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Dive into the research topics where Akira Murasawa is active.

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Featured researches published by Akira Murasawa.


Arthritis & Rheumatism | 2001

Development of fulminant hepatitis B (precore variant mutant type) after the discontinuation of low-dose methotrexate therapy in a rheumatoid arthritis patient.

Satoshi Ito; Kiyoshi Nakazono; Akira Murasawa; Yusaku Mita; Kojiro Hata; Noriko Saito; Masatoshi Kikuchi; Kazukiyo Yoshida; Masaaki Nakano; Fumitake Gejyo

A 75-year-old female rheumatoid arthritis patient who was positive for hepatitis B surface antigen and for antibodies to hepatitis Be antigen showed liver dysfunction, and therefore methotrexate (MTX) therapy was discontinued. Her drug lymphocyte stimulation test indicated positivity for MTX. Her liver dysfunction improved briefly, but she developed fulminant hepatitis with elevated levels of hepatitis B virus (HBV)/DNA polymerase and subsequently died. HBV/DNA analysis performed with polymerase chain reaction-mutation site-specific assay revealed that the fulminant hepatitis was caused by a precore mutant virus. Sudden reactivation of the immune system by discontinuation of MTX may have led to the attack on infected cells. Even when hepatitis Be antibodies are present, MTX should not be used in patients who have chronic infection with HBV.


Journal of Periodontology | 2012

Interleukin-6 Gene Promoter Methylation in Rheumatoid Arthritis and Chronic Periodontitis

Kohei Ishida; Tetsuo Kobayashi; Satoshi Ito; Yasutaka Komatsu; Tomoko Yokoyama; Moe Okada; Asami Abe; Akira Murasawa; Hiromasa Yoshie

BACKGROUND Methylation status of the cytokine genes may play a role in the pathogenesis of inflammatory diseases, such as rheumatoid arthritis (RA) and chronic periodontitis (CP). This study was undertaken to evaluate whether the DNA methylation profile of the interleukin-6 (IL-6) gene promoter was unique to individuals with RA and CP. METHODS The study participants consisted of 30 patients with RA, 30 patients with CP, and 30 age-, sex-, and smoking status-balanced healthy controls. Genomic DNA isolated from peripheral blood was modified by sodium bisulfite and analyzed for DNA methylation levels of IL-6 gene with direct sequencing. Levels of IL-6 were determined by an enzyme-linked immunosorbent assay. RESULTS The region of IL-6 gene promoter from -1200 to +27 bp was shown to contain 19 CpG motifs. The methylation levels of the CpG motif at -74 bp were significantly lower in patients with RA and CP than those in controls (P = 0.0001). Both levels of serum IL-6 and IL-6 production by mononuclear cells were significantly different between individuals with and without the methylation at -74 bp (P = 0.03). The +19 bp motif exhibited differential levels of the methylation among the groups, which was not associated with serum levels of IL-6. The other 17 CpG motifs exhibited comparable levels of the methylation between the groups. CONCLUSION These results suggest that hypomethylated status of a single CpG in the IL-6 promoter region may lead to increased levels of serum IL-6, implicating a role in the pathogenesis of RA and CP.


Clinical Rheumatology | 2002

Comparison of gastroduodenal, renal and abdominal fat biopsies for diagnosing amyloidosis in rheumatoid arthritis.

Takeshi Kuroda; Naohito Tanabe; Minoru Sakatsume; S. Nozawa; T. Mitsuka; Hajime Ishikawa; Chikako Takahashi Tohyama; Kiyoshi Nakazono; Akira Murasawa; Masaaki Nakano; Fumitake Gejyo

Abstract: The aim of the study was to determine the frequency of amyloidosis detected by gastroduodenal biopsy in rheumatoid arthritis (RA) patients, and to investigate correlations between the results of gastroduodenal biopsy and abdominal fat and renal biopsies. A total of consecutive 1006 RA patients underwent gastroduodenal biopsy. The 71 patients who tested positive for gastrointestinal (GI) amyloidosis were asked to undergo renal and abdominal fat biopsies, and 21 did so. Renal biopsies were also performed on 12 patients with no amyloidosis but indicators of drug-induced renal damage, and abdominal fat biopsies were performed on 50 RA patients with no indication of amyloidosis. The prevalence of GI amyloidosis was 7.1%. Urinary abnormalities and GI symptoms were common in GI amyloidisis, and inflammatory markers were elevated. Sixty-one (86%) had either depressed creatinine clearance or urinary symptoms. Nineteen of the 21 patients (91%) with GI amyloidosis who underwent renal biopsies also had renal amyloid deposits. Eleven of the 21 (52%) had amyloidosis on abdominal fat biopsy. None of the 12 patients without GI amyloidosis had renal amyloidosis on renal biopsy, and none of the 50 patients without GI amyloidosis had amyloidosis on abdominal fat biopsy. Gastroduodenal biopsy reveals a high prevalence of amyloidosis in RA patients. Amyloidosis is often associated with signs of renal impairment. Results of GI biopsy are highly correlated with those of renal biopsy, but the results of fat biopsy are not. We recommend GI biopsy for RA patients for the screening of systemic amyloidosis.


