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1.
Front Neurosci ; 18: 1379988, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784097

RESUMO

The prevalence of synthetic talking faces in both commercial and academic environments is increasing as the technology to generate them grows more powerful and available. While it has long been known that seeing the face of the talker improves human perception of speech-in-noise, recent studies have shown that synthetic talking faces generated by deep neural networks (DNNs) are also able to improve human perception of speech-in-noise. However, in previous studies the benefit provided by DNN synthetic faces was only about half that of real human talkers. We sought to determine whether synthetic talking faces generated by an alternative method would provide a greater perceptual benefit. The facial action coding system (FACS) is a comprehensive system for measuring visually discernible facial movements. Because the action units that comprise FACS are linked to specific muscle groups, synthetic talking faces generated by FACS might have greater verisimilitude than DNN synthetic faces which do not reference an explicit model of the facial musculature. We tested the ability of human observers to identity speech-in-noise accompanied by a blank screen; the real face of the talker; and synthetic talking faces generated either by DNN or FACS. We replicated previous findings of a large benefit for seeing the face of a real talker for speech-in-noise perception and a smaller benefit for DNN synthetic faces. FACS faces also improved perception, but only to the same degree as DNN faces. Analysis at the phoneme level showed that the performance of DNN and FACS faces was particularly poor for phonemes that involve interactions between the teeth and lips, such as /f/, /v/, and /th/. Inspection of single video frames revealed that the characteristic visual features for these phonemes were weak or absent in synthetic faces. Modeling the real vs. synthetic difference showed that increasing the realism of a few phonemes could substantially increase the overall perceptual benefit of synthetic faces.

2.
bioRxiv ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38370798

RESUMO

The prevalence of synthetic talking faces in both commercial and academic environments is increasing as the technology to generate them grows more powerful and available. While it has long been known that seeing the face of the talker improves human perception of speech-in-noise, recent studies have shown that synthetic talking faces generated by deep neural networks (DNNs) are also able to improve human perception of speech-in-noise. However, in previous studies the benefit provided by DNN synthetic faces was only about half that of real human talkers. We sought to determine whether synthetic talking faces generated by an alternative method would provide a greater perceptual benefit. The facial action coding system (FACS) is a comprehensive system for measuring visually discernible facial movements. Because the action units that comprise FACS are linked to specific muscle groups, synthetic talking faces generated by FACS might have greater verisimilitude than DNN synthetic faces which do not reference an explicit model of the facial musculature. We tested the ability of human observers to identity speech-in-noise accompanied by a blank screen; the real face of the talker; and synthetic talking face generated either by DNN or FACS. We replicated previous findings of a large benefit for seeing the face of a real talker for speech-in-noise perception and a smaller benefit for DNN synthetic faces. FACS faces also improved perception, but only to the same degree as DNN faces. Analysis at the phoneme level showed that the performance of DNN and FACS faces was particularly poor for phonemes that involve interactions between the teeth and lips, such as /f/, /v/, and /th/. Inspection of single video frames revealed that the characteristic visual features for these phonemes were weak or absent in synthetic faces. Modeling the real vs. synthetic difference showed that increasing the realism of a few phonemes could substantially increase the overall perceptual benefit of synthetic faces, providing a roadmap for improving communication in this rapidly developing domain.

3.
Stem Cell Rev Rep ; 18(5): 1525-1545, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35344199

RESUMO

Human mesenchymal stem cells (MSCs), also known as mesenchymal stromal cells or medicinal signaling cells, are important adult stem cells for regenerative medicine, largely due to their regenerative characteristics such as self-renewal, secretion of trophic factors, and the capability of inducing mesenchymal cell lineages. MSCs also possess homing and trophic properties modulating immune system, influencing microenvironment around damaged tissues and enhancing tissue repair, thus offering a broad perspective in cell-based therapies. Therefore, it is not surprising that MSCs have been the broadly used adult stem cells in clinical trials. To gain better insights into the current applications of MSCs in clinical applications, we perform a comprehensive review of reported data of MSCs clinical trials conducted globally. We summarize the biological effects and mechanisms of action of MSCs, elucidating recent clinical trials phases and findings, highlighting therapeutic effects of MSCs in several representative diseases, including neurological, musculoskeletal diseases and most recent Coronavirus infectious disease. Finally, we also highlight the challenges faced by many clinical trials and propose potential solutions to streamline the use of MSCs in routine clinical applications and regenerative medicine.


