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Y Hidaka

Publications and source records attributed to Y Hidaka.

At least 73 records · Page 4Linked to original sources
PubMed1998

[Stress, endocrine, and immune system; stress induces the onset of autoimmune diseases].

Stress can affect endocrine and immune function. In this paper, we reviewed the interaction between stress and Graves disease, which is induced by thyroid-stimulating autoantibodies. Psychological stress was reported to be a risk factor for Graves' disease, although the mechanism by which stress induces autoimmune disease remains unknown. Moreover, we found that other stress, such as delivery and allergic rhinitis can induce the onset of Graves' disease. Immune rebound after delivery and the overproduction of Th 2 (type 2 helper T cells)-derived cytokines after an attack of allergic rhinitis might help produce thyroid-stimulating autoantibodies.

Autoimmune Diseases↗
PubMed1997

Demonstration of dimer formation of the cytoplasmic domain of a transmembrane osmosensor protein, EnvZ, of Escherichia coli using Ni-histidine tag affinity chromatography.

EnvZ is a transmembrane osmosensor which regulates the phosphorylation of OmpR, a transcription factor for ompF and ompC genes which encode the major outer membrane porin proteins, OmpF and OmpC in Escherichia coli. Autophosphorylation of EnvZ occurs through a transphosphorylation reaction between two EnvZ molecules. To elucidate the molecular mechanism of signal transduction by EnvZ, we examined the dimer formation of the EnvZ cytoplasmic domain [EnvZ(C)]. For this purpose, we developed a method to determine the complex formation between the purified EnvZ(C) and the purified His6-EnvZ(C) by means of Ni-6xhistidine tag affinity chromatography. When the mixture of EnvZ(C) and His6-EnvZ(C) was applied to Ni-NTA resin, both His6-EnvZ(C) and EnvZ(C) were bound to the resin, indicating that EnvZ can form an oligomer without the periplasmic and transmembrane domains. Binding experiments using the Ni-NTA resin revealed that EnvZ(C) forms a dimer with the Ka value for dimerization being approximately 10(5) M(-1) in the equilibrium state.

Bacterial Outer Membrane Proteins↗
PubMed1997

Effects of autoantibodies on the course of pregnancy and fetal growth.

OBJECTIVE: To assess the effects of autoantibodies on the course of pregnancy and fetal growth. METHODS: One thousand one hundred seventy-nine healthy women with singleton gestations were screened in early pregnancy for seven kinds of autoantibodies: antithyroid microsomal antibody, antithyroglobulin antibody, two kinds of rheumatoid factor, antinuclear antibody, anti-DNA antibody, and antimitochondrial antibody. RESULTS: In 228 cases (19.3%), at least one autoantibody was found; however, overlap of autoantibodies in the same individual was unexpectedly rare, and only two cases were positive for as many as four autoantibodies. A significantly higher rate of spontaneous abortion was observed in antibody-positive subjects, especially those with antithyroid microsomal (10.4%) or antinuclear antibodies (16.0%), compared with all antibody-negative subjects (5.5%). There were no significant differences in any outcome assessed among subjects positive for antithyroglobulin antibody, anti-DNA antibody, or antimitochondrial antibody compared with all antibody-negative subjects. None of the seven autoantibodies affected the rates of preterm delivery, stillbirth, pregnancy-induced hypertension, malformation, or gender ratio. CONCLUSION: Antithyroid microsomal antibody and antinuclear antibody are the only autoantibodies that increase the abortion rate.

Adult↗
PubMed1997

Twenty-three-year follow-up study of rubella antibodies after immunization in a closed population, and serological response to revaccination.

