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Dive into the research topics where Keisaku Fujimoto is active.

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Featured researches published by Keisaku Fujimoto.


European Respiratory Journal | 2005

Airway inflammation during stable and acutely exacerbated chronic obstructive pulmonary disease

Keisaku Fujimoto; Masanori Yasuo; Kazutoshi Urushibata; Masayuki Hanaoka; Koizumi T; Keishi Kubo

The aim of this study was to clarify the mechanism of increased airway inflammation during an acute exacerbation. A total of 68 chronic obstructive pulmonary disease patients in a stable phase were enrolled and followed-up for 2–3 yrs. Inflammatory cells were analysed, and interleukin (IL)-8, neutrophil elastase, eotaxin, tryptase and RANTES (regulated on activation, normal T-cell expressed and secreted) were measured in sputum, both in a stable phase and during acute exacerbation. Out of 68 patients, 30 (unstable group) developed an acute exacerbation and expectorated adequate sputum during exacerbation. Thirty-two patients (stable group) did not develop any exacerbation for 2–3 yrs. The number of neutrophils, lymphocytes and eosinophils, and the levels of IL-8, eosinophil cationic protein (ECP), eotaxin and tryptase in sputum obtained from patients in both groups during the stable phase were significantly higher than those from healthy nonsmokers. There were no significant differences in cell analysis and biomarkers between the two groups, but patients in the unstable group showed more severe airflow limitation. In the unstable group, total cells, lymphocytes, neutrophils and eosinophils, and IL-8, neutrophil elastase, ECP and RANTES levels were significantly increased during an exacerbation from values in a stable phase. These findings suggest that exacerbation of chronic obstructive pulmonary disease may associate with additional increases in airway inflammation mediated by neutrophils, lymphocytes, eosinophils, interleukin-8 and RANTES.


Circulation | 2002

Positive Association of the Endothelial Nitric Oxide Synthase Gene Polymorphisms With High-Altitude Pulmonary Edema

Yunden Droma; Masayuki Hanaoka; Masao Ota; Yoshihiko Katsuyama; Tomonobu Koizumi; Keisaku Fujimoto; Toshio Kobayashi; Keishi Kubo

Background—A defect of nitric oxide (NO) synthesis in the lung of high-altitude pulmonary edema (HAPE) has been suggested to contribute to its exaggerated pulmonary hypertension. Several polymorphisms have been identified in the gene encoding endothelial nitric oxide synthase (eNOS), which is a key enzyme responsible for NO synthesis, some of which were reported to be associated with vascular disorders. Methods and Results—We studied 41 HAPE-susceptible subjects (HAPE-s) and 51 healthy climbers (control group) in a Japanese population. We examined 2 polymorphisms of the eNOS gene, including the Glu298Asp variant and 27-base pair (bp) variable numbers of tandem repeats using polymerase chain reaction followed by restriction fragment length polymorphism. The Asp allelic frequency of the Glu298Asp variant was 25.6% in the HAPE-s and 9.8% in the controls, which was significantly different between the two groups (P =0.0044). The eNOS4a allelic frequency of 27-bp variable numbers of tandem repeats was 23.2% in the HAPE-s, significantly higher than that of 6.9% in the controls (P =0.0016). In HAPE-s group, 11 of 41 (26.8%) subjects possessed simultaneously both of the two significant alleles, but among the controls, none did, which showed a high statistical difference between the two groups (P =0.000059). Conclusions—Both polymorphisms of the eNOS gene were significantly associated with HAPE. A genetic background may underlie the impaired NO synthesis in the pulmonary circulation of HAPE-s. These polymorphisms could be genetic markers for predicting the susceptibility to HAPE.


European Respiratory Journal | 2003

Evaluation of airway wall thickness and air trapping by HRCT in asymptomatic asthma

H. Gono; Keisaku Fujimoto; Satoshi Kawakami; Keishi Kubo

The aim of this study was to examine the relationship between the structural changes in large and small airways in asymptomatic asthmatics quantified by high-resolution computed tomography (HRCT) and airflow obstruction. The bronchial wall thickness at the trunk of the apical bronchus (B1) of the right upper lobe was used for assessment of the large airways. Air trapping, evaluated by the ratio of the average CT‐determined values for the bilateral upper and lower lung segments at full expiration to that at full inspiration (E/I ratio), was used for assessment of the small airways. Measurements were obtained with a helical HRCT in 24 asymptomatic asthmatics followed by optimal treatment with inhaled and/or oral corticosteroids for >6 months. Prior (20–30 min) to the HRCT examination, all patients were given an inhaled bronchodilator. The ratio of airway wall thickness to outer diameter (T/D) and the percentage wall area (WA%) at the B1 bronchus and the E/I ratio were significantly greater for the 14 asthmatics with deficient reversible airflow obstruction (forced expiratory volume in one second (FEV1) <80% prediced or FEV1/forced vital capacity <70% after bronchodilator inhalation) than for the 10 asthmatics with normal spirometry and seven normal subjects. T/D, WA%, and E/I ratio showed significant negative correlations with FEV1 % pred after bronchodilator inhalation. The E/I ratio also showed significant positive correlations with T/D, WA%, and residual volume/total lung capacity. These findings suggest that, in spite of optimal treatment, structural changes in both large and small airways may simultaneously occur in asthmatics with deficient reversible airflow obstruction.