Assuntos
Células-Tronco Adultas , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Adulto , Terapia Baseada em Transplante de Células e Tecidos , Humanos , Medicina Regenerativa
4.
J Anal Toxicol ; 45(7): 633-643, 2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-33201221

RESUMO

After its use for decades in clinical screening, dried blood spots (DBS) have recently received considerable attention for their application in various novel psychoactive substances. The goal of this study was to develop and apply a DBS-based assay for 37 synthetic cathinones and their metabolites. Thirty microliters of whole blood sample after administration was spotted onto Whatman FTA classical cards, dried and extracted, and then analyzed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS). The samples were chromatographed on a Waters Acquity UPLC®HSS T3 column (1.8 µm, 2.1 × 100 mm) and then identically packed defender guard cartridges of a Waters Acquity UPLC®HSS T3 column (1.8 µm, 2.1 × 5 mm, 3/pk). The separation was achieved via solvents of 20 mM ammonium acetate/formic acid 0.1% (A) and acetonitrile (B) at a flow rate of 0.25 mL/min. A tandem MS equipped with positive electrospray ionization mode source was used as the detector. Multiple reaction monitoring with the precursor/product ion combinations was used to quantify each analyte. The linear range of synthetic cathinones in the DBS was 2.0-200 ng/mL, and the lowest limit of quantification was 2.0 ng/mL for some synthetic cathinones and 10 ng/mL for others. The precision and accuracy of the results for the validation samples of the synthetic cathinones were within acceptable criteria. DBS sampling offers the advantages of reduced sample volume and convenient sample storage and shipment. This method can be successfully applied to the quantification of synthetic cathinones.


Assuntos
Alcaloides , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Humanos , Reprodutibilidade dos Testes
5.
iScience ; 23(11): 101754, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33251490

RESUMO

Chondrichthyan (cartilaginous fish) occupies a key phylogenetic position and is important for investigating evolutionary processes of vertebrates. However, limited whole genomes impede our in-depth knowledge of important issues such as chromosome evolution and immunity. Here, we report the chromosome-level genome of white-spotted bamboo shark. Combing it with other shark genomes, we reconstructed 16 ancestral chromosomes of bamboo shark and illustrate a dynamic chromosome rearrangement process. We found that genes on 13 fast-evolving chromosomes can be enriched in immune-related pathways. And two chromosomes contain important genes that can be used to develop single-chain antibodies, which were shown to have high affinity to human disease markers by using enzyme-linked immunosorbent assay. We also found three bone formation-related genes were lost due to chromosome rearrangements. Our study highlights the importance of chromosome rearrangements, providing resources for understanding of cartilaginous fish diversification and potential application of single-chain antibodies.

6.
Talanta ; 209: 120514, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31892045

RESUMO

In this study, sandwich-structured magnetic graphene composites with Zn metal-organic framework layer coated on both two sides (denoted as magG@Zn-MOFs) were synthesized. The composites have large specific surface of 114 m2 g⁻1, uniform porous structure and rapid magnetic separation within 10 s. The magG@Zn-MOFs composites were used for extraction of acarbose in plasma prior to its quantitative analysis by LC-MS/MS. The established method has good linearity (10-1000 ng mL-1), satisfactory recovery (94.3-107.5%), low detection limit (as low as 2.5 ng mL-1), good intra-day precision (RSD 3.5-5.3%) and inter-day precision (RSD 6.3-8.1%). Finally, the method was successfully applied to pharmacokinetic study of acarbose in rats.


