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Dive into the research topics where Hazuki Takato is active.

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Featured researches published by Hazuki Takato.


Lung Cancer | 2013

Transformation to small-cell lung cancer following treatment with EGFR tyrosine kinase inhibitors in a patient with lung adenocarcinoma.

Satoshi Watanabe; Takashi Sone; Tomoharu Matsui; Kenta Yamamura; Mayuko Tani; Akihito Okazaki; Koji Kurokawa; Yuichi Tambo; Hazuki Takato; Noriyuki Ohkura; Yuko Waseda; Nobuyuki Katayama; Kazuo Kasahara

We report the case of a 52-year-old woman with lung adenocarcinoma treated with EGFR tyrosine kinase inhibitor (TKI) therapy. After disease progression, histological examination of a secondary biopsy specimen revealed small-cell lung cancer (SCLC) that was sensitive to standard SCLC treatment. Tumor markers, including ProGRP and NSE, were elevated. Transformation to SCLC is a mechanism for acquired resistance to EGFR-TKI therapy. Secondary biopsy is important for evaluation of genetic and histological changes and selection of appropriate treatment. Furthermore, ProGRP and NSE may be useful for early detection of SCLC transformation in cases resistant to EGFR-TKI therapy.


Experimental Lung Research | 2011

The specific chymase inhibitor TY-51469 suppresses the accumulation of neutrophils in the lung and reduces silica-induced pulmonary fibrosis in mice

Hazuki Takato; Masahide Yasui; Yukari Ichikawa; Yuko Waseda; Kanako Inuzuka; Yoriko Nishizawa; Atsuro Tagami; Masaki Fujimura; Shinji Nakao

ABSTRACT Chymase is a chymotrypsin-like serine protease that is present in mast cells. Its activities include various effects associated with inflammatory responses. But little is known about the effects of chymase in pulmonary fibrosis. The mouse silicosis model was induced by intratracheal injection of 10 mg silica. The Ashcroft pathological score and the hydroxyproline content of lungs were measured to evaluate the effect of a chymase inhibitor, 2-[4-(5-fluoro-3-methylbenzo[b]thiophen-2-yl)sulfonamido-3-methanesulfonylphenyl] thiazole-4-carboxylic acid (TY-51469). The cellular composition and cytokine levels in bronchoalveolar lavage fluid (BALF) were also examined. Following TY-51469 treatment, the lung fibrosis score and hydroxyproline level were significantly reduced, and the number of neutrophils and the levels of macrophage inflammatory protein-2, monocyte chemoattractant protein-1, and transforming growth factor-β1 in BALF were reduced on day 21. The administration of TY-51469 at an early stage showed a greater reduction of fibrosis compared to administration at a later stage. The neutrophil number in BALF in mice treated with TY-51469 both at an early stage and late stage was significantly reduced. The level of mouse mast cell proteinase-4 mRNA increased with time in silica-induced fibrosing lung tissue. These results show that the chymase inhibitor TY51469 suppresses the migration of neutrophils, which results in the suppression of lung fibrosis.


Respiratory Research | 2008

Angiotensin II type 2 receptor antagonist reduces bleomycin-induced pulmonary fibrosis in mice

Yuko Waseda; Masahide Yasui; Yoriko Nishizawa; Kanako Inuzuka; Hazuki Takato; Yukari Ichikawa; Atsuro Tagami; Masaki Fujimura; Shinji Nakao

BackgroundThe role of angiotensin II type 2 receptor (AT2) in pulmonary fibrosis is unknown. To evaluate the influence of angiotensin II type 1 receptor (AT1) and AT2 antagonists in a mouse model of bleomycin (BLM)-induced pulmonary fibrosis.MethodsWe examined effects of the AT1 antagonist (AT1A) olmesartan medoxomil (olmesartan) and the AT2 antagonist (AT2A) PD-123319 on BLM-induced pulmonary fibrosis, which was evaluated by Ashcrofts pathological scoring and hydroxyproline content of lungs. We also analyzed the cellular composition and cytokine levels in bronchoalveolar lavage fluid (BALF).ResultsWith olmesartan, the lung fibrosis score and hydroxyproline level were significantly reduced, and lymphocyte and neutrophil counts and tumor necrosis factor (TNF)-α levels in BALF were reduced on day 7. On day 14, macrophage and lymphocyte counts in BALF were reduced, accompanied by a reduction in the level of transforming growth factor (TGF)-β1. With PD-123319, the lung fibrosis score and hydroxyproline level were reduced. On day 7, macrophage, lymphocyte, and neutrophil counts in BALF were reduced, accompanied by reductions in TNF-α and monocyte chemoattractant protein (MCP)-1 levels. On day 14, macrophage, lymphocyte, and neutrophil counts in BALF were also reduced, accompanied by a reduction in the level of macrophage inflammatory protein (MIP)-2 level but not TGF-β1.ConclusionBoth AT1 and AT2 are involved in promoting interstitial pneumonia and pulmonary fibrosis via different mechanisms of action.


