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1.
Molecules ; 27(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35056814

RESUMO

The development of low platinum loading hydrogen evolution reaction (HER) catalysts with high activity and stability is of great significance to the practical application of hydrogen energy. This paper reports a simple method to synthesize a highly efficient HER catalyst through coating a highly dispersed PtNi alloy on porous nitrogen-doped carbon (MNC) derived from the zeolite imidazolate skeleton. The catalyst is characterized and analyzed by physical characterization methods, such as XRD, SEM, TEM, BET, XPS, and LSV, EIS, it, v-t, etc. The optimized sample exhibits an overpotential of only 26 mV at a current density of 10 mA cm-2, outperforming commercial 20 wt% Pt/C (33 mV). The synthesized catalyst shows a relatively fast HER kinetics as evidenced by the small Tafel slope of 21.5 mV dec-1 due to the small charge transfer resistance, the alloying effect between Pt and Ni, and the interaction between PtNi alloy and carrier.

2.
Medicine (Baltimore) ; 100(4): e24449, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33530253

RESUMO

ABSTRACT: In patients with diffuse large B-cell lymphoma, MYC combined with Bcl2 and/or Bcl6-based protein expression is called double expression lymphoma (DEL). R-DA-EPOCH program chemotherapy is typically recommended because these patients often have a poor prognosis. Although numerous factors affect survival of patients with DEL, the roles of the tumor biomarker histone methyltransferase G9a (G9a) and the lymphocyte-to-monocyte ratio (LMR) are unknown.We performed a retrospective analysis of data from 51 patients. These patients were newly diagnosed with DEL and treated with R-DA-EPOCH at Taizhou People' s Hospital and Northern Jiangsu People's Hospital between June 2014 and December 2019. Receiver operator characteristic curve results were used to calculate the LMR cutoff value. We used an immunohistochemical analysis to examine G9a expression in DEL tissues. The Kaplan-Meier method was used to determine progression-free survival (PFS) and overall survival (OS) characteristics. Cox proportional-hazards models were constructed for univariate and multivariate analyses to examine the prognostic values of LMRs and G9a in patients with DEL.The cutoff value for LMR was 2.18. The 5-year PFS rate was 35.3%, and the 5-year OS rate was 39.2%. Patients with DEL with lower LMRs and who were G9a-positive predicted inferior PFS and OS. Univariate analysis revealed that patients with elevated LDH levels, high National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI) scores, LMRs ≤2.18, and G9a-positive results had relatively poorer PFS and OS. The multivariate analysis revealed that LMRs ≤2.18 and a G9a-positive result were independent prognostic factors for PFS and OS in patients with DEL treated with R-DA-EPOCH.The study results suggested that peripheral blood LMRs were an important marker for evaluation of prognosis in patients with DEL. High expression of G9a was associated with worse outcomes, indicating that G9a may serve as a prognostic biomarker for patients with DEL who undergo R-DA-EPOCH program chemotherapy.


Assuntos
Antígenos de Histocompatibilidade/sangue , Histona-Lisina N-Metiltransferase/sangue , Linfoma Difuso de Grandes Células B/sangue , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores/sangue , China , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Etoposídeo/uso terapêutico , Feminino , Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Contagem de Linfócitos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Monócitos , Prednisona/uso terapêutico , Modelos de Riscos Proporcionais , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas c-bcl-6 , Estudos Retrospectivos , Vincristina/uso terapêutico
3.
J Chromatogr Sci ; 59(9): 806-812, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-33598689

RESUMO

In order to comprehensively reflect the cigarette quality, a method combining direct injection of diluted sample with high sensitive high-performance liquid chromatography (HPLC)- electrospray (ESI)- quadrupole (Q)- time of flight (TOF)- tandem mass spectrometry (MS/MS) was developed for the identification of major components of cigarette essences (jujube and mulberry extracts). Based on the observed relative molecular mass, MS/MS fragmentation behavior, MS/MS database and related literatures, the components of the jujube extract and mulberry extract were identified. The result shows that the composition of jujube extract and mulberry extract has some similarity. They all mainly contain amino acids, free amino compounds and Maillard reaction products, which are the main constituents of a cigarette essence.


Assuntos
Medicamentos de Ervas Chinesas , Morus , Ziziphus , Cromatografia Líquida de Alta Pressão , Extratos Vegetais , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
4.
J AOAC Int ; 104(3): 712-718, 2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-33252696