Assuntos
Acarbose/sangue , Grafite/química , Estruturas Metalorgânicas/química , Zinco/química , Acarbose/farmacocinética , Animais , Cromatografia Líquida , Óxido Ferroso-Férrico/química , Inibidores de Glicosídeo Hidrolases/sangue , Inibidores de Glicosídeo Hidrolases/farmacocinética , Hipoglicemiantes/sangue , Hipoglicemiantes/farmacocinética , Limite de Detecção , Masculino , Estruturas Metalorgânicas/síntese química , Microesferas , Ratos Sprague-Dawley , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem
7.
J Ginseng Res ; 43(4): 539-549, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31695562

RESUMO

BACKGROUND: 20(S)-Protopanaxadiol (PPD), the aglycone part of 20(S)-protopanaxadiol ginsenosides, possesses antidepressant activity among many other pharmacological activities. It is currently undergoing clinical trial in China as an antidepressant. METHODS: In this study, an ultra-performance liquid chromatography coupled with triple quadrupole time-of-flight mass tandem mass spectrometry method was established to identify the metabolites of PPD in human plasma and urine following oral administration in phase IIa clinical trial. RESULTS: A total of 40 metabolites in human plasma and urine were identified using this method. Four metabolites identified were isolated from rat feces, and two of them were analyzed by NMR to elucidate the exact structures. The structures of isolated compounds were confirmed as (20S,24S)-epoxydammarane-12,23,25-triol-3-one and (20S,24S)-epoxydammarane-3,12,23,25-tetrol. Both compounds were found as metabolites in human for the first time. Upon comparing our findings with the findings of the in vitro study of PPD metabolism in human liver microsomes and human hepatocytes, metabolites with m/z 475.3783 and phase II metabolites were not found in our study whereas metabolites with m/z 505.3530, 523.3641, and 525.3788 were exclusively detected in our experiments. CONCLUSION: The metabolites identified using ultra-performance liquid chromatography coupled with triple quadrupole time-of-flight mass spectrometry in our study were mostly hydroxylated metabolites. This indicated that PPD was metabolized in human body mainly through phase I hepatic metabolism. The main metabolites are in 20,24-oxide form with multiple hydroxylation sites. Finally, the metabolic pathways of PPD in vivo (human) were proposed based on structural analysis.

8.
Mikrochim Acta ; 186(8): 590, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367778

RESUMO

A new sorbent was synthesized for restricted-access matrix solid phase extraction (RAM-SPE) of the diabetes drugs metformin (MET) and glimepiride (Glim). Mesoporous silica layers were placed on Fe3O4-magnetized graphene modified with sulfo-functionalized pore walls (denoted as magG@mSiO2-SO3H composites). The composites have a large specific surface (173 m2·g-1), appropriate pore sizes (typically 3.7 nm), and sulfo-functionalized pore walls. Magnetic separation can be accomplished within 10 s. The unique properties of the composites allow both MET and Glim to be selectively and quickly extracted from plasma sample. Following magnetic separation and elution by 50% aqueous acetonitrile with 4% ammonium solution, the two drugs were quantified by LC-MS/MS analysis. The assay has high selectivity, good linearity (2.5-4000 ng•mL-1 for MET and 0.02-1600 ng•mL-1 for Glim), a low detection limit (as low as 60 pg•mL-1 for MET and 1 pg•mL-1 for Glim), excellent recovery (above 92.2%), and good precision (RSDs <12%). The method was successfully applied in a pharmacokinetic study in beagle dogs. Graphical abstract Schematic representation of the synthesis of sulfo-functionalized magnetic graphene/mesoporous silica composites, giving a material of type magG@mSiO2-SO3H. Results showed its great potential as a feasible and alternative adsorbent for the selective extraction of MET and Glim from complicated biological samples.

