Metal nanoclusters (NCs) have emerged as novel antibacterial agents featuring broad-spectrum antibacterial activity without drug resistance for bacteria, but suffer from fast antibacterial invalidation due to their consumption by bacteria. Herein we report the design of a visible-light-driven photodynamic antibacterial agent based on conjugating aggregation-induced emission (AIE)-featured AuAg NCs with highly luminescent carbon dots (CDs). The conjugation of CDs with AuAg NCs could not only enhance the visible-light harvest, but also promote charge carrier generation/separation charge/energy transfer, leading to the production of abundant reactive oxygen species (ROS) for bacterial killing under visible-light irradiation.
View Article and Find Full Text PDFLong-lasting yet visible-light-driven bacterial inhibition is highly desired for environmental protection and public health maintenance. However, conventional semiconductors such as titanium dioxide (TiO) are impotent for such antibacterial application due to their low utilization rate for visible light. Herein we report the design of a long-lasting yet visible-light-driven antibacterial agent based on marrying luminescent Au nanoclusters (Au NCs for short) to TiO (TiO-NH@Au NCs).
View Article and Find Full Text PDFA mechanistic study on the two-phase synthesis of heteroleptic Au nanoclusters (NCs) is reported here. First, the effects of binary ligands on controlling the size of Au NCs were examined: (1) the binary ligands could exhibit an eclectic effect on the size control of Au NCs if the binding affinities of such hetero-ligands with Au are comparable and (2) the binary ligands could exhibit a competitive effect on the size control of Au NCs, and the size of the Au NCs could be determined by the ligand with stronger binding affinity to Au. This finding is interesting and can shed some light on the design of new functional metal NCs.
View Article and Find Full Text PDFThe two-phase Brust-Schiffrin (B-S) method has been widely used for synthesizing small-sized Au nanoparticles (NPs) of size 2-6 nm, as well as Au nanoclusters (NCs) of size <2 nm. However, size tuning of Au NCs at the atomic level by this method is challenging probably due to a lack of in-depth understanding of its mechanism. Herein, we report the identification of two roles of tetraoctylammonium bromide (TOAB) in the two-phase B-S method: TOAB not only transfers Au(iii) precursors but also transfers the reducing agent NaBH from the aqueous to the organic phase.
View Article and Find Full Text PDFThe subtle structural change of hydrophilic ligands on the size control of metal nanoclusters (NCs) is unclear but critically important for fundamental understanding. Herein, we report our findings that subtle changes of isomeric ligands lead to a dramatic difference in the size of water-soluble Au NCs. By using isomeric para-mercaptobenzoic acid (p-MBA), m-MBA, and o-MBA as model ligands, it was found that both the steric hindrance and the electronic effect of isomeric ligands significantly influences the size of Au NCs, resulting in the formation of different sized Au44(p-MBA)26 NCs, Au25(m-MBA)18 NCs, and Au37/43(o-MBA)22/26 NCs.
View Article and Find Full Text PDFThe remodelling of structural and functional neurovascular unit (NVU) becomes a central therapeutic strategy after cerebral ischaemic stroke. In the present study, we investigated the effect of combined therapy of sodium ferulate (SF), n-butylidenephthalide (BP) and adipose-derived stromal cells (ADSCs) to ameliorate the injured NVU in the photochemically induced thrombotic stroke in rats. After solely or combined treatment, the neovascularization, activation of astrocytes, neurogenesis, expressions of vascular endothelial growth factor (VEGF) and claudin-5 were assessed by immunohistochemical or immunofluorescence staining.
View Article and Find Full Text PDFAn efficient cross-coupling of sodium or lithium sulfinates with aryl iodides, using a combination of nickel and photoredox catalysis, is described. The dual catalyst system enables a versatile synthesis of aryl sulfones at room temperature in good yields and displays a broad functional group compatibility. The potential utility of this method in the late-stage diversification of complex molecules and in the conversion of organolithium reagents and sulfur dioxide into sulfones is demonstrated.
View Article and Find Full Text PDFMolecules containing a sulfonyl functionality, such as sulfones, sulfonyl chlorides or sulfonamides play an important role in organic chemistry and have found widespread application, especially in the construction of biologically active compounds. Recently, methods for the synthesis of the sulfonyl moiety utilizing sulfur dioxide as a key building block have received considerable attention. In this context, radical-based transformations with sulfur dioxide have emerged as a new and attractive approach for the construction of the sulfonyl functional group.
