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1.
Chemistry ; 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32027761

RESUMO

Heterogeneously catalyzed selective hydrogenation in the liquid phase is widely used in industry for the synthesis of chemicals. However, it can be a challenge to prevent active nanoparticles ( e.g.  Pd) from aggregation/leaching, and meanwhile, to achieve a high conversion as well as selectivity, especially under a mild condition. To address these issues, CeO 2  nanotube/Pd@MIL-53(Al) sandwich structured catalyst is prepared, in which the MIL-53(Al) porous shell can efficiently stabilize Pd nanoparticles. When this kind of catalyst is used in the tandem catalytic reactions between the dehydrogenation of ammonia borane and the phenylacetylene hydrogenation, remarkably, the in-situ released hydrogen species from the dehydrogenation of ammonia borane boosts the catalysis process with 100 % phenylacetylene conversion and the selectivity of 96.2 % for styrene, even under the room temperature and atmospheric pressure within 1 min. This work provides an alternative strategy to balance the conversion and selectivity in liquid-phase hydrogenation reactions.

2.
Waste Manag ; 105: 8-17, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32007733

RESUMO

When it comes to the combustion of biomass, per ton of solid biofuel will generate 70 kg ash on average. Additionally, these ashes have a high specific surface area, especially fly ash, which may adsorb harmful substances and damage to human health. This work was aimed to reutilize biomass power plant fly ash to produce silica material, to reduce the hazard of ash landfill for environment. The ash underwent acid leaching with 1.5 M HCl after proper heating pre-treatment. Then, 2 M NaOH was direct to react with residue to obtain sodium silicate. Finally, acid titration of solution was used to precipitate silica. The results showed that the amorphous silica has been produced from fly ash successfully with the purity from 44.41% to 93.63% and yield of 20.45%, and the optimal calcination conditions for amorphous transformation of silica in fly ash were temperature of 611 °C with time of 5 h and the minimum crystallinity was 17.41%, modeled with response surface methodology. Spectroscopy analysis revealed that the three-dimensional network silica was hydroxylated to form the linear structure. Thermal analysis indicated that the decomposition of silanol groups tend to be stable at 400 °C, but the ash was decomposing up to 1000 °C. Morphological analysis demonstrated that BET surface area ranged from 24 m2/g to 115 m2/g, agglomerate particle size from 380.9 nm to 178.8 nm, when the ash was conversion to spherical silica. Consequently, it is possible to turn blend biomass fly ash into amorphous silica nanoparticles.

3.
Bioresour Technol ; 304: 123002, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32078904

RESUMO

This study studied the change of functionalities in the biochar formed in pyrolysis of poplar wood in a wide range of temperature. The in situ Diffuse Reflectance Infrared Fourier transform spectroscopy characterization indicated that aldehydes and ketones functionalities formation initiated at 100 °C, dominated at 300 to 500 °C. Carboxyl group was less stable than carbonyls. Cellulose crystal in poplar decomposed slightly at 300 °C and significantly at 350 °C. The temperature from 250 to 350 °C significantly affected biochar yields, while the drastic fusion of the ring structures in biochar occurred from 550 to 650 °C, making biochar more aliphatic while less more aromatic. High pyrolysis temperature also created more defective structures in the biochar and favored the absorption of the CO2 generated during the pyrolysis. The results provide the reference information for understanding the structural configuration and evolution of the functionalities during in pyrolysis of poplar biomass.

4.
Phys Chem Chem Phys ; 22(7): 3953-3958, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32020137

RESUMO

The reduction of ZnO in a ZnO-supported catalyst to metallic zinc, the alloying of metallic zinc with a second metal and the evaporation of zinc species in a reductive atmosphere of hydrogen was investigated in this study. The results show that the reduction temperature was the determining factor for the transformation of zinc species. The complete removal of ZnO in a ZnO-supported catalyst can be achieved at 700 °C. The effects of different metals supported on ZnO on the transformation of ZnO were also investigated. Cu, Co and Ni species can slow the ZnO loss due to the priority for the reduction of these metal oxides and the formation of metal-Zn intermetallics. Fe based catalysts noticeably accelerated the loss of ZnO, which can be ascribed to the high oxophilicity of Fe and the strong interactions between the metal and support.