9.
Front Chem ; 7: 248, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31058136

RESUMO

Objective: Chiral analysis is a crucial method to differentiate selegiline intake from drug abuse. A dried urine spot (DUS) analytical method based on spotting urine samples (10 µL) onto dried spot collection cards, and followed by air-drying and extraction, was developed and validated for the determination of selegiline, desmethylselegiline, R/S-methamphetamine, and R/S-amphetamine. Methods: Methanol (0.5 mL) was found to be the ideal extraction solvent for target extraction from DUSs under orbital-horizontal stirring on a lateral shaker at 1,450 rpm for 30 min. Determinations were performed by direct electrospray ionization tandem mass spectrometry (ESI-MS/MS) under positive electrospray ionization conditions using multiple reaction monitoring mode. The chromatographic system consisted of a ChirobioticTM V2 column (2.1 × 250 mm, 5 µm) and a mobile phase of methanol containing 0.1% (v/v) glacial acetic acid and 0.02% (v/v) ammonium hydroxide. Results and conclusions: The calibration curves were linear from 50 to 5,000 ng/mL, with r > 0.995 for all analytes, imprecisions ≤ 15% and accuracies between -11.4 and 11.7%. Extraction recoveries ranged from 48.6 to 105.4% with coefficients of variation (CV) ≤ 13.7%, and matrix effects ranged from 45.4 to 104.1% with CV ≤ 10.3%. The lower limit of quantification was 50 ng/mL for each analyte. The present method is simple, rapid (accomplished in 12 min), sensitive, and validated by a pharmacokinetic study in human urine collected after a single oral administration of SG.

10.
Talanta ; 195: 127-136, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30625522

RESUMO

In this study, a method for direct screening and identification of α-glucosidase inhibitors (AGIs) from extracts of natural products was established based on polyamidoamine (PAMAM) coated magnetic microspheres. A facile route to synthesize the magnetic PAMAM was employed and α-glucosidase was successfully covalently attached to its surface through cross linking of glutaraldehyde. Using the enzyme-loaded magnetic microspheres, potential inhibitors were fished out from crude extracts directly, followed by structure confirmation. The inhibitory activities of the screened components were further investigated by the enzyme-loaded magnetic microspheres. The Fe3O4 @PAMAM@α-Glu microspheres displayed favorable dispersibility, fast magnetic separation, large enzyme binding amount (42.9 µg•mg-1) and high enzyme activity. Moreover, the α-glucosidase on the surface of PAMAM coating maintained high storage stability and remarkable reusability. Taking advantage of specific interaction of the α-glucosidase with AGIs, the materials could selectively capture a known AGI (+)-catechin under the interference of an inactive compound salicylic acid, with a binding capacity as high as 15.4%. Additionally, using the Fe3O4 @PAMAM@α-Glu microspheres in the inhibition assay, the enzymatic reaction could be stopped by magnetic separation instead of the traditional addition of Na2CO3 solution, which not only eliminated the disturbance of termination reagent to the results, but also reused the immobilized α-glucosidase. The screening and inhibitory activity verification of potential ligands in Radix Paeoniae Rubra ("Chi-shao" in Chinese) extracts were achieved by using Fe3O4 @PAMAM@α-Glu microspheres, demonstrating practical applicability of our method. Therefore, the magnetic PAMAM-based screening approach could be a feasible and alternative strategy for discovering enzyme inhibitors from natural product extracts.


Assuntos
Enzimas Imobilizadas/química , Óxido Ferroso-Férrico/química , Inibidores de Glicosídeo Hidrolases/química , Paeonia , Extratos Vegetais/química , Poliaminas/química , alfa-Glucosidases/química , Fenômenos Magnéticos , Microesferas , Modelos Moleculares
11.
Drug Test Anal ; 11(6): 898-905, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30614204

