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As a kind of coleopteran insects, the unfolding and folding of ladybirds’ hind wings shows the natural superiority, which provides a new way for the design of space deployable structures (such as satellite solar wings, bionic wings, antennas, etc.). The equivalent simulation study based on the crease model of the ladybug’s hind wings by the origami found that the membrane part of the hind wings has local stress and deformation during the folding process, which increases the difficulty of the engineering design of the folding structures based on rigid panels. Based on the geometric constraint analysis of the crease model of the ladybug’s hind wings, this paper proposes a calculation method that can realize rigid foldability, which will provide a reference for the engineering application research of the space folding structures.

The triazine-based bisbinaphthyl crown ethers oxacalix[2]arene[2]bisbinaphthes R-1, R-2, R-3 and S-1, S-2, S-3 were synthesized. The interactions of these compounds with various α-aminocarboxylic acid anions were studied. The crown ethers were found to carry out highly enantioselective fluorescent recognition of α-aminocarboxylic acid anions. It is observed that within a certain concentration range, one enantiomer of the chiral α-aminocarboxylic acid anions can increase the fluorescence intensity of the crown ethers by fivefold to sixfold, whereas the other enantiomer scarcely enhances the fluorescence. Such unusually high enantioselective responses make these crown ethers very attractive as fluorescent sensors in determining the enantiomeric composition of α-aminocarboxylic acid anions. Chirality 24:646–651, 2012. © 2012 Wiley Periodicals, Inc.

As a consequence of cost-cutting changes, termed "TennCare reform," to Tennessee's state-funded health care plan, a number of beneficiaries have either had their benefits substantially reduced or have been disenrolled entirely. The purpose of this study was to determine the impact of these reforms on the health of patients with chronic rheumatic diseases.We determined differences with adherence to scheduled appointments in an urban academic rheumatology clinic in the 3 months before and in the 3 months after TennCare reform. A telephone survey was conducted to determine plans for future rheumatic care among those patients scheduled to be seen in this clinic in the 3 months after TennCare reform.Overall, 402 of the 601 patients scheduled for a rheumatology clinic appointment before TennCare reform (67%) adhered to their scheduled rheumatology appointment, compared with 362 of 595 patients (61%) scheduled for an appointment after TennCare reform, a difference that was statistically significant (P = 0.034). After TennCare reform, patients who did not adhere with clinic follow-up were more likely to have been disenrolled from TennCare (P0.001). By telephone survey, among those who were disenrolled from TennCare, almost half indicated that they did not know where they were going to receive future rheumatic disease care. Among those who retained TennCare, less than half indicated that they could afford to purchase all of their medications.TennCare reform has significantly limited care for patients with rheumatic diseases. The long-term consequences of this merit future study.

Bone morphogenetic protein 3 (BMP3) is a potent osteoinductive growth factor belonging to the TGF-beta superfamily. In this study, we engineered a recombinant BMP3 protein to include an auxiliary collagen-targeting domain derived from von Willebrand coagulation factor (vWF). The collagen-targeted BMP3 fusion protein (rhBMP3-C) was expressed in E. coli, purified from bacterial inclusion bodies, renatured under controlled redox conditions, and assayed for biological activity in vitro and in vivo. The renatured rhBMP3-C fusion protein bound tightly to collagen matrices and inhibited DNA synthesis in normal rat calvaria cells and in two out of three human osteosarcoma cell lines tested. Alkaline phosphatase activity was increased in rat calvarial cells and was decreased in osteosarcoma cells in vitro in a dose-dependent manner. Collagen sponges impregnated with rhBMP3-C and implanted subcutaneously in Fischer-344 rats induced dose-dependent dystrophic calcification of the collagen matrix, with no evidence of ectopic bone formation. However, local injection of rhBMP3-C infused in a collagen suspension induced new bone formation on the periosteal surface of rat calvaria. Finally, in a rat cranial defect model, surgical implantation of rhBMP3-C arrayed on either collagen sponges or on porous ceramics coated with Type I collagen exhibited marked osteoinductive properties. Taken together, these results demonstrate the feasibility of engineering and manufacturing targeted-BMPs which exhibit an integral gain-of-function that may be exploited to therapeutic advantage in (i) the enhancement of effective local concentrations, (ii) the prevention of systemic biodistribution and side effects, and (iii) the design of improved osteoinductive matrices.

The triazine-based bisbinaphthyl crown ethers oxacalix[2]arene[2]bisbinaphthes R-1, R-2, R-3 and S-1, S-2, S-3 were synthesized. The interactions of these compounds with various α-aminocarboxylic acid anions were studied. The crown ethers were found to carry out highly enantioselective fluorescent recognition of α-aminocarboxylic acid anions. It is observed that within a certain concentration range, one enantiomer of the chiral α-aminocarboxylic acid anions can increase the fluorescence intensity of the crown ethers by fivefold to sixfold, whereas the other enantiomer scarcely enhances the fluorescence. Such unusually high enantioselective responses make these crown ethers very attractive as fluorescent sensors in determining the enantiomeric composition of α-aminocarboxylic acid anions.

The osteoinductivity of demineralized bone matrix (DBM) becomes significantly reduced if the specimens are further delipidated with chloroform-methanol. The addition of phosphatidylcholine (PC), a major constituent of the lipid fraction present in the calcification front during normal bone formation, can restore the biological activity. Active endochondral bone formation is observed in the DBM/PC implants placed in the anterior abdominal wall musculature or subcutaneously for 28 days. When PC is added to generate a putty containing 60% PC and 40% DBM, biochemical parameters associated with osteoinductivity are significantly enhanced. Biological responses evaluated histologically and by determination of alkaline phosphatase activity are in very good agreement. The DBM/PC putty has good handling properties, can be molded into different shapes, and does not wash away from the application site. An advantage of adding PC is that it not only enhances the handling properties, but also boosts the osteoinductivity of the preparation.

A sensitive, rapid, reliable and quantitative method to check the bone forming potential of demineralized bone matrix (DBM) has been developed. The osteoinductivity of the bone morphogenetic proteins (BMPs), present in DBM, can be measured in vitro using a pluripotent myoblast C2C12 cell line. Alkaline phosphatase activity induced by co-incubation of DBM with C2C12 cells was dose-responsive and corresponds to the amount of active BMPs in DBM. Bone forming potential was simultaneously tested in vivo by implanting DBM intra-muscularly in nude rats. ALP activity induced in C2C12 cells, correlated with bone formation in vivo (r=0.88), determined by alkaline phosphatase activity, mineralization density and histomorphology of the DBM explants. Results from DBM batches, originating from five established Bone Banks, showed good consistency between in vitro and in vivo assays. However, DBM activity varied widely from bank to bank as well as from batch to batch within the same bank.