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1.
Phys Chem Chem Phys ; 25(9): 6746-6756, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36807438

RESUMEN

Nanoscale thermal transport at solid-liquid interfaces plays an essential role in many engineering fields. This work performs deep potential molecular dynamics (DPMD) simulations to investigate thermal transport across copper-water interfaces. Unlike traditional classical molecular dynamics (CMD) simulations, we independently train a deep learning potential (DLP) based on density functional theory (DFT) calculations and demonstrated its high computational efficiency and accuracy. The trained DLP predicts radial distribution functions (RDFs), vibrational densities of states (VDOS), density curves, and thermal conductivity of water confined in the nanochannel at a DFT accuracy. The thermal conductivity decreases slightly with an increase in the channel height, while the influence of the cross-sectional area is negligible. Moreover, the predicted interfacial thermal conductance (ITC) across the copper-water interface by DPMD is 2.505 × 108 W m-2 K-1, the same order of magnitude as the CMD and experimental results but with a high computational accuracy. This work seeks to simulate the thermal transport properties of solid-liquid interfaces with DFT accuracy at large-system and long-time scales.

2.
Phys Chem Chem Phys ; 25(14): 10175-10183, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36976635

RESUMEN

The exfoliated two-dimensional (2D) Ga2O3 opens new avenues to fine-tune the carrier and thermal transport properties for improving the electro-thermal performance of gallium oxide-based power electronics with their enhanced surface-to-volume ratios and quantum confinement. Yet, the carrier transport in 2D Ga2O3 has not been fully explored, especially considering their large Fröhlich coupling constants. Herein, we mainly investigate the electron mobility of monolayer (ML) and bilayer (BL) Ga2O3 from first-principles by adding polar optical phonon (POP) scattering. The results show that POP scattering is the dominant factor limiting the electron mobility for 2D Ga2O3, accompanied by a large 'ion-clamped' dielectric constant Δε. The value of Δε is 3.77 and 4.60 for ML and BL Ga2O3, respectively, indicating a large change in polarization in the external field. The electron mobility of 2D Ga2O3 enhances with increasing thickness despite the enhanced electron-phonon coupling strength and Fröhlich coupling constant. The predicted electron mobility for BL and ML Ga2O3 at a carrier concentration of 1.0 × 1012 cm-2 is 125.77 cm2 V-1 s-1 and 68.30 cm2 V-1 s-1 at room temperature, respectively. This work aims to unravel the scattering mechanisms beneath engineering electron mobility of 2D Ga2O3 for promising applications in high-power devices.

3.
J Am Chem Soc ; 143(37): 15011-15016, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34516737

RESUMEN

The synthesis of three-dimensional (3D) covalent organic frameworks (COFs) requires high-connectivity polyhedral building blocks or the controlled alignment of building blocks. Here, we use the latter strategy to assemble square-planar cobalt(II) phthalocyanine (PcCo) units into the nbo topology by using tetrahedral spiroborate (SPB) linkages that were chosen to provide the necessary 90° dihedral angles between neighboring PcCo units. This yields a porous 3D COF, SPB-COF-DBA, with a noninterpenetrated nbo topology. SPB-COF-DBA shows high crystallinity and long-range order, with 11 resolved diffraction peaks in the experimental powder X-ray diffraction (PXRD) pattern. This well-ordered crystal lattice can also be imaged by using high-resolution transmission electron microscopy (HR-TEM). SPB-COF-DBA has cubic pores and exhibits permanent porosity with a Brunauer-Emmett-Teller (BET) surface area of 1726 m2 g-1.

4.
J Environ Manage ; 255: 109859, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32063319

RESUMEN

China's paper industry development is rapid, but the recycling rate of China's waste paper has been low all the time. Meanwhile, material flow analysis can help determine the flow of waste paper, and life cycle assessment (LCA) is the methodological framework for quantifying greenhouse gas emissions. Therefore, present study integrates these two methods into the model construction of China's waste paper recycling decision system. Present study constructs a benchmark model of China's waste paper recycling decision system in 2017, focusing on the impact of nonstandard waste paper recycling on the economic and environmental benefits of China's domestic waste paper recycling system. This model construction is followed by sensitivity analysis of the relevant parameters affecting the efficiency of the waste paper recycling system. Finally, present study forecasts the system's economic benefits and greenhouse gas (GHG) emissions in the context of integrating and regulating nonstandard recycling vendors. The results show that the economic benefit of China's waste paper recycling in 2017 is approximately 458.3 yuan/t and that the GHG emissions are 901.1 kgCO2eq. The standard recovery rate and nonstandard recovery acceptance rate will both have a significant impact on the system's economic benefits and improve the GHG emissions structure. In the context of integrating nonstandard recycling enterprises and individual recycling vendors, the economic benefits will rise to 3312.5 yuan/t in 2030, while GHG emissions will rise to 942.9 kgCO2eq. Present study can play a certain guiding role for policy makers in formulating waste paper recycling industry specifications and formulating relevant policies.


