Bio-based polycarbonates containing cyclic ketal moieties were designed, and the bio-based diol monomer was synthesized by CQ with glycerol to improve their thermal properties and replace BPA in polymer industry. The molecular structure of the novel bio-based diol monomer 2,2:3,3-bis(4′-hydroxymethylethylenedioxy)-1,7,7-trimethylbicyclo[2.2.1]heptane (abbreviated as CaG) was analyzed by 1 H, 13 C, and 2D-COSY NMR techniques. GPC results show that CaG was reacted successfully and led to the high molecular weights for homopolycarbonate (M w = 18 652) abbreviated as PCaGC and for copolycarbonate (M w = 78 482) as PCaG 20 BPA 80 C. The high thermal stability (T d value above 350°C) and glass transition temperature (T g value from 128 to 151°C) of PCaGCs and PCaG x BPA y Cs were studied by TGA and DSC, respectively. Given the sufficient reactivity and high thermal stability, CaG is a promising renewable building block for applicable polymers.

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Bone morphogenetic proteins (BMPs) belong to the transforming growth factor (TGF-b) superfamily and are involved in osteoblastic differentiation. The largest TGF-b superfamily subgroup shares genetic homology with human BMPs (hBMPs) and silkworm decapentaplegic (dpp). In addition, hBMPs are functionally interchangeable with Drosophila dpp . Bombyx mori dpp may induce bone formation in mammalian cells. To test this hypothesis, we synthesized the 1,285-base pairs cDNA of full-length B. mori dpp using total RNAs obtained from the fat body of 3-day-old of the 5 th instar larvae and cloned the cDNA into the pCEP4 mammalian expression vector. Next, B. mori dpp was expressed in C3H10T1/2 cells. The target cells transfected with the pCEP4-Bm dpp plasmid showed biological functions similar to those of osteogenic differentiation induction growth factors such as hBMPs. We determined the relative mRNA expression rates of Runt-related transcription factor 2 (RUNX2), osterix, osteocalcin, and alkaline phosphatase (ALP) to validate the osteoblast-specific differentiation effects of B. mori dpp by performing quantitative real-time RT-PCR. Interestingly, mRNA expression levels of the 3 marker genes except RUNX2, in cells expressing B. mori dpp were much higher than those in control cells and C3H10T1/2 cells transfected with pCEP4. These results suggested that B. mori dpp signaling regulates osterix expression during osteogenic differentiation via RUNX2-independent mechanisms.