[Liposome modified with VIP-lipopeptide as a new drug delivery system].

We have designed a novel lipid analog (lipopeptide) that mimics the structural features of modified phospholipids. This lipopeptide is easily synthesized using a peptide synthesizer and has been shown to be useful for the modification of liposomes, which are used as an active targeted drug delivery system (DDS). Vasoactive intestinal peptide (VIP) has high homology with pituitary adenylate cyclase activating peptide (PACAP). There are three major PACAP receptors: PAC1R, VPAC1R, and VPAC2R. PAC1R has affinity only for PACAP, whereas VPAC1R and VPAC2R have the same affinity for both VIP and PACAP. In the present study, we synthesized several lipopeptides conjugated with VIP through different linkers and found that liposomes modified with these lipopeptides (VIP-Lips) selectively recognized the PACAP/VIP receptors. The anti-cancer activity of these VIP-Lips was evaluated by encapsulation of an antitumor drug, doxorubicin (DOX), into the modified liposomes (VIP-Lips-DOX) against the human osteosarcoma cell line, Saos-2, which highly expresses the VIP receptor. cAMP production was then measured to determine how well the VIP-Lips were able to recognize VPAC2R. The results clearly indicate that the proposed lipopeptide methodology holds promise as a DDS for cancer therapy.

Synthesis of VIP-lipopeptide using a new linker to modify liposomes: towards the development of a drug delivery system for active targeting.

A new component for the solid phase peptide synthesis of lipopeptide, 2-[(4R,5R)-5-({[(9H-fluoren-9-yl)methoxy]carbonylaminomethyl}-2,2-dimethyl-1,3-dioxolan-4-yl)methoxy]acetic acid (2), was designed and synthesized from (-)-2,3-O-isopropylidene-D-threitol (3) in 4 steps. The key step was the selective alkylation of 3 with benzyl bromoacetate in the presence of Cs2CO3. Vasoactive intestinal peptide (VIP)-lipopeptide (1) incorporating this linker was synthesized by solid phase peptide synthesis.

Delayed optical images through coupled-resonator-induced transparency.

We propagated transverse two-dimensional images encoded on optical pulses through a frequency window of a coupled-image-resonator-induced transparency. The optical images are stored and delayed by 10.6ns, reflecting the tunable dispersion of the coupled resonator. The k-space bandwidth of the amplitude transfer function of the system is discussed in the presence of the off-resonance Fano interference effect between the two resonators.

Advanced and delayed images through an image resonator.

We performed optical image propagation experiments in an image resonator consisting of a Fabry-Perot resonator in reflection geometry. Two-dimensional images encoded on optical pulses of 32ns were stored, and either advanced, -6.0ns, or delayed, 10.9ns, using the dispersion relation relevant to the image resonator, in the under- or over- coupling condition, respectively. The overall images are propagated through the resonator clearly, while the diffraction effects were analyzed both in real-space and in k-space.

[Nonmyeloablative allogeneic peripheral blood stem cell transplantation of renal cell carcinoma].

We presented three cases with refractory metastatic renal cell carcinomas who underwent nonmyeloablative allogeneic peripheral blood stem cell transplantation(PBSCT). A fludarabine and cyclophosphamide-based regimen was used. Complete donor-T-cell chimerism was established at day 94, 40, 52 after PBSCT in each case. GVHD occurred at day 183, 53, 75. In Case 1 and Case 3 apparent GVT effects reduced the metastases at day 212, 261 and let them live longer than expected. Case 2 died at day 69 before GVT effect appeared, because the case was so-called rapid growth type. Histological examinations in Case 1 and Case 3 showed infiltration of lymphocytes disrupting the foci of renal cell carcinomas which was considered as findings of GVT effects.