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Michiaki Mishima

Publications and source records attributed to Michiaki Mishima.

At least 19 recordsLinked to original sources
PubMed2007

Prevalence and clinical manifestations of gastro-oesophageal reflux-associated chronic cough in the Japanese population.

Gastro-oesophageal reflux (GOR) is one of the most common causes of chronic cough in Western countries, responsible for 10 to 40% of cases. In Japan, however, GOR-associated chronic cough (GOR-CC) has been rarely reported and its clinical manifestation including frequency of concomitant reflux laryngitis is poorly known. We have analyzed prevalence and clinical characteristics of patients who were diagnosed as having GOR-CC among adult patients with chronic cough (>or= 8 weeks) who visited our asthma and cough clinic over a period of 19 months. Diagnosis of GOR-CC was based on the response of coughing to a proton-pump inhibitor (lansoprazole) and/or positive results of 24 h ambulatory esophageal pH monitoring. Laryngeal involvement was based on symptoms or objective diagnosis by specialists.GOR-associated chronic cough was diagnosed in 7.1% (8 of 112) of chronic cough patients. In addition to the demographic data which were consistent with the characteristics of patients with GOR-CC in the Western populations, including gender (6 females), age (mean +/- SE, 56.9 +/- 5.8 years), duration of cough (9.9 +/- 3.3 months), lack of gastrointestinal symptoms (3 of 8) and complication with other causes of cough (5 of 8), we found the standard range of body mass index (23.9 +/- 1.5 kg/m2) and high incidence of concomitant reflux laryngitis (5 of 8) in the present 8 patients. Among 4 patients who could stop treatment with temporal resolution of cough, cough recurred in 3 patients, 1 week to 8 months after the discontinuation. In conclusion, GOR-CC is a less frequent cause of chronic cough in Japan than in Western countries. Signs or symptoms of laryngitis may be important as clues to suspicion of GOR-CC.

Journal Article↗
PubMed2006

Retrospective study of 30 cases of Legionella pneumonia in the Kansai region.

Thirty Legionella pneumonia cases were clinically investigated retrospectively from 1999 to 2005 at the Respiratory Medicine Department of Kyoto University and affiliated hospitals. Twenty-eight cases were sporadic and two cases were part of an outbreak. The patients consisted of 28 men and 2 women, with a mean age of 58.8 years (range 25-87). Nineteen cases were smokers and 19 had some underlying disease. The mean period from the disease occurrence to presenting at a hospital was 4.8 days (range 1-15). The mean period from presenting at hospital to Legionella pneumonia diagnosis was 4.6 days (range 0-22). Urinary antigen detection tests for Legionella pneumophilla were performed for 25 cases, and resulted in the diagnosis of 22 cases. Other diagnostic tests with positive findings were culture (buffered charcoal-yeast extract agar, BCYE), the polymerase chain reaction (PCR) test, and serological diagnosis (enzyme immunoassay and microagglutination test). Legionella species diagnosis was obtained by culture and serology for 13 cases: 10 cases had Legionella pneumophila serogroup 1, 2 cases had Legionella pneumophila serogroup 6, and 1 case had Legionella longbeachea. Fluoloquinolones (Fq) are most often used for therapy, especially in recent cases, and were predominantly the chosen treatment (70%). Death due to Legionella pneumonia occurred in 4 cases: 3 cases had severe underlying diseases, and 1 case took 18 days to diagnose (doctors' delay). To detect the majority of Legionella pneumonia cases, a combination of diagnostic examinations is still needed. Regarding the management of community-acquired pneumonia, both the cost and the indication of diagnostic examinations for Legionella infection should be considered simultaneously.

Adult↗
PubMed2006

All-trans-retinoic acid prevents radiation- or bleomycin-induced pulmonary fibrosis.

