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Dive into the research topics where Kazumasa Yasuda is active.

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Featured researches published by Kazumasa Yasuda.


Chest | 2008

Alterations in Smoking Habits Are Associated With Acute Eosinophilic Pneumonia

Hiroshi Uchiyama; Takafumi Suda; Yutaro Nakamura; Masahiro Shirai; Hitoshi Gemma; Toshihiro Shirai; Mikio Toyoshima; Shiro Imokawa; Kazumasa Yasuda; Masaaki Ida; Yutaka Nakano; Naoki Inui; Jun Sato; Hiroshi Hayakawa; Kingo Chida

BACKGROUND Acute eosinophilic pneumonia (AEP) is characterized by a febrile illness, diffuse pulmonary infiltrates, and pulmonary eosinophilia. The etiology of AEP remains unknown, but several studies have proposed a relationship between cigarette smoking and AEP. However, most studies showing this possibility are single-case reports, and cigarette smoke has not been fully validated as a causative agent of AEP in a large series of patients. The present study was conducted to clarify the etiologic role of cigarette smoking in AEP, with special reference to alterations in smoking habits. METHODS We took a detailed history of smoking habits before AEP onset in 33 patients with AEP, and performed a cigarette smoke provocation test. RESULTS Of our AEP patients, all but one (97%) were current smokers. Interestingly, 21 of these were new-onset smokers, and 2 had restarted smoking after a 1- to 2-year cessation of smoking. The duration between starting smoking and AEP onset was within 1 month (0.67 +/- 0.53 months). Additionally, six of the remaining smokers had increased the quantity of cigarettes smoked daily, fourfold to fivefold, mostly within the month before AEP onset (0.81 +/- 0.58 months). Only three smokers had not changed their smoking habits before AEP onset. Cigarette smoke provocation tests revealed positive results in all nine patients tested. CONCLUSION These data suggest that recent alterations in smoking habits, not only beginning to smoke, but also restarting to smoke and increasing daily smoking doses, are associated with the development of AEP.


Respirology | 2009

Real‐time PCR is more specific than conventional PCR for induced sputum diagnosis of Pneumocystis pneumonia in immunocompromised patients without HIV infection

Tomoyuki Fujisawa; Takafumi Suda; Hiroyuki Matsuda; Naoki Inui; Yutaro Nakamura; Jun Sato; Mikio Toyoshima; Yutaka Nakano; Kazumasa Yasuda; Hitoshi Gemma; Hiroshi Hayakawa; Kingo Chida

Background and objective:  The diagnosis of Pneumocystis pneumonia (PCP) is based on microscopic examination of respiratory specimens. PCP patients without AIDS have a lower burden of P. jiroveci than those with AIDS, which leads to difficulty in detecting the organisms. Although conventional PCR (c‐PCR) has been used to detect the DNA, it is frequently positive in patients with colonization. Real‐time PCR (r‐PCR), a method to detect the DNA quantitatively, might be helpful in distinguishing between infection and colonization. We investigated the utility of real‐time PCR in the diagnosis of PCP in non‐AIDS patients.


PLOS ONE | 2014

Prognostic Factors for Myositis-Associated Interstitial Lung Disease

Tomoyuki Fujisawa; Hironao Hozumi; Masato Kono; Noriyuki Enomoto; Dai Hashimoto; Yutaro Nakamura; Naoki Inui; Koshi Yokomura; Naoki Koshimizu; Mikio Toyoshima; Toshihiro Shirai; Kazumasa Yasuda; Hiroshi Hayakawa; Takafumi Suda

