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1.
Angew Chem Int Ed Engl ; : e202406888, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39007540

RESUMEN

Transition metal/p-block compounds are regarded as the most essential materials for electrochemical energy converting systems involving various electrocatalysis. Understanding the role of p-block element on the interaction of key intermediates and interfacial water molecule orientation at the polarized catalyst-electrolyte interface during the electrocatalysis is important for rational designing advanced p-block modified metal electrocatalysts. Herein, taking a sequence of ruthenium phosphides (including Ru2P, RuP and RuP2) as model catalysts, we establish a volcanic-relation between P-proportion and alkaline hydrogen oxidation reaction (HOR) activity. The dominant role of P for regulating hydroxyl binding energy is validated by active sites poisoning experiments, pH-dependent infection-point behavior, in situ surface enhanced absorption spectroscopy, and density functional theory calculations, in which P could tailor the d-band structure of Ru, optimize the hydroxyl adsorption sites across the Ru-P moieties, thereby leading to improved proportion of strongly hydrogen-bonded water and facilitated proton-coupled electron transfer process, which are responsible for the enhanced alkaline HOR performance.

2.
Mar Pollut Bull ; 205: 116570, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38861798

RESUMEN

The study applied a tiered ecological risk assessment method to evaluate the long-term status and trend of the ecological risks of dissolved heavy metals from 2011 to 2019 in the Yangtze River Estuary and Zhejiang coastal waters, China. The results for spring, summer, and autumn of 2019 indicated that Pb, Cd, and Zn posed no adverse ecological risk, Cu posed a potential ecological risk, and As posed an ecological risk. The annual results from 2011 to 2019 suggested that Pb, Cd, and Zn posed no adverse ecological risks, and As and Cu posed an ecological risk. The trend analysis in the nine years showed that the ecological risk of Cu is gradually decreasing, while that of As is still a concern. The overall trend is attributed to the environmental protection policies that reduced these contaminants' terrestrial sources and atmospheric sources.


Asunto(s)
Monitoreo del Ambiente , Estuarios , Metales Pesados , Ríos , Contaminantes Químicos del Agua , Metales Pesados/análisis , China , Medición de Riesgo , Contaminantes Químicos del Agua/análisis , Ríos/química , Agua de Mar/química
3.
Biomed Pharmacother ; 176: 116908, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38850668

RESUMEN

Non-alcoholic fatty liver disease (NAFLD), particularly advanced non-alcoholic steatohepatitis (NASH), leads to irreversible liver damage. This study investigated the therapeutic effects and potential mechanism of a novel extract from traditional Chinese medicine Alisma orientale (Sam.) Juzep (AE) on free fatty acid (FFA)-induced HepG2 cell model and high-fat diet (HFD) + carbon tetrachloride (CCl4)-induced mouse model of NASH. C57BL/6 J mice were fed a HFD for 10 weeks. Subsequently, the mice were injected with CCl4 to induce NASH and simultaneously treated with AE at daily doses of 50, 100, and 200 mg/kg for 4 weeks. At the end of the treatment, animals were fasted for 12 h and then sacrificed. Blood samples and liver tissues were collected for analysis. Lipid profiles, oxidative stress, and histopathology were examined. Additionally, a polymerase chain reaction (PCR) array was used to predict the molecular targets and potential mechanisms involved, which were further validated in vivo and in vitro. The results demonstrated that AE reversed liver damage (plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hepatocyte ballooning, hepatic steatosis, and NAS score), the accumulation of hepatic lipids (TG and TC), and oxidative stress (MDA and GSH). PCR array analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that AE protects against NASH by regulating the adipocytokine signaling pathway and influencing nuclear receptors such as PPARα. Furthermore, AE increased the expression of peroxisome proliferator-activated receptor gamma coactivator-1α (PPARGC1α) and reversed the decreased expression of PPARα in NASH mice. Moreover, in HepG2 cells, AE reduced FFA-induced lipid accumulation and oxidative stress, which was dependent on PPARα up-regulation. Overall, our findings suggest that AE may serve as a potential therapeutic approach for NASH by inhibiting lipid accumulation and reducing oxidative stress specifically through the PPARα pathway.


