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1.
Adv Sci (Weinh) ; : e2309303, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582516

RESUMO

The development of highly active, reusable catalysts for aqueous-phase reactions is challenging. Herein, metallic nickel is encapsulated in a nitrogen-doped carbon-silica composite (SiO2@Ni@NC) as a catalyst for the selective hydrogenation of vanillin in aqueous media. The constructed catalyst achieved 99.8% vanillin conversion and 100% 4-hydroxymethyl-2-methoxyphenol selectivity at room temperature. Based on combined scanning transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman analyses, the satisfactory catalytic performance is attributed to the composite structure consisting of an active metal, carbon, and silica. The hydrophilic silica core promoted dispersion of the catalyst in aqueous media. Moreover, the external hydrophobic NC layer has multiple functions, including preventing oxidation or leaching of the internal metal, acting as a reducing agent to reduce the internal metal, regulating the active-site microenvironment by enriching the concentrations of H2 and organic reactants, and modifying the electronic structure of the active metal via metal-support interactions. Density functional theory calculations indicated that NC facilitates vanillin adsorption and hydrogen dissociation to promote aqueous-phase hydrogenation. This study provides an efficient strategy for constructing encapsulated Ni-based amphiphilic catalysts to upgrade biomass-derived compounds.

2.
Circulation ; 149(16): 1258-1267, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38406848

RESUMO

BACKGROUND: Postprocedural anticoagulation (PPA) is frequently administered after primary percutaneous coronary intervention in ST-segment-elevation myocardial infarction, although no conclusive data support this practice. METHODS: The RIGHT trial (Comparison of Anticoagulation Prolongation vs no Anticoagulation in STEMI Patients After Primary PCI) was an investigator-initiated, multicenter, randomized, double-blind, placebo-controlled, superiority trial conducted at 53 centers in China. Patients with ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention were randomly assigned by center to receive low-dose PPA or matching placebo for at least 48 hours. Before trial initiation, each center selected 1 of 3 PPA regimens (40 mg of enoxaparin once daily subcutaneously; 10 U·kg·h of unfractionated heparin intravenously, adjusted to maintain activated clotting time between 150 and 220 seconds; or 0.2 mg·kg·h of bivalirudin intravenously). The primary efficacy objective was to demonstrate superiority of PPA to reduce the primary efficacy end point of all-cause death, nonfatal myocardial infarction, nonfatal stroke, stent thrombosis (definite), or urgent revascularization (any vessel) within 30 days. The key secondary objective was to evaluate the effect of each specific anticoagulation regimen (enoxaparin, unfractionated heparin, or bivalirudin) on the primary efficacy end point. The primary safety end point was Bleeding Academic Research Consortium 3 to 5 bleeding at 30 days. RESULTS: Between January 10, 2019, and September 18, 2021, a total of 2989 patients were randomized. The primary efficacy end point occurred in 37 patients (2.5%) in both the PPA and placebo groups (hazard ratio, 1.00 [95% CI, 0.63 to 1.57]). The incidence of Bleeding Academic Research Consortium 3 to 5 bleeding did not differ between the PPA and placebo groups (8 [0.5%] vs 11 [0.7%] patients; hazard ratio, 0.74 [95% CI, 0.30 to 1.83]). CONCLUSIONS: Routine PPA after primary percutaneous coronary intervention was safe but did not reduce 30-day ischemic events. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03664180.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Anticoagulantes/efeitos adversos , Enoxaparina/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Heparina/efeitos adversos , Infarto do Miocárdio/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Fragmentos de Peptídeos/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Proteínas Recombinantes , Infarto do Miocárdio com Supradesnível do Segmento ST/tratamento farmacológico , Resultado do Tratamento
3.
Angew Chem Int Ed Engl ; 62(52): e202314414, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37946623