Journal of Periodontology | 2013

Periodontal Treatment Decreases Levels of Antibodies to Porphyromonas gingivalis and Citrulline in Patients With Rheumatoid Arthritis and Periodontitis

Moe Okada; Tetsuo Kobayashi; Satoshi Ito; Tomoko Yokoyama; Asami Abe; Akira Murasawa; Hiromasa Yoshie

BACKGROUND Porphyromonas gingivalis has been implicated as an etiologic agent of rheumatoid arthritis (RA) because of the expression of peptidylarginine deiminase. The present study evaluates whether periodontal treatment may affect serum antibodies to P. gingivalis and citrulline levels in relation to disease activity of RA. METHODS Fifty-five patients with RA were randomly assigned to receive oral hygiene instruction and supragingival scaling (treatment group, n = 26) or no periodontal treatment (control group, n = 29). Periodontal and rheumatologic parameters and serum levels of cytokine and inflammatory markers citrulline and immunoglobulin (Ig)G to P. gingivalis were examined at baseline and 8 weeks later. RESULTS Both groups did not differ statistically in any parameters except percentage of sites with probing depth and clinical attachment level ≥ 4 mm at baseline. The treatment group exhibited a significantly greater decrease in disease activity score including 28 joints using C-reactive protein (DAS28-CRP) (P = 0.02), serum levels of IgG to P. gingivalis hemin binding protein (HBP)35 (P = 0.04), and citrulline (P = 0.02) than the control group. Serum levels of IgG to P. gingivalis HBP35 were significantly correlated positively with those of anti-cyclic citrullinated peptide antibodies (P = 0.0002). The same correlation was obtained between serum levels of IgG to P. gingivalis-sonicated extracts and those of rheumatoid factor (P = 0.02). CONCLUSIONS These results suggest that supragingival scaling decreases DAS28-CRP and serum levels of IgG to P. gingivalis HBP35 and citrulline in patients with RA. These observations may reflect a role of P. gingivalis in the protein citrullination, which is related to the pathogenesis of RA.


Journal of Periodontology | 2011

Antibody responses to periodontopathic bacteria in relation to rheumatoid arthritis in Japanese adults.

Moe Okada; Tetsuo Kobayashi; Satoshi Ito; Tomoko Yokoyama; Yasutaka Komatsu; Asami Abe; Akira Murasawa; Hiromasa Yoshie

BACKGROUND Periodontopathic bacteria have been implicated as contributory to the etiology of rheumatoid arthritis (RA). Anticyclic citrullinated peptide (CCP) antibodies and rheumatoid factor (RF) were shown to be associated with RA. This study examines whether serum levels of antibodies to periodontopathic bacteria may affect clinical and laboratory profiles of RA. METHODS The study participants consisted of 80 patients with RA, and 38 age-, sex-, smoking status-, and periodontal condition-balanced healthy controls. After periodontal and rheumatologic examination, serum levels of immunoglobulin G (IgG) antibodies to Porphyromonas gingivalis (Pg), Prevotella intermedia, Aggregatibacter actinomycetemcomitans (Aa) (previously Actinobacillus actinomycetemcomitans), and Eikenella corrodens (Ec) and those of anti-CCP antibodies and RF were determined by an enzyme-linked immunosorbent assay. RESULTS Patients with RA showed significantly higher levels of anti-Pg and anti-CCP antibodies than controls (P = 0.04 and P <0.0001). In contrast, IgG responses to Aa and Ec in patients with RA were significantly lower than those in controls (P <0.0001 and P = 0.0001). Multiple logistic regression analysis revealed a significant association of anti-Pg and anti-Aa IgG responses with RA, after adjustment for age, sex, and smoking (P = 0.005 and P = 0.02). Anti-Pg titer displayed a significant correlation with RF levels, probing depth, and clinical attachment level (P = 0.03, P = 0.03, and P = 0.02). CONCLUSION These results suggest that serum levels of anti-Pg IgG antibodies were associated with RA, and might affect serum levels of RF and periodontal condition in patients with RA.


