Publications by authors named "Wei-Wei Yao"

Objective: To compare the ability of gadolinium ethoxybenzyl dimeglumine (Gd-EOB-DTPA) and gadobenate dimeglumine (Gd-BOPTA) to display the 3 major features recommended by the Liver Imaging Reporting and Data System (LI-RADS 2018v) for diagnosing hepatocellular carcinoma (HCC).

Materials And Methods: In this retrospective study, we included 98 HCC lesions that were scanned with either Gd-EOB-DTPA-MR or Gd-BOPTA-M.For each lesion, we collected multiple variables, including size and enhancement pattern in the arterial phase (AP), portal venous phase (PVP), transitional phase (TP), delayed phase (DP), and hepatobiliary phase (HBP).

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Objective: To compare the ability to depict MRI features of hepatobiliary agents in microvascular infiltration (MVI) of hepatocellular carcinoma (HCC) during different stages of dynamic enhancement MRI.

Materials And Methods: A retrospective study included 111 HCC lesions scanned with either Gd-EOB-DTPA or Gd-BOPTA. All cases underwent multiphase dynamic contrast-enhanced scanning before surgery, including arterial phase (AP), portal venous phase (PVP), transitional phase (TP), delayed phase (DP), and hepatobiliary phase (HBP).

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The effective and mild [4+1] annulation of ninhydrin-derived MBH carbonates with α,β-unsaturated ketones has been developed, providing a wide range of multisubstituted furans in high yields (up to 90%) with excellent β-regioselectivities. In contrast, the polysubstituted cyclopentenes bearing dispiro-bisindanedione motifs were obtained classical [3+2] annulations by employing ninhydrin-derived MBH carbonates with 2-arylidene-1,3-indandiones under the same catalytic conditions. Furthermore, the structures of two kinds of cycloadducts were straightforwardly confirmed through X-ray diffraction analysis.

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Allylic amines are versatile building blocks in organic synthesis and exist in bioactive compounds, but their synthesis via hydroaminoalkylation of alkynes with amines has been a formidable challenge. Here, we report a late transition metal Ni-catalyzed hydroaminoalkylation of alkynes with N-sulfonyl amines, providing a series of allylic amines in up to 94% yield. Double ligands of N-heterocyclic carbene (IPr) and tricyclohexylphosphine (PCy) effectively promote the reaction.

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Volatile organic compounds (VOCs) emitted by organisms and cell metabolism have demonstrated great physiological and pathological values. At present, there is a great interest in the study of volatile metabolome to determine whether VOCs can serve as potential diagnostic biomarkers. In view of the sensitivity of VOCs to physiological changes, the aim of this study was to investigate alterations in VOC profiles in the in vitro headspace of HepG2 cells after exposure to triclosan (TCS).

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To explore the permeation mechanism of micro-molecule medicinal ingredients of water extract of tradition Chinese medicine(TCM) in membrane separation process. With phenolic acid components as the model solute, five phenolic acids with similar molecular weight and structure, namely gallic acid, protocatechuate acid, 4-hydroxybenzoic acid, 3-hydroxybenzoic acid and salicylic acid, were selected in the PES membrane separation experiments. With the relative flux and the transmission rate as indexes, the scanning electron microscopy(SEM) and the electrochemical impedance spectroscopy(EIS) were used to analyze the permeation mechanism of different phenolic acid components.

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In order to analyze the law of membrane permeation of different alkaloids, seven traditional Chinese medicine alkaloids with different parent nucleus and substituent structures, including berberine, palmatine, sinomenine, matrine, oxymatrine, sophoridine, and tetrandrine, were prepared into the simulated solution with same molar concentration, and the membrane penetrating experiments with membrane RC1K and membrane RC5K were carried out. The dynamic transmittance, the total transmittance and the total adsorption rate of each substance were measured, and the scanning electron microscopy (SEM) images of the membrane surface before and after the membrane experiment were considered to predict and analyze the reason of differences in dynamic transmittance of different alkaloids. The results showed that there were significant differences in the dynamic transmittance of the chemical constituents of different alkaloids during penetrating the two membranes.

