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Dive into the research topics where Masahiro Yokosawa is active.

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Featured researches published by Masahiro Yokosawa.


Modern Rheumatology | 2015

Efficacy and safety of abatacept for patients with Sjögren's syndrome associated with rheumatoid arthritis: Rheumatoid Arthritis with Orencia Trial toward Sjögren's syndrome Endocrinopathy (ROSE) trial—an open-label, one-year, prospective study—Interim analysis of 32 patients for 24 weeks

Hiroto Tsuboi; Isao Matsumoto; Shinya Hagiwara; Tomoya Hirota; Hiroyuki Takahashi; Hiroshi Ebe; Masahiro Yokosawa; Chihiro Hagiya; Hiromitsu Asashima; C. Takai; Haruka Miki; Naoto Umeda; Yuya Kondo; Hiroshi Ogishima; T. Suzuki; Shintaro Hirata; Kazuyoshi Saito; Yoshiya Tanaka; Yoshiro Horai; Hideki Nakamura; Atsushi Kawakami; Takayuki Sumida

Abstract Objective. To assess the efficacy and safety of abatacept for secondary Sjögrens syndrome (SS) associated with rheumatoid arthritis (RA). Methods. The primary endpoint of this 1-year, open-labeled, prospective, observational multicenter study of RA-associated secondary SS was the rate of SDAI remission at 52 weeks after initiation of abatacept therapy. The secondary endpoints included that of Saxsons test and Schirmers test. Adverse events during the study period were also analyzed. Results. Thirty-two patients (all females) were enrolled in this study. Interim analysis at 24 weeks included assessment of efficacy (n = 31) and safety (n = 32). The mean SDAI decreased from 19.8 ± 11.0 (± SD) at baseline to 9.9 ± 9.9 at 24 weeks (P < 0.05). Patients with clinical remission, as assessed by SDAI, increased from 0 patient (0 week) to 8 patients (25.8%) at 24 weeks. Saliva volume (assessed by Saxsons test) increased slightly from 2232 ± 1908 (0 week) to 2424 ± 2004 (24 weeks) mg/2 min (n = 29). In 11 patients with Greenspan grading 1/2 of labial salivary glands biopsy, saliva volume increased from 2945 ± 2090 (0 week) to 3419 ± 2121 (24 weeks) mg/2 min (P < 0.05). Schirmers test for tear volume showed increase from 3.6 ± 4.6 (0 week) to 5.5 ± 7.1 (24 weeks) mm/5 min (n = 25; P < 0.05). Five adverse events occurred in five of 32 patients (15.6%), and three of these events were infections. Conclusion. Abatacept seems to be effective for both RA and RA-related secondary SS.


Modern Rheumatology | 2014

Primary and secondary surveys on epidemiology of Sjögren's syndrome in Japan

Hiroto Tsuboi; Hiromitsu Asashima; C. Takai; Shinya Hagiwara; Chihiro Hagiya; Masahiro Yokosawa; Tomoya Hirota; Hisanori Umehara; Atsushi Kawakami; Hideki Nakamura; Hajime Sano; Kazuo Tsubota; Yoko Ogawa; Etsuko Takamura; Ichiro Saito; Hiroko Inoue; Seiji Nakamura; Masafumi Moriyama; Tsutomu Takeuchi; Yoshiya Tanaka; Shintaro Hirata; Tsuneyo Mimori; Hajime Yoshifuji; Akiko Ohta; Isao Matsumoto; Takayuki Sumida

Abstract Objective. To characterize the epidemiology of Sjögrens syndrome (SS), including prevalence, disease type, extra-glandular involvement, satisfaction of diagnostic criteria sets, and treatment used in Japan. Methods. The Research Team for Autoimmune Diseases, the Research Program for Intractable Disease by the Ministry of Health, Labor and Welfare conducted primary and secondary surveys on epidemiology of SS in 2011. The primary survey covered 4,729 out of 14,095 Japan-wide Hospital Departments to investigate the prevalence of SS. The secondary survey encompassed 214 Hospital Departments that agreed to the survey, to characterize disease type, extra-glandular involvement, satisfaction of diagnostic criteria sets, and treatments. Results. The number of patients with SS in Japan estimated by the primary survey was 68,483. The secondary survey involving data collected from 2,195 SS patients from 98 Hospital Departments showed that the mean age of patients was 60.8 ± 15.2 years, male/female ratio was 1/17.4, primary/secondary SS was about 60%/40% and glandular/extra-glandular form in primary SS was about 70%/25%. The satisfaction rate was 53.8% for the 1999 revised Japanese Ministry of Health criteria for the diagnosis of SS, 47.7% for the 2002 American–European Consensus Group classification criteria for SS and 49.6% for 2012 American College of Rheumatology classification criteria for SS. Corticosteroids were used by 752 of 2,195 patients (34%), immunosuppressants by 358 patients (16%), biologics by 68 patients (3%) and secretagogues by 695 patients (32%). Conclusion. The surveys provided valuable information on the epidemiology of SS including prevalence, disease type, extra-glandular involvement, satisfaction of diagnostic criteria sets and treatments used today in Japan.


