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901.
Molecular recognition in water is an important challenge in supramolecular chemistry. Surface‐core double cross‐linking of template‐containing surfactant micelles by the click reaction and free radical polymerization yields molecularly imprinted nanoparticles (MINPs) with guest‐complementary binding sites. An important property of MINP‐based receptors is the surface‐cross‐linking between the propargyl groups of the surfactants and a diazide cross‐linker. Decreasing the number of carbons in between the two azides enhanced the binding affinity of the MINPs, possibly by keeping the imprinted binding site more open prior to the guest binding. The depth of the binding pocket can be controlled by the distribution of the hydrophilic/hydrophobic groups of the template and was found to influence the binding in addition to electrostatic interactions between oppositely charged MINPs and guests. Cross‐linkers with an alkoxyamine group enabled two‐stage double surface‐cross‐linking that strengthened the binding constants by an order of magnitude, possibly by expanding the binding pocket of the MINP into the polar region. The binding selectivity among very similar isomeric structures also improved. 相似文献
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Shengping Yu Yang Liu Zhen Zhang Jingya Zhang Guisen Zhao 《Bioorganic & medicinal chemistry》2019,27(15):3319-3327
2,3-Indolinedione derivatives have been identified as a novel class of promising agents for cancer treatment. In this study, eighteen 2,3-indolinedione derivatives were designed and synthesized, and their anticancer activities against mantle cell lymphoma (MCL) cells were evaluated. Most of them exhibited significant antiproliferative activity against the tested cell lines, and compound K5 was the most potent (MCL cellular IC50 = 0.4–0.7 μM). Further, compound K5 could induce cell apoptosis and cell cycle arrest in G2/M phase. Additionally, the results of drug-likeness analysis demonstrated that these novel 2,3-indolinedione derivatives could have potential as novel treatment strategies for MCL. 相似文献
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Guofeng Yang Yanqin Ju Shangfeng Liu Shouliang Zhao 《Cell biology international》2019,43(11):1276-1285
NG2+ cells have been proven to differentiate into odontoblasts in vivo, and their contribution to odontoblasts is significantly increased, especially after tooth injury. However, their characteristics in vitro, especially under an inflammatory environment, are still not fully understood. Therefore, this study aimed to explore their proliferation, migration, and odontoblastic differentiation ability after treatment with lipopolysaccharide (LPS) in vitro. In our study, NG2 + cells were isolated from the human dental pulp by magnetic‐activated cell sorting, and these isolated cells were proven to be NG2 + by immunostaining. When compared with human dental pulp cells (hDPCs), the NG2 + cells showed no significant differences in cell migration with or without LPS incubation, but their proliferative ability was weaker. When treated with LPS, NG2 + cells expressed elevated levels of pro‐inflammatory cytokines including interleukin‐1β (IL‐1β), IL‐6, IL‐8, and tumor necrosis factor‐α, and among these, the expression of IL‐1β and IL‐6 were higher than that of hDPCs. Their multipotent differentiation potential was confirmed by the induction of odontoblastic and adipogenic differentiation, and LPS increased their odontoblastic differentiation capacity. In the odontoblastic differentiation process, Wnt5a, BMP2, and BMP7 mRNA were increased, while the canonical Wnt‐related genes were decreased. In conclusion, the LPS stimulation promotes the migration, proliferative, and odontoblastic differentiation ability of NG2 + cells from the human dental pulp in vitro, and bone morphogenetic protein and the noncanonical Wnt pathway may be involved in their odontoblastic differentiation. These results indicated their special roles in tooth injury repair and potential application in pulp regeneration. 相似文献
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