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1.
ACS Omega ; 4(18): 17672-17683, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31681873

RESUMO

In this work, we successfully prepared three different mesoporous NiO nanostructures with preferential (111) planes using three different solvents-water, a water-ethanol mixture, and a water-ethylene glycol mixture. The NiO nanosheets prepared from the water-ethylene glycol mixture and denoted as NiO-EG showed a nanosheet morphology thinner than 10 nm, whereas the water-ethanol and water samples were 30-40 nm and above 100 nm thick, respectively. The NiO-EG catalyst was found to exhibit a high catalyzing ability to activate peroxymonosulfate (PMS) for decoloring dyes, by which 94.4% of acid orange 7 (AO7) was degraded under the following reaction conditions: AO7 = 50 mg/L, catalyst = 0.2 g/L, PMS = 0.8 g/L, pH = 7, and 30 min reaction time. The dye degradation rate was investigated as a function of the catalyst dosage, pH, and dye concentration. According to quenching experiments, it was found that SO4 •-, HO•, and O2 •- were the dominant radicals for AO7 degradation, and oxygen vacancies played a significant role in the generation of radicals. High surface area, thin flaky structure, rich oxygen vacancies, fast charge transport, and low diffusion impedance all enhanced the catalytic activity of NiO-EG, which exhibited the highest degradation ability due to its abundant accessible active sites for both adsorption and catalysis.

2.
Materials (Basel) ; 12(16)2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398869

RESUMO

Wire and arc additive manufacturing based on cold metal transfer (WAAM-CMT) has aroused wide public concern in recent years as one of the most advanced technologies for manufacturing components with complex geometries. However, the microstructure and mechanical properties of the parts fabricated by WAAM-CMT technology mostly are intolerable for engineering application and should be improved necessarily. In this study, heat treatment was proposed to optimize the microstructure and enhance mechanical properties in the case of AlSi7Mg0.6 alloy. After heat treatment, the division between coarse grain zone and fine grain zone of as-deposited samples seemed to disappear and the distribution of Si and Mg elements was more uniform. What is more, the yield strength and ultimate tensile strength were improved significantly, while the ductility could be sustained after heat treatment. The improvement of strength is attributed to precipitation strengthening, and the shape change of Si phase. No reduction in ductility is due to the higher work hardening rate caused by nanostructured precipitate. It is proved that heat treatment as an effective method can control the microstructure and enhance comprehensive mechanical properties, which will boost rapid development of WAAM industrial technology.

3.
ACS Appl Mater Interfaces ; 11(34): 31009-31017, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31368295

RESUMO

Thermal conversion of CO2 to value-added chemicals is challenging due to the extreme inertness of the CO2 molecule and the low selectivity of products. We reported a defect-rich MgH2/CuxO hydrogen storage composite from mechanochemical ball-milling for the catalytic hydrogenation of CO2 to lower olefins. The defect-rich MgH2/CuxO hydrogen storage composite achieves a C2=-C4= selectivity of 54.8% and a CO2 conversion of 20.7% at 350 °C under a low H2/CO2 ratio of 1:5, which increases the efficiency of H2 utilization by offering lattice H- species for hydrogenation. Density functional theory calculations show that the defective structure of MgH2/CuxO can promote CO2 molecule adsorption and activation, while the electronic structure of MgH2 is beneficial for offering lattice H- for CO2 molecule hydrogenation. The lattice H- can combine the C site of CO2 molecule to promote the formation of Mg formate, which can be further hydrogenated to lower olefins under a low H- concentration. This work for CO2 conversion by a defect-rich MgH2/CuxO hydrogen storage composite can inspire the catalysts design for the hydrogenation of CO2 to lower olefins.

