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Nobuyuki Miyasaka

Publications and source records attributed to Nobuyuki Miyasaka.

At least 19 recordsLinked to original sources
PubMed2006

Direct modulation of rheumatoid inflammatory mediator expression in retinoblastoma protein-dependent and -independent pathways by cyclin-dependent kinase 4/6.

OBJECTIVE: It is known that the cyclin-dependent kinase inhibitor (CDKI) gene p21(Cip1) suppresses rheumatoid inflammation by down-modulating type I interleukin-1 receptor (IL-1RI) expression and inhibiting JNK activity. The purpose of this study was to determine whether CDK activity directly modulates the production of inflammatory molecules in patients with rheumatoid arthritis (RA). METHODS: Genes for the CDKIs p16(INK4a) and p18(INK4c), a constitutively active form of retinoblastoma (RB) gene product, cyclin D1, and CDK-4, were transferred into RA synovial fibroblasts (RASFs). RASFs were also treated with a synthetic CDK-4/6 inhibitor (CDK4I). Levels of matrix metalloproteinase 3 (MMP-3), monocyte chemoattractant protein 1 (MCP-1), and IL-1RI expression were determined by Northern blotting, real-time polymerase chain reaction analysis, and enzyme-linked immunosorbent assay. CDKIs were immunoprecipitated to reveal their association with JNK. RESULTS: Transfer of the p16(INK4a) and p18(INK4c) genes and CDK4I suppressed the production of MMP-3 and MCP-1. Unlike p21(Cip1), neither CDKI gene inhibited IL-1RI or JNK. The expression of MMP-3 was up-regulated when CDK-4 activity was augmented. This regulation functioned at the messenger RNA (mRNA) level in MMP-3, but not in MCP-1. Transfer of active RB suppressed the production of MMP-3 and MCP-1 without changing their mRNA levels. CONCLUSION: CDK-4/6 modulated the production of MMP-3 and MCP-1. MMP-3 production was regulated primarily at the mRNA level in an RB-independent manner, whereas MCP-1 production was controlled posttranscriptionally by RB. These results show that cell cycle proteins are associated with control of mediators of inflammation through multiple pathways.

Arthritis, Rheumatoid↗
PubMed2006

Guidelines for the proper use of etanercept in Japan.

Application of biological agents targeting inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) dramatically caused a paradigm shift in the treatment of rheumatoid arthritis (RA). Infliximab, a chimeric anti-TNF-alpha monoclonal antibody, has initially been introduced to Japan in 2003 and shown to be dramatically effective in alleviating arthritis refractory to conventional treatment. However, serious adverse events such as bacterial pneumonia, tuberculosis, and Pneumocystis jiroveci pneumonia were reported to be in relatively high incidence; i.e., 2%, 0.3%, and 0.4%, respectively, in a strict postmarketing surveillance of an initial 4000 cases in Japan. Etancercept, a recombinant chimeric protein consisting of p75 TNF-alpha receptor and human IgG, was subsequently introduced to Japan in March of 2005. We therefore drew up treatment guidelines for the use of etanercept to avoid potential serous adverse events, since only approximately 150 cases have been included in the clinical study of etanercept in Japan. The guidelines were initially designed by the principal investigators (N.M, T.T., K.E.) of rheumatoid arthritis study groups of the Ministry of Health, Labor and Welfare (MHLW), Japan, and finally approved by the board of directors of the Japan College of Rheumatology. The MHLW assigned a duty to the pharmaceutical companies to perform a complete postmarketing surveillance of an initial 3000 cases to explore any adverse events, and this was performed according to the treatment guidelines shown in this article.

Antirheumatic Agents↗
PubMed2006

Leflunomide-related acute interstitial pneumonia in two patients with rheumatoid arthritis: autopsy findings with a mosaic pattern of acute and organizing diffuse alveolar damage.

We describe two cases of leflunomide-related interstitial pneumonia (IP). A 75-year-old woman with rheumatoid arthritis (RA) developed rapidly progressing IP 45 days after institution of leflunomide. She died of respiratory failure, and an autopsy revealed a mixed pattern of acute and organizing diffuse alveolar damage. A 69-year-old woman with RA also developed acute IP 3 months after institution of leflunomide. Methylprednisolone pulse therapy and cholestyramine ameliorated her IP. The implication of leflunomide in the pathogenesis of IP was suggested.

Aged↗
PubMed2006

Identification of a human peripheral blood monocyte subset that differentiates into osteoclasts.

