Controlled Hierarchical Self-Assembly of Nanoparticles and Chiral Molecules into Tubular Nanocomposites.

In this work, we show how the kinetics of molecular self-assembly can be coupled with the kinetics of the colloidal self-assembly of inorganic nanoparticles, which in turn drives the formation of several distinct hierarchically assembled tubular nanocomposites with lengths over tens of micrometers. These colloidal nanoparticles primarily serve as "artificial histones," around which the as-assembled supramolecular fibrils are wound into deeply kinetically trapped single-layered nanotubes, which leads to the formation of tubular nanocomposites that are resistant to supramolecular transformation thermally. Alternatively, when these nanoparticles are aggregated prior to the event of molecular self-assembly, these as-formed nanoparticle "oligomers" would be encapsulated into the thermodynamically favored double-layer supramolecular nanotubes, which enables the non-close-packing of nanoparticles inside the nanotubes and results in the nanoparticle superlattices with an open channel. Furthermore, increasing the amounts of nanoparticles enables the assembly of nanoparticles into pseudohexagonal superlattices at the external surface in a sequential fashion, which ultimately drives the formation of triple-layered hierarchically assembled tubular nanocomposites. Importantly, the sense of helicity transfers from the supramolecular nanotubes to the pseudo nanoparticle superlattices with a chiral vector of (2, 9). Our findings represent a strategy for controlling the hierarchical assembly bridging supramolecular chemistry to the inorganic solids to realize the complexity by design.

Metal-Organic Gels from Silver Nanoclusters with Aggregation-Induced Emission and Fluorescence-to-Phosphorescence Switching.

Luminescent metal nanoclusters (NCs) are emerging as a new class of functional materials that have rich physicochemical properties and wide potential applications. In recent years, it has been found that some metal NCs undergo aggregation-induced emission (AIE) and an interesting fluorescence-to-phosphorescence (F-P) switching in solutions. However, insights of both the AIE and the F-P switching remain largely unknown. Now, gelation of water soluble, atomically precise Ag9 NCs is achieved by the addition of antisolvent. Self-assembly of Ag9 NCs into entangled fibers was confirmed, during which AIE was observed together with an F-P switching occurring within a narrow time scale. Structural evaluation indicates the fibers are highly ordered. The self-assembly of Ag9 NCs and their photoluminescent property are thermally reversible, making the metal-organic gels good candidates for luminescent ratiometric thermometers.

An Immunity-Related Gene Model Predicts Prognosis in Cholangiocarcinoma.

The prognosis of patients with cholangiocarcinoma (CCA) is closely related to both immune cell infiltration and mRNA expression. Therefore, we aimed at conducting multi-immune-related gene analyses to improve the prediction of CCA recurrence. Immune-related genes were selected from the Gene Expression Omnibus (GEO), The Cancer Genome Atlas (TCGA), and the Immunology Database and Analysis Portal (ImmPort). The least absolute shrinkage and selection operator (LASSO) regression model was used to establish the multi-gene model that was significantly correlated with the recurrence-free survival (RFS) in two test series. Furthermore, compared with single genes, clinical characteristics, tumor immune dysfunction and exclusion (TIDE), and tumor inflammation signature (TIS), the 8-immune-related differentially expressed genes (8-IRDEGs) signature had a better prediction value. Moreover, the high-risk subgroup had a lower density of B-cell, plasma, B-cell naïve, CD8+ T-cell, CD8+ T-cell naïve, and CD8+ T-cell memory infiltration, as well as more severe immunosuppression and higher mutation counts. In conclusion, the 8-IRDEGs signature was a promising biomarker for distinguishing the prognosis and the molecular and immune features of CCA, and could be beneficial to the individualized immunotherapy for CCA patients.

Nobiletin suppresses cholangiocarcinoma proliferation via inhibiting GSK3ß.

Background: Cholangiocarcinoma (CCA) is a type of hepatobiliary cancer characterized by uncontrolled cell proliferation, with a poor prognosis and high mortality. Nobiletin (NBT) is a promising anti-tumor compound derived from the peels of oranges and other citrus plants, citrus plant. But the effect of NBT on CCA remains unknown. Results: Our data showed that NBT suppressed CCA cell proliferation in vitro and in vivo. Colony formation and Edu assay indicated that NBT inhibited cell proliferation. Cell cycle analysis showed that NBT arrested the cell cycle in G0/G1 phase. Target prediction showed that GSK3ß was a direct target. Western blot and immunofluorescence confirmed that NBT reduced the phosphorylation of GSK3ß. The antiproliferative effect of NBT was intercepted in GSK3ß knockdown CCA cells. The cellular thermal shift assay (CETSA) showed NBT directly bound to GSK3ß. Finally, NBT showed an anti-proliferative effect in tumor-bearing mice with no hepatotoxicity. Conclusion: NBT could inhibit CCA proliferation, and the pharmacological activity of NBT in CCA was attributed to its direct binding to GSK3ß. We suggested that NBT might be a potential natural medicine in CCA treatment.

Supramolecular Chirality from Hierarchical Self-Assembly of Atomically Precise Silver Nanoclusters Induced by Secondary Metal Coordination.

Chiral assembly of metal nanoparticles (NPs) into complex superstructures has been widely studied, but their formation mechanisms still remain mysterious due to the lack of precise structural information from the metal-organic interface to metallic kernel. As "molecular models" of metal NPs, atomically precise metal nanoclusters (NCs) used in the assembly of a macroscale superstructure will provide details of microscopic structure for deep understanding of such highly sophisticated assemblies; however, chiral superstructures have not been realized starting from achiral metal NCs with atomic precision. Herein, we report the supramolecular assembly of a water-soluble silver NC ((NH4)9[Ag9(mba)9], H2mba = 2-mercaptobenzoic acid, abbreviated as Ag9-NCs hereafter) into chiral hydrogels induced by the coordination of secondary metal ions. Single crystal X-ray diffraction reveals the triskelion-like structure of Ag9-NCs with a pseudochiral conformation caused by special arrangement of the peripheral mba2- ligands. The enantioselective orientation of the peripheral carboxyl group facilitates the assembly of Ag9-NCs into nanotubes with a chiral cubic (I*) lattice when coordinating to Ba2+. The nanotubes can further intertwine into one-dimensional chiral nanobraids with a preferred left-handed arrangement. These multiple levels of chirality can be tuned by drying, during which the I* phase is missing but the chiral entanglement of the nanotubes is enhanced. Through the gelation of atomically precise, achiral NCs coordination of secondary metal ions, chiral amplification of superstructures was realized. The origination of the chirality at different length scales was also discussed.

pH-guided self-assembly of silver nanoclusters with aggregation-induced emission for rewritable fluorescent platform and white light emitting diode application.

Metal nanoclusters (NCs) as a new type of fluorescent material have attracted great interest due to their unique electronic structure and outstanding optical properties. However, limited success has been achieved in the preparation of water-soluble NCs with high luminous intensity. In this article, the significant luminescence properties of 4-mercaptobenzoic acid (H2mba)-capped Ag NCs induced by hydrochloric acid (HCl) through self-assembly strategies were reported and the water-soluble protonated silver nanoclusters (Ag-H-NCs) can be obtained. The original non-luminescent Ag NCs exhibit stable and bright luminescence resulting from aggregation-induced emission (AIE) by forming an ordered nanorod structure after assembly. Optical analysis allows for the establishment of relationships between ordered alignment and emission of Ag NCs components and it can be concluded that the ordered nanostructures are constructed by non-covalent interaction (hydrogen bond, π-π stacking, etc.) which effectively inhibits the intramolecular vibration and rotation of the ligand, thereby increasing the emission intensity of Ag NCs. Due to the outstanding optical behavior of the aqueous solution of Ag-H-NCs, it can be used as a rewritable fluorescent platform and a white light emitting diode (LED). The pH-guided strategy enriches the supramolecular self-assembly of novel noble metal NCs, which makes them a good candidate for optical materials.