Enhanced optical and nonlinear optical responses in a polyelectrolyte templated Langmuir-Blodgett film.

Optical and nonlinear optical properties like fluorescence and second harmonic generation (SHG) of molecular materials can be strongly influenced by the mode of assembly of the molecules. The Langmuir-Blodgett (LB) technique is an elegant route to the controlled assembly of molecules in ultrathin films, and complexation of ionic amphiphiles in the Langmuir film by polyions introduced in the aqueous subphase provides a simple and efficient access to further control, stabilization, and optimization. The monolayer LB film of the hemicyanine-based amphiphile, N-n-octadecyl-4-[2-(4-(N,N-ethyloctadecylamino)phenyl)ethenyl]pyridinium possessing a "tail-head-tail" structure, shows fluorescence as well as SHG response. The concomitant enhancement of both of these linear and nonlinear optical attributes is achieved through templating with the polyanion of carboxymethylcellulose. Brewster angle and atomic force microscopy reveal the influence of polyelectrolyte templating on the morphology of the Langmuir and LB films. Polarized absorption and fluorescence spectroscopy provide insight into the impact of complexation with the polyelectrolyte on the orientation and deaggregation of the hemicyanine headgroup leading to fluorescence and SHG enhancement in the LB film.

Immunohistochemical studies on the distribution of lymphocytes in the peripheral and mucosal lymphoid tissues of laboratory musk shrews (Suncus murinus).

We developed a new monoclonal antibody (mAb), named 1E9, which recognizes the immunoglobulin (Ig) M-like molecule of the insectivore laboratory animal, the suncus. This mAb was developed in order to investigate the distribution of surface Ig (sIg)-bearing lymphocytes in the lymphoid tissues of this animal. Immunohistochemically, the distribution of 1E9+ lymphocytes in the follicles of peripheral lymphoid tissues showed homology with such distribution in rodents. However, the lymphocytes in the follicles of the mucosal lymphoid tissues were not recognized by the mAb. These data suggest that from a comparative immunological viewpoint, our newly developed 1E9 mAb is useful for the characterization of sIg+ lymphocytes in the peripheral and mucosal lymphoid tissues of the suncus.

Novel approach to photonic bands with frequency-dependent dielectric constants.

We formulated a novel method to calculate the dispersion relations of arbitrary photonic crystals with frequency-dependent dielectric constants based on the numerical simulation of dipole radiation. As an example, we applied this method to a two-dimensional square lattice of metallic cylinders and obtained a good agreement with the previous result by means of the plane-wave expansion method by Kuzmiak et al. [Phys. Rev. B 50, 16 835 (1994)]. In addition to the dispersion relations, we could obtain the symmetries and the wave functions of the eigenmodes.

Reduction of platelet phospholipase C-delta1 activity in Alzheimer's disease associated with a specific apolipoprotein E genotype (epsilon3/epsilon3).

The epsilon4 allele of apolipoprotein E (apo E) is increased among patients with sporadic or familial Alzheimer's disease (AD). We examined platelet phospholipase C (PLC)-delta1 activity in AD patients either homozygous for apoepsilon3 or having at least one apo epsilon4 allele. We found that platelet PLC-delta1 activity is reduced from control levels in patients homozygous for apo epsilon3, but not changed in patients with an apo epilson4 allele. Reduced PLC-delta1 activity and apo epsilon3 may contribute to AD pathogenesis apart from the apo epsilon4 allele.

Suppression of the DTH reaction in mice by means of moxibustion at electro-permeable points.

The effects of moxibustion stimulation on picryl chloride-induced cutaneous contact hypersensitivity, a delayed type of hypersensitivity (DTH) reaction, were investigated in mice. Three electro-permeable points (B-20, LI-15, S-36) were selected as moxibustion points. Moxibustion at point B-20 (spleen associated point) significantly suppressed the DTH reaction. Adoptive transfer of spleen T cells from moxibustion-stimulated donors resulted in an increased suppression of the DTH reaction in the recipients. These studies suggest that suppression of the DTH reaction with moxibustion may be related to cellular immunity, especially to the induction of the suppressive activity of T cells in the spleen.