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1.
Small Methods ; 6(1): e2101186, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35041283

RESUMO

Interfacial microenvironment modulation has been proven to be a promising route to fabricate highly efficient catalysts. In this work, the lattice defect-rich NiS2 /MoS2 nanoflakes (NMS NFs) electrocatalysts are successfully synthesized by a simple strategy. Benefiting from the abundant lattice defects and modulated interfacial microenvironment between NiS2 and MoS2 , the prepared NMS NFs show superior catalytic activity for water splitting. Particularly, the optimized NMS NFs (the molar ratio of Ni:Mo = 5:5) exhibit remarkable catalytic activity toward overall water splitting with a voltage of 1.60 V at 10 mA cm-2 in alkaline media, which is lower than that of the noble-metal-based electrocatalysts (1.68 V at 10 mA cm-2 ). The NMS NFs electrocatalysts also show exceptional long-term stability (>50 h) for overall water splitting. The density functional theory results demonstrate that the injection of NiS2 into MoS2 can greatly optimize the catalytic kinetics and reduce the energy barrier for hydrogen/oxygen evolution reactions. The work does not only offer a promising candidate for a highly efficient water splitting electrocatalyst but also highlights that interfacial microenvironment modulation is a potential strategy to optimize the catalytic kinetics.

2.
ACS Appl Mater Interfaces ; 13(15): 17978-17987, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33821600

RESUMO

Functional separators, which are chemically modified and coated with nanostructured materials, are considered an effective and economical approach to suppressing the shuttle effect of lithium polysulfide (LiPS) and promoting the conversion kinetics of sulfur cathodes. Herein, we report cobalt-aluminum-layered double hydroxide quantum dots (LDH-QDs) deposited with nitrogen-doped graphene (NG) as a bifunctional separator for lithium-sulfur batteries (LSBs). The mesoporous LDH-QDs/NG hybrids possess abundant active sites of Co2+ and hydroxide groups, which result in capturing LiPSs through strong chemical interactions and accelerating the redox kinetics of the conversion reaction, as confirmed through X-ray photoelectron spectroscopy, adsorption tests, Li2S nucleation tests, and electrokinetic analyses of the LiPS conversion. The resulting LDH-QDs/NG hybrid-coated polypropylene (LDH-QDs/NG/PP) separator, with an average thickness of ∼17 µm, has a high ionic conductivity of 2.67 mS cm-1. Consequently, the LSB cells with the LDH-QDs/NG/PP separator can deliver a high discharge capacity of 1227.48 mAh g-1 at 0.1C along with a low capacity decay rate of 0.041% per cycle over 1200 cycles at 1.0C.

3.
Sci Rep ; 11(1): 7383, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795788

RESUMO

Dual antiplatelet therapy (DAPT) with clopidogrel plus aspirin within 48 h of acute minor strokes and transient ischemic attacks (TIAs) has been indicated to effectively reduce the rate of recurrent strokes. However, the efficacy of clopidogrel has been shown to be affected by cytochrome P450 2C19 (CYP2C19) polymorphisms. Patients carrying loss-of-function alleles (LoFAs) at a low risk of recurrence (ESRS < 3) cannot benefit from clopidogrel plus aspirin at all and may have an increased bleeding risk. In order to optimize antiplatelet therapy for these patients and avoid the waste of medical resources, it is important to identify the subgroups that genuinely benefit from DAPT with clopidogrel plus aspirin through CYP2C19 genotyping. This study sought to assess the cost-effectiveness of CYP2C19 genotyping to guide drug therapy for acute minor strokes or high-risk TIAs in China. A decision tree and Markov model were constructed to evaluate the cost-effectiveness of CYP2C19 genotyping. We used a healthcare payer perspective, and the primary outcomes included quality-adjusted life years (QALYs), costs and the incremental cost-effectiveness ratio (ICER). Sensitivity analyses were performed to evaluate the robustness of the results. CYP2C19 genotyping resulted in a lifetime gain of 0.031 QALYs at an additional cost of CNY 420.13 (US$ 59.85), yielding an ICER of CNY 13,552.74 (US$ 1930.59) per QALY gained. Probabilistic sensitivity analysis showed that genetic testing was more cost-effective in 95.7% of the simulations at the willingness-to-pay threshold of CNY 72,100 (GDP per capita, US$ 10,300) per QALY. Therefore, CYP2C19 genotyping to guide antiplatelet therapy for acute minor strokes and high-risk TIAs is highly cost-effective in China.


