 18 out of 22 subjects. 3. Histamine release in the presence of rIL-3 was inhibited by TYB-2285 and disodium cromoglycate (DSCG) in a dose-dependent manner (1-100 microM). 4. Histamine release in the absence of rIL-3 was not inhibited by TYB-2285 or DSCG at concentrations less than 1 mM. 5. From these results, it is suggested that TYB-2285 and DSCG might regulate allergic inflammation by the suppression of mediator release enhanced by IL-3.

Antibodies, Anti-Idiotypic↗

PubMed1993

Effect of TYB-2285 on antigen-induced histamine release from mouse bone marrow-derived persisting cells (P-cells) primed with interleukin-3-containing conditioned medium (IL3-CM).

1. The present study was carried out to investigate the effect of TYB-2285 [3,5-bis(acetoxyacethylamino)-4-chlorobenzonitrile] on histamine release from persisting cells (P-cells) primed with interleukin-3-containing conditioned medium (IL3-CM). 2. IL3-CM enhanced antigen-induced histamine release from P-cells, although IL3-CM did not affect spontaneous histamine release. 3. TYB-2285 inhibited antigen-induced histamine release in the presence of IL3-CM, although it did not inhibit histamine release in the absence of IL3-CM. 4. The enhancement of histamine release by IL3-CM was reproduced by recombinant IL-3 (1-100 U/ml). 5. These results demonstrate that TYB-2285 inhibits the histamine release primed with IL-3 and also suggests that TYB-2285 might regulate allergic inflammation in vivo by the suppression of mediator release primed with IL-3.

Animals↗

PubMed1993

3-Cyano-2,6-dihydroxypyridine (CNDP), a new potent inhibitor of dihydrouracil dehydrogenase.

3-Cyano-2,6-dihydroxypyridine (CNDP) was identified as a potent inhibitor (IC50 value, 4.4 nM) of dihydrouracil dehydrogenase (DHUDase) [EC 1.3.1.2], a rate-limiting enzyme in 5-fluorouracil (5-FU) degradation. The inhibitory activity of CNDP was about 2,000 times that of uracil under our assay conditions. Kinetic analyses with partially purified enzyme from rat liver revealed that the mechanism of inhibition of DHUDase by CNDP was of mixed type with an inhibition constant (Ki) of 1.51 nM. CNDP had less effect on 5-FU phosphorylation than on 5-FU degradation. The inhibitory effect of CNDP on ribosylation of 5-FU was 600 to 1,000 times less than that on DHUDase. Moreover, CNDP did not inhibit uridine kinase, thymidine kinase, or pyrimidine phosphoribosyltransferase. Coadministration of CNDP with 1-ethoxymethyl-5-fluorouracil (EM-FU) to rats with Yoshida sarcoma elevated the level of 5-FU in both the blood and the tumor and enhanced the antitumor effect of EM-FU. These findings indicated that CNDP would be a useful chemical modulator in chemotherapy with 5-FU or its prodrugs.

Alanine↗

PubMed1993

Analysis of Borrelia species associated with Lyme disease by rRNA gene restriction fragment length polymorphism.

We investigated the usefulness of rRNA gene restriction fragment length polymorphism (RFLP) for grouping of the Borrelia isolates associated with Lyme disease or from ixodid ticks. Genomic DNA was digested with a restriction enzyme, blotted and hybridized with an rrl (23S rRNA) gene probe. The sizes of the restriction bands showed a good correlation with the genotypes recently proposed, and Borrelia isolates of diverse geographic origin formed four distinct DNA groups. Group I included all of the USA isolates and some European isolates; group II contained European isolates and Asian isolates; group III comprised European and Asian isolates; group IV included Japanese isolates and an eastern Russian isolate. Groups I, II and III corresponded to Borrelia burgdorferi, B. garinii and group VS461, respectively. The RFLPs of Japanese isolates were rather divergent and some of the isolates were quite distinct from the USA and European isolates. RFLP analysis of the rRNA genes and flanking regions, using rrl gene probes as we reported here, may be useful in the taxonomic study of Borrelia.

