Latest ArticlesValeriaquinone A (1), an unprecedented anthraquinone-coumarin hybrid, was isolated from the roots of Knoxia valerianoides. Its structure was determined by extensive spectroscopic analyses and X-ray diffraction. The plausible biosynthetic pathways for 1 were proposed. Compound 1 exhibited strong protein tyrosine phosphatase 1B (PTP1B) inhibition with high selectivity (> 30 fold) over homologous T cell protein tyrosine phosphatase (TCPTP) potentially by binding to an allosteric site predicted by kinetic analysis and molecular docking. Moreover, compound 1 showed significant cytotoxic activities against three human hepatoma cell lines (HepG2, QGY-7703, and SMMC-7721) with half maximal inhibitory concentration (IC50) values of 1.39 ± 0.2, 10.34 ± 2.09, and 5.56 ± 0.47 µmol/L, respectively.
Aromatic carboxylic acids (ACAs) may be as transformed key metabolites via gut microbiome for playing better pharmacological effects. However, it's rare to achieve high-specificity, high-sensitivity, and high-throughput detection simultaneously, especially, for tracing trace ACAs in gut microbiome. In this work, firstly, a novel dual-template and double-shelled molecularly imprinted 96-well microplates (DDMIPs) was designed and amplified signal for p-hydroxybenzoic acid (PBA) and 3, 4, 5-trimethoxycinnamic acid (TMA). Additionally, the DDMIPs and a stable isotope labeling derivatization (SILD) method combined with the ultra-high performance liquid chromatography triple quadrupole tandem mass spectrometry (UHPLC-TQ MS) was firstly stepwise integrated, achieving high-effective, high-sensitive, and high-throughput study of gut microbiome metabolism. The whole strategy showed lower limits of detections (LODs) up to 1000 folds than the traditional method, and revealed a more real metabolism-time profile of PBA and TMA by 3-step signal amplification. The platform also laid the foundation for fast, simple, high-selective, high-effective, and high-throughput metabolism and pharmacological research.
As human stem cells with the special pluripotency play important roles in the innovative drug discovery and regenerative medicine, development of extracellular matrix (ECM) mimetics or functional materials that can support stem cell growth and propagation is of high significance. Despite numerous efforts spent, one major limitation restricting the wide applications of stem cells to the clinical translation is the lack of efficient strategies for low cost and large-scale stem cell production under xeno-free culture conditions. Herein, we reported a new strategy with peptides-modified polystyrene-based polymers coated onto the surface of coverslips for the growth and reproduction of human embryonic stem cells (hESCs). The modified peptides are the active parts of proteins which has been shown to contribute to the pluripotent stem cell attachment or proliferation. The peptides were linked to the glass coverslips coated by the polymer materials via chemical crosslinking, and the composite substrates successfully maintain the long-term growth of HUES-7, H7 and DF699. Our study shows that the coating of polystyrene-derived polymer modified by our developed peptides is a good matrix for long-term growth and reproduction of stem cells. This polystyrene-derived polymer substrate can be produced in large scale and stored for a long time. The most important thing is that it can support the growth of undifferentiated human pluripotent stem cells (hPSCs) for more than ten passages, which could provide a new and relatively easy way to amplify hESCs in vitro.
Extracellular vesicles (EVs) are membrane vesicles secreted by cells, playing critical roles in mediating intercellular communications for various physiological and pathological processes. Most of the EV analysis is currently performed at the bulk level, obscuring the origin of the EVs and diverse characteristics of the individual extracellular vesicle. Technologies to analyze the extracellular vesicles at the single-cell and single-vesicle levels are needed to evaluate EV comprehensively and decode the heterogeneity underlying EV secretion. Microfluidic platforms that could control and manipulate fluids at the microscale provide an efficient way to achieve the aims. Various microfluidics-based technologies are emerging to realize single-cell EV secretion analysis and single EV analysis, which would be summarized in this mini-review.