Increased bone resorption mediated by osteoclasts causes various diseases such as osteoporosis and bone erosion in rheumatoid arthritis (RA). Osteoclasts are derived from the monocyte/macrophage lineage, but the precise origin remains unclear. In the present study, we show that the purified CD16- human peripheral blood monocyte subset, but not the CD16+ monocyte subset, differentiates into osteoclast by stimulation with receptor activator of NF-kappaB ligand (RANKL) in combination with macrophage colony-stimulating factor (M-CSF). Integrin-beta3 mRNA and the integrin-alpha(v)beta3 heterodimer were only expressed on CD16- monocytes, when they were stimulated with RANKL + M-CSF. Downregulation of beta3-subunit expression by small interfering RNA targeting beta3 abrogated osteoclastogenesis from the CD16- monocyte subset. In contrast, the CD16+ monocyte subset expressed larger amounts of tumor necrosis factor alpha and IL-6 than the CD16- subset, which was further enhanced by RANKL stimulation. Examination of RA synovial tissue showed accumulation of both CD16+ and CD16- macrophages. Our results suggest that peripheral blood monocytes consist of two functionally heterogeneous subsets with distinct responses to RANKL. Osteoclasts seem to originate from CD16- monocytes, and integrin beta3 is necessary for osteoclastogenesis. Blockade of accumulation and activation of CD16- monocytes could therefore be a beneficial approach as an anti-bone resorptive therapy, especially for RA.

Adaptor Proteins, Signal Transducing↗
PubMed2006

A multicenter, double-blind, randomized, placebo controlled trial of infliximab combined with low dose methotrexate in Japanese patients with rheumatoid arthritis.

OBJECTIVE: A placebo controlled, double-blind trial (DBT) was conducted for Japanese patients with active rheumatoid arthritis (RA) despite treatment with low dose methotrexate (MTX) to evaluate the efficacy and safety of infliximab. Extended treatment with infliximab was conducted in an open-label trial (OLT). METHODS: In the DBT, 147 patients were randomly assigned and treated with a placebo or 3 mg/kg or 10 mg/kg infliximab at Weeks 0, 2 and 6, combined with MTX. In the OLT, 129 patients from the DBT received 3 mg/kg infliximab every 8 weeks. RESULTS: The mean dose of MTX was 7.2 +/- 2.0 mg/week. Significantly more patients receiving 3 mg/kg (61.2%) and 10 mg/kg (52.9%)infliximab achieved a 20% improvement according to the American College of Rheumatology (ACR) criteria at Week 14, compared to placebo (23.4%) (p < 0.001). There was no significant difference in incidence of adverse events among the treatment groups. In patients receiving infliximab in the DBT, 11.6% of patients with serum infliximab just before the OLT developed antibodies to infliximab (ATI) in the OLT, whereas 62.2% of patients without serum infliximab did. In patients receiving placebo in the DBT, 43.9% developed ATI. CONCLUSION: The efficacy and safety of infliximab combined with low dose MTX were similar to those of the ATTRACT study. The data from the DBT and OLT also supported the importance of an induction treatment of infliximab, followed by a maintenance treatment without a long interval, giving stable serum concentrations in order to prevent formation of ATI.

Antibodies, Monoclonal↗
PubMed2005

Inhibition of CX3CL1 (fractalkine) improves experimental autoimmune myositis in SJL/J mice.

Idiopathic inflammatory myopathy is a chronic inflammatory muscle disease characterized by mononuclear cell infiltration in the skeletal muscle. The infiltrated inflammatory cells express various cytokines and cytotoxic molecules. Chemokines are thought to contribute to the inflammatory cell migration into the muscle. We induced experimental autoimmune myositis (EAM) in SJL/J mice by immunization with rabbit myosin and CFA. In the affected muscles of EAM mice, CX3CL1 (fractalkine) was expressed on the infiltrated mononuclear cells and endothelial cells, and its corresponding receptor, CX3CR1, was expressed on the infiltrated CD4 and CD8 T cells and macrophages. Treatment of EAM mice with anti-CX3CL1 mAb significantly reduced the histopathological myositis score, the number of necrotic muscle fibers, and infiltration of CD4 and CD8 T cells and macrophages. Furthermore, treatment with anti-CX3CL1 mAb down-regulated the mRNA expression of TNF-alpha, IFN-gamma, and perforin in the muscles. Our results suggest that CX3CL1-CX3CR1 interaction plays an important role in inflammatory cell migration into the muscle tissue of EAM mice. The results also point to the potential therapeutic usefulness of CX3CL1 inhibition and/or blockade of CX3CL1-CX3CR1 interaction in idiopathic inflammatory myopathy.

