Publications by authors named "Weijun Dai"

The use of light energy to drive photocatalytic organic transformations for the production of high-value-added organic compounds has garnered growing interest as a sustainable strategy for solving environmental problems and addressing the energy crisis. Naphthalenediimide (NDI) and perylenediimide (PDI)-based hybrid materials are highly regarded photocatalysts due to their strong visible-light absorption properties, highly electron-deficient aromatic cores, excellent redox activity, and tunable electrochemical and photochemical properties. However, although the design and preparation of NDI/PDI-based hybrid materials have progressed in the past few years, their application in photocatalytic organic reactions remains in the initial stage.

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The use of light energy to drive asymmetric organic transformations to produce high-value-added organic compounds is attracting increasing interest as a sustainable strategy for solving environmental problems and addressing the energy crisis. Chiral covalent organic frameworks (COFs), as porous crystalline chiral materials, have become an important platform on which to explore new chiral photocatalytic materials due to their precise tunability, chiral structure, and function. This review highlights recent research progress on chiral COFs and their crystalline composites, evaluating their application as catalysts in asymmetric photocatalytic organic transformations in terms of their structure.

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Background: Bacterial RNA polymerase (RNAP) is a promising target for antimicrobial chemotherapy due to its indispensable role in bacterial growth and survival. Among its components, only the rpoB gene encoding the β-subunit is known for its association with rifampicin resistance. We recently identified a variant of the RNAP α-subunit (RpoA) in Pseudomonas aeruginosa, conferring heightened bacterial susceptibility to antimicrobials.

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XRE-cupin family proteins containing an DNA-binding domain and a cupin signal-sensing domain are widely distributed in bacteria. In Pseudomonas aeruginosa, XRE-cupin transcription factors have long been recognized as regulators exclusively controlling cellular metabolism pathways. However, their potential functional roles beyond metabolism regulation remain unknown.

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The genetic diversities of subpopulations drive the evolution of pathogens and affect their ability to infect hosts and cause diseases. However, most studies to date have focused on the identification and characterization of adaptive mutations in single colonies, which do not accurately reflect the phenotypes of an entire population. Here, to identify the composition of variant subpopulations within a pathogen population, we developed a streamlined approach that combines high-throughput sequencing of the entire population cells with genotyping of single colonies.

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Inorganic-organic hybrid materials are a kind of multiduty materials with high crystallinity and definite structures, built from functional inorganic and organic components with highly tunable photochemical properties. Perylenediimides (PDIs) are a kind of strong visible light-absorbing organic dyes with π-electron-deficient planes and photochemical properties depending on their micro-environment, which provides a platform for designing tunable and efficient hybrid photocatalytic materials. Herein, four radical-doped PDI-based crystalline hybrid materials, Cl-PDI⋅SiWO (1), Cl-PDI⋅SiMoO (2), Cl-PDI⋅PWO (3), and Cl-PDI⋅PMoO (4), were attained by slow diffusion of polyoxometalates (POMs) into acidified Cl-PDI solutions.

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Nitrogen complexation with π-conjugated ligands is an effective strategy for synthesizing luminescent molecules. The asymmetric bridging ligands L (L1 and L2) have been designed. The terminal chelating sites of the L1 and L2 bridging ligands consisted of 2,2'-bipyridine (bpy) and 1,10-phenanthroline moieties (where L = L1 and L2; L1 = 2-(3-((4-([2,2'-bipyridin]-6-yl)benzyl)oxy)phenyl)-1-imidazo[4,5-][1,10]phenanthroline and L2 = 2-(3-((4-(6-phenyl-[2,2'-bipyridin]-4-yl)benzyl)oxy)phenyl)-1-imidazo[4,5-][1,10]phenanthroline).

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Quorum-sensing (QS) coordinates the expression of virulence factors in Pseudomonas aeruginosa, an opportunistic pathogen known for causing severe infections in immunocompromised patients. QS has a master regulator, the lasR gene, but in clinical settings, P. aeruginosa isolates have been found that are QS-active but LasR-null.

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Background: RNA polymerase (RNAP) is highly conserved and essential for prokaryotic housekeeping activities, making it an important target for the development of new antibiotics. The rpoB gene, encoding a β-subunit of bacterial RNAP, has a well-known association with rifampicin resistance. However, the roles of other RNAP component genes such as rpoA, encoding an α-subunit of RNAP, in antibiotic resistance remain unexplored.

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Novel monometallic (μ-LL')Ru, Ru(μ-LL'), homobimetallic Ru(μ-LL')Ru, and heterodimetallic Ru(μ-LL')Os and Os(μ-LL')Ru complexes based on two asymmetrical ligands LL' (where LL' = LL, LL) have been synthesized and characterized. Spectroscopic analysis indicates that all complexes exhibit intense spin-allowed ligand-centered (LC) transitions at 288 nm and Ru-based moderate spin-allowed MLCT absorption between 440-450 nm. The Ru(μ-LL')Os and Os(μ-LL')Ru dinuclear complexes show Os-based unit absorption in the range of 565-583 nm.

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We develop a biotin-based tandem labeling approach to improve detection sensitivity of DNA probe. Through DNA polymerase-mediated overhand filling, the 3'end of DNA probe was tandemly labeled with biotin molecules. The intensity of biotin signals could be flexibly manipulated by controlling the introduced length of poly(A) in the 5' overhang.

