Publications by authors named "Shigeharu Myou"

Background And Objective: The purpose of this study was to evaluate the relationship between the wall structure assessed by using endobronchial ultrasonography (EBUS) and bronchial hyperresponsiveness in patients with asthma.

Methods: Twenty-four patients with stable asthma and 11 individuals without asthma were studied. EBUS was performed with a radial 20-MHz ultrasonic probe inserted into the intermediate bronchus undergoing flexible bronchoscopy to assess the airway wall structure.

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Background: Sinobronchial syndrome is a cause of chronic productive cough. Inflammatory mediators are involved in the pathophysiology of chronic productive cough. Accumulating evidences indicate that cyclooxygenase (COX)-2, one of the inducible isoforms of COX, is a key element in the pathophysiological process of a number of inflammatory disorders.

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Background: Chronic cough is the only symptom of cough variant asthma (CVA) and atopic cough (AC). Cysteinyl leukotriene receptor antagonists have been shown to be effective in CVA, but there are no reports on their effectiveness in AC. To evaluate the antitussive effect of montelukast, a leukotriene receptor antagonist, in CVA and AC.

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Background: Phosphodiesterase 4 selective inhibitor may prevent airway inflammation and remodeling.

Objective: The aim of this study was to investigate the effects of KF19514, a phosphodiesterase 4 and 1 dual inhibitor, on chronic airway inflammation and remodeling following chronic exposure to aerosolized antigen in mice.

Methods: Ovalbumin (OVA) was administered intraperitoneally to BALB/c mice on days 0 and 14, and the mice were then exposed to aerosolized OVA daily for 4 weeks.

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Background: "Atopic cough" is a new clinical entity that presents with isolated chronic bronchodilator-resistant cough accepted in the Japanese Respiratory Society Guidelines for Management of Cough. The essential features are eosinophilic tracheobronchitis, increased cough reflex sensitivity and an atopic constitution. It has been suggested that activated helper T lymphocytes and the cytokines which are produced by these cells are involved in the pathogenesis, but the relationship between helper T cell-derived cytokines and the airway cough reflex sensitivity remains unknown.

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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.

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Rationale: We hypothesized that cough stress of the airway wall results in a self-perpetuating cough-reflex cycle in which antigen-induced increase in cough-reflex sensitivity results in pathologic cough, and the cough in turn further amplifies cough-reflex sensitivity.

Objectives: To examine cough-reflex sensitivity in an experimental animal model.

Methods: We developed an experimental guinea pig model in which airway collapse similar to that in cough was induced by rapid negative pressure applied to the airway of artificially ventilated animals.

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Background And Objective: Surfactant dysfunction is a characteristic of bronchial asthma, but mechanisms of dysfunction following antigen exposure are not understood. The aim of this study was to examine whether bronchoalveolar lavage fluid (BALF) has surfactant degradation activity after antigen challenge, using an animal model of asthma.

Methods: BALF was collected 24 h after a challenge with aerosolized antigen solution in actively sensitized guinea pigs and from non-sensitized control guinea pigs.

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Inflammatory mediators are involved in the pathogenesis of airway inflammation, but the role of prostaglandin I2 (PGI2) remains obscure. This study was designed to investigate the role of PGI2 in cough reflex sensitivity of the asthmatic airway, which is characterized by chronic eosinophilic airway inflammation. The effect of beraprost, a chemically and biologically stable analogue of PGI2, on cough response to inhaled capsaicin was examined in 21 patients with stable asthma in a randomized, placebo-controlled cross over study.

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Cough due to cough-variant asthma (CVA) responds well to bronchodilators such as beta 2 adrenergic agonists. The aim of this study was to assess longitudinal changes of pulmonary function and bronchial responsiveness in CVA, which was treated with bronchodilators alone. Seventeen CVA patients recorded intensity and frequency of cough every day.

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The administration of Qvar (a hydrofluoroalkane-134a beclomethasone dipropionate; HFA-BDP) is highly useful for the treatment of patients with asthma. However, we found in a case of bronchial asthma that replacing the prior inhaled corticosteroids with Qvar resulted in temporary dyspnea and reduction in forced expiratory volume in 1 second (FEV1). Qvar contains beclomethasone dipropionate combined with absolute ethanol and an alternative to fluorocarbon.

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Background: It has been reported that nasal allergy influences the lower airway inflammation and functions. We elucidated whether nasal allergy would contribute to lower airway inflammation and functions.

Methods: 266 subjects aged 21-39 years were interviewed with special emphasis on history of asthma and nasal allergies (perennial allergic rhinitis (PAR) and seasonal allergic rhinitis (Japanese cedar pollinosis; PO)).

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Objectives: A predominance of type 2 helper T cells (Th2) in the bronchoalveolar space and peripheral blood is a well-accepted feature of bronchial asthma. However, the relationship between peripheral blood Th2 cells and asthma severity has not been thoroughly investigated.