5.
ACS Appl Mater Interfaces ; 12(4): 4833-4842, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31914316

RESUMO

Development of low-cost and efficient (electro)catalysts with tunable 2e/4e oxygen reduction reaction (ORR) selectivity toward energy conversion, biomimetic catalysis, and biosensing has attracted growing interest. Herein, we reported that carbon nanohybrids with O- or N-coordinated Cu (Cu-OC or Cu-NC) showed superior activity for 2e and 4e electrocatalytic ORR with selectivities of 84.0% and 97.2%, respectively. Experimental evidence demonstrated that the strong electron-rich O-doped carbon in Cu-OC donated electrons to Cu2+, weakening the binding strength of H2O2 at Cu-O centers and facilitating the 2e ORR pathway for selective production of H2O2. However, the poor electron-donor ability of the N-doped carbon in Cu-NC made Cu-N sites more electron deficient due to the reduced electron transfer from N-doped carbon to Cu2+, promoting 4e ORR by enhancing adsorption of O2 and the ORR intermediates. The high 4e ORR activity of Cu-NC rendered its potential for application in a Zn-air battery and oxidase-mimicking activity for 3,3',5,5'-tetramethylbenzidine (TMB) and ascorbic acid (AA) oxidation. The maximal velocity (Vmax) of TMB and AA oxidation over Cu-NC was higher than some natural oxidases and noble-metal-based artificial enzymes. The lower activation energy for AA oxidation over Cu-NC resulted in a 263-fold higher oxidative rate than TMB, further prompting nonenzymatic sensing of AA by the competitive oxidation strategy.

6.
Int Heart J ; 61(1): 67-76, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31956151

RESUMO

Pre-procedural serum albumin's impact on prognosis after transcatheter aortic valve replacement (TAVR) has been studied. Literature on the prognostic role of serum albumin in the survival of patients undergoing TAVR shows conflicting results. This meta-analysis was conducted to evaluate the impact of pre-procedural serum albumin on outcomes after TAVR. A comprehensive literature search of EMBASE, MEDLINE, and the Cochrane Library was undertaken through July 2019. The primary end points were 30-day and one-year all-cause mortality after TAVR. Risk ratios (HRs) and 95% confidence intervals (CIs) were calculated using the random-effect model. Ten eligible studies with 8,236 patients were analyzed. Of the 8,236 patients undergoing TAVR, with a mean age of 83 years, 48.8% were men and were categorized into two groups according to low and normal serum albumin (cut-off value: 3.5 or 4 g/dL). Overall, low albumin was significantly associated with an approximately two-fold increase in 30-day all-cause mortality (HR, 2.09; 95% CI, 1.53-2.86) and a 61% increase risk for one-year mortality (HR, 1.61; 95% CI, 1.31-1.98) in patients after TAVR. Sensitivity analyses showed the results to be robust. The association of low albumin level with an increase in one-year mortality risk was not modified by study design, albumin cut-off value, Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM), and study quality. In conclusion, low albumin levels were associated with poor prognosis in patients after TAVR. Pre-procedural albumin can be used as a simple tool related to prognosis after TAVR.


Assuntos
Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/cirurgia , Albumina Sérica/metabolismo , Substituição da Valva Aórtica Transcateter/métodos , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/metabolismo , Regulação para Baixo , Feminino , Humanos , Masculino , Razão de Chances , Prognóstico , Resultado do Tratamento
7.
Biosens Bioelectron ; 150: 111910, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31784312

RESUMO

To sensitively detect cardiac troponin I (cTnI), a novel electrochemiluminescence (ECL) immunosensor was constructed on the basis of the core-shell Mo2C combined with carbon material (Mo2C@C) nanosphere as an ECL super-enhancer and a label of secondary antibody (Ab2). Mo2C@C nanosphere with excellent conductivity and high chemical stability could increase the ECL intensity of the tris-(2,2'-bipyridine)ruthenium (Ru(bpy)32+). Mo2C@C/polyethylenimine (Mo2C@C/PEI) firmly anchored Ab2 by covalent bonding. Otherwise, amino-modified multiwall carbon nanotubes@nafion (MWCNTs-NH2@N) composite film, as substrate material, could connect with the Ru(bpy)32+ by ion exchange and immobilize primary antibodies (Ab1) by amide bond. In addition, the boron nitride quantum dots (BNQDs) were utilized as the co-reactant, which were synthesized by using low-cost material melamine as a nitrogen source. Under optimal experimental conditions, the proposed ECL immunosensor possessed a low detection limit of 0.03 pg/mL (S/N = 3) and a wide linear range from 0.1 pg/mL to 50 ng/mL. The ultrasensitive ECL immunosensor had excellent stability, outstanding specificity and great reproducibility. It was also used to detect cTnI in human serum with satisfactory results.