RESUMO

The integration of highly active single atoms (SAs) and atom clusters (ACs) into an electrocatalyst is critically important for high-efficiency two-electron oxygen reduction reaction (2e- ORR) to hydrogen peroxide (H2 O2 ). Here we report a tandem impregnation-pyrolysis-etching strategy to fabricate the oxygen-coordinated Fe SAs and ACs anchored on bacterial cellulose-derived carbon (BCC) (FeSAs/ACs-BCC). As the electrocatalyst, FeSAs/ACs-BCC exhibits superior electrocatalytic activity and selectivity toward 2e- ORR, affording an onset potential of 0.78 V (vs. RHE) and a high H2 O2 selectivity of 96.5 % in 0.1 M KOH. In a flow cell reactor, the FeSAs/ACs-BCC also achieves high-efficiency H2 O2 production with a yield rate of 12.51±0.18 mol gcat -1 h-1 and a faradaic efficiency of 89.4 %±1.3 % at 150 mA cm-2 . Additionally, the feasibility of coupling the produced H2 O2 and electro-Fenton process for the valorization of ethylene glycol was explored in detail. The theoretical calculations uncover that the oxygen-coordinated Fe SAs effectively regulate the electronic structure of Fe ACs which are the 2e- ORR active sites, resulting in the optimal binding strength of *OOH intermediate for high-efficiency H2 O2 production.

4.
Angew Chem Int Ed Engl ; 62(6): e202210958, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36263900

RESUMO

The development of efficient electrocatalysts to generate key *NH2 and *CO intermediates is crucial for ambient urea electrosynthesis with nitrate (NO3 - ) and carbon dioxide (CO2 ). Here we report a liquid-phase laser irradiation method to fabricate symbiotic graphitic carbon encapsulated amorphous iron and iron oxide nanoparticles on carbon nanotubes (Fe(a)@C-Fe3 O4 /CNTs). Fe(a)@C-Fe3 O4 /CNTs exhibits superior electrocatalytic activity toward urea synthesis using NO3 - and CO2 , affording a urea yield of 1341.3±112.6 µg h-1 mgcat -1 and a faradic efficiency of 16.5±6.1 % at ambient conditions. Both experimental and theoretical results indicate that the formed Fe(a)@C and Fe3 O4 on CNTs provide dual active sites for the adsorption and activation of NO3 - and CO2 , thus generating key *NH2 and *CO intermediates with lower energy barriers for urea formation. This work would be helpful for design and development of high-efficiency dual-site electrocatalysts for ambient urea synthesis.

5.
Adv Sci (Weinh) ; 9(35): e2204043, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36310149

RESUMO

Direct electrocatalytic oxidation of benzene has been regarded as a promising approach for achieving high-value phenol product, but remaining a huge challenge. Here an oxygen-coordinated nickel single-atom catalyst (Ni-O-C) is reported with bifunctional electrocatalytic activities toward the two-electron oxygen reduction reaction (2e- ORR) to H2 O2 and H2 O2 -assisted benzene oxidation to phenol. The Ni-(O-C2 )4 sites in Ni-O-C ar proven to be the catalytic active centers for bifunctional 2e- ORR and H2 O2 -assisted benzene oxidation processes. As a result, Ni-O-C can afford a benzene conversion as high as 96.4 ± 3.6% with a phenol selectivity of 100% and a Faradaic efficiency (FE) of 80.2 ± 3.2% with the help of H2 O2 in 0.1 m KOH electrolyte at 1.5 V (vs RHE). A proof of concept experiment with Ni-O-C concurrently as cathode and anode in a single electrochemical cell demonstrates a benzene conversion of 33.4 ± 2.2% with a phenol selectivity of 100% and a FE of 44.8 ± 3.0% at 10 mA cm-2 .

