Publications by authors named "Lixin Duan"

Introduction: Timosaponins, as steroidal saponins, are the primary active constituents and quality biomarkers in Anemarrhena asphodeloides Bunge. Despite their significance, the biosynthetic pathways of timosaponins have not been thoroughly investigated.

Objectives: This study aims to delineate the biosynthetic pathway of timosaponins in A.

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  • * The study identified key enzyme genes involved in the triterpenoid metabolic pathways using transcriptome sequencing and synthetic biology, particularly focusing on two 2,3-oxidosqualene cyclases and two cytochrome P450s.
  • * Researchers successfully reconstructed the biosynthetic pathway for ursane and oleanane-type triterpenoids in a yeast host, detailing the enzymatic reactions necessary for producing important compounds like ursolic acid and oleanolic acid.
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Typical dammarane-type ginsenosides are well-known tetracyclic triterpenoids with significant pharmacological effects including antitumor, cardiovascular protection, and neuroprotection. Polyene-type ginsenosides exhibit stronger biological activities than common ginsenosides; however, their contents are low, and most are converted from ginsenosides through a series of processing steps, resulting in higher preparation costs. In this study, a dammaradienol synthase, AarOSC20433, was identified for the first time from H.

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  • The study investigates how different types of vegetation, particularly moss, affect soil organic carbon (SOC) levels in urban forests.
  • Moss-covered soils showed significantly higher SOC content compared to bare soils across various forest types, emphasizing moss's role in carbon accumulation.
  • Key environmental factors like canopy density, moss biomass, and soil moisture significantly influenced SOC content, suggesting the need for further research on bryophytes in urban ecosystems.
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  • H. Lév. & Vaniot is a key traditional Chinese medicinal plant with valuable volatile oils, particularly sesquiterpenoids, which are under-researched in terms of their biosynthesis.
  • The study successfully identified four -caryophyllene synthases and developed a high-yield engineered cell factory that achieved a remarkable production level of -caryophyllene at 15.6 g/L through fed-batch fermentation.
  • This achievement marks the highest yield of -caryophyllene produced in yeast to date, paving the way for its potential industrial-scale production.
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Water-soluble smart materials with multi-stimuli-responsiveness and ultra-long room-temperature phosphorescence (RTP) have garnered broad attention. Herein, a water-soluble terpyridine zinc complex (MeO-Tpy-Zn-OAc), featuring a simple donor-π-acceptor (D-π-A) structure is presented, which responds to a variety of stimuli, including changes in solvents, pH, temperature, and the addition of amino acids. Notably, MeO-Tpy-Zn-OAc functions as a fluorescence probe, capable of visually and selectively discriminating aspartate or histidine among other common amino acids in water.

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In medical image segmentation, it is often necessary to collect opinions from multiple experts to make the final decision. This clinical routine helps to mitigate individual bias. However, when data is annotated by multiple experts, standard deep learning models are often not applicable.

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Ecosystem stability arises from the interplay of species diversity, environmental conditions, and external disturbances. Understanding the structure of plant communities, interspecific relationships, and community stability in urban ecosystems is fundamental to ecological restoration and community development. This study utilized the karst city of Guiyang as a case study and employed the diversity index, variance ratio method (), -test, Pearson correlation test, Spearman rank correlation test, M.

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(+)-Ambrein is the primary component of ambergris, a rare product found in sperm whales (Physeter microcephalus). Microbial production using sustainable resources is a promising way to replace animal extraction and chemical synthesis. We constructed an engineered yeast strain to produce (+)-ambrein de novo.

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  • Artemisia argyi is a medicinal plant known for its health benefits due to its various triterpenoids that have anti-viral, anti-cancer, and anti-oxidant properties.
  • The study focuses on isolating and identifying four genes related to the 2,3-oxidosqualene cyclase (OSC) family, which are crucial for the triterpenoid biosynthesis pathway in A. argyi.
  • Three of the isolated OSC genes were shown to produce different triterpenoids through a yeast expression system, enhancing knowledge of how these valuable compounds are synthesized in the plant.
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Background: Odorant-binding proteins (OBPs) in insects are key to detection and recognition of external chemical signals associated with survival. OBP7 in Spodoptera frugiperda's larval stage (SfruOBP7) may search for host plants by sensing plant volatiles, which are important sources of pest attractants and repellents. However, the atomic-level basis of binding modes remains elusive.

