Visible Light and Microwave-Mediated Rapid Trapping and Release of Singlet Oxygen Using a Coordination Polymer.

Due to its high reactivity and oxidative strength, singlet oxygen (1 O2 ) is used in a variety of fields including organic synthesis, biomedicine, photodynamic therapy and materials science. Despite its importance, the controlled trapping and release of 1 O2 is extremely challenging. Herein, we describe a one-dimensional coordination polymer, CP1, which upon irradiation with visible light, transforms 3 O2 (triplet oxygen) to 1 O2 . CP1 consists of CdII centers bridged by 9,10-bis((E)-2-(pyridin-4-yl)vinyl)anthracene ligands which undergo a [4+2] cycloaddition reaction with 1 O2 , resulting in the generation of CP1-1 O2 . Using microwave irradiation, CP1-1 O2 displays efficient release of 1 O2 , over a period of 30 s. In addition, CP1 exhibits enhanced fluorescence and has an oxygen detection limit of 97.4 ppm. Theoretical calculations reveal that the fluorescence behaviour is dominated by unique through-space conjugation. In addition to describing a highly efficient approach for the trapping and controlled release of 1 O2 , using coordination polymers, this work also provides encouragement for the development of efficient fluorescent oxygen sensors.

Host-Guest Assembly-Crosslinked Nanoemulsions with Dual-Antimicrobial Mechanism for Treating Multidrug-Resistant Bacterial Biofilms.

Plant essential oils have good antimicrobial properties, but their poor stability and compatibility in aqueous solutions greatly limit their practical application. To address this issue, a dynamically crosslinked nanoemulsion based on host-guest assembly was developed in this study. First, a ß-cyclodextrin-functionalized quaternary ammonium surfactant (ß-CD-QA) and adamantane-terminated polyethylene glycol (APA) crosslinker were first synthesized. Then, the oil-in-water host-guest crosslinked nanoemulsions (HGCTNs) were formed by incorporating tea tree essential oils (TTO) as a natural antimicrobial agent. The results showed that HGCTNs significantly improved the stability of the essential oil nanoemulsions and extended their shelf life. Furthermore, HGCTNs demonstrated effective antimicrobial properties against both Gram-negative/positive bacterioplankton and bacterial biofilms. The results of antibacterial experiments showed that the dynamically crosslinked HGCTNs exhibit superior antibacterial efficacy, with a minimum inhibitory concentration (MIC) of 12.5 v/v % (0.13 µL/mL TTO) and could eradicate the biofilms. The electrical conductivity of the bacterial solution gradually increased within 5 h of treatment with the nanoemulsions, indicating that the HGCTNs have a slow-release effect of TTO and sustainable antibacterial ability. The antimicrobial mechanism can be attributed to the synergistic antibacterial action of the ß-CD-QA surfactant containing a quaternary ammonium moiety and TTO, which are stabilized by nanoemulsions.

Phase Transition-Promoted Rapid Photomechanical Motions of Single Crystals of a Triene Coordination Polymer.

Molecular crystals with the ability to transform light energy into macroscopic mechanical motions are a promising class of materials with potential applications in actuating and photonic devices. In regard to such materials, coordination polymers that exhibit dynamic photomechanical motion, associated with a phase transition, are unknown. Herein, we report an intriguing photoactive, one-dimensional ZnII coordination polymer, 1, derived from 1,3,5-tri-4-pyridyl-1,2-ethenylbenzene and 3,5-difluorobenzoate. Single crystals of 1 under UV light irradiation exhibit rapid shrinking and bending, violent bursting-jumping, splitting, and cracking behavior. Single-crystal X-ray diffraction analysis and 1 H NMR spectroscopy reveal an unusual photoinduced phase transition involving a single-crystal-to-single-crystal [2+2] cycloaddition reaction that results in photomechanical responses. Interestingly, crystals of 1, which are triclinic with space group P 1 ‾ ${P\bar{1}}$ , are transformed into a higher symmetry, monoclinic cell with space group C2/c. This process represents a rare example of symmetry enhancement upon photoirradiation. The photomechanical activity is likely due to the sudden release of stress associated with strained molecular geometries and significant solid-state molecular movement arising from cleavage and formation of chemical bonds. A composite membrane fabricated from 1 and polyvinyl alcohol (PVA) also displays interesting photomechanical behavior under UV light illumination, indicating the material's potential as a photoactuator.

Photopolymerization-Driven Macroscopic Mechanical Motions of a Composite Film Containing a Vinyl Coordination Polymer.

We report a unique vinyl coordination polymer (CP), [Zn(4-Fb)2 (tkpvb)]n (1, 4-HFb=4-fluorobenzoic acid, tkpvb=1,2,4,5-tetrakis(4-pyridylvinyl)benzene) that undergoes a rare photopolymerization reaction to form a two-dimensional CP integrated with a one-dimensional linear organic polymer. Upon light irradiation at different wavelengths, 1 exhibits an unprecedented phenomenon of photoinduced nonlinear lattice expansion. 1 can be uniformly dispersed in polyvinyl alcohol (PVA) to form the composite film of 1-PVA. When this film is exposed to UV light, internal minute stresses within crystallites are released by lattice expansion, resulting in a variety of photopolymerization-driven macroscopic mechanical motions. The findings provide new insights into the conversion of small lattice expansions of CPs into macroscopic mechanical motions based on photopolymerization reactions, which can promote the development of CPs-based smart photoactuators in the burgeoning field of microrobotics.