6.
BMC Cardiovasc Disord ; 22(1): 120, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35313827

RESUMO

BACKGROUND: Radial artery (RA) atherosclerosis in acute coronary syndrome (ACS) patients has not been systematically observed in vivo. The study aims to characterize plaque morphology and intimal hyperplasia of the RA in patients with ACS, using optical coherence tomography (OCT). METHODS: In this retrospective study involving 239 ACS patients underwent RA OCT without guidewire shadow, 3 groups were divided according to the following criteria: radial artery plaque (RAP) group included patients with fibrous, lipid or calcified plaque; patients without RAP were further classified into radial intimal hyperplasia (RIH) group (intima media thickness ratio [IMR] ≥ 1) or normal group (IMR < 1). The presence and characteristics of RAP and its related risk factors were identified. RESULTS: The RAP, RIH and normal groups included 76 (31.8%), 69 (28.9%) and 94 (39.3%) patients, respectively. Patients in RAP group were the oldest, compared with those in the RIH and normal groups (p < 0.001), and more frequently had triple vessel disease (p = 0.004). The percentage of plaque rupture (72.4% vs. 56.4%, p = 0.018) and calcification (42.1% vs. 27.6%, p = 0.026) at culprit lesion were significantly higher in patients with RAP than those without RAP. A total of 148 RAP were revealed by OCT, including fibrous (72, 48.6%), lipid (50, 33.8%) and calcified plaques (26, 17.6%). The microvessels were also frequently observed in the RAP group than that in RIH and normal groups (59.2% vs. 8.7% vs. 9.6%, p < 0.001). Multivariate logistic regression analysis showed that age, diabetes, and smoking history (all p < 0.05) were independent risk factors for RAP. CONCLUSIONS: In terms of insights gained from OCT, RA atherosclerosis is not uncommon in ACS patients by OCT, sharing several morphological characters with early coronary atherosclerosis. Aging, diabetes, and smoking are risk factors for RAP.


Assuntos
Síndrome Coronariana Aguda , Aterosclerose , Doença da Artéria Coronariana , Placa Aterosclerótica , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/etiologia , Síndrome Coronariana Aguda/patologia , Aterosclerose/diagnóstico por imagem , Aterosclerose/patologia , Espessura Intima-Media Carotídea , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Humanos , Hiperplasia/patologia , Lipídeos , Artéria Radial/diagnóstico por imagem , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos
7.
ACS Appl Mater Interfaces ; 13(40): 47684-47695, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34607432

RESUMO

Rational design of advanced adsorbed materials with hierarchically porous architecture, high surface area, and macroscopic shapeability is of great significance for boosting their potential in practical applications. Herein, a monolithic iron metal-organic gel/bacterial cellulose (denoted as Fe-MOG/BC) composite has been successfully fabricated based on an ultrafast, scalable, aqueous-based synthetic strategy at room temperature. As expected, the resulting Fe-MOG/BC aerogel possesses a three-dimensional (3D) hierarchically porous microstructure and abundant active sites, being ultralight, water-fast, and mechanically robust. Benefiting from these unique structural characteristics, the resulting Fe-MOG/BC composite exhibits superb saturated sorption capacity (495 mg g-1) toward arsenate, outperforming other reported nanoadsorbents. Further, the Fe-MOG/BC aerogel enables efficient decontamination of 5 ppm of As(V) to below the permitted threshold in drinking water (10 ppb) within 30 min, accompanied by excellent selectivity and reusability. Significantly, as an efficient filter unit, the Fe-MOG/BC aerogel (0.1 g) can continuously treat 3900 mL wastewater (spiked with 1 ppm As(V)) to the safe level. Such an excellent As(V) decontamination capability of Fe-MOG/BC together with the ease, low cost, and scalable production prefigures its huge prospects for practical wastewater remediation.

8.
Chem Commun (Camb) ; 56(49): 6696-6699, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32412027

RESUMO

ZIF-8 was employed as a template to synthesize HD-Ni/N-CMS containing highly dispersed Ni at the atomic level anchored on a N-doped carbon molecular sieve for vanillin hydrodeoxygenation. The ZIF-8 structure was inherited and Ni-N bonds were formed by the coordination of Ni with N-rich defects, therefore it exhibited a high turnover frequency (1047.1 h-1) and good stability.