RATIONALE: Although radiotherapy is effective in treating lung cancers, resultant pulmonary injury is the main obstacle. Pulmonary fibrosis is characterized by progressive worsening in pulmonary function leading to high incidence of death. Currently, however, there has been little progress in effective preventive and therapeutic strategies. OBJECTIVES: Previously, we reported that all-trans-retinoic acid (ATRA) reduced both irradiation-induced interleukin (IL)-6 production in lung fibroblasts and IL-6-dependent cell growth, and also directly inhibited the proliferation of lung fibroblasts after irradiation. In this study, we examined the preventive effect of ATRA on the progression of lung fibrosis both in irradiated and bleomycin-treated mice. MEASUREMENTS: We performed histologic examinations and quantitative measurements of IL-6, transforming growth factor (TGF)-beta(1), and collagen type Ialpha1 (COL1A1) in irradiated and bleomycin- treated mouse lung tissues with or without the administration of ATRA. RESULTS: Lethal irradiation effect was reduced by intraperitoneal administration of ATRA, and the overall survival rate at 16 wk was 30.0% without ATRA (n = 11), whereas it was 81.8% (n = 10) in the treatment group (p = 0.04). In vitro studies disclosed that the administration of ATRA reduced (1) irradiation-induced production of IL-6, TGF-beta(1), and collagen from IMR90 cells, and (2) IL-6-dependent proliferation and TGF-beta(1)-dependent transdifferentiation of the cells, which could be the mechanism underlying the preventive effect of ATRA on lung fibrosis. Furthermore, ATRA ameliorated bleomycin-induced fibrosis in mouse lung tissues. CONCLUSIONS: These data may provide a rationale to explore clinical use of ATRA for the prevention of radiation-induced lung fibrosis and other pathologic conditions involving pulmonary fibrosis.

Animals↗
PubMed2006

Role of small airways in asthma: investigation using high-resolution computed tomography.

BACKGROUND: Small airways may have an important role in asthma but are more difficult to assess pathologically than central airways. Computed tomographic indices of lung density are assumed to reflect air trapping and may be a useful noninvasive measure of small airways disease, but their pathophysiological relevance remains undetermined. OBJECTIVE: To evaluate lung density on high-resolution computed tomography and examine its correlations with clinical and physiologic variables in 29 patients with stable asthma. METHODS: Both lungs were scanned at full-inspiratory and full-expiratory phases to quantify percentage of lung field occupied by low attenuation area (LAA%; < -960 Hounsfield units) and mean lung density. Asthma severity, pulmonary function, methacholine airway sensitivity and reactivity, and sputum eosinophil counts were evaluated. RESULTS: The mean lung density increased and LAA% decreased in all patients at expiratory phase compared with inspiratory phase. The inspiratory density indices and expiratory mean lung density correlated only with FEV(1)/forced vital capacity (FVC). Expiratory LAA% correlated more strongly than other variables with FEV(1)/FVC and with indices of peripheral airflow obstruction. Expiratory/inspiratory ratios of LAA% and mean lung density correlated, the former more strongly, with disease severity, residual volume/total lung capacity, and airway sensitivity, as well as with indices of global (FEV(1) and FEV(1)/FVC) and peripheral airflow obstruction. CONCLUSION: Expiratory/inspiratory high-resolution computed tomography is useful for assessing small airways disease in asthma. Small airways involvement is associated with airflow obstruction, airway hypersensitivity, and more severe disease. CLINICAL IMPLICATIONS: Small airways are an important therapeutic target in asthma.

Adult↗
PubMed2006

Longitudinal deteriorations in patient reported outcomes in patients with COPD.

