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1.
Small Methods ; : e2301229, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528393

RESUMEN

The charge-transfer (CT) interactions between organic compounds are reflected in the (opto)electronic properties. Determining and visualizing crystal structures of CT complexes are essential for the design of functional materials with desirable properties. Complexes of pyranine (PYR), methyl viologen (MV), and their derivatives are the most studied water-based CT complexes. Nevertheless, very few crystal structures of CT complexes have been reported so far. In this study, the structures of two PYRs-MVs CT crystals and a map of the noncovalent interactions using 3D electron diffraction (3DED) are reported. Physical properties, e.g., band structure, conductivity, and electronic spectra of the CT complexes and their crystals are investigated and compared with a range of methods, including solid and liquid state spectroscopies and highly accurate quantum chemical calculations based on density functional theory (DFT). The combination of 3DED, spectroscopy, and DFT calculation can provide important insight into the structure-property relationship of crystalline CT materials, especially for submicrometer-sized crystals.

2.
Adv Sci (Weinh) ; 11(5): e2305099, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38044310

RESUMEN

2D transition metal carbides and nitrides (MXenes) suggest an uncommonly broad combination of important functionalities amongst 2D materials. Nevertheless, MXene suffers from facile oxidation and colloidal instability upon conventional water-based processing, thus limiting applicability. By experiments and theory, It is suggested that for stability and dispersibility, it is critical to select uncommonly high permittivity solvents such as N-methylformamide (NMF) and formamide (FA) (εr  = 171, 109), unlike the classical solvents characterized by high dipole moment and polarity index. They also allow high MXene stacking order within thin films on carbon nanotube (CNT) substrates, showing very high Terahertz (THz) shielding effectiveness (SE) of 40-60 dB at 0.3-1.6 THz in spite of the film thinness < 2 µm. The stacking order and mesoscopic porosity turn relevant for THz-shielding as characterized by small-angle X-ray scattering (SAXS). The mechanistic understanding of stability and structural order allows guidance for generic MXene applications, in particular in telecommunication, and more generally processing of 2D materials.

3.
BMC Genom Data ; 24(1): 67, 2023 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-37968621

RESUMEN

BACKGROUND: In 2022, a global outbreak of monkeypox occurred with a significant shift in its epidemiological characteristics. The monkeypox virus (MPXV) belongs to the B.1 lineage, and its genomic variations that were linked to the outbreak were investigated in this study. Previous studies have suggested that viral genomic variation plays a crucial role in the pathogenicity and transmissibility of viruses. Therefore, understanding the genomic variation of MPXV is crucial for controlling future outbreaks. METHODS: This study employed bioinformatics and phylogenetic approaches to evaluate the key genomic variation in the B.1 lineage of MPXV. A total of 979 MPXV strains were screened, and 212 representative strains were analyzed to identify specific substitutions in the viral genome. Reference sequences were constructed for each of the 10 lineages based on the most common nucleotide at each site. A total of 49 substitutions were identified, with 23 non-synonymous substitutions. Class I variants, which had significant effects on protein conformation likely to affect viral characteristics, were classified among the non-synonymous substitutions. RESULTS: The phylogenetic analysis revealed 10 relatively monophyletic branches. The study identified 49 substitutions specific to the B.1 lineage, with 23 non-synonymous substitutions that were classified into Class I, II, and III variants. The Class I variants were likely responsible for the observed changes in the characteristics of circulating MPXV in 2022. These key mutations, particularly Class I variants, played a crucial role in the pathogenicity and transmissibility of MPXV. CONCLUSION: This study provides an understanding of the genomic variation of MPXV in the B.1 lineage linked to the recent outbreak of monkeypox. The identification of key mutations, particularly Class I variants, sheds light on the molecular mechanisms underlying the observed changes in the characteristics of circulating MPXV. Further studies can focus on functional domains affected by these mutations, enabling the development of effective control strategies against future monkeypox outbreaks.