Compared with traditional photodynamic therapy (PDT), ultrasound (US) triggered sonodynamic therapy (SDT) has a wide application prospect in tumor therapy because of its deeper penetration depth. Herein, a novel MnSiO3-Pt (MP) nanocomposite composed of MnSiO3 nanosphere and noble metallic Pt was successfully constructed. After modification with bovine serum albumin (BSA) and chlorine e6 (Ce6), the multifunctional nanoplatform MnSiO3-Pt@BSA-Ce6 (MPBC) realized the magnetic resonance imaging (MRI)-guided synergetic SDT/chemodynamic therapy (CDT). In this nanoplatform, sonosensitizer Ce6 can generate singlet oxygen (1O2) to kill cancer cells under US irradiation. Meanwhile, the loaded Pt has the ability to catalyze the decomposition of overexpressed hydrogen peroxide (H2O2) in tumor microenvironment (TME) to produce oxygen (O2), which can conquer tumor hypoxia and promote the SDT-induced 1O2 production. In addition, MP can degrade in mildly acidic and reductive TME, causing the release of Mn2+. The released Mn2+ not only can be used for MRI, but also can generate hydroxyl radical (∙OH) for CDT by Fenton-like reaction. The multifunctional nanoplatform MPBC has high biological safety and good anticancer effect, which displays the great latent capacity in biological application.
Cystic echinococcosis (CE) is one of the most harmful and life-threatening helminths. As the essential therapeutics, chemotherapy is always difficult to achieve desired anti-echinococcal effect due to the problems that the echinococcus granulosus cyst laminated layer makes the drug difficult to infiltrate and the poor solubility of drugs. In this study, we established a "breaking-then-curing" anti-echinococcal treatment strategy for efficient CE therapy. The photodynamic therapy (PDT) was used as a breaker to produce toxic reactive oxygen species (ROS) and damage the laminated layer of protoscolices (PSCs), leading to enhanced infiltration of albendazole sulfoxide nanoparticles (ABZSO NPs). Then, ABZSO NP was worked as curer for efficient anti-echinococcal treatment. As a result, the breaking-then-curing treatment strategy could generate more intracellular ROS in PSCs induced by plenty of ABZSO NPs, greatly increasing the mortality rate of PSCs in a shorter time than using ABZSO NPs alone, leading to the attenuation of laminated layer and finally disintegrating PSCs. We believe the "breaking-then-curing" strategy will suggest great potential in the treatment of CE and provide a new sight for anti-echinococcal treatment.
Coordination polymers (CPs) have great potential to be used in electrocatalysis owing to their designable compositions and structures. It is highly challenging to apply CPs as electrocatalysts for oxygen evolution reaction (OER) on account of insufficient catalytic efficiency and relatively poor stability of current electrocatalysts. Herein, through a mixed-metal strategy, one-dimensional CoNi1--HIPA with dual active sites was synthesized and studied for OER electrocatalysts. By changing the metal ratio of CoNi1--HIPA, the OER performance was well regulated. The optimized Co1/2Ni1/2-HIPA exhibited minimum reaction activation energy, and represented an overpotential of 367 mV to reach 10 mA/cm2 at 25 ℃. Moreover, an overpotential of 314 mV at 10 mA/cm2 was obtained from Co1/2Ni1/2-HIPA at 55 ℃. This mixed-metal strategy provides a feasible way for adjusting the electronic states of the electrocatalysts to improve the electrocatalytic OER performance.
Due to the frequent occurrence of oil spills and the large-scale production of oily wastewater, the treatment of oily sewage has become an important issue for sustainable development. Recently, materials prepared from lignocellulosic biomass (LCB) for oil-water separation have been found to be effective due to their high separation efficiency, good recyclability, and superior sustainability. However, few reviews have focused on the advantages and limitations of LCB for sewage treatment. This review summarizes the performance of modified LCB in oily wastewater treatment, in terms of the advanced modification methods applied and the structural dimensions of LCB materials according to the principle of superwetting oil-water separation. Research on the preparation technologies, separation mechanisms, and treatment efficiency of different LCB materials are briefly summarized, along with the characteristics of different LCB material types for oily wastewater treatment. Finally, the future prospects and challenges faced in the development of LCB materials are discussed.
The works on the procedure of fluorescent sensors for the detection of biological analytes are extremely momentous. Among diverse analytical approaches, fluorescence is the most eye-catching due to its high sensitivity, selectivity, rapidity, robustness, ease of measurement and non-destructive approaches. Herein, we show different fluorescent probes synthesized for estimation and detection of biological analytes (H2S, SO32−/HSO3−, H2O2, HOCl, HNO, ONOO−). These probes were constructed by masking the functional groups (hydroxyl and amino) of fluorophore and formation of active C=C, C=N, C=O and N=N for specific analytes. In this review we concentrate on synthesis of the probe, their photophysical properties and applications to biological studies.
MeOTf-catalyzed formal [4 + 2] annulation of styrene oxides with alkynes to afford polysubstituted naphthalenes has been realized, which undergoes sequential electrophilic cyclization/ring expansion. A range of substrates were tolerated in the formation of naphthalene derivatives with high regioselectivity in satisfactory yields. The reaction could also be carried out on gram scale.