Goals of effective management of patients with chronic obstructive pulmonary disease (COPD) include relieving their symptoms and improving their health status. We examined how such patient reported outcomes would change longitudinally in comparison to physiological outcomes in COPD. One hundred thirty-seven male outpatients with stable COPD were recruited for the study. The subjects health status was evaluated using the St. George's Respiratory Questionnaire (SGRQ) and the Chronic Respiratory Disease Questionnaire (CRQ). Their dyspnoea using the modified Medical Research Council (MRC) scale and their psychological status using the Hospital Anxiety and Depression Scale (HADS) were assessed upon entry and every 6 months thereafter over a 5-year period. Pulmonary function and exercise capacity as evaluated by peak oxygen uptake (VO2) on progressive cycle ergometry were also followed over the same time. Using mixed effects models to estimate the slopes for the changes, scores on the SGRQ, the CRQ, the MRC and the HADS worsened in a statistically significant manner over time. However, changes only weakly correlated with changes in forced expiratory volume in 1s (FEV(1)) and peak (VO2). We demonstrated that although changes in pulmonary function and exercise capacity are well known in patients with COPD, patient reported outcomes such as health status, dyspnoea and psychological status also deteriorated significantly over time. In addition, deteriorations in patient reported outcomes only weakly correlated to changes in physiological indices. To capture the overall deterioration of COPD from the subjective viewpoints of the patients, patient reported outcomes should be followed separately from physiological outcomes.

Age Factors↗
PubMed2006

Postoperative complications after induction chemoradiotherapy in patients with non-small-cell lung cancer.

OBJECTIVE: This study evaluates the risks of postoperative complications in 124 patients with non-small-cell lung cancer who received pre-operative induction chemoradiotherapy and surgery. METHODS: All patients with non-small-cell lung cancer who underwent surgery after induction therapy between January 1990 and December 2003 were reviewed. We adopted univariate and multiple logistic regression models to identify predictors that increased the incidence of postoperative complications. RESULTS: Of 124 patients, 59 received carboplatin and docetaxel, 53 received cisplatin and etoposide, and 12 received other platinum-based combinations. Pre-operative thoracic radiotherapy was performed concurrently with chemotherapy. The median dose to the primary tumor was 40 Gy, and 29 patients (23.4%) received radiotherapy of more than 45 Gy before surgery. There were 25 pneumonectomies (20.2%). The overall postoperative mortality was 9 of 124 patients (7.3%), and complications developed in 54 patients (43.5%). Multivariate analysis demonstrated that only thoracic radiotherapy of more than 45 Gy predicted postoperative complications (P = 0.021; odds ratio, 3.620; 95% confidence interval, 1.214-10.797). CONCLUSIONS: Thoracic radiotherapy of more than 45 Gy, in combination with chemotherapy, was a significant risk factor for postoperative complications.

Adult↗
PubMed2006

Pulmonary infection of Mycobacterium avium-intracellulare complex with simultaneous organizing pneumonia.

A 67-year-old woman presented high-grade fever and dyspnea. Sputum culture confirmed Mycobacterium avium-intracellulare complex (MAC). Transbronchial lung biopsies revealed organizing pneumonia (OP) that was rapidly improved with corticosteroid. Five months after onset, a nodule emerged in the right lung. Although MAC was confirmed, the lesion was deemed too small to merit anti-mycobacterial chemotherapy. Four months later, diffuse infiltrates developed on chest X-ray. Bronchoalveolar lavage study identified MAC and exhibited OP patterns. We commenced antimycobacterial chemotherapy. The infiltrates almost completely improved within a month without corticosteroid.

Aged↗
PubMed2006

Prognosis of cough variant asthma: a retrospective analysis.

Patients with cough variant asthma, a common cause of chronic cough, may develop wheezing. We examined the determinants of this phenomenon and achievement of remission in 42 patients. During 4 years after diagnosis, wheezing developed in 13 of the patients. Early inhaled corticosteroid treatment was inhibitory against the development of wheezing by univariate analysis and by multivariate analysis with an odds ratio of 0.12 (95% confidence interval, 0.02 to 0.87, p = 0.037). Remission was achieved in 7 patients, who were younger than those without remission by univariate analysis (p = 0.048). Early treatment with inhaled corticosteroid may prevent the progression of cough variant asthma to classic asthma.

Adult↗
PubMed2006

Falls in blood pressure in patients with obstructive sleep apnoea after long-term nasal continuous positive airway pressure treatment.