Twenty-six institutionalized children immunized with a Japanese rubella vaccine, Matsuba strain, have been observed for 23 years and the persistence of vaccine-induced rubella immunity documented. All vaccinees were shown to have seroconverted to rubella virus in a haemagglutination inhibition (HI) test, and the geometric mean titre (GMT) of rubella HI antibody rose to 2 5-8 months after vaccination (Ueda et al., Acta Paediatrica Japonica, Overseas Edition 1978, 20, 8-14). The GMT then declined gradually to 2 23 years after inoculation, except in four cases (15.4%) which had reverted to negative. However, three of the four maintained a rubella HI antibody titre of 1:4. Twelve of the 26 vaccinees were revaccinated 24 years after primary vaccination, and all ten cases having initial titres of < or = 1:16 demonstrated secondary responses. Rubella immunity induced by vaccination had persisted, so routine booster immunization did not seem necessary. However, a second immunization programme should be considered to achieve high antibody-positive rates and to protect against primary vaccine failure.

Adolescent↗
PubMed1997

Breast milk is not a significant source for early Epstein-Barr virus or human herpesvirus 6 infection in infants: a seroepidemiologic study in 2 endemic areas of human T-cell lymphotropic virus type I in Japan.

In order to evaluate the possibility of Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6) transmission via breast milk, a total of 331 serum specimens collected from bottle-fed and breast-fed children and their mothers, in 2 endemic areas of human T-cell lymphotropic virus type I (HTLV-I) in Japan, were assayed for antibodies to EBV and HHV-6. The seroprevalences of EBV and HHV-6 were over 95% both in the mothers of bottle-fed children and in those of breast-fed children. The seroprevalence of EBV at 12-23 months of age was 54.5% (36/66) and 55.8% (24/43) in breast-fed children and bottle-fed children, respectively. The seroprevalence of HHV-6 at 12-23 months of age was 90.9% (60/66) and 93.0% (40/43) in breast-fed children and bottle-fed children, respectively. No difference was observed between the seroprevalences of EBV and HHV-6 in breast-fed and bottle-fed children at 12-23 months of age. Our seroepidemiologic data indicate that breast milk is not a significant source of early EBV or HHV-6 infection in infancy.

Antibodies, Viral↗
PubMed1997

Pathogenicity of glycoprotein C-deficient herpes simplex virus 1 strain TN-1 which encodes truncated glycoprotein C.

A clinical isolate of herpes simplex virus 1 (TN-1) from a stromal keratitis patient was found to be defective in the glycoprotein C (gC) gene (UL44), thus resulting in the production of truncated gC upon infection. To study the pathogenetic role of truncated gC, we prepared a recombinant LTN-8 derived from TN-1 with deletions of the 1.5 kilobase pairs of the gC gene including the initiation codon. A penetration assay revealed LTN-8 to be less efficient in its penetration ability than TN-1, the laboratory strain KOS and RTN-1-20-3, a recombinant derived from TN-1 with the KOS gC gene. The penetration of LTN-8 was facilitated by the addition of TN-1-infected culture medium. TN-1 virus preparations had no hemagglutinating activity. However, the animals infected with TN-1 did develop hemagglutination inhibition (HI) antibodies. The LTN-8-infected animals did not develop HI antibodies. The pathogenicity in BALB/c mice following either corneal, intraperitoneal or intracerebral inoculation did not significantly differ among TN-1, RTN-1-20-3 or LTN-8. Our results indicate that truncated gC was sufficient for the induction of HI antibodies and was also able to facilitate penetration in vitro. Although truncated gC might be a virulence factor acting as a decoy, both truncated gC and intact gC had little effect on the outcome following intracerebral, intraperitoneal or corneal inoculation.

Animals↗
PubMed1997

Changes in T, B, and NK lymphocyte subsets during and after normal pregnancy.