RESUMO

BACKGROUND: Chiral analysis is a crucial way to differentiate selegiline (SG) intake from drug abuse. Oral fluid (OF) has been successfully used as an alternative matrix for blood testing in several pharmacokinetic studies. OBJECTIVE: The aim of this study is to describe the pharmacokinetics of SG and its main metabolites in OF after a single oral administration of SG which is meaningful for results interpretation in forensic analysis. METHODS: Ten milligrams of SG were orally administered to 8 volunteers, and OF samples were collected for up to 96 hours by having participants spit into polypropylene tubes without stimulation. These samples were submitted to liquid-liquid extraction before analysis by liquid chromatography-tandem mass spectrometry operating in positive ion multiple-reaction monitoring mode. RESULTS AND CONCLUSIONS: After oral administration, each analyte could be detected in OF specimens from all volunteers with an initial detection time of 0.50 hours. The Cmax values of SG, R-MA, R-AM and DM-SG were 50.93-992.67 ng/mL, 29.78-653.64 ng/mL, 8.22-150.15 ng/mL, and 4.34-16.25 ng/mL, respectively, at 0.5 hours, 1-11 hours, 1.5-11 hours, and 0.5-6 hours post dose. The times when the compounds were last determined in OF were 5-24 hours for SG, 52-96 hours for R-MA, 31-96 hours for R-AM, and 13-31 hours for DM-SG after oral administration. There is a period of time in OF in which only MA and AM are present without SG and DM-SG after a single dose of SG. The pharmacokinetic data could provide supplementary interpretation for OF tests in forensic science and drug treatment programs.


Assuntos
Anfetamina/farmacocinética , Anfetaminas/farmacocinética , Metanfetamina/farmacocinética , Inibidores da Monoaminoxidase/farmacocinética , Saliva/metabolismo , Selegilina/farmacocinética , Administração Oral , Anfetamina/metabolismo , Anfetaminas/metabolismo , Humanos , Extração Líquido-Líquido , Metanfetamina/metabolismo , Inibidores da Monoaminoxidase/administração & dosagem , Inibidores da Monoaminoxidase/metabolismo , Selegilina/administração & dosagem , Selegilina/metabolismo , Detecção do Abuso de Substâncias
12.
Chem Pharm Bull (Tokyo) ; 66(5): 527-534, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29503397

RESUMO

Uncaria rhynchophylla is woody climber plant distributed mainly in China and Japan, the stems and hooks of which can be collected as "Gou-Teng" for the treatment of hyperpyrexia, epilepsy and preeclampsia. Fudan University first manufactured KHR98, the extract of Uncaria rhynchophylla. In order to study the active components and structural information of KHR98, we established a HPLC coupled with quadrupole time-of-flight (Q-TOF)-MS method for rapid analysis of alkaloids. In qualitative analysis, a total of eight compounds, including four known alkaloids and four unknown components, were detected and identified. The fragmentation behaviors, such as the fragment ion information and the fragmentation pathways of the eight components were summarized simultaneously, and the concentration of the above components was determined by HPLC-MS method. The quantitative method was proved to be reproducible, precise and accurate. This study shed light on the standardization and quality control of the KHR98 and provided a foundation for the further research on pharmacology, follow-up clinical research and New Drug Applications.


Assuntos
Alcaloides/análise , Uncaria/química , Cromatografia Líquida de Alta Pressão , Conformação Molecular , Espectrometria de Massas em Tandem
13.
Biol Pharm Bull ; 40(7): 1021-1028, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28674245

RESUMO

A rapid, effective extraction technique has been established for measuring the gallic acid in rat plasma by using sandwich-structured graphene/mesoporous silica composites with C8-modified interior pore-walls as adsorbent. The unique characteristics of the graphene-silica composites excluded large molecules, like proteins, from the mesopore channels as a result of size exclusion effect, leading to a direct extraction of drug molecules from protein-rich biological samples such as plasma without any other pretreatment procedure. Followed by elution and centrifugation, the gallic acid-absorbed composites were rapidly isolated before LC-MS/MS. Serving as a reliable tool for analysis of Traditional Chinese Medicine: Changtai Granule, the newly developed method was fully validated and successfully applied in the pharmacokinetic study of gallic acid in rat plasma. Extraction recovery, matrix effect and stability were satisfactory in rat plasma. According to the results of pharmacokinetic studies, Changtai Granule exhibited greater adsorption, distribution and clearance properties of gallic acid in the treatment of ulcerative colitis. Hence, this study may offer a valuable alternative to simplify and speed up sample preparation, and be useful for clinical studies of related preparations.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Ácido Gálico/sangue , Grafite/química , Dióxido de Silício/química , Administração Oral , Animais , Ácido Gálico/farmacocinética , Limite de Detecção , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
14.
Anal Bioanal Chem ; 409(23): 5593-5602, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28730309