Asunto(s)
Alisma , Dieta Alta en Grasa , Enfermedad del Hígado Graso no Alcohólico , Extractos Vegetales , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Alisma/química , Tetracloruro de Carbono , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Células Hep G2 , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/aislamiento & purificación , PPAR alfa/metabolismo , Transducción de Señal/efectos de los fármacos
4.
Microvasc Res ; 151: 104600, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37666318

RESUMEN

Atrial fibrillation (AF) is a cardiac disease characterized by disordered atrial electrical activity. Atrial inflammation and fibrosis are involved in AF progression. Costunolide (COS) is a sesquiterpene lactone containing anti-inflammatory and anti-fibrotic activities. This study aims to explore the underlying mechanisms by which COS protects against AF. Male C57BL/6 mice (8- to 10-week-old) were infused with angiotensin (Ang) II for 3 weeks. Meanwhile, different doses of COS (COS-L: 10 mg/kg, COS-H: 20 mg/kg) were administered to mice by intragastric treatment. The results showed irregular and rapid heart rates in Ang II-treated mice. Moreover, the levels of inflammatory cytokines and fibrotic factors were elevated in mice. COS triggered a reduction of Ang II-induced inflammation and fibrosis, which conferred a protective effect. Mechanistically, mitochondrial dysfunction with mitochondrial respiration inhibition and aberrant ATP levels were observed after Ang II treatment. Moreover, Ang-II-induced excessive reactive oxygen species caused oxidative stress, which was further aggravated by inhibiting Nrf2 nuclear translocation. Importantly, COS diminished these Ang-II-mediated effects in mice. In conclusion, COS attenuated inflammation and fibrosis in Ang-II-treated mice by alleviating mitochondrial dysfunction and oxidative stress. Our findings represent a potential therapeutic option for AF treatment.


Asunto(s)
Fibrilación Atrial , Enfermedades Mitocondriales , Sesquiterpenos , Ratones , Masculino , Animales , Fibrilación Atrial/inducido químicamente , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/prevención & control , Angiotensina II/farmacología , Ratones Endogámicos C57BL , Sesquiterpenos/efectos adversos , Estrés Oxidativo , Mitocondrias/metabolismo , Fibrosis , Inflamación/tratamiento farmacológico , Inflamación/prevención & control
5.
Mar Pollut Bull ; 182: 113975, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35939928

RESUMEN

Dissolved heavy metal pollution in the ocean is becoming an environmental concern. Their distribution patterns are complex and influenced by multiple factors in the coastal ocean. Therefore, more investigations are needed to understand their behavior in the seawater. This study systematically investigated the distribution of Cu, Pb, Cd, As, Zn and seawater properties in the surface and bottom water off the Yangtze River Estuary, East China Sea in spring, summer and autumn, 2019. The results showed significant spatiotemporal distribution that three-zone-pattern of estuary, nearshore, and offshore can be divided. While sources, hydrodynamics, biological uptake and sediment resuspension affected the overall distribution, dissolved oxygen and pH dominantly influenced the estuary and offshore respectively, with more complex factors in the nearshore. Low ecological risks were assessed during the study, but global warming, ocean acidification and hypoxia are essential concerns to understand the biogeochemistry of dissolved heavy metals in the ocean.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente/métodos , Estuarios , Sedimentos Geológicos/química , Concentración de Iones de Hidrógeno , Metales Pesados/análisis , Ríos/química , Agua de Mar , Contaminantes Químicos del Agua/análisis
6.
Nanomaterials (Basel) ; 11(2)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670212

RESUMEN

Recently, different kinds of energy band structures have been utilized to improve the photoelectric properties of zinc oxide (ZnO). In this work, ZnO nanorods were prepared by the hydrothermal method and then decorated with silver sulfide (Ag2S)/zinc sulfide (ZnS) via two-step successive ionic layer adsorption and reaction method. The photoelectric properties of nanocomposites are investigated. The results show that ZnO decorated with Ag2S/ZnS can improve the photocurrent of photodetectors from 0.34 to 0.56 A at bias of 9 V. With the immersion time increasing from 15 to 60 minutes, the photocurrent of photodetectors increases by 0.22 A. The holes in the valence band of ZnO can be transferred to the valence band of ZnS and Ag2S, which promotes the separation and suppresses the recombination of hole-electron pairs generated in ZnO. Moreover, electrons excited by ultraviolet (UV) light in Ag2S can also be injected into the conduction band of ZnO, which causes the photocurrent to increase more than the ZnO photodetector.