PROBLEM: Pregnancy affects the maternal immune system and the clinical course of maternal diseases. Here we report the changes in the detailed lymphocyte subsets of helper T cells, suppressor T cells, CD5+ B cells, T cell receptor (TCR) alpha beta-positive T cells (T alpha beta cells), TCR alpha beta-negative T cell (T gamma delta cells), and other during and after pregnancy through to one year postpartum, and discuss the significance of the changes. METHOD: The absolute numbers of helper T cells, suppressor T cells, cytotoxic T cells, TCR alpha beta-negative T cells (T gamma delta cells), CD5- B cells, CD5+ B cells, and NK cell subsets were examined by two-color flow cytometry in peripheral blood from 51 healthy non-pregnant women, 106 healthy pregnant women, and 148 healthy postpartum women. RESULTS: In early pregnancy, the numbers of suppressor T cells and NK cells with strong cytotoxicity (NK+3 cells) increased, and the number of cytotoxic T cells decreased. In late pregnancy, the helper T cell and NK+3 cell numbers decreased. T alpha beta, CD5- B and CD5+ B cells decreased during pregnancy. After delivery, helper T cells and cytotoxic T cells increased from 1 to 4 months postpartum, and suppressor T cells increased at 7 months postpartum. TCR alpha beta-negative T cells increased at 4 to 10 months postpartum. Both CD5- and CD5+ B cells decreased further at 1 month postpartum, but CD5+ B cells increased markedly at 7 to 10 months postpartum. CONCLUSIONS: These data indicate that 1) early increases of suppressor T cells and NK+3 cells during pregnancy may be related to the mechanism to accept or reject the fetus in early pregnancy, respectively; 2) late decreases of helper T cells and NK+3 cells may be related to the maintenance of pregnancy: 3) postpartum increases of helper T cells, cytotoxic T cells, TCR alpha beta-negative T cells (T gamma delta cells), and CD5+ B cells may be related to the postpartum aggravation of autoimmune diseases; and 4) the immunological effects of pregnancy remains until about 1 year after delivery.

Adult↗
PubMed1997

Nitrite reductase from Pseudomonas aeruginosa induces inflammatory cytokines in cultured respiratory cells.

Persistent infection with Pseudomonas aeruginosa increases interleukin-8 (IL-8) levels and causes dense neutrophil infiltrations in the airway of patients with chronic airway diseases. To investigate the role of P. aeruginosa infection in IL-8 production in the airway of these patients, we examined whether cell lysates of P. aeruginosa could cause IL-8 production from human bronchial epithelial cells. Diluted sonicated supernatants of P. aeruginosa (SSPA) with a mucoid or nonmucoid phenotype stimulated human bronchial epithelial (BET-1A) cells to produce IL-8. In this study, we have purified a 59-kDa heat-stable protein with IL-8-inducing activity from the SSPA by sequential ion-exchange chromatography. The N-terminal sequence of this purified protein completely matched a sequence at the N-terminal part of the mature protein of nitrite reductase from P. aeruginosa. In addition, immunoblotting with a polyclonal immunoglobulin G (IgG) against recombinant Pseudomonas nitrite reductase demonstrated a specific binding to the purified protein. Furthermore, the immunoprecipitates of the SSPA with a polyclonal IgG against recombinant nitrite reductase induced a twofold-higher IL-8 production in the BET-1A cell culture than did the immunoprecipitates of the SSPA with a control IgG. These lines of evidence confirmed that Pseudomonas nitrite reductase was responsible for IL-8 production in the BET-1A cells. The purified nitrite reductase induced maximal expression of IL-8 mRNA in the BET-1A cells at 1 to 3 h after stimulation, and the IL-8 mRNA expression declined by 8 h after stimulation. New protein translation was not required for nitrite reductase-mediated IL-8 mRNA expression in the BET-1A cells. Nitrite reductase stimulated the BET-1A cells, as well as human alveolar macrophages, pulmonary fibroblasts, and neutrophils, to produce IL-8. In contrast, nitrite reductase induced significant levels of tumor necrosis factor alpha and IL-1beta protein only in human alveolar macrophages. These data support the notion that nitrite reductase from P. aeruginosa induces the production of inflammatory cytokines by respiratory cells and may contribute to the pathogenesis of chronic airway diseases and persistent P. aeruginosa infection.

Bronchi↗
PubMed1997

Characterization of a thermostable DNA photolyase from an extremely thermophilic bacterium, Thermus thermophilus HB27.