Asunto(s)
Monkeypox virus , Mpox , Humanos , Monkeypox virus/genética , Mpox/epidemiología , Filogenia , Brotes de Enfermedades , Genómica
4.
Environ Pollut ; 331(Pt 2): 121842, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37225075

RESUMEN

The construction of noise maps is of great significance for the management and control of urban noise and the protection of residents' physical and mental health. The European Noise Directive recommends using computational methods to construct strategic noise maps when possible. The current noise maps based on model calculation rely on complex noise emission and propagation models, and their huge number of regional grids needs to consume a lot of calculation time. This seriously restricts the update efficiency of noise maps, making it difficult to realize large-scale application and real-time dynamic update of noise maps. In order to improve the computational efficiency of noise maps, based on big data-driven technology, this paper combines the traditional CNOSSOS-EU noise emission modeling method with the multivariate nonlinear regression modeling method, and proposes an efficient calculation method of large-region dynamic traffic noise maps based on hybrid modeling method. First, this paper constructs the (daily and nightly) noise contribution prediction models of road sources with different classes, considering the daily and nightly periods and different urban road classes. Parameters of the proposed model are evaluated by using the multivariate nonlinear regression method to replace the complex nonlinear acoustic mechanism modeling. On this basis, in order to further improve the computational efficiency, noise contribution attenuations of the constructed models are parameterized and evaluated quantitatively. And then, the database containing the index table of the road noise sources-receivers and the corresponding noise contribution attenuations is constructed. The experimental results show that compared with the traditional calculation methods based on acoustic mechanism model, the noise map calculation method based on hybrid model proposed in this paper greatly reduces the model computations of noise map, improves the efficiency of noise mapping. It will provide technical support for constructing dynamic noise maps of large urban regions.


Asunto(s)
Ruido del Transporte , Acústica , Bases de Datos Factuales
5.
ACS Appl Mater Interfaces ; 15(5): 7063-7073, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36694305

RESUMEN

Cost-effective and high-performance H2S sensors are required for human health and environmental monitoring. 2D transition-metal carbides and nitrides (MXenes) are appealing candidates for gas sensing due to good conductivity and abundant surface functional groups but have been studied primarily for detecting NH3 and VOCs, with generally positive responses that are not highly selective to the target gases. Here, we report on a negative response of pristine Ti3C2Tx thin films for H2S gas sensing (in contrast to the other tested gases) and further optimization of the sensor performance using a composite of Ti3C2Tx flakes and conjugated polymers (poly[3,6-diamino-10-methylacridinium chloride-co-3,6-diaminoacridine-squaraine], PDS-Cl) with polar charged nitrogen. The composite, preserving the high selectivity of pristine Ti3C2Tx, exhibits an H2S sensing response of 2% at 5 ppm (a thirtyfold sensing enhancement) and a low limit of detection of 500 ppb. In addition, our density functional theory calculations indicate that the mixture of MXene surface functional groups needs to be taken into account to describe the sensing mechanism and the selectivity of the sensor in agreement with the experimental results. Thus, this report extends the application range of MXene-based composites to H2S sensors and deepens the understanding of their gas sensing mechanisms.

6.
Pharmacol Res ; 185: 106490, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36216131

RESUMEN

Acquired drug resistance and epithelial-mesenchymal transition (EMT) mediated metastasis are two highly interacting determinants for non-small-cell lung cancer (NSCLC) prognosis. This study investigated the common mechanisms of drug resistance and EMT from the perspective of metabolic reprogramming, which may offer new ideas to improve anticancer therapy. Acquired resistant cells were found to grow faster and have a greater migratory and invasive capacity than their parent cells. Metabolomics analysis revealed that acquired resistant cells highly relied on glutamine utilization and mainly fluxed into oxidative phosphorylation energy production. Further mechanistic studies screened out glutamate dehydrogenase 1 (GLUD1) as the determinant of glutamine addiction in acquired resistant NSCLC cells, and provided evidence that GLUD1-mediated α-KG production and the accompanying reactive oxygen species (ROS) accumulation primarily triggered migration and invasion by inducing Snail. Pharmacological and genetic interference with GLUD1 in vitro significantly reversed drug resistance and decreased cell migration and invasion capability. Lastly, the successful application of R162, a selective GLUD1 inhibitor, to overcome both acquired resistance and EMT-induced metastasis in vivo, identified GLUD1 as a promising and druggable therapeutic target for malignant progression of NSCLC. Collectively, our study offers a potential strategy for NSCLC therapy, especially for drug-resistant patients with highly expressed GLUD1.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Transición Epitelial-Mesenquimal , Glutamato Deshidrogenasa/genética , Glutamato Deshidrogenasa/uso terapéutico , Glutamina/metabolismo , Glutamina/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Factores de Transcripción de la Familia Snail/metabolismo
7.
Front Pharmacol ; 13: 932934, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36105197