9.
Transl Vis Sci Technol ; 8(6): 22, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31788351

RESUMO

PURPOSE: To investigate the association between changes in arterial blood gases and intraocular pressure (IOP) after acute, short-term exposure to simulated elevation of 4000 m above sea level. METHODS: Twenty-five healthy young lowlanders participated in this prospective study. IOP was measured in both eyes with an Accupen tonometer. Arterial blood gas parameters (partial oxygen pressure [PaO2], partial carbon dioxide pressure [PaCO2], pH, and bicarbonate ion [HCO3 -]) were checked using a blood gas analyzer. Measurements were taken at sea level (T1), at 15-minute (T2) and at 2-hour (T3) exposure times to simulated 4000 m above sea level in a hypobaric chamber, and upon return to sea level (T4). Associations between arterial blood gas parameters and IOP were evaluated using multivariate linear regression. RESULTS: PaO2 significantly decreased at T2 and T3, resolving at T4 (P < 0.001). pH significantly increased at T2 and returned to baseline at T3 (P = 0.004). Actual and standard bicarbonate ion both dropped with IOP at T3 and T4. IOP significantly decreased from 16.4 ± 3.4 mm Hg at T1 to 15.1 ± 2.1 mm Hg (P = 0.041) at T3 and remained lower (14.9 ± 2.4 mm Hg; P = 0.029) at T4. IOP was not correlated with pH. Multivariate linear regression showed that lower IOP was associated with lower standard bicarbonate ion (beta = -1.061; 95% confidence interval, -0.049 to -2.074; P = 0.04) when adjusted for actual bicarbonate and diastolic blood pressure. CONCLUSIONS: Hypobaric hypoxia triggers plasma bicarbonate ion reduction which, rather than pH, may decrease aqueous humor formation and subsequently cause IOP reduction. These findings may shed light on the mechanism of IOP regulation at high altitude. TRANSLATIONAL RELEVANCE: Hypoxia-triggered reduction in plasma bicarbonate ion may decrease aqueous humor production, leading to IOP reduction at high altitude. These findings may provide new insight into a potential mechanism of IOP regulation. Hypobaric hypoxia at high altitude is an environmental factor that can reduce IOP and, therefore, deserves further study.

10.
Nanoscale ; 11(25): 12161-12168, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31197303

RESUMO

Frequent oil spill accidents and ever-increasing oily wastewater have become serious global environmental problems. To enhance the oil-sorption capacity and simplify the oil-recovery process, the construction of various advanced oil sorbents and oil-collecting devices is of great technological importance. Herein, a three-dimensional (3D) porous carbon-based hybrid monolith has been successfully fabricated, in which cobalt based metal-organic framework (Co-MOF) nanosheets are firstly immobilized on a carbon foam (CF) skeleton (denoted as Co-MOFs/CF) via a facile vapor-phase hydrothermal (VPH) technique followed by carbonation treatment under a N2 atmosphere into Co@C/CF. The resulting Co@C/CF hybrid monolith exhibits an exceptional oil/water separation ability, including high sorption capacity (from 85 to 200 times its own weight toward various solvents and oils), easy collection and remarkable recyclability, as reflected by no obvious reduction in uptake capacity even after 20 cycles of repeated operation. More significantly, the oil-collecting device based on the proposed carbon-based hybrid monolith can rapidly, efficiently, and continuously collect oil from water surfaces, making it a promising candidate for oil-spill remediation.

11.
J Colloid Interface Sci ; 532: 37-46, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30077065

RESUMO

We investigate the possibility of utilizing benzyl alcohol oxidation reaction to replace sluggish oxygen evolution reaction (OER) for the charging process in a rechargeable zinc-air battery, catalyzed by NiCo alloy nanoparticles supported on activated carbon (NiCo/AC) with the multifunctional electrocatalytic activities of the oxygen reduction, oxygen evolution and benzyl alcohol oxidation reactions. As an electrocatalyst for the oxygen reduction reaction (OER), NiCo/AC exhibits superior catalytic activity with an onset potential of 0.85 V (vs. RHE), a half-wave potential of 0.74 V (vs. RHE) and a large limiting current density of 4.65 mA cm-2 at 0.2 V (vs. RHE). Moreover, NiCo/AC also demonstrates the electrocatalytic oxidation activities toward water and benzyl alcohol, moreover, the benzyl alcohol oxidation reaction is more thermodynamically and kinetically favourable with 254 mV smaller overpotential than water oxidation at 10 mA cm-2. Owing to these advantages, NiCo/AC as air cathode material is assembled into a home-made rechargeable zinc-air battery, resulting an almost 200 mV lower charging voltage at the current density of 50 mA cm-2 in the presence of 0.1 M benzyl alcohol compared to the battery without benzyl alcohol, consequently obtaining 10.5% energy saving at the charging current density of 50 mA cm-2 with high durability.