OBJECTIVES: Effective treatment of obstructive sleep apnoea (OSA) with nasal continuous positive airway pressure (nCPAP) lowers blood pressure (BP). The long-term effects of nCPAP treatment on BP in OSA patients are not well known. The time period of such treatment sufficient to lower BP in OSA patients is also not known. We investigated compliance with long-term nCPAP therapy and its effects on BP. METHODS: This observational study involved 66 OSA patients [59 men, seven women; mean age, 51 (48-54) years; body mass index (BMI), 28.7 (27.7-29.7) kg/m; apnoea and hypopnoea, 50.3 (45.6-55.0)/h; 95% confidence intervals]. BP and BMI were measured before the study and at two checkpoints after usage of nCPAP [620 (552-688) and 1071 (1000-1143) days]. RESULTS: The different times between the first and second checkpoints for detecting objective compliance were 17 (4-30) min (P = 0.003). Diastolic BP decreased by 5.9 (3.1-8.7) mmHg after 600 days nCPAP treatment and by 4.6 (2.0-7.2) mmHg after 1000 days (P = 0.0006). Systolic BP and BMI did not change significantly. Usage of nCPAP treatment for a daily average of 3 h was needed to achieve a significant decrease in diastolic BP [7.4 (4.3-10.6) mmHg, P < 0.0001]. Diastolic BP of normotensive OSA patients did not change significantly by nCPAP treatment, but that of hypertensive OSA patients decreased significantly within 1 month-3 years of nCPAP treatment whether or not medication was used. CONCLUSIONS: In patients with severe OSA, the use of nCPAP for a daily average of 3 h would be sufficient to decrease the diastolic BP of hypertensive OSA patients.

Blood Pressure↗
PubMed2006

Comparison of airway dimensions in different anatomic locations on chest CT in patients with COPD.

OBJECTIVE: It is not well known whether there is heterogeneity in the airway dimensions at different anatomic locations in individual patients with COPD. The first objective was to compare airway dimensions of the basal segment bronchus between COPD patients and healthy controls. The second and third objectives were to compare the airway dimensions in two anatomic locations, and to investigate the relationship between CT measurements and pulmonary function among COPD patients. METHODS: Thirty males with COPD (aged 68.7 +/- 8.1 years) and 18 healthy males (aged 64.9 +/- 14.0 years) were enrolled in the study. COPD was diagnosed according to the criteria of the Global Initiative for Obstructive Lung Disease Workshop Report. Pulmonary function tests and CT scans were performed on all subjects. Airway dimensions and lung attenuation were automatically determined using methods that were validated with a phantom. RESULTS: Age, smoking index and height did not significantly differ between the COPD patients and healthy controls. The COPD patients had a significantly thicker airway wall than healthy controls. Among the COPD patients, there were no significant differences in the airway dimensions of bronchi in different segments; however, the airway and lung attenuation measurements of the lower lung field were more strongly correlated with FEV(1) than those of the upper lung field. CONCLUSION: Patients with COPD had no significant heterogeneity in airway dimensions at different anatomic locations. The airway and lung attenuation measurements of the lower lung field were more strongly correlated with airflow limitation than those of the upper lung field.

Aged↗
PubMed2006

Incidence of pulmonary hypertension and its clinical relevance in patients with sarcoidosis.

