Identification and quantification of bipyridyl dicarboxylic acid isomers by ion mobility spectrometry.

The identification of positional isomers is of interest because different isomers have different chemical or biological functions and applications. The analysis of positional isomers is sometimes challenging since they have similar chemical structures and properties. For example, the analysis of mass cannot identify different positional isomers because they have identical mass-to-charge ratios and show a single mass peak in mass spectrometry. In this study, an efficient and simple qualitative and quantitative analytical method for differentiating 2,2'-bipyridine-3,3'-dicarboxylic acid (3,3'-BDA), 2,2'-bipyridine-4,4'-dicarboxylic acid (4,4'-BDA), and 2,2'-bipyridine-5,5'-dicarboxylic acid (5,5'-BDA) was developed by using ion mobility spectrometry (IMS). The results revealed that the three BDA isomers formed non-covalent complexes with cyclodextrins (CDs) and Mg2+ ions in the gas phase: [ß-CD+3,3'/4,4'/5,5'-BDA+Mg]2+ and [γ-CD+3,3'/4,4'/5,5'-BDA+Mg]2+, which were distinguished by measuring the mobility of the complexes because of their spatial conformational differences. The peak-to-peak resolution (Rp-p) values of the three isomers of [γ-CD+3,3'/4,4'/5,5'-BDA+Mg]2+ reached 2.983 and 2.892, respectively. The conformations of the ternary complexes simulated by the theoretical calculations revealed the different interactions and shapes of the stereoisomers, and the predicted results agreed with the experimental results. Simultaneously, further studies on the collisional dissociation of the ternary complexes revealed that the dissociation energies of the different complex ions varied were different owing to the diverse different conformations. Finally, the relative quantitative analysis of the different isomers in mixed samples was performed and satisfactory linearity results (R2 > 0.99) were obtained. Thus, an effective analytical method was proposed for the identification and quantification of BDA isomers without chemical derivatization, offering a promising approach for the identification of similar derivatives or positional isomers that could be applied in various fields including chemicals and pharmaceuticals.

Self-assembled core-shell clusters in deep eutectic solvents based on tetra-n-alkylammonium cations for high dissolution of strongly hydrogen-bonded small molecules.

Strongly hydrogen-bonded compounds such as 1,3,5-triamino-2,4,6­trinitrobenzene (TATB, an important insensitive high explosive) have excellent stability, but poor solubilities to limit their recrystallization, purification and recycling. In this study, core-shell clusters based on symmetrical tetra-n-alkylammonium [TTA]+ are designed to provide an inner cavity to incorporate TATB, and thus the clusters can separate TATB from original hydrogen-bonded networks to increase largely the solubility. Based on this design, deep eutectic solvents (DESs) based on [TTA]+ cations are first developed to yield self-assembled core-shell clusters for solubilizing TATB. Ninety-nine DESs based on [TTA]+ were prepared by combining with halide ions and hydrogen bond donors, and TATB's solubility increases with the formation of core-shell clusters. Tetrabutyl ammonium ([TBA]+ )-based DES (CS-1) displays excellent dissolution toward TATB. Room-temperature solubility of TATB in CS-1 with 32.88 mg/mL is about 10 times higher than recently reported ionic liquids and approximately 470 times higher than DMSO. Compared to traditional solvents, CS-1 shows economical and high dissolution ability toward TATB. The dissolution mechanism is demonstrated by experimental characterizations and theoretical calculations. After forming Zundel-type complexes between TATB and F-, the complexes as the core are surrounded by [TBA]+ as the shell to yield core-shell clusters through self-assembly of electrostatic interaction.

Double-edged role of interlayer water on Li+ extraction from ultrahigh Mg2+/Li+ ratio brines using Li/Al-LDHs.

Lithium-aluminum layered double hydroxides (Li/Al-LDHs) are the only industrial adsorbents for Li+ extraction from Mg2+/Li+ ratio brines dependent on the special neutral desorption without dissolution damage. In this work, Li/Al-LDHs with different interlayer water contents were designed for the investigation of correlation between interlayer water and Li+ adsorption performances in high Mg2+/Li+ ratio brines. On the one hand, the Li+ adsorption capacity of Li/Al-LDHs in the Qarham Salt Lake old brine with a Mg2+/Li+ ratio exceeding 300 presented a positive correlative relation with the interlayer water content, rising from 1.05 mg/g to 7.89 mg/g as the interlayer water content increased from 5.52% to 18.18%. On the other hand, the interlayer water content would not affect the structure stability of Li/Al-LDHs, while the interlayer spacing was lessened with less interlayer water resulting in an uptrend to the adsorption selectivity on account of the depressed confinement effect. The density functional theory (DFT) calculation further indicated that LiCl was easier to enter the structure of Li/Al-LDHs with more interlayer water in view of the greater interaction energy.

