Publications by authors named "Hai-Feng Chen"

Background: Yigu decoction (YGD) is a traditional Chinese medicine prescription for the treatment of osteoporosis, although many clinical studies have confirmed its anti-OP effect, but the specific mechanism is still not completely clear.

Methods: In this study, through the methods of network pharmacology and molecular docking, the material basis and action target of YGD in preventing and treating OP were analyzed, and the potential target and mechanism of YGD in preventing and treating OP were clarified by TMT quantitative protein and experiment.

Results: Network pharmacology and molecular docking revealed that the active components of YGD were mainly stigmasterol and flavonoids.

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Four alkaloid compounds including one new compound and three known ones were isolated and extracted from the 70% ethanol extract of Nelumbinis Folium by silica gel column chromatography, octadecylsilyl(ODS) column chromatography and preparative high-performance liquid chromatography. Their structures were identified by nuclear magnetic resonance spectroscopy, high-resolution mass spectrometry, circular dichroism and other methods. Compound 1 was identified as a new compound and named as lotustine B(1).

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One undescribed xanthone, hypersine H (1), together with three known analogs, 3,7-dihydroxy-1-methoxyxanthone (2), 1,7-dihydroxy-5,6-dimethoxyxanthone (3), and 1,5-dihydroxy-6,7-dimethoxyxanthone (4), were isolated from the whole plant of Hypericum elodeoides Choisy. Their structures, including absolute configurations, were unambiguously elucidated by HR-ESI-MS, extensive NMR spectroscopy, and quantum chemical calculation of electronic circular dichroism (ECD) method. Moreover, the anti-neuroinflammation activities of isolated compounds were evaluated.

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  • Al-doped Ga2O3 microbelts were developed using carbothermal reduction, with impressive dimensions of 20 to 154 μm in width and up to 2 mm in length.
  • The resulting photoconductive UV detectors demonstrated outstanding performance at 185 nm, achieving a high photocurrent of 192.07 μA and an exceptional light-to-dark current ratio of 1.23×10^9.
  • The study highlights the potential of Al-doped Ga2O3 microbelts for VUV photodetectors, showcasing superior selectivity and responsivity compared to detectors targeting longer UV wavelengths.
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Intrinsically disordered proteins (IDPs) lack stable tertiary structures under physiological conditions, yet play key roles in biological processes and associated with human complex diseases. Their conformational characteristics and high content of charged residues make the use of polarizable force fields an advantageous for simulating IDPs. The Drude2019IDP polarizable force field, previously introduced, has demonstrated comprehensive enhancements and improvements in dipeptides, short peptides, and IDPs, achieving a balanced sampling between IDPs and structured proteins.

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  • - The study discovered 12 new compounds called filicinic acid-based meroterpenoids (1-12) from Hypericum elodeoides, characterized by their unique ring structures identified using advanced spectroscopic techniques and molecular calculations.
  • - Biological tests indicated that compounds 1a, 5a, and 11b can activate a specific receptor (RXRα) and increase the expression of a protein (ABCA1) that is involved in cholesterol transport.
  • - Among these, compound 1a showed a strong potential for treating Alzheimer's disease by promoting the clearance of β-amyloid plaques through its interaction with RXRα, as supported by various assays including molecular docking studies.
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  • The transition between excited and ground states in RNA and strand slippage are crucial for transcription and translation processes.
  • Current experimental techniques don't fully capture RNA's complex dynamic structures, making molecular dynamics simulations, particularly with a new RNA base-specific force field (BSFF2), valuable for better understanding.
  • BSFF2 has been validated for its accuracy and efficiency in RNA folding and dynamics, helping to provide insights into strand slippage and potentially aiding in RNA-based drug design and therapies.
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In the process of searching for anti-breast cancer agents, five sesquiterpene lactones (1-5), including two previously undescribed ones, yjaponica B-C (1-2), were isolated from the herb of Youngia japonica. Their structures were elucidated by spectroscopic data analyses and Marfey's method. Cytotoxic activities of all compounds against A549, U87, and 4T1 cell lines were tested using the CCK8 assay.

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Recent studies have shifted the spotlight from adult disease to gametogenesis and embryo developmental events, and these are greatly affected by various environmental chemicals, such as drugs, metabolites, pollutants, and others. Growing research has highlighted the critical importance of identifying and understanding the roles of chemicals in reproductive biology. However, the functions and mechanisms of chemicals in reproductive processes remain incomplete.

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The aggregation of superoxide dismutase 1 (SOD1) results in amyloid deposition and is involved in familial amyotrophic lateral sclerosis, a fatal motor neuron disease. There have been extensive studies of its aggregation mechanism. Noncanonical amino acid 5-cyano-tryptophan (5-CN-Trp), which has been incorporated into the amyloid segments of SOD1 as infrared probes to increase the structural sensitivity of IR spectroscopy, is found to accelerate the overall aggregation rate and potentially modulate the aggregation process.

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Disordered proteins are conformationally flexible proteins that are biologically important and have been implicated in devastating diseases such as Alzheimer's disease and cancer. Unlike stably folded structured proteins, disordered proteins sample a range of different conformations that needs to be accounted for. Here, we treat disordered proteins as polymer chains, and compute a dimensionless quantity called instantaneous shape ratio (R), as R = R/R, where R is end-to-end distance and R is radius of gyration.

