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Featured researches published by Ryoji Ito.


Chest | 2010

Comparative Evaluation of Serum Markers in Pulmonary Sarcoidosis

Seigo Miyoshi; Hironobu Hamada; Toru Kadowaki; Naohiko Hamaguchi; Ryoji Ito; Kazunori Irifune; Jitsuo Higaki

BACKGROUND Although several serum markers have shown their ability to reflect lymphocytic alveolitis and disease progression in pulmonary sarcoidosis, to our knowledge no prior study has made comparative evaluations of these markers. METHODS Forty-three patients with pulmonary sarcoidosis were enrolled. BAL fluid (BALF) cells were analyzed, and serum levels of serum amyloid A (SAA), soluble interleukin 2 receptor (sIL-2R), lysozyme, angiotensin-converting enzyme (ACE), and the mucin-like, high-molecular-weight glycoprotein KL-6 were measured at disease presentation. Clinical data, including chest radiographs, were collected at presentation and during follow-ups. Univariate and multivariate analyses were used to identify markers best predictive of increased parenchymal infiltration. RESULTS Significantly higher serum levels of sIL-2R, lysozyme, and KL-6 were found in patients with parenchymal infiltration compared with those without parenchymal infiltration. The numbers of total cells and lymphocytes in BALF were significantly higher in patients with parenchymal infiltration. Serum levels of sIL-2R, lysozyme, and KL-6 were significantly correlated with the numbers of total cells, lymphocytes, and CD4(+) T lymphocytes in BALF. At the cutoff levels determined by receiver operating characteristic curves, sIL-2R, lysozyme, KL-6 serum levels, and the number of BAL lymphocytes showed significant correlations with increased parenchymal infiltrations by univariate analysis. However, multivariate analysis revealed that only KL-6 was a predictor of increased parenchymal infiltration. CONCLUSION Our results suggest that initial serum sIL-2R, lysozyme, and KL-6 levels may reflect lymphocytic alveolitis in pulmonary sarcoidosis. Furthermore, initial serum KL-6 tends to associate with increased parenchymal infiltration in pulmonary sarcoidosis.


Clinical and Experimental Hypertension | 2005

Successful Treatment of Obstructive Sleep Apnea Syndrome Improves Autonomic Nervous System Dysfunction

Ryoji Ito; Hironobu Hamada; Akihito Yokoyama; Miki Oshima; Hitoshi Katayama; Hiroshi Ohnishi; Toru Kadowaki; Sanae Ishimaru; Kazunori Irifune; Jitsuo Higaki

Autonomic nervous system (ANS) dysfunction may be implicated in the subsequent development of cardiovascular disease in patients with obstructive sleep apnea syndrome (OSAS). To confirm the relation between OSAS and ANS dysfunction, we prospectively investigated ANS function in 7 patients with moderate or severe OSAS; 7 healthy age-matched volunteers were for control. We also studied ANS function before and after treatment in the patients with OSAS to evaluate the effect of OSAS treatment on ANS dysfunction. The body mass index of patients with OSAS was 32.2 (27.4–45) (median [range]) kg/m2. The patients were treated by nasal continuous positive airway pressure (n = 5) or uvulopalatopharyngoplasty (n = 2). The apnea/hypopnea index decreased markedly from 42.1 (30.6–77.2) events/hr of sleep before treatment to 2.3 (1.4–3.8) after treatment. To evaluate ANS function, the coefficient of variation of the RR interval (CV-RR) and corrected QT (QTc) interval on the electrocardiogram at rest and the heart rate (HR) responses to blood pressure (BP) changes during the Valsalva maneuver were studied. Baseline HR of OSAS patients was significantly higher than that of the control subjects (p < .05). The Valsalva ratio (VR), baroreflex sensitivity (BRS), and CV-RR values in patients with OSAS were significantly lower than those of the control subjects (all, p < .005). However, there were no significant differences in systolic and diastolic BP or QTc intervals. After treatment, VR, BRS, and CV-RR values increased significantly compared with those before treatment in patients with OSAS (all, p < .05). There were no significant differences in systolic and diastolic BP, HR, or QTc intervals measured before and after treatment. These results suggest that impaired ANS function is present in patients with OSAS and can be improved by successful treatment of OSAS.


Drug Design Development and Therapy | 2013

Usefulness of a selective neutrophil elastase inhibitor, sivelestat, in acute lung injury patients with sepsis.