12.
ACS Omega ; 3(6): 6955-6961, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31458861

RESUMO

The remediation of soil contaminated by 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) has been a challenge. In this paper, the degradation performances of the ball milling-induced plate-like sub-microstructured zero valent iron (SMZVI) to DDT in a real soil environment is studied. It has been found that such SMZVI exhibits much higher degradation performances to DDT in soil than commercial ZVI powders under acidic conditions. More than 95% DDT could be degraded within 80 min in the 5 ppm DDT-contaminated soil with addition of 50 mg g-1 SMZVI, which is much better than the previously reported results. The time-dependent DDT removal amount can be well described by the pseudo first-order kinetic model. Further experiments have revealed that the ZVI dosages, surfactant's and acidic additions, and the weight ratio of soil-to-water in the slurries are important to DDT degradation, and the degradation products were mainly DDD (a product with less chlorine). An acid-assisted ZVI-induced reductive dechlorination process is proposed, which can well explain the DDT degradation behaviors in soil and the influence from the other factors. This work not only deepens the understanding of DDT degradation in soils based on ZVI but also demonstrates that the SMZVI could be a promising material for DDT degradation in real environments.

13.
Med Sci Monit ; 23: 5302-5310, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29112682

RESUMO

BACKGROUND This study aimed to observe the effect of lentivirus-mediated cyclooxygenase-2 and aggrecanase-1 silencing and insulin-like growth factor-1 overexpression in human bone marrow mesenchymal stem cells after injection into model osteoarthritic knees. MATERIAL AND METHODS Using genetic recombination technique, the genes of cyclooxygenase-2, aggrecanase-1, and insulin-like growth factor-1 were recombined into the lentiviral vectors, and we transfected the human bone marrow stem cells in vitro. The BMSC transfected with lentivirus without genes served as a blank-virus group, and saline was used for another control group. One week later, the cytokines PGE2, aggrecanase-1, hIGF-1, and IL-1 were detected and compared between groups. RESULTS Compared with blank-virus group, the expression of COX-2 (85.81±5.12 ng/L) and aggrecanase1 (6.256±1.66) were decreased in the virus group (p<0.05), while the expression of hIGF-1 (17.46±1.86) was increased (p<0.05). The concentrations of PGE2 (85.81±5.12 ng/L), aggrecanase1 (51.34±5.463 ng/L), and IL-1 (82.31±4.321 ng/L) decreased (p<0.05) within the knee, but the concentration of hIGF-1 (44.33±0.7194 ng/L) increased (p<0.05). Compared with the other groups, the results of histological and immunohistochemical examinations demonstrated that the abrasion of articular cartilage was significantly improved and repaired. CONCLUSIONS Lentivirus-mediated RNAi can inhibit the expression of COX-2 mRNA and aggrecanase-1mRNA, and enhance the hIGF-1 mRNA expression, thereby influencing the concentration of cytokines in the early osteoarthritic model knee joints.


Assuntos
Proteína ADAMTS4/genética , Ciclo-Oxigenase 2/genética , Fator de Crescimento Insulin-Like I/biossíntese , Transplante de Células-Tronco Mesenquimais/métodos , Osteoartrite/terapia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Cartilagem Articular/patologia , Modelos Animais de Doenças , Inativação Gênica , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Joelho/fisiologia , Lentivirus/genética , Macaca fascicularis , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , Transfecção
14.
J Colloid Interface Sci ; 478: 421-9, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27362398