RESUMO

A new, simple, and fast infrared-assisted self enzymolysis extraction (IRASEE) approach for the extraction of total flavonoid aglycones (TFA) mainly including baicalein, wogonin, and oroxylin A from Scutellariae Radix is presented to enhance extraction yield. Extraction enzymolysis temperature, enzymolysis liquid-to-solid ratio, enzymolysis pH, enzymolysis time and infrared power, the factors affecting IRASEE procedure, were investigated in a newly designed, temperature-controlled infrared-assisted extraction (TC-IRAE) system to acquire the optimum analysis conditions. The results illustrated that IRASEE possessed great advantages in terms of efficiency and time compared with other conventional extraction techniques. Furthermore, the mechanism of IRASEE was preliminarily explored by observing the microscopic change of the samples surface structures, studying the main chemical compositions change of the samples before and after extraction and investigating the kinetics and thermodynamics at three temperature levels during the IRASEE process. These findings revealed that IRASEE can destroy the surface microstructures to accelerate the mass transfer and reduce the activation energy to intensify the chemical process. This integrative study presents a simple, rapid, efficient, and environmental IRASEE method for TFA extraction which has promising prospects for other similar herbal medicines. Graphical Abstract ᅟ.


Assuntos
Enzimas/metabolismo , Flavonoides/isolamento & purificação , Scutellaria/química , Raios Infravermelhos , Cinética , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
15.
J Sep Sci ; 40(10): 2278-2285, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28371337

RESUMO

In this paper, a facile extraction strategy is reported for the analysis of isopentenyl pyrophosphate, a key isoprenoid, based on magnetic core-shell microspheres with Ti4+ ion exterior walls coupled with liquid chromatography and tandem mass spectrometry. Because of their excellent hydrophilicity and biological compatibility, the polydopamine@Fe3 O4 -Ti4+ microspheres display ideal isopentenyl pyrophosphate extraction efficiency. The technique includes three steps: sample loading, nonphosphate washing, and phosphate elution. Moreover, the microspheres can be regenerated by thorough washing with a specific solvent and can be reused multiple times. The liquid chromatography with tandem mass spectrometry separation was performed on a Welch Ultimate® XB-C18 column with a total chromatographic analysis time of 5 min; the analytical recovery was 98.52%. The proposed method was used to determine the isopentenyl pyrophosphate concentration in rat plasma samples collected from the Shanghai Chest Hospital. The results indicate the prospective value of the as-made microspheres for the sensitive and selective enrichment of phosphate compounds in complicated matrices.


Assuntos
Hemiterpenos/sangue , Indóis , Microesferas , Compostos Organofosforados/sangue , Polímeros , Animais , Ratos
16.
Artigo em Inglês | MEDLINE | ID: mdl-28432922

RESUMO

In the present study, a novel sample preparation method based on magnetic core-mesoporous shell microspheres with C8-modified interior pore walls (C8-Fe3O4@mSiO2) was established for the identification of 20(S)-protopanaxadiol (PPD) metabolites in rat plasma by UPLC-Q-TOF-MS/MS analysis. C8-Fe3O4@mSiO2 allowed selective extraction of PPD metabolites from rat plasma by excluding macromolecules in the plasma owing to size exclusion effect. Five extraction conditions including the amount of C8-Fe3O4@mSiO2 microspheres used, extraction time, elution solvents, elution volume, and elution time were investigated and optimized. The present method was compared with two conventional sample preparation methods: protein precipitation and C8 solid phase extraction (C8-SPE). Our method provided higher UPLC intensity of result than protein precipitation method. While the resulting intensity of our method and that of C8-SPE were not significantly different, it consumed less processing time (15min 55s for C8-Fe3O4@mSiO2, and 27min 30s for C8-SPE). Finally, the proposed method was successfully applied in the identification of PPD metabolites in vivo, in which a total of 17 metabolites and the parent drug were identified in rat plasma.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Sapogeninas/sangue , Sapogeninas/metabolismo , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Óxido Ferroso-Férrico/química , Microesferas , Porosidade , Ratos , Dióxido de Silício/química
17.
Artigo em Inglês | MEDLINE | ID: mdl-27507666

