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Dive into the research topics where Masanari Watanabe is active.

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Featured researches published by Masanari Watanabe.


Allergology International | 2011

Correlation between Asian dust storms and worsening asthma in Western Japan.

Masanari Watanabe; Akira Yamasaki; Naoto Burioka; Jun Kurai; Kazuhiko Yoneda; Atsushi Yoshida; Tadashi Igishi; Yasushi Fukuoka; Masaki Nakamoto; Hiromi Takeuchi; Hisashi Suyama; Toshiyuki Tatsukawa; Hiroki Chikumi; Shingo Matsumoto; Takanori Sako; Yasuyuki Hasegawa; Ryota Okazaki; Kazunori Horasaki; Eiji Shimizu

BACKGROUND Severe wind storms during spring in East Asia, called Asian dust storms (ADS), have been assessed in the past for their effect on health in Asian countries. Our objective was to study the ADS association with asthma symptoms in adult patients in Japan. METHODS We designed a telephone survey to assess ADS influence on upper and lower respiratory, ocular and cutaneous symptoms in 98 patients with adult asthma from April to May 2007. Peak expiratory flow (PEF) was also measured from February to May. RESULTS Worsening lower respiratory symptoms were noted by 22 of 98 patients during ADS in April, when Japanese cedar pollen levels also increased. During ADS in May, however, Japanese cedar and cypress pollen levels were not elevated, 11 patients had worsening of lower respiratory symptoms. None required emergency treatment for the exacerbation. Lower respiratory symptoms worsening most were cough and sputum; this was more common in patients with allergic rhinitis or atopy than in those without (P < 0.05). Min%Max differed significantly at 88.7 ± 6.6% during dust dispersion period, defined as the ADS day plus the next 6 days, versus 92.0 ± 5.3% during the 7-day period before a dust storm. CONCLUSIONS We found that ADS aggravated lower respiratory symptoms in adult patients with asthma, but this influence was mild.BACKGROUND Severe wind storms during spring in East Asia, called Asian dust storms (ADS), have been assessed in the past for their effect on health in Asian countries. Our objective was to study the ADS association with asthma symptoms in adult patients in Japan. METHODS We designed a telephone survey to assess ADS influence on upper and lower respiratory, ocular and cutaneous symptoms in 98 patients with adult asthma from April to May 2007. Peak expiratory flow (PEF) was also measured from February to May. RESULTS Worsening lower respiratory symptoms were noted by 22 of 98 patients during ADS in April, when Japanese cedar pollen levels also increased. During ADS in May, however, Japanese cedar and cypress pollen levels were not elevated, 11 patients had worsening of lower respiratory symptoms. None required emergency treatment for the exacerbation. Lower respiratory symptoms worsening most were cough and sputum; this was more common in patients with allergic rhinitis or atopy than in those without (P <0.05). Min%Max differed significantly at 88.7 ± 6.6% during dust dispersion period, defined as the ADS day plus the next 6 days, versus 92.0 ± 5.3% during the 7-day period before a dust storm. CONCLUSIONS We found that ADS aggravated lower respiratory symptoms in adult patients with asthma, but this influence was mild.


The Journal of Allergy and Clinical Immunology | 2009

Expression of functional leukotriene B4 receptors on human airway smooth muscle cells

Satoko Watanabe; Akira Yamasaki; Kiyoshi Hashimoto; Yasushi Shigeoka; Hiroki Chikumi; Yasuyuki Hasegawa; Takashi Sumikawa; Miyako Takata; Ryota Okazaki; Masanari Watanabe; Tsuyoshi Yokogawa; Miki Yamamura; Tatsuya Hayabuchi; William T. Gerthoffer; Andrew J. Halayko; Eiji Shimizu

BACKGROUND Leukotriene B4 (LTB4) increases in induced sputum and exhaled breath condensate in people with asthma. Furthermore, the T(H)2-type immune response and airway hyperresponsiveness induced by ovalbumin sensitization is markedly suppressed in LTB4 receptor (BLT) 1 null mice. These studies suggest that LTB4 may contribute to asthma pathophysiology. However, the direct effects of LTB4 on human airway smooth muscle (ASM) have not been studied. OBJECTIVES We sought to determine the expression of LTB4 receptors on human ASM and its functional role in mediating responses of human ASM cells, and the effect of LTB4 on these cells. METHODS Immunohistochemistry, RT-PCR, Western blotting, and flow cytometry were used to determine the expression of LTB4 receptors. To determine the effect of LTB4 on human ASM cells, cell proliferation was assessed by counting cells, and chemokinesis was assessed by gold particle phagokinesis assay. RESULTS We confirmed expression of both BLT1 and BLT2 in human ASM cells in bronchial tissue and in cell culture. LTB4 markedly induced cyclin D1 expression, proliferation, and chemokinesis of human ASM cells. LTB4 also induced phosphorylation of both p42/p44 mitogen-activated protein kinase (MAPK) and downstream PI3 kinase effector, Akt1. However, we observed no induction of c-Jun N-terminal kinase or p38 MAPK. Notably, LTB4-induced migration and proliferation of ASM cells were inhibited by the BLT1 specific antagonist, U75302, and by inhibitors of p42/p44 MAPK phosphorylation (U1026), and PI3 kinase (LY294002). CONCLUSIONS These observations are the first to suggest a role for a LTB4-BLT1 signaling axis in ASM responses that may contribute to the pathogenesis of airway remodeling in asthma.


Allergology International | 2011

Pollen Augments the Influence of Desert Dust on Symptoms of Adult Asthma Patients

Masanari Watanabe; Tadashi Igishi; Naoto Burioka; Akira Yamasaki; Jun Kurai; Hiromi Takeuchi; Takanori Sako; Atsushi Yoshida; Kazuhiko Yoneda; Yasushi Fukuoka; Masaki Nakamoto; Yasuyuki Hasegawa; Hiroki Chikumi; Shingo Matsumoto; Sayaka Minato; Kazunori Horasaki; Eiji Shimizu

BACKGROUND East Asian desert dust storms that occur during mainly spring are called Asian dust storms (ADS). Our objective was to study the association of pollen and ADS with symptoms of adult asthma patients in Japan. METHODS We designed a telephone survey to investigate the upper and lower respiratory, ocular, and skin symptoms of asthma patients during ADS in February, March, and December on 2009. Peak expiratory flow (PEF) was also measured from February to May. RESULTS We surveyed 106 patients in February, 101 patients in March, and 103 patients in December. In February and March, Japanese cedar and/or cypress pollen was also in the atmosphere during ADS, but no pollen was identified during December survey. Worsening of upper or lower respiratory, ocular, or skin symptoms was noted by 20.8% of patients in February, 33.7% in March, and 16.5% in December. Worsening of symptoms was significantly more common in March than in February or December. Two patients needed emergency treatment for exacerbation during ADS in March, but no patient needed hospitalization in any period. There was no significant difference of the daily morning PEF/personal best PEF ratio between ADS days and control days. However, in patients with worsening of upper and/or lower respiratory tract symptoms, the daily morning PEF/personal best ratio was significantly associated with the atmospheric level of particulate matter, but not with levels of pollen or other air pollutants. CONCLUSIONS Pollen augmented symptoms in adult asthma patients, but ADS on its own also were able to aggravate symptoms and pulmonary function.


Journal of Asthma | 2014

Effects on asthma and induction of interleukin-8 caused by Asian dust particles collected in western Japan.

Masanari Watanabe; Jun Kurai; Katsuyuki Tomita; Hiroyuki Sano; Satoshi Abe; Rumiko Saito; Sayaka Minato; Tadashi Igishi; Naoto Burioka; Takanori Sako; Kazuhito Yasuda; Masaaki Mikami; Shinichi Kurita; Hirokazu Tokuyasu; Yasuto Ueda; Tatsuya Konishi; Akira Yamasaki; Setsuya Aiba; Mitsuo Oshimura; Eiji Shimizu

Abstract Objective: Asian dust storms (ADS) contain various airborne particles that may augment airway inflammation by increasing the level of interleukin-8. The objective of the study was to investigate the association of exposure to an ADS with worsening of symptoms of adult asthma and the effect of ADS particles on interleukin-8 transcriptional activity. Methods: The subjects were 112 patients with mild to moderate asthma who recorded scores for their daily upper and lower respiratory tract symptoms and measured morning peak expiratory flow (PEF) from March to May 2011. Interleukin-8 transcriptional activity was assessed in THP-G8 cells that were exposed to airborne particles collected during days of ADS exposure. Results: Of the 112 patients, 31 had comorbid allergic rhinitis (AR) and/or chronic sinusitis (CS), and had worsened scores for upper respiratory tract symptoms on ADS days compared to non-ADS days. Scores for lower respiratory tract symptoms during ADS days were higher than non-ADS days in all patients. Three patients also had unscheduled hospital visits for exacerbation of asthma on ADS days. However, there was no significant difference in daily morning PEF between ADS and non-ADS days. Airborne particles collected on ADS days induced interleukin-8 transcriptional activity in THP-G8 cells compared to the original soil of the ADS. Conclusion: Exposure to an ADS aggravates upper and lower tract respiratory symptoms in patients with adult asthma. ADS airborne particles may increase airway inflammation through enhancement of interleukin-8 transcriptional activity.


Cancer Science | 2012

Diagnostic and prognostic impact of serum‐soluble UL16‐binding protein 2 in lung cancer patients

Kosuke Yamaguchi; Hiroki Chikumi; Asuka Shimizu; Miyako Takata; Naoki Kinoshita; Kiyoshi Hashimoto; Masaki Nakamoto; Shinji Matsunaga; Jun Kurai; Naomi Miyake; Shingo Matsumoto; Masanari Watanabe; Akira Yamasaki; Tadashi Igishi; Naoto Burioka; Eiji Shimizu

UL16‐binding protein 2 (ULBP2) is one of the ligands for NKG2D (NKG2DL). ULBP2 expression is induced in transformed cells and is recognized by immune effector cells via the activating NKG2D immunoreceptor. Soluble forms of NKG2DL have been reported in the serum of patients with several types of cancer. The present study investigated the diagnostic and prognostic significance of serum‐soluble ULBP2 (sULBP2) in lung cancer patients. We used flow cytometry to evaluate the surface expression of NKG2DL by various lung cancer cells, while sULBP2 was measured using our original ELISA. In addition, the immunological effect of sULBP2 on peripheral blood mononuclear cells (PBMC) was examined by the 51Cr release assay. We found that ULBP2 was highly expressed and that the sULBP2 level was elevated in supernatants of cultured non‐small‐cell lung cancer (NSCLC) cells as well as in the serum of NSCLC patients. ULBP2 levels were especially high in squamous cell carcinoma (SQ) patients. Clinical stage IIIB and IV NSCLC patients with a sULBP2 level ≥8.7 pg/mL showed significantly shorter survival than patients with sULBP2 <8.7 pg/mL. In multivariate analysis, a sULBP2 level ≥8.7 pg/mL (hazard ratio [HR], 2.13; P = 0.038) and clinical stage IV (HR, 2.65; P = 0.019) were independent determinants of a poor outcome. As a possible mechanism, we demonstrated that sULBP2 directly suppresses the cytolytic activity of PBMC. In conclusion, ULBP2 is the most significant NKG2DL for lung cancer, and sULBP2 is useful in the diagnosis of SQ and as a prognostic indicator for patients with advanced NSCLC. (Cancer Sci, doi: 10.1111/j.1349‐7006.2012.02330.x, 2012)


International Journal of Environmental Health Research | 2009

Environmental tobacco smoke and its effect on the symptoms and medication in children with asthma

Akira Yamasaki; Keichi Hanaki; Katsuyuki Tomita; Masanari Watanabe; Yasuyuki Hasagawa; Ryota Okazaki; Tadashi Igishi; Kenta Horimukai; Kouji Fukutani; Yuji Sugimoto; Mitsunobu Yamamoto; Kazuhiro Kato; Toshikazu Ikeda; Tatsuya Konishi; Hirokazu Tokuyasu; Hiroki Yajima; Hitoshi Sejima; Takeshi Isobe; Eiji Shimizu

Environmental tobacco smoke (ETS) worsens asthmatic symptoms. We analyzed the relationship between levels of ETS and asthmatic symptoms and medication. We asked parents of 282 asthmatic children about the general condition, smoke exposure and medication. Patients were classified into three groups: no-ETS (no smoking), mild-ETS (smoking in the house but not in the same room as patient), and heavy-ETS (smoking in the same room as patient). We classified 116 children in no-ETS group, 124 children in mild-ETS group and 42 children in heavy-ETS group. The symptoms were worst and prevalence of leukotriene receptor antagonist and long-acting β2-agonist use were highest in heavy-ETS group. However, there was no statistical difference between no-ETS and mild-ETS groups in prevalence of anti-asthmatic drug use and symptoms. We conclude that a smoking ban in rooms used by asthmatic children is an easy way to reduce ETS, asthmatic symptoms and the use of anti-asthmatic drugs.


BioMed Research International | 2015

Decreased Pulmonary Function in School Children in Western Japan after Exposures to Asian Desert Dusts and Its Association with Interleukin-8

Masanari Watanabe; Hisashi Noma; Jun Kurai; Hiroyuki Sano; Rumiko Saito; Satoshi Abe; Yutaka Kimura; Setsuya Aiba; Mitsuo Oshimura; Akira Yamasaki; Eiji Shimizu

The objective of the study was to investigate the influence of Asian dust storms (ADS) on pulmonary function of school children and the relationship of this effect with interleukin-8. Morning peak expiratory flow (PEF) was measured daily in 399 children from April to May 2012 and in 384 of these children from March to May 2013. The data were analyzed for an association between ADS events and PEF by linear mixed models. Interleukin-8 transcriptional activity was assessed in THP-G8 cells stimulated by airborne particles collected on ADS days. Seven ADS days were identified: April 23 and 24, 2012; March 8 to 10, 2013; and March 19 and 20, 2013. Changes in PEF after ADS exposure were −8.17 L/min (95% confidence interval, −11.40 to −4.93) in 2012 and −1.17 L/min (−4.07 to 1.74) in 2013, and there was a significant difference between 2012 and 2013. Interleukin-8 transcriptional activity was significantly higher in 2012 at 10.6 ± 2.9-fold compared to 3.7 ± 0.4 in March 8 to 10, 2013, and 2.3 ± 0.2 in March 19 and 20, 2013. The influence of ADS events on pulmonary function of children differs with each ADS event and may be related to interleukin-8 production.