RESUMEN

Tenofovir (TFV) ester prodrugs, a class of nucleotide analogs (NAs), are the first-line clinical anti-hepatitis B virus (HBV) drugs with potent antiviral efficacy, low resistance rate and high safety. In this work, three marketed TFV ester drugs, tenofovir disoproxil fumarate (TDF), tenofovir alafenamide fumarate (TAF) and tenofovir amibufenamide fumarate (TMF), were used as probes to investigate the relationships among prodrug structures, pharmacokinetic characteristics, metabolic activations, pharmacological responses and to reveal the key factors of TFV ester prodrug design. The results indicated that TMF and TAF exhibited significantly stronger inhibition of HBV DNA replication than did TDF in HBV-positive HepG2.2.15 cells. The anti-HBV activity of TMF was slightly stronger than TAF after 9 days of treatment (EC50 7.29 ± 0.71 nM vs. 12.17 ± 0.56 nM). Similar results were observed in the HBV decline period post drug administration to the HBV transgenic mouse model, although these three TFV prodrugs finally achieved the same anti-HBV effect after 42 days treatments. Furthermore, TFV ester prodrugs showed a correcting effect on disordered host hepatic biochemical metabolism, including TCA cycle, glycolysis, pentose phosphate pathway, purine/pyrimidine metabolism, amino acid metabolism, ketone body metabolism and phospholipid metabolism. The callback effects of the three TFV ester prodrugs were ranked as TMF > TAF > TDF. These advantages of TMF were believed to be attributed to its greater bioavailability in preclinical animals (SD rats, C57BL/6 mice and beagle dogs) and better target loading, especially in terms of the higher hepatic level of the pharmacologically active metabolite TFV-DP, which was tightly related to anti-HBV efficacy. Further analysis indicated that stability in intestinal fluid determined the actual amount of TFV prodrug at the absorption site, and hepatic/intestinal stability determined the maintenance amount of prodrug in circulation, both of which influenced the oral bioavailability of TFV prodrugs. In conclusion, our research revealed that improved pharmacokinetics of TFV ester prodrugs (especially intestinal stability) strengthened the inhibition of HBV replication and the rebalance of hepatocellular metabolism, which provides new insights and a basis for the design, modification and evaluation of new TFV prodrugs in the future.

8.
Artículo en Inglés | MEDLINE | ID: mdl-35954584

RESUMEN

With the continuous expansion of urban scale with dense population and traffic and the gradual improvement of residents' requirements for environmental quality, the traditional evaluation method relying on acoustic energy is not enough to reflect the feelings of urban crowds about acoustic environment quality. The acoustic environment quality evaluation method based on human subjective perception has gradually become one of the research focuses in the field of environmental noise control. In recent years, various subjective and objective acoustic characteristic parameters have been introduced into the study of acoustic environment assessment in the global literature. However, the extraction of "effective characteristics" from a large number of physical and psychoacoustic characteristics contained in acoustic signals and the creation of a scientific and efficient subjective evaluation model have always been key technical problems in the field of acoustic environment evaluation. Based on subjective human perceptions, the overall acoustic environment quality evaluation of urban open spaces is studied in this paper. Based on the "effective characteristic" parameters and the subjective characteristic proposed in the previous research, including equivalent continuous A-weighted sound pressure level (LA), the difference between median noise and ambient background noise (L50 - L90), Sharpness (Sh), as well as satisfaction (Sat), the multivariable linear regression algorithm is used to further study the intrinsic correlation between the proposed "effective characteristics" and subjective perception. Then, a satisfaction evaluation model of the acoustic environment based on "effective characteristics" is built in this paper. Furthermore, the soundwalk evaluation experiment and the MATLAB numerical simulation experiment are carried out, which verify that the prediction accuracy of the proposed model is more than 92%, the consistency of satisfaction level is more than 88%, as well as the changes in the values of Sh and L50 - L90 have a significant impact on the satisfaction prediction of the proposed model. It shows that the proposed "effective characteristics" more comprehensively describe the quality level of the regional acoustic environment in urban open space compared with a single LA index, and the proposed acoustic environment satisfaction evaluation model based on "effective characteristics" has significant accuracy superiority and regional applicability.