Supramolecular-induced 2.40 V 130 °C working-temperature-range supercapacitor aqueous electrolyte of lithium bis(trifluoromethanesulfonyl) imide in dimethyl sulfoxide-water.

Increasing the electrochemical stability window and working temperature range of supercapacitor aqueous electrolyte is the major task in order to advance aqueous electrolyte-based supercapacitors. Here, a supramolecular induced new electrolyte of lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) in dimethyl sulfoxide (DMSO) and water co-solvent system is proposed. Adjusting the coordination structure among LiTFSI, DMSO, and water in the electrolyte via supramolecular interactions results in its high ionic conductivity, low viscosity, wide electrochemical stability window, and large working temperature range. The new electrolyte-based supercapacitors can work in 2.40 V working potential and 130 °C working-temperature range from -40 to 90 °C. The devices exhibit good electrochemical performances, especially the energy density over 21 Wh kg-1, which is much higher than that with traditional aqueous electrolytes (<10 Wh kg-1). The work paves a way to develop high-performance aqueous electrolytes for supercapacitors.

Mechanism and therapeutic prospect of resveratrol combined with TRAIL in the treatment of renal cell carcinoma.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been reported to kill a wide variety of tumor cells with minimal effects on normal cell. However, renal cell carcinoma (RCC) cells 786-0 and OS-RC-2 were resistant to TRAIL. The present study examines the potential of combining polyphenolic compound resveratrol (RES) with TRAIL. We found that RES can sensitize RCC cells to TRAIL-induced death. Electron microscopy analyses showed that RES plus TRAIL can induce both autophagy and apoptosis in RCC cells. It was proved that the apoptosis is caspase-dependent and the activation of caspase-8, caspase-9, and caspase-3 was involved in this process. Besides, we also found that XIAP expression was significantly inhibited after RES plus TRAIL treatment in RCC cells. Furthermore, a fiber-modified replication-deficient adenovirus Ad5/35-TRAIL was generated to test the synergistic effect of RES and TRAIL in vivo. Our data demonstrated that RES plus Ad5/35-TRAIL significantly inhibited RCC xenograft growth in nude mice. These results suggest the possibility of a new combination therapeutic leading to the improvement of RCC treatment.

RETRACTED: Function of the PLZF gene in early development and self-renewal of T cells in mice.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).. This article has been retracted at the request of < the Editor in Chief. The Editor in Chief has been made aware of numerous problems with this paper regarding authorship, poor or insufficient supervision of researchers and the unauthorized use of data acquired from a lab visit by one of the authors.

Induction and Suppression of Innate Antiviral Responses by Hepatitis A Virus.

Hepatitis A virus (HAV) belongs to the family Picornaviridae. It is the pathogen of acute viral hepatitis caused by fecal-oral transmission. RNA viruses are sensed by pathogen-associated pattern recognition receptors (PRRs) such as Toll-like receptor 3 (TLR3), retinoic acid-inducible gene I (RIG-I), and melanoma differentiation-associated gene 5 (MDA5). PRR activation leads to production of type 1 interferon (IFN-α/ß), serving as the first line of defense against viruses. However, HAV has developed various strategies to compromise the innate immune system and promote viral propagation within the host cells. The long coevolution of HAV in hosts has prompted the development of effective immune antagonism strategies that actively fight against host antiviral responses. Proteases encoded by HAV can cleave the mitochondrial antiviral signaling protein (MAVS, also known as IPS-1, VISA, or Cardif), TIR domain- containing adaptor inducing IFN-ß (TRIF, also known as TICAM-1) and nuclear factor-κB (NF-κB) essential modulator (NEMO), which are key adaptor proteins in RIG-I-like receptor (RLR), TLR3 and NF-κB signaling, respectively. In this mini-review, we summarize all the recent progress on the interaction between HAV and the host, especially focusing on how HAV abrogates the antiviral effects of the innate immune system.