Asunto(s)
Gases de Efecto Invernadero , Reciclaje , China , Efecto Invernadero , Industrias
5.
Xenobiotica ; 49(10): 1158-1163, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30484368

RESUMEN

Parthenolide (PTL) and micheliolide (MCL) are sesquiterpene lactones with similar structures, and both of them have been reported to exhibit multiple biochemical and pharmacological activities. This study aims to investigate the inhibition of these two compounds on the activity of UDP-glucuronosyltransferases (UGTs). In vitro incubation mixture for recombinant UGTs-catalyzed glucuronidation metabolism of 4-methylumbelliferone (4-MU) was utilized to investigate the inhibition potential. Inhibition kinetics (including inhibition type and parameters) were determined, and in silico docking was employed to elucidate the inhibition difference between PTL and MCL on UGT1A1. MCL showed no inhibition toward all the UGT isoforms, and PTL showed strong inhibition toward UGT1A1. The half-maximal inhibitory concentration (IC50) of PTL on the activity of UGT1A1 was determined to be 64.4 µM. Inhibition kinetics determination showed that PTL exerted noncompetitive inhibition toward UGT1A1, and the inhibition kinetic constant (Ki) was determined to be 12.1 µM. In silico docking method has been employed to show that hydrogen bonds between PTL and the activity cavity of UGT1A1 contributed to the stronger inhibition of PTL on the activity of UGT1A1 than MCL. In conclusion, PTL can more easily induce drug-drug interaction (DDI) with clinical drugs mainly undergoing UGT1A1-catalyzed glucuronidation.


Asunto(s)
Inhibidores Enzimáticos , Glucuronosiltransferasa/antagonistas & inhibidores , Glucuronosiltransferasa/química , Sesquiterpenos de Guayano , Sesquiterpenos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Humanos , Cinética , Sesquiterpenos/química , Sesquiterpenos/farmacocinética , Sesquiterpenos/farmacología , Sesquiterpenos de Guayano/química , Sesquiterpenos de Guayano/farmacocinética , Sesquiterpenos de Guayano/farmacología
6.
Xenobiotica ; 48(3): 250-257, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28285550

RESUMEN

1. UDP-glucuronosyltransferases (UGTs) are important drug-metabolizing enzymes (DMEs) catalyzing the glucuronidation elimination of various xenobiotics and endogenous substances. Endogenous substances are important regulators for the activity of various UGT isoforms. Triiodothyronine (T3) and thyroxine (T4) are important thyroid hormones essential for normal cellular differentiation and growth. The present study aims to elucidate the inhibition behavior of T3 and T4 on the activity of UGT isoforms. 2. In vitro recombinant UGTs-catalyzed glucuronidation of 4-methylumbelliferone (4-MU) was used to screen the inhibition potential of T3 and T4 on the activity of various UGT isoforms. Initial screening results showed that T4 exerted stronger inhibition potential than T3 on the activity of various UGT isoforms at 100 µM. Inhibition kinetics was determined for the inhibition of T4 on the representative UGT isoforms, including UGT1A1, -1A3, -1A7, -1A8, -1A10 and -2B7. The results showed that T4 competitively inhibited the activity of UGT1A1, -1A3, -1A7, 1A10 and -2B7, and noncompetitively inhibited the activity of UGT1A8. The inhibition kinetic parameters were calculated to be 1.5, 2.4, 11, 9.6, 4.8 and 3.0 µM for UGT1A1, -1A3, -1A7, -1A8, -1A10 and -2B7, respectively. In silico docking method was employed to demonstrate why T4 exerted stronger inhibition than T3 towards UGT1A1. Stronger hydrogen bonds and hydrophobic interaction between T4 and activity cavity of UGT1A1 than T3 contributed to stronger inhibition of T4 towards UGT1A1. 3. In conclusion, more clinical monitoring should be given for the patients with the elevation of T4 level due to stronger inhibition of UGT isoforms-catalyzed metabolism of drugs or endogenous substances by T4.