Asunto(s)
Acústica , Sonido , Humanos , Ruido , Satisfacción Personal , Psicoacústica
9.
Biomater Sci ; 10(15): 4356-4366, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35786722

RESUMEN

Hepatitis B represents a major global public health burden, which is caused by the hepatitis B virus (HBV) with a high infection rate. Although several anti-HBV drugs have been developed for clinical treatment of hepatitis B, the current therapeutic strategies still suffer from undeniable adverse effects, insufficient efficacy after systemic administration and chronic inflammation. Here, we develop a carrier-free metal-organic hybrid nanoassembly that is co-loaded with tenofovir (TFV), an anti-viral agent and phosphorylated glycyrrhetinic acid (GAP), an anti-inflammatory compound (TFV/GAP/NA) to enhance the anti-HBV effect and alleviate the inflammatory response for hepatitis B treatment. The nanoassembly is easily prepared through the ionic interactions between the anionic phosphonate/phosphate groups from TFV/GAP and the zirconium cation, which has a stable nanostructure and a high drug-loading capacity. The nanoassembly prolongs the circulation time with reduced drug leakage in the blood and elevates drug accumulation in the liver after intravascular administration. After internalization mediated by the GAP ligand-GA receptor interaction, TFV/GAP/NA disassembles by the phosphatase-triggered degradation of the phosphate ester bonds in GAP and releases TFV, GAP and GA within the HBV-positive hepatocytes. The released TFV interferes with the HBV polymerase to inhibit the viral DNA replication, while the released GAP and GA suppress the pro-inflammatory protein expression. In mouse models, treatment with TFV/GAP/NA inhibits HBV production and alleviates inflammation-mediated liver injury.


Asunto(s)
Antivirales , Hepatitis B , Adenina/farmacología , Animales , Antivirales/farmacología , Replicación del ADN , ADN Viral/farmacología , ADN Viral/uso terapéutico , Hepatitis B/tratamiento farmacológico , Virus de la Hepatitis B/metabolismo , Inflamación/tratamiento farmacológico , Ratones , Organofosfatos , Fosfatos , Tenofovir/farmacología , Tenofovir/uso terapéutico , Replicación Viral
10.
Occup Environ Med ; 79(4): 253-258, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34969777

RESUMEN

BACKGROUND: Although the therapeutic effect of antineoplastic drugs is incontestable, these agents can also potentially act as carcinogens, mutagens and/or teratogens in people. The aim of this study was to assess the effect of occupational exposure to antineoplastic drugs on DNA damage, assessed by the comet assay and cytokinesis-block micronucleus (CBMN) assay, in nurses. METHODS: The cross-sectional study enrolled 305 nursing staff members from 7 public hospitals in Shenzhen who handled antineoplastic drugs, and 150 healthy nursing staff members who were not exposed to antineoplastic drugs as the control group. DNA damage was assessed by the comet and CBMN assay. Multiple linear regressions and logistic regressions models were used to analyse the effect of occupational exposure to antineoplastic drugs on DNA damage. RESULTS: After adjustment for confounding factors, compared with non-exposure to antineoplastic drugs, exposure to antineoplastic drugs was positively related to tail moment, olive moment, tail length and tail DNA per cent, and adjusted ß or OR (95% CI) was 0.17 (0.08 to 0.26), 0.18 (0.10 to 0.27), 1.03 (0.47 to 1.60) and 1.16 (1.04 to 1.29) (all p<0.05). Moreover, similar significant relationships were observed for the biomarkers of the CBMN assay. Additionally, other than age, there was no interaction between antineoplastic drug exposure and other variables for the levels of biomarkers of the CBMN assay and the comet assay. CONCLUSIONS: The present results showed that exposure to antineoplastic drugs was positively related to the risk of DNA damage in nurses. The results imply that occupational exposure to antineoplastic agents is an important global public health problem that requires urgent attention.


