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Angelica sinensis, commonly known as Dong Quai in Europe and America and as Dang-gui in China, is a medicinal plant widely utilized for the prevention and treatment of osteoporosis. In this study, we report the discovery of a new category of phthalide from Angelica sinensis, namely falcarinphthalides A and B (1and 2), which contains two fragments, (3R,8S)-falcarindiol (3) and (Z)-ligustilide (4). Falcarinphthalides A and B (1and 2) represent two unprecedented carbon skeletons of phthalide in natural products, and their antiosteoporotic activities were evaluated. The structures of 1and 2, including their absolute configurations, were established using extensive analysis of NMR spectra, chemical derivatization, and ECD/VCD calculations. Based on LC-HR-ESI-MS analysis and DFT calculations, a production mechanism for 1and 2involving enzyme-catalyzed Diels−Alder/retro-Diels−Alder reactions was proposed. Falcarinphthalide A (1), the most promising lead compound, exhibits potent in vitro antiosteoporotic activity by inhibiting NF-κB and c-Fos signaling-mediated osteoclastogenesis. Moreover, the bioinspired gram-scale total synthesis of 1, guided by intensive DFT study, has paved the way for further biological investigation. The discovery and gram-scale total synthesis of falcarinphthalide A (1) provide a compelling lead compound and a novel molecular scaffold for treating osteoporosis and other metabolic bone diseases.

4-Hydroxy pyridones are a class of fungi-derived polyketide–nonribosomal peptide products featuring a core of 4-hydroxy-2-pyridone which have a wide range of biological activities. Genome mining of in-house strains using polyketide synthase–nonribosomal peptide synthase as a query identified an endophyte Tolypocladiumsp. 49Y, which possesses a potential 4-hydroxy pyridone biosynthetic gene cluster. Heterologous expression in Aspergillus oryzaeNSAR1 revealed that this gene cluster is functional and able to produce a rare type of 4-hydroxy pyridones called tolypyridones (compounds 3and 4). Tolypocladiumsp. 49Y was grown in a variety of media which led to the isolation of six 4-hydroxy pyridones (5–10) and one pyrrolidone (11) from a rice culture, and compounds 3and 9showed antifungal activity. These latter compounds are different from those obtained by heterologous expression. This study shows that both heterologous expression and cultivation of the native host are complementary approaches to discover new natural products.

A rapid freezing/lyophilizing/reinforcing process is suggested to fabricate reinforced keratin/hydroxyapatite (HA) scaffold with improved mechanical property and biocompatibility for tissue engineering. The keratin, extracted from human hair, and HA mixture were rapidly frozen with liquid nitrogen and then lyophilized to prepare keratin/HA laminar scaffold. The scaffold was then immersed in PBS for reinforcement treatment, and followed by a second lyophilization to prepare the reinforced keratin/HA scaffold. The morphology, mechanical, chemical, crystal and thermal property of the keratin/HA scaffold were investigated by SEM, FTIR, XRD, DSC, respectively. The results showed that the keratin/HA scaffold had a high porosity of 76.17 ± 3%. The maximum compressive strength and compressive modulus of the reinforced scaffold is 0.778 and 3.3 MPa respectively. Subcutaneous implantation studies in mice showed that in vivothe scaffold was biocompatible since the foreign body reaction seen around the implanted scaffold samples was moderate and became minimal upon increasing implantation time. These results demonstrate that the keratin/HA reinforced scaffold prepared here is promising for biomedical utilization.

The three-dimensional spatial target tracking based on wireless communication technology has attracted more and more attention due to its importance in the field of Internet of Things.However,there are still some problems including calculation overhead is too high and power consumption is too large.Thus,a distributed three-dimensional target tracking mechanism for the environment of the Internet of Things is proposed.The network structure in the algorithm uses spatial clustering structure, which includes two tier sleep scheduling mechanisms and unite cluster head mechanism. A spatial segmental linear fitting method is adopted to track the target,which have effectively reduced the network overhead and improved tracking efficiency. It also provides a scheduling strategy how to wake up the sensor node guarantee to continue tracking it,when the mobile target lost.Simulation results show that the algorithm is better than the existing target tracking algorithm in tracking efficiency and have a lower power consumption.

Energy saving becomes one of the most important design considerations in the WBAN applications, and the power consumption is required to be strictly controlled. However, traditional WSN route protocols can't solve this very well. In this paper, we propose the cross-layer route which integrates adaptive sleep technology and DSR protocol with dynamic physical level power control scheme to meet the harsh requirements by reducing the power consumption of each sensor node. We developed a mathematical model of the send power control and analyzed the total battery energy consumption to forward a symbol. The experimental results on NS-2 platform indicate that the network life span and data package re-send rate of the improved DSR is better than the traditional one, and better fits the energy requirements of WBAN scenario.

Diphyllin-7′-O-β-D-glucoside, a podophyllotoxin derivative, was isolated from the roots of Dysosma versipellis.The 1H and 13C NMR spectra acquired at 300 K exhibited doubling of signals, suggesting the existence of two rotamers in solution. Variable-temperature 1H NMR experiments indicated a dynamic exchange process between the two rotamers. DFT calculations verified nearly equal energies for the two rotamers about the single bond C7′-O7.