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1.
J Sep Sci ; 45(22): 4128-4140, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36099359

RESUMO

Solid phase extraction combined with ultra-performance liquid chromatography-tandem mass spectrometry was developed for the simultaneous determination of 31 endocrine-disrupting chemicals in fish plasma. The strong anion exchange/primary-secondary amine cartridge and the mixed cation exchange cartridge were used in tandem instead of using a single mixed cation exchange cartridge for sample purification. Suitable eluents were selected for each of the two cartridges: 4.5% ammonia/acetonitrile solution for cartridges in tandem and acetone:n-hexane (V:V = 3:7) for the strong anion exchange/primary-secondary amine cartridge alone. With this optimized Solid phase extraction method, the recoveries of 31 endocrine disrupting chemicals were between 43.0% and 131.3%, the method detection limits were 0.45 to 1.35 ng/ml, and the limits of quantitation were 1.50-4.50 ng/ml. The innovative pretreatment method that connects two cartridges in tandem is well positioned to mitigate the matrix effects of fish plasma, thereby improving the accuracy of multiclass endocrine-disrupting chemicals determination. The significance of this method is to facilitate the application of the fish plasma model for the environmental risk assessment of endocrine-disrupting chemicals.


Assuntos
Disruptores Endócrinos , Animais , Disruptores Endócrinos/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Extração em Fase Sólida/métodos , Peixes , Aminas , Cromatografia Líquida de Alta Pressão/métodos
2.
J AOAC Int ; 104(3): 818-826, 2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-33450009

RESUMO

BACKGROUND: Currently, although Inula nervosa Wall is substantially investigated, little is understood about blossoms of Inula nervosa Wall (BINW). OBJECTIVE: In this work, we systematically investigated the antioxidant activity of the extract from BINW by various standard assays including 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical ability, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) di-ammonium salt radical cation (ABTS), and ferric reducing antioxidant potential (FRAP). METHODS: Chemical compounds were tentatively identified through an UHPLC-QTOF-MS system. Furthermore, the contents of nine compounds were detected with UHPLC method coupled with photodiode array (PDA) detector. By carefully analyzing the quantitative data via clusters analysis and principal component analysis (PCA). RESULTS: Forty-six compounds were tentatively identified, and our results showed that nine compound samples in 21 batches of BINW collected from different areas could be differentiated and analyzed by a heatmap visualization. In addition, the contents of nine compounds (flavonoids, phenolic acids) exhibited a total of higher amounts and better antioxidant activities from Yunnan than those from the other three origins. CONCLUSIONS: Our study not only developed a powerful platform to explain the difference between traditional Chinese medicines species that are closely related through the chemometric and chemical profiling, but also presented a useful method to establish quality criteria of BINW with multiple origins. HIGHLIGHTS: To characterize the BINW in detail, we not only performed DPPH, FRAP, and ABTS assays to investigate its antioxidant activity, but also established UHPLC-QTOF-MS/MS- and UHPLC-PDA-based methods to comprehensively identify and qualitatively analyze its components.


Assuntos
Inula , Antioxidantes , China , Flores , Extratos Vegetais , Espectrometria de Massas em Tandem
3.
Biomed Chromatogr ; 32(8): e4239, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29524341

RESUMO

Glechomae Herba (GH) is rich in bioactive phenolic constituents and is widely used for treatment of cholelithiasis, urolithiasis and dropsy. The simultaneous determination of phenolic constituents in GH from different geographical origins is significant for authentication and quality control purposes. In this study, we developed a strategy integrating targeted analysis and chemometric methods for quality evaluation and discrimination of GH from different geographical origins. Firstly, an accurate and reliable liquid chromatography-tandem mass spectrometry method was developed for simultaneous quantification of 15 phenolic constituents in GH from different geographical origins. The established method was well validated in terms of desirable specificity, linearity, precision and accuracy. Secondly, the quantitative data were subjected to principal component analysis and orthogonal partial least squares discriminant analysis. Thirdly, a heatmap visualization was employed for clarifying the distribution of 15 phenolic compounds in GH from different geographical origins. These results indicated that GH samples from Shandong province obviously differ from those from other provinces in the content of bioactive phenolic constituents. Collectively, the proposed platform might be a suitable tool for quality evaluation and discrimination of GH from different geographical origins, providing promising perspectives in tracking the formulation processes of traditional Chinese medicine products.


