In this study, we have investigated the effect of surface treatment on the orientation and mobility of pentacene by using a photoreactive polyimide film to modify the gate-insulator surfaces of organic field effect transistors (OFETs). Surface modification includes a photoreactive polyimide film, presenting a passivated interface on which the semiconductor can grow. This polyimide film can control of the orientation of semiconductor by using linearly polarized deep UV (LPDUV) irradiation. Fabricated OFETs include stacked structures of Ta2O5 as the gate insulators and the photoreactive polyimide. Most of the characteristic parameters of the OFETs, such as carrier mobility and on/off current ration, have been improved by using the photo-alignment treatment achieved with LPDUV irradiation.

Oral administration of raffinose, a naturally occurring indigestible oligosaccharide, has reportedly ameliorated atopic dermatitis in human subjects although the mechanism is unknown. The present study investigated the effect of dietary raffinose on allergen-induced airway eosinophilia in ovalbumin-sensitised Brown Norway rats as an atopic disease model. Brown Norway rats were immunised by subcutaneous injection with ovalbumin on day 0 and fed either a control diet or the diet supplemented with raffinose (50 g/kg diet). The rats were exposed to aerosolised ovalbumin on day 20, and broncho-alveolar lavage fluid was obtained on the next day. The number of eosinophils in the fluid was significantly lower in the rats fed the raffinose diet than in those fed the control diet. Dietary raffinose significantly reduced IL-4 and IL-5 mRNA levels in lung tissue and tended to lower ovalbumin-specific Ig E levels. Suppression of eosinophilia by dietary raffinose was still observed in caecectomised and neomycin-administered rats, suggesting little contribution by the colonic bacteria to the effect of raffinose. Intraperitoneal administration of raffinose also suppressed eosinophilia. Significant concentrations of raffinose were detected in portal venous and abdominal arterial plasma after the intragastric administration of raffinose. Overall, the findings suggest that dietary raffinose ameliorates allergic airway eosinophilia at least partly via post-absorptive mechanisms in Brown Norway rats.

The effects of the dietary oligosaccharide raffinose on immune responses, with special reference to its anti-allergic functions, were examined in vivo. First, feeding a diet supplemented with 50 g raffinose/kg to BALB/c mice significantly (P<0·05) increased interleukin (IL) 12 secretion from isolated Peyer's patch (PP) cells in vitro compared with feeding control diet. When isolated PP cells were used as antigen-presenting cells (APC) for CD4+ T-splenocytes isolated from ovalbumin (OVA)-specific T-cell receptor transgenic (Tg) mice in the presence of OVA as antigen, significantly (P<0·05) higher levels of interferon-γ were observed in the cultures using APC from raffinose-fed mice than those cultures using APC from control mice. Second, the diet containing 50 g raffinose/kg or control diet was fed to OVA Tg mice, and subsequently, OVA was added to each diet to prime T cells in vivo. CD4+ T-cells from the mesenteric lymph nodes of the raffinose-fed mice secreted significantly (P<0·05) higher levels of IL-2 and significantly (P<0·05) lower levels of IL-4 following in vitro antigenic stimulation compared with those of the control mice. These present results suggest that feeding raffinose may suppress differentiation of naïve T-helper (Th) cells into Th2 cells in the mesenteric lymphoid nodes. Last, feeding raffinose suppressed rises of serum immunoglobulin E levels in the Tg mice treated with long-term ingestion of OVA. In conclusion, it is suggested that dietary raffinose suppresses serum immunoglobulin E response through suppression of Th2-type immune response against oral antigen in the lymphoid organs located in or near the intestine.