Respiratory Medicine | 2013

Pulmonary manifestations of anti-ARS antibody positive interstitial pneumonia – With or without PM/DM

Hazuki Takato; Yuko Waseda; Satoshi Watanabe; Kanako Inuzuka; Nobuyuki Katayama; Yukari Ichikawa; Masahide Yasui; Masaki Fujimura

BACKGROUND Autoantibodies against aminoacyl-tRNA synthetases (ARS) have been found to be highly specific for polymyositis and dermatomyositis (PM/DM) and to correlate strongly with complicating interstitial pneumonia (IP). The aim of the present study was to compare the clinical presentations of anti-ARS antibody-positive IP patients with or without manifestations of PM/DM. METHODS We retrospectively examined 36 IP patients with anti-ARS antibodies. Sixteen patients presented with and 20 without the features of PM/DM. They were divided into PM/DM-IP and idiopathic-IP (IIP) groups. Clinical symptoms, findings on physical examination, laboratory data, pulmonary function, computed tomography (CT), and bronchoalveolar lavage fluid (BALF) cell counts were compared. RESULTS Skin findings, myalgia, and elevation of serum creatinine kinase were found in the PM/DM-IP group. Features common to both groups included: volume loss in lower bilateral lobes; ground-glass opacities, reticular shadows and traction bronchiectasis on chest CT; high percentage of lymphocytes (IIP: 44.0% ± 21.0% (mean ± SD), PM/DM-IP: 50.5% ± 23.5%) and low CD4/8 ratios (IIP: 0.36 ± 0.34, PM/DM-IP: 0.44 ± 0.42) in BALF; decreased pulmonary function, including percentage of predicted vital capacity (VC) (IIP: 80.1% ± 15.4%, PM/DM-IP: 73.6% ± 16.4%), residual volume (RV) (IIP: 70.7% ± 21.7%, PM/DM-IP: 71.5% ± 17.1%), total lung capacity (TLC) (IIP: 73.4% ± 13.6%, PM/DM-IP: 71.6% ± 13.0%), and diffusing capacity DLco (IIP: 57.5% ± 26.7%, PM/DM-IP: 46.4% ± 10.3%). Both groups achieved good responses to initial corticosteroid or immunosuppressant therapy. CONCLUSION Patients with anti-ARS antibody-positive IP have common pulmonary manifestations regardless of the presence of PM/DM.


Allergology International | 2008

Sputum Eosinophilia, Airway Hyperresponsiveness and Airway Narrowing in Young Adults with Former Asthma

Johsuke Hara; Masaki Fujimura; Shigeharu Myou; Toshiyuki Kita; Miki Abo; Nobuyuki Katayama; Shiho Furusho; Kouichi Nobata; Yoshitaka Oribe; Hideharu Kimura; Takashi Sone; Yuko Waseda; Yukari Ichikawa; Tomoyuki Araya; Noriyuki Ohkura; Shunichi Tamori; Hazuki Takato; Yuichi Tambo; Yoriko Herai; Akihiro Hori; Masahide Yasui; Kazuo Kasahara; Shinji Nakao

BACKGROUND 30-80% of outgrown asthma subjects develop symptoms again later in life. We investigated inflammation and function of lower airway in adolescents with former asthma. METHODS 326 never-smoking young adults (mean age 24.0 years) were interviewed with special emphasis on history of asthma. Diagnosis of asthma was based on GINA guidelines. Former asthma subjects consisted of ones with a history of physician-diagnosed childhood asthma, who had been free of asthma symptoms without the use of medication for at least 10 years prior to the study. Provocative concentration of methacholine causing a 20% fall in forced expiratory volume in 1 second (FEV(1))(PC(20)) and eosinophil percentage in induced sputum were measured. RESULTS 31 subjects were former asthma subjects (FBA), 11 subjects were current asthma subjects (CBA) and 284 subjects had no history of asthma (non-BA). PC(20) and FEV(1)/FVC ratio were significantly lower in the FBA group than in the non-BA group (P < 0.01). Maximal mid-expiratory flow (MMF) was significantly lower in the FBA group than in the non-BA group (P < 0.05). Sputum eosinophil percentage was significantly increased in the FBA group compared with the non-BA group (P < 0.01). PC(20) was significantly lower in the CBA group than in the FBA and non-BA groups (P < 0.01). FEV(1), FEV(1)/FVC ratio and MMF were significantly lower in the CBA group than in the FBA group (P < 0.05, P < 0.05 and P < 0.05, respectively) and the non-BA group (P < 0.01, P < 0.01 and P < 0.05, respectively). Sputum eosinophils were significantly higher in the CBA group than in the FBA and non-BA groups (P < 0.01). CONCLUSIONS This study shows that subjects with long-term outgrown asthma continue to have airway eosinophilic inflammation, airway hyperresponsiveness and airway narrowing.