8.
J Hazard Mater ; 385: 121527, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31708287

RESUMO

Regulation of defects and surface acidic sites of photocatalysts is an efficient approach to improve the photocatalytic activity. Ultrathin 2D-ZnO photocatalysts were prepared to uncover the synergetic effects of defects and surface acidic sites on the photocatalytic activity. The reaction constant for photocatalytic degradation of MB upon ZnO-S is 2.26, 2.82, 12.2 times higher than that of SH-500, SO-500, and ZnO-R, respectively. The results revealed that the surface defects, hydroxyl group and chemisorbed water played pivotal roles in the generation of reactive oxygen species (ROS). Although the limited improvement of visible absorption was achieved after introduction of oxygen vacancy (VO), the overall photocatalytic activity decreased due to the reduced ROS production capacity shown by density functional theory (DFT) calculations. Hydroxyl radical is the key ROS in degradation of organics, and electron contributes a little bigger than hole in the generation of hydroxyl radical. Importantly, the decrease in surface acidic sites resulted in the decreased photocatalytic activity, proven by the dynamics of photoinduced carriers. This study reveals that the improved photocatalytic activity of 2D-ZnO photocatalysts can be attributed to the synergetic effects of surface defects and acidic sites rather than the enhanced visible absorption resulted from the VO introduction.

9.
J Hazard Mater ; 385: 121550, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31732338

RESUMO

In this study, ordered mesoporous carbon (OMC) was synthesized by applying a soft template method, and its mesoporous structure was characterized by scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption-desorption techniques. X-ray diffraction and Raman spectroscopic analyses were conducted to demonstrate the high graphitization and topological defects at the sample surface. An electrochemical sensor based on an OMC-modified glassy carbon electrode (OMC/GCE) was constructed to detect aristolochic acids (AAs) using cyclic voltammetry and linear sweep voltammetry. The dependence of the experimental parameters including solution pH, scan rate, and accumulation time were examined and optimized. Under the optimal conditions, the response of OMC/GCE was linear over wide concentration ranges of AAs (0.6-10 µM and 10-50 µM), with sensitivities of -1.77 and -0.31 µA/µM, respectively. The limit of detection was calculated to be 0.186 µM (at S/N = 3). Furthermore, the proposed OMC/GCE was applied to detect AAs in Asarum sieboldini and the content of AAs was calculated to be 8.9 µg/g with high accuracy and precision. In addition, the modified electrode also exhibited good selectivity, reproducibility, and stability. Therefore, the OMC/GCE can be used as a platform for the determination of AAs.

10.
J Ethnopharmacol ; 247: 112283, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31605736

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bulbus Fritillaria cirrhosa D. Don (BFC) is a Chinese traditional herbal medicine that has long been used as an indispensable component in herbal prescriptions for bronchopulmonary diseases due to its well-established strong anti-inflammation and pulmonary harmonizing effects. Interestingly, there are few case reports in traditional Chinese medicine available where they found it to contribute in anti-tumor therapies. Imperialine is one of the most favored active substances extracted from BFC and has been widely recognized as an anti-inflammatory agent. AIM OF THE STUDY: The aim of the current work is to provide first-hand evidences both in vitro and in vivo showing that imperialine exerts anti-cancer effects against non-small cell lung cancer (NSCLC), and to explore the molecular mechanism of this anti-tumor activity. It is also necessary to examine its systemic toxicity, and to investigate how to develop strategies for feasible clinical translation of imperialine. MATERIALS AND METHODS: To investigate anti-NSCLC efficacy of imperialine using both in vitro and in vivo methods where A549 cell line were chosen as in vitro model NSCLC cells and A549 tumor-bearing mouse model was constructed for in vivo study. The detailed underlying anti-cancer mechanism has been systematically explored for the first time through a comprehensive set of molecular biology methods mainly including immunohistochemistry, western blot and enzyme-linked immunosorbent assays. The toxicity profile of imperialine treatments were evaluated using healthy nude mice by examining hemogram and histopathology. An imperialine-loaded liposomal drug delivery system was developed using thin film hydration method to evaluate target specific delivery. RESULTS: The results showed that imperialine could suppress both NSCLC tumor and associated inflammation through an inflammation-cancer feedback loop in which NF-κB activity was dramatically inhibited by imperialine. The NSCLC-targeting liposomal system was successfully developed for targeted drug delivery. The developed platform could favorably enhance imperialine cellular uptake and in vivo accumulation at tumor sites, thus improving overall anti-tumor effect. The toxicity assays revealed imperialine treatments did not significantly disturb blood cell counts in mice or exert any significant damage to the main organs. CONCLUSIONS: Imperialine exerts anti-cancer effects against NSCLC both in vitro and in vivo, and this previously unknown function is related to NF-κB centered inflammation-cancer feedback loop. Imperialine mediated anti-cancer activity is not through cytotoxicity and exhibit robust systemic safety. Furthermore, the liposome-based system we commenced would dramatically enhance therapeutic effects of imperialine while exhibiting extremely low side effects both on cellular and in NSCLC model. This work has identified imperialine as a promising novel anti-cancer compound and offered an efficient target-delivery solution that greatly facilitate practical use of imperialine.

