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Biomedical subjects

Y Yanagihara

Publications and source records attributed to Y Yanagihara.

At least 55 records · Page 3Linked to original sources
PubMed1997

Identification of rickettsiae isolated in Japan as Coxiella burnetii by 16S rRNA sequencing.

The 16S rRNA genes of Japanese Coxiella isolates obtained from various sources and geographical areas were directly sequenced by dideoxynucleotide chain termination methods in which Taq DNA polymerase was used. The levels of sequence similarity among Japanese, European, and American isolates were more than 99%, and the Japanese isolates were identified as Coxiella burnetii, C. burnetii strains isolated worldwide, including Japan, were found to be very similar.

Animals↗
PubMed1997

A case of Lyme disease diagnosed serologically.

A 57-year-old Japanese male developed erythema migrans, arthralgia, and neurological symptoms after mountain climbing in Nagano Prefecture. On ELISA, his serum reacted to Borrelia isolated from various sources. The patient's serum reacted with a 41 kilodalton protein which was reactive with monoclonal antibody H9724 specific to flagellin of Borrelia on Western blotting. He recovered after taking minocycline 200 mg daily for 2 weeks.

Antibodies, Viral↗
PubMed1997

Consensus sequence on the genes encoding the major outer surface proteins (OspA and OspB) of Borrelia garinii isolate.

Japanese Lyme borrelias classified as ribotype IV is predominant among isolates derived from clinical specimens, reservoir rodents and Ixodes persulcatus ticks, and has been characterized as Borrelia garinii. These B. garinii isolates have antigenic and genetic features apparently different from North American, European and other Asian isolates, especially in major outer surface proteins A (OspA) and B (OspB). In this study, we cloned and sequenced the genes encoding OspA and OspB from B. garinii strain FujiP2 (ribotype IV strain) isolated from I. persulcatus in Shizuoka, Japan. A sequence analysis revealed significant differences to the previously published sequences of ospA and ospB of B. burgdorferi sensu lato. The open reading frames of ospA and ospB consist of 822 and 888 nucleotides corresponding to the proteins of 273 and 295 amino acids, with molecular weights of 29,643 and 31,786 daltons, respectively. The most interesting finding is that the two osp genes share a consensus 282 bp sequence in their carboxy-terminal portions and that the ospB gene is flanked by a 282 bp-long direct repeat sequence. The deduced amino-acid (aa) sequences of OspA and OspB of strain FujiP2 showed 60.1% homology, and have overall similarities of 70.5%, 70.3% and 75.6% to OspAB proteins of B. burgdorferi sensu stricto strain B31, Borrelia afzelii strain ACA1 and Borrelia garinii strain Ip90, respectively.

Amino Acid Sequence↗
PubMed1997

Genetic diversity of Borrelia burgdorferi sensu lato isolated in far eastern Russia.

One-hundred and fifty-seven Borrelia isolated from adult ticks, Ixodes persulcatus, and wild rodents, Clethrionomys rufocanus and Apodemus peninsulae, in the far eastern part of Russia were characterized and identified by restriction fragment length polymorphism (RFLP) of the 5S-23S rRNA intergenic spacer. Some isolates showed unique RFLP patterns and were determined as Borrelia garinii on the basis of a sequence analysis of the intergenic spacer amplicon and reactivity with species-specific monoclonal antibodies (MAbs). 86.5 and 12.7% of the tick isolates, and 74.2 and 12.9% of the rodent isolates were determined as Borrelia garinii and Borrelia afzelii, respectively, but not Borrelia burgdorferi sensu stricto was detected. This finding is similar to the results obtained from Borrelia surveys of I. persulcatus and wild rodents in Hokkaido, Japan.

Animals↗
PubMed1997

Deletion in the genes encoding outer surface proteins OspA and OspB of Borrelia garinii isolated from patients in Japan.

We detected the expression of outer surface proteins OspA and OspB, and characterized the genes encoding the two Osps of eight Borrelia garinii isolates from patients in Japan. Six of the eight strains shared a common antigenic epitope in their OspA and/or OspB proteins to monoclonal antibody P3134 against OspB, and were identified to have a conserved carboxyl terminus on their ospA and ospB genes by Southern blot hybridization. One strain, JEM4, did not express OspB protein, which was due to lack of the ospB gene. Gene cloning and sequencing analysis revealed that it had only one osp open reading frame with 819 nucleotides, which was similar to the ospA gene. The deletion of the ospB gene could be explained by a homologous recombination based on the common C-terminal sequences on the ospAB operon.

