Latest ArticlesOxidative therapies receive a limited antitumor efficiency due to the insufficient reactive oxygen species (ROS) levels at focal sites and the evolvement of antioxidant defense systems. Herein, we develop an albumin-based nanomedicine to co-deliver chlorin e6 (Ce6) and COH-SR4 (CS), which can simultaneously enhance the yield and lethality of intracellular ROS for amplified photodynamic therapy (PDT). In which, CS acts as both an activator of AMP-activated protein kinase (AMPK) and an inhibitor of glutathione S-transferases (GSTs). Benefiting from it, the prepared HSA-Ce6@COH-SR4 (HCCS) enables positive feedback uptake by promoting AMPK phosphorylation, leading to rapid and extensive tumor accumulation of drugs. As a result, HCCS obviously increases the ROS production to elevate intracellular oxidative stress. Furthermore, HCCS can inhibit GSTs to disturb the antioxidant defense system of tumor cells, intensifying the oxidative damage of ROS. Ultimately, the PDT of HCCS is significantly strengthened by improving the ROS yield and lethality, which greatly declines the proliferation of breast cancer in vivo. This study may open a window in the development of drug co-delivery system for enhanced oxidative therapy of tumors.
Climate change is an important issue facing the world today and carbon reduction has become the focus of attention for all countries. Alternative bio-fuels are an important means to achieve carbon emission reduction. The production of jet fuel precursors from biomass by hydrothermal liquefaction (HTL) has received a lot of attention due to its mild conditions and environmental friendliness. Lignocellulosic biomass and algal biomass are considered as the second and the third generation biomasses as promising raw materials for alternative fuel preparation. Among them, lignocellulosic biomass has been extensively studied due to its wide range of sources and can be divided into one-step HTL and stepwise HTL according to the process method. Algal biomass has been extensively studied experimentally due to its short growth cycle and the fact that it can sequester large amounts of carbon without taking up arable land. In this paper, the feedstock composition of different biomasses is reviewed for the HTL of biomass. A detailed review of the process characteristics, reaction pathways and influencing factors for the HTL production of jet fuel precursors from lignocellulosic biomass and algal biomass is also presented. Theoretical references are provided for further process optimization and bio-crude quality upgrading.
Hexokinase 2 (HK2) is the rate-limiting enzyme in the first step of glycolysis, catalyzing glucose to glucose-6-phosphate, and overexpressed in most cancer cells. HK2 also binds to voltage-dependent anion channel (VDAC) to stabilize the mitochondrial outer membrane, which inhibits cancer cell apoptosis. Therefore, HK2 has become a potential target for cancer treatment. Proteolysis targeting chimeras (PROTACs) are hetero-bifunctional molecules that recruit an E3 ubiquitin ligase to a given substrate protein resulting in its targeted degradation. Many potent and specific PROTACs targeting dissimilar targets have been developed. In this study, an HK2 PROTAC, 4H-5P-M, was developed and induced the degradation of HK2 relying on the ubiquitin-proteasome system. It was found that 4H-5P-M as an effective HK2 degrader induced HK2 degradation in a dose- and time-dependent manner and suppressed the growth of SW480 cells. 4H-5P-M selectively induced HK2 degradation at a lower concentration than other hexokinase isozymes. Moreover, it could suppress glycolysis and accelerate the apoptosis of cancer cells. Therefore, it provided a new insight into the development of anti-tumor drugs.
Tumor vascular normalization has emerged as a promising strategy for synergistic therapy recently. Based on the strategy of “fluorescence turn on-controllable release”, a novel bifunctional candidate was constructed based on previous developed vascular normalization inducer QDAU5, which could self-assemble to form functional enzyme infrared QDAU5 nanoparticles (FEIRQ NPs). Subsequently, biological evaluation demonstrated that the FEIRQ NPs could induce ferroptosis, endoplasmic reticulum stress, and antigen preconditioning and maturation of dendritic cells and CD8+ T cells, leading to excellent antitumor efficacy in the absence of cytotoxic drugs. Additionally, FEIRQ NPs show high fluorescence intensity upon exposure to the β-galactosidase (β-Gal) enzyme expressed in ovarian cancer, enabling real-time monitoring of therapeutic effects. Overall, our findings suggest a prospering strategy to early diagnosis and efficient therapy for ovarian cancer without cytotoxicity.