11.
Sci Total Environ ; 699: 134381, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31677466

RESUMO

This study investigated the pyrolysis of lignin pyrolysis in a temperature region from 200 to 800 °C, aiming to understand influence of pyrolysis temperature on evolution of structures of the resulting char. The results showed that fusion of the ring structure initiated at 200 °C, where the C/H ratio in the char was equal to that in naphthalene (two fused rings). The C/H ratio in the char obtained at 350 °C corresponded to that in pyrene (four fused rings), while the char produced at 550 °C was equivalent to 20 fused benzene rings in terms of C/H ratio. The increasing pyrolysis temperature also shifted the oxygen-containing functionalities such as the carbonyl, esters, ketones in the bio-oil to the ether functionality that had a higher thermal stability. The DRIFTS study of pyrolysis of lignin showed that drastic changes of the functionalities and the internal structure of the char occurred in a narrow temperature region from 520 to 530 °C. The carbonyl functionality and the aliphatic structure were eliminated, and new conjugated π-bond systems formed.


Assuntos
Carvão Vegetal/química , Lignina/química , Pirólise , Temperatura Ambiente , Biocombustíveis , Biomassa , Temperatura Alta
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(6): 867-871, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31880119

RESUMO

OBJECTIVE: To explore the effect of smoking on the histological subtype and prognosis of patients with lung adenocarcinoma (LAC) in China. METHODS: According to the new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society(IASLC/ATS/ERS)classification, 266 donors with primary LAC were reclassified. The correlation between clinicopathological factors including smoking status and the histological subtype was analyzed, and survival analysis was used to analyze the prognosis of primary LAC. RESULTS: There were four main histological subtypes including acinar predominant adenocarcinoma (APA) 30.1%, papillary predominant adenocarcinoma (PPA) 26.7%, solid predominant adenocarcinoma (SPA) 25.9%, and lepidic predominant adenocarcinoma (LPA) 11.7%.Smoking was associated with the histological subtype.The proportion of smokers was significantly higher than non-smokers in the SPA group, and the proportion of non-smokers was higher in other subtypes group. Cox regression model showed that the histological subtype and TNM stage were the independent predictors of prognostic in all patients.TNM stage was the predictor of postoperative survival in both smokers and non-smokers, and histological subtypes was the predictor only in smokers (ß=0.898, RR=2.455). Compared with the non-SPA group, the prognosis of the SPA group was significantly worse. CONCLUSION: Smoking is associated with SPA subtype, which affect the prognosis of primary LAC.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Fumar , China , Humanos , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos
13.
ChemSusChem ; 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31846205

RESUMO

Developing highly active nonprecious-metal catalysts for the oxygen reduction reaction (ORR) is of great significance for reducing the cost of fuel cells. 3D-ordered porous structures could substantially improve the performance of the catalysts because of their excellent mass-diffusion properties and high specific surface areas. Herein, ordered porous ZIF-67 was prepared by forced molding of a polystyrene template, and Co-supported, N-doped, 3D-ordered porous carbon (Co-NOPC) was obtained after further carbonization. Co-NOPC exhibited excellent performance for the ORR in an alkaline medium with a half-wave potential of 0.86 V vs. reversible hydrogen electrode (RHE), which is higher than that of the state-of-the-art Pt/C (0.85 V vs. RHE). Moreover, the substantially improved catalytic performance of Co-NOPC compared with Co-supported, N-doped carbon revealed the key role of its hierarchical porosity in boosting the ORR. Co-NOPC also exhibited a close-to-ideal four-electron transfer path, long-term durability, and resistance to methanol penetration, which make it promising for large-scale application.