OBJECTIVE: To investigate the frequency of pulmonary hypertension (PH) and clinical parameters associated with PH in sarcoidosis patients. METHODS: A prospective, observational study was performed on 246 consecutive Japanese sarcoidosis patients followed up at the outpatient sarcoidosis clinic in the Central Clinic of Kyoto. The patients were evaluated for PH by Doppler echocardiography. Among these patients, 192 underwent pulmonary function tests. In addition, high-resolution CT of the lung was evaluated for the presence of lymph node enlargement, lung opacity, and thickening of bronchovascular bundles in 122 patients. PH was defined as estimated systolic pulmonary artery pressure (sPAP) > or = 40 mm Hg. The frequency of PH was evaluated, and clinical parameters were compared between patients with PH and those without PH. RESULTS: Among 212 patients who were successfully evaluated for sPAP, 12 patients (5.7%) had PH. Patients with PH had the following clinical characteristics: advanced chest radiographic stage, decreased oxygen saturation, predominantly male gender, and decreased percentage of predicted vital capacity, percentage of predicted FVC, percentage of predicted FEV1, percentage of predicted functional residual capacity, and percentage of predicted total lung capacity (%TLC). Multivariate logistic regression analysis showed that decreased %TLC was independently associated with PH. There was a weak negative correlation between sPAP and %TLC (p < 0.05). CONCLUSIONS: The frequency of PH in Japanese sarcoidosis patients was 5.7% evaluated with Doppler echocardiography. Decreased lung volume increases the risk of PH developing in patients with sarcoidosis.

Echocardiography, Doppler↗
PubMed2006

Clinical and radiographic indices associated with airflow limitation in patients with sarcoidosis.

BACKGROUND: Airflow limitation is found in some patients with sarcoidosis, and it is associated with a poor prognosis. The aim of this study was to investigate clinical and radiographic indices associated with airflow limitation in patients with sarcoidosis. METHODS: A prospective, observational study was performed on 228 consecutive sarcoidosis patients followed up at our patient clinic at the Central Clinic of Kyoto. Patients underwent pulmonary function tests, and high-resolution CT (HRCT) of the lung was evaluated for the presence of lymph node enlargement, lung opacity, reticular shadow, and thickening of bronchovascular bundles (BVB). Airflow limitation was defined as FEV(1)/FVC < 70%. Airway reversibility was tested in subjects with airflow limitation. The frequency of airflow limitation was evaluated, and clinical and radiographic parameters were compared between patients with and without airflow limitation. RESULTS: Among all 228 subjects, 20 subjects (8.8%) had airflow limitation, and none showed airway reversibility. Patients with airflow limitation were predominantly male, smokers, and had advanced chest radiographic stage, increased frequency of lung opacities, reticular shadows, and thickened BVB on HRCT. Stepwise regression analysis showed that chest radiographic stage IV, higher age, smoking, and thickened BVB were independently associated with lower FEV(1)/FVC. CONCLUSION: The frequency of airflow limitation was 8.8% in Japanese sarcoidosis patients. Chest radiographic stage IV, higher age, smoking, and thickened BVB were associated with airflow limitation in patients with sarcoidosis.

Adult↗
PubMed2006

[A questionnaire report concerning the actual situation of respiratory physicians in Japan].

A nation-wide questionnaire was carried out at the end of 2004 to elucidate the actual situation of respiratory physicians in Japan. The questionnaires were characterized by simultaneously looking into the actual situation in the departments of respiratory medicine, cardiology and gastroenterology. The number of the surveyed institution was 168, from which questionnaire replies were obtained from 79 general hospitals, 39 university hospitals and 10 hospitals mainly for tuberculosis. In general hospitals, compared to the departments of cardiology and gastroenterology, the full-time physician staff in the department of respiratory medicine per 10 inpatient beds was only 60.9% and 79.4%, while specialist staff were 54.9% and 68.4%, respectively. The numbers of deaths in the department of respiratory medicine per 10 inpatient beds were 186.9% and 132.6%, compared with in the departments of cardiology and gastroenterology, while those per full-time physicians were 271.9% and 148.5%, respectively. Thus, it was concluded that there was an obvious shortage in number of not only in respiratory specialists but also of all respiratory physicians. Furthermore, respiratory physicians were taking care of more severe patients than other colleagues.

Cardiology↗
PubMed2005

An N-glycan structure correlates with pulmonary metastatic ability of cancer cells.

