Publications by authors named "Beibei Meng"

Background: Melioidosis is a tropical infectious disease caused by , characterised by a high case fatality rate.

Objectives: We summarized the cases of melioidosis at Sanya People's Hospital in Hainan over the past eleven years. This information served as a reference for the epidemiological study, diagnosis, treatment, and prevention of melioidosis in China.

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Background: Immunocompromised patients with Lower Respiratory Tract Infections (LRTI) frequently encounter a diverse range of pathogenic infections, characterized by rapid disease progression and significant mortality rates due to reckless or excessive utilization of antibiotics. Therefore, it is crucial to promptly and accurately identify the causative microorganisms for pathogen diagnosis and clinical decision-making. The objective of this study is to evaluate the clinical applicability of metagenomic next-generation sequencing (mNGS) in the diagnosis and management of LRTI, as well as its impact on empirical antibacterial therapy for patients with varying immune statuses.

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Squalamine is an aminosterol from dogfish shark which has drawn attention, besides its antimicrobial activity, as a drug candidate in the treatment of Parkinson's disease due to its ability to prevent binding of α-synuclein to lipid membranes. To get insight into the mode of action of this steroid, we studied the influence of squalamine on lipid bilayers and whether it could inhibit the binding of a model peptide. Solid-state F NMR of labeled [KIGAKI] indicated that, indeed, this peptide no longer binds as a flexible chain to the bilayer in the presence of squalamine.

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Based on computer-aided drug design (CADD), the active groups of the known active small molecule compounds that can bind to EGFR target protein were analyzed through the molecular docking method. Then, 12 novel asiatic acid derivatives were synthesized by introducing active groups at ring A and C-28 positions of asiatic acid. The structures of these novel compounds were determined by NMR and MS.

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Based on the simulated docking of Epidermal growth factor receptor inhibitors with known active small molecule compounds, computer-aided drug design technology was used to analyze key amino acid fragments and determine the active groups binding with key sites. Then, twelve novel analogues of oleanolic acid (OA) were synthesized by introducing active groups at the C-3 and C-28 positions of OA. The structures of these novel analogues were confirmed by NMR and MS.

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To discovery novel VEGFR inhibitors, 12 novel asiatic acid derivatives were designed by computer-aided drug design (CADD) technology. Then, these novel asiatic acid derivatives were synthesized by introducing active groups at ring A and C-28 positions of asiatic acid. The structures of these novel analogues were confirmed by NMR and MS.

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A labeling strategy for in vivo F-MRI (magnetic resonance imaging) based on highly fluorinated, short hydrophilic peptide probes, is developed. As dual-purpose probes, they are functionalized further by a fluorophore and an alkyne moiety for bioconjugation. High fluorination is achieved by three perfluoro-tert-butyl groups, introduced into asparagine analogues by chemically stable amide bond linkages.

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The VEGF receptor is mock-coupled with a known active compound and the active groups of the inhibitor which can bind to VEGF were analyzed. Using asiatic acid as a lead compound, 10 novel skeleton candidate compounds were designed through introduction of the active groups onto the special location and synthesized simultaneously. Furthermore, the structure of these compounds was determined by H NMR, C NMR and MS and 9 compounds were identified as the new compounds.

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Asymmetric alkynylation of thiazolones and azlactones with alkynylbenziodoxolones as the electrophilic alkyne source catalyzed by thiourea phosphonium salt is described. By using thiazolones as nucleophiles, the desired alkyne functionalized thiazolones were obtained in 55-89% yields with 31-86% ee. Azlactones gave the desired products in comparable yields with lower enantioselectivities.

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A diastereo- and enantioselective propargylic substitution reaction between propargylic carbonates and α-substituted nitroacetates catalyzed by a Cu-pybox complex is described. This method allows the preparation of a series of non-proteinogenic quaternary α-amino acid precursors featuring two contiguous stereogenic centers and a terminal alkyne moiety in high yields with good to excellent diastereo- and enantioselectivities in most cases. The propargylated adducts were elaborated into a diverse set of quaternary α-amino acid derivatives.

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Polysaccharide nanoparticles are versatile functional materials used in drug delivery applications. Here we describe a method for the synthesis of β-1,3-glucan esters which show the formation of nanoparticles. Pyridine-soluble β-1,3-glucan formate was first synthesized as an intermediate and then reacted with various anhydrates to yield β-1,3-glucan acetate and hexaonate.

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