Efficacy and safety of drug-coated balloon in the treatment of acute myocardial infarction: a meta-analysis of randomized controlled trials.

Acute myocardial infarction (AMI) is one of the main causes of death in the world, and the incidence of AMI is increasing in the young population. Drug-coated balloon (DCB) has become an effective concept for the treatment of in-stent restenosis, small vessel disease, bifurcation lesions, high blood risk conditions, and even de novo large vessel disease. To ensure whether DCB can play an alternative role in AMI, we conducted a comprehensive meta-analysis of randomized controlled trials (RCTs) to evaluate the efficacy and safety of DCB in the treatment of AMI. Electronic databases were searched for RCTs that compared DCB with stent for AMI. The primary outcome was major adverse cardiac events (MACEs), the secondary outcome was late lumen loss (LLL). RevMan 5.3 software and RStudio software were used for data analysis. Five RCTs involving 528 patients with 6-12 months of follow-up were included. There was no significant difference in the incidence of MACEs between DCB group and stent group (RR, 0.85; 95% CI 0.42 to 1.74; P = 0.66). Lower LLL was shown in DCB group (WMD, - 0.29; 95% CI - 0.46 to - 0.12; P < 0.001). This meta-analysis of RCT showed that DCB might provide a promising way on AMI compared with stents. Rigorous patients' selection and adequate predilation of culprit lesions are necessary to optimize results and prevent bailout stent implantation.PROSPERO registration number: CRD42020214333.

Protective Mechanism of Common Buckwheat (Fagopyrum esculentum Moench.) against Nonalcoholic Fatty Liver Disease Associated with Dyslipidemia in Mice Fed a High-Fat and High-Cholesterol Diet.

This study aimed to investigate the protective mechanism of common buckwheat (Fagopyrum esculentum Moench.) against nonalcoholic fatty liver disease (NAFLD) associated with dyslipidemia in mice that were fed a high-fat and high-cholesterol diet (HFD). Results showed that oral supplementation of common buckwheat significantly improved physiological indexes and biochemical parameters related to dyslipidemia and NAFLD in mice fed with HFD. Furthermore, the HFD-induced reductions in fecal short-chain fatty acids were reversed by common buckwheat intervention, which also increased the fecal bile acid (BA) abundance compared with HFD-induced hyperlipidemic mice. Liver metabolomics based on ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry demonstrated that common buckwheat supplementation made significant regulatory effects on the pentose phosphate pathway, starch and sucrose metabolism, primary BA biosynthesis, and so forth. The results of high-throughput sequencing revealed that common buckwheat supplementation significantly altered the structure of the intestinal microbiota in mice fed with HFD. The correlations between lipid metabolic parameters and intestinal microbial phylotypes were also revealed by the heatmap and network. Additionally, common buckwheat intervention regulated the mRNA expressions of genes responsible for liver lipid metabolism and BA homeostasis, thus promoting BA synthesis and excretion. These findings confirmed that common buckwheat has the outstanding ability of improving lipid metabolism and could be used as a potential functional food for the prevention of NAFLD and hyperlipidemia.

The protective mechanism of Lactobacillus plantarum FZU3013 against non-alcoholic fatty liver associated with hyperlipidemia in mice fed a high-fat diet.

Lactobacillus plantarum FZU3013, a probiotic previously isolated from the traditional brewing process of Hongqu rice wine, may have the beneficial effect of improving the disorders of lipid metabolism. This study aimed to investigate the role of L. plantarum FZU3013 in improving non-alcoholic fatty liver (NAFL) associated with hyperlipidemia in mice fed a high-fat diet. The results indicated that L. plantarum FZU3013 intervention significantly reduced the HFD-induced body weight gain and the abnormal levels of serum total triglycerides (TG), total cholesterol (TC) and low-density lipoprotein (LDL-C), and inhibited the excessive accumulation of liver lipids. In addition, L. plantarum FZU3013 also promoted the excretion of bile acids through feces. Metagenomic and multivariate statistical analysis revealed that L. plantarum FZU3013 made significant structural changes in the intestinal microbiome of the mice fed with HFD, in particular by modulating the relative abundance of some function related microbial phylotypes. Furthermore, ultra-performance liquid chromatography with quadruple-time of flight mass spectrometry (UPLC-QTOF/MS)-based liver metabolomics demonstrated that L. plantarum FZU3013 had a significant regulatory effect on the composition of liver metabolites in hyperlipidemic mice, especially on the levels of some important biomarkers involved in the pathways of glycerophospholipid metabolism, fatty acid degradation, fatty acid elongation, glycerolipid metabolism, primary bile acid biosynthesis, arachidonic acid metabolism, etc. Moreover, L. plantarum FZU3013 regulated the mRNA expression levels of the genes responsible for liver lipid and cholesterol metabolism. L. plantarum FZU3013 intervention increased the hepatic mRNA levels of cholesterol 7α-hydroxylase (CYP7A1) and the bile salt export pump (BSEP), suggesting enhanced bile acid synthesis and excretion from the liver. These findings present new evidence supporting that L. plantarum FZU3013 has the potential to improve lipid metabolism disorders through modulating specific intestinal microbial phylotypes and regulating hepatic lipid metabolism related genes, therefore it could be used as a potential functional food for the prevention of NAFL and hyperlipidemia.