Publications by authors named "Jian-wei Ren"

The new direct oral anticoagulants (DOACs) are increasingly used to treat and prevent thromboembolic disorders, and monitoring concentrations may be valuable in some special scenarios to prevent clinical adverse events. This study aimed to develop generic methods for the rapid and simultaneous analysis of four DOACs in human plasma and urine. Protein precipitation and one-step dilution were used to prepare the plasma and urine; the extracts were injected to ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for analysis.

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Objective: To establish a high-performance liquid chromatography orbital trap mass spectrometry (HPLC-Obitrap MS) method for screening 34 common drugs and metabolites in biological samples.

Methods: The target analytes in urine and blood samples were extracted with ethyl acetate, concentrated by nitrogen blowing and redissolved. The hair samples were washed with water and acetone, dried and cut into bits of about 1 mm, and then crushed in a freezing grinder.

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The unfolded protein response (UPR) plays an important role in carcinogenesis, but the functional role and mechanism of UPR-associated bladder carcinogenesis remain to be characterized. Upon UPR activation, ATF6α is activated to upregulate the transcription of UPR target genes. Although the mechanism of ATF6 activation has been studied extensively, the negative regulation of ATF6 stabilization is not well understood.

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Objective: To establish the method based on high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) with solid phase extraction (SPE) for simultaneous determination of the biological metabolites of aromatic compounds, including N-acetyl-S-phenyl-L-cysteine (SPMA), N-acetyl-S-benzyl-cysteine (SBMA), p-nitrophenol (PNP), methylhippuric acids (MHA), p-Aminophenol (PAP), mandelic acid (MA), phenylglyoxylic acid (PGA) and 1-hydroxypyrene (1-OHP) in urine.

Methods: After adding 20 μL of β-glucuronidase and 1 mL ammonium acetate buffer solution in 1 mL of urine, the sample was digested in a 37 ℃ incubator for 20 h. After digestion, the enzymatic hydrolysate was purified by PRIME HLB solid phase extraction column.

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Article Synopsis
  • The study aimed to develop an efficient assay for measuring 8-oxo-2'-deoxyguanosine and cotinine in human urine using hydrophilic chromatography tandem mass spectrometry (HILIC-MS/MS) with isotope dilution.
  • The method involved diluting urine samples, filtering, and analyzing them with ultra-performance liquid chromatography (UPLC-MS/MS) under controlled conditions, resulting in reliable detection limits and high recovery rates.
  • The findings indicated significant differences in tobacco exposure between active and passive smokers, with higher levels of cotinine and tobacco-specific nitrosamines found in the urine of active smokers, and a strong positive correlation between tobacco smoke exposure and nitrosamine intake.
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Objective: To develop a method for detecting nicotine and cotinine in hair by hydrophilic interaction chromatography tandem mass spectrometry.

Methods: Hair samples were hydrolyzed in sodium hydroxide solution before extraction with dichloromethane. The samples were blown to dry with nitrogen and dissolved with mobile phase.

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  • Cordycepin, a derivative of adenosine from the Cordyceps militaris fungus, has shown potential antitumor effects against colorectal cancer (CRC), but its mechanisms are not fully understood.
  • The study used HCT116 colon cancer cell lines to examine how cordycepin induces apoptosis (cell death) and found that it significantly reduced cell viability in a dose-dependent manner, particularly affecting cells with the Bax protein present.
  • Results indicated that cordycepin promotes the translocation of Bax to mitochondria, leading to the release of cytochrome c and triggering apoptosis, suggesting its potential as a new treatment option for CRC.
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Herein, a gas-sensitive functional nanomaterial was constructed by confining Tb(acac)(HO) (acac = acetylacetone) in the space of the metal organic framework ZIF-8. This functional nanomaterial can realize a gas-solid state aldol condensation reaction, even at room temperature and without the use of a catalyst. In the reaction process, formaldehyde (FA) gas molecules can invalidate the antenna effect of the acac ligands, and it can therefore act as an ultrasensitive FA gas remover and detector (limit of detection value = 49 ppb).

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Control of E2F1 activity is restricted via its interactions with RB1 and HDAC1. However, the detailed regulatory mechanisms underlying the E2F1/HDAC1 complex remain elusive. Here, we report that Nemo-like kinase (NLK) boosts cell cycle progression, which facilitates tumor development by releasing the E2F1 protein from HDAC1.

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The role of HIF-2α in hepatocellular carcinoma (HCC) is unclear. The aim of the present study was to investigate the expression pattern and role of HIF-2α in HCC patients. Immunohistochemical staining and western blotting analyses were applied to detect the protein level of HIF-2α in 206 paired HCC and peritumoral tissues.

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Article Synopsis
  • The study investigates the prognosis of hepatocellular carcinoma (HCC) patients with cirrhosis (HCC-C) compared to those without cirrhosis (HCC-NC).
  • Long-term survival outcomes are better for HCC-NC patients; certain risk factors like poor liver function and tumor characteristics influence survival rates differently between the two groups.
  • Findings suggest that HCC-C patients benefit significantly from antiviral treatments post-surgery, highlighting the need for tailored approaches to manage HCC based on cirrhosis status.
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A spectrum-tunable ground scenery spectrum radiation source, using LEDs and bromine tungsten lamp as luminescence media, was introduced. System structure and control of the spectrum radiation source was expounded in detail. In order to simulate various ground scenery spectrum distribution with different shapes, a ground scenery spectral database was established in the control system.

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A method of determining relative spectral responsivity of photodetector by LED-based spectrum-tunable integrating sphere source is put forward, and the measuring principle and algorithm are exhaustively described. In the course of calculation, the radiant transmission integral equation was changed into summation formula, and the degree of approximation between integral value and summation value is related to the selected wavelength interval. The differences between integral value and summation value in different wavelength intervals of Si photodiode and CCD were simulated and analyzed.

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The present paper introduced a spectral calibration method to calibrate a large aperture infrared radiation facility. We developed a radiometer which consisted of optical system, infrared detectors(cavity pyroelectric detector and HgCdTe detector 2 - 14 microm), fine mechanical modulator, lock in amplifier, signal processor, etc. At first, we analyzed the method on how to measure the spectral calibration of the large aperture infrared radiometer, and established the spectral calibration facility.

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