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1.
Dalton Trans ; 52(27): 9456-9464, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37366113

RESUMEN

The synthesis of furan-based platform chemicals from abundant and renewable biomass-based hexoses plays an important role in the development and utilization of biomass energy. The electrochemical 5-hydroxymethylfurfural oxidation reaction (HMFOR) represents a promising route for synthesizing the 2,5-furandicarboxylic acid (FDCA) product which is a high value-added biomass-based monomer. Interface engineering is an effective strategy to adjust the electronic structure, optimize the adsorption of intermediates, and expose more active sites, thus attracting extensive attention for designing efficient HMFOR electrocatalysts. Herein, a NiO/CeO2@NF heterostructure with an abundant interface is designed for boosting the HMFOR performance under alkaline conditions. At 1.475 V vs. RHE, the conversion of HMF is nearly 100%, the selectivity of FDCA is 99.0%, and the faradaic efficiency is as high as 98.96%. The NiO/CeO2@NF electrocatalyst also exhibits robust stability for HMFOR for 10 cycles. When coupled with the cathode hydrogen evolution reaction (HER) in alkaline medium, the yields of FDCA and hydrogen production are 197.92 and 600 µmol cm-2 h-1, respectively. The NiO/CeO2@NF catalyst is also suitable for the electrocatalytic oxidation of other biomass-derived platform compounds. The abundant interface between NiO and CeO2, which can regulate the electronic properties of Ce and Ni atoms, improve the oxidation state of Ni species, regulate intermediate adsorption, and promote electron/charge transfer, makes the most contribution to high HMFOR performance. This work will provide a simple route for the design of heterostructured materials and reveal the application prospect of interface engineering for promoting the upgrading of biomass derivatives.

2.
Eur J Med Res ; 28(1): 96, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36829258

RESUMEN

Bleeding is a major adverse event during clopidogrel treatment in patients with acute coronary syndrome (ACS). However, the potential mechanism affecting bleeding among individuals is unclear. Herein, we investigated the involvement of CYP2C19*2 and CYP2C19*3, as well as 10 miRNA polymorphisms, in bleeding in Chinese patients with ACS during the first year of clopidogrel treatment. The miR-6076 rs1463411 G polymorphism was significantly associated with the risk of bleeding (P < 0.001), and the rs1463411 GT + GG genotype significantly increased the risk of bleeding (adjusted odds ratio, 6.09; 95% confidence interval, 1.09-34.0; P < 0.001). Dual luciferase assay showed that miR-6076 significantly decreased the mRNA expression of P2RY12 (P < 0.05). P2RY12 mRNA and protein levels were significantly lower in cells transfected with miR-6076-G than in cells transfected with miR-6076-T (P < 0.05). The findings indicate that miR-6076 targets P2RY12 mRNA and that miR-6076 rs1463411 T/G polymorphisms differentially regulate P2RY12 mRNA and protein levels in cells. rs1463411 G polymorphism may increase the risk of bleeding during clopidogrel treatment in patients with ACS.


Asunto(s)
Síndrome Coronario Agudo , MicroARNs , Intervención Coronaria Percutánea , Humanos , Clopidogrel , Inhibidores de Agregación Plaquetaria/efectos adversos , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C19/metabolismo , Ticlopidina , Síndrome Coronario Agudo/genética , Hemorragia/etiología , Genotipo , Intervención Coronaria Percutánea/efectos adversos , Resultado del Tratamiento
3.
Cell Prolif ; 54(1): e12948, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33145869

RESUMEN

Metastasis refers to the progressive dissemination of primary tumour cells and their colonization of other tissues and is associated with most cancer-related mortalities. The disproportional and systematic distribution pattern of distant metastasis in different cancers has been well documented, as is termed metastatic organotropism, a process orchestrated by a combination of anatomical, pathophysiological, genetic and biochemical factors. Extracellular vesicles (EVs), nanosized cell-derived membrane-bound particles known to mediate intercellular communication, are now considered crucial in organ-specific metastasis. Here, we review and summarize recent findings regarding EV-associated organotropic metastasis as well as some of the general mechanisms by which EVs contribute to this important process in cancer and provide a future perspective on this emerging topic. We highlight studies that demonstrate a role of tumour-derived EVs in organotropic metastasis via pre-metastatic niche modulation. The bioactive cargo carried by EVs is of diagnostic and prognostic values, and counteracting the functions of such EVs may be a novel therapeutic strategy targeting metastasis. Further investigations are warranted to better understand the functions and mechanisms of EVs in organotropic metastasis and accelerate the relevant clinical translation.


