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1.
J Colloid Interface Sci ; 658: 836-845, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38154246

RESUMO

Composite solid electrolytes (CSEs) have emerged as promising contenders for tackling the safety concerns associated with lithium metal batteries and attaining elevated energy densities. Nonetheless, augmenting ion conductivity and curtailing the growth of lithium dendrites within the electrolyte remain pressing challenges. We have developed CSEs featuring a unique structure, in which Li6.4La3Zr1.4Ta0.6O12 (LLZTO) is distributed in a gradient decline from the center to both sides (GCSE). This distinctive arrangement encompasses heightened polymer content at the edges, thereby enhancing the compatibility between CSEs and electrode materials. Concurrently, the escalated LLZTO content at the center functions to impede the proliferation of lithium dendrites. The uniform gradient distribution state facilitates the consistent and rapid transport of lithium ions. At room temperature, GCSE exhibits an ionic conductivity of 1.5 × 10-4 S cm-1, with stable constant current cycling of lithium for over 1200 h. Furthermore, CR2032 coin batteries with a LiFePO4 (LFP)|GCSE|Li configuration demonstrate excellent rate performance and cycling stability, yielding a discharge capacity of 120 mA h g-1 at 0.5C and retaining 90 % capacity after 200 cycles at 60 °C. Flexible solid electrolytes with gradient structures offer substantial advantages in dealing with ion conductivity and inhibition of lithium dendrites, thereby expected to propel the practical application of lithium metal batteries.

2.
Angew Chem Int Ed Engl ; 62(48): e202313265, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37819780

RESUMO

We herein report a synthetic strategy for alternating copolymers of styrene and substituted styrenes by utilizing α-styryl boronate pinacol ester (StBpin) as the co-monomer through radical alternating copolymerization followed by protodeboronation. The excellent alternating polymerization behavior of the StBpin co-monomer in such a radical polymerization system is considered to be attributed to the steric hindrance and radical stabilization exerted by the Bpin group. This strategy is effective with a wide range of substituted styrene co-monomers regardless of the electronic nature of the substituents, and the protodeboronation of the alternating Bpin-containing polymers is highly efficient without polymer backbone alternation. RAFT living polymerization was also compatible with this approach. Thus, this strategy provides a way to build-up alternating copolymers consisting of similar styrene-type co-monomers, which has been inaccessible by conventional synthetic methods.

3.
Chem Commun (Camb) ; 58(24): 3909-3912, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35237776

RESUMO

The copper-catalyzed cross-coupling of alkynes and α-diazoesters has been applied in the synthesis of polyallenoates for the first time. The polymerization tolerated various functional groups and afforded the polyallenoates with high molecular weight. With chiral guanidinium bromide as a ligand, the axial chirality of the allene moiety could be generated with high enantioselectivity during the polymerization process.


Assuntos
Alcinos , Cobre , Catálise , Ligantes
4.
J Cancer ; 11(5): 1257-1269, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31956372

RESUMO

Background: Latent membrane protein 1 (LMP1) is known as an oncogenic protein encoded by the EBV genome. The purpose of this study was to investigate the mechanism of LMP1-induced cell epithelial-mesenchymal transition (EMT). Methods: The NP69 cell line of nasopharyngeal epithelial cells with high expression of LMP1 was established to observe the effect of high expression of LMP1 on cell growth, proliferation, cycle, apoptosis, migration and invasion. We used proteomics to screen and identify differentially expressed proteins related to LMP1-mediated epithelial cell transformation. Then, we analyzed the expression and significance of differentially expressed calreticulin (CRT) in nasopharyngeal carcinoma (NPC), and observed the effect of CRT expression on EMT in CNE2 cells of NPC. Finally, the expression of neuropilin-1 (NRP1), which is a protein downstream of the EMT-related signaling pathway TGF-ß (transforming growth factor ß), was detected. Results: LMP1 promoted NP69 cells proliferation, inhibited apoptosis and induced EMT. We identified 22 differentially expressed proteins associated with LMP1-induced EMT. Among them, CRT expression level was significantly increased in NPC compared with adjacent tissues, and was interrelated with TNM staging and lymph node metastasis of NPC. After knockdown of CRT expression, the phenomenon of cell EMT was reduced and the ability of cell migration and invasion was weakened. CRT regulated NRP1 expression by affecting SMAD3 phosphorylation. Conclusion: LMP1 induced cell EMT via TGF-ß/Smad3/NRP1 pathway, which promoted migration and invasion of NPC cells.

5.
Oncol Lett ; 19(1): 17-29, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31897111

RESUMO

Gastric cancer is one of the most common gastrointestinal tumor types, and the incidence and mortality rates are higher in men compared with women. Various studies have revealed that gastric cancer is a spectrum of tumor types, which have biological and genetic diversity. It has proven to be difficult to improve the overall survival and disease-free survival of patients with gastric cancer through the use of traditional surgery and chemoradiation, as gastric cancer is usually identified at an advanced stage. In consequence, the outcome is frequently poor. Thus, novel biomarkers and anticancer targets are required to improve the outcome. As the identification of biomarkers has increased due to advances in research and the greater availability of bioinformatics and functional genomics, the potential therapeutic regimens available have also increased concurrently. These advances have also improved the ability to predict responses to chemotherapy, targeted therapy and immunotherapy, whilst other biomarkers predict post-treatment survival and recurrence based on their expression. This review focuses closely on the important functions of biomarkers in the timely diagnosis and treatment of gastric cancer, in addition to the advances in the study of certain novel markers in gastric cancer.

6.
J Am Chem Soc ; 140(26): 8069-8073, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29894184

RESUMO

Nucleophilic attack on carbon-based electrophiles is a central reactivity paradigm in chemistry and biology. The steric and electronic properties of the electrophile dictate its reactivity with different nucleophiles of interest, allowing the opportunity to fine-tune electrophiles for use as coupling partners in multistep organic synthesis or for covalent modification of proteins in drug discovery. Reactions that directly transform inexpensive chemical feedstocks into versatile carbon electrophiles would therefore be highly enabling. Herein, we report the catalytic, regioselective oxidative cyanation of conjugated and nonconjugated alkenes using a homogeneous copper catalyst and a bystanding N-F oxidant to furnish branched alkenyl nitriles that are difficult to prepare using existing methods. We show that the alkenyl nitrile products serve as electrophilic reaction partners for both organic synthesis and the chemical proteomic discovery of covalent protein ligands.


Assuntos
Alcenos/química , Nitrilas/síntese química , Catálise , Estrutura Molecular , Nitrilas/química , Oxirredução
7.
ACS Catal ; 8(4): 3650-3654, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-30740261

RESUMO

A method to achieve enantioselective 1,4-hydroboration of terminal enynes to access allenyl boronates under CuH catalysis is described. The reaction typically proceeds in a highly stereoselective manner and tolerates an array of synthetically useful functional groups. The utility of the enantioenriched allenyl boronate products is demonstrated through several representative downstream derivatizations.

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