Blotting, Southern↗

PubMed1993

Genomic analysis of Borrelia japonica sp. nov. isolated from Ixodes ovatus in Japan.

Genetic characteristics of 12 Borrelia isolates from the tick, Ixodes ovatus, I. persulcatus, and the rodent, Apodemus speciosus ainu, in Japan were compared to members of the three genospecies of Borrelia burgdorferi sensu lato; B. burgdorferi sensu stricto, B. garinii and group VS461. The methods used in this study were the quantitative microplate DNA hybridization assay and restriction fragment length polymorphism (RFLP) analyses of the flagellin structural genes and the 16S rRNA genes. The six isolates from I. persulcatus and A. speciosus ainu were identified as genospecies B. garinii using RFLP analysis of the flagellin and 16S rRNA genes. In contrast, RFLP analysis of the six isolates from I. ovatus indicated that they were different from the three reported genospecies. DNA homology studies confirmed the RFLP results. The six isolates from I. ovatus had DNA homologies ranging from 85 to 99%, whereas DNA relatedness of the I. ovatus isolate with strains belonging to the three genospecies was 50 to 64%. These results suggest that the strains isolated from I. ovatus in Japan differ from the three genospecies and should be classified as a new genospecies of B. burgdorferi sensu lato. We propose that strains isolated from I. ovatus should be classified as B. japonica sp. nov.

Animals↗

PubMed1993

Protective activity of antisera against isolates of Borrelia burgdorferi from various geographical origins.

Antisera from rabbits immunized with two Japanese strains of Borrelia burgdorferi, HP3 an isolate from Ixodes persulcatus and HO14 an isolate from I. ovatus, or the European strain P/Bi isolated from human cerebrospinal fluid (CSF) did not passively protect hamsters from challenge with the infectious strain 297, a North American isolate from patient CSF. Antisera to strains 297 and B31, a North American isolate from I. dammini, however, provided protective effect to challenge with strain 297. Immune mice sera in the presence of homologous B. burgdorferi antigen induced the production of oxygen intermediates from mouse peritoneal exudate cells. Heterologous B. burgdorferi antigen had no effect. These results suggest that antigenic properties of Japanese strains are different from those of North American and European isolates.

Animals↗

PubMed1993

Possible role of CD5+ B cells expressing CD23 in mediating the elevation of serum-soluble CD23 in patients with rheumatoid arthritis.

Since increased levels of serum soluble CD23/Fc epsilon RII (sCD23) were evidently demonstrated in patients with autoimmune diseases such as rheumatoid arthritis (RA), the possible mechanisms responsible for the elevation of serum sCD23 were investigated in RA patients. In keeping with increased serum sCD23, high proportion of CD23+ B cells was detected in the patients; this was associated with the enhanced expression of only Fc epsilon RIIa mRNA. Upon incubation at 37 degrees C, peripheral blood mononuclear cells of the patients spontaneously released high levels of sCD23 into the culture supernatant, while the CD23 expression on their B cells was considerably maintained even after the culture. Dot blot analysis further revealed that in contrast to normal subjects, RA patients showed no complete disappearance of Fc epsilon RIIa mRNA after the spontaneous culture. In addition, sCD23 release was significantly reduced in the patients by the addition of cycloheximide. It was also found that cycloheximide exerted the inhibitory influence on the spontaneous culture-mediated expression of CD23 on CD5+ but not CD5- B cells of the patients. However, the disappearance of CD23 from CD5+ as well as CD5- B cells of cord blood samples was unaffected by the agent. These results strongly suggest that CD5+ B cells of RA patients may be specifically activated by some mechanisms responsible for the persistent expression of Fc epsilon RIIa mRNA leading to the accelerated turnover of CD23 and in turn the increased release of sCD23.

Adult↗

PubMed1993

Platelet-activating-factor-induced augmentation of production of eosinophil-lineage cells in hematopoietic precursor cells obtained from human umbilical cord blood.

