Publications by authors named "Yu-Xin Gu"

7 Publications

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Phase Ⅰ and phase Ⅱ metabolic studies of Citrus flavonoids based on electrochemical simulation and in vitro methods by EC-Q-TOF/MS and HPLC-Q-TOF/MS.

Food Chem 2022 Jun 22;380:132202. Epub 2022 Jan 22.

Department of Traditional Chinese Medicine, Hangzhou Red Cross Hospital, Hangzhou 310003, PR China. Electronic address:

The oxidation products and metabolic pathways of five Citrus flavonoids were studied by online electrochemical/quadrupole time-of-flight mass spectrometry (EC/Q-TOF/MS). The simulated oxidation metabolism of target compounds in phase I and phase Ⅱ was carried out at boron-doped diamond (BDD) working electrode. The results obtained by EC-MS were compared with the conventional metabolism of rats and humans reported in previous literatures. In addition, the method of incubating the target compounds with rat liver microsomes in vitro was established, the target compounds and their metabolites were analyzed by high performance liquid chromatography coupled mass spectrometry. The structures of the metabolites were determined by accurate mass measurements and previous in vivo metabolite results. The results showed that the electrochemical oxidation metabolites were consistent with the results of in vitro incubation of liver microsomes, and also with the results reported in other literatures. As a consequence, EC/Q-TOF/MS is a promising and effective tool for studying metabolic transformation of different complex food components.
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http://dx.doi.org/10.1016/j.foodchem.2022.132202DOI Listing
June 2022

Ion pair-based mobile phase additives to improve the separation of alkaloids in supercritical fluid chromatography.

J Pharm Biomed Anal 2022 Jan 9;208:114467. Epub 2021 Nov 9.

College of Pharmacy, Hangzhou Normal University, Hangzhou 311121, PR China; College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 311121, PR China. Electronic address:

In this study, a supercritical fluid chromatography (SFC) method based on ion pair reagents was used to separate alkaloids. The chromatographic parameters, including the stationary phase, additive type, additive concentration, outlet pressure, temperature and flow rate, were optimized. Baseline separation was completed in 20 min on an Agilent Pursuit 5 PFP column (4.6 × 150 mm) using carbon dioxide as the mobile phase and 7.5 mM sodium 1-pentanesulfonate as an additive with gradient elution at 140 bar, 60 °C, and a flow rate of 1.5 mL/min. The retention rate and resolution of the analytes were satisfactory. The limits of detection were 27.04-298.03 ng/mL, and the limits of quantification were 90.15-993.42 ng/mL. The recoveries of low and high concentrations were 77.46-111.86% and 83.84-111.00%, respectively. This ion pair additive greatly improved the separation efficiency of alkaloids. Consequently, this SFC method was successfully applied to the separation of alkaloids from Rhizoma corydalis.
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http://dx.doi.org/10.1016/j.jpba.2021.114467DOI Listing
January 2022

Boron nitride nanosheet-assisted matrix solid-phase dispersion microextraction of alkaloids from lotus plumule by high-performance liquid chromatography coupled with ultraviolet detection and ion mobility quadrupole time-of-flight mass spectrometry.

Electrophoresis 2022 02 21;43(4):581-589. Epub 2021 Nov 21.

College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, P. R. China.

A boron nitride nanosheet (BNNS)-assisted matrix solid-phase dispersion method was established to microextract alkaloids from medicinal plants. The target compounds were identified by high-performance liquid chromatography coupled with ultraviolet detection and ion mobility quadrupole time-of-flight mass spectrometry. During the experimental process, several important parameters, including the type of dispersant, the amount of dispersant, the grinding time, and the type of elution solvent, were optimized. Finally, the BNNSs were chosen as the best dispersant, and their microcosmic morphologies were identified by scanning electron microscopy and transmission electron microscopy. Because of the special property of BNNSs, the cost of this experiment was greatly reduced, especially in elution volume, sample amount (50 mg), and extraction time (2 min). Under the best conditions, 50 mg of sample powder was dispersed with 50 mg of BNNSs, the grinding time was 120 s, the mixed powder was eluted with 200 μL of methanol, and good linearity (r  > 0.9993) and satisfactory recoveries (80-100%) were obtained. The inter- and intraday precisions were acceptable, with RSDs lower than 2.01 and 4.84%, respectively. The limits of detection ranged from 2.54 to 15.00 ng/mL, and the limits of quantitation were 8.47 to 50.00 ng/mL. The proposed method was successfully applied for the determination of liensinine, isoliensinine, and neferine in lotus plumule.
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http://dx.doi.org/10.1002/elps.202100286DOI Listing
February 2022

Carbonized biosorbent assisted matrix solid-phase dispersion microextraction for active compounds from functional food.

Food Chem 2021 Dec 6;365:130545. Epub 2021 Jul 6.