RESUMO

A highly sensitive HPLC-MS/MS assay method was established to quantify 20(S)-protopanaxadiol (PPD) in human plasma with dexamethasone as an internal standard. The electrospray ion mass spectrometry (ESI-MS) was operated under the multiple reactions monitoring mode (MRM) using positive ion mode. PPD was extracted from 500µL plasma samples by liquid-liquid extraction then separated by a C18 analytical column with gradient elution. The concentration of PPD could be determined by this HPLC-MS/MS method over the range of 0.05-20ng/mL with the lower limit of quantification (LLOQ) of 0.05ng/mL. The method was successfully applied to phase IIa clinical trial of Yuxintine (PPD capsule) in which plasma samples of 87 subjects were analyzed following 6 weeks of oral administration of placebo or PPD capsules in 5 different doses. In this study, the measured concentration was linearly related to the oral dosage with R=0.9901. The minimum and maximum values of measured concentration were 0.06 and 11.60ng/mL, respectively. In addition, plasma concentrations of PPD in depression patients were reported for the first time in our study.


Assuntos
Antidepressivos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Sapogeninas/sangue , Espectrometria de Massas em Tandem/métodos , Antidepressivos/uso terapêutico , Humanos , Limite de Detecção , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Sapogeninas/uso terapêutico
18.
Anal Chim Acta ; 844: 35-43, 2014 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-25172813

RESUMO

We report herein an extraction method for the analysis of perfluorinated compounds in human serum based on magnetic core-mesoporous shell microspheres with decyl-perfluorinated interior pore-walls (Fe3O4@mSiO2-F17). Thanks to the unique properties of the Fe3O4@mSiO2-F17 microspheres, macromolecules like proteins could be easily excluded from the mesoporous channels due to size exclusion effect, and perfluorinated compounds (PFCs) in protein-rich biosamples such as serum could thus be directly extracted with the fluorocarbon modified on the channel wall without any other pretreatment procedure. The PFCs adsorbed Fe3O4@mSiO2-F17 microspheres could then be simply and rapidly isolated by using a magnet, followed by being identified and quantified by LC-MS/MS (high-performance liquid chromatography coupled to tandem mass spectrometry). Five perfluorinatedcarboxylic acids (C6, C8-C11) and perfluorooctane sulfonate (PFOS) were selected as model analytes. In order to achieve the best extraction efficiency, some important factors including the amount of Fe3O4@mSiO2-F17 microspheres added, adsorption time, type of elution solvent, eluting solvent volume and elution time were investigated. The ranges of the LOD were 0.02-0.05 ng mL(-1) for the six PFCs. The recovery of the optimized method varies from 83.13% to 92.42% for human serum samples.


Assuntos
Ácidos Alcanossulfônicos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Fluorocarbonos/química , Microesferas , Espectrometria de Massas em Tandem/métodos , Fluorocarbonos/sangue , Humanos , Magnetismo , Microscopia Eletrônica de Transmissão , Padrões de Referência , Espectroscopia de Infravermelho com Transformada de Fourier
19.
J Ethnopharmacol ; 151(3): 1124-1132, 2014 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-24389029