Modern Rheumatology | 2014

Clinicopathological features of IgG4-related disease complicated with orbital involvement

Chihiro Hagiya; Hiroto Tsuboi; Masahiro Yokosawa; Shinya Hagiwara; Tomoya Hirota; C. Takai; Hiromitsu Asashima; Haruka Miki; Naoto Umeda; Masanobu Horikoshi; Yuya Kondo; Makoto Sugihara; Hiroshi Ogishima; T. Suzuki; Takahiro Hiraoka; Yuichi Kaji; Isao Matsumoto; Tetsuro Oshika; Takayuki Sumida

Abstract Objective. IgG4-related disease (IgG4-RD) is characterized by IgG4-positive plasmacytic infiltration and fibrosis in various organs. Orbital involvement in IgG4-RD includes lacrimal glands, extra-ocular muscles, trigeminal nerve and other parts of the orbit. Immunohistochemical staining is used to diagnose IgG4-RD in patients with orbital inflammation. The purpose of this retrospective study was to clarify the clinicopathological features of IgG4-RD complicated with orbital involvement. Methods. We examined the clinical features, pathological findings and response to treatment in nine patients with IgG4-RD who underwent orbital tissue biopsy between April 2010 and August 2012 at the University of Tsukuba Hospital. Results. Among the nine patients, eight had dacryoadenitis, one had infraorbital nerve swelling, and another one had IgG4-related orbital inflammation. Involvement of other organs was identified in all patients, including involvement of the salivary glands, lymph nodes, lung, kidney and para-aorta. In all patients, biopsy samples from orbital tissues showed lymphoplasmacytic infiltration and fibrosis, and IgG4-positive/IgG-positive plasmacyte ratio of > 40%. All patients were treated with prednisolone (0.6 mg/kg/day) and responded well in early phase, although relapse was noted in two patients following tapering of prednisolone, evident by swelling of lacrimal glands. Conclusion. Patients with IgG4-RD complicated with orbital involvement often present with involvement of other organs. The histopathological findings of orbital tissue match the characteristic features of IgG4-RD. Corticosteroid is effective for orbital and systemic involvement in IgG4-RD.


Modern Rheumatology | 2016

Effectiveness of abatacept for patients with Sjögren’s syndrome associated with rheumatoid arthritis. An open label, multicenter, one-year, prospective study: ROSE (Rheumatoid Arthritis with Orencia Trial toward Sjögren’s syndrome Endocrinopathy) trial

Hiroto Tsuboi; Isao Matsumoto; Shinya Hagiwara; Tomoya Hirota; Hiroyuki Takahashi; Hiroshi Ebe; Masahiro Yokosawa; Mizuki Yagishita; Hidenori Takahashi; Izumi Kurata; Ayako Ohyama; Fumika Honda; Hiromitsu Asashima; Haruka Miki; Naoto Umeda; Yuya Kondo; Shintaro Hirata; Kazuyoshi Saito; Yoshiya Tanaka; Yoshiro Horai; Hideki Nakamura; Atsushi Kawakami; Takayuki Sumida

Abstract Objective: To clarify the efficacy and safety of abatacept for secondary Sjögren’s syndrome (SS) associated with rheumatoid arthritis (RA). Methods: The primary endpoint of this open-labeled, prospective, observational multicenter study for secondary SS with RA was the remission rate of Simplified Disease Activity Index (SDAI) at 52 weeks after initiation of abatacept. The secondary endpoints included Saxon’s test and Schirmer’s test. Adverse events and adherence rate during the study period were also analyzed. Results: Thirty-six patients (all females) were enrolled in this study. The mean SDAI decreased significantly from 20.6 ± 11.2 (±SD) at baseline to 10.0 ± 10.5 at 52 weeks (p < 0.05). Patients with SDAI remission increased from 0 (0 week) to 12 patients (33.3%) at 52 weeks. Saliva volume assessed by Saxon’s test increased significantly from 2136 ± 1809 (0 week) to 2397 ± 1878 (24 weeks) mg/2 min (n = 34, p < 0.05). Saliva volume increased significantly from 2945 ± 2090 (0 week) to 3419 ± 2121 (24 weeks) mg/2 min in 11 patients with Greenspan grade 1 or 2 of labial salivary gland biopsy (p < 0.05), but no change was noted in 18 patients with Greenspan grade 3 or 4. Tear volume by Schirmer’s test increased significantly from 4.2 ± 4.8 (0 week) to 6.4 ± 7.8 (24 weeks) mm/5 min (n = 30, p < 0.05). The adherence rate to abatacept was 80.6% (29/36) over the 52-week period. Twelve adverse events occurred in 10 of the 36 patients, and 7 of these events were infections. Conclusion: Abatacept seems to be effective for both RA and SS related manifestations.


