Ten cytochalasin derivatives, including six new methylthioether-containing chaetoglobosins (thiochaetoglobosins A-F, ), a new related congener (18-nor-prochaetoglobosin II, ), and three known unsulfured counterparts (), were isolated and identified from AS-506, an endozoic fungus isolated from a deep-sea sponge, which was collected from Magellan Seamounts in the Western Pacific Ocean. Their structures were determined by extensive interpretation of the spectroscopic and X-ray crystallographic data, as well as by ECD calculations. Structurally, thiochaetoglobosins A-F () represent the first examples of chaetoglobosin derivatives containing a methylthioether group in the molecules, while 18-nor-prochaetoglobosin II () is the first 18-nor-chaetoglobosin derivative.
View Article and Find Full Text PDFSumalarins D-G (1-4), four previously undescribed curvularin derivatives, along with two known related metabolites, curvularin (5) and dehydrocurvularin (6), were isolated and identified from the mangrove-derived fungus Penicillium sumatrense MA-325. Among them, sumalarin D (1) represents a unique example of curvularin derivative featuring a 5-methylfuran-2-yl-methyl group. Their structures were elucidated based on analysis of NMR and MS data as well as comparison of ECD spectra and quantum chemical calculations of NMR, and compound 1 was confirmed by X-ray crystallographic analysis.
View Article and Find Full Text PDFIntroducing an external visible-light field would be a promising strategy to improve the activity of the electrocatalytic CO reduction reaction (CORR), but it still remains a challenge due to the short excited-state lifetime of active sites. Herein, Ru(bpy)Cl struts as powerful photosensitive donors were immobilized into the backbones of Co-porphyrin-based covalent organic frameworks (named Co-Bpy-COF-Ru, is the molar ratio of Ru and Co species, = 1/2 and 2/3) via coordination bonds, for the photo-coupled CORR to produce CO. The optimal Co-Bpy-COF-Ru displays a high CO Faradaic efficiency of 96.
View Article and Find Full Text PDFWe propose an effective highest occupied d-orbital modulation strategy engendered by breaking the coordination symmetry of sites in the atomically precise Cu nanocluster (NC) to switch the product of CO electroreduction from HCOOH/CO to higher-valued hydrocarbons. An atomically well-defined Cu NC with symmetry-broken Cu-S N active sites (named Cu (MBD) , MBD=2-mercaptobenzimidazole) was designed and synthesized by a judicious choice of ligand containing both S and N coordination atoms. Different from the previously reported high HCOOH selectivity of Cu NCs with Cu-S sites, the Cu (MBD) with Cu-S N coordination structure shows a high Faradaic efficiency toward hydrocarbons of 65.
View Article and Find Full Text PDFFour new oxepine-containing pyrazinopyrimidine alkaloids, versicoxepines A - D (1-4), two quinolinone alkaloid analogs including 3-hydroxy-6-methoxy-4-phenylquinolin-2(1H)-one (5) and 3-methoxy-6-hydroxy-4-phenylquinolin-2(1H)-one (6) which were new naturally occurring compounds, together with two known compounds (7 and 8) were isolated from Aspergillus versicolor AS-212, an endozoic fungus isolated from the deep-sea coral Hemicorallium cf. imperiale, which was collected from the Magellan Seamounts in the Western Pacific Ocean. Their structures were determined by extensive analysis of the spectroscopic and X-ray crystallographic data as well as by chiral HPLC analysis, ECD calculation, and DP4+ probability prediction.
View Article and Find Full Text PDFTwo new quinazolinone diketopiperazine alkaloids, including versicomide E () and cottoquinazoline H (), together with ten known compounds (, , and -) were isolated and identified from AS-212, an endozoic fungus associated with the deep-sea coral cf. , which was collected from the Magellan Seamounts. Their chemical structures were determined by an extensive interpretation of the spectroscopic and X-ray crystallographic data as well as specific rotation calculation, ECD calculation, and comparison of their ECD spectra.
View Article and Find Full Text PDFWe present the first example of charged imidazolium functionalized porphyrin-based covalent organic framework (Co-iBFBim-COF-X) for electrocatalytic CO reduction reaction, where the free anions (e.g., F , Cl , Br , and I ) of imidazolium ions nearby the active Co sites can stabilize the key intermediate *COOH and inhibit hydrogen evolution reaction.
