Latest ArticlesDownregulated pro-apoptotic protein in cancer cells compromises the chemotherapy by a cytotoxic drug. Here, we report co-delivery of a pro-apoptotic protein, caspase 3 (Cas 3), and cytotoxic agent, oridonin (ORD), for synergistic cancer treatment, using a method of liposome-based anchoring and core encapsulation. First, ORD is modified with hyaluronic acid (HA) to improve its solubility. Then, the targeted co-delivery system is prepared by assembling the conjugate HA-ORD onto the Cas 3-loaded liposomes, which the surface HA can target the CD44 receptor on cancer cells. In vitro, the co-loaded liposomes (120 nm) are specifically taken up by 4T1 cells and endow a 1.5-fold increase of Cas 3. After intravenous injection into the tumor-bearing mice, the liposomes accumulate in the tumor with high efficacy and significantly inhibit tumor growth via promoting apoptosis and anti-proliferation of cancer cells. Mechanistically, the co-delivery works synergistically by upregulating the activated Cas form, cleaved-Cas 3.
Forrestiacids C (1) and D (2), a pair of C-25 epimeric triterpene–diterpene adducts were isolated from the needles and twigs of the vulnerable conifer Pseudotsuga forrestii. This unprecedented class of compounds might be generated via an intermolecular Michael addition reaction of a rearranged 6/6/5/5-fused spiro-lanostene with an abietene. Their structures were established by spectroscopic data and X-ray crystallography. The adducts showed inhibitory activities against the ATP-citrate lyase (ACL) and acetyl-CoA carboxylase 1 (ACC1), two rate-limiting enzymes in the de novo lipogenesis pathway.
Fluorescent dyes play a crucial role in fluorescence imaging and sensing technology. However, there is a dilemma that they are usually intrinsically hydrophobic which lacks of emission in water and modification with ionic groups to access water solubility may result in poor membrane permeability. Fluorescent dyes with strong fluorescence emission in both nonpolar and polar solvents are highly desirable. In this manuscript, we reported a strategy to develop fluorescent BODIPY dyes via installation of amide moiety at meso position of 1, 3, 5, 7-tetramethyl-BODIPY and discovered that N, N'-dialkylsubstituted BODIPY amides possessed highly fluorescent emission with favorable environment-insensitive properties.
Two unprecedented polycyclic spirooliganones C and D (1 and 2) with a novel spiro[bicyclo[2.2.2]octane-2, 2′-bicyclo[3.1.0]hexane] carbon skeleton, one known dimeric prenylated C6C3 compound (3), and a pair of new enantiomeric prenylated C6C3 compounds (+)-5 and (−)-5 together with their direct precursors (+)-4 and (−)-4 were isolated from the roots of Illicium oligandrum. Their structures and absolute configurations were elucidated by spectroscopic analysis, single crystal X-ray diffraction data, and electronic circular dichroism calculations. A possible biosynthetic pathway for compounds 1 and 2 involving the Diels-Alder reaction between (−)-sabinene and cyclic prenylated tetrahydropyrano-type C6C3 compounds was proposed. The characteristic prenylated C6C3 compounds (+)-4 and (−)-4 were separated on a chiral stationary phase and their absolute configurations were determined by calculated ECD for the first time. In the antiviral bioassays, compounds 1 and (+)-5 exhibited significant inhibitory activity against CVB3 with IC50 values of 11.11 µmol/L and 1.11 µmol/L, respectively. Compounds 1 and 2 also showed moderate inhibition against influenza A (H1N1) virus.
Well-developed mitochondria-targeted nanocarriers for function regulation are highly desirable. Numerous studies have been conducted on the treatment of mitochondria-related diseases; however, further improvements are required to develop more effective drug delivery methods. Herein, we comprehensively introduce recent developments progress in rational design of mitochondria-targeted nanocarriers, and discuss the different strategies of available nanocarriers for targeting mitochondria. We also highlight the advantages and disadvantages of various carrier systems that are currently in use. Finally, perspective on new generation for mitochondria-targeted delivery systems in the emerging area of drug-based therapeutics is also discussed.
The tuning of olefin-polymerization catalyst properties through ligand modifications is efficient but requires complicated and costly syntheses. In this contribution, a simple Bu2Mg-based cocatalyst strategy is designed that can simultaneously enhance the catalytic properties (activity, thermal stability, polymer molecular weight, branching density, melting point, etc.) of various nickel catalysts (α-diimine nickel, pyridine imine nickel and iminopyridine-N-oxide nickel) in ethylene polymerization, and enable great product morphology control. For example, a simple α-diimine nickel catalyst can demonstrate polymerization activity of up to 1.29 × 107 g mol−1 h−1 and molecular weight of up to 1.90 × 106 g/mol in the presence of Bu2Mg cocatalyst. The resulting polyethylenes exhibit excellent mechanical properties, with tensile stress of up to 47.4 MPa and strain of up to 1020%. This cocatalyst strategy is generally applicable to different nickel catalysts, and can lead to property enhancement in ethylene copolymerization with a series of polar comonomers such as methyl 10-undecylenate, 10-undecylenic acid and 10-undecenol.