Asunto(s)
Antineoplásicos , Exposición Profesional , Antineoplásicos/efectos adversos , Biomarcadores , Ensayo Cometa , Estudios Transversales , Daño del ADN , Humanos , Linfocitos , Pruebas de Micronúcleos/métodos , Exposición Profesional/efectos adversos , Exposición Profesional/análisis
11.
Int J Mol Sci ; 22(24)2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34948018

RESUMEN

Objective: Prostate cancer (PCa) is the most common malignant tumor diagnosed in men in developed countries. In developing countries, the PCa morbidity and mortality rates are also increasing rapidly. Since androgen receptor (AR) is a key driver and plays a critical role in the regulation of PCa development, AR-targeted agents provide a key component of current therapy regimens. However, even new-generation AR antagonists are prone to drug resistance, and there is currently no effective strategy for overcoming advanced PCa aggressiveness, including drug-resistance progression. The aim of this study was to evaluate the potential efficacy and novel therapy strategy of proxalutamide (a newly developed AR antagonist) in PCa. Methods: Four PCa cell lines with various biological heterogeneities were utilized in this study, namely, androgen-sensitive/-insensitive with/without AR expression. Proliferation, migration and apoptosis assays in PCa cells were used to evaluate the effective therapeutic activity of proxalutamide. The changes in lipid droplet accumulation and lipidomic profiles were analyzed to determine the influence of proxalutamide on lipogenesis in PCa cells. The molecular basis of the effects of proxalutamide on lipogenesis and the AR axis was then further investigated. Results: Proxalutamide significantly inhibited the proliferation and migration of PCa cells, and its inhibitory effect was superior to that of enzalutamide (Enz, second-generation AR antagonist). Proxalutamide induced the caspase-dependent apoptosis of PCa cells. Proxalutamide significantly diminished the level of lipid droplets in PCa cells, changed the lipid profile of PCa cells and reduced the content of most lipids (especially triglycerides) in PCa cells. Proxalutamide attenuated de novo lipogenesis by inhibiting the expression of ATP citrate lyase (ACL), acetyl CoA carboxylase (ACC), fatty acid synthase (FASN) and sterol regulatory element-binding protein-1 (SREBP-1). Moreover, proxalutamide also decreased AR expression in PCa cells, and its inhibitory effect on lipogenesis did not depend on its ability to down-regulate AR expression. However, Enz had no effect on AR expression, lipid accumulation or lipid de novo synthesis in PCa cells. Conclusions: By co-targeting the AR axis and endogenous adipogenesis, a novel and promising strategy was established for proxalutamide to combat the progress of PCa. The unique effect of proxalutamide on the metabolic reprogramming of PCa provides a potential solution to overcome the resistance of current AR-targeted therapy, which will help to effectively prolong its clinical service life.


Asunto(s)
Lipogénesis/efectos de los fármacos , Oxazoles/farmacología , Neoplasias de la Próstata/metabolismo , Receptores Androgénicos/metabolismo , Tiohidantoínas/farmacología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Lipidómica , Masculino , Células PC-3 , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Receptores Androgénicos/genética , Transducción de Señal/efectos de los fármacos
12.
Dalton Trans ; 47(42): 15189-15196, 2018 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-30320854

RESUMEN

Nanomaterials with hierarchical structures have attracted much attention recently due to their impressive behavior in many fields. Herein, hierarchical Cu2S nanorods with monoclinic and hexagonal phases are first in situ grown on copper sheets by simple hydrothermal methods. The solvent largely influences the feature of Cu2S nanorods during the growth process and the proposed mechanism is elaborately elucidated for these different Cu2S nanorods. Owing to their wheat-like architecture and higher electrical conductivity, the hexagonal Cu2S nanorods exhibit superior electrochemical performance with a specific capacitance of 346 mF cm-2 at 5 mA cm-2 and more than 90% capacitance after 2000 cycles. The solid-state asymmetrical supercapacitors based on the hexagonal Cu2S electrodes have a specific capacitance of 172 mF cm-2 at 5 mA cm-2 and excellent electrochemical stability with ∼90% capacitance after 2000 cycling tests. Moreover, the hierarchical Cu2S nanorods show great photocatalytic ability in the degradation of methylene blue (MB) and rhodamine B (RhB) dyes with the assistance of H2O2 under visible light. This work provides a way to fabricate copper sulfides with hierarchical structures and multi-functions.

