Publications by authors named "Weihua Ji"

The mass spectral library of the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) is the most comprehensive free reference database of its kind in the world. It provides reliable mass spectra for identification of seized drugs, their metabolites, and related forensic compounds when using gas chromatography/mass spectrometry (GC/MS). The SWGDRUG library (version 3.

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  • The study addresses the trade-off between activity and selectivity in acetylene semi-hydrogenation by developing a new Au@PdCu core-shell nanocatalyst that enhances both properties.
  • The nanocatalyst achieved 100% acetylene conversion and 92.4% ethylene selectivity at 122 °C, with performance 3.3 times better than a traditional PdCu alloy.
  • Advanced techniques like pair distribution function (PDF) and reverse Monte Carlo simulation (RMC) were used to analyze the atomic structure, revealing that low coordination and tensile strain in palladium sites are key for improving catalytic performance.
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  • The study focuses on how thermal expansion can be controlled at the molecular level, which is crucial for materials science applications.
  • A specific compound, Fe(pyz)Pt(CN), was identified to exhibit negative thermal expansion (NTE) in two dimensions and can be altered to positive thermal expansion (PTE) or zero thermal expansion (ZTE) by modifying its structure or adding iodine ions.
  • The research shows that the spin state of iron (Fe) influences the extent of NTE, with the high-spin state enhancing NTE compared to the low-spin state, revealing new insights for designing materials with tailored thermal properties.
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Background: Cardiovascular (CV) risk estimation calculators for the general population underperform in patients with rheumatoid arthritis (RA). The purpose of this study was to identify relevant protein biomarkers that could be added to traditional CV risk calculators to improve the capacity of coronary artery calcification (CAC) prediction in individuals with RA. In a second step, we quantify the improvement of this prediction of CAC when these circulating biomarkers are added to standard risk scores.

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Supported atomic dispersion metals are of great interest, and the interfacial effect between isolated metal atoms and supports is crucial in heterogeneous catalysis. Herein, the behavior of single-atom Cu catalysts dispersed on CeO (100), (110), and (111) surfaces has been studied by DFT + U calculations. The interactions between ceria crystal planes and isolated Cu atoms together with their corresponding catalytic activities for CO oxidation are investigated.

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Zero thermal expansion (ZTE) is an intriguing phenomenon by virtue of its peculiar lack of expansion and contraction with temperature. The achievement of ZTE in a metallic material is a desired but challenging task. Here we report the ZTE behavior of a single-phase metallic VB compound, stacking with the V and B atomic layers along the direction (α = 2.

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Medication overuse headache (MOH) has a high relapse rate and disease heterogeneity. This study aimed to determine the predictors of MOH relapse in patients through a 6-month follow-up in Shanghai. In this retrospective study, patients diagnosed with MOH from June 2016 to June 2017 were recruited and followed up for 6 months after withdrawal treatment in Renji Hospital in Shanghai.

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A method to discover and correct errors in mass spectral libraries is described. Comparing across a set of highly curated reference libraries compounds that have the same chemical structure quickly identifies entries that are outliers. In cases where three or more entries for the same compound are compared, the outlier as determined by visual inspection was almost always found to contain the error.

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Derivitization of peptides with isobaric tags such as iTRAQ and TMT is widely employed in proteomics due to their compatibility with multiplex quantitative measurements. We recently made publicly available a large peptide library derived from iTRAQ 4-plex labeled spectra. This resource has not been used for identifying peptides labeled with related tags with different masses, because values for virtually all masses of precursor and most product ions would differ for ions containing the different tags as well as containing different tag-specific peaks.

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Multiple reaction monitoring (MRM) is an increasingly popular mass spectrometry-based method to simultaneously detect and quantify multiple proteins. MRM is particularly useful for validating biomarkers discovered with a mass spectrometer and any analite discovered by MS can be monitored by MR because an MRM assay can be developed without the need to generate specific antibodies. In this chapter, we present a robust and systematic procedure to rapidly build a high-sensitivity MRM assay using purified protein as the starting material.

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Background: Human cardiac troponin I is known to be phosphorylated at multiple amino acid residues by several kinases. Advances in mass spectrometry allow sensitive detection of known and novel phosphorylation sites and measurement of the level of phosphorylation simultaneously at each site in myocardial samples.

Methods And Results: On the basis of in silico prediction and liquid chromatography/mass spectrometry data, 14 phosphorylation sites on cardiac troponin I, including 6 novel residues (S4, S5, Y25, T50, T180, S198), were assessed in explanted hearts from end-stage heart failure transplantation patients with ischemic heart disease or idiopathic dilated cardiomyopathy and compared with samples obtained from nonfailing donor hearts (n=10 per group).

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Background: The aim of the present study was to investigate the expression and activity of epithelial sodium channel (ENaC) in hyperoxia-induced bronchopulmonary dysplasia (BPD) in neonatal rats.

Methods: Neonatal rats were exposed to hyperoxia to establish BPD models (control group was exposed to air), lung water was measured and Western blot was applied to detect the expression of three homologous subunits: α-, β- and γ-ENaC in the lung tissues. Furthermore, ATII cells were isolated from neonatal rats, and primarily cultured under normoxic or hyperoxic conditions.

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Objective: Patients with metabolic syndrome (MetS) are at a high risk for developing atherosclerosis and cardiovascular disease. Serum levels of chemerin have been found elevated in subjects with MetS and are associated with several cardiovascular factors. This study was undertaken to determine whether serum chemerin levels are associated with coronary artery disease (CAD) in patients with MetS.

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A liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous determination of pioglitazone (PIO) and its two metabolites: M-III (keto-derivative) and M-IV (hydroxy-derivative) in human plasma. Human plasma samples of 0.2 ml were extracted by a single step liquid-liquid extraction procedure and analyzed using a high performance liquid chromatography (HPLC) electrospray tandem mass spectrometer system.

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A small library consisting of two series of thymidine derivatives containing o-carboranylalkyl groups at the N-3 position was prepared. In both series, alkyl spacers of 2-7 methylene units were placed between the o-carborane cage and the thymidine scaffold. In one series, an additional dihydroxypropyl substituent was introduced at the second carbon atom of the carborane cage.

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Boron neutron capture therapy (BNCT) is a chemoradio-therapeutic method for the treatment of cancer. It depends on the selective targeting of tumor cells by boron-containing compounds. One category of BNCT agents with potential to selectively target tumor cells may be thymidine derivatives substituted at the 3'-position with appropriate boron moieties.

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