Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Sci Adv ; 10(16): eadl1856, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640241

RESUMO

Continuous glucose monitoring systems (CGMs) are critical toward closed-loop diabetes management. The field's progress urges next-generation CGMs with enhanced antinoise ability, reliability, and wearability. Here, we propose a coin-sized, fully integrated, and wearable CGM, achieved by holistically synergizing state-of-the-art interdisciplinary technologies of biosensors, minimally invasive tools, and hydrogels. The proposed CGM consists of three major parts: (i) an emerging biochemical signal amplifier, the organic electrochemical transistor (OECT), improving the signal-to-noise ratio (SNR) beyond traditional electrochemical sensors; (ii) a microneedle array to facilitate subcutaneous glucose sampling with minimized pain; and (iii) a soft hydrogel to stabilize the skin-device interface. Compared to conventional CGMs, the OECT-CGM offers a high antinoise ability, tunable sensitivity and resolution, and comfort wearability, enabling personalized glucose sensing for future precision diabetes health care. Last, we discuss how OECT technology can help push the limit of detection of current wearable electrochemical biosensors, especially when operating in complicated conditions.


Assuntos
Técnicas Biossensoriais , Diabetes Mellitus , Humanos , Automonitorização da Glicemia , Glicemia , Monitoramento Contínuo da Glicose , Reprodutibilidade dos Testes , Glucose , Diabetes Mellitus/diagnóstico
2.
J Sep Sci ; 42(7): 1351-1363, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30667161

RESUMO

A sensitive and rapid liquid chromatography with tandem mass spectrometry method has been developed for simultaneous determination of berberine (I), jateorhizine (II), palmatine (III), tetrahydropalmatine (IV), phellodendrine (V), protopine (VI) and columbamine (VII) in rat plasma after oral administration of Phellodendri chinensis cortex extraction. The plasmas were extracted by liquid-liquid extraction. The tandem mass spectrometric detection was performed in the multiple reaction monitoring mode in the positive ionization. The intra- and interday precisions and accuracies were in range from -12.18 to 13.21%. Mean absolute recoveries of all analytes and internal standard were between 78.6 and 98.9%. The seven alkaloids were proven to be stable during sample storage and analysis procedures. The established method was validated and successfully applied to pharmacokinetics study in rat plasma after oral administration of Phellodendri chinensis cortex extract. The t1/2 of palmatine, columbamine, pellodendrine, berberine, tetrahydropalmaine, jatrorrhizine, and protopine were 5.16, 5.96, 7.18, 19.84, 6.28, 7.08, 6.90 h, respectively. The seven compounds could be rapidly absorbed into blood (time for maximal concentration, 1.80-1.93 h). This study could establish a foundation for further research of Phellodendri chinensis cortex and might provide more useful information to guide the clinical usage.


Assuntos
Alcaloides/sangue , Medicamentos de Ervas Chinesas/farmacocinética , Extratos Vegetais/farmacocinética , Administração Oral , Animais , Cromatografia Líquida , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/isolamento & purificação , Masculino , Estrutura Molecular , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
3.
Molecules ; 23(11)2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30445715

RESUMO

A selective and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for the determination of ziyuglycoside I (I), 3ß,19α-dihydroxyurs-12-en-28-oic-acid 28-ß-d-glucopyranosyl ester (II), 3ß-[(α-l-arabinopyranosyl) oxy]-urs-12,18(19)-dien-28-oic acid ß-d-glucopyranosyl ester (III), rosamultin (IV), 1ß-hydroxyeuscaphic acid (V) and alpinoside (VI) in rats after oral administration of Sanguisorba officinalis L. (S. officinalis) extract. The 3ß,19α-dihydroxyurs-12-en-28-oic-acid 28-ß-d-glucopyranosyl ester, 3ß-[(α-l-arabinopyranosyl) oxy]-urs-12,18(19)-dien-28-oic acid ß-d-glucopyranosyl ester, rosamultin, 1ß-hydroxyeuscaphic acid and alpinoside in rat plasma were the first report in the pharmacokinetics study in the present study. The analytes were quantified using the multiple reaction monitoring (MRM) mode with the electrospray ion source in positive electrospray ionization. Plasma was extracted with ethyl acetate via liquid⁻liquid extraction. Bifendate was used as internal standard (IS). The current method was validated for linearity, intra-day and inter-day precisions, accuracy, extraction recovery, matrix effect and stability. The lower limits of quantification of ziyuglycoside I, 3ß,19α-dihydroxyurs-12-en-28-oic-acid 28-ß-d-glucopyranosyl ester, 3ß-[(α-l-arabinopyranosyl) oxy]-urs-12,18(19)-dien-28-oic acid ß-d-glucopyranosyl ester, rosamultin, 1ß-hydroxyeuscaphic acid and alpinoside were 6.1, 4.9, 1.3, 3.8, 1.5 and 5.7 ng/mL, respectively. Intra-day and inter-day precision and the accuracy of the assay were in range from -9.48 to 12.74%. The extraction recoveries of analytes and bifendate (IS) from rat plasma ranged from 77.17% to 92.48%. Six compounds could be rapidly absorbed into blood (Tmax, 0.58⁻1.58 h), and then eliminated relatively slowly (t1/2, 6.86⁻11.63 h). The pharmacokinetic results might contribute to further guide the clinical application of S. officinalis.