RESUMO

A facile freeze-drying method was presented to fabricate three dimensional (3D) honeycomb-like structured nanoscale zero-valent iron/chitosan composite foams (ICCFs) for effective removal of inorganic arsenic in water. It was found that freezing temperature has important influence on the formation of 3D network structure of ICCFs. The ICCFs obtained at freeze temperature of -80°C exhibits oriented porous structure with good mechanical property than that at -20°C, thus improved excellent removal capability of As(III) and As(V) up to 114.9mgg(-1) and 86.87mgg(-1), respectively. Further, the adsorption kinetics of ICCFs on As(III) and As(V) can be described by pseudo-second order model and their adsorption isotherms follow Langmuir adsorption model. The superior removal performance of ICCFs on As(III) and As(V) can be ascribed to its oriented porous structure with abundant adsorption active sites resulted from nZVI and O, N-containing functional groups in ICCFs. Importantly, it was found that the O, N-containing functional groups of chitosan in ICCFs can adequately bind with the dissolved Fe(3+) ions from oxidation of nZVI to form Fe(3+)-Chitosan complex during removal of As(III) and As(V), thus effectively avoiding the dissolved Fe(3+) ions into solution to produce secondary pollution. A possible adsorption-coupled reduction mechanism of ICCFs on As(III) and As(V) was also proposed based on the experimental results. We believe that this work would be helpful to develop low-cost and abundant chitosan-based materials as high performance adsorbents for environmental remediation applications.

15.
J Hazard Mater ; 314: 188-196, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27131459

RESUMO

Nanotechnology is advancing rapidly and substantial amounts of nanomaterials are released into the environment. Plants are an essential base component of the ecological environment and play a critical role in the fate and transport of nanomaterials in the environment through plant uptake and bioaccumulation. In this study, plant uptake of gold nanoparticles (GNPs) functionalized with three types of short ligands [cysteamine (CA), cysteine (CYS) and thioglycolic acid (TGA)] and of nearly identical hydrodynamic size (8-12nm) was investigated in the major crops rice (Oryza sativa L.) and tomato (Solanum lycopersicum). Uptake and translocation of GNPs not only depended on particle surface charge, but were also related to the species of ligand on the GNPs. The negatively charged GNPs capped with the CYS ligand (GNP-CYS) were more efficiently absorbed in roots and transferred to shoots (including stems and leaves) than that of GNPs capped with CA and TGA. The absorption process of GNPs involved a combination of both clathrin-dependent and -independent mechanisms. The endocytosis of GNPs was strongly inhibited by wortmannin, suggesting that clathrin-independent endocytosis was an important pathway of nanoparticle internalization in plants. Competition experiments with a free ligand (CYS) showed that the CYS ligand probably facilitated the endocytosis process of GNPs and increased the internalization of GNP-CYS in plants. The results will aid understanding of the mechanisms of nanoparticle uptake and translocation in plants.


Assuntos
Ouro/farmacocinética , Nanopartículas Metálicas , Oryza/metabolismo , Solanum lycopersicum/metabolismo , Cisteamina/metabolismo , Cisteína/metabolismo , Ligantes , Tioglicolatos/metabolismo
16.
Artigo em Chinês | MEDLINE | ID: mdl-26540986

RESUMO

OBJECTIVE: To explore the ettect and mechanisms of bone marrow mesenchymal stem cells (BMSCs) on healing quality of acetic acid-induced gastric ulcer. METHODS: Forty-eight clean grade male Wistar rats were used to establish the model of gastric ulcer with acetic acid and were randomly divided into 3 groups after 3 days of modeling, 16 rats each group. After the abdominal cavity was open and stomach was pulled out, no treatment was given in group A, 150 µL phosphate buffered saline (PBS) and 150 µL BMSCs at passage 4+PBS (1 x 10(8) cells/100 µL) were injected into the gastric wall surrounding the ulcer at 5 different points in groups B and C respectively. After 10 days, the ulcer area was measured, the mucosal thickness and the number of dilated glands were tested in the regenerative mucosa by histological method. And the expression of vascular endothelial growth factor (VEGF) was detected at ulcerative margin by immunohistochemical method. RESULTS: The ulcer area in group C was significantly smaller than that of groups A and B (P < 0.01), but no significant difference was found between groups A and B (P > 0.05). HE staining showed that group C had thicker regenerative gastric mucosa, less dilated glands, and more regular mucosal structure than groups A and B, showing significant differences in regenerative gastric mucosa thickness and dilated glands number (P < 0.01), but no significant difference between groups A and B (P > 0.05). Immunohistochemical staining showed that the positive expression of VEGF in the ulcer margin mucosa of group C was significantly higher than that of groups A and B. The integral absorbance (IA) value of VEGF expression in group C was significantly higher than that in groups A and B (P < 0.01), but no significant difference between groups A and B (P > 0.05). CONCLUSION: BMSCs can accelerate ulcer healing by the secretion of VEGF, and improve the quality of ulcer healing.


