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1.
ACS Appl Bio Mater ; 7(2): 1169-1178, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38253011

RESUMO

Manganese dioxide (MnO2) is considered as a promising drug carrier material suitable for the tumor microenvironment while lacking conducive structures for drug loading. Herein, we construct a MnO2 nanoplatform with a hollow rhombic dodecahedral morphology for drug delivery. In this work, we obtained zeolitic imidazolate framework nanoparticles (ZIF-90 NPs) via a coordination reaction. Furthermore, the drug-loading nanoparticles (ZIF-90/DOX NPs) were obtained by Schiff's base reaction and then selected as a sacrificial template to obtain the hollow nanoplatforms (ZIF-90@MnO2 NPs). Moreover, the photothermal effect and multiresponsive drug release behaviors were revealed by loading the photothermal agent IR-820 and the anticancer drug doxorubicin hydrochloride (DOX). Our study demonstrates that the ZIF-90@MnO2 NPs loaded with photosensitizers exhibited excellent photothermal conversion performance. Benefiting from the hollow structure and redox activity, remarkable drug loading and release performances of ZIF-90@MnO2 NPs were achieved. It is shown that ZIF-90@MnO2 NPs achieved a satisfactory drug-loading efficiency (up to ca. 69.7%) for DOX. More promisingly, the ZIF-90@MnO2 NPs exhibited significant glutathione (GSH)/pH-responsive drug release and degradation performances. Overall, this work highlights the potential of controlled drug release of nanocarriers and offers unique insights into the design of nanocarriers with hollow structures.


Assuntos
Compostos de Manganês , Estruturas Metalorgânicas , Nanopartículas , Óxidos , Sistemas de Liberação de Medicamentos
2.
Dalton Trans ; 53(4): 1568-1574, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38164649

RESUMO

The use of an appropriate preparation route is the key to immobilize active molecules into a host matrix with high loadings and stability. Herein, we demonstrate a simple and general strategy to immobilize ferrocene and its derivatives into ZIF-8 with high loadings of up to 4.3% Fe content. The unique host pore structure allows for the stabilization of guest molecules and effectively prevents their leaching. As a result, the obtained electrocatalysts exhibit competitive oxygen evolution reaction (OER) catalytic performance. Optimized Fc-CHO/ZIF-8 requires only a low overpotential of 238 mV to achieve 10 mA cm-2, along with a relatively small Tafel slope of 44.4 mV dec-1. This performance is superior to that of commercial IrO2, suggesting its potential application in electrochemical energy conversion.

3.
Nat Commun ; 14(1): 259, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650152

RESUMO

The performance of all-solid-state lithium metal batteries (SSLMBs) is affected by the presence of electrochemically inactive (i.e., electronically and/or ionically disconnected) lithium metal and solid electrolyte interphase (SEI), which are jointly termed inactive lithium. However, the differentiation and quantification of inactive lithium during cycling are challenging, and their lack limits the fundamental understanding of SSLMBs failure mechanisms. To shed some light on these crucial aspects, here, we propose operando nuclear magnetic resonance (NMR) spectroscopy measurements for real-time quantification and evolution-tracking of inactive lithium formed in SSLMBs. In particular, we examine four different sulfide-based solid electrolytes, namely, Li10GeP2S12, Li9.54Si1.74P1.44S11.7Cl0.3, Li6PS5Cl and Li7P3S11. We found that the chemistry of the solid electrolyte influences the activity of lithium. Furthermore, we demonstrate that electronically disconnected lithium metal is mainly found in the interior of solid electrolytes, and ionically disconnected lithium metal is found at the negative electrode surface. Moreover, by monitoring the Li NMR signal during cell calendar ageing, we prove the faster corrosion rate of mossy/dendritic lithium than flat/homogeneous lithium in SSLMBs.