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Protein design is central to nearly all protein engineering problems, as it can enable the creation of proteins with new biological functions, such as improving the catalytic efficiency of enzymes. One key facet of protein design, fixed-backbone protein sequence design, seeks to design new sequences that will conform to a prescribed protein backbone structure. Nonetheless, existing sequence design methods present limitations, such as low sequence diversity and shortcomings in experimental validation of the designed functional proteins.

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Molecular dynamics simulations play a pivotal role in elucidating the dynamic behaviors of RNA structures, offering a valuable complement to traditional methods such as nuclear magnetic resonance or X-ray. Despite this, the current precision of RNA force fields lags behind that of protein force fields. In this work, we systematically compared the performance of four RNA force fields (, , , ) across diverse RNA structures.

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Fourteen sesquiterpenes, including one undescribed sesquiterpene lactone, were isolated from Youngia japonica, and their structures were identified by NMR, HRESIMS, ECD and calculated ECD. Cytotoxic activities of all isolates against A549, HeLa, and 4 T1 cell lines were detected by CCK8 assay. Among them, 2 showed obvious cytotoxic activity against A549 cells.

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Motivation: Proteins found in nature represent only a fraction of the vast space of possible proteins. Protein design presents an opportunity to explore and expand this protein landscape. Within protein design, protein sequence design plays a crucial role, and numerous successful methods have been developed.

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Four undescribed coumarin derivatives, ficusalt A (1) and ficusalt B (2), a pair of racemic coumarins, (±) ficudimer A (3a/3b), along with ten known amides, were isolated from the roots of Ficus hirta. Their structures were elucidated by several spectroscopic data analyses, including HRESIMS, NMR, and X-ray single-crystal diffraction. The cytotoxic activities of all compounds against HeLa, HepG2, MCF-7, and H460 cell lines were detected using the MTT assay.

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The biological function of proteins is determined not only by their static structures but also by the dynamic properties of their conformational ensembles. Numerous high-accuracy static structure prediction tools have been recently developed based on deep learning; however, there remains a lack of efficient and accurate methods for exploring protein dynamic conformations. Traditionally, studies concerning protein dynamics have relied on molecular dynamics (MD) simulations, which incur significant computational costs for all-atom precision and struggle to adequately sample conformational spaces with high energy barriers.

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Cyclic di-adenosine monophosphate (c-di-AMP) is a newly identified prokaryotic cyclic dinucleotide second messenger well elucidated in bacteria, while less studied in archaea. Here, we describe the enzymes involved in c-di-AMP metabolism in the hyperthermophilic archaeon Pyrococcus yayanosii. Our results demonstrate that c-di-AMP is synthesized from two molecules of ATP by diadenylate cyclase (DAC) and degraded into pApA and then to AMP by a DHH family phosphodiesterase (PDE).

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An unusual secomeroterpenoid, dysambiol (), was isolated from a sp. marine sponge collected from the South China Sea. Dysambiol features an unprecedented secomeroterpene scaffold with a rare lactone bridge.

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Background: Disordered gut microbiota (GM) structure and function may contribute to osteoporosis (OP). This study explores how traditional Chinese medicine (TCM) intervention affects the structure and function of the GM in patients with OP.

Method: In a 3-month clinical study, 43 patients were randomly divided into two groups receiving conventional treatment and combined TCM (Yigu decoction, YGD) treatment.

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Intrinsically disordered proteins (IDPs) play a critical role in many biological processes. Due to the inherent structural flexibility of IDPs, experimental methods present significant challenges for sampling their conformational information at the atomic level. Therefore, molecular dynamics (MD) simulations have emerged as the primary tools for modeling IDPs whose accuracy depend on force field and water model.

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Protein phosphorylation, catalyzed by kinases, is an important biochemical process, which plays an essential role in multiple cell signaling pathways. Meanwhile, protein-protein interactions (PPI) constitute the signaling pathways. Abnormal phosphorylation status on protein can regulate protein functions through PPI to evoke severe diseases, such as Cancer and Alzheimer's disease.

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Article Synopsis
  • A study investigated the connection between a healthy lifestyle and the risk of developing rheumatoid arthritis (RA) by analyzing metabolic signatures in a large group of participants from the UK Biobank.
  • The research focused on five healthy lifestyle factors: diet, exercise, smoking status, alcohol consumption, and body mass index, finding that a specific metabolic signature linked to these factors significantly reduced RA risk.
  • The results suggested that the metabolic signature not only correlates strongly with healthy lifestyles but also mediates approximately 64% of the protective effects against RA, indicating both observational and genetic evidence for this relationship.
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Intrinsically disordered proteins (IDPs) account for more than 50% of the human proteome and are closely associated with tumors, cardiovascular diseases, and neurodegeneration, which have no fixed three-dimensional structure under physiological conditions. Due to the characteristic of conformational diversity, conventional experimental methods of structural biology, such as NMR, X-ray diffraction, and CryoEM, are unable to capture conformational ensembles. Molecular dynamics (MD) simulation can sample the dynamic conformations at the atomic level, which has become an effective method for studying the structure and function of IDPs.

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Allosteric modulators are important regulation elements that bind the allosteric site beyond the active site, leading to the changes in dynamic and/or thermodynamic properties of the protein. Allosteric modulators have been a considerable interest as potential drugs with high selectivity and safety. However, current experimental methods have limitations to identify allosteric sites.

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