Due to health hazards and co-contamination of mycotoxins, efficient separation and detection of multiple mycotoxins in food is highly desirable yet challenging. In this study, we prepared a novel mesoporous polypyrrole nanofiber mat (M-PPy NFM) for extracting multiple mycotoxins from food. The mesoporous effects and multifunctional PPy contribute to higher recovery and purification efficiency of M-PPy NFM for mycotoxins by facilitating hydrogen bonding and π-π interaction.
View Article and Find Full Text PDFObjective: This paper examines the impact of healthcare industry convergence on the performance of the public health system in the eastern, central, and western regions of China.
Methods: Public health performance was measured by a composite index of three standards: average life expectancy at birth, perinatal mortality, and maternal mortality. The healthcare industry convergence was measured using a coupling coordination degree method.
Background: G protein-coupled receptor kinases 6 (GRK6) is one kinase of GPCRs, previous studies have shown that GRK6 is involved in the regulation of inflammatory processes. However, the role of GRK6 in inflammation is not well understood and what is the effect of its palmitoylation modification on inflammatory response in macrophage are still largely unknown.
Methods: LPS stimulated Kupffer cells to simulate inflammatory injury model.
J Chromatogr B Analyt Technol Biomed Life Sci
March 2021
The demand for analysis of carotenoids (CAR) and fat-soluble vitamins (FSV) is continuously expanding, but currently used sample preparation methods either require complicated extraction procedure or large sample volume, let alone the reliability of the results. This study aimed to develop a fast, high-efficient, and high-throughput method based on supported liquid extraction (SLE) for the simultaneous extraction of FSV and CAR from human serum before using high-performance liquid chromatography-diode array detector (HPLC-DAD) analysis. The optimization of SLE parameters was achieved through response surface methodology (RSM) based on the Box-Behnken design (BBD) and included serum-water-extraction solvent ratio and eluent volume.
View Article and Find Full Text PDFObjective: Calcium-activated chloride channel 2 (CLCA2) is closely related to the invasion, metastasis, and prognosis of some common malignant tumors. The present study aimed to evaluate the role of CLCA2 in cervical squamous cell carcinoma (CESC) using bioinformatics analysis.
Materials And Methods: The mRNA sequencing data and the corresponding clinical data were obtained from Gene Expression Omnibus (GEO) database and The Cancer Genome Atlas (TCGA) database respectively.
CDK7 associates with the 10-subunit TFIIH complex and regulates transcription by phosphorylating the C-terminal domain (CTD) of RNA polymerase II (RNAPII). Few additional CDK7 substrates are known. Here, using the covalent inhibitor SY-351 and quantitative phosphoproteomics, we identified CDK7 kinase substrates in human cells.
View Article and Find Full Text PDFHelicobacter pylori is motile by means of polar flagella, and this motility has been shown to play a critical role in pathogenicity. The major structural flagellin proteins have been shown to be glycosylated with the nonulosonate sugar, pseudaminic acid (Pse). This glycan is unique to microorganisms, and the process of flagellin glycosylation is required for H.
View Article and Find Full Text PDFThe phenylacetate degradation pathway is present in a wide range of microbes. A key component of this pathway is the four-subunit phenylacetyl-coenzyme A monooxygenase complex (PA-CoA MO, PaaACBE) that catalyzes the insertion of an oxygen in the aromatic ring of PA. This multicomponent enzyme represents a new family of monooxygenases.
View Article and Find Full Text PDFThe ubiquitin-specific protease (USP) structural class represents the largest and most diverse family of deubiquitinating enzymes (DUBs). Many USPs assume important biological roles and emerge as potential targets for therapeutic intervention. A clear understanding of USP catalytic mechanism requires a functional evaluation of the proposed key active site residues.
View Article and Find Full Text PDFThe utilization of phenylacetic acid (PA) in Escherichia coli occurs through a hybrid pathway that shows features of both aerobic and anaerobic metabolism. Oxygenation of the aromatic ring is performed by a multisubunit phenylacetyl-coenzyme A oxygenase complex that shares remote homology of two subunits to well studied bacterial multicomponent monooxygenases and was postulated to form a new bacterial multicomponent monooxygenase subfamily. We expressed the subunits PaaA, B, C, D, and E of the PA-CoA oxygenase and showed that PaaABC, PaaAC, and PaaBC form stable subcomplexes that can be purified.
View Article and Find Full Text PDFRecombinant human brain calbindin D(28K) (rHCaBP), human Cu,Zn-superoxide dismutase (HCuZnSOD), rabbit muscle glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and bovine serum albumin (BSA) were found to be S-glutathiolated in decomposed S-nitrosoglutathione (GSNO) solutions. Tryptic or Glu-C digestion and MALDI-TOF MS analyses of the digests are consistent with S-thiolation of Cys111 and Cys187 of HCuZnSOD and rHCaBP, respectively, upon exposure to decomposed GSNO. GAPDH activity analysis reveals that S-glutathiolation most likely occurs on the active site Cys149, and the single free Cys34 is assumed to be the site of S-glutathiolation in BSA.
View Article and Find Full Text PDFMass spectrometry and UV-vis absorption results support a mechanism for NO donation by S-nitrosoglutathione (GSNO) to recombinant human brain calbindin D(28K) (rHCaBP) that requires the presence of trace copper, added as either Cu,Zn-superoxide dismutase (CuZnSOD) or CuSO(4). The extent of copper-catalyzed rHCaBP S-nitrosation depends on the ratio of protein to GSNO and on the reaction time, and NO-transfer is prevented when copper chelators are present. CuZnSOD is an efficient catalyst of rHCaBP S-nitrosation, and the mechanism of CuZnSOD-catalyzed S-nitrosation involves reduction of the active-site Cu(II) by a number of the five free thiols in rHCaBP, giving rise to thiyl radicals.
View Article and Find Full Text PDFCalbindin D(28K) is noted for its abundance and specific distribution in mammalian brain and sensory neurons. It can bind three to five Ca(2+) ions and may act as a Ca(2+) buffer to maintain intracellular Ca(2+) homeostasis, but its exact role is still unknown. In the present study, mass spectrometric analysis reveals that the five cysteine residues in recombinant human brain calbindin D(28K) (rHCaBP) are derivatized with N-ethylmaleimide, consistent with the determination of 5.
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