4.
ACS Appl Mater Interfaces ; 14(45): 50858-50869, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36331393

RESUMO

A vanadium flow battery (VFB) is one of the most promising electrochemical energy storage technologies. However, membranes for VFBs still suffer from high cost or low conductivity and poor stability. Here, we report new quaternized anthrone-containing poly(aryl ether ketone) (QAnPEK) membranes for VFBs. QAnPEK membranes with moderate ion exchange capacity (1.26 mmol g-1) were swelling-induced in H3PO4 (50 wt %) to form wider ion transport pathways that significantly enhanced membrane conductivity (e.g., 0.49 Ω cm2 for the QAnPEK-virgin membrane and 0.12 Ω cm2 for the swelling-induced QAnPEK-90 membrane). The bulky rigid anthrone-containing backbone provided high swelling resistance and enabled QAnPEK membranes to have high ion selectivity. As a result, QAnPEK membranes displayed low area resistance, high ion selectivity, and robust mechanical strength. The QAnPEK-90 membrane yielded excellent energy efficiencies (92.4% at 80 mA cm-2, 85.1% at 200 mA cm-2, and 80.3% at 280 mA cm-2). Moreover, QAnPEK membranes exhibited outstanding in situ and ex situ stability, for example, the VFB with the QAnPEK-40 membrane demonstrated highly stable battery performance for 3000 cycles at 160 mA cm-2. QAnPEK membranes are attractive candidates for VFB application.

5.
EClinicalMedicine ; 53: 101666, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36177443

RESUMO

Background: Glibenclamide is a promising agent for treating brain oedema, but whether it improves clinical outcomes in patients with intracerebral haemorrhage (ICH) remains unclear. In this study, we aimed to explore the efficacy and safety of glibenclamide treatment in patients with acute ICH. Methods: The Glibenclamide Advantage in Treating Oedema after Intracerebral Haemorrhage (GATE-ICH) study was a randomised controlled phase 2 clinical trial conducted in 26 hospitals in the northwest of China, recruiting patients with acute ganglia ICH no more than 72 h after onset from Dec 12, 2018 to Sept 23, 2020. During the first 7 days after enrolment, patients randomly assigned to the glibenclamide group were given glibenclamide orally (1.25 mg, 3/day) and standard care, while patients randomly assigned to the control group were given standard care alone. The computer-generated randomisation sequence was prepared by a statistician not involved in the rest of the study. Randomisation was computer-generated with a block size of four. The allocation results were unblinded to participants and investigators. The primary outcome was the percentage of patients with poor outcome (defined as modified Rankin Scale [mRS] score of ≥3) at day 90. The trial was registered at ClinicalTrials.gov (NCT03741530). Findings: 220 participants were randomised and 200 participants (mean [standard deviation] age, 56 [11] years; sex, 128 [64.0%] male and 72 [36.0%] female) were included in the final analysis, with 101 participants randomly assigned to the control group and 99 to the glibenclamide group. The incidence of poor outcome at day 90 was 20/99 (20.2%) in glibenclamide group and 30/101 (29.7%) in control group (absolute difference, 9.5%; 95% confidence interval [CI], -3.2%-21.8%; P = 0.121) with adjusted odds ratios of 0.54 (95% CI, 0.24-1.20; P = 0.129). No significant difference was found in the overall rates of adverse events or serious adverse events between groups. However, the incidence of asymptomatic hypoglycaemia was significantly higher in glibenclamide group than control group (15/99 [15.2%] vs 0/101 [0.0%]; absolute difference, 15.2%; 95% CI, 7.5%-24.1%; P < 0.001). Interpretation: Our study provides no evidence that glibenclamide (1.25 mg, 3/day) significantly reduces the proportion of poor outcome at day 90 after ICH. In addition, glibenclamide could result in higher incidence of hypoglycaemia. Larger trials of glibenclamide with optimised medication regimen are warranted. Funding: Shaanxi Province Key Research and Development Project (2017DCXL-SF-02-02) and Shaanxi Province Special Support Program for Leading Talents in Scientific and Technological Innovation (tzjhjw).