Assuntos
Citocromo P-450 CYP2C19/genética , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/genética , Inibidores da Agregação Plaquetária/farmacologia , Alelos , China , Clopidogrel/farmacologia , Simulação por Computador , Análise Custo-Benefício , Árvores de Decisões , Método Duplo-Cego , Genótipo , Humanos , Ataque Isquêmico Transitório/economia , Cadeias de Markov , Neurociências , Placebos , Inibidores da Agregação Plaquetária/economia , Polimorfismo Genético , Probabilidade , Anos de Vida Ajustados por Qualidade de Vida , Risco
4.
Adv Mater ; 31(34): e1803444, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31012183

RESUMO

Electrochemical sodium storage and capture are considered an attractive technology owing to the natural abundance, low cost, safety, and cleanness of sodium, and the higher efficiency of the electrochemical system compared to fossil-fuel-based counterparts. Considering that the sodium-ion chemistry often largely deviates from the lithium-based one despite the physical and chemical similarities, the architecture and chemical structure of electrode materials should be designed for highly efficient sodium storage and capture technologies. Here, the rational design in the structure and chemistry of carbon materials for sodium-ion batteries (SIBs), sodium-ion capacitors (SICs), and capacitive deionization (CDI) applications is comprehensively reviewed. Types and features of carbon materials are classified into ordered and disordered carbons as well as nanodimensional and nanoporous carbons, covering the effect of synthesis parameters on the carbon structure and chemistry. The sodium storage mechanism and performance of these carbon materials are correlated with the key structural/chemical factors, including the interlayer spacing, crystallite size, porous characteristics, micro/nanostructure, morphology, surface chemistry, heteroatom incorporation, and hybridization. Finally, perspectives on current impediment and future research directions into the development of practical SIBs, SICs, and CDI are also provided.

5.
Int J Clin Pharm ; 40(5): 1010-1018, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29777329

RESUMO

Background Theophylline has a narrow therapeutic range and large interindividual variability in blood levels, so a thorough understanding of its pharmacokinetic characteristics is essential. Population pharmacokinetic (PPK) approaches could achieve it and many PPK studies of theophylline have been reported in infants. However, none was conducted in Chinese adults and none has explored the effect of CYP1A2 genotypes on the PPK characteristics of theophylline in adults. Objective To evaluate the PPK characteristics of theophylline and to assess the possible influence of covariates, including CYP1A2 genotypes, on theophylline clearance in Chinese adult patients. Setting The study is conducted at the department of respiration in Zhujiang Hospital, Guangzhou, China. Methods Theophylline concentrations were obtained from eligible patients and were measured by high performance liquid chromatography. The polymorphisms of - 3860G > A, - 163C > A, C5347T (CYP1A2*1B) and G-3113A were genotyped using a direct sequencing method. Then, CYP1A2 genotypes, age, fat-free mass (FFM) and other covariates were used to develop a PPK model by NONMEM software. Bootstrap analysis was used to asses the accuracy and prediction of the PPK model. Main outcome measure The concentration and clearance of theophylline. Results A total of 134 theophylline concentrations from 95 patients were obtained. The final model was as follows: CL/F(L/h) = 4.530 × (FFM/56.1)0.75 × 0.713CYP1A2*1B, the inter-individual variability in clearance/bioavailability (CL/F) was 44.0%, and the residual variability was 9.8%. The final model was proved to be reliable by bootstrap analysis. Conclusion Theophylline clearance was significantly associated with FFM and CYP1A2*1B genotypes in Chinese adult patients.