Asunto(s)
Glucuronosiltransferasa/antagonistas & inhibidores , Tiroxina/farmacología , Triyodotironina/farmacología , Inhibidores Enzimáticos/farmacología , Glucuronosiltransferasa/química , Glucuronosiltransferasa/metabolismo , Humanos , Enlace de Hidrógeno , Himecromona/metabolismo , Simulación del Acoplamiento Molecular , Tiroxina/química , Triyodotironina/química
7.
Am J Physiol Cell Physiol ; 313(5): C567-C574, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28814403

RESUMEN

Oxidized low-density lipoprotein (oxLDL) accumulates early in atherosclerotic lesions and plays an important role in the progressive formation of atherosclerotic plaques. Endothelial derived microparticles (EMPs) form a heterogeneous population of <1-µm particles that shed from endothelial membranes upon activation. While EMPs are shown to be involved in atherosclerotic pathophysiology and progression, there is no report regarding the relationship between oxLDL and EMPs. In this study, we aim to determine the influence of oxLDL on endothelial microparticle release and the subsequent regulation of the endothelial activation. EMPs were collected from the medium of human umbilical vein endothelial cells (HUVECs) treated with oxLDL or PBS as control. We find that oxLDL increases the release of EMPs containing intercellular adhesion molecule 1 (ICAM-1) but not vascular cell adhesion molecule 1 (VCAM-1). Confocal microscopy analysis further demonstrates that these EMPs interact with endothelial cells and increase the expression of ICAM-1 in HUVECs. The fact that injecting oxLDL-induced EMPs via the tail vein of ICR mice augments ICAM-1 expression on aortic endothelial cells confirms our results in vivo. Finally, oxLDL-induced EMPs from HUVECs increase the adhesion of monocytes to endothelial cells as determined by the adhesion assay. Our study suggests that oxLDL may augment the release of EMPs harboring increased levels of ICAM-1 that can be transferred to endothelial cells elsewhere. This leads to increased monocyte recruitment in other regions where oxLDL accumulation was initially more limited. EMPs may therefore serve as the mediator that propagates oxLDL-induced endothelial inflammation.


Asunto(s)
Micropartículas Derivadas de Células/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Molécula 1 de Adhesión Intercelular/biosíntesis , Lipoproteínas LDL/farmacología , Monocitos/metabolismo , Animales , Aterosclerosis/metabolismo , Adhesión Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Ratones Endogámicos ICR , Monocitos/efectos de los fármacos
8.
Xenobiotica ; 47(5): 376-381, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27359323

RESUMEN

1. The exposed level of vitamin A in plasma might be exceeded due to the both inadvertent and clinical utilization. The adverse effects of vitamin A have been frequently reported, however, the mechanism remains unclear. The inhibition of vitamin A on the activity of UDP-glucuronosyltransferases (UGTs) was determined using in vitro incubation system to explain the adverse effects of vitamin A from a new perspective. 2. UGT supersomes catalyzed glucuronidation of 4-methylumbelliferone (4-MU), trifluoperazine (TFP), and cotinine was used as the probe reaction to evaluate the inhibition of vitamin A toward UGT isoforms, and 100 µM of vitamin A significantly inhibited the activity of all the tested UGT isoforms. Vitamin A exerted competitive inhibition on the activity of UGT1A1, 2B4, 2B7, and 2B15, and the inhibition kinetic parameters (Ki) were calculated to be 31.1, 16.8, 2.2, and 11.6 µM for UGT1A1, 2B4, 2B7, and 2B15. In silico docking method was used to try to elucidate the inhibition mechanism of vitamin A toward UGT2B7. The results showed the significant contribution of hydrogen bonds and hydrophobic interaction on the UGT2B7 inhibition by vitamin A. 3. The present study provides a new perspective for the adverse effects of vitamin A through reporting the inhibition of vitamin A on the activity of important phase II drug-metabolizing enzymes UGTs, which benefits our deep understanding of mechanism of vitamin A's adverse effects when high exposure of vitamin A occurs.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Glucuronosiltransferasa/metabolismo , Vitamina A/farmacología , Inhibidores Enzimáticos/metabolismo , Himecromona , Cinética , Vitamina A/metabolismo
9.
Arch Toxicol ; 91(5): 2235-2244, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27853831