Assuntos
Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Mucosa Gástrica/fisiologia , Úlcera Gástrica/terapia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Células da Medula Óssea , Fator 2 de Crescimento de Fibroblastos/fisiologia , Mucosa Gástrica/irrigação sanguínea , Células-Tronco Hematopoéticas , Masculino , Ratos , Ratos Wistar , Úlcera Gástrica/fisiopatologia , Cicatrização
17.
ACS Appl Mater Interfaces ; 7(44): 24902-8, 2015 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-26497199

RESUMO

Anatase hierarchical TiO2 with innovative designs (hollow microspheres with exposed high-energy {001} crystal facets, hollow microspheres without {001} crystal facets, and solid microspheres without {001} crystal facets) were synthesized via a one-pot hydrothermal method and characterized. Based on these materials, gas sensors were fabricated and used for gas-sensing tests. It was found that the sensor based on hierarchical TiO2 hollow microspheres with exposed high-energy {001} crystal facets exhibited enhanced acetone sensing properties compared to the sensors based on the other two materials due to the exposing of high-energy {001} crystal facets and special hierarchical hollow structure. First-principle calculations were performed to illustrate the sensing mechanism, which suggested that the adsorption process of acetone molecule on TiO2 surface was spontaneous, and the adsorption on high-energy {001} crystal facets would be more stable than that on the normally exposed {101} crystal facets. Further characterization indicated that the {001} surface was highly reactive for the adsorption of active oxygen species, which was also responsible for the enhanced sensing performance. The present studies revealed the crystal-facets-dependent gas-sensing properties of TiO2 and provided a new insight into improving the gas sensing performance by designing hierarchical hollow structure with special-crystal-facets exposure.

18.
J Hazard Mater ; 289: 210-218, 2015 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-25725344

RESUMO

Natural diatomite was modified through facile acid treatment and ultrasonication, which increased its electronegativity, and the pore volume and surface area achieved to 0.211 cm(3) g(-1) and 76.9 m(2) g(-1), respectively. Modified diatomite was investigated to immobilize the potential toxic elements (PTEs) of Pb, Cu and Cd in simulated contaminated soil comparing to natural diatomite. When incubated with contaminated soils at rates of 2.5% and 5.0% by weight for 90 days, modified diatomite was more effective in immobilizing Pb, Cu and Cd than natural diatomite. After treated with 5.0% modified diatomite for 90 days, the contaminated soils showed 69.7%, 49.7% and 23.7% reductions in Pb, Cu and Cd concentrations after 0.01 M CaCl2 extraction, respectively. The concentrations of Pb, Cu and Cd were reduced by 66.7%, 47.2% and 33.1% in the leaching procedure, respectively. The surface complexation played an important role in the immobilization of PTEs in soils. The decreased extractable metal content of soil was accompanied by improved microbial activity which significantly increased (P<0.05) in 5.0% modified diatomite-amended soils. These results suggested that modified diatomite with micro/nanostructured characteristics increased the immobilization of PTEs in contaminated soil and had great potential as green and low-cost amendments.


Assuntos
Cádmio/isolamento & purificação , Cobre/isolamento & purificação , Terra de Diatomáceas/química , Chumbo/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Cloreto de Cálcio/análise , Recuperação e Remediação Ambiental , Concentração de Íons de Hidrogênio , Solo , Microbiologia do Solo , Difração de Raios X
19.
Zhonghua Zhong Liu Za Zhi ; 36(2): 123-7, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24796461