Assuntos
Cromatografia Líquida de Alta Pressão , Extratos Vegetais/farmacocinética , Sanguisorba/química , Espectrometria de Massas em Tandem , Triterpenos/farmacocinética , Administração Oral , Animais , Estabilidade de Medicamentos , Masculino , Estrutura Molecular , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Reprodutibilidade dos Testes , Triterpenos/administração & dosagem , Triterpenos/química
4.
Molecules ; 23(8)2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-30072585

RESUMO

This study has developed a sensitive and simple ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry method for the simultaneous determination of corydaline, dehydrocorydaline, tetrahydropalmatine, protopine, palmatine, tetrahydroberberine, columbamine, berberine, coptisine and berberrubine in beagle dog plasma after the oral administration of the Corydalis yanhusuo W.T. Wang and Yuanhuzhitong tablets. Chromatographic separation was achieved on an Agilent Eclipse Plus C18 RRHD column (1.8 µm, 50 × 2.1 mm) using a gradient elution program with a mobile phase consisting of acetonitrile and water containing 0.1% formic acid at a flow rate of 0.3 mL/min. A tandem mass spectrometric detection was conducted by multiple reaction monitoring (MRM) mode via an electrospray ionization source in the positive mode. The calibration curves of all analytes showed good linear (r² > 0.9800). The intra-day and inter-day precisions were less than 15% and the accuracies were within ±15%. The extraction recoveries conformed to the acceptable range. And there was no interference of endogenous substances in the sensitive assay method. All analytes were proven to be stable during sample storage and analysis procedures. The pharmacokinetic study indicated that the Yuanhuzhitong tablets could get a better absorption than Corydalis yanhusuo W.T. Wang.


Assuntos
Alcaloides/administração & dosagem , Alcaloides/sangue , Corydalis/química , Medicamentos de Ervas Chinesas/química , Extratos Vegetais/química , Espectrometria de Massas em Tandem/métodos , Administração Oral , Alcaloides/análise , Alcaloides/química , Animais , Cromatografia Líquida de Alta Pressão , Cães , Limite de Detecção , Análise de Regressão , Espectrometria de Massas por Ionização por Electrospray , Comprimidos
5.
Molecules ; 23(8)2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-30072612

RESUMO

A rapid and sensitive Ultra high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous determination of fourteen alkaloids in beagle dog plasma after a single oral dose of the Corydalis bungeana Turcz (C. bungeana) extract selected bifendate as the internal standard (IS). The plasma samples were preprocessed by liquid-liquid extraction (LLE) with aether before separation on an Agilent SB-C18 column (1.8 µm, 150 × 2.1 mm) using a gradient elution program. The mobile phase consists of 0.2% acetic acid and acetonitrile at the flow rate of 0.3 mL/min. In the positive ion mode, the analytes were detected by multiple reaction monitoring (MRM). The results indicated that calibration curves for fourteen analytes have good linearity (R² = 0.9904). The lower limits of quantification (LLOQ) of fourteen alkaloids and IS were all over 4.87 ng/mL and the matrix effects ranged from 94.08% to 102.76%. The mean extraction recoveries of Quality control samples at low (LQC), medium (MQC) and high (HQC) and IS were all more than 78.03%. The intra- and inter-day precision (R.S.D.%) also met the criterion, at the same time the deviation of assay accuracies (R.E) ranged from -13.70% to 14.40%. The Tmax values of fourteen alkaloids were no more than 1 h. The range of Cmax was from 74.16 ± 8.71 to 2256 ± 255.9 ng/mL. The assay was validated in the light of the regulatory bioanalytical guidelines and proved acceptable, which was successfully applied to a pharmacokinetic study of these compounds in beagle dogs after oral administration of Corydalis bungeana Turcz extract.


