Background: With metabolic dysfunction-associated fatty liver disease (MAFLD) incidence and prevalence increasing, it is necessary to identify patients with advanced fibrosis (F3-F4 stages). We evaluated the performance of new biomarkers and algorithms for diagnosing advanced fibrosis in an Asian population.
Methods: Data from two Asian cohorts (including 851 biopsy-proven MAFLD [578 from Wenzhou, 273 from Hong Kong]) were studied.
Based on the structural characteristics of aztreonam (AZN) and its target PBP3, a series of new monobactam derivatives bearing various substituents on oxime residue were prepared and evaluated for their antibacterial activities against susceptible and resistant Gram-negative bacteria. Among them, compounds 8p and 8r displayed moderate potency with MIC values of 0.125-32 μg/mL against most tested Gram-negative strains, comparable to AZN.
View Article and Find Full Text PDFAn unprecedented and efficient [4 + 3] cycloaddition of N-(ortho-chloromethyl)aryl amides with nitrones has been developed. This approach provides easy access to a series of seven-membered benzooxadiazepine derivatives in good to excellent yields (up to 99% yield) under mild reaction conditions.
View Article and Find Full Text PDFPreventing filoviruses in the entry stage is an attractive antiviral strategy. Taking aloperine, a Chinese natural herb with an endocyclic skeleton, as the lead, 23 new aloperine derivatives were synthesized and evaluated for their anti-filovirus activities including ebola virus (EBOV) and marburg virus (MARV) using pseudotyped virus model. Structure-activity relationship (SAR) analysis indicated that the introduction of a 12N-dichlorobenzyl group was beneficial for the potency.
View Article and Find Full Text PDFIn this paper, we explored the protective effect and physiochemical mechanism of He-Ne laser preillumination in enhancement of tall fescue seedlings tolerance to high salt stress. The results showed that salt stress greatly reduced plant growth, plant height, biomass, leaf development, ascorbate acid (AsA) and glutathione (GSH) concentration, the enzymatic activities, and gene expression levels of antioxidant enzymes such as catalase (CAT) and glutathione reductase (GR) and enhanced hydrogen peroxide (H2O2) content, superoxide radical (O2 (·-)) generation rates, membrane lipid peroxidation, relative electrolyte leakage, the enzymatic activities, and gene expression levels of superoxide dismutase (SOD), ascorbate peroxidase (APX), and peroxidase (POD), compared with controls. However, He-Ne laser preillumination significantly reversed plant growth retardation, biomass loss, and leaves development decay induced by salt stress.
View Article and Find Full Text PDFA series of novel N-substituted sophocarpinic acid derivatives was designed, synthesized, and evaluated for their anti-enteroviral activities against coxsackievirus type B3 (CVB3) and coxsackievirus type B6 (CVB6) in Vero cells. Structure-activity relationship analysis revealed that the introduction of a benzenesulfonyl moiety on the 12-nitrogen atom in (E)-β,γ-sophocarpinic acid might significantly enhance anti-CVB3 activity. Among the derivatives, (E)-12-N-(m-cyanobenzenesulfonyl)-β,γ-sophocarpinic acid (11 m), possessing a meta-cyanobenzenesulfonyl group, exhibited potent activity against CVB3 with a selectivity index (SI) of 107.
View Article and Find Full Text PDFBackground: The emergence of multi-drug resistant tuberculosis (MDR-TB) has heightened the need for new chemical classes and innovative strategies to tackle TB infections. It is urgent to discover new classes of molecules without cross-resistance with currently used antimycobacterial drugs.
Results: Eighteen new 8-substituted protoberberine derivatives were synthesized and evaluated for their anti-mycobacterial activities against Mycobacterium tuberculosis (M.
Twenty-eight new 13-n-octylberberine derivatives were synthesized and evaluated for their activities against drug-susceptible Mycobacterium tuberculosis (M. tuberculosis) strain H(37)Rv. Among these compounds, compound 16e was the most effective anti-tubercular agent with a MIC value of 0.
View Article and Find Full Text PDFCurrently, there is no approved antiviral drug for the infection caused by enteroviruses. A series of novel N-arylethyl isoquinoline derivatives defined with substituents on the ring A and C were designed, synthesized and evaluated in vitro for their activities against Coxsackievirus B3 (CVB3). The primary structure-activity relationship revealed that substituents on the ring A were not beneficial for the activity.