6.
Polymers (Basel) ; 14(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35458299

RESUMO

Membranes with high conductivity, high selectivity, and high stability are urgently needed for high-power-density vanadium flow batteries (VFBs). Enhancing membrane conductivity presents many challenges, often resulting in sacrificing membrane selectivity and mechanical strength. To overcome this, new robust adamantane-based membranes with enhanced conductivity are constructed for VFB. Low-content basic piperazine (IEC = 0.78 mmol g-1) and hydrophilic hydroxyl groups are introduced into highly rigid, hydrophobic adamantane containing poly(aryl ether ketone) backbone (PAPEK) and then selectively swelled to induce microphase separation and form ion transport pathways. The highly rigid and hydrophobic PAPEK exhibits high swelling resistance and provides the membranes with slight swelling, high selectivity, and high mechanical strength. The selective swelling temperature has a significant influence on the areal resistance of the resulting membrane, e.g., the PAPEK-130 membrane, when selectively swelled at 130 °C, has low areal resistance (0.22 Ω∙cm2), which is approximately two-fifths that of the PAEKK-60 membrane (treated at 60 °C, 0.57 Ω∙cm2). Consequently, the resulting PAPEK membranes exhibit low swelling, high selectivity, and low areal resistance, with the VFB constructed with a PAPEK-90 membrane exhibiting excellent energy efficiency (91.7%, at 80 mA∙cm-2, and 80.0% at 240 mA∙cm-2) and stable cycling performance for 2000 cycles.

7.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(5): 551-554, 2021 Sep 30.
Artigo em Chinês | MEDLINE | ID: mdl-34628771

RESUMO

OBJECTIVE: To establish an amino acid assay for the determination of ß-lactoglobulin in Anti-HPV biological protein dressing. METHODS: Under acidic conditions, ß-lactoglobulin is hydrolyzed into free amino acids, separated by cation exchange chromatography, and derivatived after ninhydrin column. The chromatogram at 570 nm is collected. The content of ß-lactoglobulin in the sample is indirectly determined by measuring the lysine content obtained by hydrolysis. RESULTS: ß-lactoglobulin has a good linear relationship in the concentration range of 77.28~309.12 µg/mL (y=5.060x+4.278, r=0.999 7); The recovery rate (n=9) is 100.06%. CONCLUSIONS: The method is simple, specific, accurate and reproducible, which is suitable for the quantitative analysis of ß-lactoglobulin in anti-HPV biological protein dressing.


Assuntos
Aminoácidos , Lactoglobulinas , Bandagens
8.
Ann Clin Transl Neurol ; 8(10): 2059-2069, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34587373

RESUMO

OBJECTIVE: To explore the effect of individualized blood pressure (BP)-lowering treatment on the outcomes of elderly patients with severe intracerebral hemorrhage (ICH). METHODS: We performed an exploratory analysis of Controlling Hypertension After Severe Cerebrovascular Event (CHASE) trial, which was a multicenter, randomized, controlled clinical trial. Patients with severe ischemic or hemorrhagic stroke (defined as GCS ≤ 12 or NIHSS ≥ 11) were randomized into individualized versus standard BP-lowering treatment in CHASE trial. In this exploratory analysis, patients with severe ICH were included. The primary outcome was the percentage of patients with 90-day functional independence defined as modified Rankin Scale (mRS) ≤2. RESULTS: We included 242 patients with severe ICH in the present analysis, consisting of 142 patients aged <65 years and 100 patients aged ≥65 years. There were significant differences between patients aged ≥65 years and <65 years in the proportion of functional independence (47.9% vs. 15.0%, P < 0.001) and good outcome (73.9% vs. 50.0%, P < 0.001) at day 90. In patients aged ≥65 years, the adjusted individualized BP-lowering treatment had an unequivocal effect on the functional independence at day 90 (21.6% vs. 8.2%, odds ratio [OR]: 4.309, 95% confidence interval [CI]: 1.040-17.859, P = 0.044) and improved the neurological deficits at discharge (∆ NIHSS ≥ 4: 64.7% vs. 34.7%, OR: 4.300, 95% CI: 1.599-11.563, P = 0.004). INTERPRETATION: Compared with the younger counterparts, the elderly patients (≥65 years) with acute severe ICH might benefit more from individualized BP-lowering treatment.


