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Narrowband-ultraviolet B (NB-UVB) phototherapy is used for the treatment of atopic dermatitis. Previously, we reported that irradiation with 200 mJ/cm2of 310 nm NB-UVB suppressed phorbol-12-myristate-13-acetate (PMA)-induced up-regulation of histamine H1receptor (H1R) gene expression without induction of apoptosis in HeLa cells. However, the effect of NB-UVB irradiation on nasal symptoms is still unclear. Here, we show that low dose irradiation with 310 nm NB-UVB alleviates nasal symptoms in toluene 2,4-diisocyanate (TDI)-sensitized allergy model rats. Irradiation with 310 nm NB-UVB suppressed PMA-induced H1R mRNA up-regulation in HeLa cells dose-dependently at doses of 75–200 mJ/cm2and reversibly at a dose of 150 mJ/cm2without induction of apoptosis. While, at doses of more than 200 mJ/cm2, irradiation with 310 nm NB-UVB induced apoptosis. Western blot analysis showed that the suppressive effect of NB-UVB irradiation on H1R gene expression was through the inhibition of ERK phosphorylation. In TDI-sensitized rat, intranasal irradiation with 310 nm NB-UVB at an estimated dose of 100 mJ/cm2once a day for three days suppressed TDI-induced sneezes and up-regulation of H1R mRNA in nasal mucosa without induction of apoptosis. These findings suggest that repeated intranasal irradiation with low dose of NB-UVB could be clinically used as phototherapy of AR.

Static and dynamic light scattering and viscosity measurements were made on 12 samples of polymacromonomer F110 consisting of polystyrene with 113 styrene units in each side chain to determine the z-average mean-square radius of gyration, the hydrodynamic radius, and the intrinsic viscosity in cyclohexane at 34.5 °C (the theta temperature) and toluene at 15.0 °C as functions of weight-average molecular weight Mw. Small-angle X-ray scattering experiment was also performed for one sample in the two solvents. The dependence of the three measured properties on Mwin the range 1.9×105–1.3×107studied were consistently explained by available theories for the wormlike chain with ML(the molar mass per unit contour length) = 45500 nm-1, ?-1(the stiffness parameter) = 80 nm (in cyclohexane) or 155 nm (in toluene), and d (the chain diameter) = 16–26 nm (depending on the kind of solvent and measured property) when the end effect arising from side chains near the main-chain ends was taken into account. The side-chain length dependence of ?-1, examined with the aid of previous data for three polystyrene polymacromonomers with shorter side chains of 15, 33, and 65 styrene units, was found to be almost quantitatively explained by the theory of Nakamura and Norisuye [Polym. J., 33, 874 (2001)]. That of d was also discussed in relation to the end-to-end distance of a wormlike side chain.

Synchrotron small-angle X-ray scattering (SAXS) measurements have been made on toluene solutions of six polystyrene polymacromonomer samples having a fixed side chain length of 15 styrene residues and ranging in the polymerization degree of the main chain Nwfrom 6.5 to 106 (in weight average) at 25 °C. The z-average mean-square radii of gyration zfrom the present SAXS and previous light scattering as a function of Nwand the particle scattering functions P(?) in the form of k2P(?) against k (the magnitude of the scattering vector) are compared with theoretical values for three models: (a) the wormlike cylinder with a uniform cross section, (b) the wormlike chain with Gaussian density distribution within the cross-sectional plain, and (c) the touched-bead comb with wormlike main and side chains. Theoretical curves for the models (a) and (b) equally fit the data points for zand k2P(?) (for k<1nm-1) with a set of model parameters consistent with that describing the previously determined Nw-dependence of intrinsic viscosity in toluene, but the latter model explains the P(?) behavior up to a slightly larger k. The model (c) allows similarly good fits to zand better fits to k2P(?) over a wider k range if the Kuhn segment length of each side chain and the bead diameter are adjusted to values much larger than those expected for an isolated polystyrene molecule. The decoupling approximation to P(?) invoked in the literature is also examined for the models (a) and (b).