The photolyase gene from Thermus thermophilus was cloned and sequenced. The characteristic absorption and fluorescence spectra of the purified T. thermophilus photolyase suggested that the protein has flavin adenine dinucleotide as a chromophore. The second chromophore binding site was not conserved in T. thermophilus photolyase. The purified enzyme showed light-dependent photoreactivation activity in vitro at 35 and 65 degrees C and was stable when subjected to heat and acidic pH.

Amino Acid Sequence↗
PubMed1997

Thyrotropin-receptor and thyroid peroxidase-specific T cell clones and their cytokine profile in autoimmune thyroid disease.

We studied the cytokine profile and the immune responses to thyroid antigens of specific T cell clones (TCC) isolated from patients with Hashimoto's thyroiditis (HT) and Graves' disease (GD). Antigen-specific TCC were reactive to thyroid peroxidase (TPO), thyroglobulin (Tg) or human recombinant TSH-receptor extracellular domain (TSH-R), and/or their respective peptides. Of the 43 clones derived from HT patients, 65% were reactive to TPO, and 59% of the 32 clones derived from GD patients were reactive to TSH-R. TPO epitopes 100-119 and 625-644 were recognized by 75% of HT-derived clones, whereas TSH-R epitopes 158-176, 207-222, and 343-362/357-376 were recognized by 85% of GD-derived TCC. The TCC were classified according to their cytokine profile into T helper cell (Th)0 [secreting interleukin (IL)-4, IL-5, interferon (IFN)-gamma], Th1 (secreting IFN-gamma) and Th2 (secreting IL-4 and/or IL-5). Tumor necrosis factor-beta and IL-10 were produced by all subsets. The specific TCC were predominantly Th1-like cells in HT, and were Th0- and Th1-like cells in GD. Fifty three percent of Th0 clones were derived from GD patients and were reactive to TSH-R, whereas 50% of Th1 clones were derived from HT patients and were reactive to TPO or Tg. Most Th2 clones (82%) were reactive to TPO and were established from peripheral blood. All these clones produced IL-5, and 64% produced IL-4 and IL-10. Interestingly, IFN-gamma was highly produced by TPO- or Tg-specific clones established from HT thyroid tissue. These results confirm at the clonal level our previous studies regarding T cell epitopes on TPO and TSH-R molecules and support the concept that immunodominant T cell epitopes are located on amino acid residues 100-119 and 625-644 of TPO in HT and amino acid residues 158-176, 207-222 and 343-362/357-376 of TSH-R in GD. Our studies also demonstrate that thyroid-specific T cells can be classified into Th0, Th1, and Th2 subsets. TPO- or Tg-specific clones with Th1 phenotype appear to be involved in the pathogenesis of HT, mediating thyroid tissue destruction, whereas TSH-R clones with Th0 phenotype may induce thyroid-stimulating autoantibodies in GD.

Autoantigens↗
PubMed1997

Increased serum concentration of soluble CD30 in patients with Graves' disease and Hashimoto's thyroiditis.

This study investigated serum levels of the soluble form of CD30 (sCD30), which is mainly secreted from T helper 2(Th2) cells, in autoimmune thyroid diseases. The possible relationship of sCD30 to autoantibody production was also evaluated. Serum levels of sCD30 were determined by an enzyme-linked immunosorbent assay in 71 patients with Graves' disease, 37 patients with Hashimoto's thyroiditis, and 21 normal donors. Compared with normal subjects (7.1 +/- 4.5 U/mL), sCD30 was increased in patients with Graves' disease (29.2 +/- 25.2 U/mL, P < 0.0001) and in patients with Hashimoto's thyroiditis (29.9 +/- 26.9 U/mL, P < 0.0001). In Graves' disease, sCD30 levels were higher in thyrotoxic patients (41.7 +/- 31.2 U/mL, P < 0.001) than in remission patients (15.8 +/- 11.0 U/mL), and a significant correlation was observed between sCD30 levels and serum activities of TSH receptor antibody (r = 0.444, P < 0.0001). In Hashimoto's thyroiditis, sCD30 levels were higher in patients with transient destructive thyrotoxicosis caused by the aggravation of the disease (48.8 +/- 34.4 U/mL, P < 0.05) than in euthyroid patients (24.2 +/- 19.4 U/mL). These data suggest that serum sCD30 is a valuable marker of disease activity and support an important role of the Th2-type immune response in the pathogenesis in Graves' disease and Hashimoto's thyroiditis.