Methods: As Th1 cells predominantly express the chemokine receptor CXCR3 and Th2 cells express CCR4, we assessed the distribution of peripheral blood CXCR3+ and CCR4+ lymphocytes using flow cytometry in 186 patients with asthma and 75 normal subjects.

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We report here a case of acute hypersensitivity pneumonitis induced by an oil fan heater. A 57-year-old man was admitted to our hospital because of fever, nonproductive cough, and dyspnea. Paeccilomyces variotii and Paeccilomyces nivea were identified from an oil fan heater in his house.

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Aims: Cough is a common symptom of bronchial asthma, a chronic inflammatory airway disease. Recently, the therapeutic effects of selective phosphodiesterase (PDE) inhibitors have been focused on bronchial asthma. This study was designed to investigate the clinical effect of PDE 3 inhibition on cough reflex sensitivity in elderly patients with bronchial asthma.

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Background: Late asthmatic response is observed following antigen challenge in actively, but not passively, sensitized guinea pigs. Although cough reflex sensitivity is increased after antigen challenge in actively sensitized guinea pigs, it is unknown whether the antigen-induced increase in cough reflex sensitivity develops in passively sensitized animals. The aim of this study was to compare the cough reflex sensitivity to inhaled capsaicin after an inhaled antigen challenge between actively and passively sensitized guinea pigs.

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Background: Cough variant asthma (CVA) is a cause of chronic cough and a precursor of typical asthma. We retrospectively examined the longitudinal change in bronchial responsiveness and cough reflex sensitivity in CVA patients with respect to the effect of long-term inhaled corticosteroids (ICS).

Methods: Provocative concentration of methacholine causing a 20% fall in forced expiratory volume in one second (PC20-FEV1) and provocative concentration of capsaicin eliciting 5 or more coughs (C5) were measured before treatment and during a follow up period following relief of cough (median; 2.

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A 32-year-old woman was transported to our hospital by ambulance because of loss of consciousness and breathing induced by drug intoxication. After general status was recovered, her arterial blood gas analysis under breathing room air revealed hypercapnia and hypoxemia which were caused by hypoventilation. After exclusion of apparent pulmonary, neuromuscular and central nerve diseases, she was diagnosed with primary alveolar hypoventilation syndrome.

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We examined the role of phosphoinositide 3-kinase (PI3K) in integrin-mediated eosinophil adhesion. Deltap85, a dominant-negative form of the class IA PI3K adaptor subunit, was fused to an HIV-TAT protein transduction domain (TAT-Deltap85). Recombinant TAT-Deltap85 inhibited interleukin (IL)-5-stimulated phosphorylation of protein kinase B, a downstream target of PI3K.

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Chronic eosinophilic bronchitis and bronchial hyperresponsiveness have been considered to be the fundamental features of bronchial asthma. However, the role of airway eosinophils in bronchial responsiveness in vivo has not been fully discussed. The aim of this study was to investigate the direct effect of airway eosinophil accumulation on bronchial responsiveness in vivo.

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Background: Activated T helper lymphocytes are present in the airway and their production of cytokines is important in the pathogenesis of asthma, however, the relationship between T helper lymphocyte-derived cytokines and airway cough reflex sensitivity remains unknown.

Methods: The effect of the orally active Th2 cytokine inhibitor suplatast tosilate on cough response to inhaled capsaicin was examined in eleven patients with stable atopic asthma and compared with patients having non-atopic asthma and chronic bronchitis (the latter of which is not related to Th2 cytokines). Capsaicin cough threshold, defined as the lowest concentration of capsaicin eliciting five or more coughs, was measured as an index of airway cough reflex sensitivity.

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A 24-year old man was hospitalized because of a severe asthmatic attack in August 2003. The asthma attack was well controlled by mechanical ventilation, intravenous hydrocortisone and inhaled beta2-agonist. Physical examination revealed sparse hair, reduced sweating and hypodontia.

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Although angiotensin II (Ang II) causes bronchoconstriction and bronchial hyperresponsiveness to methacholine in mildly asthmatic patients, the responsible mechanisms for these reactions are unclear. The authors examined the effect of intravenous infusion of Ang II on airway constriction in guinea pigs. Furthermore, the effects of subthreshold concentrations of Ang II on bronchial responsiveness to methacholine were investigated.

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We investigated the effect and mechanism(s) of PDE-4 treatment with concurrent beta2-adrenoceptor stimulation on human eosinophil adhesion mediated by beta2-integrin in vitro. Eosinophils were pretreated with either rolipram, a PDE-4 inhibitor, alone or combined with salmeterol, a beta2-adrenoceptor agonist, before activation with either eotaxin or IL-5. Beta2-integrin mediated adhesion was assessed as adherence to BSA, an established surrogate for ICAM-1.

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Phosphoinositide 3-kinase (PI3K) is thought to contribute to the pathogenesis of asthma by effecting the recruitment, activation, and apoptosis of inflammatory cells. We examined the role of class IA PI3K in antigen-induced airway inflammation and hyperresponsiveness by i.p.

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