Quality control of tissues and organs for transplant is important to confirm their safety and effectiveness for regenerative medicine. However, quality evaluation is only carried out using a limited range of inspection criteria, because many of the available evaluation tests are invasive. In order to explore the potential of 2-[ 18 F]fluoro-2-deoxy-D-glucose ([ 18 F]FDG)-bioradiography as a non-invasive test for estimation of the safety, soundness, and effectiveness of tissues for transplantation, [ 18 F]FDG uptake and cell viability or metabolism were investigated using a reconstructed human epidermal model (RHEM). We developed an imaging system, and suitable bioradiographic image acquisition conditions and its effectiveness were investigated. [ 18 F]FDG uptake increased in agreement with DNA content as a marker of cell numbers and for histological assessment during cell proliferation and keratinization. [ 18 F]FDG uptake was significantly decreased in good agreement with the viability of tissues used with various hazardous chemical treatments. [ 18 F]FDG uptake by the tissues was decreased by hypothermia treatment and increased by hypoxia treatment while maintaining cell viability in the tissue. Therefore, [ 18 F]FDG-bioradiography can be useful to estimate cell viability or metabolism in this RHEM. This method might be utilized as a non-invasive test for quality evaluation of tissues for transplantation.

Dynamics of S = 1 antiferromagnetic bond-alternating chains in the dimer phase, in the vicinity of the critical point with the Haldane phase, is studied by a field theoretical method. This model is considered to represent the compound Ni(C9H24N4)(NO2)ClO4 (abbreviated as NTENP). We derive a sine-Gordon (SG) field theory as a low-energy effective model of this system, starting from a Tomonaga-Luttinger liquid at the critical point. Using the exact solution of the SG theory, we give a field theoretical picture of the low-energy excitation spectrum of NTENP. Results derived from our picture are in a good agreement with results of inelastic neutron scattering experiments on NTENP and numerical calculation of the dynamical structure factor. Furthermore, on the basis of the obtained theoretical picture, we predict that the sharp peaks correspond to a single elementary excitation are absent in the Raman scattering spectrum of NTENP in contrast to the inelastic neutron scattering spectrum.

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