Assuntos
Anti-Hipertensivos/farmacologia , Hemorragia Cerebral/tratamento farmacológico , Hipertensão/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/administração & dosagem , Gerenciamento Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente
9.
Front Neurol ; 12: 656520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33986719

RESUMO

Introduction: Brain edema after acute intracerebral hemorrhage (ICH) plays a critical role in the secondary injury of ICH and may heighten the potential for a poor outcome. This trial aims to explore the efficacy of small doses of oral glibenclamide in perihematomal edema (PHE) and the prognosis of patients with ICH. Methods and Analysis: The GATE-ICH trial is a multicenter randomized, controlled, assessor-blinded trial. A total of 220 adult patients with acute primary ICH in 28 study centers in China will be randomized to the glibenclamide group (glibenclamide plus guideline-recommended ICH management) or the control group (guideline-recommended ICH management). Multivariate logistic regression will be used to analyze the relationship between the treatments and primary outcome. Study Outcomes: The primary efficacy outcome is the proportion of poor functional outcomes (modified Rankin Scale ≥3) at 90 days after enrollment. The secondary efficacy outcomes include changes in the volume of ICH and PHE between the baseline and follow-up computed tomography scans as well as the clinical scores between the baseline and follow-up assessments. Discussion: The GATE-ICH trial will assess the effects of small doses of oral glibenclamide in reducing the PHE after ICH and improving the 90-day prognosis of patients. Clinical Trial Registration: www.clinicaltrials.gov., NCT03741530. Registered on November 8, 2018. Trial Status: Protocol version: May 6, 2019, Version 5. Recruitment and follow-up of patients is currently ongoing. This trial will be end in the second quarter of 2021.

10.
Int J Stroke ; 16(4): 456-465, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32525464

RESUMO

BACKGROUND: The optimal blood pressure lowering target in the acute phase of severe stroke is uncertain. Our aim was to compare the efficacy and safety of individualized blood pressure lowering with standard blood pressure lowering in severe stroke. METHODS: Five-hundred consecutive patients with acute severe stroke and elevated BP were recruited from 26 Chinese hospitals. Eligible patients were randomized into an individualized blood pressure lowering group (with 10-15% reduction in systolic blood pressure from admission level or standard blood pressure lowering group (with a target SBP of <200 mm Hg in acute ischemic stroke and <180 mm Hg in intracerebral hemorrhage). The primary outcome was the proportion of patients with a poor functional outcome at day 90 of enrolment. RESULTS: Of 483 participants included in the analysis, 242 received individualized blood pressure lowering treatment and 241 received standard treatment. The primary outcome event was observed in 71.1% of the participants in the individualized treatment group and in 73.4% of the standard treatment group (odds ratio with individualized treatment for primary outcome, 0.75; 95% confidence interval, 0.47 to 1.19; p = 0.222). The rates of serious adverse events in the two groups were similar (27.7% vs. 28.2%). CONCLUSIONS: In patients with acute severe stoke, individualized blood pressure lowering treatment did not significantly reduce the rate of three-month death or dependence. TRIAL REGISTRATION: Clinicaltrials.gov, NCT02982655. Registered in 5 December 2016, https://clinicaltrials.gov/ct2/show/NCT02982655.


Assuntos
Isquemia Encefálica , Hipertensão , Acidente Vascular Cerebral , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Isquemia Encefálica/tratamento farmacológico , Humanos , Hipertensão/tratamento farmacológico , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do Tratamento
11.
RSC Adv ; 11(24): 14426-14433, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35423959

RESUMO

Dimethyl ether (DME) can be directly synthesized from carbon dioxide and hydrogen by mixing methanol synthesis catalysts and methanol dehydration catalysts. The activity and selectivity of the catalyst can be greatly affected by the promoter; herein, we presented a series of CuO-ZnO-Ga2O3/HZSM-5 hybrid catalysts, which were prepared by the coprecipitation method. The effect of the Ga2O3 content on the structure and performance of the Ga-promoted Cu-ZnO/HZSM-5 based catalysts was thoroughly investigated. The results showed that the addition of Ga2O3 significantly increased specific surface areas and Cu areas, decreased the size of Cu particles, maintained the proportion of Cu+/Cu0 on the surface of the catalyst, and strengthened the metal-support interaction, resulting in high catalytic performance.