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  • Medical segmentation can be ambiguous, so expert clinical groups annotate images to reduce personal bias, often using majority voting to combine their labels.
  • The proposed Diagnosis-First segmentation Framework (DiFF) enhances medical image segmentation by focusing on disease diagnosis as a standard to resolve uncertainty from different annotators.
  • DiFF demonstrates its effectiveness in three medical tasks—optical disc/cup segmentation, thyroid nodule segmentation, and skin lesion segmentation—showing improved performance over previous methods in helping with disease diagnosis.
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β-Amyrin synthase (bAS) is a representative plant oxidosqualene cyclase (OSC), and previous studies have identified many functional residues and mutants that can alter its catalytic activity. However, the regulatory mechanism of the active site architecture for adjusting the catalytic activity remains unclear. In this study, we investigate the function of key residues and their regulatory effects on the catalytic activity of β-amyrin synthase (GgbAS) through molecular dynamics simulations and site-directed mutagenesis experiments.

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Background: Immunoglobulin A nephropathy (IgAN) is one of the leading causes of end-stage kidney disease (ESKD). Many studies have shown the significance of pathological manifestations in predicting the outcome of patients with IgAN, especially -score of Oxford classification. Evaluating prognosis may be hampered in patients without renal biopsy.

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Deep models have achieved state-of-the-art performance on a broad range of visual recognition tasks. Nevertheless, the generalization ability of deep models is seriously affected by noisy labels. Though deep learning packages have different losses, this is not transparent for users to choose consistent losses.

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Two previously undescribed phloroglucinol derivatives [(±) evolephloroglucinols A and B], five unusual coumarins [evolecoumarins A and B and (±) evolecoumarins C-E], and one novel enantiomeric quinoline-type alkaloid [(±) evolealkaloid A], along with 20 known compounds, were isolated from the EtOH extract of the roots of Evodia lepta Merr. Their structures were elucidated by extensive spectroscopic analyses. The absolute configurations of the undescribed compounds were determined by X-ray diffraction or computational calculations.

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Many functionally promiscuous plant 2,3-oxidosqualene cyclases (OSCs) have been found, but complete functional reshaping is rarely reported. In this study, we have identified two new plant OSCs: a unique protostadienol synthase (PDS) and a common cycloartenol synthase (CAS) from (Sam.) Juzep.

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Background: Anorectal diseases are common in the population and include internal, external, and mixed hemorrhoids. Although hemorrhoid surgery is a brief operation, anesthesia, anesthetic drugs, drug concentrations, and anesthesia level control are closely related to postoperative uroschesis. For hemorrhoid surgery, a single spinal block with ropivacaine is commonly used that blocks the S2-S4 parasympathetic nervous system, which in turn governs the voiding reflex, causing postoperative urinary retention; this affects the recovery of patients.

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(L.), a traditional edible and medicinal crop, contains diverse triterpenes with multiple pharmacological properties. However, the biosynthesis of triterpenes in perilla remains rarely revelation.

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The basic leucine zipper (bZIP) transcription factor family plays an important role in various biological processes in plants. Andrographis paniculata (Burm.f) Nees, belonging to the family Acanthaceae, has been widely used as an important traditional herb with a wide range of pharmacological activities, such as antivenom, antiretroviral, anticancer and so on.

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Instant visualization of latent fingerprints is developed by using a series of water-soluble terpyridine zinc complexes as aggregation-induced emission probes in pure water, under UV light or ambient sunlight. By simply soaking, or spraying with an aqueous solution of the probe, bright yellow fluorescence images with high contrast and resolution are readily developed on various surfaces including tinfoil, glass, paper, steel, leather, and ceramic tile. Remarkably, latent fingerprints can be visualized within seconds including details of whorl and sweat pores.

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is an important economic plant that is rich in lipophilic triterpenols with pharmacological activities including antiallergic, anti-inflammatory, and anticancer activities. However, the key enzymes related to triterpene biosynthesis have seldom been studied in . Oxidosqualene cyclases (OSCs) are the rate-limiting enzymes related to triterpene biosynthesis.

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Cantor are precious medicinal animals in traditional Chinese medicine (TCM). Bufadienolides as the major pharmacological components are generated from the venomous glands of . Bufadienolides are one type of cardiac aglycone with a six-member lactone ring and have properties of antitumor, cardiotonic, tonsillitis, and anti-inflammatory.

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Six unidentified C steroidal glycosides, cynwallosides A-F, as well as twenty-two known compounds, were isolated from the roots of Cynanchum wallichii Wight. The structures of cynwallosides A-F were determined by spectroscopic analysis and acidic hydrolysis. Most of these twenty-eight compounds were found to significantly reverse drug resistance in both the MCF-7/ADR and HepG2/ADM cell lines by suppressing P-gp protein expression.

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