4.
Front Oncol ; 9: 630, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31428571

RESUMO

Castration Resistant Prostate Cancer (CRPC) is thought to be driven by a collaborative mechanism between TNFα/NFκB and TGFß signaling, leading to inflammation, Epithelial-to-Mesenchymal-Transition (EMT), and metastasis. Initially, TGFß is a tumor suppressor, but in advanced metastatic disease it switches to being a tumor promoter. TGFBR2 may play a critical role in this collaboration, as its expression is driven by NFκB and it is the primary receptor for TGFß. We have previously reported that the cardenolide drug digitoxin blocks TNFα/NFκB-driven proinflammatory signaling. We therefore hypothesized that digitoxin might break the collaborative process between NFκB and TGFß by also inhibiting expression of TGFBR2. We therefore tested whether TGFß-driven EMT and resulting metastases would be suppressed. Here we show, in vitro, that digitoxin inhibits NFκB-driven TGFBR2 expression, as well as Vimentin, while elevating E-cadherin expression. Digitoxin also significantly reduces HSPB1 mRNA and the HSPB1/RBFOX2 mRNA ratio in PC3 cells. In vivo, in a syngeneic, immune competent rat model of metastatic CRPC, we show that digitoxin also suppresses Tgfbr2 expression, as well as expression of other genes classically driven by NFκB, and of multiple EMT genes associated with metastasis. Concurrently, digitoxin suppresses tumor growth and metastasis in these animals, and prolongs survival. Gross tumor recurrence following tumor resection also appears prevented in ca 30% of cases. While the existence of a collaboration between NFκB and TGFß to drive EMT and metastasis has previously been appreciated, we show here, for the first time, that chronic, low concentrations of digitoxin are able to block CRPC tumor progression, EMT and the ensuing metastatic disease.

5.
Food Chem ; 274: 816-821, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30373015

RESUMO

Here, a facile, label-free and sensitive lateral flow strip (LFS) biosensor for foodborne pathogens was established relying on the innovative introduction of Gram staining and the direct immunoreaction. Target bacteria can be directly marked with crystal violet (CV) by one-step staining which is superior to traditional signal marking techniques in LFS assay, and the method's selectivity can be guaranteed by high-specificity monoclonal antibody. With Salmonella Enteritidis (S. Enteritidis) as a model target, this protocol can selectively detect 80 CFU mL-1S. Enteritidis within 11 min in the optimized conditions. Moreover, with Listeria monocytogenes as another model target, the biosensor shows a high universality for detections of both gram-negative and gram-positive bacteria. The unexpected applicability of biological dye tracer in strip biosensor reveals that the biological dye can be a potential tool serving as a universal signal tracer for pathogenic microorganisms in food safety monitoring and early clinical diagnosis.


Assuntos
Técnicas Biossensoriais/métodos , Microbiologia de Alimentos/métodos , Listeria monocytogenes/imunologia , Salmonella enteritidis/imunologia , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Água Potável/microbiologia , Inocuidade dos Alimentos/métodos , Violeta Genciana , Limite de Detecção , Lycopersicon esculentum/microbiologia , Fenazinas , Carne Vermelha/microbiologia
6.
Food Chem ; 270: 1-9, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30174021

RESUMO

Patulin (PAT) is one of the most common toxic contaminants of apple juice, which causes severe food safety issues throughout the apple industry. In order to remove PAT efficiently, a metal-organic framework-based adsorbent (UiO-66(NH2)@Au-Cys) was successfully synthesized and used for PAT removal from juice-pH simulation solution and real apple juice. Batch adsorption experiments were systematically performed to study the adsorption behavior for PAT. The results showed that adsorption process could be well described by the Pseudo-second order model and Freundlich isotherm model. The maximum adsorption capacity (4.38 µg/mg) was 10 times higher than the microbe-based biosorbents. Thermodynamic investigation demonstrated that adsorption process was spontaneous and endothermic. Furthermore, no marked cytotoxicity on NIH 3T3 cell lines was observed when the concentration of the adsorbent was lower than 10 µg/mL. Therefore, UiO-66(NH2)@Au-Cys is a potential adsorbent for PAT removal from apple juice with little quality changes.