RESUMO

BACKGROUND: Some volatile compounds in mouthpiece cigarette adhesive emit irritating odors and affect the taste of smoking cigarettes. Therefore, it is necessary to monitor the volatile compounds in mouthpiece cigarette adhesive. OBJECTIVES: A rapid and simple analytical method of volatile compounds in mouthpiece cigarette adhesive was established. METHODS: In this study, headspace (HS) injection coupled with GC-MS was utilized for qualitative and quantitative analysis. Initially, the volatile compounds in mouthpiece cigarette adhesives were detected by HS-GC-MS, followed by spectrum library retrieval. The detected compounds with the similarity to a spectrum library of more than 85% were further identified by comparing the retention time and mass spectra of the detected volatile compounds and those of the corresponding standard samples. The quantitative analysis of nine identified volatile compounds was performed. RESULTS: Eleven volatile compounds in the mouthpiece cigarette adhesive were accurately identified. The quantitative analytical method of nine volatile compounds in mouthpiece cigarette adhesive was validated to have good linearities (R2 > 0.9932) within the range of 20-5000 ng/g. The detection limits of 9 compounds were within the range of 3.1-147.7 ng/g. The intra- and inter-day relative standard deviations were less than 19.8%. The recoveries of these 9 compounds spiked into mouthpiece cigarette adhesive were 68.1-108.3%. CONCLUSIONS: The proposed method is rapid, simple, and accurate for qualitative and quantitative analysis of volatile compounds in the mouthpiece cigarette adhesive. HIGHLIGHTS: The developed analytical method is expected to be used to monitor volatile compounds in various adhesives.


Assuntos
Produtos do Tabaco , Compostos Orgânicos Voláteis , Adesivos , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/análise
5.
J Chromatogr Sci ; 59(1): 23-29, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33078189

RESUMO

In our present study, the standard chemicals of triacetin were purified by reverse-phase and normal-phase semi-preparative high-performance liquid chromatography (HPLC), and 1H NMR and 13C NMR were employed to determine the purity and structure of triacetin. Moreover, a simple and rapid HPLC-photodiode array (PDA) method was developed to determine the contents of triacetin in 30 batches from different suppliers. The chromatographic separation was performed on a Phenomenex Gemini-NX C18 column (250 × 4.6 mm, 5 µm) using a gradient elution system of water and acetonitrile (contained 0.1% of formic acid) solution with a flow rate of 1.0 mL/min at 30°C at 210 nm. Sample preparation method is rapid and energy efficient, and the obtained sample have a good purity. Validation shows good specificity, linearity (R2 = 0.9995), precision, stability, repeatability (% RSD < 2.80) and the average recovery (99.72%) of triacetin. The content of triacetin in most samples is concentrated in 94-97%. This developed approach is simple, rapid, accurate and can be used to quickly determine the purity and the content of triacetin in plasticizers and filter plugs.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Triacetina/análise , Triacetina/química , China , Cromatografia de Fase Reversa , Contaminação de Medicamentos , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Twin Res Hum Genet ; 23(5): 283-291, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32972470

RESUMO

We explored the genetic architecture of metabolic risk factors of cardiovascular diseases (CVDs) and their clustering in Chinese boys and girls. Seven metabolic traits (body mass index [BMI], waist circumference [WC], systolic blood pressure [SBP], diastolic blood pressure [DBP], total cholesterol [TC], triglyceride [TG], and uric acid [UA]) were measured in a sample of 1016 twins between 8 and 17 years of age, recruited from the Qingdao Twin Registry. Cholesky, independent pathway, and common pathway models were used to identify the latent genetic structure behind the clustering of these metabolic traits. Genetic architecture of these metabolic traits was largely similar in boys and girls. The highest heritability was found for BMI (a2 = 0.63) in boys and TC (a2 = .69) in girls. Three heritable factors, adiposity (BMI and WC), blood pressure (SBP and DBP), and metabolite factors (TC, TG, and UA), which formed one higher-order latent phenotype, were identified. Latent genetic, common environmental, and unique environmental factors indirectly impacted the three factors through one single latent factor. Our results suggest that there is one latent factor influencing several metabolic traits, which are known risk factors of CVDs in young Chinese twins. Latent genetic, common environmental, and unique environmental factors indirectly imposed on them. These results inform strategies for gene pleiotropic discovery and intervening of CVD risk factors during childhood and adolescence.


Assuntos
Doenças Cardiovasculares , Fatores de Risco de Doenças Cardíacas , Adolescente , Pressão Sanguínea , Índice de Massa Corporal , Doenças Cardiovasculares/genética , Criança , China , Análise por Conglomerados , Feminino , Humanos , Masculino , Fatores de Risco , Circunferência da Cintura
7.
Materials (Basel) ; 12(15)2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31349539

RESUMO

Ionic-liquid-functionalized zeolitic imidazolate frameworks (ZIF) were synthesized using the co-ligands of 2-methylimidazole and amine-functionalized ionic liquid during the formation process of frameworks. The resulting ionic-liquid-modified ZIF had a specific surface area of 1707 m2·g-1 with an average pore size of about 1.53 nm. Benefiting from the large surface area and the high solubility of carbon dioxide in ionic-liquid moieties, the synthesized materials exhibited a carbon dioxide adsorption capacity of about 24.9 cm3·g-1, whereas it was 16.3 cm3·g-1 for pristine ZIF at 25 °C under 800 mmHg. The results demonstrate that the modification of porous materials with ionic liquids could be an effective way to fabricate solid sorbents for carbon dioxide adsorption.

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