RESUMO

OBJECTIVE: To investigate the clinical value of serum anti-Ku86 in early detection of hepatocellular carcinoma (HCC). METHODS: Expression levels of Ku86 protein in HCC and adjacent normal liver tissues were detected by Western blotting. Serum anti-Ku86 level in 83 patients with early HCC and 124 patients with liver cirrhosis were detected by enzyme-linked immunosorbent assay (ELISA). Chemiluminescence was used to measure the serum level of α-fetoprotein (AFP). RESULTS: Expression of Ku86 protein in HCC was increased when compared with the adjacent normal liver tissues (0.21 ± 0.05 vs. 0.08 ± 0.02, P < 0.01). Serum anti-Ku86 level was significantly elevated in HCC patients compared with that in liver cirrhosis patients (0.47 ± 0.22 vs. 0.22 ± 0.06 Abs at 450 nm, P < 0.01), but there was no significant difference between HBV infection and HCV infection in HCC patients (0.51 ± 0.19 vs. 0.47 ± 0.24, P = 0.267). Of note, serum anti-Ku86 level was significantly decreased after surgical resection of the tumors in the 30 HCC cases tested (P < 0.01). The results of ROC analysis indicated a better performance of anti-Ku86 (0.857) than AFP (0.739) for early detection of HCC. In 83 HCC patients, the positive rate of anti-Ku86 was 61.4% (51/83), significantly higher than that of the AFP positive rate (27.7%, 23/83). The anti-Ku86 level was positive in 37 of 60 HCC cases with negative AFP. Combination assay of AFP and anti-Ku86 could detect 60 of 83 HCC cases (72.3%, 60/83). There was no significant correlation of anti-Ku86 and AFP (r = 0.156, P = 0.161). CONCLUSIONS: Serum anti-Ku86 level is significantly elevated and is not related to HBV and HCV infection in HCC patients. Serum anti-Ku86 antibody may be a potential biomarker for early detection of HCC, and can be used in combination with AFP in clinics.


Assuntos
Antígenos Nucleares/imunologia , Autoanticorpos/sangue , Carcinoma Hepatocelular/diagnóstico , Proteínas de Ligação a DNA/imunologia , Neoplasias Hepáticas/diagnóstico , Adulto , Idoso , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/virologia , Detecção Precoce de Câncer , Feminino , Hepatite B/sangue , Hepatite C/sangue , Humanos , Autoantígeno Ku , Cirrose Hepática/sangue , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Curva ROC , alfa-Fetoproteínas/metabolismo
20.
Life Sci ; 93(25-26): 1033-8, 2013 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-24436993

RESUMO

AIMS: To evaluate the effects of hyperbaric oxygen (HBO) therapy on MMP-2 and MMP-9 expression and spinal cord edema after acute spinal cord injury (SCI). MAIN METHODS: Ninety-six healthy adult Sprague − Dawley rats were randomly divided into 4 groups: sham, sham + HBO, SCI, and SCI + HBO. Each group was subdivided into 4 subgroups of 6 rats each: 24 h, 48 h, 72 h, and 5 d post-injury. The expression levels of matrix metalloproteinase-2 (MMP-2), MMP-9, interleukin (IL-6), and vascular endothelial growth factor (VEGF) were measured using ELISA. The water content of the spinal cord was also measured by Elliot equation. KEY FINDING: MMP-2 and MMP-9 levels and spinal cord water content increased significantly in the SCI group compared to those in the sham and sham + HBO groups at different time points after SCI (P < 0.01). The MMP-2 level was significantly different between the SCI and SCI + HBO groups at 72 h after SCI (P < 0.05), while the MMP-9 level was significantly different at 48 h, 72 h, and 5 d (P < 0.05). The water content of the spinal cord was significantly higher in the SCI group at 5 d after SCI (P < 0. 01). MMP-2 (P < 0.05) and MMP-9 (P < 0.01) levels were positively correlated with spinal cord water content. SIGNIFICANCE: HBO reduced SCI-induced spinal cord edema, stabilized the blood-spinal cord barrier, and promoted recovery of neuronal function by down regulating the expression of IL-6, MMP-2, and MMP-9 and up regulating the expression of VEGF.


Assuntos
Edema/terapia , Oxigenoterapia Hiperbárica , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/terapia , Animais , Barreira Hematoencefálica , Edema/metabolismo , Interleucina-6/sangue , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/sangue
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