13.
Data Brief ; 17: 1331-1335, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29876488

RESUMEN

In this article, we provide the data analysis between controllable variables and the performance of CuS crackle based electrode, there are four important factors which could influence the formation of cracks, the colloid concentration, drying temperature, colloid dosage and ambient humidity. We carried out and summed nineteen controlled data experiments below and other variates which could affect the performance were discussed in this article.

14.
J Pharm Biomed Anal ; 155: 157-168, 2018 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-29631076

RESUMEN

Corylin, an phenolic compound from Psoralea corylifolia, has been reported with various pharmacological properties but has poor bioavailability due to massive metabolism. In this study, twelve metabolites of corylin mainly involving in oxidation, hydration, glucuronidation and sulfation were detected in mice. Furthermore, the oxidation and hydration of corylin (M4) in human liver microsomes (HLM) and human intestine microsomes (HIM) were both efficient with high CLint (intrinsic clearance) values of 24.29 and 42.85 µL/min/mg, respectively. CYP1A1, 1B1 and 2C19 contributed most for M4 with the CLint values of 26.63, 33.09 and 132.41 µL/min/mg, respectively. Besides, M4 was strongly correlated with phenacetin-N-deacetylation (r = 0.885, p = 0.0001) and tolbutamide-4-oxidation (r = 0.727, p = 0.001) in twelve individual HLMs, respectively. In addition, corylin was efficiently glucuronidated (M7) in HLM (125.33 µL/min/mg) and in HIM (108.74 µL/min/mg). UGT1A1 contributed the most for M7 with the CLint value of 122.32 µL/min/mg. Meanwhile, M7 was significantly correlated with ß-estradiol-3-O-glucuronidation (r = 0.742, p = 0.006) in twelve individual HLMs. Moreover, the metabolism of corylin showed marked species differences. Taken together, corylin was subjected to massive first-pass metabolism in liver and intestine, while CYP1A1, 1B1, 2C19 and UGT1A1 were the main contributors. Finally, the proposed metabolic pathway of corylin involed CYP and UGT isoforms were summarized, which could help to understand the metabolic fate of corylin in vivo.


Asunto(s)
Flavonoides/metabolismo , Animales , Citocromo P-450 CYP1A1/metabolismo , Glucurónidos/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Cinética , Hígado/metabolismo , Masculino , Metabolómica/métodos , Ratones , Microsomas Hepáticos/metabolismo , Fenoles/metabolismo , Especificidad de la Especie
15.
Food Funct ; 9(3): 1410-1423, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29318243

RESUMEN

Active efflux transport of glucuronides out of cells is a critical process in elimination of drugs and food-derived compounds. Wushanicaritin, a natural polyphenol from Epimedium species, has shown many biological activities. However, the transporters responsible for excretion of wushanicaritin glucuronides still remain undefined. Herein, chemical inhibitors (Ko143, MK571, dipyridamole and leukotriene C4) and single stable knocked-down efflux transporters (BCRP, MRP1, MRP3 and MRP4) were used to determine the contributions of efflux transporters to glucuronide efflux and cellular glucuronidation in UGT1A1-overexpressing HeLa cells (HeLa1A1). Knock-down of transporters was performed by stable transfection of short hairpin RNA (shRNA) using lentiviral vectors. The HeLa1A1 cell lysate catalyzed wushanicaritin glucuronidation, generating wushanicaritin-3-O-glucuronide and wushanicaritin-7-O-glucuronide. Ko143 (a dual inhibitor of BCRP, 5-20 µM) caused a marked decrease in excretion rate (maximal 53.4%) and increase of intracellular glucuronides (maximal 86.0%), while MK-571 (an inhibitor of MRPs, 5-20 µM) resulted in a significant reduction in excretion rate (maximal 64.6%) and rise of intracellular glucuronides (maximal 98.0%). By contrast, dipyridamole and leukotriene C4 showed no inhibitory effects on glucuronide excretion. Furthermore, shRNA-mediated silencing of a target transporter led to a marked reduction in the excretion rate of wushanicaritin glucuronides (maximal 33.8% for BCRP; 25.9% for MRP1; 26.7% for MRP3; 39.3% for MRP4). Transporter silencing also led to substantial decreases in efflux clearance (maximal 61.5% for BCRP; 48.7% for MRP1; 35.1% for MRP3; 63.1% for MRP4). In conclusion, chemical inhibition and gene silencing results suggested that BCRP, MRP1, MRP3 and MRP4 were significant contributors to excretion of wushanicaritin glucuronides.


Asunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Medicamentos Herbarios Chinos/metabolismo , Flavonoides/metabolismo , Glucurónidos/metabolismo , Glucuronosiltransferasa/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas de Neoplasias/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Transporte Biológico/efectos de los fármacos , Dicetopiperazinas/farmacología , Dipiridamol/farmacología , Medicamentos Herbarios Chinos/farmacología , Epimedium/química , Flavonoides/farmacología , Técnicas de Silenciamiento del Gen , Silenciador del Gen , Glucuronosiltransferasa/genética , Células HeLa , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Humanos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas de Neoplasias/genética , Propionatos/farmacología , Quinolinas/farmacología , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo
16.
Xenobiotica ; 48(4): 357-367, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28443723

RESUMEN

1. Icaritin is a natural flavonoid with anti-osteoporosis activity. This study aimed to characterize icaritin glucuronidation by pooled human liver microsomes (HLM) and pooled human intestine microsomes (HIM), and to determine the contribution of individual UDP-glucuronosyltrans-ferase (UGT) enzyme to icaritin glucuronidation. 2. Glucuronidation rates were determined by incubating icaritin with uridine diphosphate glucuronic acid (UDPGA)-supplemented microsomes. Kinetic parameters were derived by appropriate model fitting. Relative activity factors and activity correlation analysis were performed to identify main UGT isoforms. 3. UGT1A3, 1A7, 1A8, 1A9 and 2B7 were mainly responsible for catalyzing the formation of two glucuronides (G1 and G2). Icaritin 3-O-glucuronidation (G1) was significantly correlated with Chenodeoxycholic acid (CDCA) glucuronidation (r = 0.787, p = 0.002), propofol glucuronidation (r = 0.661, p = 0.019) and Zidovudine (AZT) glucuronidation (r = 0.805, p = 0.002). Similarly, icaritin 7-O-glucuronidation (G2) was also correlated with CDCA glucuronidation (r = 0.640, p = 0.025), propofol glucuronidation (r = 0.592, p = 0.043) and AZT glucuronidation (r = 0.661, p = 0.019). In addition, UGT1A3, 1A9 and 2B7 contributed 37.5, 33.8 and 21.3% for G1 in pooled HLM, respectively. Also, UGT1A3, 1A9 and 2B7 contributed 34.3, 20.0 and 8.6% for G2 in pooled HLM, respectively. 4. Icaritin was subjected to significant glucuronidation, wherein UGT1A3, 1A7, 1A8, 1A9 and 2B7 were main contributing enzymes.


Asunto(s)
Flavonoides/farmacocinética , Glucuronosiltransferasa/metabolismo , Microsomas Hepáticos/enzimología , Biocatálisis , Humanos , Cinética , UDP Glucuronosiltransferasa 1A9
17.
Int J Mol Sci ; 18(9)2017 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-28925930