Animals↗
PubMed2005

Effect of a small molecule inhibitor of nuclear factor-kappaB nuclear translocation in a murine model of arthritis and cultured human synovial cells.

A small cell-permeable compound, dehydroxymethylepoxyquinomicin (DHMEQ), does not inhibit phosphorylation and degradation of IkappaB (inhibitor of nuclear factor-kappaB [NF-kappaB]) but selectively inhibits nuclear translocation of activated NF-kappaB. This study aimed to demonstrate the antiarthritic effect of this novel inhibitor of the NF-kappaB pathway in vivo in a murine arthritis model and in vitro in human synovial cells. Collagen-induced arthritis was induced in mice, and after onset of arthritis the mice were treated with DHMEQ (5 mg/kg body weight per day). Using fibroblast-like synoviocyte (FLS) cell lines established from patients with rheumatoid arthritis (RA), NF-kappaB activity was examined by electrophoretic mobility shift assays. The expression of molecules involved in RA pathogenesis was determined by RT-PCR, ELISA, and flow cytometry. The proliferative activity of the cells was estimated with tritiated thymidine incorporation. After 14 days of treatment with DHMEQ, mice with collagen-induced arthritis exhibited decreased severity of arthritis, based on the degree of paw swelling, the number of swollen joints, and radiographic and histopathologic scores, compared with the control mice treated with vehicle alone. In RA FLS stimulated with tumor necrosis factor-alpha, activities of NF-kappaB components p65 and p50 were inhibited by DHMEQ, leading to suppressed expression of the key inflammatory cytokine IL-6, CC chemokine ligand-2 and -5, matrix metalloproteinase-3, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1. The proliferative activity of the cells was also suppressed. This is the first demonstration of an inhibitor of NF-kappaB nuclear translocation exhibiting a therapeutic effect on established murine arthritis, and suppression of inflammatory mediators in FLS was thought to be among the mechanisms underlying such an effect.

Animals↗
PubMed2005

Pathogenic role of the CXCL16-CXCR6 pathway in rheumatoid arthritis.

OBJECTIVE: Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with massive T cell infiltration into the synovium. The accumulated T cells express type 1 cytokines, such as interferon-gamma (IFNgamma) and tumor necrosis factor alpha, and activated markers of inflammation, such as CD154 and inducible costimulator (ICOS). It is thought that chemokines contribute to T cell accumulation in the synovium. In this study, we examined the role of CXCL16 and CXCR6 in T cell migration and stimulation in RA synovium. METHODS: Expression of CXCL16 and CXCR6 was analyzed by immunohistochemistry, reverse transcription-polymerase chain reaction, Western blotting, and/or flow cytometry. Migration activity was assessed using a chemotaxis chamber. IFNgamma production was analyzed by enzyme-linked immunosorbent assay. The effect of anti-CXCL16 monoclonal antibody on murine collagen-induced arthritis (CIA) was evaluated. RESULTS: CXCL16 was expressed in RA synovium. CXCR6 was expressed more frequently on synovial T cells than in peripheral blood. Moreover, CXCR6-positive synovial T cells more frequently expressed CD154 and ICOS than did CXCR6-negative T cells. Stimulation with interleukin-15 (IL-15) up-regulated the expression of CXCR6 on peripheral blood T cells, and then stimulation with CXCL16 induced migration of IL-15-stimulated T cells and enhanced IFNgamma production. Furthermore, anti-CXCL16 monoclonal antibody significantly reduced the clinical arthritis score and reduced infiltration of inflammatory cells and bone destruction in the synovium of mice with CIA. CONCLUSION: Our results indicate that CXCL16 plays an important role in T cell accumulation and stimulation in RA synovium and suggest that CXCL16 could be a target molecule in new therapies for RA.

Aged↗
PubMed2005

Prediction of and prophylaxis against Pneumocystis pneumonia in patients with connective tissue diseases undergoing medium- or high-dose corticosteroid therapy.

