Publications by authors named "Guo-yuan Zhu"

Although electrochemical biosensors have been developed to detect multiple microRNAs (miRNAs) simultaneously through loading different capture probes, high surface-induced perturbation and competition among probes have reduced the detection sensitivity. To address these challenges, a trefoil DNA capture probe (TDCP) was designed for microRNA-21 (miR-21) and microRNA-16 (miR-16) detection simultaneously. The TDCP exhibits a stable structure, low spatial resistance, and integral rigidity, which decreases high surface-induced perturbations and competition to improve the accessibility of the target miRNA.

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Five undescribed diterpenoids, serranins A-E (-), and four novel triterpenoids, serratic acids A-D (-), along with 32 known terpenoids (-) were isolated from the aerial parts of . The planar structures of - and their relative configurations were established on the basis of extensive spectroscopic analysis. Structurally, compounds - are the first examples of 18,19--ursane -coumaric or ferulic esters, while compounds - further enriched the plant's diterpene profile.

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Lactate accumulation and macrophage infiltration are pivotal features of both chronic inflammation and cancer. Lactate, once regarded merely as an aftereffect of glucose metabolism, is now gaining recognition for its burgeoning spectrum of biological roles and immunomodulatory significance. Recent studies have evidenced that macrophages display divergent immunophenotypes in different diseases, which play a pivotal role in disease management by modulating macrophage polarization within the disease microenvironment.

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Carabranolides present characteristic NMR resonances for the cyclopropane moiety, which distinctly differ from those of other compounds and were used for an NMR-guided isolation in this study. As a result, 11 undescribed carabranolides (-), along with five known ones (-), were isolated from the fruits of L. Compounds - are new esters of carabrol at C-4 with different carboxylic acids.

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Persimmon (Diospyros kaki) leaf is widely used as a tea substitute in East Asia, offering potential health benefits. Although studies have highlighted their effects on hyperpigmentation disorders, the active components remain unidentified. This study introduces a novel approach combining LC-MS/MS-based molecular networking with AlphaFold2-enabled virtual screening to expedite the identification of bioactive components in persimmon leaf.

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Olibanum, a golden oleo-gum resin from species in the genus ( family), is a famous traditional herbal medicine widely used around the world. Previous phytochemical studies mainly focused on the non-polar fractions of olibanum. In this study, nine novel diterpenoids, boswellianols A-I (-), and three known compounds were isolated from the polar methanolic fraction of the oleo-gum resin of .

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Steroidal alkaloids are the main bioactive components of the bulbs of Fritillaria, which have been used as traditional Chinese medicine, known as "Beimu", for the treatment of cough for thousands of years in China. Cough and dyspnea are the most common symptoms observed in patients with pulmonary fibrosis. However, the antifibrotic activity of steroidal alkaloids has not been reported yet.

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To mine fascinating molecules from the rhizomes of Atractylodes chinensis, the known molecular formula of atrachinenin A was used as a bait to search LC-HRMS data in different subfractions. Sixteen new meroterpenoids, atrachinenins D-S (1-16) including three unprecedented carbon skeletons (1-5) and eleven new oxygen-bridged hybrids (6-16) were obtained by the targeted isolation. Their structures and absolute configurations were elucidated by the spectroscopic data and electronic circular dichroism (ECD) calculations.

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Nonapoptotic ferroptosis is a promising cancer treatment which offers a solution to the multidrug resistance of conventional apoptosis-induced programmed cancer cell death therapies. Reducing intracellular glutathione (GSH) is essential for inducing excess ROS and has been considered a crucial process to trigger ferroptosis. However, treatments reducing GSH alone have not produced satisfactory effects due to their restricted target.

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Bioactive triterpenes feature complex fused-ring structures, primarily shaped by the first-committed enzyme, 2,3-oxidosqualene cyclases (OSCs) in plant triterpene biosynthesis. Triterpenes with B,C-ring-opened skeletons are extremely rare with unknown formation mechanisms, harbouring unchartered chemistry and biology. Here, through mining the genome of Chenopodium quinoa followed by functional characterization, we identified a stress-responsive and neofunctionalized OSC capable of generating B,C-ring-opened triterpenes, including camelliol A and B and the novel (-)-quinoxide A as wax components of the specialized epidermal bladder cells, namely the quinoxide synthase (CqQS).

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Five undescribed sesquiterpenoid dimers, aucklandiolides A-E (1-5), one new sesquiterpenoid glycoside, β-cyclocostunolide-15-β-D-glucopyranoside (6), and seventeen known analogues (7-23) were isolated from the roots of Aucklandia costus. Their structures were elucidated by comprehensive HRESIMS and NMR spectroscopic data analysis, and their configurations were confirmed by the computational calculations of ECD and NMR chemical shifts. Aucklandiolides A and B are the first examples of dimeric sesquiterpenoids with a unique 6/6/6/5/6/6 ring system originated from a proposed Diels-Alder cycloaddition between two eudesmane sesquiterpenoids.

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Alcoholism is a worldwide health problem, and diseases caused by alcoholism are killing people every year. is a traditional Chinese medicine used to relieve hangovers. However, whether its bioactive components improve alcohol metabolism is not clear.

