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Herein, a hydroxyl‑riched covalent organic framework (named COF-DES-1) was synthesized using 1,3,5-tris(4-aminophenyl)benzene and 2,5-dihydroxyterephthalaldehyde as building blocks and employed as a coating of solid-phase microextraction (SPME) fiber. Ascribed to the advantages (e.g. suitable pore size and rich functional group characteristics) of coating, the SPME fiber showed good adsorption capacities to flavonoids aglycones including luteolin and quercetagetin, and the maximum adsorption capacities for them were 145.31 µg and 84.75 µg, respectively. Due to the size exclusion property of COF-DES-1, SPME fiber showed good protein exclusion effects on seven selected proteins with high exclusion efficiencies (93%). Accordingly, an attractive strategy of the combination of COF-DES-1 based SPME fiber and HPLC-MS/MS was proposed for the extraction and determination of luteolin, quercetagetin or their metabolites. The results revealed that the fiber can be effectively applied to extract luteolin and its metabolites, and quercetagetin from mice's palsma. Compared with the traditional protein precipitation methods, the extraction effects of SPME fiber based extraction method were much better, indicating the promising applicability of the fiber for the enrichment of flavonoids aglycones or their metabolites in biological samples.

Oil red O was applied as precursor to synthesize nitrogen-doped carbon dots (NCDs) by a facile solvothermal method for the first time. Surprisingly, liquid–liquid extraction and purification resulted in the quantum yield (QY) of NCDs up to 68%. The purification mechanism is based on the difference in polarity and solubility between precursor, over-carbonized substances and NCDs. Further, optical properties and structure characterizations of NCDs were characterized by ultraviolet (UV) spectroscopy, fluorescence (FL) spectroscopy, transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). Importantly, NCDs can be acted as an outstanding multi-functional sensing platform for Cu2+ and tetracycline antibiotics (TCs). Compared with other coexisting metal ions and antibiotics, this platform showed special responses to Cu2+ and TCs. NCDs showed high selectivity and sensitivity of fluorescence response to Cu2+ over a broad range of 10 nM −50 μM and a satisfactory detection limit (LOD)of 4 nM. Besides, NCDs also showed high sensitivity for the detection of TCs with a LOD range of 50 pM-100 nM. In addition, the fluorescent quenching mechanism of Cu2+ and TCs to NCDs were identified as IFE and static quenching. Finally, the platform was successful applied to detect Cu2+ and TCs in actual samples (e.g., water, milk, urine) with satisfactory results. All results indicated that NCDs appeared to have tremendous potential for Cu2+ and TCs detection in various fields.

In this study, an eco-friendly extraction method that used tailor-made deep eutectic solvents (DESs) for the extraction of oxymatrine and matrine from Sophora flavescens Aiton root was implemented for the first time. The extraction parameters, including the DES type, DES water content, solid-to-liquid ratio, extraction time, and extraction temperature, which affected the extraction efficiencies of oxymatrine and matrine were optimised. High-performance liquid chromatography with a diode-array detector and quantitative analysis of the DES components was conducted. The highest oxymatrine and matrine extraction yields (21.04 and 1.53 mg·g−1, respectively) were obtained using DES-2 (comprising choline chloride and malonic acid; molar ratio of 1:2) with 50% water and DES-8 (comprising choline chloride and ethylene glycol; molar ratio of 1:2) with 30% water as the extraction solvents, respectively. Furthermore, magnetic molecularly imprinted polymers (MMIPs) were successfully synthesised using oxymatrine, acrylic acid, ethylene glycol dimethylacrylate, azobisisobutyronitrile, and acetonitrile–methylbenzene (3:1, v/v) as the template, functional monomer, cross-linker, initiator, and porogen, respectively. The MMIPs were characterised using transmission electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction analyses, and the results demonstrated the successful preparation of MMIPs. The adsorption properties of MMIPs were further analysed using static and dynamic adsorption experiments, and the results indicated that MMIPs presented good adsorption capacities for oxymatrine and matrine (110.8 and 63.4 mg·g−1, respectively). Lastly, MMIPs were used as sorbents for the extraction and enrichment of oxymatrine and matrine from DES extracts of S. flavescens roots. The extraction efficiencies of oxymatrine and matrine (80.21–89.15% and 85.33–95.28%, respectively) were satisfactory. The proposed DES-based extraction followed by MMIPs secondary enrichment appeared to be an effective method for the selective extraction of specific components from complex samples.