14.
Clin Cardiol ; 42(12): 1170-1180, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31609463

RESUMO

BACKGROUND: Dual antiplatelet therapy (DAPT) in the form of aspirin plus a P2 Y12 inhibitor, when indicated, is one of the key treatments in coronary artery disease (CAD). Many recommendations on DAPT in patients with CAD based on current guidelines are largely inconsistent. In our current study, we aimed at systematically reviewing DAPT-relevant clinical practice guidelines, and highlighting their commonalities and differences for better informed decision-making. METHODS: Contemporary guidelines in English were searched in MEDLINE, Embase and websites of guideline organizations and professional societies. Guidelines with recommendations on DAPT for CAD patients were included. Guideline quality was appraised with the 6-domain Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument. The reporting of conflicts of interest (COI) was assessed individually with supplementary items from the RIGHT (Reporting Item for Practice Guidelines in Healthcare) checklist. Meanwhile, extraction of recommendations was performed. RESULTS: A total of 18 guidelines fulfilled our inclusion criteria. Most of them were graded with relatively good scores averaging from 42% to 74%. Domains for lower scores were in "stakeholder involvement" and "application." The reporting of COI was satisfactory. For the recommendations on DAPT, most guidelines with high AGREE II scores included consistent recommendations on the timing and P2 Y12 inhibitor selection. Nonetheless, conflicts still exist on the duration of DAPT. CONCLUSIONS: Quality of guidelines for DAPT in CAD was relatively high, though defects existed in "Applicability" and "Stakeholder Involvement." As these guidelines developed, DAPT recommendations gradually converged on a consensus. Clinical decision should be made on an individual basis.

16.
J Thorac Dis ; 11(8): 3534-3546, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31559060

RESUMO

Background: Clinical practice guidelines (CPGs) provide many recommendations for hyperlipidemia management, but some of them are still debatable. Methods: We applied the six-domain Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument to evaluate the quality of guidelines with lipid management recommendations for coronary heart disease (CHD), including dyslipidemia and CHD guidelines published from 2009 to 2019. Meanwhile, we synthesized and compared major recommendations and present the consistency and controversy in current dyslipidemia management. Results: Among 19 guidelines included, ten guidelines ("strongly recommended" with AGREE scores 61-94%) performed better than the other nine (38-65% as "recommended with some modification") For blood lipid tests, most CHD guidelines simply required fasting sample while dyslipidemia guidelines preferred non-fasting sample except in high triglycerides state. Most guidelines consistently chose low-density lipoprotein cholesterol (LDL-C) as the primary lipid-lowering target (LLT), while non-high-density lipoprotein cholesterol (non-HDL-C) and apolipoprotein B were mainly selected as secondary LLTs. The specific goals of LDL-C lowering were either to lower than 70 mg/dL or with at least 50% reduction. All guidelines recommended high intensity or maximally tolerable doses of statins, while ezetimibe and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors were recommended as second-line therapy. Conclusions: The general quality of guidelines for lipid management is satisfactory. Consensus has been reached on the specific goal of lipid reduction and the intensity of statins therapy. Further research is needed to validate the application of non-fasting sample and non-HDL-C target, as well as the efficacy and safety of ezetimibe and PCSK9 inhibitors.

17.
Compr Psychiatry ; 94: 152114, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401216

RESUMO

BACKGROUND: Promising biomarkers would be used to improve the determination of diagnosis and severity, as well as the prediction of symptomatic and functional outcomes of schizophrenia. BASIC PROCEDURES: In this study, we used three different mouse models induced by a genetic factor (PV-Cre; ErbB4-/-, G group), an environmental stressor (adolescent social isolation, G group), and a combination of genetic factor and environmental stressor (PV-Cre; ErbB4-/- mice with isolation, G × E group). Attenuated PPI (%) confirmed the successful establishment of three schizophrenia-like mouse models. To evaluate whether neuropeptide levels in plasma would be potential biomarkers of different schizophrenia models in our work, we used MILLIPLEX® MAP method to simultaneously measure 6 critical neuropeptides in plasma. MAIN FINDINGS: Among the evaluated neuropeptides, increased neurotensin tends to be associated with genetic factors of schizophrenia, increased orexin A seems to be a biomarker of an interplay between genetic and social isolation, while higher plasma oxytocin might be more apt to be responsive to social isolation. The potential biomarkers are mostly independent of sex. CONCLUSIONS: This research would provide novel clues to develop circulating biomarkers of plasma neuropeptides for multifactorial schizophrenia.