N-Glycan structures on the surface of cancer cells have diverse structures and play significant roles in metastatic process. However, little is known about their roles in organ-selective metastasis. Our study revealed that an alpha1,6-fucosylated biantennary N-glycan structure designated A2G2F is characteristic of lungs, with far more abundant expression in normal human and murine lungs than in other organs. In this study, we further examined the role of A2G2F in pulmonary metastasis. We stained metastatic cancers by alpha1,6-fucose-specific Lens culinaris agglutinin lectin and revealed that pulmonary metastatic nodules more abundantly expressed alpha1,6-fucosylated N-glycans than hepatic metastatic nodules from common primary cancers. The most specific alpha1,6-fucosylated N-glycan structure in pulmonary metastatic cancer was identified to be A2G2F. Using a B16 melanoma cell metastasis model, we showed that A2G2F-rich B16 cells formed more pulmonary metastatic nodules than A2G2F-poor cells. Our results suggest that A2G2F plays a critical role in pulmonary metastasis.

Animals↗
PubMed2005

Dyspnoea with activities of daily living versus peak dyspnoea during exercise in male patients with COPD.

Dyspnoea measurements in chronic obstructive pulmonary disease (COPD) can be broadly divided into two categories: those that assess breathlessness during exercise, and those that assess breathlessness during daily activities. We investigated the relationships between dyspnoea at the end of exercise and during daily activities with clinical measurements and mortality in COPD patients. We examined 143 male outpatients with moderate to very severe COPD. The peak Borg score at the end of progressive cycle ergometry was used for the assessment of peak dyspnoea rating during exercise, and the Baseline Dyspnea Index (BDI) score was used for dyspnoea with activities of daily living. Relationships between these dyspnoea ratings with other clinical measurements of pulmonary function, exercise indices, health status and psychological status were then investigated. In addition, their relationship with the 5-year mortality of COPD patients was also analyzed to examine their predictive ability. Although the BDI score was significantly correlated with airflow limitation, diffusing capacity, exercise indices, health status and psychological status, the Borg score at the end of exercise had non-existent or only weak correlations with them. The BDI score was strongly significantly correlated with mortality, whereas the Borg score was not. Dyspnoea during daily activities was more significantly correlated with objective and subjective measurements of COPD than dyspnoea at the end of exercise. In addition, the former was more predictive of mortality. Dyspnoea with activities of daily living is considered to be a better measurement for evaluating the disease severity of COPD than peak dyspnoea during exercise.

Activities of Daily Living↗
PubMed2005

All-trans retinoic acid modulates radiation-induced proliferation of lung fibroblasts via IL-6/IL-6R system.

Although high-dose thoracic radiotherapy is an effective strategy for some malignancies including lung cancers and malignant lymphomas, it often causes complications of radiation fibrosis. To study the mechanism initiating tissue fibrosis, we investigated irradiation-induced cytokine production from human lung fibroblastic cells and found that IL-6 production was stimulated by irradiation. IL-6 is an autocrine growth factor for human myeloma cells, and retinoic acid is reported to inhibit their growth. Thus we evaluated the effect of all-trans retinoic acid (ATRA) on cell proliferation of lung fibroblasts along with the cytokine/receptor system. Irradiation-dependent stimulation of IL-6 production was correlated with increased NF-kappaB activity, and ATRA reduced this effect. Irradiation also increased the levels of mRNA for IL-6R and gp130, which were blocked by coexisting ATRA. Furthermore, IL-6 stimulated cell proliferation in dose-dependent manner but was overcome by pharmacological concentration of ATRA. These effects of ATRA were inhibited by rottlerin, which suggests ATRA abolished irradiation-induced stimulation through a PKCdelta-dependent pathway. Finally, we demonstrated that IL-6 transcripts in the lung were upregulated at 2 mo after irradiation, and the effect was inhibited by the intraperitoneal administration of ATRA. ATRA is expected to have an advantage for radiotherapy in its antitumor effects, as reported previously, and to prevent radiotherapy-induced pulmonary injury.

Animals↗