Platelet activation plays a crucial role in hemostasis and thrombosis. Thrombin, the most potent stimulus of platelet activation, mediates platelet activation via the protease activated receptors (PARs). The platelet PAR repertoire in mediating thrombin's action differs across species. Only nonhuman primate (NHP) platelet activation is known to be similar to humans, mediated by PAR1 and PAR4, hence limiting translational in vivo studies of PAR's role in thrombosis and hemostasis to NHPs. Earlier studies have demonstrated a range of distinct in vitro activities of PAR1 and 4 in platelet activation yet the implications of these events in vivo is unclear. The objective of this study is to investigate and compare the roles of PAR1 and PAR4 in hemostasis and thrombosis in a relevant animal species. NHP models for pharmacokinetic, ex vivo platelet aggregation responses, FeCI3 injury-mediated arterial thrombosis and template bleeding were developed in Cynomolgus Macaques. Potent and selective small molecule antagonists of PAR1 and PAR4 were characterized in an array of in vitro assays, and subsequently examined head-to-head in the NHP models. Treatment of NHPs with antagonists of PAR1 or PAR4 both resulted in strong inhibition of ex vivo platelet aggregation. At doses that led to similar inhibition of platelet aggregation, animals treated with the PAR4 antagonist showed similar levels of anti-thrombotic efficacy, but longer bleeding times, compared to animals treated with the PAR1 antagonist. These findings suggest that PAR1 antagonism will likely produce a larger therapeutic index (ie. a larger anti-thrombotic efficacy over bleeding risk margin) than PAR4 antagonism.

Vorapaxar is a novel protease-activated receptor-1 (PAR-1) antagonist recently approved for the reduction of thrombotic cardiovascular events in patients with a history of myocardial infarction or with peripheral arterial disease. Patients who received vorapaxar in addition to standard of care antiplatelet therapy had an increased incidence of major bleeding events compared with placebo. To assess whether platelet transfusion can restore hemostasis in primates on triple antiplatelet therapy, template bleeding times were assessed concurrently in the buccal mucosa, finger pad, and distolateral tail of anesthetized cynomolgus macaques to evaluate bleeding with vorapaxar as either monotherapy or in combination with aspirin or aspirin and clopidogrel. Aspirin (5mg/kg, IV) or vorapaxar (1mg/kg, PO) alone had no significant effect on bleeding times in the three vascular beds examined. A modest (

Fibrosis, or the accumulation of extracellular matrix, causes loss of organ function and is a common feature of many chronic diseases. To interrogate the core molecular pathways of fibrosis, we cross-examined human primary cells from various tissues treated with TGFβ. Transcriptome analyses revealed that in addition to the known TGFβ signature, top-regulated cluster of genes are involved in fatty acid metabolism. To further evaluate this observation in vivo, we characterized a renal fibrosis model through unilateral ureteral obstruction (UUO) in mice. TGFβ signaling was greatly augmented in UUO kidneys and preventive treatment with an anti-TGFβ antibody resulted in significant reduction of fibrosis. Transcriptome analysis also identified fatty acid metabolism as one of the top dysregulated pathways in UUO kidneys, which was further supported by a substantial accumulation of acylcarnitines. Additional rodent models of liver fibrosis revealed a similar metabolic signature upon fibrosis induction. Lastly, a compound library phenotypic screen for suppressers of fibrosis identified AMPK and PPAR activators. As a proof of concept, we demonstrated that pharmacological treatment of telmisartan, an angiotensin receptor and PPARγ dual-agent, significantly reduced fibrosis in UUO kidneys, suggesting that metabolic defect is integral to TGFβ signaling and fibrosis. Altogether, our work has revealed a common node of metabolic signature underlying fibrosis that could represent a promising therapeutic target for multiple fibrotic diseases.