Respiration Physiology | 1998

Inflammatory cytokines in BAL fluid and pulmonary hemodynamics in high-altitude pulmonary edema.

Keishi Kubo; Masayuki Hanaoka; Toshihide Hayano; Takashige Miyahara; Tsutomu Hachiya; Muneharu Hayasaka; Tomonobu Koizumi; Keisaku Fujimoto; Toshio Kobayashi; Takayuki Honda

To evaluate the pathogenesis of high-altitude pulmonary edema (HAPE), we performed bronchoalveolar lavage (BAL) and pulmonary hemodynamic studies in seven patients with HAPE at its early stage. We measured cell counts, biochemical contents, and concentrations of pro-inflammatory cytokines including interleukin (IL)-1, IL-6, IL-8 and tumor necrosis factor (TNF)-alpha and of anti-inflammatory cytokines including IL-1 receptor antagonist (ra) and IL-10 in the BAL fluid (BALF). All patients showed increased counts for total cells, alveolar macrophages, neutrophils and lymphocytes, and markedly elevated concentrations of proteins, lactate dehydrogenase, IL-1beta, IL-6, IL-8, TNF-alpha and IL-1ra. The levels of IL-1alpha and IL-10 were not increased. Patients also showed pulmonary hypertension with normal wedge pressure. Both the driving pressure obtained as pulmonary arterial pressure minus wedge pressure and the PaO2 under room air were significantly correlated with the concentrations of IL-6 and TNF-alpha in the BALF. These findings suggest that the inflammatory cytokines play a role at the early stage of HAPE and might be related to pulmonary hypertension.


Respirology | 2010

Clinical characteristics of combined pulmonary fibrosis and emphysema

Yoshiaki Kitaguchi; Keisaku Fujimoto; Masayuki Hanaoka; Satoshi Kawakami; Takayuki Honda; Keishi Kubo

Background and objective:  Patients with combined pulmonary fibrosis and emphysema (CPFE) are sometimes seen, and we speculate that these patients have some different clinical characteristics from COPD patients. This study clarifies the clinical characteristics of CPFE patients.


Respirology | 2006

Clinical analysis of chronic obstructive pulmonary disease phenotypes classified using high-resolution computed tomography

Keisaku Fujimoto; Yoshiaki Kitaguchi; Keishi Kubo; Takayuki Honda

Objective and background:  The present study was performed to clarify the clinical characteristics of patients with COPD classified into phenotypes according to the dominancy of emphysema and the presence of bronchial wall thickening (BWT) evaluated by chest high‐resolution CT.


International Journal of Chronic Obstructive Pulmonary Disease | 2012

Sputum eosinophilia can predict responsiveness to inhaled corticosteroid treatment in patients with overlap syndrome of COPD and asthma

Yoshiaki Kitaguchi; Yoshimichi Komatsu; Keisaku Fujimoto; Masayuki Hanaoka; Keishi Kubo

Background Chronic obstructive pulmonary disease (COPD) and asthma may overlap and converge in older people (overlap syndrome). It was hypothesized that patients with overlap syndrome may have different clinical characteristics such as sputum eosinophilia, and better responsiveness to treatment with inhaled corticosteroid (ICS). Methods Sixty-three patients with stable COPD (forced expiratory volume in 1 second [FEV1] ≤80%) underwent pulmonary function tests, including reversibility of airflow limitation, arterial blood gas analysis, analysis of inflammatory cells in induced sputum, and chest high-resolution computed tomography. The inclusion criteria for COPD patients with asthmatic symptoms included having asthmatic symptoms such as episodic breathlessness, wheezing, cough, and chest tightness worsening at night or in the early morning (COPD with asthma group). The clinical features of COPD patients with asthmatic symptoms were compared with those of COPD patients without asthmatic symptoms (COPD without asthma group). Results The increases in FEV1 in response to treatment with ICS were significantly higher in the COPD with asthma group. The peripheral eosinophil counts and sputum eosinophil counts were significantly higher. The prevalence of patients with bronchial wall thickening on chest high-resolution computed tomography was significantly higher. A significant correlation was observed between the increases in FEV1 in response to treatment with ICS and sputum eosinophil counts, and between the increases in FEV1 in response to treatment with ICS and the grade of bronchial wall thickening. Receiver operating characteristic curve analysis revealed 82.4% sensitivity and 84.8% specificity of sputum eosinophil count for detecting COPD with asthma, using 2.5% as the cutoff value. Conclusion COPD patients with asthmatic symptoms had some clinical features. ICS should be considered earlier as a potential treatment in such patients. High sputum eosinophil counts and bronchial wall thickening on chest high-resolution computed tomography might therefore be a good predictor of response to ICS.