Assuntos
Manipulação de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Malus/química , Patulina/química , Adsorção , Cisteína , Estruturas Metalorgânicas , Patulina/isolamento & purificação
7.
Waste Manag ; 82: 231-240, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30509585

RESUMO

Extremely high volatile fatty acids (VFAs) and ammonia concentrations can accumulate during dry co-digestion of organic wastes, which may inactivate pathogenic microorganisms. In this study, inactivation of Salmonella during dry co-digestion of pig manure (PM) and food waste (FW), which are both reservoirs of zoonotic pathogens, was examined. The effects of pH, VFAs, ammonia and their interactions were assessed on three inoculated Salmonella serotypes. The results show that dry co-digestion significantly decreased the Salmonella inactivation time from several months (in wet digestion) to as short as 6-7 days. A modified Weibull distribution was proposed to simulate Salmonella reduction and to calculate or predict the minimum inhibitory concentrations (MIC) of VFAs and ammonia. Statistical analysis showed that all the factors (pH, VFA type, VFA/ammonia concentration and Salmonella serotype) significantly impacted Salmonella inactivation (P < 0.01). The inhibitory effect sequence was pH > VFA concentration > VFA type > Salmonella serotype in VFA MIC tests, and ammonia concentration > pH > Salmonella serotype in ammonia MIC tests. The toxicity of VFAs was much greater than that of ammonia, and an antagonistic effect was found between VFAs and ammonia on Salmonella inactivation. Apart from the toxicity of free VFAs and free ammonia, the inhibitory effects of pH alone, ionized VFAs and ammonium were also observed.


Assuntos
Ácidos Graxos Voláteis , Esterco , Anaerobiose , Animais , Reatores Biológicos , Alimentos , Salmonella , Suínos
8.
Food Chem ; 261: 131-138, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-29739573

RESUMO

We presented a signal amplified lateral flow assay (LFA) based on magnetite nanoparticles (MNPs) labeled dual-probe and applied it in the high sensitive and rapid on-site detection of furazolidone metabolite of 3-amino-2-oxazolidinone (AOZ). The amplified signal benefited from high affinity between two probes of MNPs labeled murine monoclonal antibody (MNPs-MAb) and goat anti-mouse antibody (MNPs-GAMA) and was achieved by the generation of dual-probe network complex. This developed method could realize high sensitive detection of AOZ with a threshold value of 0.88 ng mL-1 and a detection limit of 0.044 ng mL-1, the sensitivity was at least 10-fold improved than that of the traditional gold nanoparticle based LFA. This facile developed assay was successfully applied for rapid detection of AOZ in milk samples. The proposed method paves a new way for on-site screening of other hazardous substances in food and can be referred in all lateral flow assays.


Assuntos
Análise de Alimentos/métodos , Furazolidona/análise , Nanopartículas de Magnetita/química , Leite/química , Animais , Furazolidona/química , Limite de Detecção , Oxazolidinonas/análise
9.
Sci Total Environ ; 631-632: 912-920, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29728002

RESUMO

Lead(II) is a highly toxic upon accumulation in the human body and a thorough cleanup of this pollutant in water resources has become a rising worldwide concern. In this study, multi-functional nitrogen-doped carbon-MoS2 (NC-MoS2) nanohybrid composite was successfully synthesized by a step-by-step approach and applied as an effective heavy metal ions adsorbent. Scanning electron microscopy and energy dispersive X-ray spectrometer analysis presents multilayer irregular nanosheets and reveals the uniform distribution of C, N and O elements in the fabricated nanomaterials, respectively. Powder X-ray diffraction, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirm the functionalization of oxygen-containing functional groups arising from the nitrogen-doped carbon. Particularly, the NC-MoS2 possesses an excellent adsorption capacity (439.09mgg-1) for Pb(II), which attributes to the integrated physicochemical adsorption resulting from the oxygen-containing functional groups on the surface of nanohybrid composites. The as-prepared NC-MoS2 exhibits good chemical stability and can be reused 7 times with a slight fading over 80% during cycling, which is essential for its practical applications. All of these demonstrate that NC-MoS2 can be an efficient material for selectively removal of Pb(II), which suggest its great potential in the utilization of environmental cleanup.


