Latest ArticlesTumor cell resistance is one of the big hurdles limiting the therapeutic efficacy of tumor necrosis factorrelated apoptosis-inducing ligand (TRAIL)-based cancer treatment. Therefore, the development of a safe and effective sensitizer agent is greatly desired for optimizing TRAIL therapy. Herein, we successfully developed a Se/Fe complex with low toxicity to highly effectively inhibit tumor cells proliferation and migration capabilities through down-regulating ER stress related selenoproteins. Furthermore, it could more efficiently damage tumor spheroids with good penetration capability. More importantly, it could synergize with TRAIL treatment to induce the robust generation of reactive oxygen species (ROS), downregulating ER stress related selenoproteins for triggering tumor cells apoptosis in extrinsic and intrinsic signaling pathways. Taken together, this study provides a potential chemo-drug and sensitizer agent to improve the therapeutic efficacy of TRAIL-based cancer treatment.
About 90% cancer-related mortality results from the cancer metastasis, which generally undergoes after epithelial-mesenchymal transition (EMT) process. N-Cadherin, overexpressed on cancer cell surface during EMT, can enhance the migration of cancer cells. Herein, we design and synthesize a transformable peptide BP-KLVFF-SWTLYTPSGQSK (BFS) that can block N-cadherin for inhibiting cancer migration and metastasis. The peptide BFS consists of three modules including (1) the hydrophobic bis-pyrene (BP) unit for forming and locating nanoparticles, (2) the KLVFF peptide sequence for forming and stabilizing fibrous structures and (3) the targeting peptide sequence SWTLYTPSGQSK that can specifically bind to Ncadherin. The peptide BFS can form nanoparticles in PBS, which can transform to nanofibers when targeting and binding to N-cadherin. The nanofibers inhibit the migration of N-cadherin overexpressed MDA-MB-436 cancer cells. The peptide BFS shows 83.6% inhibiting rate in cells wound healing assay. In addition, the inhibition rate is 67.9% when the BFS applied in transwell migration assay. These results indicate that the BFS has excellent ability to inhibit migration of cancer cells. This self-assembly strategy could be potentially utilized to regulate the key protein during EMT for inhibiting the tumor metastasis.
Herein, a series of carbazolyl cyanobenzene (CCB)-based organic photocatalysts with a broad range of photoredox capabilities were designed and synthesized, allowing precise control of the photocatalytic reactivity for the controllable reduction of aryl halides via a metal-free process. The screened-out CCB (5CzBN), a metal-free, low-cost, scalable and sustainable photocatalyst with both strong oxidative and reductive ability, exhibits superior performance for both dehalogenation and C-C bond-forming arylation reactions.
Unremitting efforts have been intensively making for pursuing the goal of the reversible transition of electrowetting owing to its vital importance to many practical applications, but which remains a major challenge for carbon nanotubes due to the irreversible electrochemical damage. Herein, we proposed a subtly method to prevent the CNT array from electrochemical damage by using liquid medium instead of air medium to form a liquid/liquid/solid triphase system. The dimethicone dynamically refills in CNT arrays after removing of voltage that makes the surface back to hydrophobic, which is an elegant way to not only decrease energy dissipation in electrowetting process but also obtain extra energy in reversible dewetting process. Repeated cycles of in situ experiments showed that more than four reversible electrowetting cycles could be achieved in air. It worth mention that the in situ reversible electrowetting voltage of the dimethicone infused CNT array has been lowered to 2 V from 7 V which is the electrowetting voltage for the pure CNT array. The surface of the dimethicone infused CNT array can maintain hydrophobicity with a contact angle of 145.6° after four cycles, compared with 148.1° of the initial state. Moreover, a novel perspective of theoretical simulations through the binding energy has been provided which proved that the charged CNTs preferred binding with water molecules thereby replacing the dimethicone molecules adsorbed on the CNTs, whereas reconnected with dimethicone after removing the charges. Our study provides distinct insight into dynamic reversible electrowetting on the nanostructured surface in air and supplies a way for precise control of wettability in surface chemistry, smart phase-change heat transfer enhancement, liquid lenses, microfluidics, and other chemical engineering applications.
Baicalin, extracted from traditional Chinese medicine Scutellaria baicalensis Georg, possesses multiple pharmacological activities and has great potential for chronic skin wound repair. However, the poor solubility and lack of suitable vehicles greatly limit its further application. Herein, we proposed a convenient and robust strategy, employing PBS solution as solvent, to enhance the solubility of baicalin. Furthermore, we constructed injectable baicalin/F127 hydrogels to study their application in skin wound treatment. The composition and temperature sensitivity of baicalin/Pluronic® F-127 hydrogels were confirmed by FTIR and rheological testing, respectively. In vitro release measurement indicated that the first order model was best fitted with the release profile of baicalin from hydrogel matrix. Besides, MTT assay, AO/EO staining assay as well as hemolytic activity test revealed the excellent cytocompatibility of baicalin/F127 hydrogels. Antioxidant activity assay demonstrated the cytoprotective activity of baicalin/ F127 hydrogels against reactive oxygen species (ROS). Furthermore, the in vivo experiments exhibited the ability of baicalin/F127 hydrogel to accelerate wound healing. In conclusion, this novel injectable baicalin/F127 hydrogel should have bright application for chronic wound treatment.