RESUMEN

Alpha-naphthyl isothiocyanate (ANIT)-induced liver damage is regarded as a useful model to study drug-induced cholestatic hepatitis. Ultra-performance liquid chromatography coupled with electrospray ionization quadrupole mass spectrometry (UPLC-ESI-QTOF MS)-based metabolomics revealed clues to the mechanism of ANIT-induced liver injury, which facilitates the elucidation of drug-induced liver toxicity. 1-Stearoyl-2-hydroxy-sn-glycero-3-phosphocholine (LPC 18:0) and 1-oleoyl-2-hydroxy-sn-glycero-3-phosphocholine (LPC 18:1) were significantly increased in serum from ANIT-treated mice, and this increase resulted from altered expression of genes encoding the lipid metabolism enzymes Chka and Scd1. ANIT also increased NF-κB/IL-6/STAT3 signaling, and in vitro luciferase reporter gene assays revealed that LPC 18:0 and LPC 18:1 can activate NF-κB in a concentration-dependent manner. Activation of PPARα through feeding mice a Wy-14,643-containing diet (0.1%) reduced ANIT-induced liver injury, as indicated by lowered ALT and AST levels, and liver histology. In conclusion, the present study demonstrated a role for the lipid-regulated NF-κB/IL-6/STAT3 axis in ANIT-induced hepatotoxicity, and that PPARα may be a potential therapeutic target for the prevention of drug-induced cholestatic liver injury.


Asunto(s)
1-Naftilisotiocianato/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Interleucina-6/metabolismo , FN-kappa B/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Modelos Animales de Enfermedad , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Ratones Endogámicos C57BL , Ratones Mutantes , PPAR alfa/genética , PPAR alfa/metabolismo , Pirimidinas/farmacología
10.
Molecules ; 22(6)2017 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-28621744

RESUMEN

Mangiferin (MGF), the predominant constituent of extracts of the mango plant Mangifera Indica L., has been investigated extensively because of its remarkable pharmacological effects. In vitro recombinant UGTs-catalyzed glucuronidation of 4-methylumbelliferone (4-MU) was used to investigate the inhibition of mangiferin and aglycone norathyriol towards various isoforms of UGTs in our study, which evaluated the inhibitory capacity of MGF and its aglycone norathyriol (NTR) towards UDP-glucuronosyltransferase (UGT) isoforms. Initial screening experiment showed that deglycosylation of MGF into NTR strongly increased the inhibitory effects towards almost all the tested UGT isoforms at a concentration of 100 µM. Kinetic experiments were performed to further characterize the inhibition of UGT1A3, UGT1A7 and UGT1A9 by NTR. NTR competitively inhibited UGT1A3, UGT1A7 and UGT1A9, with an IC50 value of 8.2, 4.4, and 12.3 µM, and a Ki value of 1.6, 2.0, and 2.8 µM, respectively. In silico docking showed that only NTR could dock into the activity cavity of UGT1A3, UGT1A7 and UGT1A9. The binding free energy of NTR to UGT1A3, 1A7, 1A9 were -7.4, -7.9 and -4.0 kcal/mol, respectively. Based on the inhibition evaluation standard ([I]/Ki < 0.1, low possibility; 0.1 < [I]/Ki < 1, medium possibility; [I]/Ki > 1, high possibility), an in vivo herb-drug interaction between MGF/NTR and drugs mainly undergoing UGT1A3-, UGT1A7- or UGT1A9-catalyzed metabolism might occur when the plasma concentration of NTR is above 1.6, 2.0 and 2.8 µM, respectively.


Asunto(s)
Glucuronosiltransferasa/metabolismo , Isoenzimas/metabolismo , Xantonas/química , Glucuronosiltransferasa/antagonistas & inhibidores , Interacciones de Hierba-Droga , Isoenzimas/antagonistas & inhibidores , Xantenos/química
11.
Yao Xue Xue Bao ; 52(1): 66-70, 2017 01.
Artículo en Zh | MEDLINE | ID: mdl-29911771

RESUMEN

Praeruptorin C (PC), D (PD) and E (PE) are important compounds extracted from Peucedanum praeruptorum DUNN and have been reported to exert multiple pharmacological activities. The present study is purposed to determine the inhibition of PC, PD and PE on the activity of important phase I metabolic enzymes ­ carboxylesterases (CES). In vitro human liver microsomes (HLM) incubation system was used to determine the inhibition potential of PC, PD and PE on the activity of CES1 and CES2. Inhibition behaviour was determined, and in vitro-in vivo extrapolation was performed by using the combination of in vitro inhibition kinetic parameter (K(I)) and in vivo exposure level of PD. PD exhibited the strongest inhibition on the activity of CES1, with 81.7% activity inhibited by 100 µmol·L(-1) of PD. PD noncompetitively inhibited the activity of CES1 with the K(I) to be 122.2 µmol·L(-1), indicating inhibition potential of PD towards CES1 in vivo. Therefore, closely monitoring the endogenous metabolic disorders caused by PD and interaction between PD and drugs mainly undergoing CES1-catalyzed metabolism is very necessary.