Assuntos
Carbono/química , Chumbo/química , Nitrogênio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Adsorção , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
10.
Food Chem ; 262: 48-55, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29751920

RESUMO

Immunochromatographic assays (ICAs) are most frequently used for on-site rapid screening of clenbuterol. To improve sensitivity, a novel probe with bacteria as signal carriers was developed. Bacteria can load a great deal of gold nanoparticles (AuNPs) on their surface, meaning much fewer antibodies are needed to produce clearly visible results, although low concentrations of antibody could also trigger fierce competition between free analyte and the immobilized antigen. Thus, a limited number of antibodies was key to significantly improved sensitivity. Analytical conditions, including bacterial species, coupling method, and concentration, were optimized. The visual detection limit (VDL) for clenbuterol was 0.1 ng/mL, a 20-fold improvement in sensitivity compared with traditional strips. This work has opened up a new route for signal amplification and improved performance of ICAs. Furthermore, inactivated bacteria could also be environment-friendly and robust signal carriers for other biosensors.


Assuntos
Técnicas Biossensoriais/métodos , Cromatografia de Afinidade/métodos , Clembuterol/análise , Escherichia coli , Nanopartículas Metálicas/química , Animais , Anticorpos/imunologia , Antígenos , Cromatografia de Afinidade/instrumentação , Feminino , Ouro/química , Limite de Detecção , Camundongos Endogâmicos BALB C , Sensibilidade e Especificidade
11.
Food Chem ; 256: 45-52, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29606471

RESUMO

Propyl gallate (PG), one of the most widely used synthetic phenolic antioxidants in edible oil, cookies and fried food, has received extensive concern due to its possible toxic effects on human health. Herein, a novel fluorescence analytical method is firstly proposed to sensitively and selectively determine propyl gallate (PG) by utilizing the unique fluorescence quenching property of organic molybdate complex (OMC) formed by the specific reaction between MoO42- and PG to g-C3N4 nanosheets. Under the optimum conditions, the developed fluorescence sensor allows highly sensitive detection of PG in a wide range from 0.5 to 200 µg mL-1 with a detection limit of 0.11 µg mL-1, and possesses excellent specificity and good recoveries. All the analytical results indicate the present method provides an effective approach for rapid detection of PG in common products, which is beneficial for monitoring and reducing the risk of overuse of PG.


Assuntos
Análise de Alimentos/métodos , Galato de Propila/análise , Espectrometria de Fluorescência/métodos , Antioxidantes/análise , Complexos de Coordenação/química , Humanos , Limite de Detecção , Molibdênio/química , Nanoestruturas/química
12.
Food Chem ; 257: 155-162, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29622193

RESUMO

In order to develop an accurate and precise determination method based on solid phase extraction of Pb(II) in food and water samples, a hybrid monolithic column based on layered double hydroxides (LDHs) nanosheets-alginate hydrogel has been synthesized. Combining the advantages of porous 3D framework of hydrogel with selective adsorption of LDHs toward Pb(II), the hydrogel-based hybrid monolithic column shows enhanced enrichment selectivity and efficiency for target ions. Effects of hydrogel composition, pH, concentration and type of eluent, sample volume, and interfering ions on the recoveries of the analytes were also investigated. Under the optimal experiment conditions of method, the limit of detection, preconcentration factor and precision as RSD% are found to be 0.39 µg L-1, 53.7 and 2.65%, respectively. Trace Pb(II) can be quantitatively preconcentrated at pH 6.0 with recoveries >97%. Finally, the method was successfully verified by analyzing spiked Pb2+ in water and drinking samples.


Assuntos
Alginatos/química , Alimentos , Hidrogéis/química , Hidróxidos/química , Chumbo/isolamento & purificação , Extração em Fase Sólida/métodos , Água/química , Adsorção , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Chumbo/análise , Chumbo/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
13.
Inorg Chem ; 57(9): 5560-5566, 2018 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-29634244

RESUMO

We have demonstrated that natural sugars can efficiently exfoliate inorganic layered nanomaterials with direct stirring. The representative transition-metal dichalcogenides (MoS2 and WS2), transition-metal oxide (MoO3), and graphene were explored, and the formation of ultrathin nanosheets was verified. Glucose and MoS2 selected each other as the perfect partner with superior exfoliation and excellent properties. The obtained inorganic layered nanosheets possess favorable stability and dispersity, which renders it suitable for direct homogeneous liquid applications, such as catalytic activities and sensors. With a high-throughput and green process, the sugar-assisted method may offer new ideas for inorganic layered nanomaterials synthesis and applications in a more ecofriendly way.

