Publications by authors named "Xiao-jian Hu"

Article Synopsis
  • Antibiotics and β-receptor agonists are commonly used in medicine and animal farming, but their presence can negatively impact human health, especially in growing teenagers.
  • A study analyzed urine samples from 442 middle school students aged 11-15 to determine the levels of these drugs, revealing a high detection rate of 89.8% for at least one substance.
  • The most frequently detected drugs were doxycycline, oxytetracycline, and azithromycin, with tetracyclines and macrolides being the most prevalent antibiotic categories.
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  • A novel analytical method was developed that combines automatic solid-phase extraction and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to detect 16 antibiotics and 4 -agonists in human urine samples.
  • The urine samples underwent specific preparation steps including the addition of internal standards, buffers, and enzymes, followed by a thorough extraction process that utilized Oasis PRiME HLB 96-well plates for optimal recovery rates.
  • The method was fine-tuned by testing different chromatography columns and mobile phases, achieving the best results with the HSS T column and a specific gradient elution setup using a 30% methanol aqueous solution.
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  • - Monoaromatic hydrocarbons (MAHs) like benzene and toluene are significant urban pollutants, and their urinary metabolites are monitored in various countries to assess human exposure.
  • - A new analytical method using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed to detect seven MAH metabolites in urine, involving hydrolysis and solid-phase extraction processes.
  • - This method achieved high detection accuracy with linear ranges for the metabolites and specific limits for detection and quantification, confirming its reliability through spiking urine samples for verification.
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  • A new ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed to simultaneously detect 12 personal care products (PCPs) in human urine, focusing on paraben preservatives, benzophenone UV absorbers, and antibacterial agents.
  • The process included mixing urine samples with a buffer solution, followed by overnight enzymatic hydrolysis, and then using solid phase extraction and chromatographic separation for analysis.
  • The method showed high sensitivity with low detection limits (0.06-1.09 μg/L) and excellent linearity for most analytes, achieving correlation coefficients greater than 0.999.
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  • * China is a major producer and user of pesticides, yet there’s a lack of data on human exposure, indicating a need for better measurement methods.
  • * The study developed a sensitive method for quantifying various pesticide metabolites in human urine using advanced techniques like UPLC-MS/MS, achieving good separation and accuracy in just 16 minutes.
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Objective: The study aimed to analyze the applicability of the World Health Organization's exclusionary guidelines for Urinary creatinine (Ucr) in the general Chinese population, and to identify Ucr related factors.

Methods: We conduct a cross-sectional study using baseline data from 21,167 participants in the China National Human Biomonitoring Program. Mixed linear models and restricted cubic splines (RCS) were used to analyze the associations between explanatory variables and Ucr concentration.

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is one of the most endangered Magnoliaceae species in China. Seed biology information concerning its long-term conservation and utilization is insufficient. This study investigated dormancy status, germination requirements and storage behavior of .

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Lactonohydrolase ZHD can detoxify oestrogenic mycotoxin zearalenone and zearalenols through hydrolysis and decarboxylation. The detail mechanism, especially the role of Trp183, which interacts with substrate through p-π interaction and one hydrogen bond, is still unknown. The Trp183 mutants abolished activity to ZEN, α-ZOL and β-ZOL, except that W183F mutant retained about 40% activity against α-ZOL.

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The gut bacterial bile salt hydrolase (BSH) plays a critical role in host lipid metabolism and energy harvest. Therefore, BSH is a promising microbiome target to develop new therapies to regulate obesity in humans and novel non-antibiotic growth promoters for food animals. We previously reported the 1.

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Objective: We aimed to characterize a novel SGNH (Ser-Gly-Asn-His) family hydrolase from the annotated genome of marine bacteria with new features.

Results: A novel esterase Ali5 from Altererythrobacter ishigakiensis has been identified and classified into SGNH family. Ali5 presented a novel GNSL (Gly-Asn-Ser-Leu(X)) motif that differs from the classic GDSL (Gly-Asp-Ser-Leu(X)) motif of SGNH family.

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Objective: The mainstay of treatment for advanced bladder cancer (BC) is cisplatin (CDDP)-based systematic chemotherapy. However, acquired chemoresistance induced by as yet unidentified mechanisms is encountered frequently and often results in treatment failure and disease progression. The present study was designed to elucidate the expression and potential role of the gene associated with retinoid-interferon-induced mortality-19 (GRIM19) in the pathogenesis of CDDP resistance in BC.

