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Hiroshima-shi, Japan

Bower J.,Hiroshima Bunkyo Womens University | Kawaguchi S.,University of Western Sydney
Language Learning and Technology | Year: 2011

This paper presents a comparative analysis of corrective feedback provided by participants in an eTandem interaction between university students in Japan and Australia who were learning each other's language. Corrective feedback provided to tandem partners during interaction via text-based Synchronous Computer Mediated Communication (SCMC) is compared to corrective feedback provided to tandem partners post-chat utilizing logs of the chat interaction. Results show that implicit corrective feedback on NNS errors occurred in the text-based SCMC interaction but not frequently. On the other hand, negotiation of meaning occurred most often to overcome communication problems during chat exchange rather than in direct relation to errors. This is a crucial element for L2 development since the learner finds himself/herself in the sort of context that allows for recognition of developmental gaps. Further, explicit corrective feedback utilizing conversation logs and exchanged by email achieved high rates of correction both in English and Japanese sessions. The strategy of sending post-chat corrective feedback is shown to be an effective eTandem language learning strategy providing learners with opportunities to focus on form in their L2. © 2011.

Morioke S.,Hiroshima University | Hiragun T.,Hiroshima University | Yanase Y.,Hiroshima University | Uchida K.,Hiroshima University | And 4 more authors.
Journal of Investigational Allergology and Clinical Immunology | Year: 2012

Background: Immunoglobulin (Ig) E plays an important role in the pathogenesis of allergic diseases such as atopic dermatitis and allergic asthma. We previously reported that a sulfate polysaccharide, fucoidan, suppressed IgE production by murine B cells in vitro. However, the mechanism by which fucoidan suppresses IgE production remains unclear. Objective: We incorporated sulfate groups into cellulose and studied their biological characteristics in vitro to explore the possibility of converting biologically neutral polysaccharides to active reagents with antiallergic functions. Material and Methods: Cellulose was chemically processed using N,N-dimethylformamide (DMF) and DMF-sulfurtrioxide and recovered as cellulose sulfate with a molecular weight of around 10 kDa. We then studied the effect of cellulose sulfate on IgE production from B cells, IgE class-switching, and populations of IgE-secreting B cells prepared from murine spleen. We also investigated the effects of sulfated cellulose on the production of interleukin (IL) 4 and interferon (IFN) γ and the expression of T-bet mRNA by splenic T cells. The cytotoxicity of cellulose sulfate was also examined. Results: Cellulose sulfate suppressed IgE production in B cells stimulated with IL-4 and anti-CD40 antibody by inhibiting IgE class-switch recombination and decreasing the number of IgE-secreting B cells in vitro. Moreover, both cellulose sulfate and fucoidan suppressed IL-4 production and enhanced IFN-γ production by murine T cells stimulated with anti-CD3 and anti-CD28 antibodies, despite the decrease in T-bet mRNA expression. Conclusions: Cellulose gains an antiallergic effect on B cells and T cells with the addition of sulfate groups. © 2012 Esmon Publicidad.

Shimosaki S.,The University of Shimane | Tsurunaga Y.,Hiroshima Bunkyo Womens University | Itamura H.,The University of Shimane | Nakamura M.,The University of Shimane
Natural Product Research | Year: 2011

Flavonoids are ingested by the general population as anti-oxidant and anti-inflammatory agents. In this study, we investigated the effects of myricitrin, a flavonoid rich in Myrica rubra leaf, upon anti-inflammatory action. Myrica rubra leaf extracts inhibited pro-inflammatory TNFα production in a macrophage cell line, Raw264.7 cells. We observed that the serum IgE levels in the leaf extract-treated DO11.10, a mouse allergy model, were down-regulated. HPLC was performed to demonstrate that M. rubra leaf extracts contain a large amount of myricitrin. We observed an inhibitory effect of HPLC-purified myricitrin on TNFα production in Raw264.7 cells. Thus, myricitrin may be of potential interest in the management of inflammatory conditions. © 2011 Taylor & Francis.

