Publications by authors named "YueMei Chen"

Fifteen novel carbazole alkaloids, euchrestifolines A-O (1-15), were obtained from Murraya euchrestifolia. Their structures were elucidated by spectroscopic analysis, Mosher's ester, calculated ECD, and transition metal complex ECD methods. Notably, euchrestifolines A-C (1-3) are the first naturally occurring pyrrolidone carbazoles to be identified, while euchrestifolines D-F (4-6) represent rare carbazole alkaloids containing a phenylpropanyl moiety; euchrestifoline G (7) features a unique benzopyranocarbazole skeleton.

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  • * A case study details an unusual instance of NDI in a 50-year-old Chinese woman who developed symptoms after cervical cancer surgery, leading to a diagnosis through various tests and genetic analysis revealing a specific mutation.
  • * The patient improved significantly after a low-sodium diet and medication, highlighting the necessity of specialized tests to accurately diagnose and manage NDI, even in older females, where it's less common.
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  • The study used a two-sample bidirectional Mendelian randomization (MR) analysis to explore the connection between venous leg ulcers (VLUs) and knee osteoarthritis (KOA).
  • Multiple MR methods, including inverse variance weighted and others, showed no significant genetic association between VLUs and KOA, indicating that they do not influence each other.
  • The research concluded that there is no causal or reverse causal relationship between VLUs and KOA based on the genetic analysis performed.
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Background: Social support, which is a crucial external resource for cancer patients, was demonstrated to be a positive predictor of learned helplessness (LH). But it is far from clear whether and how social support decreases the LH in cancer patients. The purpose of present study is to detect the association between social support and LH and the role of individual resilience and self-efficacy in mediating this relationship.

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Cerebrospinal fluid (CSF)-based pathogen or biochemical testing is the standard approach for clinical diagnosis of various meningitis. However, misdiagnosis and missed diagnosis always occur due to the shortages of unusual clinical manifestations and time-consuming shortcomings, low sensitivity, and poor specificity. Here, for the first time, we propose a simple and reliable CSF-induced SERS platform assisted with machine learning (ML) for the diagnosis and identification of various meningitis.

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Background: Chronic infections by pathogenic microorganisms play a significant role in cancer development, disrupting the body's immune system and microenvironment. This interference impairs the body's ability to eliminate these microorganisms promptly, allowing them to persist by evading immune defenses.

Aims: This study aimed to explore how chronic pathogenic infections influence the immune microenvironment, impacting tumorigenesis, cancer progression, and treatment strategies.

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Background: This study aimed to explore the relationship between flavonoids intake and the prevalence and all-cause mortality of depressive symptoms in American adults.

Methods: Analyzing 2007-2008, 2009-2010, and 2017-2018 NHANES data, we examined the association between dietary flavonoid and depressive symptoms, including specific subclasses assessment and mortality outcomes tracking until December 31, 2019. Our methodology included weighted multivariate logistic regression, weighted cox proportional hazards regression and restricted cubic spline (RCS) models, supported by stratified and sensitivity analyses.

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The potential pesticide hazard to non-target organisms is a global concern. It is critical to develop the sensitive detection methods of multiple pesticides in various complex matrices. Here, benzene-1,3,5-tricarbaldehyde (BTCA) and 1,3,5-Tri (4-aminophenyl) benzene (TAPB) were employed as precursors for the in-situ growth of COF on the surface of amino-functionalized stainless steel wire (SS) via a solvothermal method.

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This study presented a nanoparticle-enhanced aptamer-recognizing homogeneous detection system combined with a portable instrument (NASPI) to quantify lipoarabinomannan (LAM). This system leveraged the high binding affinity of aptamers, the high sensitivity of nanoparticle cascade amplification, and the stabilization effect of dual stabilizers (fructose and histone), and used probe-Cu to achieve LAM detection at concentrations ranging from 10 ag mL to 100 fg mL, with a limit of detection of 3 ag mL using a fluorometer. It can also be detected using an independently developed handheld fluorometer or the red-green-blue (RGB) camera of a smartphone, with a minimum detection concentration of 10 ag mL.

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  • Microfluidic technology is transforming arterial thrombosis research by enabling the creation of artificial blood vessels and simulating blood flow dynamics, leading to better understanding of thrombus formation and platelet interactions.
  • This technology allows for precise manipulation of fluid flow, helping researchers explore how different shear forces and flow rates affect platelet behavior, which is crucial for understanding blood flow's physiological and pathological processes.
  • Despite the advancements in microfluidic systems, there is an urgent need for standardization, but the future looks promising for developing more versatile and automated solutions for antithrombotic therapies.
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Background: Miniaturized microplasma-based atomic emission spectrometry (AES) has been extensively used for element analysis in recent years due to the advantages of low power consumption, low gas consumption, relatively low manufacturing and running cost, and the potential for real-time and field analysis. However, few applications in bioassay detection have been reported based on microplasma AES systems because of their relatively low sensitivity and the absence of indirect analytical strategies. It is still a challenge to develop a simple, sensitive, and portable microplasma-based AES bioassay approach.

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Pyrethroid insecticides residues in water pose a critical threat to the environment from widespread production and overuse. Therefore, it is of major relevance to develop a sensitive and efficient method to detect pyrethroid insecticides in water. In this paper, a covalent organic framework (COF) with NHCO as the structural unit was synthesized using a simple condensation reaction of TTL (NH) and TDBA (COOH).