Assuntos
Cromatografia Líquida/métodos , Medicamentos de Ervas Chinesas/química , Fenóis/análise , Espectrometria de Massas em Tandem/métodos , Lamiaceae/química , Modelos Lineares , Análise de Componente Principal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
J Pharm Biomed Anal ; 154: 236-244, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29558724

RESUMO

The Chimonanthus nitens Oliv. leaf (CNOL). is a widely used traditional Chinese medicine (TCM) used for treating colds and influenza. In the present study, a comprehensive strategy integrating multiple chromatographic analysis and chemometric methods was firstly proposed for structural characterization and discrimination of CNOL from different geographical origins. It consists of three steps: Firstly, the ultra-high-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UHPLC-QTOF-MS/MS) method was applied for comprehensive profiling of characterization constituents in CNOL by high-resolution diagnostic product ions/neutral loss filtering, and a total of 40 constituents were identified. Secondly, chemical fingerprints were established by HPLC coupled with photodiode array detector (PDA), and similarity analyses were calculated based on nineteen common characteristic peaks. Subsequently, the nine major constituents, including coumarins, flavonoids, and phenolic acids were quantified, and the quantitative data further analyzed by principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLS-DA). Thirdly, a hot map visualization was conducted for clarifying the distribution of major compounds among different geographical origins. Also, nine constituents detected could be used as chemical markers for discrimination of CNOL from different provinces. Collectively, these results indicated that our proposed platform was a powerful tool for chemical profiling and discrimination of herbs with multiple botanical origins, providing promising perspectives in tracking the formulation process of TCMs products.


Assuntos
Calycanthaceae/química , Medicamentos de Ervas Chinesas/química , Folhas de Planta/química , Cromatografia Líquida de Alta Pressão/métodos , Cumarínicos/química , Análise Discriminante , Flavonoides/química , Hidroxibenzoatos/química , Medicina Tradicional Chinesa/métodos , Análise de Componente Principal/métodos , Espectrometria de Massas em Tandem/métodos
5.
Acta Cardiol Sin ; 33(4): 353-361, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29033506

RESUMO

BACKGROUND: Previous studies have shown that the use of fractional flow reserve (FFR) in addition to angiography significantly reduced the rate of all major adverse cardiovascular events (MACE). However, this practice has not been widely accepted and limited outcome data exist about FFR-guided percutaneous coronary intervention (PCI) in Taiwan. The aim of the present study was to evaluate the possible impact of FFR-guided PCI in coronary stenoses of intermediate severity. METHODS: We performed a retrospective case-control study on 443 cases of intermediate coronary stenoses in 206 patients recruited from our computerized database. The study patients were divided into two groups: the FFR group (n = 101) and the angiography group (n = 105), matched with age, gender, clinical and angiographic lesion characteristics. In the angiography group, the indicated lesions had been treated with PCI by angiographic or anatomical assessment, whereas those patients in the FFR group underwent PCI of indicated lesions only if the FFR was < 0.80. The primary end point was the MACE rate regarding death, nonfatal myocardial infarction (MI), and target vessel failure at a mean follow-up of 418 days. RESULTS: The MACE rate was similar in both groups (6% in the angiography group and 3% in the FFR group, p = 0.06). However, FFR-guided PCI strategy prevented unnecessary revascularization in up to 75% of patients, and markedly reduced costs of the index hospitalization. Moreover, multivariate analysis found that the use of drug-eluting stent and statin therapy, and the presence of family history of premature coronary artery disease and periprocedural MI are independent predictors of clinical outcomes. CONCLUSIONS: FFR-guided intervention, compared to angiography-guided intervention for Taiwanese patients with coronary stenoses of intermediate severity, achieved similar clinical outcomes and provided cost-savings.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(6): 1497-500, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26601354

RESUMO

Oxygen concentration is an important monitoring parameter in industrial process. Wavelength modulation spectroscopy of tunable diode laser absorption spectroscopy (TDLAS) was used to measure concentration of oxygen gas in industrial process by online monitoring. In this paper, we use the characteristic absorption peak of Oxygen at 760 nm to measure the oxygen concentration. Because of the strong coherence of laser, the detection sensitivity of TDLAS is severely restricted by optical interference noise. Especially at low concentrations, there is larger error by extraction signal in the absorption peak waveform because of the background fluctuation caused by optical interference. In response to this situation, Levenberg-Marquardt nonlinear fitting algorithm was proposed, and the use of the absorption line-derivative form of Lorenz line to fit the second harmonic signal and to extract the peak amplitude. On the other hand, Levenberg-Marquardt nonlinear fitting method needs a large amount of calculation. In order to develop the TDLAS analyzer can achieve real-time monitoring of the site, we use the C28 series of DSQ for data processing which support floating-point arithmetic, and the instrument achieve real-time monitoring capabilities in industrial process. Experimental results show that the algorithm can effectively extract the absorption peak characteristic value of the 2nd harmonic signal and overcome the background noise, The ratio of calculated by algorithm to actual oxygen concentration is nearly 1.01, the linear error of the concentration measurement is 1.18%.

