Novel cyclic olefin copolymer (COC) with high glass transition temperature, good mechanical performance, high transparency, and excellent film forming ability has been achieved in this work by effective copolymerization of ethylene and exo-1,4,4a,9,9a,10-hexahydro-9,10(1′,2′)-benzeno-l,4-methanoanthracene (HBMN). This bulky cyclic olefin comonomer can be simply prepared in good yield via Diels−Alder reaction. By utilizing constrained geometry catalyst (CGC) activated with Al( i Bu) 3 /[Ph 3 C][B(C 6 F 5 ) 4 ], ethylene/HBMN copolymer can be obtained with excellent production, high molecular weight, and a wide range of HBMN incorporation. 13 C NMR (DEPT) spectra reveal alternating ethylene−HBMN sequence can be detected at high HBMN incorporation. The glass transition temperature (T g ) of resulted copolymer enhances with increasing HBMN incorporation. A high T g up to 207.0°C is attainable at low comonomer incorporation of 30.4 mol %, which is 61°C higher than that of commercial norbornene (NB)-derived COC (54 mol %). The tensile test indicates that the ethylene/HBMN copolymer has good mechanical performance which is more flexible than ethylene/NB copolymer and the previously reported COC even at a higher T g level.

Vanadium(III) complexes bearing tridentate salicylaldiminato ligands (2a-f) [OC 6 H 4 CHdNL]-VCl 2 (THF) (L ) CH 2 CH 2 OMe, 2a; CH 2 CH 2 NMe 2 , 2b; CH 2 C 5 H 4 N, 2c; 8-C 9 H 6 N (quinoline), 2d; 2-MeSC 6 H 4 , 2e; 2-Ph 2 PC 6 H 4 , 2f) and tridentate β-enaminoketonato ligands [OC 6 H 8 CHdN-2-Ph 2 PC 6 H 4 ]VCl 2 (THF) (2g) and [O(Ph)CdCHCHdN-2-Ph 2 PC 6 H 4 ]VCl 2 (THF) (2h) were prepared from VCl 3 (THF) 3 by treating with 1.0 equiv of the deprotonated ligands in tetrahydrofuran (THF). These complexes were characterized by FTIR and mass spectrometry as well as elemental analysis. Structures of complexes 2e, 2f, and 2h were further confirmed by X-ray crystallographic analysis. These complexes were investigated as catalysts for olefin polymerization in the presence of organoaluminum compounds. On activation with Et 2 AlCl, complexes 2a-h exhibited high catalytic activities toward ethylene polymerization (up to 20.64 kg PE/mmol V • h • bar) even at high temperature, suggesting these catalysts possess high thermal stability. Moreover, high molecular weight polymers with unimodal molecular weight distribution can be obtained, indicating the single site behavior of these catalysts. The copolymerizations of ethylene and norbornene or 1-hexene with catalysts 2a-h were also explored in the presence of Et 2 AlCl, which led to high molecular weight poly(ethylene-co-1-hexene)s (M w up to 138 000) and poly(ethyleneco-norbornene)s (M w up to 164 000). Catalytic activity, comonomer incorporation, and polymer molecular weight can be controlled in a wide range by the variation of catalyst structure and the reaction parameters such as Al/V molar ratio, comonomer feed concentration, and polymerization reaction temperature.

Rapid cellular uptake and efficient drug release in tumor cells are two of the major challenges for cancer therapy. Herein, we designed and synthesized a novel pH-responsive polymer-drug conjugate system poly(2-(methacryloyloxy)ethyl choline phosphate)-b-poly(2-methoxy-2-oxoethyl methacrylate-hydrazide-doxorubicin) (PCP-Dox) to overcome these two challenges simultaneously. It has been proved that PCP-Dox can be easily and rapidly internalized by various cancer cells due to the strong interaction between multivalent choline phosphate (CP) groups and cell membranes. Furthermore, Dox, linked to the polymer carrier via acid-labile hydrazone bond, can be released from carriers due to the increased acidity in lysosome/endosome (pH 5.0-5.5) after the polymer prodrug was internalized into the cancer cells. The cell viability assay demonstrated that this novel polymer prodrug has shown enhanced cytotoxicity in various cancer cells, indicating its great potential as a new drug delivery system for cancer therapy.

Limited cellular uptake and inefficient intracellular drug release severely hamper the landscape of polymer drug nanocarriers in cancer chemotherapy. Herein, to address these urgent challenges in tumor treatment simultaneously, we integrated the multivalent choline phosphate (CP) and bioreducible linker into a single polymer chain, designed and synthesized a neoteric bioreducible polymer nanocarrier. The excellent hydrophility of these zwitterionic CP groups endowed high drug loading content and drug loading efficiency of doxorubicin to this drug delivery system (∼22.1 wt %, ∼95.9%). Meanwhile, we found that the multivalent choline phosphate can effectively enhance the internalization efficiency of this drug-loaded nanocarrier over few seconds, and the degree of improvement depended on the CP density in a single polymer chain. In addition, after these nanocarriers entered into the tumor cells, the accelerated cleavage of bioreducible linker made it possible for more cargo escape from the delivery system to cytoplasm to exert their cytostatic effects more efficiently. The enhanced therapeutic efficacy in various cell lines indicated the great potential of this system in anticancer drug delivery applications.

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Living drug delivery system has been proposed as new concept materials because it is able to communicate with biological system, sense subtle changes in body microenvironment caused by disease, and then make rapid response to cure in the early stage of disease. Herein, taking full advantage of the tumor hypoxia physiology and successive effects of photodynamic therapy (PDT), we designed a new living delivery system via combining the PDT and hypoxia-responsive chemotherapy, abbreviated as Ce6-PEG-Azo-PCL. Then, according to the fact that oxygen can be converted into reactive oxygen species during irradiation of the photosensitizer, tumor cells could be killed after the poly(ethylene glycol) (PEG) conjugated photosensitizer chlorine e6 was irradiated at the tumor site. What is more, the continuous consumption of oxygen could further amplify the hypoxia condition of tumor and trigger the disassembly of hypoxia-responsive azobenzene bridges at the tumor site to release loaded chemotherapeutics drugs doxorubicin. The ongoing collaboration with PDT and hypoxia-responsive chemotherapy provided an integrated therapeutic effect in vitro and in vivo to suppress tumor growth.

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Protein is an essential component of the living organism. The prediction of protein-protein interactions (PPIs) has important implications for understanding the behavioral processes of life, preventing diseases, and developing new drugs. Although the development of high-throughput technology makes it possible to identify PPIs in large-scale biological experiments, it restricts the extensive use of experimental methods due to the constraints of time, cost, false positive rate and other conditions. Therefore, there is an urgent need for computational methods as a supplement to experimental methods to predict PPIs rapidly and accurately. In this paper, we propose a novel approach, namely CNN-FSRF, for predicting PPIs based on protein sequence by combining deep learning Convolution Neural Network (CNN) with Feature-Selective Rotation Forest (FSRF). The proposed method firstly converts the protein sequence into the Position-Specific Scoring Matrix (PSSM) containing biological evolution information, then uses CNN to objectively and efficiently extracts the deeply hidden features of the protein, and finally removes the redundant noise information by FSRF and gives the accurate prediction results. When performed on the PPIs datasets Yeast and Helicobacter pylori , CNN-FSRF achieved a prediction accuracy of 97.75% and 88.96%. To further evaluate the prediction performance, we compared CNN-FSRF with SVM and other existing methods. In addition, we also verified the performance of CNN-FSRF on independent datasets. Excellent experimental results indicate that CNN-FSRF can be used as a useful complement to biological experiments to identify protein interactions.