Antigens, Bacterial↗
PubMed1997

Negative finding in cross-protective activity of Japanese Borrelia isolates against infection with three species of Lyme disease Borrelia in outbred mice.

Outer surface protein A (OspA) is the most promising candidate for a component vaccine against Lyme disease caused by Borrelia burgdorferi sensu lato. Active cross-protection using a whole-cell vaccine prepared from strains belonging various OspA serotypes observed in Japan and worldwide was examined. No cross-protection was obtained by heterologous OspA-serotype vaccines. Since OspA is a highly variable protein expressed by Borrelia, this suggests that immunologically different OspA serotypes need to be combined for the development of an effective vaccine in Japan.

Animals↗
PubMed1997

PCR-restriction fragment length polymorphism analysis of the ospC gene for detection of mixed culture and for epidemiological typing of Borrelia burgdorferi sensu stricto.

Restriction fragment length polymorphism (RFLP) analysis of the outer surface protein C (ospC) gene amplicon was used for rapid screening for genetic variability within Borrelia burgdorferi sensu stricto species and for detection of multiple borreliae in culture. Primers for the ospC gene amplified a fragment of about 600 bp from Borrelia cultures. After cleavage of the amplified products by MboI and DraI, eight different RFLP types were found among 13 B. burgdorferi sensu stricto strains from various sources and geographical areas, and three RFLP types were found among 10 representative isolates from skin biopsy specimens taken from patients residing on the eastern end of Long Island, New York (B. W. Berger, R. C. Johnson, C. Kodner, and L. Coleman, J. Clin. Microbiol. 30:359-361, 1992). These results suggested that the DNA organization of B. burgdorferi sensu stricto is heterogeneous not only globally but also within a localized geographical area and that the ospC-based typing approach could differentiate the B. burgdorferi sensu stricto. From the results obtained using mixed cultures of two different RFLP types of B. burgdorferi sensu stricto, contamination of at least 0.5% of different types of Borrelia cells in culture could be detected. This method could detect a multiple-B. burgdorferi sensu stricto infection in the bladders of mice experimentally infected with two different RFLP type strains. The present study showed that RFLP analysis of ospC-PCR products is a reliable method for epidemiological typing of B. burgdorferi sensu stricto and could be used for rapid detection of mixed Borrelia culture and multiple B. burgdorferi sensu stricto infections in animals, ticks, and patients.

Antigens, Bacterial↗
PubMed1997

Glycosphingolipid-binding protein of Borrelia burgdorferi sensu lato.

The binding of Borrelia burgdorferi, the causative agent of Lyme disease, to glycosphingolipids present in various types of cells was examined. B. burgdorferi bound specifically to galactosylceramide (GalCer) and glucosylceramide (GlcCer) but not to other glycosphingolipids, as determined by a thin-layer chromatography (TLC) overlay assay. The binding specificity of B. burgdorferi to various glycosphingolipids suggested that the binding receptor in this species is ceramide monohexoside. The levels of binding of B. burgdorferi virulent strain 297 to GlcCer, sulfatide, lactosylceramide, and galactosylgloboside were 56.2, 1.6, 15.9, and 9.7%, respectively, relative to that to GalCer. Virulent low-passage strains of B. burgdorferi were serially subcultured in BSK II medium, and the resultant high-passage strains were not capable of infecting mice and did not induce footpad swelling. The levels of binding of the low-passage strains to GalCer on TLC plates and to CHO-K1 cells in vitro were threefold higher than those of high-passage strains. Binding was not affected by pretreatment of Borrelia with monospecific anti-outer surface protein C (OspC) antiserum. These results indicated that the binding of Borrelia to glycosphingolipid expressed on the cell surface plays an essential role in infection of mammalian hosts. However, OspC was not associated with binding. The necessity of the sugar and N-acyl moieties in GalCer for the binding of Borrelia was shown by a TLC overlay assay using chemically modified GalCer. Furthermore, three proteins, 67-kDa protein, 62-kDa Hsp60, and 41-kDa flagellin, were involved in binding of B. burgdorferi to GalCer, as shown by blotting assay using biotinylated GalCer as a probe.

Animals↗
PubMed1997

Association of natural killer cell activity with serum IgE.