14.
Food Chem ; 254: 241-248, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29548448

RESUMO

UiO-67, a bifunctional adsorbent, was successfully applied to remove illegal food dyes (Congo red and Malachite green) from aqueous solution. The relevant adsorption conditions were optimized: pH 6, 120 min for contact time, and 10.0 mg L-1 adsorbent dose for Congo red. Adsorption behavior of UiO-67 exhibits a better fitting to pseudo-second-order kinetic model and Langmuir model. Moreover, the maximum adsorption capacities of Congo red (1236.9 mg g-1) and Malachite green (357.3 mg g-1) are higher than that of the most reported adsorbents. Thermodynamic analysis reveals that adsorption processes are spontaneous and endothermic in nature. Powder X-ray diffraction patterns, Fourier-transform infrared spectra and the X-ray photoelectron spectroscopy analysis indicates Zr-OH groups have positive influence on binding of target molecules. What's more, UiO-67 could be reused without significant loss of its capacity after seven cycles. These results prefigure the promising potentials of UiO-67 in food safety risk management.


Assuntos
Vermelho Congo/isolamento & purificação , Corantes de Alimentos/isolamento & purificação , Contaminação de Alimentos , Estruturas Metalorgânicas/química , Corantes de Rosanilina/isolamento & purificação , Adsorção , Vermelho Congo/química , Corantes de Alimentos/química , Cinética , Espectroscopia Fotoeletrônica , Corantes de Rosanilina/química , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Água/química , Difração de Raios X , Zircônio/química
15.
Nat Commun ; 9(1): 734, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29467414

RESUMO

Phosphorescence shows great potential for application in bioimaging and ion detection because of its long-lived luminescence and high signal-to-noise ratio, but establishing phosphorescence emission in aqueous environments remains a challenge. Herein, we present a general design strategy that effectively promotes phosphorescence by utilising water molecules to construct hydrogen-bonded networks between carbon dots (CDs) and cyanuric acid (CA). Interestingly, water molecules not only cause no phosphorescence quenching but also greatly enhance the phosphorescence emission. This enhancement behaviour can be explained by the fact that the highly ordered bound water on the CA particle surface can construct robust bridge-like hydrogen-bonded networks between the CDs and CA, which not only effectively rigidifies the C=O bonds of the CDs but also greatly enhances the rigidity of the entire system. In addition, the CD-CA suspension exhibits a high phosphorescence lifetime (687 ms) and is successfully applied in ion detection based on its visible phosphorescence.

16.
Oncotarget ; 9(7): 7557-7566, 2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29484132

RESUMO

This study aimed to explore the efficacy and safety of drug-eluting bead (DEB) embolization (DEB-TACE) when combined with cryoablation in the treatment of unresectable hepatocellular carcinoma (HCC). The study was a single-center randomized controlled trial comprised of 60 patients with HCC conducted between August 2015 and October 2017. The patients were randomly divided into two groups: DEB-TACE combined with cryoablation (DEB-TACE-Cryo group) or cryoablation alone (Cryo group). Inter-group differences in overall survival, progression-free survival, and adverse reactions were assessed. The operative success rates were 82.7% and 77.4% in the DEB-TACE-Cryo group and Cryo group, respectively, with no operative mortality. The overall survival and progression-free survival in the DEB-TACE-Cryo group were significantly higher than those in the Cryo group (16.8 months vs.13.4 months, P = 0.0493; 8.1 months vs. 6.0 months, P = 0.0089, respectively). The postoperative complications in the two groups were rated as grade 1 or grade 2, according to guidelines set by the National Cancer Institute Common Terminology Criteria for Adverse Events Version 4.0 (CTCAE V4.0). We demonstrated that DEB-TACE combined with cryoablation was effective, well tolerated, and had a low complication rate. Therefore, this combination therapy may be a better choice for the treatment of unresectable hepatocellular carcinoma.