Seigo Miyoshi; Hironobu Hamada; Ryoji Ito; Hitoshi Katayama; Kazunori Irifune; Toshimitsu Suwaki; Norihiko Nakanishi; Takanori Kanematsu; Kentaro Dote; Mayuki Aibiki; Takafumi Okura; Jitsuo Higaki

Background Neutrophil elastase plays a crucial role in the development of acute lung injury (ALI) in patients with systemic inflammatory response syndrome (SIRS). The clinical efficacy of the neutrophil elastase inhibitor, sivelestat, for patients with ALI associated with SIRS has not been convincingly demonstrated. The aim of this study was to determine if there are clinical features of patients with this condition that affect the efficacy of sivelestat. Methods This was a retrospective study of 110 ALI patients with SIRS. Clinical information, including the etiology of ALI, the number of organs failing, scoring systems for assessing the severity of illness, and laboratory data, was collected at the time of diagnosis. Information on the number of ventilator-free days (VFDs) and changes in PaO2/FIO2 (ΔP/F) before and 7 days after the time of ALI diagnosis was also collected. The effect of sivelestat on ALI patients was also examined based on whether they had sepsis and whether their initial serum procalcitonin level was ≥0.5 ng/mL. Results There were 70 patients who were treated with sivelestat and 40 control patients. VFDs and ΔP/F were significantly higher in the treated patients than in the control patients. However, there was no significant difference in the patient survival rate between the two groups. Sivelestat was more effective in ALI patients with a PaO2/FIO2 ratio ≥ 140 mmHg or sepsis. Sivelestat significantly prolonged survival and led to higher VFDs and increased ΔP/F in septic patients and patients with initial serum procalcitonin levels ≥ 0.5 ng/mL. Conclusion The results may facilitate a future randomized controlled trial to determine whether sivelestat is beneficial for ALI patients with sepsis.


Cancer Science | 2010

In vitro and in vivo therapeutic efficacy of the PPAR‐γ agonist troglitazone in combination with cisplatin against malignant pleural mesothelioma cell growth

Naohiko Hamaguchi; Hironobu Hamada; Seigo Miyoshi; Kazunori Irifune; Ryoji Ito; Tatsuhiko Miyazaki; Jitsuo Higaki

Malignant pleural mesothelioma (MPM), an aggressive and refractory tumor type, is increasing in frequency throughout the world. Peroxisome proliferator activated receptor‐γ (PPAR‐γ) agonists have anticancer activity against several cancer cell lines in vitro and in vivo. However, there have been no reports that PPAR‐γ agonists induce growth inhibition of MPM cell lines. In this study, we investigated the inhibitory effect of a PPAR‐γ agonist in combination with an anticancer agent on MPM cell growth in vitro and in vivo. We examined the therapeutic efficacy of the PPAR‐γ agonist troglitazone (TGZ) in combination with cisplatin against a human MPM cell line, both in vitro and orthotopically inoculated into severe combined immunodeficient (SCID) mice. Troglitazone (TGZ) alone inhibited MPM cell growth in vitro in a dose‐dependent manner via induction of G1 cell cycle arrest and apoptosis. The combination of TGZ and cisplatin showed an additive inhibitory effect on MPM cell growth compared to treatment with either individual drug. Treatment with 500 mg/kg or 1000 mg/kg TGZ effectively inhibited the production of thoracic tumors and pleural effusion in EHMES‐10 cell‐bearing SCID mice. Moreover, treatment with 500 mg/kg TGZ in combination with 3 mg/kg cisplatin more effectively prolonged survival compared to treatment with either individual drug. These results suggest that TGZ in combination with cisplatin may become a novel therapy for MPM. (Cancer Sci 2010)


Phytomedicine | 2011

Antitussive effect of bakumondoto a fixed kampo medicine (six herbal components) for treatment of post-infectious prolonged cough: controlled clinical pilot study with 19 patients.

