Dual targeting total saponins of Pulsatilla of natural polymer crosslinked gel beads with multiple therapeutic effects for ulcerative colitis.

Oral colon targeted drug delivery system (OCTDDS) is desirable for the treatment of ulcerative colitis (UC). In this study, we designed a partially oxidized sodium alginate-chitosan crosslinked microsphere for UC treatment. Dissipative particle dynamics (DPD) was used to study the formation and enzyme response of gel beads from a molecular perspective. The formed gel beads have a narrow particle size distribution, a compact structure, low cytotoxicity and great colon targeting in vitro and in vivo. Animal experiments demonstrated that gel beads promoted colonic epithelial barrier integrity, decreased the level of pro-inflammatory factors, accelerated the recovery of intestinal microbial homeostasis in UC rats and restored the intestinal metabolic disorders. In conclusion, our gel bead is a promising approach for the treatment of UC and significant for the researches on the pathogenesis and treatment mechanism of UC.

Fluoxetine Ameliorates the Aggravation of UC Symptoms in C57BL/6 Mice Induced by CUMS.

OBJECTIVE: Patients with chronic ulcerative colitis (UC) often have mental symptoms such as depression and anxiety, and stress can lead to gastrointestinal diseases. However, the correlation between mental stress and UC is unclear. In this paper, chronic unpredictable mild stress (CUMS) was utilized to evaluate the involvement of mental factors in the pathogenesis of UC. METHODS: The CUMS model was used to evaluate the direct/indirect involvement of mental factors in the pathogenesis of UC. The behavior was evaluated by the open field, forced swimming, and tail suspension tests. Body weight, the disease activity index (DAI) score, colon length, and HE staining of colon tissue were used to evaluate the action of CUMS and fluoxetine. RESULTS: The results showed that weight loss and the DAI score increased in CUMS mice, but they had no meaningful effect on colon length and morphological structure of colon tissue. However, CUMS aggravated dextran sulfate sodium (DSS)-induced colon length shortening and colon morphological structure damage. Fluoxetine significantly improved the DAI score, shortened colon length, and damaged morphology and structure of the colons induced by CUMS combined with DSS in mice. Fluoxetine also decreased the level of IL-6 in the serum and the TNF-α and IFN-γ levels of colon tissue. Fluoxetine simultaneously improved behavioral abnormalities induced by CUMS combined with DSS in mice. CONCLUSION: CUMS aggravated the UC symptoms induced by DSS, and fluoxetine could improve the UC symptoms due to its improvement in the inflammatory level and behavioral abnormalities.

Free-standing Pt-Ni nanowires catalyst for H2 generation from hydrous hydrazine.

Free-standing Pt-Ni nanowires were fabricated by a one-pot solvothermal method. Nanowires with an optimal Pt/Ni ratio of 1.86 exhibited a high activity and a 100% H2 selectivity for hydrous hydrazine decomposition at mild temperatures, which are comparable to the levels of supported catalysts. Our study reveals for the first time that basic support is not a prerequisite for achieving favorable catalytic performance and provides a renewed perspective for the design of advanced catalysts for on-demand H2 generation from hydrous hydrazine.

Supramolecular Engineering Strategy to Construct BODIPY-Based White Light Emission Materials.

Two kinds of 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) dyads BDP-OH containing 4-hydroxystyrene groups and BDP-PY bearing pyridinyl units were prepared. In addition, a naphthalene derivative NAP-PY modified by pyridinyl moieties substituent was made. The above three dyads could be used to construct white-light emission (WLE) material by a supramolecular engineering strategy due to their three primary colors of blue, green and red. The supramolecular correlations between the hydroxyl group of BDP-OH and the pyridinyl groups of NAP-PY and BDP-PY were confirmed by 1 H NMR titration, 2D NOESY and FTIR. A fluorescence monitor application was carried out based on the realization of WLE. This work might be useful for designing other WLE supramolecular systems and image display.

NiPt Nanoparticles Anchored onto Hierarchical Nanoporous N-Doped Carbon as an Efficient Catalyst for Hydrogen Generation from Hydrazine Monohydrate.

Catalytic decomposition of the hydrogen-rich hydrazine monohydrate (N2H4·H2O) represents a promising hydrogen storage/production technology. A rational design of advanced N2H4·H2O decomposition catalysts requires an overall consideration of intrinsic activity, number, and accessibility of active sites. We herein report the synthesis of a hierarchically nanostructured NiPt/N-doped carbon catalyst using a three-step method that can simultaneously address these issues. The chelation of metal precursors with polydopamine and thermolysis of the resulting complexes under reductive atmosphere resulted in a concurrent formation of N-doped carbon substrate and catalytically active NiPt alloy nanoparticles. Thanks to the usage of a silica nanosphere template and dopamine precursor, the N-doped carbon substrate possesses a hierarchical macroporous-mesoporous architecture. This, together with the uniform dispersion of tiny NiPt nanoparticles on the carbon substrate, offers opportunity for creating abundant and accessible active sites. Benefiting from these favorable attributes, the NiPt/N-doped carbon catalyst enables a complete and rapid hydrogen production from alkaline N2H4·H2O solution with a rate of 1602 h-1 at 50 °C, which outperforms most existing catalysts for N2H4·H2O decomposition.