Asunto(s)
Vesículas Extracelulares/patología , Metástasis de la Neoplasia , Neoplasias/patología , Animales , Vesículas Extracelulares/metabolismo , Humanos , Neoplasias/metabolismo
4.
J Nutr ; 150(5): 1303-1312, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32040591

RESUMEN

BACKGROUND: Metabolic endotoxemia is considered a cause for high-fat diet (HFD)-induced inflammation. However, convincing experimental evidence in humans is scant. OBJECTIVE: We determined whether a HFD or moderately HFD increases LPS and LPS-mediated cytokine production in the postprandial blood (PPB). METHODS: Ninety-eight volunteers (age: 37.3 ± 1.5 y) from the cross-sectional phenotyping study (PS) and 62 volunteers (age: 26.8 ± 1.2 y) from the intervention study (IS) consumed a breakfast containing 60% kcal fat (HF) and 36% kcal fat (moderately HF), respectively. For the IS, only the results from the placebo group are presented. Blood samples were probed for LPS-mediated cytokine production by incubating them with LPS inhibitor polymyxin B (PMB) for 24 h at 37°C besides the Limulus amebocyte lysate (LAL) assay. Repeated-measures ANOVA was used to compare the temporal changes of metabolic profiles and treatment outcomes. RESULTS: At least 87.5% of the plasma LPS measurements in 32 PS volunteers from each time point were below the LAL assay sensitivity (0.002 EU/mL). PMB suppressed IL-1ß (P = 0.035) and IL-6 (P = 0.0487) production in the 3 h PPB of the PS after 24 h incubation at 37°C compared to the vehicle control, suggesting the presence of LPS. However, the amount of LPS did not increase the cytokine concentrations in the 3 h PPB above the fasting concentrations. Such suppression was not detected in the PPB of the IS. Treating whole blood with lipoprotein lipase (LPL) significantly (P < 0.05) increased FFA and cytokine (IL-1ß, IL-6, TNF-α) concentrations in both studies. CONCLUSION: LPS may not be the major cause of postprandial inflammation in healthy adults consuming a moderately HF meal (36% kcal fat, similar to the typical American diet) or a HF meal (60% kcal fat). Plasma FFAs may modulate postprandial inflammation. The prevailing concept of HFD-induced metabolic endotoxemia requires careful re-evaluation. The PS was registered at clinicaltrials.gov as NCT02367287 and the IS as NCT02472171.


Asunto(s)
Dieta Alta en Grasa/efectos adversos , Inflamación/sangre , Inflamación/etiología , Lipopolisacáridos/sangre , Periodo Posprandial/fisiología , Adulto , Desayuno , Estudios Transversales , Citocinas/sangre , Método Doble Ciego , Ácidos Grasos no Esterificados/sangre , Femenino , Humanos , Lipopolisacáridos/antagonistas & inhibidores , Lipoproteína Lipasa/metabolismo , Masculino , Placebos , Polimixina B/farmacología
5.
Platelets ; 31(7): 897-905, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-31766967

RESUMEN

Clopidogrel therapy reduces the occurrence of major vascular events in acute coronary syndrome (ACS) patients, but treatment efficacy is variable. The present study aims to determine the mechanisms that underlie associations between certain miRNA polymorphisms and clinical outcomes of clopidogrel therapy. Our study focused on 9 miRNA single nucleotide polymorphisms in addition to CYP2C19*2 and CYP2C19*3. We found that the miR-605 rs2043556 AG genotype significantly decreased the risk of acute myocardial infarction (odds ratio, OR = 0.13, 95%CI 0.02-0.96, P = .045) and that the rs2043556 GG genotype significantly decreased the risk of unstable angina (OR = 0.19, 95%CI 0.05-0.65, P = .008) in ACS patients receiving clopidogrel therapy for more than one year. Dual-luciferase analysis indicated that miR-605 significantly decreased the mRNA expression of CYP2B6 and P2RY12 (P < .01). In cells treated with miR-605-A, the protein and mRNA expression of CYP2B6 and P2RY12 were significantly lower than that of cells treated with miR-605-G (P < .05). The results demonstrate that miR-605 targets the mRNA of the CYP2B6 and P2RY12 genes, and that rs2043556 A/G polymorphisms in miR-605 modulate the mRNA and protein expression of CYP2B6 and P2RY12 differently, which may impact the effect of clopidogrel in ACS patients.