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Article Synopsis
  • This study explores the use of vapor permeation membrane technology to separate essential oils from an oil-water extract derived from Forsythia suspensa.
  • Two types of membrane materials, PDMS/PVDF composite and PVDF alone, were compared in terms of their efficiency in extracting essential oil.
  • The findings indicated that the PVDF membrane yielded significantly more essential oil and had a chemical composition that closely resembled traditional steam distillation methods, suggesting its superior suitability for this application.
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A Brønsted acid enabled nickel-catalyzed hydroalkenylation of aldehydes and styrene derivatives has been developed. The Brønsted acid acts as a proton shuttle to transfer a proton from the alkene to the aldehyde, thereby leading to an economical and byproduct-free coupling. A series of synthetically useful allylic alcohols were obtained through one-step reactions from readily available styrene derivatives and aliphatic aldehydes in up to 88 % yield and with high linear selectivity.

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In order to explore the adsorption characteristics of proteins on the membrane surface and the effect of protein solution environment on the permeation behavior of berberine, berberine and proteins were used as the research object to prepare simulated solution. Low field NMR, static adsorption experiment and membrane separation experiment were used to study the interaction between the proteins and ceramic membrane or between the proteins and berberine. The static adsorption capacity of proteins, membrane relative flux, rejection rate of proteins, transmittance rate of berberine and the adsorption rate of proteins and berberine were used as the evaluation index.

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Pd-catalyzed highly para-selective arylations of monosubstituted simple arenes with arylboronic acids to widely existed biaryls have been developed. Inspired by requisite amide-directing groups in reported selective oxidative couplings, amide ligands, especially DMF, are designed and found to be critical for the selectivity control in current arylations.

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An ortho-selective rhodium-catalyzed direct C-H arylation of 1,1'-bi-2-naphthol (BINOL), to deliver the widely used but not easily available 3,3'-diaryl BINOL, has been developed. This highly efficient one-step synthetic approach is the shortest route to date and is greatly facilitated by the newly developed ligand system comprising tBu PCl, Ph -cod, and Cy P⋅HBF . In addition, the same procedure can facilitate the challenging syntheses of 3-bulkyaryl BINOLs in good to excellent yields.

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A procedure was developed for initiating electron transfer from a gold electrode to a low molecular weight electron acceptor present inside supported lipid (lecithin) bilayers, followed by further electron transfer to an electron acceptor present in an aqueous solution. The electron acceptors present in the lecithin bilayers and aqueous phase were 7,7,8,8-tetracyanoquinodimethane (TCNQ) and [Fe(III)(CN)(6)](3-), respectively. A polished planar gold disk electrode was first coated via self-assembly procedures with an alkanethiol monolayer.

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Heterocyclic compounds with structures similar to vitamin E, but without the hydroxyl hydrogen atom, were synthesized and their electrochemical behavior examined in acetonitrile solutions and as solids in aqueous solutions of varying pH by attaching the compounds to the surface of a glassy carbon electrode. Compound 1, containing a fully methylated aromatic ring was found to be the most long-lived following one-electron oxidation, with its radical cation (1+*) surviving in acidic aqueous solutions and able to be isolated as a salt, 1+*(SbF6-), when reacted with NOSbF6 in CH3CN. Electrochemical, UV-vis and FTIR experiments on 1+*, in addition to the results from theoretical calculations, indicated that the electrochemical, electronic and structural properties of 1+* are very similar to those of the radical cation of vitamin E.

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Variable scan rate (0.1-500 V s(-1)) cyclic voltammetry experiments were performed on a series of model tocopherol (vitamin E) compounds with differing degrees of methyl substitution around the aromatic (phenolic) ring. alpha-Tocopherol, with a fully methylated aromatic ring, produced stable phenoxonium cations upon oxidation in CH3CN, and was modeled via an ECE mechanism (where "E" represents an electron transfer and "C" a chemical step).

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