Journal of Periodontology | 2009

Cytokine Gene Polymorphisms Associated With Rheumatoid Arthritis and Periodontitis in Japanese Adults

Tetsuo Kobayashi; Akira Murasawa; Satoshi Ito; Kouji Yamamoto; Yasutaka Komatsu; Asami Abe; Takayuki Sumida; Hiromasa Yoshie

BACKGROUND Cytokines play a major role in the pathogenesis of rheumatoid arthritis (RA) and periodontitis. Both diseases were previously shown to be partly influenced by cytokine gene polymorphisms. Therefore, we evaluated whether the distributions of the cytokine genotypes were unique to subjects with both diseases. METHODS The study subjects consisted of Japanese adults with RA (RA group; n = 153), periodontitis only (P group; n = 117), and healthy individuals (H group; n = 108). Clinical periodontal condition was defined by measurements of probing depth, clinical attachment level, and bleeding on probing. Genomic DNA was isolated from peripheral blood and analyzed for the determination of 16 gene polymorphisms encoding interleukin (IL)-1, -2, -4, -6, and -10, tumor necrosis factor-alpha, and transforming growth factor-beta 1. RESULTS The frequency of patients with RA who exhibited periodontitis was 89.5% (RA + P group; n = 137). No significant differences were observed in any of the frequencies of cytokine genotypes and alleles among the subject groups. After adjustment for age, gender, and smoking status, multiple logistic regression analysis revealed a significant difference in the distribution of IL-1B +3954 genotypes between RA + P and P groups (P = 0.006) and between RA + P and H groups (P = 0.008). CONCLUSION Japanese individuals with RA and periodontitis may exhibit different distributions of IL-1B +3954 genotypes than healthy controls and subjects with periodontitis only.


Journal of Periodontology | 2014

Periodontal and serum protein profiles in patients with rheumatoid arthritis treated with tumor necrosis factor inhibitor adalimumab.

Tetsuo Kobayashi; Tomoko Yokoyama; Satoshi Ito; Daisuke Kobayashi; Akira Yamagata; Moe Okada; Ken Oofusa; Ichiei Narita; Akira Murasawa; Kiyoshi Nakazono; Hiromasa Yoshie

BACKGROUND Tumor necrosis factor (TNF)-α inhibitor has been shown to affect the periodontal condition of patients with rheumatoid arthritis (RA). The aim of the present study is to assess the effect of a fully humanized anti-TNF-α monoclonal antibody, adalimumab (ADA), on the periodontal condition of patients with RA and to compare serum protein profiles before and after ADA therapy. METHODS The study participants consisted of 20 patients with RA treated with ADA. Clinical periodontal and rheumatologic parameters and serum cytokine levels were evaluated at baseline and 3 months later. Serum protein spot volume was examined with two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis. Proteins with significant difference in abundance before and after ADA therapy were found and identified using mass spectrometry and protein databases. RESULTS The patients showed a significant decrease in gingival index (P = 0.002), bleeding on probing (P = 0.003), probing depth (P = 0.002), disease activity score including 28 joints using C-reactive protein (P <0.001), and serum levels of TNF-α (P <0.001) and interleukin-6 (P <0.001) after ADA medication, although plaque levels were comparable. Among a total of 495 protein spots obtained, nine spots were significantly decreased in abundance at reassessment, corresponding to complement factor H, phospholipase D, serum amyloid A, complement component 4, and α-1-acid glycoprotein (P <0.01). CONCLUSION These results suggest a beneficial effect of ADA therapy on the periodontal condition of patients with RA, which might be related to differences in serum protein profiles before and after ADA therapy.