17.
ACS Appl Mater Interfaces ; 9(21): 18170-18177, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28485133

RESUMO

A series of ordered mesoporous chromium oxides (Cr2O3) were synthesized by first replicating bicontinuous cubic Ia3d mesoporous silica (KIT-6), then a controlled mesostructural transformation from Ia3d to I4132 symmetry during the replication from KIT-6 to Cr2O3 was achieved by reducing the pore size and interconnectivities of KIT-6, accompanied with an increase in pore size from 3 to 12 nm and a decrease in framework thickness from 8.6 to 5 nm of the resultant Cr2O3 replicas. The gas-sensing behavior of the Cr2O3 replicas toward formaldehyde (HCHO) was systematically investigated. Ordered mesoporous Cr2O3 with both large accessible pores (12 nm) and an ultrathin framework (5 nm) exhibits the best sensing performance, with a response (Rgas/Rair = 119) toward 9 ppm of HCHO 4.4 times higher than that (Rgas/Rair = 27) of its counterpart with small pores and a thick framework. Moreover, it possesses excellent selectivity for detecting HCHO over other interference gases such as CO, benzene, toluene, p-xylene, NH3, H2S, and moisture. The significantly enhanced sensing performance of ordered large-pore mesoporous Cr2O3 with ultrathin framework suggests its great potential for the selective detection of HCHO.

18.
Mikrochim Acta ; 185(1): 7, 2017 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-29594417

RESUMO

The authors have discovered that vanadium disulfide (VS2) nanosheets, synthesized by a hydrothermal method, exert stable peroxidase-like activity. The catalytic activity, with H2O2 as a cosubstrate, follows Michaelis-Menten kinetics and varies with temperature, pH value and H2O2 concentration. Two-dimensional VS2 sheets acting as peroxidase (POx) mimics can replace horseradish peroxidase due to their availability, robustness, and reusability. The POx-like activity of VS2 sheets was exploited to design a colorimetric glucose assay by using 3,3',5,5'-tetramethylbenzidine as a substrate and by working at an analytical wavelength of 652 nm. The assay covers the 5 to 250 µM glucose concentration range with a 1.5 µM detection limit. It was applied to the analysis of glucose in fruit juice. In our perception, the peroxidase-like nanozyme out of the family of transition metal dichalcogenides presented here has a wide scope in that it may stimulate promising biocatalytic applications in biotechnology and analytical chemistry. Graphical abstract Layered VS2 nanosheets were prepared via hydrothermal synthesis and are shown to exert superior peroxidase-mimicking activity. Using these POx nano-mimics, a sensitive colorimetric assay for glucose was developed and applied to fruit juice analysis. This work unlocks the access of VS2 to biocatalysis and bioassays.


Assuntos
Colorimetria/métodos , Glucose/análise , Peroxidase do Rábano Silvestre/química , Nanopartículas Metálicas/química , Compostos de Vanádio/química , Benzidinas/química , Biocatálise , Materiais Biomiméticos/química , Técnicas Biossensoriais/métodos , Peróxido de Hidrogênio/química , Cinética , Limite de Detecção , Oxirredução
19.
Cell Physiol Biochem ; 40(5): 1063-1078, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27960153