Herein, we have presented a novel and easy to operate seed-mediated system for fabricating gold bipyramids (AuBPs) with 85% yields without any separation/purification processes. The used gold seeds are reduced by tannin and citrate, two kinds of air stable ligands, and conventionally employed unstable NaBH4 are thoroughly cast off. In addition, the as-proposed gold seeds can also be employed for AuNRs fabrication with rather larger diameters (22.2-60.3 nm), which is difficult to be achieved by conventional seed mediated fabrication system.
Accurate temperature measurement plays an important role in a variety of industrial processes and scientific researches. In our work, the dual-mode temperature response nanoprobe CDs-Tb-TMPDPA containing a two-photon ligand (4-(2, 4, 6-trimethoxyphenyl)-pyridine-2, 6-dicarboxylic acid, TMPDPA) sensitized Tb3+ as a temperature-sensitive unit and carbon dots (CDs) as photothermal reagent and a fluorescence reference unit, have been designed and synthesized. In this system, both the fluorescence intensity ratio and the fluorescence lifetime have a good response to temperature. In addition, due to the excellent photothermal conversion capability of CDs, photothermal antibacterial ability was also tested. Based on the temperature dependence of the fluorescence and the two-photon excitation characteristics of CDs-Tb-TMPDPA, the nanoprobe can also be used in the anti-counterfeiting. Our finding opens a new prospect for the use of two-photon sensitized dual-mode fluorescence thermometers.
Anodic electrocatalyst plays the core role in direct alcohol fuel cells (DAFCs), while traditional Pt-catalysts suffer from limited catalytic activity, high over potential and severe CO poisoning. Herein, by selectively depositing Rh atoms on the defective-sites of Pt nanowires (NWs), we developed a new Pt@Rh NW electrocatalyst that exhibited enhanced electrocatalytic performance for both methanol oxidation (MOR) and ethanol oxidation (EOR). Both cyclic voltammetry (CV) and in-situ infrared spectroscopy revealed that the presence of Rh atoms suppressed the generation of poisonous intermediates and completely oxidized alcohols molecule into CO2. Atomic resolusion spherical aberration corrected high-angle annular dark field scanning transmission electron microscopy (CS-HAADF-STEM) and energy-dispersive X-ray spectroscopy (EDS) mapping analysis revealed that Rh atoms were primarily deposited on the defective sites of Pt NWs. Meanwhile, the presence of Rh atoms also modified the electronic state of Pt atoms and therefore lowered the onset potential for alcohols oxidation potential. This work gives the first clear clue on the role of the defective sites of Pt nanocatalyst poisoning, and propose that selectively blocking these sites with trace amount of Rh is an effective strategy in designing advantageous electrocatalysts.
Great success has been witnessed in last decades, some new techniques and strategies have been widely used in drug discovery. In this roadmap, several representative techniques and strategies are highlighted to show recent advances in this filed. (A) A DOX protocol has been developed for accurate protein-ligand binding structure prediction, in which first principle method was used to rank the binding poses. Validation against crystal structures have found that DOX prediction achieved an impressive success rate of 99%, indicating significant improvement over molecular docking method. (B) Virtual target profiling is a compound-centric strategy enabling a parallel implementation of interrogating compounds against various targets in a single screen, which has been used in hit/lead identification, drug repositioning, and mechanism-of-action studies. Current and emerging methods for virtual target profiling are briefly summarized herein. (C) Research on targeted autophagy to treat diseases has received encouraging progress. However, due to the complexity of autophagy and disease, experimental and in silico methods should be performed synergistically for the entire process. This part focuses on in silico methods in autophagy research to promote their use in medicinal research. (D) Histone deacetylases (HDACs) play important roles in various biological functions through the deacetylation of lysine residues. Recent studies demonstrated that HDACs, which possess low deacetylase activities, exhibited more efficient defatty-acylase activities. Here, we review the defatty-acylase activity of HDACs and describe examples for the design of isoform selective HDAC inhibitor. (E) The FDA approval of three kinase allosteric inhibitors and some others entering clinical study has spurred considerable interests in this targeted drug discovery area. (F) Recent advances are reviewed in structure-based design of novel antiviral agents to combat drug resistance. (G) Since nitric oxide (NO) exerts anticancer activity depending on its concentration, optimal levels of NO in cancer cells is desirable. In this minireview, we briefly describe recent advances in the research of NO-based anticancer agents by our group and present some opinions on the future development of these agents. (H) The field of photoactivation strategies have been extensively developed for controlling chemical and biological processes with light. This review will summarize and provide insight into recent research advances in the understanding of photoactivatable molecules including photoactivatable caged prodrugs and photoswitchable molecules.
Amphiphilic block copolymers poly(ethylene glycol)-block-poly(N-3-(methylthio)propyl glycine) (PEG-b-PMeSPG) were synthesized via ring-opening polymerization of N-3-(methylthio)propyl glycine N-thiocarboxyanhydride (MeSPG-NTA) initiated by amino-terminated PEG. The self-assemblies of three PEG-b-PMeSPG copolymers with different PMeSPG block lengths were first prepared by nanoprecipitation method using THF and DMF, respectively, as the organic solvent, and their morphologies were studied by Cryo-EM and DLS. To prepare polymersomes loaded with glucose oxidase (GOx), double emulsion method followed by extrusion treatment was employed. The oxidation-responsive disruption of polymersomes was achieved upon the introduction of glucose because of the oxidants generated in-situ by GOx/glucose.