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Cascade energy capturers based on supramolecular assembly have recently generated great research interest in the field of luminescent materials. Herein is reported a cucurbit[8]uril (CB[8])‐encapsulated coumarin‐bridged phenylpyridinium salt (G) to form biaxial polypseudorotaxane (G⊂CB[8]), which not only induces the phosphorescence of the guest G, but also activates the photodimerization of coumarin functional group in the CB[8] cavity (G‐dimer⊂CB[8]) to further boost its phosphorescence emission, extending the phosphorescence lifetime from 271.3 to 430.3 µs and the quantum yield from 5.1% to 25.7% in aqueous solution. After co‐assembly with amphiphilic calixarene (SC4AD), the supramolecular biaxial polypseudorotaxane G‐dimer⊂CB[8] is changed to the nanoparticle. Compared with the alone G‐dimer⊂CB[8], the phosphorescence intensity of G‐dimer⊂CB[8]@SC4AD is significantly enhanced with the phosphorescence lifetime extending to 2.11 ms. Subsequently, by doping commercial dye rhodamine B (RhB) in the G‐dimer⊂CB[8]@SC4AD assembly, an ultrahighly efficient phosphorescence‐harvesting energy transfer process occurs with an energy transfer efficiency (ΦET) of 72.3% and an antenna effect of 396.8. Furthermore, the cascaded room temperature phosphorescence harvesting system is constructed via introducing the secondary near‐infrared (NIR) acceptors Nile blue or Cy5 in the G‐dimer⊂CB[8]@SC4AD:RhB system, which possesses a good biocompatibility and is successfully applied to NIR delayed fluorescence targeted imaging in HeLa cell. [ABSTRACT FROM AUTHOR]

A multicolor room temperature phosphorescence (RTP) supramolecular photo‐switch encryption film is constructed by the coassembly of coumarin‐24‐crown‐8 (C24C8), diarylethene dicationic alkylammonium derivative (1), rhodamine B (RhB) and poly(vinyl alcohol) (PVA). Benefiting from the tightly binding of C24C8 and secondary alkylammonium ion, 1 formed noncovalent bridged bis(coumarin‐24‐crown‐8), which displayed photo‐switchable RTP with green afterglow (more than 5 s) after coassembly with PVA. Especially doping with RhB gave a photo‐switchable highly efficient phosphorescence‐harvesting system with multicolor through triplet‐to‐singlet Förster‐resonance energy transfer (TS‐FRET). The energy transfer efficiency and antenna effect of C24C8+RhB@PVA film reached 88.3% and 62.6 when the donor/acceptor ratio is 50:1, respectively. Therefore, diarylethene noncovalent bridged bis(coumarin‐24‐crown‐8) supramolecular assembly not only displays a multicolor photoluminescence‐switch, but also presents a phosphorescent photo‐switch with afterglow, which provides a simple and feasible way to construct smart RTP materials through host‐guest strategy. [ABSTRACT FROM AUTHOR]

Phosphorescent materials constructed by macrocyclic host confined guest has become a research hotspot in bioimaging. Herein, a highly efficient phosphorescent light‐harvesting supramolecular switch constructed by cucurbit[8]uril (CB[8]) encapsulated dicationic 6‐bromoisoquinoline derivative (G), sulfonatocalix[4]arene (SC4AD), near‐infrared (NIR) fluorescence dyes, and diarylethene molecular switch (1) is reported. First, the resulting supramolecular foldamer formed by G and CB[8] works as a phosphorescent donor with phosphorescence at 605 nm. When secondary assembling with SC4AD, the phosphorescent emission peak of G⊂CB[8] generates a hypsochromic shift to 583 nm with a 6.4‐fold enhancement of intensity. Further, NIR fluorescence dyes Nile Blue (NiB) and Sulfo‐Cyanine 5 (cy5) are introduced to the assembly as acceptors to construct phosphorescent light‐harvesting systems. As expected, light‐harvesting systems with energy transfer efficiency of 57.5%/75.7% and a high antenna effect of 359.7/247.7 are constructed at an efficient donor/acceptor ratio of 100:1/15:2 for NiB and cy5, respectively. After co‐assembly with diarylethene derivative (1), the phosphorescence transferred from G⊂CB[8]@SC4AD/NiB (or cy5) to 1 and caused the photoluminescence quenching after irradiation by 365 nm light. And the photoluminescence of the light‐harvesting system was restored with the irradiation by >450 nm light. The highly efficient phosphorescent light‐harvesting system is applied to lysosome targeted imaging in HeLa cells and information encryption. [ABSTRACT FROM AUTHOR]