Kazunori Irifune; Hironobu Hamada; Ryoji Ito; Hitoshi Katayama; Akira Watanabe; Aki Kato; Seigo Miyoshi; Naohiko Hamaguchi; Ryo Toyozawa; Sachiko Hamaguchi; Masahiro Abe; Kazutaka Nishimura; Jitsuo Higaki

Bakumondoto (TJ-29) is a traditional herbal medicine that has been used in Japan for the treatment of bronchitis, bronchial asthma, and cough. This study investigated the effect of TJ-29 for the treatment of post-infectious prolonged cough. We performed a multicenter randomized controlled trial treating patients without (group A, n=11) or with TJ-29 (group B, n=8) for a total of 2 weeks using a beta 2 stimulant as the basal agent. Efficacy and safety were compared by a cough diary, VAS and sleeping questionnaire. At 4 and 5 days after treatment, the cough score of group B showed significant improvement compared with group A, demonstrating an early antitussive effect. At the assessment 2 weeks after treatment start, both groups showed similar levels of improvement in the cough score. No significant difference was observed in the VAS and the sleeping questionnaire items. In conclusion, oral TJ-29 administration could be useful and safe for the treatment of post-infectious prolonged cough.


PLOS ONE | 2014

Cell Stress Induces Upregulation of Osteopontin via the ERK Pathway in Type II Alveolar Epithelial Cells

Aki Kato; Takafumi Okura; Chizuru Hamada; Seigo Miyoshi; Hitoshi Katayama; Jitsuo Higaki; Ryoji Ito

Osteopontin (OPN) is a multifunctional protein that plays important roles in cell growth, differentiation, migration and tissue fibrosis. In human idiopathic pulmonary fibrosis and murine bleomycin-induced lung fibrosis, OPN is upregulated in type II alveolar epithelial cells (AEC II). However, the mechanism of OPN induction in AEC II is not fully understood. In this study, we demonstrate the molecular mechanism of OPN induction in AEC II and elucidate the functions of OPN in AEC II and lung fibroblasts. Human lung adenocarcinoma cells (A549) and mouse alveolar epithelial cells (MLE12), used as type II alveolar epithelial cell lines for in vitro assays, and human pulmonary alveolar epithelial cells (HPAEpiC) were treated with either bleomycin, doxorubicin or tunicamycin. The mechanism of OPN induction in these cells and its function as a pro-fibrotic cytokine on A549 and lung fibroblasts were analyzed. The DNA damaging reagents bleomycin and doxorubicin were found to induce OPN expression in A549, MLE12 and HPAEpiC. OPN expression was induced via activation of the extracellular signal-regulated protein kinase (ERK)-dependent signaling pathway in A549 and MLE12. The endoplasmic reticulum (ER) stress-inducing reagent tunicamycin induced OPN mRNA expression in A549, MLE12 and HPAEpiC, and OPN mRNA expression was induced via activation of the ERK-dependent signaling pathway in A549 and MLE12. Another ER stress-inducing reagent thapsigargin induced the expression of OPN mRNA as well as the subsequent production of OPN in A549 and MLE12. Furthermore, OPN promoted the proliferation of A549 and the migration of normal human lung fibroblasts. Inhibition of OPN by small interference RNA or neutralizing antibody suppressed both of these responses. The results of this study suggest that cell stress induces the upregulation of OPN in AEC II by signaling through the ERK pathway, and that upregulated OPN may play a role in fibrogenesis of the lung.


Respirology | 2005

Metastatic renal cell carcinoma presenting as multiple pleural tumours

Hiroshi Ohnishi; Masahiro Abe; Hironobu Hamada; Akihito Yokoyama; Takeru Hirayama; Ryoji Ito; Kazutaka Nishimura; Jitsuo Higaki

Abstract:  A 66‐year‐old man was admitted with dyspnoea. Chest X‐ray and chest computed tomography (CT) demonstrated a left‐sided pleural effusion and multiple tumours, suggesting malignant mesothelioma in the left pleural space, but there were no pulmonary lesions. However, abdominal CT revealed a right renal tumour. An ultrasonography‐guided needle biopsy of the pleural mass provided evidence of metastatic renal cell carcinoma (RCC). The pleural lesions dramatically decreased in size following right radical nephrectomy and subsequent interferon‐α treatment. While the thorax is a frequently affected site of RCC, sole pleural metastases are rare and are often secondary to lung involvement. Batsons plexus, a network of vertebral valve‐less veins with multiple connections, is likely responsible for the contralateral pleural metastases of RCC.