Hiragun T.,Hiroshima University | Ishii K.,Hiroshima University | Hiragun M.,Hiroshima University | Suzuki H.,Hiroshima University | And 7 more authors.
Journal of Allergy and Clinical Immunology | Year: 2013

Background: Sweat is a major aggravating factor of atopic dermatitis (AD) and approximately 80% of patients with AD show type I hypersensitivity against sweat. Objective: To identify and characterize an antigen in sweat that induces histamine release from basophils of patients with AD. Methods: Basophil histamine-releasing activity in sweat was purified by a combination of chromatographies, and proteins were analyzed with mass spectrometry. Recombinant proteins of the sweat antigen were generated, and their biological characteristics were studied by immunoblots, histamine release tests, and neutralization assays. Results: We identified a fungal protein, MGL-1304, derived from Malassezia globosa (M globosa) in the purified sweat antigen. Recombinant MGL-1304 induced histamine release from basophils of most of the patients with AD, in accordance with the semi-purified sweat antigen. Moreover, recombinant MGL-1304 abolished the binding of serum IgE of patients with AD to the semi-purified sweat antigen, or vice versa in immunoblot analysis, and attenuated the sensitization of RBL-48 mast cells expressing human FcÉRI by serum IgE. Studies of truncated mutants of MGL-1304 indicated that IgE of patients with AD recognized the conformational structure of MGL-1304 rather than short peptide sequences. Western blot analysis of the whole lysate, the culture supernatant of M globosa, and the semi-purified sweat antigen showed that MGL-1304 was produced as a minor immunological antigen of M globosa with posttranslational modification, cleaved, and secreted as a 17-kDa major histamine-releasing sweat antigen. Conclusion: MGL-1304 is a major allergen in human sweat and could cause type I allergy in patients with AD. © 2013 American Academy of Allergy, Asthma & Immunology.

Tsurunaga Y.,Hiroshima Bunkyo Womens University | Matsumoto S.,The University of Shimane
Acta Horticulturae | Year: 2010

Persimmon (Diospyros kaki Thunb.) leaves, calyxes, and branches have been used in Chinese medicine to treat hiccups and coughing. Because of the high levels of ascorbic acid and polyphenols in persimmon leaves, its consumption as a tea and in health foods is increasing in Japan. The manufacturing process has significant effects on ascorbic acid and polyphenol contents in persimmon leaf tea. We developed a manufacturing process for persimmon leaf tea that retains high levels of ascorbic acid, polyphenols, and radical scavenging activity. We used persimmon leaves collected during May from 14-year-old trees in a 'Saijo' Japanese persimmon orchard. The raw persimmon leaves were washed with tap water and spin-dried to remove surface water. The leaves were divided into approximately 300 g lots and then steamed for 0, 1, 5, 10, or 20 min. After steam treatment, persimmon leaves were air-dried for 12 h at 60°C in a spontaneous convection oven. We measured ascorbic acid, polyphenols, and 1,1-diphenyl1-2-picrylhydrazyl (DPPH) radical scavenging activity in persimmon leaf tea immediately after manufacturing and after storage for one year at room temperature. Immediately after manufacturing, the levels of ascorbic acid, polyphenols, and DPPH radical scavenging activity in non-steamed tea were 3,300 mg/100 g DW, 8,500 mg catechin eq./100 g DW and 510 μmol Trolox eq./g DW respectively; after storage for one year they were 0 mg/100 g DW, 5,250 mg catechin eq./100 g DW and 370 μmol Trolox eq./g DW, respectively. Immediately after manufacturing, the levels in leaves that were steamed for 5 min were 4,700 mg/100 g DW, 9,300 mg catechin eq./100 g DW and 530 μmol Trolox eq./g DW, respectively; after storage for one year, these levels were 3,000 mg/100 g DW, 6,560 mg catechin eq./100 g DW, and 450 μmol Trolox eq./g DW, respectively. Our results show that a 5 min steam treatment during the manufacturing process produces persimmon leaf tea that retains high levels of ascorbic acid, polyphenols, and DPPH radical scavenging activity, even after storage for one year.

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