Publications by authors named "Sheng-Jian Li"

Magnetic nanomaterials were functionalized with dopamine hydrochloride as the functional reagent to afford a core-shell-type FeO modified with polydopamine (FeO@PDA) composite, which was used for the adsorption of cadmium ions from an aqueous solution. In addition, the effects of environmental factors on the adsorption capacity were investigated. Furthermore, the adsorption kinetics, isotherm, and thermodynamics of the adsorbents were discussed.

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(Z) Enol triflates 6, 11b-d, (E) enol triflate 11e, and phenol triflate 11a, derived from β-keto esters or 2-carboalkoxy phenols, respectively, react with N-Boc 2-lithiopyrrolidine (5a), N-Boc N-methylaminomethyllithium (5b), or 2-lithio-1,3-dithiane (14) to afford 3(2H)-furanones in modest to good yields (38-81%). Product and carbanion reagent studies suggest that the 3(2H)-furanone is formed in a cascade of reactions involving nucleophilic acyl substitution, enolate formation, trifluoromethyl transfer, iminium or sulfenium ion formation, and subsequent ring closure to form the 3(2H)-furanone. The use of 2-lithio-1,3-dithiane affords a cyclic α-keto-S,S,O-orthoester in which the functionality can be selectively manipulated for synthetic applications.

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Objective: To investigate the efficacy of novel object recognition (NOR) test in assessment of learning and memory ability in ICR mice in different experimental conditions.

Methods: One hundred and thirty male ICR mice were randomly divided into 10 groups: 4 groups for different inter-trial intervals (ITI: 10 min, 90 min, 4 h, 24 h), 4 groups for different object materials (wood-wood, plastic-plastic, plastic-wood, wood-plastic) and 2 groups for repeated test (measured once a day or every 3 days, totally three times in each group). The locomotor tracks in the open field were recorded.

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Objective: To study of the role of nuclear transcription factor-κB (NF-κB) in high glucose-induced apoptosis in INS-1 cells.

Methods: Rat insulinoma (INS-1) cells cultured in RPMI 1640 medium were treated with 11.1 mmol/L glucose, 33.

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Objective: To observe the effect of glucagon-like peptide-1 (GLP-1) on interleukin-1β (IL-1β)-induced damage in INS-1 cells and explore its possible mechanisms.

Methods: INS-1 cells were divided into normal control group, IL-1β group, and GLP-1+IL-1β group with corresponding treatments. The cell viability was determined by MTT assay, the expression of IKKβ mRNA was detected by real-time PCR, and that of the protein p65 was detected by Western blotting.

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R-spondins (Rspos) potentiate Wnt/beta-catenin signaling, an important pathway in embryonic development that is constitutively active in many cancers. To analyze Rspo structure and function, we expressed full-length wild-type Rspo2 and Rspo2 point mutants corresponding to Rspo4 variants that have been linked to developmental defects. The Rspo2 mutants had markedly reduced potency relative to the wild-type protein,demonstrating for the first time specific amino acid residues in Rspos that are critical for beta-catenin signaling.

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Protein-disulfide isomerase (PDI), a critical enzyme responsible for oxidative protein folding in the eukaryotic endoplasmic reticulum, is composed of four thioredoxin domains a, b, b', a', and a linker x between b' and a'. Ero1-Lalpha, an oxidase for human PDI (hPDI), has been determined to have one molecular flavin adenine dinucleotide (FAD) as its prosthetic group. Oxygen consumption assays with purified recombinant Ero1-Lalpha revealed that it utilizes oxygen as a terminal electron acceptor producing one disulfide bond and one molecule of hydrogen peroxide per dioxygen molecule consumed.

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We presented for the first time a small angle x-ray scattering study of intact protein-disulfide isomerase (PDI) in solution. The restored model revealed that PDI is a short and roughly elliptical cylinder with a molecular mass of 69 kDa and dimensions of 105 x 65 x 40 A, and the four thioredoxin-fold domains in the order a-b-b'-a' are arranged in an annular fashion. Atomic force microscope imaging also supported the finding that PDI appears as an approximately flat elliptical cylinder.

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Both homo- and mixed lithium di-alpha-(heteroatom)alkylcuprates readily dimerize upon addition of halogens (e.g., I(2), Br(2)) or N-halosuccinimides to afford the coupled products in excellent yields.

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alpha-(N-Carbamoylalkyl)cuprates couple with enol triflates derived from carbocyclic and heterocyclic (i.e., piperidinones) beta-keto esters.

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