Skeleton Extraction for Articulated Objects with the Spherical Unwrapping Profiles.

Embedding unified skeletons into unregistered scans is fundamental to finding correspondences, depicting motions, and capturing underlying structures among the articulated objects in the same category. Some existing approaches rely on laborious registration to adapt a predefined LBS model to each input, while others require the input to be set to a canonical pose, e.g. T-pose or A-pose. However, their effectiveness is always influenced by the water-tightness, face topology, and vertex density of the input mesh. At the core of our approach lies a novel unwrapping method, named SUPPLE  (Spherical UnwraPping ProfiLEs), which maps a surface into image planes independent of mesh topologies. Based on this lower-dimensional representation, a learning-based framework is further designed to localize and connect skeletal joints with fully convolutional architectures. Experiments demonstrate that our framework yields reliable skeleton extractions across a broad range of articulated categories, from raw scans to online CADs.

Palbociclib and Michael-acceptor hybrid compounds as CDK4/6 covalent inhibitors: Improved potency, broad anticancer spectrum and overcoming drug resistance.

To search for potent CDK4/6 covalent inhibitors, total 14 compounds have been designed and synthesized by connecting different Michael-acceptor to the piperazine moiety of palbociclib. All the compounds displayed good antiproliferative activity against human hepatoma cell (HepG2), non-small cell lung cancer (A549), and breast cancer (MDA-MB-231 and MCF-7) cell lines. In particular, compound A4 showed the highest inhibitory activity to MDA-MB-231 and MCF-7 cells with IC50 values of 0.51 µM and 0.48 µM, respectively. More importantly, A4 also showed strong inhibition against MDA-MB-231/palbociclib cells, indicating that A4 could effectively avoid the resistance of palbociclib. In the enzyme test, A4 showed selective inhibitory activity against CDK4/6, with the IC50 value of 18 nM and 13 nM, respectively. It was also found that A4 could efficiently induce apoptosis and arrest the cell cycle at G0/G1 phase. Moreover, A4 could significantly decrease the phosphorylation level of CDK4 and CDK6. HPLC and molecular modeling studies suggested that A4 could form a covalent bond with the target protein.

Inhibition of oxygen dimerization by local symmetry tuning in Li-rich layered oxides for improved stability.

Li-rich layered oxide cathode materials show high capacities in lithium-ion batteries owing to the contribution of the oxygen redox reaction. However, structural accommodation of this reaction usually results in O-O dimerization, leading to oxygen release and poor electrochemical performance. In this study, we propose a new structural response mechanism inhibiting O-O dimerization for the oxygen redox reaction by tuning the local symmetry around the oxygen ions. Compared with regular Li2RuO3, the structural response of the as-prepared local-symmetry-tuned Li2RuO3 to the oxygen redox reaction involves the telescopic O-Ru-O configuration rather than O-O dimerization, which inhibits oxygen release, enabling significantly enhanced cycling stability and negligible voltage decay. This discovery of the new structural response mechanism for the oxygen redox reaction will provide a new scope for the strategy of enhancing the anionic redox stability, paving unexplored pathways toward further development of high capacity Li-rich layered oxides.

Anti-lung cancer activity and inhibitory mechanisms of a novel Calothrixin A derivative.

AIMS: CAA45 is a calothrixin A (CAA) analogue with anti-cancer activity at nanomolar concentration. This study aimed to investigate the anti-lung cancer activity of CAA45 and explore its mechanisms of actions. MAIN METHODS: CAA and CAA45 were synthesized and their inhibition on DNA topoisomerase I (Topo I) performed by evaluating the relaxation of supercoiled pBR322 plasmid DNA and their anti-lung cancer capacity determined by cytotoxic assays, cell migration, cell cycle, cell apoptosis, cell autophagy and related signaling proteins expression by western blot. KEY FINDINGS: CAA45 significantly inhibited human non-small cancer cell A549 and NCI-H1650 cells growth with IC50 values of 110 and 230 nM, respectively. In the A549 xenograft models, CAA45 displayed strong antitumor activities at a dose of 10 mg/kg. CAA45 inhibited Topo I activity and caused the cell cycle arrest at S phase, which also reduced A549 cell migration by inhibiting MMP-2 and MMP-9 expressions. Furthermore, CAA45 induced A549 cell apoptosis and autophagy. The apoptosis pathway was involved in the release of cytochrome c and caspase activation. CAA45 also inhibited Akt, activated JNK and up-regulated p53 signals in A549 cells, which may serve as a modulator to induce apoptosis and autophagy in cancer cells. SIGNIFICANCE: CAA45 exerted its anti-lung cancer effect via inhibition of Topo I, resulting in cell cycle arrest and cell migration, induction of mitochondria mediated cell apoptosis and autophagy via PI3K/Akt/JNK/p53 pathway. All these observations suggested that CAA45 could be a promising lead for anti-cancer drug discovery.

Chiral Amino Alcohol Accelerated and Stereocontrolled Allylboration of Iminoisatins: Highly Efficient Construction of Adjacent Quaternary Stereogenic Centers.

We have developed a highly efficient asymmetric allylboration of ketimines with nonchiral γ,γ-disubstituted allylboronic acids by using a chiral amino alcohol as the directing group, which is otherwise challenging. The amino alcohol not only serves as a cheap source of nitrogen and chirality, but also dramatically enhances the reactivity. The versatility of this method was demonstrated by its ability to access all four stereoisomers with adjacent quaternary carbon centers. A reaction model was proposed to explain the diastereoselectivity and the rate-accelerating effect.