View Article and Find Full Text PDFObjectives: To compare the levels of serum pepsinogen (PG) in patients with gastric cancer (GC), patients with atrophic gastritis (AG), and healthy donors. Also, we explored the clinical value of PG detection for the diagnosis and treatment of GC.
Methods: The PG level in peripheral blood from patients and heathy donors was determined using an Abbott automatic chemiluminescence instrument.
Micro-arc oxidation (MAO) was used to improve the resistance of pure magnesium (Mg). Copper (Cu), a good antibacterial, angiogenic, and osteogenic element, was added by reaction in a Cu-containing electrolyte to improve the osteogenic and pro-angiogenic activities of Mg. The surface microstructures of the resulting MAO were evaluated by a scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS) mapping.
View Article and Find Full Text PDFObjectives: This study aimed to investigate the factors affecting the quantity of DNA and RNA extractable from human formalin-fixed paraffin-embedded (FFPE) tissues stored for different lengths of time.
Methods: We randomly selected 20 FFPE specimens harvested from hysteromyoma patients with uterine fibroids during 2010, 2015, and 2017 at the Department of Pathology, Jiading District Central Hospital Affiliated Shanghai University of Medicine and Health Sciences. DNA and RNA extractions were performed using a DNA/RNA FFPE kit.
Objectives: The purpose of this paper was to synthesize 4-amino-1,2,4-triazole Schiff base derivative and to evaluate its antitumor activity.
Methods: 2,4,6-Tris (4-formylphenoxy)-1,3,5-triazine was synthesized by nucleophilic substitution with reaction of -hydroxybenzaldehyde with cyanuric chloride. Then, the intermediate was reacted with 1,2,4-triazole to form 4-amino-1,2,4-triazole Schiff base derivative by reduction and ammonification of aldehydes.
During soil formation, the accumulation of humic substances such as humic acid and fulvic acid is an important way to maintain soil fertility and nutrient cycling, which is regulated by soil substrate quality, litter, and environmental factors. In a laboratory incubation experiment, we exa-mined the effects of litter addition on soil humic substances accumulation in freeze-thaw environment by controlling the freeze-thaw cycles and litter additions in soils from the typical coniferous forest, mixed forest and broadleaved forest in a subalpine forest in western Sichuan. The freeze-thaw events significantly increased the content of humic substances in the coniferous forest soils but decreased those in the mixed forest soil and broadleaved forest soil.
View Article and Find Full Text PDFChronic hepatitis B (CHB) is associated with the development of hepatocellular carcinoma (HCC). Decoy receptor 3 (DcR3) is a tumor necrosis factor receptor that promotes tumor cell survival by inhibiting apoptosis and interfering with immune surveillance. Previous studies showed that DcR3 was overexpressed in HCC cells and that short hairpin RNA (shDcR3) sensitizes TRAIL-resistant HCC cells.
View Article and Find Full Text PDFEvidence has shown that most hepatocellular carcinoma (HCC) cells are resistant to tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis. However, the molecular mechanisms underlying TRAIL-mediated apoptosis resistance are not well understood. In this study, we reported that downregulation of Decoy receptor 3 (DcR3) expression by lentiviral vectors carrying shRNA against DcR3 (LV-ShDcR3, shDcR3) in Huh7 both greatly enhanced TRAIL-mediated apoptosis and reduced cell proliferation capability.
View Article and Find Full Text PDFBackground: Ghrelin is a hormone that protects against hypoxic injury of cardiac cells by inducing autophagy, but the role of autophagy in sepsis remains unclear. This study aimed to evaluate whether ghrelin could enhance autophagy in rats with intestinal sepsis.
Methods: The cecal ligation and perforation (CLP) method was used to induce sepsis in Sprague-Dawley rats.
The urotensin II/urotensin receptor (UII/UT) system can mediate inflammatory liver injury in acute liver failure (ALF); however; the related mechanism is not clear. In this study, we confirmed that lipopolysaccharide/D-galactosamine (LPS/D-GalN) induced up-regulation of liver interferon regulatory factor 3 (IRF3) in ALF mice, whereas the UT antagonist urantide inhibited the up-regulated liver IRF3. LPS stimulation induced IRF3 transcription and nuclear translocation and promoted the secretion of interleukin-6 (IL-6), interferon (IFN)-β, and IFN-γ in Kupffer cells (KCs); these effects in LPS-stimulated KCs were inhibited by urantide.