Asunto(s)
Carboxilesterasa/antagonistas & inhibidores , Hidrolasas de Éster Carboxílico/antagonistas & inhibidores , Cumarinas/farmacología , Apiaceae/química , Humanos , Cinética , Microsomas Hepáticos
12.
Xenobiotica ; 46(6): 503-10, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26560012

RESUMEN

1. Fructus psoraleae (FP) is the dried ripe seeds of Psoralea corylifolia L. (Fabaceae) widely used in Asia, and has been reported to exert important biochemical and pharmacological activities. The adverse effects of FP remain unclear. The present study aims to determine the inhibition of human carboxylesterase 1 (CES1) by FP's major ingredients, including neobavaisoflavone, corylifolinin, coryfolin, psoralidin, corylin and bavachinin. 2. The probe substrate of CES1 2-(2-benzoyl-3-methoxyphenyl) benzothiazole (BMBT) was derived from 2-(2-hydroxy-3-methoxyphenyl) benzothiazole (HMBT), and human liver microsomes (HLMs)-catalyzed BMBT metabolism was used to phenotype the activity of CES1. In silico docking method was employed to explain the inhibition mechanism. 3. All the tested compounds exerted strong inhibition towards the activity of CES1 in a concentration-dependent behavior. Furthermore, the inhibition kinetics was determined for the inhibition of neobavaisoflavone, corylifolinin, coryfolin, corylin and bavachinin towards CES1. Both Dixon and Lineweaver-Burk plots showed that neobavaisoflavone, corylifolinin, coryfolin and corylin noncompetitively inhibited the activity of CES1, and bavachinin competitively inhibited the activity of CES1. The inhibition kinetic parameters (Ki) were calculated to be 5.3, 9.4, 1.9, 0.7 and 0.5 µM for neobavaisoflavone, corylifolinin, coryfolin, corylin and bavachinin, respectively. In conclusion, the inhibition behavior of CES1 by the FP's constituents was given in this article, indicating the possible adverse effects of FP through the disrupting CES1-catalyzed metabolism of endogenous substances and xenobiotics.


Asunto(s)
Hidrolasas de Éster Carboxílico/antagonistas & inhibidores , Extractos Vegetales/farmacología , Psoralea/química , Fabaceae , Flavonoides/farmacología , Humanos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Simulación del Acoplamiento Molecular , Extractos Vegetales/química
13.
Phytother Res ; 30(11): 1872-1878, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27534594

RESUMEN

Praeruptorin A (PA) and B (PB) are two important compounds isolated from Bai-hua Qian-hu and have been reported to exert multiple biochemical and pharmacological activities. The present study aims to determine the inhibition of PA and PB on the activity of important phase II drug-metabolizing enzymes uridine 5'-diphospho-glucuronosyltransferase (UGTs) isoforms. In vitro UGT incubation system was used to determine the inhibition potential of PA and PB on the activity of various UGT isoforms. In silico docking was performed to explain the inhibition difference between PA and PB towards the activity of UGT1A6. Inhibition behaviour was determined, and in vitro-in vivo extrapolation was performed by using the combination of in vitro inhibition kinetic parameter (Ki ) and in vivo exposure level of PA. Praeruptorin A (100 µM) exhibited the strongest inhibition on the activity of UGT1A6 and UGT2B7, with 97.8% and 90.1% activity inhibited by 100 µM of PA, respectively. In silico docking study indicates the significant contribution of hydrogen bond interaction towards the stronger inhibition of PA than PB towards UGT1A6. Praeruptorin A noncompetitively inhibited the activity of UGT1A6 and competitively inhibited the activity of UGT2B7. The inhibition kinetic parameter (Ki ) of PA towards UGT1A6 and UGT2B7 was calculated to be 1.2 and 3.3 µM, respectively. The [I]/Ki value was calculated to be 15.8 and 5.8 for the inhibition of PA on UGT1A6 and UGT2B7, indicating high inhibition potential of PA towards these two UGT isoforms in vivo. Therefore, closely monitoring the interaction between PA and drugs mainly undergoing UGT1A6 or UGT2B7-catalyzed metabolism is very necessary. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Cumarinas/química , Glucuronosiltransferasa/antagonistas & inhibidores , Isoformas de Proteínas/metabolismo , Cumarinas/farmacología , Humanos
14.
Molecules ; 21(12)2016 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-27916843