A triazine pyridinium derivative (TAZpy) was encapsulated into the cavity of a cucurbit[7]uril and further assembled with sulfonatocalix[4]-arene, hyaluronic acid and commercial dyes, which not only achieved fluorescence cascade enhancement and an effective FRET process based on macrocyclic confinement, but was also applied in two-photon NIR targeted cell imaging. [ABSTRACT FROM AUTHOR]

This study investigated the effects of grafting on the carbohydrate status and the enzymes of carbohydrate metabolism in self-grafted and grafted cucumber seedlings using the salt-tolerant pumpkin rootstock ‘Qingzhen 1’ ( Cucurbita maxima × Cucurbita moschata ) under 80 mM Ca(NO 3 ) 2 stress for 6 d. The growth of self-grafted seedlings was significantly inhibited after the treatment of Ca(NO 3 ) 2 stress, whereas the inhibition of growth was alleviated in pumpkin rootstock-grafted seedlings. Ca(NO 3 ) 2 stress increased the contents of the total soluble sugar, sucrose and fructose, but decreased the starch content in rootstock-grafted leaves. However, compared with self-grafted plants, rootstock-grafted seedlings were observed with a higher content of sucrose and total soluble sugar (TSS) under salt stress. Rootstock-grafted seedlings exhibited higher activities of acid invertase (AI), neutral invertase (NI) and phosphate sucrose synthase (SPS) of sucrose metabolism in leaves than that of self-grafted seedlings under salinity. Moreover, the activities of fructokinase (FK), hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) of glycolysis were maintained at a higher level in leaves of rootstock-grafted seedlings after Ca(NO 3 ) 2 stress. Additionally, rootstock-grafting decrease the high percentage enhancement of key enzymes gene expression in glycolysis in the scion leaves of cucumber seedlings induced by salt stress. These results suggest that the rootstock-grafting improved salt tolerance, which might play a role in elevated sucrose metabolism and a glycolytic pathway regulated by the pumpkin rootstock. [ABSTRACT FROM AUTHOR]

• Significant upregulation of ANXA2 expression is evidenced in thyroid carcinoma by multiple detecting approaches. • Upregulated ANXA2 is strongly related to the development of thyroid carcinoma. • ANXA2 coexpressed genes are mostly enriched in the pathway of extracellular matrix-receptor interaction. • ANXA2 is a target of miR-23b-3p in thyroid carcinoma. Thyroid carcinoma (THCA) is one of the most frequent endocrine cancers and has increasing morbidity. Annexin A2 (ANXA2) has been found to be highly expressed in various cancers; however, its expression level and potential mechanism in THCA remain unknown. This study investigated the clinicopathological value and primary molecular machinery of ANXA2 in THCA. Public RNA-sequencing and microarray data were obtained and analyzed with ANXA2 expression in THCA and corresponding non-cancerous thyroid tissue. A Pearson correlation coefficient calculation was used for the acquisition of ANXA2 coexpressed genes, while edgR, limma, and Robust Rank Aggregation were employed for differentially expressed gene (DEG) in THCA. The probable mechanism of ANXA2 in THCA was predicted by gene ontology and pathway enrichment. A dual-luciferase reporter assay was employed to confirm the targeting relationships between ANXA2 and its predicted microRNA (miRNA). Expression of ANXA2 was significantly upregulated in THCA tissues with a summarized standardized mean difference of 1.09 (P < 0.0001) based on 992 THCA cases and 589 cases of normal thyroid tissue. Expression of ANXA2 was related to pathologic stage. Subsequently, 1442 genes were obtained when overlapping 4542 ANXA2 coexpressed genes with 2248 DEGs in THCA; these genes were mostly enriched in pathways of extracellular matrix-receptor interaction, cell adhesion molecules, and complement and coagulation cascades. MiR-23b-3p was confirmed to target ANXA2 by dual-luciferase reporter assay. Upregulated expression of ANXA2 may promote the malignant biological behavior of THCA by affecting the involving pathways or being targeted by miR-23b-3p. [ABSTRACT FROM AUTHOR]