12.
J Clin Hypertens (Greenwich) ; 23(1): 96-102, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33226186

RESUMO

The influence of blood pressure variability (BPV) on outcomes in patients with severe stroke is still largely unsettled. Using the data of CHASE trial, the authors calculated the BPV during the acute phase and subacute phase of severe stroke, respectively. The primary outcome was to investigate the relationship between BPV and 90-day modified Rankin scale (mRS) ≥ 3. The BPV was assessed by eight measurements including standard deviation (SD), mean, maximum, minimum, coefficient of variation (CV), successive variation (SV), functional successive variation (FSV), and average real variability (ARV). Then, the SD of SBP was divided into quintiles and compared the quintile using logistic regression in three models. The acute phase included 442 patients, and the subacute phase included 390 patients. After adjustment, six measurements of BPV during the subacute phase rather than acute phase were strongly correlated with outcomes including minimum (odds ratio [OR]: 0.83, 95% confidence interval [CI]: 0.69-0.99, p = .037), SD (OR: 1.10, 95% CI: 1.03-1.17, p = .007), CV (OR: 1.12, 95% CI: 1.03-1.23, p = .012), ARV (OR: 1.13, 95% CI: 1.05-1.20, p < .001), SV (OR: 1.09, 95% CI: 1.04-1.15, p = .001), and FSV (OR: 1.12, 95% CI: 1.05-1.19, p = .001). In the logistic regression, the highest fifth of SD of SBP predicted poor outcome in all three models. In conclusion, the increased BPV was strongly correlated with poor outcomes in the subacute phase of severe stroke, and the magnitude of association was progressively increased when the SD of BP was above 12.


Assuntos
Hipertensão , Acidente Vascular Cerebral , Pressão Sanguínea , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Modelos Logísticos , Razão de Chances , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia
13.
Ying Yong Sheng Tai Xue Bao ; 31(2): 433-440, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32476335

RESUMO

The spectrometer-based nitrogen (N) nutrition monitoring and diagnosis models for double-cropping rice in Jiangxi is important for recommending precise N topdressing rate, achieving high yield, improving grain quality and increasing economic efficiency. Field experiments were conducted in Jiangxi in 2016 and 2017, involving different early rice and late rice cultivars and N application rates. Plant N accumulation (PNA) and canopy spectral vegetation indices (VIs) were measured at tillering and jointing stages with two spectrometers, i.e., GreenSeeker (an active multispectral sensor containing 780 and 660 nm wavelengths) and crop growth monitoring and diagnosis apparatus (CGMD, a passive multispectral sensor containing 810 and 720 nm wavelengths). The VI-based models of PNA were established from a experimental dataset and then validated using an independent dataset. The N topdressing rates for tillering and jointing stages were calculated using the newly developed N spectral diagnosis model and higher yield cultivation experience of double-cropping rice. The results showed that the VIs from two spectrometers were strongly positively correlated with PNA at both growth stages, with the model performance for tillering or jointing stages was better than that for the early growth stages. The exponential equation of normalized difference vegetation index (NDVI(780,660)) from GreenSeeker could be used to estimate PNA with a determination coefficient (R2) in the range of 0.92-0.94, the root mean square error (RMSE), relative root mean square error (RRMSE) and correlation coefficient (r) of model validation in the range of 3.09-5.96 kg·hm-2, 5.8%-18.5% and 0.92-0.98, respectively. The linear equation of difference vegetation index (DVI(810,720)) from CGMD could be used to estimate PNA with a R2 in the range of 0.90-0.93, the RMSE, RRMSE and r of model validation in the range of 3.71-6.33 kg·hm-2, 11.7%-14.3% and 0.93-0.96, respectively. The recommended N topdressing rate with CGMD was higher than that with GreenSeeker. Compared with conventional farmer's plan, the precision N application plan reduced N fertilizer application rate by 5.5 kg·hm-2, while N agronomic efficiency and net income was improved by 0.8% and 128 yuan·hm-2, respectively. Application of the spectral monitoring and diagnosis method to guiding fertilization could reduce cost and increase grain yield and net income, and thus had great potential for guiding double-cropping rice production.


Assuntos
Oryza , Agricultura , China , Grão Comestível , Fertilizantes , Nitrogênio
14.
RSC Adv ; 10(61): 37287-37298, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-35521249