Respiratory investigation | 2015

Pleuroparenchymal fibroelastosis: Distinct pulmonary physiological features in nine patients

Satoshi Watanabe; Yuko Waseda; Hazuki Takato; Ryo Matsunuma; Takeshi Johkoh; Ryoko Egashira; Yoshinori Kawabata; Hiroko Ikeda; Masahide Yasui; Masaki Fujimura; Kazuo Kasahara

BACKGROUND Pleuroparenchymal fibroelastosis (PPFE) is a rare idiopathic interstitial pneumonia defined by pleural and subpleural parenchymal fibrosis predominantly in the upper lobes. Although the radiological and pathological characteristics of PPFE have become increasingly recognized, its pulmonary physiological features are not well understood. METHODS We reviewed nine patients with radiologically and histologically proven PPFE, and evaluated pulmonary physiological data. RESULTS Of the nine patients, six were male and three were female. The median age at presentation was 61 years. Common symptoms were dyspnea on exertion, weight loss, and nonproductive cough. Recurrent pneumothorax was found in eight patients and pneumonia in four. Median pulmonary function test results were as follows: forced vital capacity, 55.4% predicted; total lung capacity (TLC), 67.1% predicted; residual volume (RV), 102.3% predicted; and RV/TLC, 143.6% predicted. RV/TLC was increased without evidence of small airway disease according to clinico-radiologic-pathologic evaluation. The median partial pressure of oxygen in arterial blood and the alveolar-arterial gradient of oxygen were within normal limits, although there was a slightly elevated partial pressure of carbon dioxide in arterial blood (PaCO2). PPFE progressed in all patients despite treatment with pirfenidone, corticosteroids, and immunosuppressive agents. Seven patients died during the follow-up, five because of hypercapnic respiratory failure. CONCLUSIONS PPFE is characterized by severe mechanical restriction with high RV/TLC, causing increased PaCO2 and eventual hypercapnic respiratory failure. These physiological findings may be useful as an adjunct in the diagnosis of PPFE.


Allergology International | 2016

Severe pneumonitis after nivolumab treatment in a patient with melanoma

Satoshi Watanabe; Hideharu Kimura; Hazuki Takato; Yuko Waseda; Johsuke Hara; Takashi Sone; Miki Abo; Shintaro Maeda; Takashi Matsushita; Kazuo Kasahara

Nivolumab is an immune checkpoint inhibitor that binds to the Programmed death 1 (PD-1) receptor and blocks its interaction withPD-L1andPD-L2, thereby reversing tumor-inducedsuppression of tumor-specific T cells.1,2 Nivolumab is currently approved for the treatment of metastatic melanoma, squamous cell lung cancer, and renal cell cancer. Although generally well tolerated, nivolumab can induce immune-related pneumonitis. We herein describe a case of severe pneumonitis after nivolumab treatment for melanoma. A 73-year-old woman with metastatic melanoma (brain, lung) presented to our institution with fever, fatigue, and non-productive cough. Five months prior to presentation, she had begun treatment withnivolumab(2mg/kg, every threeweeks).After sixcyclesof treatment, one week prior to presentation, she developed fever, fatigue, and non-productive cough. Her past medical history was significant for thoracic aortic aneurysm status post stent graft. She was a nonsmoker and had no history of chronic lung disease. On examination, body temperature was 37.0 C, blood pressure was 121/75 mm Hg, heart rate was 82/min, and oxygen saturation on room air was 95%. Her physical examination was unremarkable. Laboratory tests demonstratedwhite blood cell count of 10,970/mLwith 85.6% neutrophils and 6.1% lymphocytes, C-reactive protein level of 14.3 mg/dL (normal <0.3 mg/dL), serum lactate dehydrogenase (LDH) level of 138 IU/L (normal, 119e229 IU/L), and Krebs von den Lungen-6 (KL6) level of 250 U/mL (normal <500 U/mL). Arterial blood gas analysis on room air showed pH of 7.479, PaCO2 of 37.6 mmHg and PaO2 of 61.0 mmHg. Chest radiography showed a right lung infiltrate and blunting of the right costophrenic angle. Chest computed tomography (CT) scan revealed a consolidation with air bronchograms, ground-glass attenuations, and patchy shadows, predominantly in the right lung. These abnormalities mainly involved the dependent lung regions. A right pleural effusion was also present. A metastatic lung tumor was found in the left lower lobe, but no abnormalities were observed around the tumor (Fig. 1). Although sputum culture didnot reveal anymicroorganisms, includingmycobacteria and fungi, she was initially diagnosed with bacterial pneumonia due to her symptoms and CT findings. Nivolumab was discontinued, and tazobactam/piperacillin (TAZ/PIPC) and levofloxacin (LVFX) antibiotics were initiated, but her symptoms did not improve. On hospital day 11, TAZ/PIPC was switched to meropenem (MEPM). However, she developed progressive dyspnea with severe hypoxemia, and the diffuse consolidation, ground-glass attenuations, and pleural effusions worsened on CT imaging, in a pattern suggestive of diffuse