Weakly-solvated electrolytes (WSEs) utilizing solvents with weak coordination ability offer advantages for low-potential graphite anode owing to their facile desolvation process and anions-derived inorganic-rich solid electrolyte interphase (SEI) film. However, these electrolytes face challenges in achieving a balance between the weak solvation affinity and high ionic conductivity, as well as between rigid inorganic-rich SEI and flexible SEI for long-term stability. Herein, we introduce 1,3-dioxolane (DOL) and lithium bis(trifluoromethanesulfonyl)-imide (LiTFSI) as functional additives into a WSE based on nonpolar cyclic ether (1,4-dioxane). The well-formulated WSE not only preserves the weakly solvated features and anion-dominated solvation sheath, but also utilizes DOL to contribute organic species for stabilizing the SEI layer. Benefitting from these merits, the optimized electrolyte enables graphite anode with excellent fast-charging performance (210 mAh/g at 5 C) and outstanding cycling stability (600 cycles with a capacity retention of 82.0% at room temperature and 400 cycles with a capacity retention of 80.4% at high temperature). Furthermore, the fabricated LiNi0.8Co0.1Mn0.1O2||graphite full cells demonstrate stable operation for 140 cycles with high capacity retention of 80.3%. This work highlights the potential of tailoring solvation sheath and interphase properties in WSEs for advanced electrolyte design in graphite-based lithium-ion batteries.
Citrinsorbicillin A (1), a novel homotrimeric sorbicillinoid, along with two new monomers citrinsorbicillins B (2) and C (3), were isolated from the Coptis chinensis endophyte Trichoderma citrinoviride HT-9 by liquid chromatograph mass spectrometer (LC-MS)-guided strategy. 1 was the first trimeric-example from terrestrial fungi, which possessed a unique carbon skeleton with two bicyclo[2.2.2]octanedione ring connected through an enolated carbon forming by [4 + 2] cycloaddition. Their structures were elucidated by spectroscopic analysis and X-ray diffraction. 1 exhibited moderate cytotoxicity against human colon cancer HT29 cells, and it induced significant cell cycle arrest by reducing the protein expression of cyclin D1.
Small molecule inhibitors have dominated the pharmaceutical landscape for a long time as the primary therapeutic paradigm targeting pathogenic proteins. However, their efficacy heavily relies on the amino acid composition and spatial constitution of proteins, rendering them susceptible to drug resistance and failing to target undruggable proteins. In recent years, the advent of targeted protein degradation (TPD) technology has captured substantial attention from both industry and academia. Employing an event-driven mode, TPD offers a novel approach to eliminate pathogenic proteins by promoting their degradation, thus circumventing the limitations associated with traditional small molecule inhibitors. Hydrophobic tag tethering degrader (HyTTD) technology represents one such TPD approach that is currently in the burgeoning stage. HyTTDs employ endogenous protein degradation systems to induce the degradation of target proteins through the proteasome pathway, which displays significant potential for medical value. In this review, we provide a comprehensive overview of the development history and the reported mechanism of action of HyTTDs. Additionally, we delve into the physiological roles, structure-activity relationships, and medical implications of HyTTDs targeting various disease-associated proteins. Moreover, we propose insights into the challenges that necessitate resolution for the successful development of HyTTDs, with the ultimate goal of initiating a new age of clinical treatment leveraging the immense potential of HyTTDs.
New fabrication method of nanostructures is of great importance for the applications of nanoscience and nanotechnology. This review summarizes cucurbit[n]uril (CB[n])-based nanostructure fabrication and modification approaches. These strategies include the use of CB[n]s as building blocks and supramolecular crosslinkers to fabricate nanostructures, to surface modify nanostructures, and as gatekeepers to control the release of encapsulated cargo. These nanostructures are used for drug delivery, bioimaging, chemical sensing, catalysis and other applications. CB[n]s often play a vital role in the fabrication of these nanostructures, and the realization of the applications.
This work describes intermolecular acylfluorination of gem-difluoroenynes using acyl fluorides as both acyl source and fluorine source. Trifluoromethyl-substituted allenones or furans could be selectively achieved via phosphine and silver catalysis. These approaches exhibit high regioselectivity, atom economy and broad functionality tolerance.
Diradical polycyclic hydrocarbons (PHs) have unique open-shell structures and interesting physical properties. However, owing to high reactivity of unpaired electrons, such open-shell organic diradicaloids are usually less stable than closed-shell systems, limiting their practical applications. In this study, we report P=O-attaching of diradical PHs as a new strategy to enhance their stability while maintaining diradical properties. Three P=O-attached PHs containing the indeno[1,2-b]fluorene, fluoreno[3,2-b]fluorene and indeno[2,1-b]fluorene π-skeletons, respectively, were designed and synthesized. As theoretically and experimentally proved, two of them have the relatively large diradical characters and open-shell singlet diradical nature. In comparison to their all-carbon analogues, the attached electron-withdrawing P=O groups endow them with much lower LUMO/HOMO energy levels but preserved magnetic activities and physical properties, such as thermally accessible triplet species and multi-redox ability. Moreover, the P=O groups effectively decrease their oxidation activities and thereby lead to their remarkably excellent ambient stabilities. Thus, this P=O-attaching strategy will be applicable to other diradical PH systems and may promote the generation of stable organic diradicaloids for radical chemistry and materials.