Assuntos
Povo Asiático , Asma/sangue , Broncodilatadores/farmacocinética , Citocromo P-450 CYP1A2 , Doença Pulmonar Obstrutiva Crônica/sangue , Teofilina/farmacocinética , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/genética , Asma/tratamento farmacológico , Asma/genética , Broncodilatadores/administração & dosagem , Citocromo P-450 CYP1A2/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/genética , Teofilina/administração & dosagem , Adulto Jovem
6.
BMC Neurosci ; 19(1): 3, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29390963

RESUMO

BACKGROUND: Real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) is a critical tool for evaluating the levels of mRNA transcribed from genes. Reliable RT-qPCR results largely depend on normalization to suitable reference genes. Middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation/reoxygenation (OGD/R) are models that are commonly used to study ischemic stroke. However, the proper reference genes for RNA analysis in these two models have not yet been determined. RESULTS: In this study, we evaluated the expression levels of six candidate housekeeping genes and selected the most suitable reference genes for RT-qPCR analyses of the cortices of MCAO mice and OGD/R-injured N2a cells. Four software programs, geNorm, NormFinder, BestKeeper and RefFinder, were used to validate the stabilities of the candidate reference genes. The results revealed that HPRT and 18S were the most stable reference genes in the cortices of MCAO mice and that ß-actin and cyclophilin were the most stable reference genes in the OGD/R-injured N2a cells; in contrast, GAPDH and Sdha were the least stable genes in the cortices of MCAO mice and the OGD/R-injured N2a cells, respectively. Moreover, a combination of HPRT, 18S and cyclophilin was most suitable for normalization in analyses of the cortices of MCAO mice, and a combination of ß-actin, cyclophilin, GAPDH, and 18S was most suitable for analyses of the OGD/R-injured N2a cells. CONCLUSIONS: This study provides appropriate reference genes for further RT-qPCR analyses of in vivo and in vitro ischemic stroke and demonstrates the necessity of validating reference genes for RNA analyses under variable conditions.


Assuntos
Isquemia Encefálica/genética , Perfilação da Expressão Gênica , Expressão Gênica/genética , Reação em Cadeia da Polimerase em Tempo Real , Acidente Vascular Cerebral/genética , Animais , Linhagem Celular , Expressão Gênica/fisiologia , Camundongos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos
7.
J Thorac Dis ; 7(4): 644-52, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25973230

RESUMO

BACKGROUND: Inhaled corticosteroids (ICSs) are widely used in combination with second controller medications in the management of asthma in adults and children. There lacks a systematic comparison between addition of leukotriene receptor antagonists (LTRAs) and theophylline to ICS. The purpose of this meta-analysis was to evaluate the difference of the efficacy and safety profile of adding either LTRAs or theophylline to ICS in adults and children with symptomatic asthma. METHODS: Randomised controlled trials (RCTs) published prior to November 2014 were acquired through systematically searching and selected based on the established inclusion criteria for publications. The data extracted from the included studies were further analyzed by a meta-analysis. RESULTS: We included eight RCTs, of which six recruited adults and two recruited children aged 5 to 14 years. The primary outcomes were changes in lung function from baseline, including forced expiratory volume in the first second (FEV1) and peak expiratory flow (PEF). Overall, addition of LTRAs led to significantly better morning PEF {mean difference (MD) 16.94 [95% confidence interval (CI): 11.49-22.39] L/min, P<0.01} and FEV1 [MD 0.09 (95% CI: 0.03-0.15) L, P=0.005] as compared to addition of theophylline. There were no differences between the two treatments in terms of evening PEF, adverse events, rescue medication use and asthma exacerbation. CONCLUSIONS: The combination of LTRA and ICS leads to modestly greater improvement in lung function than the combination of theophylline and ICS in the treatment of symptomatic asthma. Long-term trials are required to assess the efficacy and safety of these two therapies.