RESUMEN

Wushanicaritin, a natural polyphenol compound, exerts many biological activities. This study aimed to characterize wushanicaritin glucuronidation by pooled human liver microsomes (HLM), human intestine microsomes and individual uridine diphosphate-glucuronosyltransferase (UGT) enzyme. Glucuronidation rates were determined by incubating wushanicaritin with uridine diphosphoglucuronic acid-supplemented microsomes. Kinetic parameters were derived by appropriate model fitting. Reaction phenotyping, the relative activity factor (RAF) and activity correlation analysis were performed to identify the main UGT isoforms. Wushanicaritin glucuronidation in HLM was efficient with a high CLint (intrinsic clearance) value of 1.25 and 0.69 mL/min/mg for G1 and G2, respectively. UGT1A1 and 1A7 showed the highest activities with the intrinsic clearance (CLint) values of 1.16 and 0.38 mL/min/mg for G1 and G2, respectively. In addition, G1 was significantly correlated with ß-estradiol glucuronidation (r = 0.847; p = 0.0005), while G2 was also correlated with chenodeoxycholic acid glucuronidation (r = 0.638, p = 0.026) in a bank of individual HLMs (n = 12). Based on the RAF approach, UGT1A1 contributed 51.2% for G1, and UGT1A3 contributed 26.0% for G2 in HLM. Moreover, glucuronidation of wushanicaritin by liver microsomes showed marked species difference. Taken together, UGT1A1, 1A3, 1A7, 1A8, 1A9 and 2B7 were identified as the main UGT contributors responsible for wushanicaritin glucuronidation.


Asunto(s)
Flavonoides/metabolismo , Glucuronosiltransferasa/metabolismo , Mucosa Intestinal/metabolismo , Microsomas Hepáticos/metabolismo , Animales , Disacáridos/metabolismo , Perros , Cobayas , Haplorrinos , Humanos , Inactivación Metabólica , Intestinos/citología , Isoformas de Proteínas/metabolismo , Conejos , Ratas , Especificidad de la Especie
18.
Nanoscale ; 9(11): 3826-3833, 2017 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-28197585

RESUMEN

The rapid development of modern electronics has given rise to a higher demand for flexible and wearable energy sources. Flexible transparent conducting electrodes (TCEs) are one of the essential components of flexible/wearable thin-film solar cells (SCs). In this regard, we present highly transparent and conducting CuS-nanosheet (NS) networks with an optimized sheet resistance (Rs) as low as 50 Ω sq-1 at 85% transmittance as a counter electrode (CE) for flexible quantum-dot solar cells (QDSCs). The CuS NS network electrode exhibits remarkable mechanical flexibility under bending tests compared to traditional ITO/plastic substrates and sputtered CuS films. Herein, CuS NS networks not only served as conducting films for collecting electrons from the external circuit, but also served as superior catalysts for reducing polysulfide (S2-/Sx2-) electrolytes. A power conversion efficiency (PCE) up to 3.25% was achieved for the QDSCs employing CuS NS networks as CEs, which was much higher than those of the devices based on Pt networks and sputtered CuS films. We believe that such CuS network TCEs with high flexibility, transparency, conductivity and catalytic activity could be widely used in making wearable electronic products.

19.
Yao Xue Xue Bao ; 47(9): 1134-40, 2012 Sep.
Artículo en Chino | MEDLINE | ID: mdl-23227541

RESUMEN

This study is to establish an artificial neural network (ANN) for predicting blood tacrolimus concentration in liver transplantation recipients. Tacrolimus concentration samples (176 samples) from 37 Chinese liver transplantation recipients were collected. ANN established after network parameters were optimized by using momentum method combined with genetic algorithm. Furthermore, the performance of ANN was compared with that of multiple linear regression (MLR). When using accumulated dose of 4 days before therapeutic drug monitoring (TDM) of tacrolimus concentration as input factor, mean prediction error and mean absolute prediction error of ANN were 0.02 +/- 2.40 ng x mL(-1) and 1.93 +/- 1.37 ng x mL(-1), respectively. The absolute prediction error of 84.6% of testing data sets was less than 3.0 ng x mL(-1). Accuracy and precision of ANN are superior to those of MLR. The correlation, accuracy and precision of ANN are good enough to predict blood tacrolimus concentration.


Asunto(s)
Monitoreo de Drogas/métodos , Inmunosupresores/sangre , Trasplante de Hígado , Redes Neurales de la Computación , Tacrolimus/sangre , Adulto , Anciano , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad
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