We performed a retrospective analysis to establish a statistical model for the prediction of Pneumocystis pneumonia (PCP) in patients with connective tissue diseases (CTD) undergoing medium- or high-dose corticosteroid therapy, to identify independent risk factors for PCP and to evaluate the efficacy of the prophylactic use of trimethoprim-sulfamethoxazole (TMP/SMX) against PCP. One hundred and twenty-four patients who were receiving the equivalent of or more than 30 mg/day of prednisol-one (PSL) were classified into two groups according to the presence (prophylaxis group, n = 46) or absence (nonprophylaxis group, n = 78) of prophylactic TMP/SMX. We developed a statistical model that was suitable for predicting the development of PCP using a logistic regression analysis. The initial steroid dosage, decreased peripheral blood lymphocyte counts at 2 weeks (<500/microl), and usage of immunosuppressant during 2 weeks after the institution of PSL (>or=30 mg/day) were found to independently contribute to the development of PCP. Finally, in the patient group with a defined risk for PCP, a significant prophylactic effect of TMP/SMX was demonstrated. We recommend the prophylactic use of TMP/SMX for patients with CTD undergoing medium- or high-dose corticosteroid therapy who are determined to have a high risk of developing PCP.

Journal Article↗
PubMed2005

Proposed [corrected] Japanese guidelines for the use of infliximab for rheumatoid arthritis.

Differences in ethnic backgrounds as well as in medical and socioeconomic status often affect both the efficacy and adverse effects of medications. Recent data suggest an increased risk of opportunistic infections, especially tuberculosis (TB), among rheumatoid arthritis (RA) patients receiving infliximab, a chimeric monoclonal anti-tumor necrosis factor alpha (TNF-alpha) antibody. In this regard, the annual incidence of TB is approximately five times higher in Japan than in the United States. Furthermore, since Bacillus Calmette-Guérin vaccination is mandatory in childhood when the skin test for purified protein derivative (PPD) is negative, a high incidence of false-positive PPD skin tests is observed among the Japanese population. In addition, the upper limit of methotrexate dosage to be used for RA is lower in Japan. We have therefore established official guidelines for the proper use of infliximab in Japanese RA patients. In this review, an algorithm for the diagnosis and management of TB in RA is presented in an evidenced-based form.

Journal Article↗
PubMed2005

Polymyositis/dermatomyositis and interstitial lung disease: a new therapeutic approach with T-cell-specific immunosuppressants.

Interstitial lung disease (ILD) is a common complication of polymyositis (PM) and dermatomyositis (DM), and accounts for a significant proportion of their morbidity and mortality because of the resistance to therapeutic agents including corticosteroids. Its pathogenic mechanism is not known, but several studies have provided findings implicating that T-cells, especially activated CD8+ cells, may play essential roles, and thus could be therapeutic targets in this disease. To test this hypothesis, we began clinical investigation of the efficacy of T-cell-specific immunosuppressants, cyclosporine (CsA) and FK506, in PM/DM patients with ILD. In our retrospective nationwide multi-center study compiling a total of 53 patients, a combination of CsA and corticosteroids resulted in favorable early and long-term outcome in the majority of patients except for DM patients with acute ILD. In this subset, those who received the combination as an initial therapy had better survival than those who initially received corticosteroids alone. FK506 has a similar mode of action but is up to 100-fold more potent than CsA in vitro, and has been used in more refractory ILD cases. We next reviewed 5 PM/DM patients with ILD who failed on various immunosuppressants including CsA and were subsequently treated with FK506 in our hospital, and found that 3 improved promptly, 1 gradually and steadily, and another case responded slowly after prednisolone dose was increased. None developed adverse effects. In summary, these T-cell targeted therapies have a potential to be the cornerstone of the treatment for ILD in PM/DM patients. The combination therapy with CsA and corticosteroids may be efficacious especially when used early. FK506 may be advantageous even in refractory cases to CsA. These findings indicate that further investigation is warranted. Currently, prospective investigation of FK506 is underway.

Dermatomyositis↗
PubMed2005

Cognitive dysfunction in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune-mediated collagen disease that results in multiorgan failure. It is the collagen disease most frequently associated with neuropsychiatric symptoms, which have been hypothesized to stem from certain types of cognitive dysfunction. Subjects were 21 patients with SLE (one man, 20 women; aged 16-55 years; mean age, 35.1+/-10.7 years) who were undergoing treatment in the rheumatology unit of a general hospital, and 17 healthy control subjects matched to the patient group with respect to age and gender (two men, 15 women; mean age, 35.9+/-6.3 years). They were administered various tests of cognitive function including verbal reasoning, non-verbal reasoning, verbal memory, non-verbal memory, attention and mental flexibility, psychomotor speed and frontal lobe function. In addition, the SLE patients were tested for antiphospholipid antibodies. The SLE patients performed worse than the control group on immediate, delayed and interference of the Rey verbal test and paired associate tests of Wechsler Memory Scale, and their reaction time was slower in Trail A and Trail B tests. Moreover, these findings were more pronounced in the group with major neuropsychiatric symptoms. However, no relationship was apparent between these deficits in cognitive function and the presence or absence of antiphospholipid antibodies. The results suggest that verbal memory and psychomotor speed underlie the neuropsychiatric symptoms seen in SLE patients.