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Pseudomonas aeruginosa strain PAO1 has been commonly used in the laboratory, with frequent genome variations reported. Quorum sensing (QS), a cell-cell communication system, plays important role in controlling a variety of virulence factors. However, the evolution and adaptability of QS in those laboratory strains are still poorly understood.

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Exopolysaccharides (EPS) play critical roles in rhizobium-plant interactions. However, the EPS biosynthesis pathway in USDA110 remains elusive. Here we used transposon (Tn) mutagenesis with the aim to identify genetic elements required for EPS biosynthesis in USDA110.

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Essential genes are crucial for bacterial viability and represent attractive targets for novel anti-pathogen drug discovery. However, essential genes determined by the transposon insertion sequencing (Tn-seq) approach often contain many false positives. We hypothesized that some of those false positives are genes that are actually deleted from the genome, so they do not present any transposon insertion in the course of Tn-seq analysis.

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Quorum sensing (QS) is a microbial cell-cell communication mechanism and plays an important role in bacterial infections. QS-mediated bacterial infections can be blocked through quorum quenching (QQ), which hampers signal accumulation, recognition, and communication. The pathogenicity of numerous bacteria, including pv.

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Growing evidence has suggested that abnormally expressed long non-coding RNAs (lncRNAs) play critical regulatory roles in nasopharyngeal carcinoma (NPC) pathogenesis. Family with sequence similarity 225 member B (FAM225B) is a novel lncRNA that has been implicated in several human cancers, yet its role in the context of NPC remains largely unclear. The aim of this study was to determine the expression level of FAM225B and its clinical significance in NPC patients.

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Bradyrhizobium diazoefficiens USDA110 is one of the most effective nitrogen-fixing symbionts of soybeans. Here we carried out a large-scale transposon insertion sequencing (Tn-seq) analysis of strain Bd110spc4, which is derived from USDA110, with the goal of increasing available resources for identifying genes crucial for the survival of this plant symbiont under diverse conditions. We prepared two transposon (Tn) insertion libraries of Bd110spc4 with 155,042 unique Tn insertions when the libraries were combined, which is an average of one insertion every 58.

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Sirtuin 2 (SIRT2) is one of seven mammalian homologs of silent information regulator 2 (Sir2) and an NAD -dependent deacetylase; however, its critical role in lymphangiogenesis remains to be explored. We investigate SIRT2 mediated regulation of vascular endothelial growth factor D (VEGFD) expression and lymphangiogenesis by deacetylating endothelial PAS domain protein 1 (EPAS1) in head and neck cancer (HNC) in vitro and in vivo. In this study, we report that SIRT2, rather than other members of the Sir2 family, reduces the expression of VEGFD and lymphangiogenesis in hypoxia-induced HNC cells and transplanted HNC mice models by reducing EPAS1 acetylation at Lys674 and decreasing the transcriptional activity of EPAS1 target genes.

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Many Gram-negative bacteria communicate by using homoserine lactones (HSLs) as quorum sensing (QS) signals in a cell density-dependent manner. In addition to fatty acyl-HSL (acyl-HSL) signals, certain strains, most of them associated with plants, produce non-canonical aryl-HSLs such as cinnamoyl-HSL. However, the role of aryl-HSL in endophytic associations remained elusive.

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The revised Provisions for Drug Registration was promulgated by the State Administration for Market Regulation of China in March 2020 and came into force on July 1, 2020. This article describes the history of the drug registration management system in China, explains the background of the revision of the Provisions for Drug Registration in 2020, and introduces the main modifications of the Provisions for Drug Registration in 2020 in the aspects of registration classification, application for clinical trial on drug, application for drug marketing authorization, accelerated procedure for drug registration, working timeline, and supervision and administration. This article is intended to give a brief overview for those who wish to submit a drug registration application in China or for those who would like to get more acquainted with drug registration in China.

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Pseudomonas aeruginosa is an opportunistic pathogen with high clinical relevance for hospital infections of patients. Accumulating DNA sequencing results of clinical P. aeruginosa isolates have revealed frequent mutations in lasR gene, which encodes the highest arches component of quorum-sensing system (QS).

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The rice blast fungus Magnaporthe oryzae poses a great threat to global food security. During its conidiation (asexual spore formation) and appressorium (infecting structure) formation, autophagy is induced, serving glycogen breakdown or programmed cell death function, both essential for pathogenicity. Recently, we identified an M.

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Postoperative pain has well defined and is perceived by patients as one of the most obnoxious aspects of surgical pain. The aim of this study was to determine whether the combination of Therapeutic ultrasound (TUS) and Curcumin (CUR) resulted in an enhancement of their pain relieving activities in a rat model of postoperative pain. We explored the effect of these treatment and their interaction with signal transduction pathways involved in inflammatory.

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Background: Nasopharyngeal carcinoma (NPC) is the most common type of head and neck cancers which is notable for its distinctive pattern of geographical distribution. HOTAIR has been reported to regulate nasopharyngeal carcinoma tumorigenesis and progression. However, the detailed mechanism underlying HOTAIR-promoted nasopharyngeal carcinoma remains not fully understood.

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Studies have demonstrated that curcumin (CUR) exerts its tumor suppressor function in a variety of human cancers including head and neck squamous cell carcinoma (HNSCC). However, the exact underlying molecular mechanisms remain obscure. Here, we aim to test whether CUR affects ATM/Chk2/p53 signaling pathway, leading to the induction of cell cycle arrest, inhibition of angiogenesis of HNSCC and .

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