Assuntos
Alcaloides/sangue , Alcaloides/farmacocinética , Corydalis/química , Extratos Vegetais/administração & dosagem , Espectrometria de Massas em Tandem/métodos , Administração Oral , Alcaloides/química , Animais , Calibragem , Cromatografia Líquida , Cães , Limite de Detecção , Masculino , Padrões de Referência , Análise de Regressão , Reprodutibilidade dos Testes
6.
J Sep Sci ; 41(10): 2161-2168, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29436170

RESUMO

A sensitive, specific, and accurate ultra high-performance liquid chromatography with electrospray ionization tandem mass spectrometry method was developed and validated for the simultaneous quantification of purpurin, munjistin, mollugin, and alizarin from Qianzhi capsules in rat plasma. Chromatographic separation was performed on an Agilent Eclipse Plus C18 RRHD column with a mobile phase consisting of methanol and 5 mM ammonium acetate/water with gradient elution. The analytes were quantified on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring mode and switching the electrospray ion source polarity with positive electrospray ionization in a single run. Samples were pretreated by liquid-liquid extraction with cyclohexane. The intra- and interday precision and accuracy of the assay were within acceptable ranges. Matrix effects for all of the analytes were between 90.16 and 100.21%. The average recovery ranged from 75.38 to 88.96%. This method was successfully applied to study the pharmacokinetic parameters of the four compounds in rat plasma after oral administration of Qianzhi capsules. Four quinones could be rapidly absorbed into blood (tmax , 0.80-1.93 h) and eliminated relatively slowly (t1/2 , 8.07-11.97 h). The results might be helpful for guiding the clinical application of Qianzhi capsules in the future.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Quinonas/sangue , Quinonas/farmacocinética , Administração Oral , Animais , Cápsulas , Cromatografia Líquida de Alta Pressão , Masculino , Valor Preditivo dos Testes , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
7.
Phytother Res ; 32(4): 667-671, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29368408

RESUMO

Drug resistance represents a major obstacle to improving the overall response and survival of cancer patients. Taxol is one of the most commonly used chemotherapy agents in breast cancer. As with many cancer therapeutic agents, resistance remains a significant problem when using Taxol to treat malignancies. In this study, estrogen receptor positive breast cancer cells MCF-7 were induced Taxol resistance. And Tanshinone IIA combined with Taxol was chosen to treat it. The drugs combination showed additive effect in most drug concentrations. Drug resistance cancer cells showed a higher microtubule associated protein (Tau) expression, which was considered as one of the reasons for Taxol resistance. Tanshinone IIA inhibited the expression of Tau in MCF-7 cells and resulted in higher sensibility of Taxol. Moreover, Tanshinone IIA also showed cytotoxicity to MCF-7, which might be related to its estrogenicity effect. In conclusion, the combination of Tanshinone IIA and Taxol showed higher cytotoxicity to Taxol resistant MCF-7 cells, which might be related to the inhibition of Tau.


Assuntos
Abietanos/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Paclitaxel/uso terapêutico , Abietanos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Paclitaxel/farmacologia
8.
Med Oncol ; 30(1): 467, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23392576

RESUMO

A follow-up study has been carried out to assess the association between MTHFR polymorphisms (SNPs) and overall survival (OS) of colorectal cancer (CRC) patients. Data on 411 CRC patients after surgery were tested for the MTHFR 677C > T and 1298A > C polymorphisms. For MTHFR C677T, patients with CT genotype (HR = 1.17; 95 % CI 0.77-1.80) and those with TT genotype (HR = 1.09; 95 % CI 0.67-1.75) had no statistically significant greater risk of dying than those with wild-type genotype. For MTHFR A1298C, the HRs of AC and CC genotype were 1.09 (95 % CI 0.75-1.59) and 0.79 (95 % CI 0.48-1.29) comparing with AA genotype. In the subgroup, 183 patients received chemotherapy treatment, and the HRs of patients with CT and TT genotype were 0.93 (95 % CI 0.50-1.72) and 0.86 (95 % CI 0.44-1.68) for MTHFR C677T. For A1298C polymorphism, AC genotype (HR = 1.39; 95 % CI 0.81-2.39) and CC genotype (HR = 1.22; 95 % CI 0.75-2.00) did not show significant differences. In conclusions, no significant association was observed between the 677C > T and 1298A > C polymorphisms of MTHFR and the prognosis of colorectal cancer patients with curative resection, including all the subjects and the subgroup of chemotherapy.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Idoso , Povo Asiático/genética , Quimioterapia Adjuvante , China , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Fluoruracila/uso terapêutico , Seguimentos , Frequência do Gene , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA