Minoru Takeuchi

Kyoto Sangyo University, Kioto, Kyōto, Japan

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Publications (25)57.75 Total impact

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    ABSTRACT: A highly versatile nanoplatform that couples mesoporous silica nanoparticles (MSN) with an aerosol technology to achieve direct nanoscale delivery to the respiratory tract is described. This novel method can deposit MSN nanoparticles throughout the entire respiratory tract, including nasal, tracheobronchial and pulmonary regions using a water-based aerosol. This delivery method was successfully tested in mice by inhalation. The MSN nanoparticles used have the potential for carrying and delivering therapeutic agents to highly specific target sites of the respiratory tract. The approach provides a critical foundation for developing therapeutic treatment protocols for a wide range of diseases where aerosol delivery to the respiratory system would be desirable. Copyright © 2015. Published by Elsevier Inc.
    Nanomedicine: nanotechnology, biology, and medicine 03/2015; DOI:10.1016/j.nano.2015.03.007 · 5.98 Impact Factor
  • 01/2013; DOI:10.7763/IJBBB.2013.V3.179
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    ABSTRACT: Skin photoageing is a complex, multifactorial process and both intrinsic and extrinsic factors may contribute to its pathogenesis. The ultraviolet-irradiated hairless mouse has been used as an animal model for photoageing, but this model mimics only the 'extrinsic' aspects. Here, we show that skin from old SAMP1 mice, a model for higher oxidative stress and senescence acceleration, exhibited histological and gene expression changes similar to those in human photoaged skin without ultraviolet irradiation. These changes include an increase in elastic fibre and glycosaminoglycan histologically, an upregulation of several proinflammatory cytokines and matrix metalloproteinases, and an increase in lipid peroxide. We propose that SAMP1 mice are a spontaneous animal model for photoageing caused by an exaggerated intrinsic mechanism, namely, higher oxidative status. This mouse model is useful to explore the link between oxidative stress and photoageing, and to evaluate the efficacy of antioxidants.
    Experimental Dermatology 01/2013; 22(1):62-4. DOI:10.1111/exd.12059 · 4.12 Impact Factor
  • American Thoracic Society 2012 International Conference, May 18-23, 2012 • San Francisco, California; 05/2012
  • American Thoracic Society 2012 International Conference, May 18-23, 2012 • San Francisco, California; 05/2012
  • American Thoracic Society 2011 International Conference, May 13-18, 2011 • Denver Colorado; 05/2011
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    ABSTRACT: The emergence of drug-resistant microorganisms is an important medical and social problem. Drug-resistant microorganisms are thought to grow selectively in the presence of antibiotics. Most clinically isolated drug-resistant microorganisms have mutations in the target genes for the drugs. While any of the many mutagens in the environment may cause such genetic mutations, no reports have yet described whether these mutagens can confer drug resistance to clinically important microorganisms. We investigated how environmental mutagens might be implicated in acquired resistance to antibiotics in clinically important microorganisms, which causes human diseases. We selected mutagens found in the environment, in cigarette smoke, or in drugs, and then exposed Pseudomonas aeruginosa to them. After exposure, the incidence of rifampicin- and ciprofloxacin-resistant P. aeruginosa strains markedly increased, and we found mutations in genes for the antibiotic-target molecule. These mutations were similar to those found in drug-resistant microorganisms isolated from clinical samples. Our findings show that environmental mutagens, and an anticancer drug, are capable of inducing drug-resistant P. aeruginosa similar to strains found in clinical settings.
    FEMS Microbiology Letters 04/2011; 317(2):109-16. DOI:10.1111/j.1574-6968.2011.02215.x · 2.72 Impact Factor
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    ABSTRACT: Interleukin-28B (IL-28B), also referred to as interferon-λ3, belongs to the type III interferon family. Earlier studies showed that IL-28B suppresses proliferation of some tumor cells in vitro. IL-28B gene transfection ex vivo also resulted in growth retardation of tumor cells in mice, through either direct antiproliferative action or induction of antitumor immunity. However, it has not been reported whether in vivo therapeutic administration of recombinant IL-28B can inhibit the growth of a pre-established tumor. Here, we found that repetitive subcutaneous administration of recombinant mouse IL-28B significantly induced tumor-specific cytotoxic T lymphocytes and augmented natural killer cytolytic activity, leading to moderate suppression of the growth of a murine head and neck squamous cell carcinoma (HNSCC) cell line that was completely resistant to the direct antiproliferative effect of IL-28B. Moreover, co-administration of recombinant mouse IL-28B and cisplatin (CDDP) more significantly inhibited in vivo growth of the tumor that had been established in syngenic mice and induced tumor-specific cytotoxic T lymphocytes. The CDDP treatment induced the expression of major histocompatibility complex class I and Fas molecules on the surface of HNSCC cells both in vitro and in vivo; this may be the mechanism underlying the synergistic tumor suppression activity of IL-28B and CDDP. Unlike type I interferon, IL-28B did not suppress growth of bone marrow cells in culture. Therefore, IL-28B may be useful as a tool for a novel multidisciplinary therapy against cancer, significantly potentiating innate and adaptive antitumor immune responses, especially when co-administrated with CDDP, which is currently the first choice chemotherapeutic agent against various tumors including HNSCCs.
    Journal of immunotherapy (Hagerstown, Md.: 1997) 03/2011; 34(2):139-48. DOI:10.1097/CJI.0b013e318204ed70 · 3.35 Impact Factor
  • American Thoracic Society 2010 International Conference, May 14-19, 2010 • New Orleans; 05/2010
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    ABSTRACT: Exposure to cigarette smoke impairs the pulmonary immune system, including alveolar macrophage function, although the mechanisms by which this occurs are not fully elucidated. This study investigates the effect of cigarette smoke exposure on the antigen-presenting activity of alveolar macrophages, which is required for antigen-specific response to T cells. C57BL/6 mice were exposed to cigarette smoke for 10 days using a Hamburg II smoking machine, and alveolar macrophages were obtained by bronchoalveolar lavage. The antigen-presenting activity of alveolar macrophages was significantly inhibited in mice exposed to cigarette smoke compared with mice not exposed to cigarette smoke. Major histocompatibility complex class II cell surface molecule-positive cells, B7-1 molecule-positive cells, and interleukin-1beta messenger RNA gene expression in alveolar macrophages were significantly decreased in mice exposed to cigarette smoke compared with mice not exposed to cigarette smoke. In contrast, DNA damage and generation of superoxide and hydrogen peroxide in alveolar macrophages were significantly increased by cigarette smoke exposure. These results suggest that inhibition of the antigen-presenting activity of alveolar macrophages may result from decreased expression of major histocompatibility complex class II and B7-1 molecules and interleukin-1beta messenger RNA gene expression following cigarette smoke exposure. Furthermore, inhibition of antigen presentation in alveolar macrophage may result from DNA damage induced by excessive amounts of reactive oxygen species being generated by alveolar macrophages following cigarette smoke exposure. These findings suggest that cigarette smoke impairs the immunological function of alveolar macrophages and, as a result, increases the risk for pulmonary infection.
    Inhalation Toxicology 12/2009; 21(14):1229-35. DOI:10.3109/08958370903176727 · 2.34 Impact Factor
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    ABSTRACT: Dehydroepiandrosterone (DHEA), a reversible inhibitor of glucose-6-phosphate dehydrogenase (G6PD), is increasingly taken as an antioxidative and anti-ageing supplement. This study investigated the effects of DHEA on the expression of G6PD and on the state of oxidative stress in a human promyelocytic leukaemia cell line, HL60, during the differentiation to neutrophil-like cell. This study differentiated HL60 with dimethyl sulfoxide (DMSO) in the presence (DMSO-HL60/DHEA) or absence (DMSO-HL60) of DHEA. During the differentiation, activity, mRNA and protein levels of G6PD were increased. DHEA increased these levels further. DHEA by itself suppressed the production of superoxide from DMSO-HL60 upon stimulation with phorbol myristate acetate (PMA). However, DMSO-HL60/DHEA stimulated with PMA in the absence of DHEA produced superoxide and 8-oxo-deoxyguanosine more than PMA-stimulated DMSO-HL60. After addition of H(2)O(2), the ratio of reduced glutathione to oxidized glutathione was lower in DMSO-HL60/DHEA than in DMSO-HL60. These findings indicate that DHEA acts both as an antioxidant and as a pro-oxidant.
    Free Radical Research 09/2009; 43(10):922-31. DOI:10.1080/10715760903137093 · 2.99 Impact Factor
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    ABSTRACT: Jungle honey (JH) is collected from timber and blossom by wild honey bees that live in the tropical forest of Nigeria. JH is used as a traditional medicine for colds, skin inflammation and burn wounds as well as general health care. However, the effects of JH on immune functions are not clearly known. Therefore, we investigated the effects of JH on immune functions and antitumor activity in mice. Female C57BL/6 mice were injected with JH (1 mg/mouse/day, seven times intra-peritoneal). After seven injections, peritoneal cells (PC) were obtained. Antitumor activity was assessed by growth of Lewis Lung Carcinoma/2 (LL/2) cells. PC numbers were increased in JH-injected mice compared to control mice. In Dot Plot analysis by FACS, a new cell population appeared in JH-injected mice. The percent of Gr-1 surface antigen and the intensity of Gr-1 antigen expression of PC were increased in JH-injected mice. The new cell population was neutrophils. JH possessed chemotactic activity for neutrophils. Tumor incidence and weight were decreased in JH-injected mice. The ratio of reactive oxygen species (ROS) producing cells was increased in JH-injected mice. The effective component in JH was fractionized by gel filtration using HPLC and had an approximate molecular weight (MW) of 261. These results suggest that neutrophils induced by JH possess potent antitumor activity mediated by ROS and the effective immune component of JH is substrate of MW 261.