Association of natural killer (NK) cell activity (NKCA) or NK cell subsets with total IgE or antigen-specific IgE in serum were studied among 66 healthy non-allergic males. NKCA was determined by using 61Cr release assay and NK subsets were counted usings surface antigens (CD16, CD57) in peripheral blood mononuclear cells. NKCA was associated mainly with the frequency of a CD16+,CD57- subset. When the subjects were classified into three groups according to total IgE values in serum (grade 0: IgE < 10 IU/ml; grade 1: IgE 10-400 IU/ml; grade 2: IgE > 400 IU/ml), one-way analysis of variance of NKCA showed that the grades of total IgE were significantly associated with increasing NKCA. In addition, NKCA in the grade 0 group was significantly lower than that in the grade 2 group and than a mixture of grade 1 group and grade 2 group. A similar finding was not observed between NKCA and RAST for specific IgE against mites. Therefore, NKCA may be related to total IgE level in serum.

Adult↗
PubMed1997

Excitatory amino acid receptors in the paraventricular hypothalamic nucleus mediate pressor response induced by carotid body chemoreceptor stimulation in rats.

In urethane-anesthetized rats with spinal transection, antagonists of excitatory amino acid receptors, P2 purinoceptors and adrenoceptors were microinjected into the paraventricular hypothalamic nucleus (PVN) and their effects on the pressor response evoked by carotid body chemoreceptor stimulation were examined. Microinjections of the non-selective excitatory amino acid antagonist kynurenate, the non-NMDA receptor antagonist CNQX and the NMDA antagonist 2-amino-5-phosphonovalerate (AP5) into the PVN inhibited the chemoreceptor reflex-induced pressor response. The excitatory amino acid agonist L-glutamate injected into the PVN produced an increase in blood pressure. The P2 purinoceptor antagonist suramin did not affect the pressor response and ATP did not affect basal blood pressure. The alpha adrenoceptor antagonist phentolamine, prazosin and yohimbine also inhibited the chemoreceptor-induced pressor response, while the beta antagonist propranolol did not affect it. These findings indicate that excitatory amino acid receptors and alpha adrenoceptors in the PVN are involved in mediating the pressor response induced by carotid body chemoreceptor stimulation in rats.

2-Amino-5-phosphonovalerate↗
PubMed1997

[Cross-reactivity between bromelain and soluble fraction from wheat flour].

It is revealed that patients allergic to a water-soluble fraction from wheat flour were sensitive to pineapple enzyme, bromelain. Since bromelain has a high similarity to other SH-proteases such as papain, it may imply that the patients may recognize varieties of other SH-proteases as the epitope.

Bromelains↗
PubMed1996

Characterization of Borrelia sp. isolated from Ixodes tanuki, I. turdus, and I. columnae in Japan by restriction fragment length polymorphism of rrf (5S)-rrl (23S) intergenic spacer amplicons.

Borrelia isolated from various sources in Japan, including rare species of ixodid ticks, Ixodes tanuki, I. turdus, and I. columnae, were characterized by restriction fragment length polymorphism analysis and sequencing analysis of the 5S-23S rRNA intergenic spacer amplicon. Borrelia sp. isolated from I. tanuki, I. turdus and I. columnae generated restriction fragment length polymorphism patterns different from those of known B. burgdorferi sensu lato isolates previously reported. Furthermore, some B. afzelii and B. garinii isolated in Japan showed unique RFLP patterns which were not observed among European B. afzelii and B. garinii.

Animals↗
PubMed1996

Inhibition of basophil histamine release by a haptenic peptide mixture prepared by chymotryptic hydrolysis of wheat flour.

For application to the treatment of wheat-sensitive allergy, we developed a practical method for producing a haptenic peptide mixture, and evaluated its haptenic properties. Wheat flour was hydrolyzed with chymotrypsin to obtain a hydrolysate, and the diffusible fraction from the hydrolysate was subjected to gel-filtration. The resulting oligopeptide fraction could bind to wheat-specific IgE antibodies in the serum of patients allergic to wheat. Since this peptide mixture did not induce histamine release from basophils in these patients, it was concluded that the peptide mixture was composed of monovalent haptens. Histamine release from antigenstimulated basophils was almost completely inhibited when the basophils were preincubated with the haptenic peptide mixture. These results suggest that this haptenic peptide mixture can regulate the allergenic reaction in an epitope-specific manner.

Basophils↗
PubMed1996

Evidence for a role of phosphatidylinositol 3-kinase in IL-4-induced germline C epsilon transcription.