7.
J Asian Nat Prod Res ; 17(4): 352-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25465438

RESUMO

Two new compounds 5-[4'-(4″-hydroxybenzyl)-3'-hydroxybenzyloxymethyl]-furan-2-carbaldehyde (1) and 5-[4'-(4″-hydroxybenzyl)-3'-hydroxybenzyl]-furan-2-carbal-dehyde (2), together with two known 5-(4-hydroxbenzyloxymethyl)-furan-2-carbaldehyde] (3) and 5-(hydroxymethyl)-2-furaldehyde (4), were isolated from the rhizome of Gastrodia elata. Their structures were elucidated by spectroscopic analysis and comparison of their spectral data with those reported previously. All compounds exhibited weak or no cytotoxicity against human colon carcinoma cell line (HT-29) and human chronic myelogenous leukemia cell line (K-562).


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Furaldeído/análogos & derivados , Gastrodia/química , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Furaldeído/química , Furaldeído/isolamento & purificação , Furaldeído/farmacologia , Células HT29 , Humanos , Estrutura Molecular , Fenóis/química , Rizoma/química
8.
Cardiology ; 118(4): 207-16, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21701170

RESUMO

OBJECTIVES: Endothelin-1 (ET-1) induces cardiac hypertrophy, whereas adiponectin may elicit protective effects in the vasculature and myocardium. We therefore evaluated the relationship between plasma ET-1 and adiponectin levels in heart failure (HF) patients, and the association between adiponectin expression and ET-1-induced hypertrophy of human cardiomyocytes (HCM) in vitro. METHODS: One hundred seventeen patients with chronic HF were enrolled into this study. A group of 7 patients with end-stage HF undergoing heart transplantation was included in the histopathological study. Baseline clinical evaluations and laboratory measurements were performed. HCM cultures were studied to investigate the effect of ET-1 on cell size and adiponectin expression. RESULTS: Plasma ET-1, adiponectin, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) increased with the severity of HF. Higher New York Heart Association functional class, plasma ET-1, adiponectin, and NT-proBNP levels were significant predictors of adverse outcomes in these patients. The myocardial expression of adiponectin was significantly higher in the recipient hearts of patients undergoing emergency or urgent heart transplantation. In cell culture, ET-1 significantly increased cell size and adiponectin expression in HCM. CONCLUSIONS: Adiponectin was significantly elevated in HF and was significantly associated with ET-1. The study provides a basis for further investigation of ET-1 and adiponectin modulation as a therapeutic strategy for ventricular remodeling in HF.


Assuntos
Adiponectina/sangue , Endotelina-1/sangue , Insuficiência Cardíaca/sangue , Miocárdio/metabolismo , Índice de Massa Corporal , Cardiomegalia/metabolismo , Tamanho Celular , Células Cultivadas , Feminino , Insuficiência Cardíaca/diagnóstico , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Prognóstico
9.
J Chromatogr A ; 1051(1-2): 85-94, 2004 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-15532559

RESUMO

The migration behavior of cationic solutes and influences of the interactions of cationic solutes with sodium dodecyl sulfate (SDS) on the formation of micelles and its critical micelle concentration (CMC) were investigated by capillary electrophoresis at neutral pH. Catecholamines and structurally related compounds, including epinephrine, norepinephrine, dopamine, norephedrine, and tyramine, which involve different extents of hydrophobic, ionic and hydrogen-bonding interactions with SDS surfactant, are selected as cationic solutes. The dependence of the effective electrophoretic mobility of cationic solutes on the concentration of surfactant monomers in the premicellar region provides direct evidence of the formation of ion-pairs between cationic solutes and anionic dodecyl sulfate monomers. Three different approaches, based on the variations of either the effective electrophoretic mobility or the retention factor as a function of surfactant concentration in the premicellar and micellar regions, and the linear relationship between the retention factor and the product of a distribution coefficient and the phase ratio, were considered to determine the CMC value of SDS micelles. The suitability of the methods used for the determination of the CMC of SDS with these cationic solutes was discussed. Depending on the structures of cationic solutes and electrophoretic conditions, the CMC value of SDS determined varies in a wide concentration range. The results indicate that, in addition to hydrophobic interaction, both ionic and hydrogen-bonding interactions have pronounced effects on the formation of SDS micelles. Ionic interaction between cationic solutes and SDS surfactant stabilizes the SDS micelles, whereas hydrogen-bonding interactions weakens the solubilization of the attractive ionic interaction. The elevation of the CMC of SDS depends heavily on hydrogen-bonding interactions between cationic solutes and SDS surfactant. Thus, the CMC value of SDS is remarkably elevated with catecholamines, such as epinephrine and norepinephrine, as compared with norephedrine. In addition, the effect of methanol content in the sample solution of these cationic solutes on the CMC of SDS was also examined.


Assuntos
Eletroforese Capilar/métodos , Dodecilsulfato de Sódio/química , Cátions , Ligação de Hidrogênio , Neurotransmissores/química
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