European Journal of Radiology | 2016

Antisynthetase syndrome: Pulmonary computed tomography findings of adult patients with antibodies to aminoacyl-tRNA synthetases

Yuko Waseda; Takeshi Johkoh; Ryoko Egashira; Hiromitsu Sumikawa; Keigo Saeki; Satoshi Watanabe; Ryo Matsunuma; Hazuki Takato; Yukari Ichikawa; Yasuhito Hamaguchi; Akira Shiraki; Yoshinao Muro; Masahide Yasui; Helmut Prosch; Christian J. Herold; Kazuo Kasahara

OBJECTIVES To describe the pulmonary CT findings in patients with anti-ARS-antibody-positive interstitial lung disease (anti-ARS-ILD) METHODS: The CT findings of 64 patients with anti-ARS-ILD were retrospectively reviewed. The images were retrospectively reviewed independently by 2 chest radiologists, and the final decision on the CT findings was made by a third chest radiologist. RESULTS There were 16 male and 48 female patients, aged 54.2±13.4 years. Sixteen patients had anti Jo-1, 24 had anti-EJ, 9 had anti-PL-7, 7 had anti-PL-12, 5 had anti-KS, and 3 had anti-OJ antibodies. Overall, 63 patients (98.4%) had CT findings predominantly in the lower lobe; 61 patients (95.3%) showed peripheral opacities, and 47 patients (73.4%) showed peribronchovascular opacities. Ground-glass attenuation, consolidation, and reticulation showed similar distribution patterns. Regarding detailed CT findings, 89.1% of patients had lower volume loss, 76.6% had interlobular septal thickening, and 67.2% had thickening of bronchovascular bundles. The final radiologic diagnoses were as follows: inconsistent with usual interstitial pneumonia (UIP) in 63 patients (98.4%), which included nonspecific interstitial pneumonia (NSIP) in 35 patients (55.6%), organizing pneumonia (OP) in 4 patients (6.3%), and OP with fibrosis in 22 patients (34.9%). CONCLUSIONS The characteristic CT findings of patients with anti-ARS-ILD were areas of ground-glass attenuation and reticulation, predominantly distributed as lower and peribronchovascular lesions, which is compatible with NSIP. One-third of patients showed OP with fibrosis.


Allergology International | 2011

A case of microscopic polyangiitis following mycoplasma infection in a patient with MPO-ANCA positive pulmonary fibrosis.

Hazuki Takato; Masahide Yasui; Yuko Waseda; Nobuhiko Sakai; Takashi Wada; Masaki Fujimura

BACKGROUND Microscopic polyangiitis is a vasculitic disease that may result in a pulmonary renal syndrome. Anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis is strongly associated with infection. CASE SUMMARY We describe a case of microscopic polyangiitis that developed in a patient with MPO-ANCA positive pulmonary fibrosis following infection with mycoplasma. A renal biopsy was undertaken following the detection of microscopic hematuria during follow-up but no abnormal findings were evident. The MPO-ANCA titer increased following infection with mycoplasma pneumonia and a second renal biopsy demonstrated crescentic glomerulonephritis. The degree of pulmonary fibrosis was unaffected. DISCUSSION The present case suggests that the mycoplasma infection triggered the elevation of MPO-ANCA titer and provoked glomerulonephritis in a patient with MPO-ANCA positive IPF. This case indicates the importance of testing for MPO-ANCA at the time of initial diagnosis, performing urinalysis and examining the urine sediment during follow-up and being alert to the potential onset of vasculitis in cases of pulmonary fibrosis.


Bone Marrow Transplantation | 2015

Imatinib for bronchiolitis obliterans after allogeneic hematopoietic stem cell transplantation.

Satoshi Watanabe; Yuko Waseda; Hideharu Kimura; Hazuki Takato; Kinya Ohata; Yukio Kondo; Kazuo Kasahara; Shinji Nakao

Imatinib for bronchiolitis obliterans after allogeneic hematopoietic stem cell transplantation

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