Asunto(s)
Síndrome Coronario Agudo/tratamiento farmacológico , Síndrome Coronario Agudo/genética , Clopidogrel/uso terapéutico , Citocromo P-450 CYP2B6/metabolismo , MicroARNs/metabolismo , Antagonistas del Receptor Purinérgico P2Y/uso terapéutico , Receptores Purinérgicos P2Y12/metabolismo , Síndrome Coronario Agudo/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Clopidogrel/farmacología , Citocromo P-450 CYP2B6/genética , Femenino , Genotipo , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Receptores Purinérgicos P2Y12/genética
6.
Viruses ; 6(3): 1091-111, 2014 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-24618810

RESUMEN

Decay accelerating factor (DAF/CD55) is targeted by many pathogens for cell entry. It has been implicated as a co-receptor for hantaviruses. To examine the binding of hantaviruses to DAF, we describe the use of Protein G beads for binding human IgG Fc domain-functionalized DAF ((DAF)2-Fc). When mixed with Protein G beads the resulting DAF beads can be used as a generalizable platform for measuring kinetic and equilibrium binding constants of DAF binding targets. The hantavirus interaction has high affinity (24-30 nM; k(on) ~ 105 M⁻¹ s⁻¹, k(off) ~ 0.0045 s⁻¹). The bivalent (DAF)2-Fc/SNV data agree with hantavirus binding to DAF expressed on Tanoue B cells (K(d) = 14.0 nM). Monovalent affinity interaction between SNV and recombinant DAF of 58.0 nM is determined from competition binding. This study serves a dual purpose of presenting a convenient and quantitative approach of measuring binding affinities between DAF and the many cognate viral and bacterial ligands and providing new data on the binding constant of DAF and Sin Nombre hantavirus. Knowledge of the equilibrium binding constant allows for the determination of the relative fractions of bound and free virus particles in cell entry assays. This is important for drug discovery assays for cell entry inhibitors.


Asunto(s)
Antígenos CD55/metabolismo , Receptores Virales/metabolismo , Virus Sin Nombre/fisiología , Acoplamiento Viral , Humanos , Microesferas
7.
Talanta ; 81(3): 792-8, 2010 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-20298855

RESUMEN

Immunofiltration assay for mycotoxins in which nitrocellulose membrane (NCM) was used as a support and enzyme was used as the label has been developed since the late 1980s. As colloidal gold is a good labeling substance that can accelerate antibody-antigen reaction which result can be read directly by naked eyes, the colloidal gold particles could replace the enzyme to be labeled to antibody in aflatoxin B(1) (AFB(1)) immunoassay. Dot-immunogold filtration assay (DIGFA) of AFB(1) on NCM was developed in this study. At first, the colloidal gold was synthesized and colloidal gold-monoclonal antibody (McAb) conjugates against AFB(1) were prepared at pH 7.0 of colloidal gold solution, 0.018mg/mL of McAb. Then the colloidal gold-McAb conjugates were used to develop AFB(1) DIGFA, which detection time was only 15min, six times less than that of ELISA. With this method to determine the standard AFB(1) solution, the results demonstrated a visual detection limit of approximately 2ng/mL of AFB(1), which was similar to that of ELISA. This method had good specificities for AFG(1), AFG(2) and AFM(1) and a little cross-reactivity with AFB(2). 45 food samples collected from the markets were subjected to DIGFA and the results showed that one corn sample was positive and in agreement that of HPLC. It is suggested that DIGFA developed in current study has a potential use as a rapid and cost-effective screening tool for the determination of AFB(1) in foods in the field within 15min without complicated steps.


Asunto(s)
Aflatoxina B1/análisis , Técnicas de Química Analítica , Análisis de los Alimentos/métodos , Inmunohistoquímica/métodos , Aflatoxina B1/química , Anticuerpos Monoclonales/química , Coloides/química , Ensayo de Inmunoadsorción Enzimática/métodos , Filtración , Contaminación de Alimentos , Oro Coloide/química , Concentración de Iones de Hidrógeno , Inmunoensayo/métodos , Oryza , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta/métodos
8.
J Mass Spectrom ; 45(3): 235-40, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20014161

RESUMEN

Electrospray-generated precursor ions usually follow the 'even-electron rule' and yield 'closed shell' fragment ions. We characterize an exception to the 'even-electron rule.' In negative ion electrospray mass spectrometry (ES-MS), 2-(ethoxymethoxy)-3-hydroxyphenol (2-hydroxyl protected pyrogallol) easily formed a deprotonated molecular ion (M-H)(-) at m/z 183. Upon low-energy collision induced decomposition (CID), the m/z 183 precursor yielded a radical ion at m/z 124 as the base peak. The radical anion at m/z 124 was still the major fragment at all tested collision energies between 0 and 50 eV (E(lab)). Supported by computational studies, the appearance of the radical anion at m/z 124 as the major product ion can be attributed to the combination of a low reverse activation barrier and resonance stabilization of the product ions. Furthermore, our data lead to the proposal of a novel alternative radical formation pathway in the protection group removal of pyrogallol.

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