Introduction In vivo profiles of aldosterone synthase inhibitors (ASIs) have been investigated utilizing various rodent models. Due to lack of CYP17 activity, rodents produce corticosterone rather than cortisol as that of humans, which raised concern to their effectiveness in translational pharmacological characterization of ASI. Methods A rhesus monkey model that combines a low sodium diet with adrenocorticotropin (ACTH) treatment was developed. Plasma concentrations of steroid metabolites associated with reactions catalyzed by CYP11B2 and CYP11B1 were measured concurrently by a UPLC/MS method. Results Plasma concentration of aldosterone in regular diet fed rhesus monkeys was low at 109 pg/mL. Aldosterone concentrations were increased to 252 pg/mL when animals were maintained on a low sodium diet for 3 weeks, and to 300 pg/mL with ACTH treatment at 0.3 mg/kg. The combination of low sodium diet with ACTH treatment further increased plasma concentration of aldosterone to 730 pg/mL and other steroid metabolites at various levels. Intravenous administration of ASI, fadrozole (0.001–1 mg/kg) or LCI699 (0.003–3 mg/kg), led to dose-dependent reductions in aldosterone and 18-hydroxycorticosterone, increases in 11-deoxycorticosterone and 11-deoxycortisol, and bell-shaped changes in cortisol and corticosterone. In vivo selectivity of CYP11B2/CYP11B1 for fadrazole was 26-fold and LCI-699 was 27-fold, which was consistent with relative selectivity using in vitro values from recombinant cells transfected with rhesus monkey CYP11B2 and CYP11B1. Discussion This model enables concurrent characterization of pharmacokinetics, pharmacodynamics and selectivity of CYP11B2 over CYP11B1 inhibition in the same animal. It may be used as a translational model for pharmacological characterization of ASI.

Microstructure and mechanical properties of AZ61 Mg alloy during isothermal multi-axial forging (MAF) were studied. The mechanisms of grain refinement and relationship between the microstructures and mechanical properties were discussed. The results show that the average grain size decreases with increasing the number of MAF passes. The grains are significantly refined at the lst and 2nd MAF passes, and gradually refined at higher MAF passes. The initial grain size of 148 μm decreases to about 14 μm after 6 MAF passes. The grain refinement occurs mainly by continuous dynamic recrystallization. With increasing the MAF passes, both the tensile strength and the elongation to failure of the alloy are significantly enhanced.

Long chain L-2-hydroxy acid oxidase 2 (Hao2) is a peroxisomal enzyme expressed in the kidney and the liver. Hao2 was identified as a candidate gene for blood pressure (BP) quantitative trait locus (QTL) but the identity of its physiological substrate and its role in vivo remains largely unknown. To define a pharmacological role of this gene product, we report the development of selective inhibitors of Hao2. We identified pyrazole carboxylic acid hits 1 and 2 from screening of a compound library. Lead optimization of these hits led to the discovery of 15-XV and 15-XXXII as potent and selective inhibitors of rat Hao2. This report details the structure activity relationship of the pyrazole carboxylic acids as specific inhibitors of Hao2.

GPR91, a 7TM G-Protein-Coupled Receptor, has been recently deorphanized with succinic acid as its endogenous ligand. Current literature indicates that GPR91 plays role in various pathophysiology including renal hypertension, autoimmune disease and retinal angiogenesis. Starting from a small molecule high-throughput screening hit 1 (hGPR91 IC(50): 0.8 μM)-originally synthesized in Merck for Bradykinin B(1) Receptor (BK(1)R) program, systematic structure-activity relationship study led us to discover potent and selective hGPR91 antagonists e.g. 2c, 4c, and 5 g (IC(50): 7-35 nM; >1000 fold selective against hGPR99, a closest related GPCR; >100 fold selective in Drug Matrix screening). This initial work also led to identification of two structurally distinct and orally bio-available lead compounds: 5g (%F: 26) and 7e (IC(50): 180 nM; >100 fold selective against hGPR99; %F: 87). A rat pharmacodynamic assay was developed to characterize the antagonists in vivo using succinate induced increase in blood pressure. Using two representative antagonists, 2c and 4c, the GPR91 target engagement was subsequently demonstrated using the designed pharmacodynamic assay.