International Journal of Chronic Obstructive Pulmonary Disease | 2010

COPD is frequent in conditions of comorbidity in patients treated with various diseases in a university hospital.

Akira Yamasaki; Kiyoshi Hashimoto; Yasuyuki Hasegawa; Ryota Okazaki; Miki Yamamura; Tomoya Harada; Shizuka Ito; Soichiro Ishikawa; Hiroki Takami; Masanari Watanabe; Tadashi Igishi; Yuji Kawasaki; Eiji Shimizu

Background Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death and loss of disability-adjusted life-years. However, many COPD patients are not diagnosed because of underrecognition or underdiagnosis of this disease among many patients and physicians. One possible reason is underrecognition of spirometry. In this study, we examined the prevalence of airflow limitation and underlying disease in patients with airflow limitation. Methodology From April 2006 to March 2008, patients who had spirometry performed were examined. The original disease of patients, pulmonary function tests, smoking status, and respiratory symptoms were surveyed from their medical records. Results Of all patients who had spirometry performed, 15.8% showed airflow limitation (FEV1/FVC < 0.7). A variety of diseases were observed in patients with airflow limitation. Among all diseases, cardiovascular disease was the highest and gastrointestinal malignant disease had the second highest prevalence in patients with airflow limitation. Conclusion COPD might be frequent in conditions of comorbidity in patients treated for various diseases. Attention should be paid to the possibility of co-existence of COPD and the influence of COPD on these patients.


Acta Oncologica | 2004

Cellular immune profile in patients with non-small cell lung cancer after weekly paclitaxel therapy.

Takanori Sako; Naoto Burioka; Kazuhito Yasuda; Katsuyuki Tomita; Masanori Miyata; Jun Kurai; Hiroki Chikumi; Masanari Watanabe; Hisashi Suyama; Yasushi Fukuoka; Yasuto Ueda; Eiji Shimizu

Paclitaxel is a new agent for advanced non-small cell lung cancer (NSCLC). Weekly doses may enhance antitumor activity while minimizing toxicity, but little is known about immune recovery. Paclitaxel (80 mg/m2) was administered to 10 patients with NSCLC, weekly during 3-week cycles. Natural killer (NK) activity, CD3−CD16+CD56+ NK cells, and differential counts were monitored. NK activity appeared in all patients after treatment with paclitaxel therapy. NK activity showed a 27±9% decrease (mean±SE) on protocol day 8 and a 37±7% decrease on day 15 (p<0.05) recovering to 89±5% of baseline on day 29. With weekly paclitaxel, a decrease in NK cell function persisted through the first cycle but then recovered. Weekly paclitaxel may be less immunosuppressive than agents such as cisplatin.


Pulmonary Pharmacology & Therapeutics | 2015

γ-Tocotrienol reduces human airway smooth muscle cell proliferation and migration.

Tomoya Harada; Akira Yamasaki; Hiroki Chikumi; Kiyoshi Hashimoto; Ryota Okazaki; Miki Takata; Takehito Fukushima; Masanari Watanabe; Jun Kurai; Andrew J. Halayko; Eiji Shimizu

AIMS Vitamin E is an antioxidant that occurs in 8 different forms (α, β, γ, and δ tocopherol and tocotrienol). Clinical trials of tocopherol supplementation to assess the impact of antioxidant activity in asthma have yielded equivocal results. Tocotrienol exhibits greater antioxidant activity than tocopherol in several biological phenomena in vivo and in vitro. We tested the effect of tocotrienol on human airway smooth muscle (ASM) cell growth and migration, both of which mediate airway remodeling in asthma. MAIN METHODS We measured platelet-derived growth factor-BB (PDGF-BB)-induced ASM cell proliferation and migration by colorimetric and Transwell migration assays in the presence and absence of γ-tocotrienol (an isoform of tocotrienol). KEY FINDINGS PDGF-BB-induced ASM cell proliferation and migration were inhibited by γ-tocotrienol. This effect was associated with inhibition of RhoA activation, but it had no effect on p42/p44 mitogen-activated protein kinase (MAPK) or Akt1 activation. We confirmed that pharmacological inhibition of Rho kinase activity was sufficient to inhibit PDGF-BB-induced ASM cell proliferation and migration. SIGNIFICANCE γ-Tocotrienol could impart therapeutic benefits for airway remodeling in asthma by inhibiting human ASM cell proliferation and migration.

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