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Tobacco-specific nitrosamines (TSNAs) are probably carcinogenic disinfection byproducts eliciting health risk concerns. The determination and surveillance of TSNAs in water is still cumbersome due to the lack of advanced sample preparation methods. Herein, we prepared a solid phase microextraction (SPME) fiber coated with the molecularly imprinted polymer (MIP) sheathed mesoporous silica tube (MST) composite material, and developed a highly efficient, selective, and sensitive method for the determination of five TSNAs in water.

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Background: Risk stratification of patients with cervical cancer accompanied by positive lymph nodes (stage IIIC) (the 2018 International Federation of Gynecology and Obstetrics [FIGO] new staging system) yields a clinically heterogeneous group. In this study, we investigated the prognostic performance of the 2018 FIGO staging system for stage IIIC cervical cancer.

Methods: The study included patients with stage III cervical cancer based on the 2018 FIGO staging system, who visited Chongqing University Cancer Hospital between January 2011 and December 2014.

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Three new coumarins, integmarins A-C (1-3), and a new coumarin glycoside, integmaside A (4) were isolated from the leaves and stems of Micromelum integerrimum. Their structures were elucidated on the basis of 1D and 2D NMR and MS data, and their absolute configurations were assigned according to the ECD data of the in situ formed transition metal complexes and comparison of experimental and calculated ECD data. Compounds 1 and 2 are two rare coumarins with butyl and propyl moieties at the C-6 position; compound 3 is a novel coumarin with a highly oxidized prenyl group, and compound 4 is a rare bisdihydrofuranocoumarin glycoside.

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Objective: Diabetic nephropathy (DN) is a serious kidney-based complication of diabetes, wherein podocyte injury is deemed crucial in the development of early stage. Various miRNAs, as report goes, is involved in the pathogenesis of varieties of kidney diseases including DN. In this study, we found a target relationship between miR-30a-5p and Becn1, of which there are few studies about the role in podocyte injury.

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  • Ten new alkaloids, labeled integerrines A-J, were discovered from Micromelum integerrimum, including a unique racemic heterodimer and various biscarbazoles and aldoximes.
  • * The compounds were analyzed using chiral-phase HPLC to determine their configurations by matching experimental data with calculated ECD results.
  • * Four of these alkaloids showed moderate to weak cytotoxic effects on cancer cell lines, with IC values ranging from 14.1 to 67.5 μM.
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A new prenylated coumarin diglycoside, 6-prenylcoumarin-7---D-apiofuranosyl-(1→6)--D-glucopyranoside () and five known flavonoid glycosides () were isolated from the leaves and stems of . The structures of these isolates were elucidated based on comprehensive MS, UV, IR, and NMR spectroscopic data analysis and comparison with the data reported in literature. Compounds are obtained from the title plant for the first time.

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To improve CO adsorption performance of nanoparticle absorbents, a novel tertiary amine functionalized nano-SiO (NS-NR) was synthesized based on the 3-aminopropyltrimethoxysilane (KH540) modified nano-SiO (NS-NH) via methylation. The chemical structure and performances of the NS-NR were characterized through a series of experiments, which revealed that NS-NR can react with CO in water and nanofluid with low viscosity revealed better CO capture. The CO capture mechanism of NS-NR was studied by kinetic models.

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Chemical investigation of the traditional Chinese medicine, Murraya kwangsiensis, led to the isolation of 16 undescribed biscarbazole alkaloids, kwangsines A-M, two undescribed natural products, (+/-)-bispyrayafoline C, and 19 known monomeric analogues. (±)-Bispyrayafoline C and (±)-kwangsines A-C are four pairs of biscarbazole atropisomers, and they were separated by chiral HPLC to obtain the optically pure compounds. The structures of the undescribed compounds were elucidated on the basis of HRESIMS and NMR data analysis.

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To explore famous veteran traditional Chinese medicine( TCM) doctors' medication rules in treating spermatorrhea based on the medical cases about spermatorrhea collected from Hundred TCM Clinical Doctors of Hundred Years in China and Proven Cases and National Medical Master Test Case. Researchers extracted such data as medicinal and therapies from these cases according to the inclusion and exclusion criteria. Then,Excle 2010,SPSS Clementine 12.

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Phytochemical study on the roots and rhizomes of Notopterygium incisum resulted in the isolation of six new coumarins, notoptetherins A - F (1-6), and 20 known analogues (7-26). Their structures were elucidated on the basis of extensive analyses of NMR and HRMS data, and the absolute configurations of 5 and 6 were established by Mo(AcO)-induced CD and exciton chirality, respectively. Moreover, a biomimetic synthesis of 6 from 21 was employed to confirm its absolute configuration.

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Nine undescribed carbazole and quinoline alkaloids, named dunnines A-E, and 14 known analogues were isolated from the leaves and stems of Clausena dunniana. Their structures were elucidated on the basis of comprehensive analysis of NMR and HRMS spectroscopic data, and the absolute configurations were assigned via comparison of their specific rotations and calculated and experimental ECD data. (±)-Dunnines A-C and (±)-clausenawalline A are four pairs of biscarbazole atropisomers and (±)-dunnine D is a pair of dihydropyranocarbazole enantiomers.

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The open silica gel, ODS, and Sephadex LH-20 column chromatography, along with the semi-preparative HPLC was used to isolate and purify the chemical constituents from Murraya euchrestifolia. The structures of the isolates were elucidated by their physiochemical properties, NMR, and MS spectroscopic data, as well as comparison with literature data. Eighteen compounds were isolated from the CH2Cl2 fraction of the 95% aqueous EtOH extract of M.

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