The incidence of cholesterol gallstones is a very common disease. The aim of this study is to probe for underlying intestinal molecular defects associated with development of gallstones. Twelve Chinese patients with cholesterol gallstone disease (GS) and 31 gallstone-free (GSF) patients were investigated. Quantitation of mRNA levels for individual genes in mucosal biopsies from jejunum was carried out with real-time PCR. The frequency of two SNPs in the ABCG8 gene (Y54C and T400K) was determined by allelic discrimination. The intestinal mRNA expression of NPC1L1 and ACAT2 were significantly higher in GS than GSF (P0.05). No differences were observed concerning the levels for plasma lipids, plant sterols and 7alpha-hydroxy-4-cholesten-3-one between GS and GSF. No correlations were observed between patients carrying the different genotypes for Y54C or T400K and their mRNA levels for ABCG5 or ABCG8. The increased NPC1L1 and ACAT2 mRNA levels in gallstone patients might indicate an upregulated absorption and esterification of cholesterol in the small intestine.

Heavy exercise or oxygen deficit often links with higher levels of arterial lactate and lower levels of plasma free fatty acids (FFA). Treatment with lactate reduces circulating levels of FFA in vivo and lipolysis in adipose tissues in vitro. However, the underlying mechanism has remained unclear. Here we employ pharmacological and genetic approaches to show that GPR81, an orphan G-protein-coupled receptor with relatively restricted expression in the adipose tissues, functions as a receptor for lactate and can mediate an anti-lipolytic effect of lactate. GPR81 may thus function as a sensor of lactate that can modulate the FFA pool under exercise or conditions of oxygen deficit.

We present a Judd–Ofelt spectroscopic analysis on the Mg/Er-codoped congruent lithium niobate (LiNbO 3 ) crystals. The Judd–Ofelt model is applied to the room temperature unpolarized absorption intensities of Er 3+ ions on eleven transition bands to determine their intensity parameters: Ω 2 =2.36×10 −20 cm 2 , Ω 4 =0.76×10 −20 cm 2 , Ω 6 =0.30×10 −20 cm 2 in Er:LiNbO 3 crystal heavily codoped with MgO. The radiative lifetime of 2 H 9/2 becomes longer when MgO is added into Er:LiNbO 3 crystal. The experimental lifetimes are obtained using microsecond time-resolved spectra at 400 nm femtosecond pulse excitation to predict radiative quantum efficiency. Combining higher radiative quantum efficiency with longer radiative lifetime, we conclude that Mg/Er-codoped LiNbO 3 crystals are more suitable than Er: LiNbO 3 ones in laser materials.

Nicotinic acid is a commonly used anti-dyslipidemic agent that increases plasma levels of HDL-cholesterol and decrease triglycerides (TG), and VLDL- and LDL-cholesterol. The most well-studied effect of nicotinic acid is its ability to lower plasma free fatty acids, which has been observed in humans and many animal models. However, its ability to raise HDL in humans has not been replicated in animal models, which precludes studying the mechanism of HDL elevation. Here we studied lipid-modulating effects of nicotinic acid in mice carrying genomic DNA fragments that drive expression of various human genes in the mouse liver. Treatment with nicotinic acid reduced serum levels of HDL cholesterol in wild-type and human apolipoprotein B100 (apoB100)-transgenic mice. In contrast, nicotinic acid treatment of mice that express human cholesteryl ester transfer protein (CETP), with or without concomitant apoB100 expression, resulted in a significant increase of HDL cholesterol and reduction of TG, VLDL- and LDL-cholesterol. These data demonstrate a critical role of CETP in nicotinic acid-mediated HDL elevation, and suggest that mice carrying the human CETP gene may be useful animal models for studying the HDL-elevating effect of nicotinic acid.