Adolescent↗
PubMed2005

Pulmonary exercise testing predicts prognosis in patients with chronic obstructive pulmonary disease.

OBJECTIVE: In patients with chronic obstructive pulmonary disease (COPD), patient age and initial value of forced expiratory volume in 1 second (FEV1) have been considered the most accurate predictors of mortality among the parameters obtained from pulmonary exercise tests. However, few studies have examined the predictive variables of prognosis among exercise parameters in COPD. We therefore attempted to identify the best index for predicting long-term survival in patients with COPD among the cardiopulmonary variables obtained during exercise testing. PATIENTS AND METHODS: Fifty-eight patients with COPD (50 men and 8 women) without hypoxemia at rest or other serious complications performed resting pulmonary function tests followed by a symptom-limited ramp exercise test on a cycle ergometer with breath-by-breath gas analysis and arterial blood gas sampling. RESULTS: After 3,570+/-1,373 days follow-up (mean+/-SD), 21 died because of deaths by respiratory failure. The overall survival rates calculated by the Kaplan-Meier method were 92.9% and 75.8% at 5 years and 10 years, respectively. In univariate Cox hazards analysis, age, FEV1, VC, RV/TLC, VEmax, VO2max, VCO2max, PaO2max, PacO2max, and PaO2 at rest were found to be significant prognostic indices of survival. However, multivariate analysis revealed only FEV1, PaO2max, and age as independent predictors of mortality. In severe COPD patients (FEV1 <50% predicted, n=35), PaO2max and age also correlated with prognosis, whereas FEV1 did not. CONCLUSION: Pulmonary exercise testing is useful in predicting prognosis in patients with COPD.

Aged↗
PubMed2005

[An autopsy case of intestinal Behcet's disease with sacroiliitis accompanied by myelodysplastic syndrome with trisomy 8. ].

Here we described an autopsy case of intestinal Behcet's disease with sacroiliitis associated with myelodysplastic syndrome (RAEB-t, 8+). Over twenty cases of Behcet's disease associated with myelodysplastic syndrome have been reported in preliterature so far. The majority of them are incomplete type of Behcet's disease having intestinal ulceration. Of those, trisomy 8 is the most common chromosomal abnormality. We reviewed similar cases reported and investigated the association of intestinal Behcet's disease with trisomy 8. The association of sacroiliitis with Behcet's disease is also studied.

Aged↗
PubMed2005

Abnormal regional cerebral blood flow in systemic lupus erythematosus patients with psychiatric symptoms.

OBJECTIVE: Single-photon emission computed tomography (SPECT) studies have demonstrated decreased regional cerebral blood flow (rCBF) in systemic lupus erythematosus (SLE) patients. However, no study has done voxel-based analysis using statistical parametric mapping (SPM) that can evaluate rCBF objectively, and the relationship between rCBF and psychiatric symptoms has not been well investigated. Using L,L-ethyl cysteinate dimer (99mTc ECD) SPECT and SPM, we aimed to clarify the association of rCBF changes with psychiatric symptoms in SLE patients whose magnetic resonance imaging (MRI) showed no morphological abnormalities. METHOD: Twenty SLE patients and 19 healthy volunteers underwent 99mTc ECD SPECT. Data were collected from August 2000 to March 2003. SLE was diagnosed according to American College of Rheumatology criteria, and psychiatric symptoms were diagnosed according to ICD-10 criteria. On the basis of the modified Carbotte, Denburg, and Denburg method, the patients were classified into 3 groups: a group with major psychiatric symptoms (hallucinosis, delusional disorder, and mood disorder), a group with minor psychiatric symptoms (anxiety disorder, dissociative disorder, and emotionally labile disorder), and a group without psychiatric symptoms. Gross organic lesions were ruled out by brain MRI. Group comparisons of rCBF were performed with analysis using SPM99. RESULTS: SLE patients without MRI lesions showed decreased rCBF in the posterior cingulate gyrus and thalamus. The reduction in rCBF was overt in patients with major psychiatric symptoms. CONCLUSION: Our study indicated that SLE patients may have dysfunction in the posterior cingulate gyrus and thalamus and that this may be associated with the severity of psychiatric symptoms.

Adolescent↗
PubMed2005

[CTLA4-Ig].

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Abatacept↗