Modern Rheumatology | 2015

Clinical features of patients with IgG4-related disease complicated with perivascular lesions

Hiroshi Ebe; Hiroto Tsuboi; Chihiro Hagiya; Hiroyuki Takahashi; Masahiro Yokosawa; Shinya Hagiwara; Tomoya Hirota; Yuko Kurashima; C. Takai; Haruka Miki; Hiromitsu Asashima; Naoto Umeda; Yuya Kondo; Hiroshi Ogishima; T. Suzuki; Yusuke Chino; Isao Matsumoto; Takayuki Sumida

Abstract Objective. To define the clinical features of IgG4-related disease (IgG4-RD) complicated with perivascular lesions. Methods. The clinical features of seven patients with IgG4-RD and perivascular lesions diagnosed at the University of Tsukuba Hospital between October 2008 and October 2013, were analyzed, including clinical background, results of imaging studies, satisfaction of the 2011 comprehensive diagnostic criteria (CDC) for IgG4-RD, laboratory data, distribution of perivascular lesions, involvement of other organs, and response to steroid therapy. Results. We studied six men and one woman with a mean age of 66.9 ± 6.7 years (± SD). Six of seven patients were diagnosed as definite IgG4-RD, while the seventh was considered possible IgG4-RD, based on the CDC for IgG4-RD. Serum IgG4 levels at diagnosis were higher than 135 mg/dl in all seven patients (mean, 933 ± 527). Serum C-reactive protein (CRP) levels were elevated in two only (mean, 1.42 ± 3.56 mg/dl). The perivascular lesions were located in the pulmonary artery (n = 1), thoracic aorta (n = 2), abdominal aorta (n = 6), coronary (n = 1), celiac (n = 1), superior mesenteric (n = 1), renal (n = 2), inferior mesenteric (n = 5), and iliac (n = 3) arteries. In addition to perivascular lesions, six patients showed involvement of other organs. All seven patients were treated with prednisolone (0.6 mg/kg/day), which rapidly improved the perivascular and other organ lesions in six patients (the other one patient have not yet been evaluated due to the short follow-up). Conclusion. Perivascular lesions show wide distribution in patients with IgG4-RD. Serum CRP levels are not necessarily elevated in these patients. Steroid therapy is effective in IgG4-RD and results in resolution of lesions.


Modern Rheumatology | 2016

Evaluation of changes in magnetic resonance images following 24 and 52 weeks of treatment of rheumatoid arthritis with infliximab, tocilizumab, or abatacept

Tomoya Hirota; T. Suzuki; Hiroshi Ogishima; Shinya Hagiwara; Hiroshi Ebe; Hiroyuki Takahashi; Masahiro Yokosawa; Naoto Umeda; Yuya Kondo; Hiroto Tsuboi; Isao Matsumoto; Takayuki Sumida

Objectives. To compare MRI findings in rheumatoid arthritis (RA) patients treated with biologic disease-modifying anti-rheumatic drugs (DMARDs). Methods. The study subjects were 43 RA patients treated with biologic DMARDs (13 with infliximab, 15 with tocilizumab, and 15 with abatacept). They were evaluated using Simplified Disease Activity Index (SDAI) and low-field extremity MRI at baseline, and at 24 weeks and 52 weeks of treatment. Results. Synovitis scores were significantly lower by 24 weeks in all groups, compared with baseline (P < 0.05). Significant improvement in bone marrow edema (BME) scores were noted from baseline to 24 weeks in infliximab and abatacept groups (P < 0.05), but from 24 weeks to 52 weeks in tocilizumab group (P < 0.01). No significant change was found in erosion score. The synovitis score at baseline correlated significantly with SDAI at 24 weeks (P < 0.05), and the score at 24 weeks correlated significantly with SDAI at 52 weeks (P < 0.05). Conclusions. The results suggest that the inflammatory improvement by infliximab and abatacept may express earlier than those by tocilizumab, despite similar improvement in SDAI. MRI-detected synovitis could be a useful predictor of SDAI at 24 weeks of treatment. The MRI remains the best tool to detect and assess the effects of biologic DMARDs in RA.