Journal of Periodontology | 2014

Assessment of Interleukin-6 Receptor Inhibition Therapy on Periodontal Condition in Patients With Rheumatoid Arthritis and Chronic Periodontitis

Tetsuo Kobayashi; Moe Okada; Satoshi Ito; Daisuke Kobayashi; Kohei Ishida; Anri Kojima; Ichiei Narita; Akira Murasawa; Hiromasa Yoshie

BACKGROUND Overproduction of interleukin (IL)-6 may play a pathologic role in rheumatoid arthritis (RA) and chronic periodontitis (CP). The present study assesses IL-6 receptor (IL-6R) inhibition therapy on the periodontal condition of patients with RA and CP. METHODS The study participants were 28 patients with RA and CP during treatment with IL-6R inhibitor, and 27 patients with RA and CP during treatment without IL-6R inhibitor. Periodontal and rheumatologic parameters and serum levels of cytokine and inflammatory markers and immunoglobulin G against periodontopathic bacteria were examined after medication with IL-6R inhibitor for 20.3 months on average (T1) and again 8 weeks later (T2). RESULTS No differences were observed between the groups in any parameter values at T1, except for serum IL-6 levels. The anti-IL-6R group showed a significantly greater decrease in gingival index, bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), and serum levels of IL-6 and matrix metalloproteinase (MMP)-3 from T1 to T2 than the control group (P <0.05). A significant correlation was found between changes in serum anticyclic citrullinated peptide levels and those in PD and CAL in the anti-IL-6R group (P <0.05), whereas both groups exhibited a significant association between changes in serum MMP-3 levels and those in BOP (P <0.05). CONCLUSION Changes in periodontal and serum parameter values were different between the patients with RA and CP during treatment with and without IL-6R inhibitor.


Journal of Arthroplasty | 1997

SURVIVORSHIP ANALYSIS OF TOTAL KNEE ARTHROPLASTY WITH THE KINEMATIC PROSTHESIS IN PATIENTS WHO HAVE RHEUMATOID ARTHRITIS

Tadamasa Hanyu; Akira Murasawa; Takeshi Tojo

Eighty-eight primary total knee arthroplasty procedures in 61 patients with rheumatoid arthritis were performed using the Kinematic total knee prosthesis (Howmedica, Rutherford, NJ) with cement between 1980 and 1985. No patients were lost to follow-up evaluation. Thirty-one of 61 patients died during the study period. Survivorship for all patients by life-table method was estimated as 56% at 10 years. This was shorter than the expected survival rate of a sex- and age-matched control group. Fifty procedure outcomes in 34 patients (27 women, 7 men) who were followed for more than 10 years were available for clinical evaluation. Complications occurred in 11 cases; in 4 of these, revision surgery was required. With revision as the endpoint, the survival rate of the prostheses was estimated as 93% at 10 years.


Journal of Periodontal Research | 2016

Expression of anti-Porphyromonas gingivalis peptidylarginine deiminase immunoglobulin G and peptidylarginine deiminase-4 in patients with rheumatoid arthritis and periodontitis

Atsushi Shimada; Tetsuo Kobayashi; Satoshi Ito; Moe Okada; Akira Murasawa; Kiyoshi Nakazono; Hiromasa Yoshie

BACKGROUND AND OBJECTIVE Autoimmunity against citrullinated proteins through peptidylarginine deiminase (PAD) may be involved in the pathophysiology of rheumatoid arthritis (RA). The present study evaluated the serum levels of antibodies to citrullinated proteins and to Porphyromonas gingivalis PAD (PPAD), and the endogenous expression of PAD-4, in individuals with and without RA, as well as before and after periodontal treatment. MATERIAL AND METHODS The study participants consisted of 52 patients with RA (RA group) and 26 age-, gender- and smoking status-matched healthy controls (non-RA group). Of the 52 patients, 26 were randomly assigned to receive oral hygiene instruction and supragingival scaling (RA subgroup). After periodontal and rheumatologic assessments, the serum levels of anti-cyclic citrullinated peptide (CCP) immunoglobulin G (IgG), anti-PPAD IgG and PAD-4 were determined using ELISA. RESULTS The serum levels of anti-CCP IgG and anti-PPAD IgG were significantly higher in the RA group than in the non-RA group (p < 0.001 and p = 0.03). A significant, positive correlation was observed between the serum levels of anti-PPAD IgG and anti-CCP IgG (p = 0.04), but not between the serum levels of PAD-4 and anti-CCP IgG. Multiple logistic regression analyses revealed a significant association between anti-PPAD IgG responses and RA after adjustment for age, gender and smoking (p = 0.004). Supragingival scaling significantly improved the periodontal condition and disease activity of RA (p < 0.05), but failed to decrease the serum levels of anti-CCP IgG, anti-PPAD IgG and PAD-4 after 2 mo of treatment. CONCLUSION These results might suggest an association between anti-PPAD IgG and anti-CCP IgG responses, implicating a role for PPAD in protein citrullination in patients with RA and periodontitis.

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