7.
Oncotarget ; 7(22): 32617-27, 2016 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-27119233

RESUMEN

Glioblastoma (GBM) is the most lethal primary nervous system cancer, but due to its rarity and complexity, its pathogenesis is poorly understood. To identify potential tumorigenic factors in GBM, we screened antibody-based cytokine arrays and found that CCL11 was upregulated. We then demonstrated in vitro that both CCL11 and its receptor, CCR3, were overexpressed and promoted the proliferation, migration and invasion of cancer cells. To examine the clinical significance of CCL11/CCR3, 458 GBM samples were divided into a training cohort with 225 cases and a test cohort containing 233 cases. In the training set, immunohistochemical analysis showed overexpression of CCL11 and CCR3 were correlated with unfavorable overall survival (OS). We further developed a prognostic classifier combining CCL11 and CCR3 expression and Karnofsky performance status (KPS) for predicting one-year survival in GBM patients. Receiver operating characteristic (ROC) analysis demonstrated that this predictor achieved 90.7% sensitivity and 73.4% specificity. These results were validated with the test sample set. Our findings suggest that CCL11-CCR3 binding is involved in the progression of GBM and may prompt a novel therapeutic approach. In addition, CCL11 and CCR3 expression, combined with KPS, may be used as an accurate predictor of one-year survival in GBM patients.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Quimiocina CCL11/biosíntesis , Glioblastoma/metabolismo , Receptores CCR3/biosíntesis , Biomarcadores de Tumor/biosíntesis , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular/fisiología , Quimiocina CCL11/genética , Femenino , Glioblastoma/genética , Glioblastoma/patología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Receptores CCR3/genética , Receptores CCR3/metabolismo
8.
Endocrine ; 47(3): 764-71, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24590293

RESUMEN

Diabetes mellitus has been identified as a major risk factor for cardiovascular diseases. High glucose-induced endothelial dysfunction and apoptosis is an important pathological feature of diabetic vasculopathy. Neferine, an alkaloid ingredient in lotus seed embryo has many biological actions such as anticancer and antioxidant. But little is known about whether Neferine protects endothelial cells against high glucose-induced oxidative stress and apoptosis. The present study was conducted to investigate the preventive effects of Neferine on hyperglycemia-induced injury of human umbilical vein endothelial cells (HUVECs). Our study showed that Neferine pretreatment effectively suppressed high glucose-induced HUVECs apoptosis. Also, Neferine pretreatment inhibited the augment of reactive oxygen species (ROS) in high glucose-treated HUVECs. The changes of SOD and MDA level in high glucose-treated HUVECs were also prevented by Neferine. Further study showed that Neferine did not affect the phosphorylation of JNK and p38 in high glucose-treated HUVECs. Interestingly, Neferine markedly inhibited high glucose-induced activation of PI3K/Akt pathway in HUVECs. High glucose-induced activation of NF-κB signal was also obviously suppressed by Neferine pretreatment. Collectively, we found that Neferine inhibited high glucose-induced endothelial apoptosis via blocking ROS/Akt/NF-κB pathway, which provides the evidence for using Neferine to treat diabetic vasculopathy.


Asunto(s)
Apoptosis/efectos de los fármacos , Bencilisoquinolinas/farmacología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Hiperglucemia/metabolismo , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Estrés Oxidativo/efectos de los fármacos , Fosforilación/efectos de los fármacos
9.
World J Microbiol Biotechnol ; 29(5): 933-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23269506

RESUMEN

The endophytic fungus XJ-AC03, which was isolated from the healthy roots of Aconitum leucostomum, produced aconitine when grown in potato dextrose agar (PDA) medium. The presence of aconitine was confirmed by the chromatographic and spectroscopic analyses. The yield of aconitine was recorded as 236.4 µg/g by high performance liquid chromatography (HPLC). The mass spectrometry was shown to be identical to authentic aconitine. Further analysis with nuclear magnetic resonance (NMR) spectroscopy to show the chemical structure of the fungal aconitine indicated that the fungal aconitine produced an NMR spectrum identical to that of authentic aconitine. Strain XJ-AC03 was identified as Cladosporium cladosporioides by its characteristic culture morphology and ITS rDNA sequence analysis.


Asunto(s)
Aconitina/metabolismo , Aconitum/microbiología , Cladosporium/aislamiento & purificación , Cladosporium/metabolismo , Endófitos/aislamiento & purificación , Endófitos/metabolismo , Aconitina/análisis , Cromatografía Líquida de Alta Presión , Cladosporium/genética , Endófitos/genética
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