Five undescribed lignans, cleiseberharnins A-D (1-4), cleiseberharside A (5) were isolated from the fruits of Cleistanthus eberhartii (Phyllanthaceae), together with six known aryltetralin lignans, cleistantoxin (6), picroburseranin (7), neocleistantoxin (8), 7-hydroxypicropolygamain (9), cleisindoside D (10), and cleisindoside A (11). Their structures and relative configurations were established by analysis of HRESIMS and NMR data, and quantum chemical calculations of J coupling constants. The absolute configurations of 1-5 were determined by analysis of their experimental CD spectra and comparison with calculated electronic circular dichroism (ECD) spectra.
View Article and Find Full Text PDFOne novel chromanone acid derivative, namely inocalophylline C (), together with one known compound calophyllolide (), were isolated from the methanolic extract of nut oil resin of L., a medicinal plant widely distributed in Vietnam. The isolated compound structures were elucidated by spectroscopic methods and the absolute configuration of was established by the single-crystal X-ray crystallography as ethyl () 3-(()-4-hydroxy-2,3-dimethyl-6-(()-5-methyl-2-(prop-1-en-2-yl)hex-4-en-1-yl)-6-(3-methylbut-2-en-1-yl)-5,7-dioxo-3,5,6,7-tetrahydro-2-chromen-8-yl)-3-phenylpropanoate.
View Article and Find Full Text PDFThe IL-6/IL-6R or IL-6/GP130 protein-protein interactions play a significant role in controlling the development of chronic inflammatory diseases, such as rheumatoid arthritis, Castleman disease, psoriasis, and, most recently, COVID-19. Modulating or antagonizing protein-protein interactions of IL6 binding to its receptors by oral drugs promises similar efficacy to biological therapy in patients, namely monoclonal antibodies. In this study, we used a crystal structure of the Fab part of olokizumab in a complex with IL-6 (PDB ID: 4CNI) to uncover starting points for small molecule IL-6 antagonist discovery.
View Article and Find Full Text PDFAcrAB-TolC tripartite efflux pump, which belongs to the RND superfamily, is a main multi-drug efflux system of () because of the broad resistance on various antibiotics. With the discovering of efflux pump inhibitors (EPIs), a combination between these and antibiotics is one of the most promising therapies. Therefore, building a virtual screening model with prediction capacities for the efflux pump inhibitory activities of candidates from DrugBank and ZINC15 dataset, is one of the key goals of this project.
View Article and Find Full Text PDFThe role of interleukin-8 (IL-8) and its receptor CXCR2 in inflammatory responses and tumor development and progression has been well documented. Our study aims to discover novel compounds as CXCR2 antagonists to block the IL-8 signaling pathway using an drug design. Herein, a structure-based pharmacophore model was developed based on the crystal structure of inactive CXCR2 in a complex with an allosteric inhibitor.
View Article and Find Full Text PDFAntibiotic resistance has been becoming more and more critical due to bacteria's evolving hydrolysis enzymes. The NDM-1 enzyme could hydrolyze not only carbapenems but also most of β-lactam's antibiotics and inhibitors. In fact, variant strains could impose a high impact on the resistance of bacteria producing NDM-1.
View Article and Find Full Text PDFTraditional/herbal medicine has gained increasing interests recently, especially in Asian countries such as Vietnam, due to its diverse therapeutic actions. In the treasure of Vietnamese medicinal plants, one of the potential herbs is the roots of Ait. (SF, "Kho sam" in Vietnamese).
View Article and Find Full Text PDFIL(interleukin)-6 is a multifunctional cytokine crucial for immunological, hematopoiesis, inflammation, and bone metabolism. Strikingly, IL-6 has been shown to significantly contribute to the initiation of cytokine storm-an acute systemic inflammatory syndrome in Covid-19 patients. Recent study has showed that blocking the IL-6 signaling pathway with an anti-IL-6 receptor monoclonal antibody (mAb) can reduce the severity of COVID-19 symptoms and enhance patient survival.
View Article and Find Full Text PDFThe World Health Organization declared monkeypox a global public health emergency on 23 July 2022. This disease was caused by the monkeypox virus (MPXV), which was first identified in 1958 in Denmark. The MPXV is a member of the Poxviridae family, the Chordopoxvirinae subfamily, and the genus Orthopoxvirus, which share high similarities with the vaccinia virus (the virus used to produce the smallpox vaccine).
View Article and Find Full Text PDFUnlabelled: The main protease 3CL is one of the potential targets against coronavirus. Inhibiting this enzyme leads to the interruption of viral replication. Chalcone and its derivatives were reported to possess the ability to bind to 3CL protease in the binding pocket.
View Article and Find Full Text PDFBACKGROUND Foreign bodies (FBs) in the intra- or extra-peritoneal cavity are relatively rare. The aim of treatment is to remove the FB to prevent chronic inflammation and/or infection. Traditionally, surgical management is necessary, as the detection and localization of FBs can be difficult.
View Article and Find Full Text PDFRecent successes in Generative Adversarial Networks (GAN) have affirmed the importance of using more data in GAN training. Yet it is expensive to collect data in many domains such as medical applications. Data Augmentation (DA) has been applied in these applications.
View Article and Find Full Text PDFSeven new lignans, cleistonkinins A- E (1-5), cleistonkisides A and B (6-7) were isolated from the fruits of Cleistanthus tonkinensis (Euphorbiaceae), together with five known aryltetralin lignans, cleisindoside B (8), cleistantoxin (9), cleisindoside D (10), neocleistantoxin (11) and polygamain (12). Their structures were established from spectral analysis, including mass spectrometry and 2D-NMR. The absolute configurations of 4-7 were determined by analysis of their experimental CD spectra and comparison with calculated electronic circular dichroism (ECD) spectra.
View Article and Find Full Text PDFH1N1 is the earliest emerging subtype of influenza A viruses with available genomic sequences, has caused several pandemics and seasonal epidemics, resulting in millions of deaths and enormous economic losses. Timely determination of new antigenic variants is crucial for the vaccine selection and flu prevention. In this study, we chronologically divided the H1N1 strains into several periods in terms of the epidemics and pandemics.
View Article and Find Full Text PDFIEEE Trans Neural Syst Rehabil Eng
September 2018
Echolocation enables people with impaired or no vision to comprehend the surrounding spatial information through the reflected sound. However, this technique often requires substantial training, and the accuracy of echolocation is subject to various conditions. Furthermore, the individuals who practice this sensing method must simultaneously generate the sound and process the received audio information.
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