Although targeted therapy and immunotherapy are now shining in the treatment of some cancers, chemotherapy is still the cornerstone of drug treatment for many cancer patients. The emergence of chemotherapy prodrugs can improve the drug activity and reduce the side effects of chemotherapy. When used, the tumor microenvironment has characteristics different from normal tissues, and the existence of the microenvironment provided a more convenient way to design responsive nanodrugs. Herein, we designed a glutathione (GSH)-responsive prodrug nanogels for enhancing tumor chemotherapy. In the nanogels of HHNP, 10-hydroxycamptothecin (HCPT) played an essential role in killing cancer cells. HCPT was jointed with a cross-linker agent with disulfide bond and was further coated with polyethylene glycol, which not only prolonged the half-life of the drug, but also made HCPT accurate transport to the tumor fractions and achieved precise and controllable release. The proposal of HHNP effectively retained the biological activity of the drug, and introduced functions such as targeting, selective release and biodegradation, which greatly improved the medical efficiency of the drug and effectively reduced the toxic and side effects. This chemotherapeutic prodrug nanogel offers a new window for constructing efficient drug delivery platform.
Corneal wound closure for surgical eye surgeries or accidents is typically performed to prevent pathogens from the sterile intraocular environment and avoid potential postoperative complications. Tissue adhesives are increasingly employed for corneal wound closure with superior treatment efficiency and less adverse effects. In this study, we successfully develop a novel corneal adhesive based on functionally coupled PEG-lysozyme (PEG-LZ) hydrogels for wound closure after surgical eye surgeries. PEG-LZ hydrogels have plenty of micropores and gradually decreased pore size with increasing concentration from 10%, 15% to 20% (w/v), in which PEG-LZ (15%) represents the suitable pH value, gelation time and elastic modulus. PEG-LZ hydrogels have no in vitro cytotoxicity and excellent ex vivo wound closure effectiveness in porcine eyes. The in vivo wound sealant in rabbit eyes by PEG-LZ hydrogels presents a superior therapeutic effect compared with the conventional methods of stromal hydration and suture, in terms of the wound closure percent, mean corneal thickness, percent of wound gaping, and the Descemet membrane detachment. PEG-LZ hydrogels do not induce obvious histological pathology changes. The PEG-LZ corneal adhesive is considered as a tissue adhesive alternative for wound closure after surgical eye surgeries.
To develop efficient concerted companion (CC) dyes for fabricating high-performance DSSCs, three organic dyes XL1-XL3 have been designed by varying the position and number of the β-hexylthiophene (HT) bridges, and these organic dye units are covalently linked with our previously reported porphyrin dye XW10 to construct the corresponding CC dyes XW74-XW76. Among the organic dyes, XL3 contains two β-hexylthiophene units at both the donor and acceptor parts and thus possesses stronger light-harvesting capability in the green light region. Because of the most complementary absorption between XL3 and XW10 as well as the excellent photovoltaic behavior of the individual XL3 dye, the corresponding CC dye XW76 affords the best PCE (10.78%) among all the CC dyes. Upon coadsorption with CDCA, XW76 affords a highest PCE of 11.35%, which outperforms the previous cosensitization system of XW10+WS-5. This work provides an approach for developing efficient DSSCs based on CC dyes composed of an organic dye unit with suitable π spacers inserted at appropriate positions.
Relying on the electron energy loss spectrum (EELS) of metallic elements to obtain microstructure analysis is an investigation method of the reaction mechanisms of transition metal oxides (TMOs) in catalysis, energy storage and conversion. However, the low signal from K shell owing to insufficient electron beam energy, and the complicated electronic structure in L shell of the metal element restrict the analysis of the coordination environment of the TMOs. Herein, density functional theory (DFT) calculation, Fourier transform (FT) and wavelet transform (WT) were employed to probe the relationship between the four individual peaks in O K-edge spectra of iron oxides and the microstructure information (chemical bonds and atomic coordination). The findings show that the peak amplitude ration is in a linear correlation with the valence state of Fe element, and that the coordination number obtained by radial distribution function (RDF) is favorably linearly correlative with that from the standard coordination structure model. As a result, the quantitative analysis on the change of valence state and atomic coordination in microstructure can be realized by EELS O K-edge spectra. This study establishes EELS O K-edge spectrum as a promising pathway to quantitatively analyze the valence state and atomic coordination information of TMOs, and offers an effective method to conduct microstructure analysis via the EELS spectra of the non-metal element.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