RESUMO

BACKGROUND/AIMS: Chronic lung infection in cystic fibrosis leads to an inflammatory response that persists because of the chronic presence of bacteria and ultimately leads to a catastrophic failure of lung function. METHODS: We use a combination of biochemistry, cell and molecular biology to study the interaction of TRADD, a key adaptor molecule in TNFα signaling, with CFTR in the regulation of NFκB. RESULTS: We show that Wt CFTR binds to and colocalizes with TRADD. TRADD is a key signaling intermediate connecting TNFα with activation of NFκB. By contrast, ΔF508 CFTR does not bind to TRADD. NF-κB activation is higher in CFBE expressing ΔF508 CFTR than in cells expressing Wt CFTR. However, this differential effect is abolished when TRADD levels are knocked down. Transfecting Wt CFTR into CFBE cells reduces NF-κB activity. However the reduction is abolished by the CFTR chloride transport inhibitor-172. Consistently, transfecting in the correctly trafficked CFTR conduction mutants G551D or S341A also fail to reduce NFκB activity. Thus CFTR must be functional if it is to regulate NF-κB activity. We also found that TNFα produced a greater increase in NF-κB activity in CFBE cells than in the same cell when Wt CFTR-corrected. Consistently, the effect is also abolished when TRADD is knocked down by shRNA. Thus, Wt CFTR control of TRADD modulates the physiological activation of NF-κB by TNFα. Based on studies with proteosomal and lysosomal inhibitors, the mechanism by which Wt CFTR, but not ΔF508 CFTR, suppresses TRADD is by lysosomal degradation. CONCLUSION: We have uncovered a novel mechanism whereby Wt CFTR regulates TNFα signaling by enhancing TRADD degradation. Thus by reducing the levels of TRADD, Wt CFTR suppresses downstream proinflammatory NFκB signaling. By contrast, suppression of NF-κB activation fails in CF cells expressing ΔF508 CFTR.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , NF-kappa B/metabolismo , Proteólise , Proteína de Domínio de Morte Associada a Receptor de TNF/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Células HEK293 , Humanos , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras , Ligação Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Fatores de Tempo , Fator de Necrose Tumoral alfa/farmacologia
20.
Chin J Integr Med ; 22(9): 653-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27614450

RESUMO

OBJECTIVE: To evaluate the long-term clinical effect of Tangyiping Granules (, TYP) on patients with impaired glucose tolerance (IGT) to achieve normal glucose tolerance (NGT) and hence preventing them from conversion to diabetes mellitus (DM). METHODS: In total, 127 participants with IGT were randomly assigned to the control (63 cases, 3 lost to follow-up) and treatment groups (64 cases, 4 lost to follow-up) according to the random number table. The control group received lifestyle intervention alone, while the patients in the treatment group took orally 10 g of TYP twice daily in addition to lifestyle intervention for 12 weeks. The rates of patients achieving NGT or experiencing conversion to DM as main outcome measure were observed at 3, 12, and 24 months after TYP treatment. The secondary outcome measures included fasting plasma glucose (FPG), 2-h postprandial plasma glucose (2hPG), glycosylated hemoglobin (HbA1c), fasting insulin (FINS), 2-h insulin (2hINS), homeostatic model assessment of insulin resistance (HOMA-IR), blood lipid and patients' complains of Chinese medicine (CM) symptoms before and after treatment. RESULTS: A higher proportion of the treatment group achieved NGT compared with the control group after 3-, 12- and 24-month follow-up (75.00% vs. 43.33%, 58.33% vs. 35.00%, 46.67% vs. 26.67%, respectively, P<0.05). The IGT to DM conversion rate of the treatment group was significantly lower than that of the control group at the end of 24-month follow-up (16.67% vs. 31.67%, P<0.05). Before treatment, FPG, 2hPG, HbA1c, FINS, 2hINS, HOMA-IR, triglyceride (TG), total cholesterol, low- and high-density lipoprotein cholesterol levels had no statistical difference between the two groups (P>0.05). After treatment, the 2hPG, HbA1c, HOMA-IR, and TG levels of the treatment group decreased significantly compared with those of the control group (P<0.05). CM symptoms such as exhaustion, irritability, chest tightness and breathless, spontaneous sweating, constipation, and dark thick and greasy tongue were significantly improved in the treatment group as compared with the control group (P<0.05). No severe adverse events occurred. CONCLUSION: TYP administered at the IGT stage with a disciplined lifestyle delayed IGT developing into type 2 DM.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Intolerância à Glucose/tratamento farmacológico , Glicemia/metabolismo , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Feminino , Intolerância à Glucose/sangue , Humanos , Insulina/sangue , Rim/efeitos dos fármacos , Rim/fisiopatologia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
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