Modern Rheumatology | 2015

Usefulness of MR imaging of the parotid glands in patients with secondary Sjögren's syndrome associated with rheumatoid arthritis

Masahiro Yokosawa; Hiroto Tsuboi; Katsuhiro Nasu; Chihiro Hagiya; Shinya Hagiwara; Tomoya Hirota; Hiroshi Ebe; Hiroyuki Takahashi; Hiromitsu Asashima; Yuya Kondo; Hiroshi Ogishima; T. Suzuki; Manabu Minami; Hiroki Bukawa; Isao Matsumoto; Takayuki Sumida

Abstract Objective. To assess the correlation between MR imaging (MRI) of parotid glands with X-ray sialography, histopathology of the labial salivary glands, and salivary secretion, in patients with secondary Sjögrens syndrome (SS) associated with rheumatoid arthritis (RA). Methods. Non-contrast MRI of the parotid glands was performed in 13 secondary SS patients associated with RA who satisfied the revised Japanese diagnostic criteria for SS (1999), and the ACR/EULAR classification criteria for RA (2010). The MRI findings were classified according to the degree of high-intensity signal on T1-weighted images (T1WI) and short inversion time inversion recovery (STIR) images into five grades (0–4), using the modified Nagasaki University grading method. The results of MRI grading were compared with the Rubin and Holt staging of X-ray sialography (0–4), the Greenspan grading of labial salivary gland histopathology (0–4), and salivary secretion by the gum test (ml/10 min). Results. All 13 patients were females, with a mean age of 50.2 ± 11.3 years. According to the MRI grading, 3 patients were Grade 1, 5 were Grade 2, 5 were Grade 3, and none was Grade 0 or Grade 4. The mean stage by X-ray sialography was 1.7 ± 1.0, the mean grade by histopathology was 2.4 ± 1.2, and the mean volume of salivary secretion was 9.7 ± 3.9 ml. The MRI grading correlated significantly with the Rubin and Holt staging and Greenspan grading (P < 0.01 each, Spearmans rank correlation), and significantly and inversely with the results of the gum test (P < 0.05). Conclusion. The results suggest that MRI of the parotid glands is a useful noninvasive tool for evaluating destruction and inflammation in the salivary glands.


Lupus | 2015

Predictors of the response to treatment in acute lupus hemophagocytic syndrome

Hiroyuki Takahashi; Hiroto Tsuboi; Izumi Kurata; S Inoue; Hiroshi Ebe; Masahiro Yokosawa; Shinya Hagiwara; Tomoya Hirota; Hiromitsu Asashima; Syunta Kaneko; Hoshimi Kawaguchi; Yuko Kurashima; Haruka Miki; Naoto Umeda; Yuya Kondo; Hiroshi Ogishima; T. Suzuki; Isao Matsumoto; Takayuki Sumida

Objective The objective of this paper is to identify predictors for the response to treatment of acute lupus hemophagocytic syndrome (ALHS). Methods We reviewed seven cases with ALHS admitted to our hospital and published ALHS cases identified in the 2001–2014 Medline database, and then conducted univariate and multivariate analyses to identify predictors for the response to treatment. Results Review of our cases showed a significant and negative correlation between serum ferritin and anti-DNA antibody (p = 0.0025). All three patients treated with cyclosporine A (CsA) were considered responders despite high serum ferritin and corticosteroid resistance. We also reviewed 93 patients with ALHS identified in 46 articles. Multiple logistic regression analysis identified C-reactive protein (CRP) (OR 0.83, p = 0.042) and hemoglobin (OR 1.53, p = 0.026) measured at diagnosis of ALHS as significant predictors of the response to corticosteroid monotherapy. Moreover, among 32 patients treated with CsA, serum ferritin was significantly higher in CsA responders (12163 ± 16864 µg/l, n = 22) than in non-responders (3456 ± 6267/µg/l, p = 0.020, n = 10). Leukocyte count was significantly lower in the CsA responders (1940.0 ± 972.3/µl) than in the non-responders (3253 ± 2198/µl, p = 0.034). Conclusion Low CRP and high hemoglobin can predict a positive response to corticosteroid monotherapy while high serum ferritin and low leukocyte count can predict a positive response to CsA in patients with ALHS and therefore, when corticosteroid monotherapy is not effective in such cases, CsA could be the first choice of an additional immunosuppressive agent.