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Acetamiprid is poisonous to mammals due to severe acetamiprid-induced oxidative stress that could cause mitochondrial dysfunctions, lipid and protein oxidation, inflammation, apoptosis, and DNA damage. Evidence has accumulated for the role of oxidative stress in changing structures and functions of transfer RNAs (tRNAs) by inducing tRNA cleavage, reprogramming tRNA modifications and impairing aminoacyl-tRNA synthetase editing sites. However, the impact of acetamiprid-induced oxidative stress on tRNA is still unknown.

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Amethystoidesic acid (), a triterpenoid with an unprecedented 5/6/6/6 tetracyclic skeleton, and six undescribed diterpenoids, amethystoidins A-F (-), were isolated from the rhizomes of along with 31 known di- and triterpenoids (-). Their structures were fully elucidated via extensive spectroscopic analysis including 1D and 2D NMR, high-resolution electrospray ionization mass spectrometry (HRESIMS), and electronic circular dichroism (ECD) calculations. Compound is the first example of a triterpenoid possessing a rare ring system (5/6/6/6) derived from a contracted A-ring and the 18,19--E-ring of ursolic acid.

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Article Synopsis
  • The current difficulties in mass spectrometry for analyzing nucleic acids stem from their high polarity and low signal intensity, hindering drug quality control and DNA/RNA studies.
  • A new labeling method using -(tert-butyldimethylsilyl)--methyl-trifluoroacetamide (MTBSTFA) enhances oligonucleotide detection by providing strong retention and clear data without harmful byproducts.
  • This method improves RNA analysis by effectively profiling tRNA and identifying modified bases, revealing significant findings related to nonalcoholic fatty liver disease in cell studies.
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Lung cancer is the leading cause of cancer-related death worldwide. The development of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) and immune checkpoint inhibitors (ICIs) has brought favorable survival benefits to patients with non-small-cell lung cancer (NSCLC); unfortunately, acquired drug resistance remains a major barrier to the treatment of NSCLC. Recent studies have demonstrated that the transcriptional co-activator with a PDZ-binding motif (TAZ, also called WWTR1) induces tumor immune evasion by directly modulating the expression of programmed death ligand 1 (PD-L1), a key therapeutic target for checkpoint immunotherapy.

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Chlorfortunones A () and B (), two novel sesquiterpenoid dimers, were isolated from the roots of . Their structures were elucidated by spectroscopic analysis and X-ray diffraction analysis. Compounds and represent a new type of sesquiterpenoid dimer possessing an unprecedented 3/5/6/6/6/5 hexacyclic system with a unique dispiro[4,2,5,2]pentadecane-6,10,14-trien moiety.

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("Huang-Qin" in Chinese) is a well-known traditional herbal medicine and popular dietary supplement in the world, extensively used in prescriptions of TCMs as adjuvant treatments for coronavirus pneumonia 2019 (COVID-19) patients in China. According to the differences in its appearance, can be classified into two kinds: ZiQin (1∼3 year-old with hard roots) and KuQin (more than 3 year-old with withered pithy roots). In accordance with the clinical theory of TCM, KuQin is superior to ZiQin in cooling down the heat in the lung.

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(±)-Decumicorine A (1) and (±)-epi-decumicorine A (2), two pairs of enantiomeric isoquinoline alkaloids featuring a novel phenylpropanoid-conjugated protoberberine skeleton, were isolated and purified from the rhizomes of Corydalis decumbens. The separation of (±)-1 and (±)-2 was achieved by chiral HPLC to produce four optically pure enantiomers. The structures and absolute configurations of compounds (-)-1, (+)-1, (-)-2, and (+)-2 were elucidated by spectroscopic analysis, ECD calculations, and X-ray crystallographic analyses.

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The seed of Houtt (nutmeg) is one of the important spices that have been extensively used in the culinary, food, beverage, and also in medicinal products industry. Previous phytochemical studies on nutmeg were mainly focused on lignans and neolignans. However, the other constituents have been poorly studied.

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As a characteristic transcription factor in solid tumors, hypoxia inducible factor-1 (HIF-1) acts as a master regulator in breast cancer progression. Cryptolepine, as a natural alkaloid, noticeably inhibited HIF-1 transcriptional activity and decreased the protein expression of hypoxia-induced HIF-1α in breast cancer cells. Further study showed that cryptolepine blocked HIF-1-mediated glycolysis and suppressed the expression of multiple glycolysis enzymes, resulting in a decrease in ATP production in hypoxic T47D and 4T1 cells.

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Platycodon grandiflorus is a well-known edible and medicinal plant that has been developed for dietary supplements or functional foods to relieve pulmonary disorders. Platycosides are the main active constituents of P. grandiflorus with multiple pharmacological activities.

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Ten new alkaloids, calycindaphines A-J (1-10), together with seventeen known alkaloids were isolated from the roots of . Their structures were established by extensive spectroscopic methods and compared with data from literature. Compound 1 is a novel alkaloid with a new rearrangement C skeleton with the 5/8/7/5/5 ring system.

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