RESUMO

Hydrotreatment is an effective upgrading technology for removing contaminants and saturating double bonds. Still, few studies have reported the hydro-upgrading of shale oil, with unusually high sulfur (13200 ppm) content, using the CoMo/Al2O3 catalyst. Here we report an extensive study on the upgrading of shale oil by hydrotreatment in a stirred batch autoclave reactor (500 ml) for sulfur removal and viscosity reduction. From a preliminary optimization of the reaction factors, the best-operating conditions were 400 °C, an initial H2-pressure of 5 MPa, and an agitation rate of 800 rpm, a catalyst-to-oil ratio of 0.1, and a reaction time of 1 h. We could achieve a sulfur removal efficiency of 87.1% and 88.2% viscosity reduction under the optimal conditions. After that, the spent CoMo/Al2O3 was repeatedly used for subsequent upgrading tests without any form of pre-treatment. The results showed an increase in the sulfur removal efficiency with an increase in the number of catalyst runs. Ultimately, 99.5-99.9% sulfur removal from the shale oil was achieved by recycling the spent material. Both the fresh and the spent CoMo/Al2O3 were characterized and analyzed to ascertain their transformation levels by XRD, TEM, TG, XPS, TPD and N2 adsorption analysis. The increasing HDS efficiency is attributed to the continuing rise in the sulfidation degree of the catalyst in the sulfur-rich shale oil. The light fraction component in the liquid products (IBP-180 °C) was 30-37 vol% higher than in the fresh shale oil. The product oil can meet the sulfur content requirement of the national standard marine fuel (GB17411-2015/XG1-2018) of China.

15.
J Photochem Photobiol B ; 202: 111680, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31810038

RESUMO

Tissue engineering and stem cell rehabilitation are the hopeful aspects that are being investigated for the management of Myocardial Infarction (MI); cardiac patches have been used to start myocardial rejuvenation. In this study, we engineered p-phenylenediamine surface functionalized (modif-CQD) into the Silk fibroin/PLA (SF/PLA) nanofibrous bioactive scaffolds with improved physico-chemical abilities, mechanical and cytocompatibility to cardiomyocytes. The micrograph results visualized the morphological improved spherical modif-CQD have been equivalently spread throughout the SF/PLA bioactive cardiac scaffolds. The fabricated CQD@SF/PLA nanofibrous bioactive scaffolds were highly porous with fully consistent pores; effectively improved young modulus and swelling asset for the suitability and effective implantation efficacy. The scaffolds were prepared with rat cardiomyocytes and cultured for up to 7 days, without electrical incentive. After 7 days of culture, the scaffold pores all over the construct volume were overflowing with cardiomyocytes. The metabolic activity and viability of the cardiomyocytes in CQD@SF/PLA scaffolds were significantly higher than cardiomyocytes in Silk fibroin /PLA scaffolds. The integration of CQD also influenced greatly and increases the expression of cardiac-marker genes. The results of the present investigations evidently recommended that well-organized cardiac nanofibrous scaffold with greater cardiac related mechanical abilities and biocompatibilities for cardiac tissue engineering and nursing care applications.


Assuntos
Fibroínas/química , Nanofibras/química , Pontos Quânticos/química , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Carbono/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Raios Infravermelhos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Nanofibras/toxicidade , Poliésteres/química , RNA Mensageiro/metabolismo , Ratos , Troponina C/genética , Troponina C/metabolismo
16.
Small ; 15(11): e1805325, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30735305

RESUMO

Nitrogen (N)-doped carbons are potential nonprecious metal catalysts to replace Pt for the oxygen reduction reaction (ORR). Pyridinic-N-C is believed to be the most active N group for catalyzing ORR. In this work, using zinc phthalocyanine as a precursor effectively overcomes the serious loss of pyridinic-N, which is commonly regarded as the biggest obstacle to catalytic performance enhancement upon adopting a second pyrolysis process, for the preparation of a 3D porous N-doped carbon framework (NDCF). The results show only ≈14% loss in pyridinic-N proportion in the Zn-containing sample during the second pyrolysis process. In comparison, a loss of ≈72% pyridinic-N occurs for the non-Zn counterpart. The high pyridinic-N proportion, the porous carbon framework produced upon NaCl removal, and the increased mesoporous defects in the second pyrolysis process make the as-prepared catalyst an excellent electrocatalyst for ORR, exhibiting a half-wave potential (E1/2 = 0.88 V) up to 33 mV superior to state-of-the-art Pt/C and high four-electron selectivity (n > 3.83) in alkaline solution, which is among the best ORR activities reported for N-doped carbon catalysts. Furthermore, only ≈18 mV degradation in E1/2 occurs after an 8000 cycles' accelerating stability test, manifesting the outstanding stability of the as-prepared catalyst.