18.
Nanoscale ; 11(35): 16293-16298, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31465063

RESUMO

An atomically-precise silver(i)-cluster-based three-dimensional (3D) framework (UJN-1) stabilized by a ditiocarb (diethyldithiocarbamate) ligand has been unveiled for the first time by self-assembly. UJN-1 is composed of both Ag9 clusters and Ag5 subunits, of which the Ag9 clusters are bonded with Ag5 subunits by sharing the ditiocarb ligand to form a microporous 3,4-connected topological framework. The chemically reduced nano-sized derivative of UJN-1 exhibits highly sensitive surface enhanced Raman scattering (SERS) towards 4-mercaptobenzoic acid (4-MBA) signal molecules, which is ascribed to the porosity as well as the distribution of abundant crystalline Ag0 active sites. This work sheds light on a new bottom-up approach to construct SERS-active silver(i)-cluster-based 3D materials by disulfur ligand stabilization.

19.
Stem Cell Res Ther ; 10(1): 263, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31443679

RESUMO

BACKGROUND: Myocardial fibrosis is a common pathophysiological change in cardiovascular disease, which can cause cardiac dysfunction and even sudden death. Excessively activated fibroblasts proliferate and secret excessive extracellular matrix (ECM) components, resulting in normal cardiac structural damage and cardiac fibrosis. We previously found that human endothelial progenitor cell (EPC)-derived exosomes, after hypoxia/reoxygenation (H/R) induction, could significantly increase the mesenchymal-endothelial transition (MEndoT) compared to normal culture EPC-derived exosomes. Exosomes have been shown to carry different nucleic acids, including microRNAs. However, the effects of microRNAs in EPC-derived exosomes on MEndoT and myocardial fibrosis remain unknown. METHODS: EPCs were isolated from human peripheral blood, and fibroblasts were isolated from rat hearts, then transfected with miR-133 inhibitor, si-YBX-1, and ov-YBX-1 into EPCs. After H/R induction for 48 h, isolation and characterization of exosomes derived from human EPCs were performed. Finally, fibroblasts were treated by exosome at 48 h. The expression of miR-133 was measured by qRT-PCR; YBX-1 expression was measured by qRT-PCR and western blot. Angiopoiesis was measured by tube formation assay. Endothelial markers and fibrosis markers were measured by western blot. RESULTS: H/R treatment promoted miR-133 expression in EPCs and EPC-derived exosomes. miR-133 could be incorporated into exosomes and transmitted to cardiac fibroblasts, increasing the angiogenesis and MEndoT of cardiac fibroblasts. miR-133 silencing in H/R-induced EPCs could inhibit miR-133 expression in EPCs and EPCs-derived exosomes. miR-133 silencing in H/R-induced EPCs could inhibit the angiogenesis and MEndoT of cardiac fibroblasts and reverse the effect of H/R treatment. Additionally, miR-133 was specially sorted into H/R-induced EPC-derived exosomes via YBX-1. YBX-1 silencing inhibited miR-133 transfer and reduced fibroblast angiogenesis and MEndoT. CONCLUSION: miR-133 was specially sorted into H/R-induced EPC-derived exosomes via YBX-1 to increase fibroblast angiogenesis and MEndoT.

20.
J Environ Manage ; 250: 109467, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470195

RESUMO

This study investigated the gasification of wood, weed, plastic, tire, carton and their mixtures using zeolite (A4 type) as a catalyst, with the purpose of investigating the potential interactions of the various feedstocks during gasification. The co-gasification of the mixed feedstock led to the occurrences of the cross-interactions, which substantially impacted the distribution of the products in gasification. During the co-gasification, the pyrolysis/gasification of the different feedstocks produced the reaction intermediates with varied structures that interacted with each other and with the char formed from the different feedstock. The interaction could promote the gasification of the tarry compounds into gaseous products, which could also promote the gasification of the char to lower the char yields. Further to this, the cross-polymerisation or cracking of the varied reaction intermediates also took place during the co-gasification, leading to the formation of more coke deposits on catalyst. The co-gasification of the mixed feedstocks significantly impacted the reaction network, impacting the formation of gases, tar, char and the coke on catalysts, originating from the cross-interaction among the reaction intermediates derived from the pyrolysis/gasification of the various feedstocks.


Assuntos
Plásticos , Madeira , Biomassa , Catálise , Gases
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