Association of interleukin-4 receptor (IL-4R) with phosphatidylinositol 3-kinase (PI3-kinase) has been demonstrated as the proximal event of IL-4 signaling. We investigated the role of this enzyme in the IL-4 signaling pathway in a human Burkitt lymphoma B cell line, DND39, that expresses germline C epsilon transcripts in response to IL-4. Stimulation of DND39 cells with IL-4 resulted in an accumulation of PI-3-monophosphate as well as a decrease of PI-4,5-bisphosphate, which were abrogated by wortmannin, a potent inhibitor of PI3-kinase. Activation of PI3-kinase was further confirmed by the finding that IL-4 caused an increase in PI3-kinase activity coimmunoprecipitated with anti-IL-4R and with anti-JAK3 kinase antibodies. As a possible downstream event of PI3-kinase activation, the translocation of a zeta isoform of protein kinase C (PKC) from the cytosol to the membrane fraction was observed after IL-4 stimulation, and wortmannin also suppressed this translocation. Moreover, IL-4-induced expression of germline C epsilon transcription was inhibited not only by wortmannin, but also by a PKC inhibitor, K252a. These results suggest that the signaling pathway involving PI3-kinase and PKC zeta plays an important role in induction of germline C epsilon transcription in DND39 cells by IL-4.

Amino Acid Sequence↗
PubMed1996

A major wheat allergen has a Gln-Gln-Gln-Pro-Pro motif identified as an IgE-binding epitope.

The minimum primary structure of the IgE-binding epitope in wheat gluten was determined as Gln-Gln-Gln-Pro-Pro. The N-terminal glutamine and the two proline residues were essential for epitopic function. The occurrence of the second glutamine residue and acetylation of the N-terminal amino group were found to exert some auxiliary functions, whereas only a lesser contribution was expected for the third glutamine residue. It has also been confirmed that acetyl-Gln-Gln-Gln-Pro-Pro bound to wheat-specific IgE antibodies in the sera of patients allergic to wheat, although it did not induce histamine release from the basophils of these patients. Taken together, we concluded that the Gln-Gln-Gln-Pro-Pro motif constituted an IgE-binding rather than immunogenic epitope and also that acetyl-Gln-Gln-Gln-Pro-Pro might act as a hapten capable of binding to specific IgE molecules. The possibility exists that this peptide will have practical application to therapy for or prevention of wheat-sensitive allergy.

Allergens↗
PubMed1996

A new assay system detecting antibody production and delayed-type hypersensitivity responses to trinitrophenyl hapten in an individual mouse.

A new assay system detecting antibody production and delayed-type hypersensitivity (DTH) responses to trinitrophenyl hapten in an individual mouse (AS-DAD) was established. BALB/c mice were immunized intraperitoneally with varying amounts of 2,4,6-trinitrophenylated sheep red blood cells (TNP-SRBC) on day 0. Venous blood was collected on days 2, 4, 6, 8 and 10. Levels of anti-TNP IgM and IgG serum were assayed by enzyme-linked immunosorbent assay (ELISA). After series of bleeding the mice were challenged with 2,4,6-trinitrobenzene sulfonic acid (TNBS) solution in the footpad on day 14. Footpad swelling was measured 24 or 48 h after the challenge. Peak responses of the anti-TNP IgM and IgG production were detected 4 or 6 days after the immunization with 10(9) TNP-SRBC. Maximum DTH response was also observed with 10(9) TNP-SRBC 24 h after the challenge on day 14. The antibody and DTH responses were also induced in other normal inbred strains such as C3H/He and DBA/1 but not BALB/c nu/nu mice. To evaluate AS-DAD in immunopharmacological studies, various immunomodulating agents were examined in BALB/c mice by subcutaneous administration on days 0, 1, 2 and 3. Cyclosporin or cyclophosphamide at 100 mg/kg/day completely inhibited not only the anti-TNP IgM and IgG production but also the TNP-specific DTH response. Prednisolone at 0.5 mg/kg/day had no significant effect on the IgM and IgG production, whereas it inhibited the TNP-specific DTH response. Interestingly, histamine-added mouse gamma-globulin at 150 MG/kg/day clearly enhanced the anti-TNP IgM and IgG production, while it showed a suppressive effect on the TNP-specific DTH response. Levamisole at 5.0 mg/KG/day showed suppressive effects on the anti-TNP IgG production without affecting the IgM production and the DTH response. These results suggest that AS-DAD is useful for evaluating the immunopharmacological action of various agents.

Animals↗