17.
Molecules ; 23(10)2018 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-30249066

RESUMO

An easy access to a series of previously unreported heterodinuclear Pd-Ln compounds, Pd-bpydc-La, Pd-bpydc-Ce and Pd-bpydc-Nd (bpydc = 2,2'-bipyridine-5,5'-dicarboxylate) has been developed. The Pd-Ln hybrid networks were effectively applied as catalysts in Suzuki⁻Miyaura C-C cross-coupling reactions of 4-bromoanisole and 4-bromobenzonitrile with phenylboronic acid, under mild conditions. A systematic investigation revealed Pd-bpydc-Nd as the most active catalyst. In all cases, reaction yields varied with the base, catalyst loading and substantially augmented with temperature (from 30 to 60 °C). Substituent effects were operative when changing from 4-bromoanisole to 4-bromobenzonitrile. The key role played by the lanthanides, aromatic substrate and base, in modulating the Pd-catalytic cycle has been highlighted. Importantly, the new catalysts proved to be stable in air and vs. functionalities and are quite efficient in Suzuki⁻Miyaura carbon-carbon bond formation conducted in protic solvents.


Assuntos
Elementos da Série dos Lantanídeos/química , Paládio/química , Catálise , Cristalografia por Raios X , Estrutura Molecular , Temperatura
18.
Trials ; 19(1): 130, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29467025

RESUMO

BACKGROUND: No ideal blood pressure (BP) range has been scientifically determined for acute stroke, and no studies on BP management have been carried out for patients with severe stroke. This trial aims to investigate whether individualized lowering of elevated BP would improve the outcome in patients with severe stroke. METHODS/DESIGN: The CHASE trial is a multicenter, randomized, controlled study. A total of 500 adult patients with acute severe stroke will be enrolled in 18 study sites in China and randomized to individualized BP lowering (10-15% reduction from admission level) or guideline-recommended BP lowering. The primary outcome measurement is the proportion of participants with a poor outcome (modified Rankin Scale ≥ 3) at day 90 of enrollment. Secondary outcomes include disability at hospital discharge and the ability of activities of daily living at day 90 of enrollment. The relationship between intervention and the primary outcome will be analyzed using multivariate logistic regression adjusted for study site, demographics, and baseline characteristics. DISCUSSION: The CHASE trial will be the first study to explore the optimum BP management for acute severe stroke. This trial potentially offers a strong argument for individualized target for lowering elevated BP in patients with severe stroke. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02982655 . Registered on 30 November 2016.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Atividades Cotidianas , Anti-Hipertensivos/efeitos adversos , China , Avaliação da Deficiência , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Método Simples-Cego , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
19.
RSC Adv ; 8(53): 30387-30395, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35546860

RESUMO

A series of CuO-ZnO-Al2O3/HZSM-5 hybrid catalysts with different Cu/Zn ratios and disparate Al2O3 doping were prepared and characterized by XRD, BET, H2-TPR, NH3-TPD and XPS techniques. The optimal Cu/Zn ratio is 7 : 3, and the introduction of a suitable amount of Al2O3 to form hybrid catalysts increased the BET specific area and micropore volume, facilitated the CuO dispersion, decreased the CuO crystallite size, increased the interaction between CuO and ZnO, enhanced the number of weak acid sites, altered the copper chemical state and improved the catalytic performance consequently. The highest CO2 conversion, DME selectivity and DME yield of 27.3%, 67.1% and 18.3%, respectively, were observed over the CZA7H catalyst. The suitable temperature of 260 °C and the appropriate space velocity of 1500 h-1 for one-step synthesis of dimethyl ether (DME) from carbon dioxide (CO2) hydrogenation were also investigated. The 50 h stability of the CZA7H catalyst was also tested.

20.
RSC Adv ; 8(57): 32533-32537, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-35547699

RESUMO

Phosphorus pentoxide (P2O5)/metal chloride mixtures could significantly improve 5-HMF yield and selectivity for the catalytic conversion of fructose under mild conditions, whereas neither P2O5 nor tested metal chloride alone gave reasonable performances. A maximum 5-HMF yield of 75% with ∼85% selectivity could be achieved within 30 min at 80 °C.

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