View Article and Find Full Text PDFMicroRNAs (miRNAs or miRs) are small, non-coding RNA molecules that play significant roles in numerous diseases. However, there is limited information regarding the plasma expression of miRNAs in patients with primary biliary cirrhosis (PBC) as well as the potential role of miRNAs in the development of PBC. miRNA microarray analysis was performed using plasma obtaind from three patients with PBC and three healthy controls.
View Article and Find Full Text PDFCD36, a scavenger receptor, plays an important role in the progression of atherosclerosis through its interaction with oxidized low-density lipoprotein (ox-LDL). Porphyromonas gingivalis (P. gingivalis, Pg) has been shown to promote macrophage-derived foam cell formation by affecting the expression of CD36.
View Article and Find Full Text PDFCell-free circulating DNA (cf-DNA) can be detected by various of laboratory techniques. We described a branched DNA-based Alu assay for measuring cf-DNA in septic patients. Compared to healthy controls and systemic inflammatory response syndrome (SIRS) patients, serum cf-DNA levels were significantly higher in septic patients (1426.
View Article and Find Full Text PDFPurpose: Unbalanced inflammatory response and lymphocyte apoptosis is associated with high mortality in septic patients. Decoy receptor 3 (DcR3), a member of the tumor necrosis factor receptor superfamily, is an anti-inflammatory and anti-apoptotic factor. Recently, DcR3 expression was found to be increased in septic patients.
View Article and Find Full Text PDFWorld J Gastroenterol
March 2015
Aim: To investigate urotensin-II (UII) and its effects on tumor necrosis factor (TNF)-α and interleukin (IL)-1β in early acute liver failure (ALF).
Methods: We investigated the time-dependent alteration in UII levels and its effects on TNF-α and IL-1β in liver and blood in the early stage of lipopolysaccharide/D-galactosamine-induced ALF.
Results: After lipopolysaccharide/D-galactosamine challenge, UII rose very rapidly and reached a maximal level 0.
The urotensin II (UII)/UII receptor (UT) system is closely related to immune inflammation. In acute liver failure (ALF), the UII/UT system can promote the production and release of proinflammatory cytokines, inducing an inflammatory injury response in liver tissue. However, the mechanism by which the hepatic UII/UT system promotes proinflammatory cytokine production and release is not clear.
View Article and Find Full Text PDFChronic infection with hepatitis B virus (HBV) plays a significant role in hepatocellular carcinoma development. To investigate the effect of hepatitis B virus X protein (HBx) on inflammatory cytokines of human T cell, a eukaryotic expression vector, HBx-pEGFP-C1, was constructed and transfected into the Jurkat human T-cell line. Jurkat cells were transfected transiently using Lipofectamine 2000 and activated by phytohemagglutinin (PHA).
View Article and Find Full Text PDFUrotensin II (UII) is implicated in immune inflammatory diseases through its specific high-affinity UT receptor (UTR). Enhanced expression of UII/UTR was recently demonstrated in the liver with acute liver failure (ALF). Here, we analysed the relationship between UII/UTR expression and ALF in lipopolysaccharide (LPS)/D-galactosamine (GalN)-challenged mice.
View Article and Find Full Text PDFZhonghua Gan Zang Bing Za Zhi
September 2012
To investigate the mechanisms of serine/threonine kinase Pim-3 inhibition of fulminant hepatic apoptosis. Thirty-two rats were randomly divided into four groups (n = 8 each): normal controls (A); pretreatment with Ringer's solution (B), vector plasmid (C), or Pim-3 recombinant plasmid (D) by hydrodynamics-based procedure followed by intraperitoneal injections of lipopolysaccharide (LPS) and D-galactosamine (D-GalN) after one day. At 8 h after the LPS/D-GalN injections, liver tissues were collected from all groups of mice and analyzed for cell apoptosis by detecting caspase-3 activity (measured in relative fluorescence units, RFU).
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