Adult↗
PubMed1997

Five cases of measles secondary vaccine failure with confirmed seroconversion after live measles vaccination.

We report 5 patients with secondary vaccine failure (SVF) who were infected with natural measles 2, 5, 5, 7 and 12 years, respectively, after vaccination with further attenuated live measles vaccine during infancy. Their seroconversion had been confirmed after vaccination. Three of the 5 patients had mild (modified) measles, while the remaining 2 patients had typical measles. The hemagglutination inhibition antibody titers to measles virus in paired acute and convalescent sera showed a secondary response pattern in 4/5 patients, and a primary response pattern was present in the remaining patient. Measles IgM antibodies were present in all patients during the convalescent stage. The patient with the primary response pattern may have had a decrease in the B cell memory during the 5-year period between vaccination and infection. This may be the first SVF case report that confirms the existence of completely waning immunity in recipients of the further attenuated live measles vaccines.

Adolescent↗
PubMed1997

[Laboratory diagnosis before onset and prediction of Graves' disease].

Graves' thyrotoxicosis frequently occurs after delivery through immune rebound mechanism. We tried to establish a systematic method of predicting postpartum onset of Graves' thyrotoxicosis. We followed pregnant women with anti-thyroid microsomal antibody (MCAb) from their early pregnancy to the postpartum period, and analyzed the relation between activities of thyroid stimulating antibodies (TSAb) in early pregnancy and the postpartum occurrence of Graves' disease. Among 71 subjects with positive MCAb, 7 showed positive TSAb in their early pregnancy without any thyroid dysfunction. All 7 developed thyroid dysfunction in postpartum period. Five of seven (70% of TSAb positive subjects) developed Graves' disease. None of 64 TSAb-negative subjects developed Graves' thyrotoxicosis, though 44 developed various types of thyroid dysfunction due to postpartum autoimmune thyroiditis. Graves' thyrotoxicosis also occurs after an attack of allergic rhinitis. A patient who developed Graves' thyrotoxicosis after an attack of allergic rhinitis showed positive TSAb before the attack of allergic rhinitis. These findings suggest that high risk of Graves' thyrotoxicosis onset can be predicted by the detection of TSAb.

Female↗
PubMed1996

The significance of Ser1029 of the heat-stable enterotoxin receptor (STaR): relation of STa-mediated guanylyl cyclase activation and signaling by phorbol myristate acetate.

To characterize Ser1029 in STaR at a consensus sequence of phosphorylation site by PKC, two mutants of mS1029A with replacement of Ser1029 to Ala1029 and C delta 1029 lacking 22 amino acids including Ser1029 were prepared. Preincubation of the wild type-STaR (wt-STaR) transfectant with 1 microM PMA caused additional STa-mediated guanylyl cyclase (GC) activation compared to control, whereas the mS1029A- and C delta 1029-transfected cells did not show a similar enhanced GC activation by PMA. After metabolic labeling with [32P]phosphate, transfected cells with wt-STaR and mutants were incubated with 1 microM PMA. Subsequent 32P-radiolabeled proteins were immunoprecipitated using anti-STaR antibody, and analyzed by autoradiography after separation on SDS-PAGE. The immunoprecipitated wt-STaR but not mS1029A and C delta 1029 had a significant radioactivity. These results suggest that the effect of PMA on wt-STaR transfectants may be caused by phosphorylation of Ser1029. The C delta 1012 mutant, with further truncation (Gln1012-Phe1050) of the carboxy terminus, did not show STa-mediated GC activation. Based on these data, these 17 amino acids (Gln1012-Ala1028), essential for signaling of GC activation by STa, have an abundance of basic amino acids which might be functionally influenced by phosphorylation of Ser1029.

Amino Acid Sequence↗