It has been reported that resveratrol (trans-3,5,4Ј-trihydroxystilbene) from Vitis plants has various cardioprotective effects. Vitis plants also include various resveratrol tetramers. The aim of our study is to clarify the pharmacological properties of resveratrol tetramers. We isolated two resveratrol tetramers as major products of Vitis plants. One is vitisin A, a complex of two resveratrol dimers, (ϩ)--viniferin and ampelopsin B, and the other is hopeaphenol, composed of 2 mol ampelopsin B. Vitisin A (30 -300 nM) unexpectedly dose-dependently facilitated swelling and depolarization of mitochondria and cytochrome c release from mitochondria, which are indices of cardiomyocyte apoptosis. Furthermore, vitisin A induced apoptosis in the primary culture of adult rat ventricular myocytes. On the other hand, hopeaphenol (1-10 M) dose-dependently inhibited Ca 2ϩ (30 M)-induced mitochondrial depolarization and cytochrome c release from mitochondria but had not affected mitochondrial swelling. Moreover, hopeaphenol inhibited vitisin A-induced apoptosis. In structural and functional studies, we further confirmed that vitisin B, one of the resveratrol tetramers having (ϩ)--viniferin unit, induces mitochondrial swelling and cytochrome c release from mitochondria like vitisin A and that vitisifuran A, one of the resveratrol tetramers having the ampelopsin B unit, inhibits Ca 2ϩ -induced cytochrome c release from mitochondria like hopeaphenol. These results show that resveratrol tetramers have at least two opposite effects on cardiomyocytes; the one having the (ϩ)--viniferin unit induces cardiomyocyte apoptosis, and the other having ampelopsin B but not (ϩ)--viniferin unit inhibits it.

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We study a block type 3D printer that performs assembly of toy block from 3D CAD models. In this system, a 3D CAD model is automatically converted to a block model consisting of primitive shapes of toy blocks. Then a feasible assembly plan of the block model is also generated automatically. According to the assembly plan, an industrial robot assembles a block sculpture layer by layer from bottom to top. This approach has advantages in terms of reusability of materials and easiness of combining multiple materials, which are difficult for conventional 3D printers. We introduce a technique to determine the order of block placement to assemble various patterns of block models reliably. The technique includes converting unassemblable shapes in the model to assemblable ones with support blocks and/or decomposition into subassemblies. In addition to this, we implement a robot control system to automatically generate a desired sculpture stably according to the determined placement order. Experiments of assembling toy block models are demonstrated. The results show that our system can assemble various block models.

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