Objective This study was conducted to assess the rapid diagnosis of fungal infections in patients with acute necrotizing pancreatitis by polymerase chain reaction (PCR) using universal primers targeting the 18S rRNA gene. Methods In this study, a PCR assay was developed to identify clinically isolated fungi, and both PCR technique and conventional culture were used to detect fungi in 37 samples from patients with acute necrotizing pancreatitis. Results A 197-bp fragment was amplified by PCR from all the clinically isolated fungal strains. This fragment was not isolated from gram-positive, gram-negative bacteria or human leucocytes. Thirty-seven samples of necrotic tissue or peripancreatic fluid from 11 patients were also analyzed, and eight samples were positive for fungi by PCR, six of which were also positive by conventional culture. The whole PCR procedure was completed within 7 hours. Conclusion PCR can be used to diagnose fungal infection secondary to acute necrotizing pancreatitis rapidly and sensitively. ( Asian J Surg 2002;25(3):209-13)

Cell adhesion mediated by leukocyte integrin CR3 (CD11b/CD18, alpha m beta 2) may be rapidly modulated without changes in receptor number, and transient changes in adhesivity are thought to be driven by reversible alteration of the affinity of CR3 for ligand. Here we measure the binding affinity of CR3 using purified active and inactive receptor and the ligand, C3bi, coupled to alkaline phosphatase. Immobilized, active CR3 bound saturably and with high affinity (12.5 +/- 4.7 nM). In contrast, inactive CR3 exhibited no measurable binding. High affinity binding could be restored by the addition of the activating anti-CR3 monoclonal antibody KIM-127 to inactive CR3. Since the affinity of KIM-127 for active and inactive receptor was identical, it cannot contribute the energy to convert a low affinity receptor into a high affinity receptor. Rather, KIM-127 appears to facilitate binding of C3bi by lowering the activation energy for the shift from an inactive to an active state. These results suggest that CR3-mediated binding and detachment of cells is not driven by a reversible change in affinity but by two mechanistically distinct processes, an energetically neutral activation step for binding and an energy-dependent step that reverses binding of ligand.

A pile group consisted of in-plane hinge-jointed, rigid, sloping piles embedded in a homogeneous, isotropic elastic half space under in-plane loading is analysed by Line-Loaded Integral Equation Method (LLIEM). Based on the analysis of a single pile, where the problem is reduced to a set of Fredholm integral equations of the first kind and solved numerically by LLIEM, the analysis of a pile group consisted of two hinge-jointed, rigid, sloping piles under in-plane loading at a joint is reduced to a set of 10 simultaneous nonlinear equations with 10 unknowns and solved by group iteration method. A program is designed for the solution of this problem. The accuracy of the numerical solution can be checked by the reciprocal theorem of work.

This paper presents the analysis of a shaft by the line-loaded integral equation method. The shaft is considered to be an elastic cylindrical shell, with constant or step-varied thickness, with or without hinged supports, embedded in a granular half space under the action of gravity. The problem is reduced to a Fredholm integral equation of the first kind and its numerical result is given.

The lanthanide chloride complexes with the ligand N,N,N′,N′-tetraphenyl-3,6-dioxaoctanedioic diamide (TDD) have been prepared in an ethanol-chloroform solution. These new complexes with general formula [Ln(TDD)Cl2(H2O)2]Cl(Ln = La, Pr, Nd, Sm-Er) have been characterized by elemental analysis, conductivity measurements, IR spectra, f-f electronic spectra, 1H NMR spectra and TG-DTA techniques. In all the complexes, the ligand TDD shows quadridentate behaviour.

The fundamental growth thermograms of Bacillus sp. NTT-61 have been determined by the microcalorimetric method. From these thermograms we calculate the multiplication rate constant K a and activation energy E a A formula for bacterial growth is given as where X is the bacterium, S the substrate, (X·S) the bacterium-substrate complex, P the product, and K a the rate constant. This pattern is similar to the transition state pattern in chemistry, so according to the transition state theory of reaction dynamics we can calculate the activation entropy (Δ S ≠ ) and activation free enthalpy (Δ G ne ) of bacterial growth processes. These are very useful data with which to study bacterial thermodynamic properties.