International Journal of Oncology | 2012

Antitumor activity of MEK and PI3K inhibitors against malignant pleural mesothelioma cells in vitro and in vivo

Seigo Miyoshi; Hironobu Hamada; Naohiko Hamaguchi; Aki Kato; Hitoshi Katayama; Kazunori Irifune; Ryoji Ito; Tatsuhiko Miyazaki; Takafumi Okura; Jitsuo Higaki

Malignant pleural mesothelioma (MPM) is an aggressive malignancy for which there is no approved targeted therapy. We examined the therapeutic efficacy of the mitogen-activated protein kinase kinase (MEK) and phosphatidylinositol 3-kinase (PI3K) inhibitors against human MPM cell lines both in vitro and orthotopically inoculated into severe combined immunodeficient (SCID) mice. In addition, the molecular mechanisms of these agents were confirmed in vitro and in vivo. The MEK or the PI3K inhibitor suppressed MPM cell growth in vitro in a dose-dependent manner via induction of G1 cell cycle arrest and apoptosis. In addition, combined use of the MEK and PI3K inhibitors showed an additive or synergistic inhibitory effect on MPM cell growth compared to treatment with either individual drug. Treatment with MEK or PI3K inhibitor suppressed the production of thoracic tumors and pleural effusion and prolonged the survival time of EHMES-10 cell-bearing SCID mice. The combination therapy more effectively prolonged the survival time compared to treatment with either individual drug. Immunohistochemical and western blot analysis of thoracic tumors suggested that these agents induced cell cycle arrest, apoptosis and inhibition of tumor angiogenesis. Our results suggest that a combination of MEK and PI3K inhibitors is a promising therapeutic strategy for MPM.


Geriatrics & Gerontology International | 2012

Pasteurella multocida pneumonia: Zoonotic transmission confirmed by molecular epidemiological analysis

Seigo Miyoshi; Hironobu Hamada; Ai Miyoshi; Ryoji Ito; Naohiko Hamaguchi; Shinobu Murakami; Hitoshi Miyamoto; Takao Takeuchi; Takafumi Okura; Jitsuo Higaki

Semin Oncol 2004; 31 (6 Suppl 18): 29–36. 5 Mendoza AR, Tomlinson MJ. The split denture: a new technique for artificial saliva reservoirs in mandibular dentures. Aust Dent J 2003; 48: 190–194. 6 Michael T, Leila J, Ship JA. Hyposalivation, xerostomia and the complete denture-A systematic review. J Am Dent Assoc 2008; 139: 146–150. 7 Sheiham A, Steele JG, Marcenes W et al. The relationship among dental status, nutrient intake, and nutritional status in older people. J Dent Res 2001; 80: 408–413. 8 Lindstrom RE, Pawelchak J, Heyd A, Tarbet WJ. Physicalchemical aspects of denture retention and stability: a review of the literature. J Prosthet Dent 1979; 42: 371–375. 9 Kikuchi M, Ghani F, Watanabe M. Method for enhancing retention in complete denture bases. J Prosthet Dent 1999; 81: 399–403. 10 Ship JA, Pillemer SR, Baum BJ. Xerostomia and the geriatric patient. J Am Geriatr Soc 2002; 50: 535–543. 11 Givens E Jr. Update on xerostomia: current treatment modalities and future trends. Gen Dent 2006; 54: 99–101. 12 Brennan MT, Shariff G, Lockhart PB, Fox PC. Treatment of xerostomia: a systematic review of therapeutic trials. Dent Clin North Am 2002; 46: 847–856. 13 Cassolato SF, Turnbull RS. Xerostomia: clinical aspects and treatment. Gerodontology 2003; 20: 64–77. 14 Niedermeier W, Huber M, Fischer D et al. Significance of saliva for the denture-wearing population. Gerodontology 2000; 17: 104–118. 15 Márton K, Boros I, Fejérdy P, Madléna M. Evaluation of unstimulated flow rates of whole and palatal saliva in healthy patients wearing complete dentures and in patients with Sjogren’s syndrome. J Prosthet Dent 2004; 91: 577–581.


Journal of Asthma | 2006

Effect of Inhalated Bronchodilators on Air Trapping in Patients with Stable Asthma

Ryoji Ito; Akihito Yokoyama; Hironobu Hamada; Yoshifumi Yasuhara; Nobuoki Kohno; Jitsuo Higaki

Air trapping is frequently observed during high-resolution computed tomography (HRCT) of patients with asthma, but whether the condition is reversible has not been thoroughly investigated. The aim of the present study was to evaluate reversibility of air trapping in response to bronchodilator. Ten never-smokers with stable asthma enrolled in the study. Spirometry and HRCT were performed before and after bronchodilator inhalation. Air trapping remained unchanged, although significant reversibility of FEV1 was observed. Air trapping scores correlated significantly with airway wall thickness. These observations suggest that air trapping is irreversible and that it represents structural remodeling of small airways in patients with stable asthma.

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