8.
Int J Clin Exp Med ; 8(1): 212-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25784990

RESUMO

The small-particle inhaled corticosteroid might be a new available way to treat uncontrolled asthma. To evaluate the efficacy and safety of extrafine hydrofluoroalkane-beclomethasone dipropionate (HFA-BDP) versus budesonide (BUD) in patients with asthma, a meta-analysis was performed. A systematic search was made of PubMed, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Clinicaltrials.gov and Ovid, and a hand search of leading respiratory journals. Randomised controlled trials (RCTs) on treatment of asthma for 4 or more weeks with extrafine HFA-BDP, compared with BUD, were reviewed. Five studies involving 949 asthmatic patients met the inclusion criteria. There was no significant difference in FEV1 (SMD=-0.03L, 95% CI -0.15 to 0.10L, I(2)=0%, P=0.70), morning PEF (WMD=0.88 L/min, 95% CI -5.96 to 7.72 L/min, I(2)=0%, P=0.80), evening PEF (WMD=6.32 L/min, 95% CI -1.17 to 13.81 L/min, I(2)=33%, P=0.10) and use of rescue medication (WMD=-0.13, 95% CI -0.31 to 0.06, I(2)=41%, P=0.18) between extrafine HFA-BDP at half of the daily dose and BUD group. Individual studies reported no significant differences in asthma exacerbations and 7-point Asthma Control Questionnaire score (ACQ-7). There were no significant difference in total number of adverse events (OR=1.04, 95% CI 0.78 to 1.38, I(2)=0%, P=0.81) between the two groups. Our meta-analysis demonstrated that extrafine HFA-BDP at half of daily dose is equivalent to BUD in improving lung function and use of rescue medication, without increasing adverse events in patients with asthma. Long-term trials are required to assess the efficacy and safety of extrafine HFA-BDP.

9.
Pharmacoepidemiol Drug Saf ; 23(5): 443-55, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24677603

RESUMO

BACKGROUND: Standard triple therapy for Helicobacter pylori infection fails in up to one quarter of patients. Levofloxacin-based triple therapy may be more efficacious. OBJECTIVE: The aim of this paper was to compare levofloxacin and proton pump inhibitor-based triple therapy with standard triple therapy for H. pylori infection. METHODS: PubMed, Embase, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Google Scholar, and Ovid were systematically searched to identify randomized controlled trials comparing levofloxacin and proton pump inhibitor-based therapy with standard triple therapy in treatment-naive patients with H. pylori infection until August 2013. RESULTS: Ten randomized controlled trials involving 2676 patients (1357 in the levofloxacin group and 1319 in the control group) met the inclusion criteria. The pooled odds ratio by intention-to-treat analysis and by per protocol analysis in the levofloxacin regimen versus standard regimen was 1.28 [95% confidence interval (CI): 0.88-1.85] and 1.23 (95% CI: 0.82-1.84) by the random effects model, respectively. There was no statistical significance of the incidence of total side effects between the groups, but levofloxacin-based therapy was associated with a significant reduction in the incidence of taste disturbance compared with standard third therapy. CONCLUSION: Levofloxacin-based therapy was as safe and effective as triple therapy for H. pylori infection and could be considered as an additional treatment option. However, more rigorous research is required to accurately assess the role of levofloxacin in eradicating H. pylori infection.


Assuntos
Infecções por Helicobacter/tratamento farmacológico , Levofloxacino/uso terapêutico , Inibidores da Bomba de Prótons/uso terapêutico , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Quimioterapia Combinada , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/isolamento & purificação , Humanos , Levofloxacino/administração & dosagem , Levofloxacino/efeitos adversos , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/efeitos adversos
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