    Evidence-based Complementary and Alternative Medicine 02/2009; 2011:908743. DOI:10.1093/ecam/nen086 · 2.18 Impact Factor
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    ABSTRACT: Common laboratory rats and mice fail to develop persistent, progressive pulmonary inflammation found in chronic obstructive pulmonary disease as a result of tobacco smoke exposure. We hypothesized that spontaneously hypertensive rats would be more susceptible than normal Wistar Kyoto rats to acute tobacco smoke-induced pulmonary inflammation due to impaired apoptosis. Spontaneously hypertensive rats display systemic oxidative stress, inflammation, hypercoagulation, and immunosupression, similar to humans with chronic obstructive pulmonary disease. Male spontaneously hypertensive rats and Wistar Kyoto rats were exposed whole-body to tobacco smoke (total particulate concentration 75-85 mg/m(3)) or filtered air for 6 h/day for 2 or 15 days (3 days/wk). Tobacco smoke caused an increase in bronchoalveolar lavage fluid neutrophils at both time points in each strain. Significantly more neutrophils were noted in spontaneously hypertensive rats at 15 days compared to Wistar Kyoto rats. There was a trend of increase for macrophages in spontaneously hypertensive rats at both time points (significant at 2 days). TUNEL assay detected apoptotic cells in bronchoalveolar lavage fluid and lung tissue sections. The number of apoptotic neutrophils in airway walls and bronchoalveolar lavage fluid increased at 2 days in both strains, but at 15 days the effect was much lower in spontaneously hypertensive rats than in Wistar Kyoto rats. Tobacco smoke induces a greater inflammatory response associated with lower apoptotic neutrophils in the lungs of spontaneously hypertensive rats compared to Wistar Kyoto rats. The spontaneously hypertensive rat may be a more relevant animal model of acute tobacco smoke-induced airway inflammation than other laboratory rats.
    Inhalation Toxicology 06/2008; 20(7):623-33. DOI:10.1080/08958370701861538 · 2.34 Impact Factor
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    ABSTRACT: Bronchoalveolar lavage (BAL) is useful for diagnosing various interstitial lung diseases (ILDs) and monitoring ILD during treatment. The ability to detect specific agents or substances by using BAL is especially helpful in determining whether idiopathic ILD has a background causality. BAL in combination with other intensive examinations may enable the definitive diagnosis of an idiopathic ILD. Among the idiopathic ILDs of concern, this article focuses on idiopathic interstitial pneumonia (IIP) and cryptogenic organizing pneumonia (COP). IIP and COP are classified together as idiopathic interstitial pneumonia (IIP), an integrated clinicoradiographic pathological disease entity. BAL has identified two points important for differentiating the disease entity: a paucity of lymphocytes appears in the BAL fluid of patients with idiopathic pulmonary fibrosis (IPF), and lymphocytosis with a decreased CD4:CD8 ratio appears in patients with COP. These findings can be useful, in combination with high-resolution computed tomographic (HRCT) data, for selecting a favorable treatment option. On the other hand, these rules cannot be applied to IP associated with collagen vascular disease (CVD). Furthermore, some IIP patients may manifest features of CVD during the clinical course after the detection of IP (interstitial pneumonia). Thus the definite role of BAL cell profiles remains to be determined.
    Seminars in Respiratory and Critical Care Medicine 11/2007; 28(5):496-503. DOI:10.1055/s-2007-991522 · 3.02 Impact Factor
  • World Allergy Organization Journal 01/2007; DOI:10.1097/01.WOX.0000301637.48402.53
  • World Allergy Organization Journal 01/2007; DOI:10.1097/01.WOX.0000301631.10284.d1
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    ABSTRACT: Dichlorofluorescin (DCFH), a widely used fluorescent probe for reactive oxygen species (ROS) was decomposed completely and generated two distinct fluorescent products by photo-irradiation at 254 nm for 30 min. In the previous study, we had shown that one was dichlorofluorescein (DCF), a well known oxidized product of DCFH. In this study we investigated the other product and identified it as monochlorofluorescein (MCF) by 1H-NMR and fast atom bombardment/mass spectrum (FAB/MS) analyses. MCF was generated by photo-irradiation, but not by ROS. On the other hand, DCF was produced by both photo-irradiation and ROS. MCF showed similar fluorescent emission spectrum to DCF, however, its fluorescence intensity was more than that of DCF. The kinetic study suggested that MCF was not generated from DCF but from monochlorofluorescin, which might be generated from DCFH by photo-irradiation.