RESUMEN

As one of the main active ingredients from Radix Astragali (RA), orally dosed astragaloside IV (AST) is easily transformed to sapogenin-cycloastragenol (CAG) by deglycosylation in the gastrointestinal tract. Because the potential adverse effects of AST and CAG remain unclear, the present study in this article was carried out to investigate the inhibition effects of AST and CAG on UDP-glucuronosyltransferases (UGTs) to explore potential clinical toxicity. An in vitro UGTs incubation mixture was employed to study the inhibition of AST and CAG towards UGT isoforms. Concentrations of 100 µM for each compound were used to initially screen the inhibitory efficiency. Deglycosylation of AST to CAG could strongly increase the inhibitory effects towards almost all of the tested UGT isoforms, with an IC50 of 0.84 µM and 11.28 µM for UGT1A8 and UGT2B7, respectively. Ulteriorly, the inhibition type and kinetics of CAG towards UGT1A8 and UGT2B7 were evaluated depending on the initial screening results. Data fitting using Dixon and Lineweaver-Burk plots demonstrated that CAG competitively inhibited UGT1A8 and noncompetitively inhibited UGT2B7. From the second plot drawn with the slopes from the Lineweaver-Burk plot versus the concentrations of CAG, the inhibition constant (Ki) was calculated to be 0.034 µM and 20.98 µM for the inhibition of UGT1A8 and UGT2B7, respectively. Based on the [I]/Ki standard ([I]/Ki < 0.1, low possibility; 1 > [I]/Ki > 0.1, medium possibility; [I]/Ki > 1, high possibility), it was successfully predicted here that an in vivo herb-drug interaction between AST/CAG and drugs mainly undergoing UGT1A8- or UGT2B7-catalyzed metabolism might occur when the plasma concentration of CAG is above 0.034 µM and 20.98 µM, respectively.


Asunto(s)
Glucuronosiltransferasa/antagonistas & inhibidores , Sapogeninas/farmacología , Sapogeninas/farmacocinética , Saponinas/farmacología , Saponinas/farmacocinética , Triterpenos/farmacología , Triterpenos/farmacocinética , Medicamentos Herbarios Chinos , Interacciones de Hierba-Droga , Isoformas de Proteínas/antagonistas & inhibidores
15.
Cardiovasc Diabetol ; 13: 82, 2014 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-24751283

RESUMEN

BACKGROUND: Glycation of high-density lipoprotein (HDL) decreases its ability to induce cyclooxygenase-2 (COX-2) expression and prostacyclin I-2 (PGI-2) release in endothelial cells. Whether lipid content of HDL, especially sphingosine-1-phosphate (S1P), plays any specific role in restoring the protective function of HDL in type 2 diabetes mellitus (T2DM) is still unknown. METHODS AND RESULTS: Immunochemical techniques demonstrated that glycated HDL loses its protective function of regulating COX-2 expression compared with diabetic HDL. We proved that the lipid content, especially phospholipid content differed between diabetic HDL and glycated HDL. Levels of HDL-c-bound S1P were increased in T2DM compared with control subjects as detected by UPLC-MS/MS (HDL-c-bound S1P in control subjects vs. T2DM: 309.1 ± 13.71 pmol/mg vs. 382.1 ± 24.45 pmol/mg, P < 0.05). Additionally, mRNA levels of S1P lyase enzymes and S1P phosphatase 1/2 were decreased in peripheral blood by real-time PCR. Antagonist of S1P receptor 1 and 3 (S1PR1/3) diminished the functional difference between apoHDL&PL (HDL containing the protein components and phospholipids) and diabetic apoHDL&PL (diabetic HDL containing the protein components and phospholipids). With different doses of S1P reconstituted on glycated HDL, its function in inducing the COX-2 expression was restored to the same level as diabetic HDL. The mechanism of S1P reconstituted HDL (rHDL) in the process of regulating COX-2 expression involved the phosphorylation of ERK/MAPK-CREB signal pathway. CONCLUSION/SIGNIFICANCE: S1P harbored on HDL is the main factor which restores its protective function in endothelial cells in T2DM. S1P and its receptors are potential therapeutic targets in ameliorating the vascular dysfunction in T2DM.