View Article and Find Full Text PDFThe synthesis of sulfones via a selective functionalization of C-H-bonds represents a powerful alternative to classical methods for the preparation of this important compound class. Within the last decade, significant progress has been made in this field. This review highlights recent advances in the area of metal-catalyzed as well as metal-free transformations for the direct sulfonylation of C(sp)-H and C(sp)-H bonds.
View Article and Find Full Text PDFPhotochemically induced cerebral ischemia is an easy-manipulated, reproducible, relatively noninvasive, and lesion controllable model for translational study of ischemic stroke. In order to longitudinally investigate the characterization of the model, magnetic resonance imaging, F-2-deoxy-glucose positron emission tomography, fluorescence, and bioluminescence imaging system were performed in correlation with triphenyl tetrazolium chloride (TTC), hematoxylin-eosin staining, and immunohistochemistry examinations of glial fibrillary acidic protein, CD68, NeuN, von willebrand factor, and α-smooth muscle actin in the infarct zone. The results suggested that the number of inflammatory cells, astrocytes, and neovascularization significantly elevated in peri-infarct region from day 7 and a belt of macrophage/microglial and astrocytes was formed surrounding infarct lesion at day 14.
View Article and Find Full Text PDFBeing a potential candidate for stroke treatment, bone marrow-derived mesenchymal stem/stromal cells (BM-MSCs) have been demonstrated to be able to enhance angiogenesis and proliferation of reactive astrocytes, which subsequently leads to the amelioration of neurological injury. Increasing evidence further indicates that combining BM-MSCs with certain agents, such as simvastatin, may improve therapeutic effects. Sodium ferulate (SF) and n-butylidenephthalide (BP), two main components of Radix Angelica Sinensis, are proven to be important regulators of stem cells in cell migration, differentiation, and pluripotency maintenance.
View Article and Find Full Text PDFBackground: Studies have indicated that bone marrow stromal cell (BMSC) administration is a promising approach for stroke treatment. For our study, we chose sodium ferulate (SF) and n-butylidenephthalide (BP) combined with BMSC, and observed if the combination treatment possessed more significant effects on angiogenesis and neurogenesis post-stroke.
Methods: We established rat permanent middle cerebral artery occlusion (MCAo) model and evaluated ischemic volumes of MCAo, BMSC, SF + BP, Simvastatin + BMSC and SF + BP + BMSC groups with TTC staining on the 7th day after ischemia.
1,2-Bis(trimethylsilyl)benzenes are key starting materials for the synthesis of benzyne precursors, Lewis acid catalysts, and certain luminophores. We have developed efficient, high-yield routes to functionalized 4-R-1,2-bis(trimethylsilyl)benzenes, starting from either 1,2-bis(trimethylsilyl)acetylene/5-bromopyran-2-one (2) or 1,2-bis(trimethylsilyl)benzene (1)/bis(pinacolato)diborane. In the first reaction, 5 (R = Br) is obtained through a cobalt-catalyzed Diels-Alder cycloaddition.
View Article and Find Full Text PDFObjective: To observe the effect of Yinian Jiangya Yin (Decoction for lowering blood pressure to prolong life) on patients with early hypertension and its mechanism on the function of vascular endotheliocytes.
Methods: The 79 patients with early primary hypertension belonging to the TCM syndrome of stagnation of phlegm and blood stasis in meridians and hyperactivity of the liver-yang were randomly divided into a treatment group of 40 patients treated with Yinian Jiangya Yin and a control group of 39 patients treated with Tianma Gouteng Yin (Decoction of Gastrodia and Uncaria). The changes in score of TCM syndrome and in blood pressure before and after treatment were observed in the two groups.
Zhongguo Zhong Xi Yi Jie He Za Zhi
January 2010
Objective: To observe the effects of Yinian Jiangya (YNJY) Decoction contained serum on cell proliferation of primary cultured endothelial cells of spontaneously hypertensive rat (SHR) and the peroxisome proliferator-activated receptor-gamma (PPAR-gamma) mRNA expression in the cells.
Methods: SD rats were fed with high-lipid diet and different doses (high, medium and low, containing crude drug of 5.2 g/mL, 2.