Thorax | 1996

Cytokines in bronchoalveolar lavage fluid in patients with high altitude pulmonary oedema at moderate altitude in Japan.

Keishi Kubo; Masayuki Hanaoka; Shinji Yamaguchi; Toshihide Hayano; Muneharu Hayasaka; Koizumi T; Keisaku Fujimoto; Toshio Kobayashi; Takayuki Honda

BACKGROUND: The precise mechanism of high altitude pulmonary oedema (HAPE) remains unclear. The purpose of this study was to evaluate the role of cytokines and P-selectin in the development of HAPE which occurred at moderate altitude in Japan. METHODS: The following cellular and biochemical markers and chemotactic cytokines were measured in the bronchoalveolar (BAL) fluid from four patients with HAPE at 2857-3180 m in the Japanese Alps: total proteins, albumin, lactate dehydrogenase (LDH), and interleukin (IL)-1 alpha, IL-1 beta, IL-1 receptor antagonist (ra), IL-6, IL-8, IL-10, tumour necrosis factor (TNF)-alpha, and the soluble form of P-selectin. RESULTS: At admission there were significant increases in the levels of total cells, especially macrophages and neutrophils, total protein, albumin and LDH when compared with 13 healthy individuals. Furthermore, the levels of IL-1 beta, IL-6, IL-8, and TNF-alpha were also considerably increased but returned quickly to the normal ranges or were not detected after recovery. The levels of IL-1 alpha, IL-10, and P-selectin did not change. CONCLUSIONS: These results suggest that an inflammatory process almost identical with acute respiratory distress syndrome (ARDS) may occur in HAPE, but that these changes are transient and are not associated with any increase in P-selectin levels in the BAL fluid.


American Journal of Clinical Oncology | 2002

Chemotherapy for advanced thymic carcinoma: clinical response to cisplatin, doxorubicin, vincristine, and cyclophosphamide (ADOC chemotherapy).

Thomonobu Koizumi; Yasuki Takabayashi; Satoshi Yamagishi; Kenji Tsushima; Akemi Takamizawa; Akihiro Tsukadaira; Hiroshi Yamamoto; Yoshitaka Yamazaki; Shinji Yamaguchi; Keisaku Fujimoto; Keishi Kubo; Yoshiki Hirose; Jirou Hirayama; Hisanori Saegusa

The role of systemic chemotherapy and optimal regimen in thymic carcinoma remains uncertain. We evaluated the clinical responsiveness of ADOC (cisplatin, doxorubicin, vincristine, and cyclophosphamide) chemotherapy for advanced thymic carcinoma that have distant metastatic or unresectable lesions. From 1996 to 2000, we treated eight cases of thymic carcinoma. According to the classification by Masaoka et al., the clinical stage in one case was IVa, whereas the others were IVb. Histologic subtypes were as follows: four cases were squamous cell carcinoma, two cases were undifferentiated, and two were small-cell carcinoma. All patients received 50 mg/m2 of cisplatin and 40 mg/m2 of doxorubicin intravenously on day 1, 0.6 mg/m2 of vincristine intravenously on day 3, and 700 mg/m2 of cyclophosphamide intravenously on day 4, ADOC regimen, respectively, at 3- to 4-week intervals. Six patients obtained a partial response after ADOC chemotherapy and the overall clinical response rate was 75%. There were no life-threatening side effects noted. Cisplatin plus VP-16 chemotherapy (PVP) was performed in three cases before the ADOC regimen, but PVP chemotherapy did not show beneficial effects in two patients. Median survival time was 19 months. ADOC chemotherapy appears to have significant activity against thymic carcinoma.


Respirology | 2006

Hypoxia-sensitive molecules may modulate the development of atherosclerosis in sleep apnoea syndrome

Motonori Hayashi; Keisaku Fujimoto; Kazuhisa Urushibata; Akemi Takamizawa; Osamu Kinoshita; Keishi Kubo

Objectives:  Obstructive sleep apnoea hypopnoea syndrome (OSAHS) is associated with increased morbidity and mortality due to cardiovascular disease. In order to examine the association between OSAHS and cardiovascular disease, this study measured hypoxia‐inducible and atherosclerosis‐associated molecules in the peripheral blood.

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