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Back pain is a worldwide health problem, adding a tremendous burden to modern societies. However, little information on back health is available in China, even though a quarter of the world's population is Chinese. To enhance knowledge in this area, we designed and initiated the Hangzhou Lumbar Spine Study, which is a cross-sectional study of a general sample of mainland Chinese with focusing on disc degeneration, Modic changes, endplate lesions, and back pain.

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Zearalenone hydrolase (ZHD) is an α/β-hydrolase that detoxifies and degrades the lactone zearalenone (ZEN), a naturally occurring oestrogenic mycotoxin that contaminates crops. Several apoenzyme and enzyme-substrate complex structures have been reported in the resolution range 2.4-2.

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The study investigated the effects and underlying mechanisms of silent information regulation of transcription 1 (Sirt1) action on apoptosis in chondrocytes and degradation of the extracellular matrix. Cartilage tissue samples were derived from knee arthroplasty of patients with osteoarthritis (OA). The three groups were as follows: Control, resveratrol (Res) and Res+small interfering (si)RNA (Res+siRNA Sirt1).

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The emission spectrum of widely used CyPet is pH-sensitive. In order to synthesize a pH-insensitive cyan fluorescent protein by rational design, we solved the crystal structures of CyPet under different pH conditions. The indole group of the CyPet chromophore adopts a cis-coplanar conformation in acidic and neutral conditions, while it converts to trans-coplanar under basic conditions.

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The red fluorescent protein variant TagRFP-T has greatly improved photostability over its parent molecule, TagRFP, but the underlying mechanism leading to this improvement is to date unknown. The 1.95 Å resolution crystallographic structure of TagRFP-T showed that its chromophore exists as a mixture of cis and trans coplanar isomers in roughly equal proportions.

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Bile salt hydrolase (BSH) is a gut-bacterial enzyme that negatively influences host fat digestion and energy harvesting. The BSH enzyme activity functions as a gateway reaction in the small intestine by the deconjugation of glycine-conjugated or taurine-conjugated bile acids. Extensive gut-microbiota studies have suggested that BSH is a key mechanistic microbiome target for the development of novel non-antibiotic food additives to improve animal feed production and for the design of new measures to control obesity in humans.

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Human 3α-HSD3 (3α-hydroxysteroid dehydrogenase type 3) plays an essential role in the inactivation of the most potent androgen 5α-DHT (5α-dihydrotestosterone). The present study attempts to obtain the important structure of 3α-HSD3 in complex with 5α-DHT and to investigate the role of 3α-HSD3 in breast cancer cells. We report the crystal structure of human 3α-HSD3·NADP(+)·A-dione (5α-androstane-3,17-dione)/epi-ADT (epiandrosterone) complex, which was obtained by co-crystallization with 5α-DHT in the presence of NADP(+) Although 5α-DHT was introduced during the crystallization, oxidoreduction of 5α-DHT occurred.

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Human 3-alpha hydroxysteroid dehydrogenase type 3 (3α-HSD3) has an essential role in the inactivation of 5α-dihydrotestosterone (DHT). Notably, human 3α-HSD3 shares 97.8% sequence identity with human 20-alpha hydroxysteroid dehydrogenase (20α-HSD) and there is only one amino acid difference (residue 54) that is located in their steroid binding pockets.

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Background: Xiaochaihu Decoction (XCHD) prevents hepatocarcinogenesis in association with inhibition of oxidative stress. However, alkaline phosphatase (ALP) activity, lipopolysaccharides (LPS)-catecholamines (CA) interactions in gut, liver and brain may play an important role in the status of oxidative stress. This study was to assess whether XCHD attenuates the vicious circle between oxidative stress and ALP inactivation through LPS-CA interactions.

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A new psychrophilic marine protease was found from a marine bacterium Flavobacterium YS-80 in the Chinese Yellow Sea. The protease is about 49 kD with an isoelectric point about 4.5.

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Sau3AI is a type II restriction enzyme that recognizes the 5'-GATC-3' sequence in double-strand DNA and cleaves at 5' to the G residue. The C-terminal domain of Sau3AI (Sau3AI-C), which contains amino acids from 233 to 489, was crystallized and its structure was solved by using the Multi-wavelength Anomalous Diffraction method. The Sau3AI-C structure at 1.

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Cytochalasin B was used to inhibit the glucose transport through the glucose transport protein (GluT-1) in red cell membranes. It was observed that the anion transport was increased at the same time. The rate of anion transport was also increased when GluT-1 was bound with its substrate molecule-glucose.

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