Asunto(s)
Citoprotección/fisiología , Diabetes Mellitus Tipo 2/sangre , Glicosilación , Lipoproteínas HDL/sangre , Lisofosfolípidos/sangre , Esfingosina/análogos & derivados , Células Cultivadas , Diabetes Mellitus Tipo 2/patología , Diabetes Mellitus Tipo 2/prevención & control , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Esfingosina/sangre
16.
Int J Mol Sci ; 15(5): 8846-62, 2014 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-24857916

RESUMEN

Transgene copy number has a great impact on the expression level and stability of exogenous gene in transgenic plants. Proper selection of endogenous reference genes is necessary for detection of genetic components in genetically modification (GM) crops by quantitative real-time PCR (qPCR) or by qualitative PCR approach, especially in sugarcane with polyploid and aneuploid genomic structure. qPCR technique has been widely accepted as an accurate, time-saving method on determination of copy numbers in transgenic plants and on detection of genetically modified plants to meet the regulatory and legislative requirement. In this study, to find a suitable endogenous reference gene and its real-time PCR assay for sugarcane (Saccharum spp. hybrids) DNA content quantification, we evaluated a set of potential "single copy" genes including P4H, APRT, ENOL, CYC, TST and PRR, through qualitative PCR and absolute quantitative PCR. Based on copy number comparisons among different sugarcane genotypes, including five S. officinarum, one S. spontaneum and two S. spp. hybrids, these endogenous genes fell into three groups: ENOL-3--high copy number group, TST-1 and PRR-1--medium copy number group, P4H-1, APRT-2 and CYC-2--low copy number group. Among these tested genes, P4H, APRT and CYC were the most stable, while ENOL and TST were the least stable across different sugarcane genotypes. Therefore, three primer pairs of P4H-3, APRT-2 and CYC-2 were then selected as the suitable reference gene primer pairs for sugarcane. The test of multi-target reference genes revealed that the APRT gene was a specific amplicon, suggesting this gene is the most suitable to be used as an endogenous reference target for sugarcane DNA content quantification. These results should be helpful for establishing accurate and reliable qualitative and quantitative PCR analysis of GM sugarcane.


Asunto(s)
ADN de Plantas/análisis , Dosificación de Gen , Reacción en Cadena en Tiempo Real de la Polimerasa , Saccharum/genética , ADN de Plantas/normas , Genoma de Planta , Hojas de la Planta/genética , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Especificidad de la Especie , Transgenes
17.
Int J Mol Sci ; 15(2): 2738-60, 2014 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-24552874

RESUMEN

Chitinases (EC 3.2.2.14), expressed during the plant-pathogen interaction, are associated with plant defense against pathogens. In the present study, a positive correlation between chitinase activity and sugarcane smut resistance was found. ScChi (GenBank accession no. KF664180), a Class III chitinase gene, encoded a 31.37 kDa polypeptide, was cloned and identified. Subcellular localization revealed ScChi targeting to the nucleus, cytoplasm and the plasma membrane. Real-time quantitative PCR (RT-qPCR) results showed that ScChi was highly expressed in leaf and stem epidermal tissues. The ScChi transcript was both higher and maintained longer in the resistance cultivar during challenge with Sporisorium scitamineum. The ScChi also showed an obvious induction of transcription after treatment with SA (salicylic acid), H2O2, MeJA (methyl jasmonate), ABA (abscisic acid), NaCl, CuCl2, PEG (polyethylene glycol) and low temperature (4 °C). The expression levels of ScChi and six immunity associated marker genes were upregulated by the transient overexpression of ScChi. Besides, histochemical assay of Nicotiana benthamiana leaves overexpressing pCAMBIA 1301-ScChi exhibited deep DAB (3,3'-diaminobenzidinesolution) staining color and high conductivity, indicating the high level of H2O2 accumulation. These results suggest a close relationship between the expression of ScChi and plant immunity. In conclusion, the positive responses of ScChi to the biotic and abiotic stimuli reveal that this gene is a stress-related gene of sugarcane.