Platelet-activating factor (PAF)-induced augmentation of spontaneous differentiation into eosinophil-lineage cells from hematopoietic precursor cells was found among human umbilical cord blood mononuclear cells (CBMCs). This ability of PAF to augment eosinophil production was significantly (p < 0.01) inhibited by the addition of the anti-PAF agent WEB 2086. This enhancing effect of PAF was significantly (p < 0.01) diminished by the presence of antibodies to interleukin (IL)-1 alpha, -beta and IL-3, whereas antibodies to IL-5 or granulocyte-macrophage colony-stimulating factor (GM-CSF) did not diminish it. IL-1 beta, IL-3 or IL-5 gene expression was detected in cellular RNA isolated from both medium- and PAF-stimulated CBMCs using the reverse transcription polymerase chain reaction (RT-PCR) method; however, no expression of GM-CSF was detected. Moreover, 5 times as much IL-3 was detected in the PAF-stimulated CBMC culture supernatant than in that of cells treated with the medium. In the case of IL-1 beta, there was no difference between the 2 cell preparations. On the other hand, no IL-5 or GM-CSF was detected in the supernatant after stimulation with medium or PAF. Depletion of CD2+, CD16+ or CD19+ cells, but not CD14+ cells, from CBMCs resulted in a marked decrease in PAF-induced augmentation of eosinophil production. These results suggest that PAF induces the augmentation of IL-3 production in CBMCs which in turn enhances differentiation into eosinophil-lineage cells.

Azepines↗

PubMed1993

Photodynamic DNA strand breaking activities of acridine compounds.

Induction of single strand breaks in DNA was assessed by the conversion of supercoiled closed circular plasmid DNA into the open circular form. Euflavine produced single-strand breaks following irradiation but not in the control maintained in the dark. The single strand breaking activity of photoactivated euflavine was found to be dose-dependent. The effective dose conversion 50% (ED50) of the closed circular DNA to the open circular form was 0.53 microM. A comparison of 8 acridine compounds revealed that the ED50 of diaminoacridines such as euflavine, proflavine and acridine yellow or the 3,6-dimethylamino-derivative (acridine orange) was less than 1 microM while the ED50 values of the other acridines were greater than 80 microM. Euflavine was markedly inhibited by singlet oxygen scavengers such as NaN3, histidine, alpha-tocopherol or beta-carotene and partly inhibited by superoxide dismutase, mannitol or catalase. These results suggest that enflavine induces single strand breaks in DNA mainly by a type II photodynamic mechanism. Photodynamic single strand breaking activities appeared related to their mutagenic activities on yeast. This experimental system described here is useful for the quantitative assessment of the single strand breaking activities of various photosensitizers in vitro and for the determination of active oxygen species involved in those processes.

Acriflavine↗

PubMed1993

Low mitogenic activity of synthetic lipid A analog, 2,3-acyloxyacylgalactosamine-4-phosphate, in cultured murine splenocytes.

The mitogenicity of chemically synthesized lipid A analogs, 2,3-acyloxyacylglucosamine-4-phosphate (A-103) and 2,3-acyloxyacylgalactosamine-4-phosphate (A-113), was compared. Synthetic lipid A analogs of the disaccharide-type (506), the monosaccharide-type (A-103) suspended in RPMI-1640 medium supplemented with triethylamine, and Salmonella typhimurium LT-2 lipopolysaccharide (LPS) were capable of increasing the incorporation of [3H]thymidine into splenocytes of C57BL/6 mice at various doses ranging from 1.0 to 100 micrograms/ml. However, the mitogenic activity of A-113 at these doses was markedly weaker than the activity of the above materials. When the A-103 and A-113 were suspended in RPMI-1640 medium supplemented with ethanol, the mitogenic activity of A-113 also showed lower activity than that of A-103 in the splenocytes of C57BL/6 mice. These findings indicate that the mitogenic activity of synthetic lipid A of the monosaccharide-type is affected by a kind of composed sugar.

Animals↗