Arthritis Research & Therapy | 2015

Involvement of RORγt-overexpressing T cells in the development of autoimmune arthritis in mice

Yuya Kondo; Zhaojin Yao; Masahiro Tahara; Mana Iizuka; Masahiro Yokosawa; Shunta Kaneko; Seiji Segawa; Hiroto Tsuboi; Keigyou Yoh; Satoru Takahashi; Isao Matsumoto; Takayuki Sumida

IntroductionDifferentiation of T helper 17 cells is dependent on the expression of transcription retinoid-related orphan receptor gamma t (RORγt). The purpose of our study is to determine the role of RORγt expression in T cells on the development of collagen-induced arthritis (CIA).MethodsCIA was induced in C57BL/6 and T cell-specific RORγt transgenic (RORγt Tg) mice. At day 10 post-1st-immunization, lymph node (LN) cells were cultured with type II collagen (CII), and the expression levels of various cytokines and transcription factors on CD4+ T cells were measured. Total cells or CD4+ cells of draining LN were harvested from each mouse group after CII-immunization and transferred into C57BL/6 mice, and then CIA was induced in recipient mice. The expression levels of RORγt and other surface antigens, and the production of cytokines were analyzed in forkhead box P3 (Foxp3)+ regulatory T (Treg) cells. Foxp3+ Treg cells were analyzed for suppressive activity against proliferation of effector CD4+ T cells. Interlukin (IL)-10 neutralizing antibody was administrated in the course of CIA.ResultsCIA was significantly suppressed in RORγt Tg mice compared with C57BL/6 mice. RORγt expression and IL-17 production were significantly higher in CII-reactive CD4+ T cells from RORγt Tg mice. Arthritis was significantly attenuated in C57BL/6 mice recipient of cells from RORγt Tg mice. Most of Foxp3+ Treg cells expressed RORγt, produced IL-10 but not IL-17, and overexpressed CC chemokine receptor 6 (CCR6) and surface antigens related to the suppressive activity of Foxp3+ Treg cells in RORγt Tg mice. In vitro suppression assay demonstrated significant augmentation of the suppressive capacity of Foxp3+ Treg cells in RORγt Tg mice. CIA was exacerbated in both C57BL/6 mice and RORγt Tg mice by the treatment of anti-IL-10 antibody.ConclusionOur results indicated that RORγt overexpression in T cells protected against the development of CIA. The protective effects were mediated, at least in part, through the anti-inflammatory effects including high production of IL-10 of RORγt+Foxp3+ Treg cells.


Clinical and Experimental Immunology | 2016

The regulatory role of IFN-γ producing gammadelta T cells via the suppression of Th17 cell activity in bleomycin-induced pulmonary fibrosis

Seiji Segawa; Daisuke Goto; Akira Iizuka; Syunta Kaneko; Masahiro Yokosawa; Yuya Kondo; Isao Matsumoto; Takayuki Sumida

Interstitial pneumonia (IP) is a chronic progressive interstitial lung disease associated with poor prognosis and high mortality. However, the pathogenesis of IP remains to be elucidated. The aim of this study was to clarify the role of pulmonary γδT cells in IP. In wild‐type (WT) mice exposed to bleomycin, pulmonary γδT cells were expanded and produced large amounts of interferon (IFN)‐γ and interleukin (IL)‐17A. Histological and biochemical analyses showed that bleomycin‐induced IP was more severe in T cell receptor (TCR‐δ‐deficient (TCRδ–/–) mice than WT mice. In TCRδ–/– mice, pulmonary IL‐17A+CD4+ Τ cells expanded at days 7 and 14 after bleomycin exposure. In TCRδ–/– mice infused with γδT cells from WT mice, the number of pulmonary IL‐17A+ CD4+ T cells was lower than in TCRδ–/– mice. The examination of IL‐17A–/– TCRδ–/– mice indicated that γδT cells suppressed pulmonary fibrosis through the suppression of IL‐17A+CD4+ T cells. The differentiation of T helper (Th)17 cells was determined in vitro, and CD4+ cells isolated from TCRδ–/– mice showed normal differentiation of Th17 cells compared with WT mice. Th17 cell differentiation was suppressed in the presence of IFN‐γ producing γδT cells in vitro. Pulmonary fibrosis was attenuated by IFN‐γ‐producing γδT cells through the suppression of pulmonary IL‐17A+CD4+ T cells. These results suggested that pulmonary γδT cells seem to play a regulatory role in the development of bleomycin‐induced IP mouse model via the suppression of IL‐17A production.

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