Noble-Metal-Free Ni-W-O-Derived Catalysts for High-Capacity Hydrogen Production from Hydrazine Monohydrate.

Development of active and earth-abundant catalysts is pivotal to render hydrazine monohydrate (N2H4·H2O) viable as a hydrogen carrier. Herein, we report the synthesis of noble-metal-free Ni-W-O-derived catalysts using a hydrothermal method in combination with reductive annealing treatment. Interestingly, the thus-prepared Ni-based catalysts exhibit remarkably distinct catalytic properties toward N2H4·H2O decomposition depending upon the annealing temperature. From a systematic phase/microstructure/chemical state characterization and the first-principles calculations, we found that the variation of the apparent catalytic properties of these Ni-based catalysts should stem from the formation of different Ni-W alloys with distinct intrinsic activity, selectivity, and distribution state. The thereby chosen Ni-W alloy nanocomposite catalyst prepared under an optimized condition showed high activity, nearly 100% selectivity, and excellent stability toward N2H4·H2O decomposition for hydrogen production. Furthermore, this noble-metal-free catalyst enables rapid hydrogen production from commercially available N2H4·H2O solution with an intriguingly high hydrogen capacity of 6.28 wt % and a satisfactory dynamic response property. These results are inspiring and momentous for promoting the use of the N2H4·H2O-based H2 source systems.

Morphologies Transformation of BODIPY-Based Main Chain Supramolecular Polymers Amphiphiles: From Helical Nanowires to Nanosheets.

The aggregate morphologies of 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) main chain supramolecular polymer amphiphiles (SPA) are tunable by a fine balance of different non-covalent interactions. When the BODIPY segments and sodium cholate are mixed in aqueous solution, they form SPA by electrostatic attraction and hydrogen-bonds. This SPA displays helical nanowires' morphology. After the third component dimeric ß-cyclodextrin (ß-CD-C) is added, the hydrogen bonds between the cholate are substituted by the host-guest interaction between cholate and ß-CD-C. Therefore, these SPA transform their aggregate morphologies into nanosheets' architecture. Therefore, a simple and effective way to regulate self-assembly by non-covalent forces is developed. This supramolecular method may provide an effective way to prepare various nanostructures in aqueous solution and show promising application in the future.

Evaluation of hepatotoxicity potential of a potent traditional Tibetan medicine Zuotai.

ETHNOPHARMACOLOGICAL RELEVANCE: Zuotai (gTso thal) has a long history in the treatment of cardiovascular disease, liver and bile diseases, spleen and stomach diseases as a precious adjuvant in Tibetan medicine. However, Zuotai is a mercury preparation that contains 54.5% HgS. Its application has always been controversial. AIM OF THE STUDY: To evaluate the toxicological effects of Zuotai in hepatocytes and in zebrafish. MATERIALS AND METHODS: MTT was used to determine the survival rate of hepatocytes; Hoechst and TUNEL staining were used to detect the apoptosis cells; Western blot and RT-qPCR assay were used to determine the expression levels of the protein and mRNA; Liver morphology observation and H&E staining were used to evaluate the hepatotoxicity of Zuotai in Zebfrafish. RESULTS: The survival rate of L-02 cells, HepG2 cells and RBL-2A cells reduced by Zuotai (10-4-0.1 mg/mL) in a dose and time-dependent manner. Zuotai (0.1 mg/mL) induced HepG2 cells shrinkage, condensation and fragmentation and increased the number of apoptosis cells. The protein expression levels of cleaved Caspase-3 and Bax were increased and the expression levels of Bcl-2 were reduced after HepG2 cells exposed to Zuotai (10-4-0.1 mg/mL) for 24 h. In addition, Zuotai (0.2 mg/mL) induced the darker liver color of the larval zebrafish and changed the liver morphologic of adult zebrafish. Zuotai (0.2 mg/mL) also increased the mRNA levels of CYP1A1, CYP1B1 and MT-1 in the liver of adult zebrafish. However, no significantly hepatotoxicity was observed after hepatocytes and zebrafish exposed to HgS at the same dose. CONCLUSIONS: Results showed that Zuotai induced hepatotoxicity effectively under a certain dose but its hepatotoxicity likely occurs via other mechanisms that did not depend on HgS.

A fluorescent, photochromic and thermochromic trifunctional material based on a layered metal-viologen complex.

The azide anion as an energy acceptor and an electron donor has been introduced into a metal-viologen compound to form a 2D layered viologen-based trifunctional material, which exhibits the rare discolored function of reversible photochromism and thermochromism. Interestingly, its fluorescence can be switched by visible light irradiation and heating in air.