View Article and Find Full Text PDFOxymatrine (1) is a natural anti-hepatitis B virus (HBV) drug that down-regulates host heat-stress cognate 70 (Hsc70) expression through a mechanism different from that of nucleosides. Taking Hsc70 as a target against HBV, 26 novel N-substituted matrinic acid analogs were designed, synthesized and evaluated for their regulation of Hsc70 mRNA expression with 1 as the lead. The SAR analysis revealed that (i) the carboxyl group at the 11-position was required for activity; (ii) introducing of a substituent on the nitrogen atom at the 12-position of 3, especially substituted benzyl, might significantly improve the activity.
View Article and Find Full Text PDFTen pharmacophore models of beta-tubulin inhibitors were established from the training set of seventeen beta-tubulin inhibitors (two categories) with comformer analysis by using the Catalyst software. The optimal pharmacophore model with two hydrophobic units and two hydrogen bond acceptor units were confirmed (RMS = 0.43, Correl = 0.
View Article and Find Full Text PDFHeat-stress cognate 70 (Hsc70) is a host protein required for hepatitis B virus (HBV) replication, and oxymatrine (1) suppresses Hsc70 expression. Taking Hsc70 as a target against HBV, 22 analogues of 1 defined with substituents at position 1, 13, or 14 were synthesized and evaluated for their activity on Hsc70 mRNA expression. The SAR revealed that (i) the oxygen atom at the 1-position was not essential, (ii) increasing electron density on the ring D reduced the activity, and (iii) introducing a proper substituent at the 13- and/or 14-position(s), especially electron-withdrawing groups, might enhance the activity.
View Article and Find Full Text PDFUnlabelled: Host heat shock cognate 70 (Hsc70) protein is packaged into hepatitis C viral (HCV) particles as a structural component of the virus in the assembly process. It helps HCV RNA release into the cytoplasm in the next infection cycle. The goal of this study is to investigate whether chemically down-regulating host Hsc70 expression could be a novel strategy to interrupt HCV replication.
View Article and Find Full Text PDFTwenty-nine derivatives of berberine (1) or pseudoberberine (2) were designed, semisynthesized, and evaluated for their up-regulatory activity on the low-density-lipoprotein receptor (LDLR) expression. SAR analysis revealed that (i) the methylenedioxy group at the 2- and 3-position is an essential element to keep the activity, (ii) the 7-position quaternary ammonium and planar structure of the compound are activity-required, and (iii) addition of electron-donating groups at the 7- or 13-position reduced the activity. Of the compound 1 analogues, compound 2 exhibited an increased activity on LDLR expression compared to 1.
View Article and Find Full Text PDFBerberine (BBR, 1) is a novel cholesterol-lowering agent that up-regulates low-density-lipoprotein receptor (LDLR) expression through a mechanism different from that of statins. Because of the unique mode of action and good safety record, BBR provoked our interest to do structure modification at different domains for its cholesterol-lowering activity. Nineteen BBR analogues with substituents on the benzene ring D were synthesized in the present study.
View Article and Find Full Text PDFForty-six new compounds were synthesized on the basis of our knowledge of the 3-haloacylamino benzoylurea (HBU) series. Structure-activity relationship (SAR) analysis indicates that (i) the configuration of the chiral center in 1 (JIMB01) is not indispensable for the activity, (ii) the phenyl ring is essential, and (iii) a substitution at the 6-position of the phenyl ring with a halogen enhances the activity. Among the analogues, 11e and 14b bearing 6-fluoro substitution showed potent activities against nine human tumor cell lines, including CEM (leukemia), Daudi (lymphoma), MCF-7 (breast cancer), Bel-7402 (hepatoma), DU-145 (prostate cancer), PC-3 (prostate cancer), DND-1A(melanoma), LOVO (colon cancer), and MIA Paca (pancreatic cancer) with IC 50 values between 0.
View Article and Find Full Text PDFYao Xue Xue Bao
December 2005
Aim: To design and synthesize new compounds of prandial glucose regulator with more simple structure.
Methods: The target compounds were synthesized from diethyl succinate and benzaldehyde or 4-fluorobenzaldehyde by four-step reactions. Thus 18 compounds were synthesized.
Sheng Wu Gong Cheng Xue Bao
January 2004
Direct DNA delivery procedures (include biolistics method) often resulted in multiple copies of the transgenes in transformants and certain copies of them were rearranged. Integration of multiple copies of the introduced genes was the main reason of gene silencing which meant inhibition or loss of foreign gene expression in filial generations of transformants. In the present work, we compared the influences of maize Ubi-1 promoter and other promoters on copy number of transgenes in maize transgenic plants.
View Article and Find Full Text PDF