    Free Radical Research 10/2006; 40(9):959-65. DOI:10.1080/10715760600827012 · 2.99 Impact Factor
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    ABSTRACT: The study aims at establishing a novel vaccine procedure, using bone marrow-derived DCs that have ingested apoptotic B16 melanoma (DCs(+)), alone or in combination with splenic T lymphocytes from a syngenic donor. Co-immunization with DCs(+) and T cells showed the highest antitumor potential against preestablished B16 tumor in mice, in which CTL and NK cytotoxicities were drastically elevated, while either DCs(+) alone, naive DCs (DCs(-)) alone, or a mixture of DCs(-) and T cells induced less significant therapeutic outcomes. Use of extracellular matrix proteins elevated antitumor activity of DC(-)/T cell vaccine. Compared with the CD8(+) cells, the CD4(+)T cells more remarkably improved the efficacy of DC-based immunotherapy. The present system may be a feasible therapeutic modality to eradicate malignancies including melanoma.
    Cancer Letters 09/2006; 240(1):83-93. DOI:10.1016/j.canlet.2005.08.030 · 5.02 Impact Factor
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    ABSTRACT: Background Interleukin-21 (IL-21) plays important roles in the regulation of T, B, and natural killer (NK) cells. We hypothesized that the cytokine may provide a novel immunotherapy strategy for cancer by stimulating both Th1 and Th2 immune responses. In this context, antitumor immunity induced by IL-21 was examined in mice bearing subcutaneous head and neck squamous cell carcinomas (HNSCC).MethodsA plasmid vector encoding murine IL-21 was injected intravenously into mice with pre-established HNSCC tumors, either alone or in combination with a vector construct expressing IL-15. Cytotoxic T lymphocyte (CTL) and NK killing activities were evaluated by chrome release assays, while HNSCC-specific antibody was examined by flow cytometry and ELISA.ResultsSignificant antitumor effects were obtained by repeated transfection with either the IL-21 or the IL-15 gene. Co-administration of both cytokine genes resulted in increased suppression of tumor growth, significantly prolonging the survival periods of the animals. Thirty percent of the tumor-bearing mice that received the combination therapy survived for more than 300 days, completely rejecting rechallenge with the tumor at a distant site. IL-21 induced significant elevation of HNSCC-specific CTL activity, while IL-21 and IL-15 augmented NK activity in an additive manner. IL-21 gene transfer also promoted the production of tumor-specific IgG.Conclusions In vivo transduction of the IL-21 gene elicits powerful antitumor immunity, including both humoral and cellular arms of the immune response, and results in significant suppression of pre-established HNSCC. Co-transfer of the IL-15 gene further improved the therapeutic outcome, mainly by augmenting NK tumoricidal activity. The biological effects of IL-21 may be in sharp contrast to those of conventional Th1 and Th2 cytokines, suggesting intriguing implications of this cytokine for the classical concept of Th1 vs. Th2 paradigm. Copyright © 2005 John Wiley & Sons, Ltd.
    The Journal of Gene Medicine 01/2006; 8(1):90 - 99. DOI:10.1002/jgm.817 · 1.95 Impact Factor
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    ABSTRACT: Previous studies have shown that there is an association between low BALF (bronchoalveolar lavage fluid) CD4/CD8 ratio and lower remission rates in sarcoidosis patients. To investigate the patient characteristics and clinical features of Japanese sarcoidosis patients with low BALF CD4/CD8 ratios. 322 Japanese sarcoidosis patients were retrospectively analyzed, and 3 groups were selected according to BALF CD4/CD8 ratios as follows: patients with the BALF CD4/CD8 ratio in the lowest 5 percentile (Group 1: 0.43-1.41), median 5 percentile (Group II: 4.68-5.47), and top 5 percentile (Group III: 12.6-60.1). Each group consisted of 16 patients (5% of 322 patients). The patient characteristics, clinical features, and the short-term prognosis for at least 2 years (average 116 months) were compared among the groups. Multivariate analysis was performed for 322 patients to investigate the determinants of BALF CD4/CD8 ratios. The number of BALF CD8+ cells were greater in Group I than in the other two groups. In Group I, there were higher incidences of younger age, male gender, and lower number of extrathoracic lesions compared with Group III. Multivariate analysis showed that younger age and male gender were independently associated with low BALF CD4/CD8 ratios. The frequency of treatment with corticosteroid and progression to pulmonary fibrosis tended to be higher in Group I. Low BALF CD4/CD8 ratios were due to increased number of BALF CD8+ cells. Younger age and male gender were independently associated with low BALF CD4/CD8 ratios in sarcoidosis patients.
    Sarcoidosis, vasculitis, and diffuse lung diseases: official journal of WASOG / World Association of Sarcoidosis and Other Granulomatous Disorders 07/2005; 22(2):154-60. · 1.74 Impact Factor