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Nephrotic syndrome (NS) is a clinical syndrome with a variety of causes, mainly characterized by heavy proteinuria. Podocyte injury plays a key role in proteinuria, one of the principal means for the control of NS is to prevent podocyte injury. Qi-Dan Fang consists of two of the most extensively applied herbal remedies among Traditional Chinese Medicine (TCM) (Radix Astragali Mongolici and Radix Salviae Miltiorrhizae, with a weight ratio of 5:1) which are specifically used for the treatment of various kidney diseases. In previous studies, we found that Qi-Dan Fang provides improvement to patients with adriamycin-induced nephrotic syndrome by alleviating proteinuria and serum lipid. The aim of this study is to study the efficiency of Qi-Dan Fang on NS model rat with renal dysfunction and podocyte injury, something which has not been carried out yet. MATERIALS AND METHODS: The rats were divided into Normal, Model, Jin Gui Shen Qi Pill (4.12 g/kg), Qi-Dan Fang (3.09, 6.17 and 12.34 g/kg/d) groups, they were each given a single tail intravenous injection of Adriamycin (6.0 mg/kg) except for the Normal group and were orally administered dosages of Qi-Dian Fang and Jin Gui Shen Qi pills once daily for 7 weeks. Following the treatment, the content of cystation C (CysC), blood urea nitrogen (BUN), serum creatinine (Scr) were measured with an autobiochemical analyser. The pathomorphological changes to the glomeruli, the mRNA expressions of nephrin, podocin, CD2AP genes and p53, bax, bcl-2 proteins expressions were also carried out to probe the effects of Qi-Dan Fang. RESULTS: (1) Qi-Dan Fang treatment raised the level of CysC in blood serum while lowering the content of BUN and Scr in the adriamycin-induced nephrotic syndrome rat model; (2) Long-term administration of Qi-Dan Fang was able to ameliorate pathomorphological change of glomeruli and repair the organization structure of Glomerulus; (3) Qi-Dan Fang could increase the mRNA expression of nephrin, podocin and CD2AP genes, down-regulate the expression of p53, bax proteins, while increased bcl-2 protein to protect the podocyte and restore Glomerular selective filtration function. CONCLUSIONS: Results of our present studies reveal that Qi-Dan Fang is able to enhance renal function, inhibit podocyte injury to provide improvements to the Adriamycin-induced nephrotic syndrome.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Síndrome Nefrótica/tratamento farmacológico , Substâncias Protetoras/uso terapêutico , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Antibióticos Antineoplásicos , Proteínas do Citoesqueleto/genética , Modelos Animais de Doenças , Doxorrubicina , Medicamentos de Ervas Chinesas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Rim/ultraestrutura , Masculino , Proteínas de Membrana/genética , Microscopia Eletrônica de Transmissão , Síndrome Nefrótica/induzido quimicamente , Síndrome Nefrótica/metabolismo , Síndrome Nefrótica/patologia , Fitoterapia , Podócitos/efeitos dos fármacos , Podócitos/metabolismo , Podócitos/patologia , Podócitos/ultraestrutura , Substâncias Protetoras/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
20.
Food Chem ; 150: 206-12, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24360441

RESUMO

A fast and effective extraction method has been developed for measuring the residue of cephalosporins (cefalexin, cefazolin, cefoperazone) in milk by using magnetic core-mesoporous shell microspheres with C18-functionalized interior pore-walls (C18-Fe3O4@mSiO2) as adsorbent. With no need for any protein precipitation procedure, the cephalosporins were directly adsorbed onto the C18-Fe3O4@mSiO2 microspheres through hydrophobic interaction with C18-groups (Octadecyl functional groups) functionalized in the interior walls of mesopore channels while the abundant proteins in milk sample were excluded out of the channel due to the size exclusion effect. Thereafter, the cephalosporins-absorbed C18-Fe3O4@mSiO2 microspheres were rapidly isolated by placing a magnet, and followed by liquid chromatography-tandem mass spectrometry analysis after eluted by methanol. Various parameters which could affect the extraction performance were optimised. The newly developed extraction method was successfully applied in determination of cephalosporin residues in milk samples, offering a valuable alternative to simplify and speed up the sample preparation step.


Assuntos
Antibacterianos/isolamento & purificação , Cefalosporinas/isolamento & purificação , Leite/química , Resíduos de Praguicidas/isolamento & purificação , Extração em Fase Sólida/métodos , Adsorção , Animais , Antibacterianos/química , Cefalosporinas/química , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Imãs/química , Microesferas , Resíduos de Praguicidas/química , Porosidade , Extração em Fase Sólida/instrumentação , Espectrometria de Massas em Tandem/métodos
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