Background Interstitial lung disease (ILD) is a common manifestation of polymyositis (PM), dermatomyositis (DM), and clinically amyopathic dermatomyositis (CADM); however, little is known about the factors influencing the prognosis for PM/DM/CADM-associated ILD. (PM/DM/CADM-ILD). The aim of the present study is to assess prognostic factors for PM/DM/CADM-ILD. Methods The clinical features and survival of 114 consecutive patients diagnosed with PM/DM/CADM-ILD (39 men and 75 women; median age, 56 years) were analyzed retrospectively. Results The study group included 30 PM-associated ILD, 41 DM-associated ILD, and 43 CADM-associated ILD cases. The clinical presentation of ILD was acute/subacute form in 59 patients (51.8%) and chronic form in 55 patients (48.2%). The major pulmonary symptoms were dyspnea, cough, and fever. High-resolution computed tomography frequently revealed ground-glass opacities, traction bronchiectasis, and consolidation. Most of the patients were treated with corticosteroids or corticosteroids in combination with immunosuppressive agents. The all-cause mortality was 27.2%. Acute/subacute form, % forced vital capacity (FVC), age, % of neutrophils in bronchoalveolar lavage (BAL) fluid, and a diagnosis of CADM (vs. PM) were significantly associated with poor outcome in univariate Cox proportional hazards models. Multivariate Cox proportional hazards analysis validated acute/subacute ILD, %FVC, age, and diagnosis of CADM (vs. PM) as significant predictors of overall mortality. Patients with acute/subacute ILD had a much lower survival rate than those with the chronic form (p<0.001). Patients with CADM-ILD had a lower survival rate than those with PM-ILD (p = 0.034). Conclusions Acute/subacute form, older age, lower level of FVC and diagnosis of CADM predict poor outcome in PM/DM/CADM-ILD.


Respiratory Medicine | 2012

Rheumatoid lung disease: Prognostic analysis of 54 biopsy-proven cases

Yutaro Nakamura; Takafumi Suda; Yusuke Kaida; Masato Kono; Hironao Hozumi; Dai Hashimoto; Noriyuki Enomoto; Tomoyuki Fujisawa; Naoki Inui; Shiro Imokawa; Kazumasa Yasuda; Toshihiro Shirai; Hideki Suganuma; Satoru Morita; Hiroshi Hayakawa; Yasuo Takehara; Thomas V. Colby; Kingo Chida

OBJECTIVE To investigate the prognostic significance of histopathological characteristics in patients with biopsy-proven rheumatoid lung disease (RLD). MATERIALS AND METHODS Retrospective analysis was conducted on samples from 54 RLD patients who underwent surgical lung biopsies (SLBs) at Hamamatsu University Hospital and affiliated hospitals between 1980 and 2009. The overall survival rate, the spectrum of histopathological diagnosis and their associated prognostic significance were investigated. RESULTS The study group consisted of 30 men and 24 women with a median age of 60.3 years. Histopathological analysis revealed the following: usual interstitial pneumonia (UIP), 15 cases; nonspecific interstitial pneumonia/fibrosis, 16 cases; organizing pneumonia, 4 cases; unclassifiable, 2 cases; desquamative interstitial pneumonia, 1 case; and bronchiolar disease, 16 cases. In survival outcome, 10 yr survival rate was 76.6%. Patients with UIP had significantly worse prognosis than those with non-UIP (RLD cases except those with UIP) (p = 0.0452). CONCLUSION RLD includes several histopathological groups. Patients with UIP have worse survival than those with other types of RLD. Histopathological diagnosis may have a major impact on prognostication in patients with RLD.


Respiratory Medicine | 2010

Distinct prognosis of idiopathic nonspecific interstitial pneumonia (NSIP) fulfilling criteria for undifferentiated connective tissue disease (UCTD)

Takafumi Suda; Masato Kono; Yutaro Nakamura; Noriyuki Enomoto; Yusuke Kaida; Tomoyuki Fujisawa; Shiro Imokawa; Kazumasa Yasuda; Hideo Hashizume; Koushi Yokomura; Mikio Toyoshima; Naoki Koshimizu; Hideki Suganuma; Toshihiro Shirai; Dai Hashimoto; Naoki Inui; Thomas V. Colby; Kingo Chida

BACKGROUND Although idiopathic nonspecific interstitial pneumonia (NSIP) was initially identified as a provisional diagnosis, the 2008 American Thoracic Society Project concluded that idiopathic NSIP is a distinct form of idiopathic interstitial pneumonia. However, an association between idiopathic NSIP and autoimmune diseases still attracts interest. In this context, a recent study proposed an intriguing concept that idiopathic NSIP is the pulmonary manifestation of undifferentiated connective tissue disease (UCTD). However, this has not been confirmed in a large number of patients with idiopathic NSIP. The present study was conducted to investigate the proportion and characteristics of patients with idiopathic NSIP who meet the criteria for UCTD. METHODS We reviewed 47 consecutive patients with idiopathic NSIP and examined whether they met prespecified criteria for UCTD. Furthermore, we compared the clinical characteristics between patients fulfilling the UCTD criteria (UCTD-NSIP) and those not meeting them (Non-UCTD-NSIP). RESULTS Of 47 patients with idiopathic NSIP, 22 (47%) met the UCTD criteria. Common symptoms associated with connective tissue diseases (CTDs) were skin change (50%) and Raynauds phenomenon (41%) in UCTD-NSIP. UCTD-NSIP showed a female predominance and significantly higher percentages of lymphocytes with a lower CD4/CD8 ratio in bronchoalveolar lavage than Non-UCTD-NSIP. Interestingly, UCTD-NSIP had a significantly better survival than Non-UCTD-NSIP. CONCLUSIONS Idiopathic NSIP included subjects who fulfilled the UCTD criteria, and these subjects had different clinical characteristics with significantly better outcome than those who did not meet the criteria. These data suggest that a part, but not all, of patients with idiopathic NSIP show CTD-like features with a distinct prognosis.


European Respiratory Journal | 2008

Mycobacterium avium complex disease: prognostic implication of high-resolution computed tomography findings

Shigeki Kuroishi; Yutaro Nakamura; Hiroshi Hayakawa; Masahiro Shirai; Yasukatsu Nakano; Kazumasa Yasuda; Takafumi Suda; Hirotoshi Nakamura; Kingo Chida

To evaluate the prognostic implications of computed tomography (CT) findings in assessing responses to treatment in Mycobacterium avium complex (MAC) pulmonary disease without underlying lung disease, high-resolution (HR)CT findings were correlated based on the results of sputum conversion after anti-MAC therapy. A total of 59 patients underwent HRCT before treatment and the therapeutic efficacy was evaluated by the results of sputum conversion. Atelectasis, cavities and pleural thickening on HRCT were significantly more frequent and extensive among patients in the sputum nonconverted group than among those in the converted group. Furthermore, bronchiectasis was also significantly more extensive among patients in the nonconverted group, even though there was no significant difference in frequency between these two groups. These results suggest that high-resolution computed tomography findings are good predictors of response to treatment in Mycobacterium avium complex pulmonary disease.


Annals of the American Thoracic Society | 2014

Efficacy of Clarithromycin and Ethambutol for Mycobacterium avium Complex Pulmonary Disease. A Preliminary Study

Seiichi Miwa; Masahiro Shirai; Mikio Toyoshima; Toshihiro Shirai; Kazumasa Yasuda; Koshi Yokomura; Takashi Yamada; Masafumi Masuda; Naoki Inui; Kingo Chida; Takafumi Suda; Hiroshi Hayakawa

RATIONALE Patients with Mycobacterium avium complex pulmonary disease are frequently administered a combination of clarithromycin, ethambutol, and rifampicin. However, rifampicin is known to reduce the serum levels of clarithromycin. It remains unclear whether a reduction in clarithromycin serum levels influences the clinical outcome of the Mycobacterium avium complex pulmonary disease treatment regimen. OBJECTIVES To compare a three-drug regimen (clarithromycin, ethambutol, and rifampicin) to a two-drug regimen (clarithromycin and ethambutol) for the treatment of Mycobacterium avium lung disease. METHODS In a preliminary open-label study, we randomly assigned newly diagnosed, but as-yet untreated, patients with disease caused by Mycobacterium avium complex without HIV infection to either the three-drug or the two-drug regimen for 12 months. The primary endpoint was the conversion of sputum cultures to negative after 12 months of treatment. Patient data were analyzed using the intention-to-treat method. MEASUREMENTS AND MAIN RESULTS Of 119 eligible patients, 59 were assigned to the three-drug regimen and 60 to the two-drug regimen. The rate of sputum culture conversion was 40.6% with the three-drug regimen and 55.0% with the two-drug regimen (difference, -14.4% [95% confidence interval, -32.1 to 3.4]). The incidence of adverse events leading to the discontinuation of treatment was 37.2 and 26.6% for the three-drug and the two-drug regimens, respectively. CONCLUSIONS This preliminary study suggests that treatment with clarithromycin and ethambutol is not inferior to treatment with clarithromycin, ethambutol, and rifampicin for Mycobacterium avium complex lung disease. Our findings justify a larger clinical trial to compare long-term clinical outcomes for the two treatment regimens. Clinical trial registered with http://www.umin.ac.jp/english/ (UMIN000002819).


Journal of the American Geriatrics Society | 2006

A Validation and Potential Modification of the Pneumonia Severity Index in Elderly Patients with Community-Acquired Pneumonia

Tateaki Naito; Takafumi Suda; Kazumasa Yasuda; Takashi Yamada; Akihito Todate; Tomoyoshi Tsuchiya; Jun Sato; Kingo Chida; Hirotoshi Nakamura

OBJECTIVES: To evaluate the discriminatory power of the Pneumonia Severity Index (PSI) in elderly patients with community‐acquired pneumonia (CAP) and to improve its performance.


Lung Cancer | 2014

Aprepitant in patients with advanced non-small-cell lung cancer receiving carboplatin-based chemotherapy

Yasuhiro Ito; Masato Karayama; Naoki Inui; Shigeki Kuroishi; Hideki Nakano; Yutaro Nakamura; Koshi Yokomura; Mikio Toyoshima; Toshihiro Shirai; Masafumi Masuda; Takashi Yamada; Kazumasa Yasuda; Hiroshi Hayakawa; Takafumi Suda; Kingo Chida

OBJECTIVES Chemotherapy-induced nausea and vomiting (CINV) is an unanswered problem in cancer therapy. We evaluated the efficacy and safety of triple antiemetic therapy with aprepitant, a 5-hydroxytryptamine-3 (5-HT(3)) receptor antagonist, and dexamethasone in patients with advanced non-small-cell lung cancer (NSCLC) who received carboplatin-based first-line chemotherapy. METHODS Chemotherapy-naïve patients with NSCLC were enrolled in this randomized phase-II study. Patients were randomized to standard antiemetic therapy with a 5-HT(3) receptor antagonist and dexamethasone, and aprepitant add-on triple antiemetic therapy. The primary endpoint was the complete response rate (no vomiting and no rescue therapy) during the 120 h post-chemotherapy. RESULTS A total of 134 patients were assigned randomly to the aprepitant group or the control group. The aprepitant group and the control group showed an overall complete response rate of 80.3% (95% confidence interval (CI), 69.2-88.1%) and 67.2% (95% CI, 55.3-77.2%; odds ratio (OR), 0.50; 95% CI, 0.22-1.10; p = 0.085), respectively. Among patients taking carboplatin and pemetrexed, adding aprepitant significantly improved the complete response rate in the overall phase (83.8% in the aprepitant group and 56.8% in the control group; OR, 0.26; 95% CI, 0.08-0.70; p < 0.01) and the delayed phase (86.5% in the aprepitant group and 59.1% in the control group; OR, 0.23; 95% CI, 0.07-0.65; p < 0.01). CONCLUSION Carboplatin-based chemotherapy has considerable emetic potential. Triple antiemetic therapy with aprepitant, a 5-HT(3) receptor antagonist, and dexamethasone improved the control of CINV prevention in patients receiving carboplatin and pemetrexed chemotherapy.


Japanese Journal of Clinical Oncology | 2011

Phase II Study of Erlotinib as Third-line Monotherapy in Patients with Advanced Non-small-cell Lung Cancer without Epidermal Growth Factor Receptor Mutations

Shun Matsuura; Naoki Inui; Yuichi Ozawa; Yutaro Nakamura; Mikio Toyoshima; Kazumasa Yasuda; Takashi Yamada; Toshihiro Shirai; Hideki Suganuma; Koji Yokomura; Takafumi Suda; Kingo Chida

OBJECTIVE There are few standard therapeutic options beyond second-line treatment. We aimed to evaluate the efficacy and safety of erlotinib monotherapy as third-line chemotherapy in patients with advanced non-small-cell lung cancer without epidermal growth factor receptor mutations. METHODS In this phase II trial, patients who did not have epidermal growth factor receptor mutations and who had previously received two cytotoxic chemotherapy regimens containing platinum were treated with erlotinib (150 mg, per os) until disease progression or unacceptable toxicity. RESULTS Twenty patients were eligible for the assessment of efficacy and safety. Three cases showed a partial response, and eight cases showed stable disease with an overall response rate of 15.0% (95% confidence interval: 5.2-36.0%) and a disease control rate of 55.0% (95% confidence interval: 34.2-74.2%). Median progression-free survival and overall survival time were 2.1 and 6.7 months, respectively. Although dose reduction was required in one patient because of skin toxicity, grade 3/4 toxicity or pulmonary disease was not observed. CONCLUSIONS Erlotinib as third-line therapy showed an acceptable response rate, survival time and toxicity. It could be a potential third-line therapy for patients without epidermal growth factor receptor mutations.

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