Asunto(s)
Quitinasas/metabolismo , Saccharum/enzimología , Estrés Fisiológico , Secuencia de Bases , Quitinasas/clasificación , Quitinasas/genética , Peróxido de Hidrógeno/metabolismo , Datos de Secuencia Molecular , Filogenia , Hojas de la Planta/metabolismo , Hojas de la Planta/microbiología , Proteínas de Plantas , Estructura Terciaria de Proteína , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Saccharum/microbiología , Temperatura , Nicotiana/metabolismo , Regulación hacia Arriba , Ustilaginales/patogenicidad
18.
Int J Biol Macromol ; 257(Pt 2): 128757, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38092123

RESUMEN

Hydrogels from natural polymers are eco-friendly, biocompatible and adjustable for manufacturing wearable sensors. However, it is still challenging to prepare natural polymer hydrogel sensors with excellent properties (e.g., high conductivity). Here, we developed a physically cross-linked, highly conductive and multifunctional hydrogel (named PPTP) to address this challenge. The natural renewable pectin-based PPTP hydrogel is synthesized by introducing tannic acid (TA), calcium chloride (CaCl2), and sodium chloride (NaCl) into the pectin/polyvinyl alcohol (PVA) dual network structure. The hydrogel exhibits excellent characteristics, including unique tensile strength (2.6155 MPa), high electrical conductivity (7 S m-1), and high sensitivity (GF = 3.75). It is also recyclable, further enhancing its eco-friendly nature. The PPTP hydrogel can be used for monitoring human joint activities, as flexible electrodes for monitoring electrocardiogram (ECG) signals, and touchable screen pen for electronic skin. Moreover, when combined with Morse code and wireless Bluetooth technology, PPTP hydrogels can be used for underwater and land information encryption, and decryption. Our unique PPTP hydrogel offers promising opportunities for medical monitoring, information transfer, and human-computer interaction.


Asunto(s)
Hidrogeles , Pectinas , Polifenoles , Humanos , Polisacáridos , Conductividad Eléctrica , Polímeros , Cloruro de Sodio
19.
Nanomicro Lett ; 16(1): 69, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38175419

RESUMEN

The development of bioinspired gradient hydrogels with self-sensing actuated capabilities for remote interaction with soft-hard robots remains a challenging endeavor. Here, we propose a novel multifunctional self-sensing actuated gradient hydrogel that combines ultrafast actuation and high sensitivity for remote interaction with robotic hand. The gradient network structure, achieved through a wettability difference method involving the rapid precipitation of MoO2 nanosheets, introduces hydrophilic disparities between two sides within hydrogel. This distinctive approach bestows the hydrogel with ultrafast thermo-responsive actuation (21° s-1) and enhanced photothermal efficiency (increase by 3.7 °C s-1 under 808 nm near-infrared). Moreover, the local cross-linking of sodium alginate with Ca2+ endows the hydrogel with programmable deformability and information display capabilities. Additionally, the hydrogel exhibits high sensitivity (gauge factor 3.94 within a wide strain range of 600%), fast response times (140 ms) and good cycling stability. Leveraging these exceptional properties, we incorporate the hydrogel into various soft actuators, including soft gripper, artificial iris, and bioinspired jellyfish, as well as wearable electronics capable of precise human motion and physiological signal detection. Furthermore, through the synergistic combination of remarkable actuation and sensitivity, we realize a self-sensing touch bioinspired tongue. Notably, by employing quantitative analysis of actuation-sensing, we realize remote interaction between soft-hard robot via the Internet of Things. The multifunctional self-sensing actuated gradient hydrogel presented in this study provides a new insight for advanced somatosensory materials, self-feedback intelligent soft robots and human-machine interactions.

20.
ACS Appl Mater Interfaces ; 15(13): 16631-16639, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36943938

RESUMEN

In order to selectively oxidize benzyl alcohol, a novel noble metal catalyst based on polymer ionic liquids with a core-shell structure was created. First, polymer ionic liquid microspheres (PILMs) were prepared by free radical polymerization. Second, the in situ adsorption of Au nanoparticles on the surface of PILMs was accomplished, thanks to the strong electrostatic interaction between N atoms and metal ions on the diazole ring of PILMs. Additionally, the introduction of Al(OH)3 prevented the aggregation of Au nanoparticles and promoted the catalytic reaction. Finally, the PILM/Au/Al(OH)3 catalyst with a core-shell structure was formed. The effectiveness of the PILM/Au/Al(OH)3 catalyst was assessed by varying the catalyst's type, quantity, amount of Au, amount of H2O2, temperature, and reaction time. After five cycles of experiments, the catalyst was effective and reusable. In addition, the potential catalytic mechanism of the catalyst in the oxidation of benzyl alcohol was proposed.

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