College of Pharmacy, School of Medicine, Hangzhou Normal University, Hangzhou 311121, PR China; College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 311121, PR China. Electronic address:

In this study, mangosteen peel based activated carbon was prepared and first applied as adsorbent in matrix solid-phase dispersion (MSPD) for simultaneously extraction of flavonoids from Dendrobium huoshanense prior to their separation and determination by ultra-high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UHPLC-Q-TOF/MS). The MSPD-UHPLC-Q-TOF/MS method was validated exhaustively. Good linearities (r ≥ 0.9929) were obtained for all target analytes. The limits of detection was in the range of 0.00387-0.159 μg/g. Satisfactory recoveries of six target compounds were between 80.02 and 99.49% and 85.32-99.86% for the low and high spiked level, respectively. Furthermore, relative to other common sorbent, the prepared mangosteen peel based activated carbon was less expensive and more environmentally-friendly. Consequently, the proposed method was a simple, efficient, low-cost, eco-friendly, time-saving and sensitive approach that could be successfully applied to the extraction and determination of flavonoids compounds in complex matrix.
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http://dx.doi.org/10.1016/j.foodchem.2021.130545DOI Listing
December 2021

New insights into mechanism of bisphenol analogue neurotoxicity: implications of inhibition of O-GlcNAcase activity in PC12 cells.

Arch Toxicol 2019 09 22;93(9):2661-2671. Epub 2019 Jul 22.

State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.

Bisphenol analogues including bisphenol A and its derivatives are ubiquitous environmental contaminants and have been linked to adverse neurodevelopment effects on animals and humans. Most toxicological research focused on estrogen receptor mediated pathways and did not comprehensively clarify the observed toxicity. O-GlcNAcase (OGA), the highest level in brain, plays a critical role in controlling neuronal functions at multi-levels from molecule to animal behaviors. In this work, we intend to investigate the underlying molecular mechanisms for the neurotoxicity of bisphenol analogues by identifying their cellular targets and the resultant effects. The inhibitory actions of seven bisphenol analogues on the OGA activity at molecular level were investigated by our developed electrochemical biosensor. We found that their potency varied with substituent groups, in which tetrabromo bisphenol A (TBBPA) was the strongest. The seven bisphenol analogues (0-100 μM exposure) significantly inhibited OGA activity and up-regulated protein O-GlcNAcylation level in PC12 cells. Inhibition of OGA by bisphenol analogues further induced intracellular calcium, ROS, inflammation, repressed proliferation, interfered with cell cycle, induced apoptosis. And especially, 10 μM tetrabromo bisphenol A (TBBPA) exposure could impair the growth and development of neurite in human neural stem cells (hNSCs). Molecular docking for OGA/bisphenol analogue complexes revealed the hydrophobicity-dominated inhibition potency. OGA, as a new cellular target of bisphenol analogues, would illuminate the molecular mechanism of bisphenol analogues neurotoxicity.
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http://dx.doi.org/10.1007/s00204-019-02525-3DOI Listing
September 2019

Nuclear to cytoplasmic shift of p33(ING1b) protein from normal oral mucosa to oral squamous cell carcinoma in relation to clinicopathological variables.

J Cancer Res Clin Oncol 2008 Mar 6;134(3):421-6. Epub 2007 Sep 6.

Department of Stomatology, The First Hospital of Hebei Medical University, Shijiazhuang 050031, Hebei Province, China.

Purpose: p33(ING1b), as a candidate tumour suppressor gene, has been found to be expressed a proportion of oral squamous cell carcinomas (OSCCs), however, its clinicopathological significance is not studied yet. Our aim was to investigate association of p33(ING1b) expression with clinicopathological variables and particularly interesting new cysteine-histidine rich protein (PINCH) in OSCCs.

Methods: p33(ING1b) expression was immunohistochemically examined in 20 normal oral mucosa specimens and 49 OSCCs.

Results: Normal squamous cells showed only p33(ING1b )nuclear expression (no cytoplasmic expression), with a rate of 90% positive cases. While 24% of OSCCs appeared cytoplasmic expression (11 of them with weak nuclear staining) and the rest tumours (76%) were negative for p33(ING1b). Furthermore, the cases having lymph node metastasis showed a higher frequency of positive cytoplasmic expression than those without metastasis (P = 0.03). The p33(ING1b) cytoplasmic expression was positively related to PINCH expression (P = 0.04), the cases positive for both proteins had a high rate of the metastasis (P = 0.03).

Conclusions: The transfer of p33(ING1b) protein from the nucleus to the cytoplasm may result in loss of normal cellular function of the protein, which might play a role in the tumourigenesis and metastasis of OSCCs.
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http://dx.doi.org/10.1007/s00432-007-0305-yDOI Listing
March 2008

[Effect of periodontitis on circulating C-reactive protein in type 2 diabetes patients].

Hua Xi Kou Qiang Yi Xue Za Zhi 2006 Oct;24(5):435-7

Dept. of Stomatology, The First Hospital of Hebei Medical University, Shijiazhuang 050031, China.

Objective: To investigate the effect of periodontal infection on circulating C-reactive protein (CRP) in type 2 diabetes patients.

Methods: 32 diabetes patients with advanced periodontitis participated in this study. They were compared to a group of 32 diabetes patients without periodontal disease, who were mathed with regard to age (+/- 3 years), gender and body mass index (+/- 1 kg/m2). The concentration of CRP on circulation was measured by ELISA.

Results: Significant difference was found in the level of CRP and the percentage of subjects with elevated CRP levels > or = 3 mg/L on circulation between the two groups(P < 0.05).

Conclusion: Periodontal infection results in higher circulating CRP in type 2 diabetes patients. This elevated inflammatory factor may exacerbate insulin resistance and increase the risk for great vessels complications of diabetes mellitus.
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October 2006
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