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1.
Anal Bioanal Chem ; 416(4): 945-957, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38051414

RESUMEN

Histamine causes allergic reactions and can serve as an indicator for assessing food quality. This study designed and developed a dispersive micro solid-phase extraction (D-µSPE) method that combined the advantages of dispersive liquid-liquid extraction and solid-phase extraction (SPE). Molecularly imprinted polymers (MIPs) were employed as the solid phase in the D-µSPE method to extract histamine in wine samples. We used microwave energy to significantly reduce the synthesis time, achieving an 11.1-fold shorter synthesis time compared to the conventional MIP synthetic method. Under optimized D-µSPE conditions, our results showed that the dispersive solvent could effectively increase the adsorption performance of MIPs in wine samples by 97.7%. To improve the sensitivity of histamine detection in gas chromatography-mass spectrometry, we employed the microwave-assisted tandem derivatization method to reuse excess derivatization reagents and reduce energy consumption and reaction time. Calibration curves were constructed for wine samples spiked with 0-400 nmol histamine using the standard addition method, resulting in good linearity with a coefficient of determination of 0.999. The intra- and inter-batch relative standard deviations of the slope and intercept were < 0.7% and < 5.3%, respectively. The limits of quantitation and detection were 0.4 nmol and 0.1 nmol, respectively. The developed method was successfully applied to analyze the histamine concentration in 10 commercial wine samples. In addition, the AGREEprep tool was used to evaluate the greenness performance of the developed method, which obtained a higher score than the other reported methods.


Asunto(s)
Impresión Molecular , Vino , Vino/análisis , Cromatografía Líquida de Alta Presión/métodos , Histamina/análisis , Polímeros/química , Extracción en Fase Sólida/métodos , Impresión Molecular/métodos
2.
Anal Methods ; 15(36): 4710-4717, 2023 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-37680175

RESUMEN

Alzheimer's disease is a progressive neurodegenerative condition that causes brain cell death and is the leading cause of dementia. Most patients with Alzheimer's disease are diagnosed with late-onset Alzheimer's disease (LOAD), with apolipoprotein E (APOE) genotypes being highly associated with the frequency of LOAD risk. A fluorescence detection system coupled with oligonucleotide ligation and magnetic separation was developed to identify two single-nucleotide polymorphisms (SNPs) for the APOE gene and recognize APOE alleles for LOAD. The system utilized a fluorescence probe with one base-discriminating nucleoside for SNP (F probe) and a perfectly complementary biotin-modified sequence against the target DNA (P probe). When the F and P probes matched the target DNA sequences, DNA ligation occurred, and ligation products were produced. Streptavidin magnetic beads were subsequently employed to remove the ligation products, and a decrease in fluorescence intensity was observed in the supernatant compared to when there was no target DNA. This system detected two SNPs of APOE alleles, namely rs429358 and rs7412. The results indicated that the R-values ((F0 - F1)/F0) for rs429358 were 0.92 ± 0.002 for the T/T target, 0.47 ± 0.004 for the T/C target and 0.11 ± 0.004 for the C/C target, respectively. The R-values for rs7412 were 0.73 ± 0.009 for the C/C target, 0.42 ± 0.001 for the C/T target and 0.16 ± 0.007 for the T/T target, respectively. F0 and F1 represent the fluorescence intensity of the F probe without and with target DNA, respectively. Based on fluorescence intensity, the fluorescence detection system was able to identify the genotypes of the APOE gene accurately to evaluate the risk of Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/diagnóstico , Oligonucleótidos/genética , Fluorescencia , Apolipoproteínas E/genética , Polimorfismo de Nucleótido Simple/genética , ADN/genética
3.
Chem Biol Interact ; 380: 110538, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37164279

RESUMEN

The enzyme pyruvate kinase M2 (PKM2) is involved in glycolysis, which plays an important role in the regulation of tumor progression. In this study, we investigated the anti-tumor activity of N-(4-(3-(3-(methylamino)-3-oxopropyl)-5-(4'-(trifluoromethyl)-[1,1'-biphenyl]-4-yl)-1H-pyrazol-1-yl)phenyl)propiolamide (MTP), a PKM2 inhibitor, in oral squamous cell carcinoma (OSCC) cells. Our results showed that MTP inhibited cell growth with IC50 values of 0.59 µM and 0.78 µM in SCC2095 and HSC-3 OSCC cells, respectively. MTP induced caspase-dependent apoptosis, which was associated with the modulation of PKM2 and oncogenic biomarkers epidermal growth factor receptor and ß-catenin. In addition, MTP increased the generation of reactive oxygen species (ROS) and modulated the expression of autophagic gene products, including LC3B-II and p62. Western blotting showed that MTP inhibited Janus kinase 2 (JAK2) signaling, and JAK2 overexpression partially reversed MTP-mediated cytotoxicity. Taken together, these data indicate the potential use of MTP as a therapeutic agent for OSCC.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello , Janus Quinasa 2/metabolismo , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/metabolismo , Línea Celular Tumoral , Apoptosis , Autofagia , Proliferación Celular
4.
Anal Methods ; 14(37): 3694-3701, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-36102878

RESUMEN

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is a rapid and low-solvent-consumption technique. However, almost every mass in the low mass-to-charge-ratio region of the mass spectrum appears as strongly fluctuating matrix background signals. Thus, it is difficult to identify small molecules using this technique. In this study, we used methanol to methylate valsartan, an angiotensin II receptor blocker that is commonly used to treat high blood pressure and heart failure. The methylation derivatization of valsartan enhanced the detection sensitivity and transformed the detection m/z ratio. The liquid-phase microextraction of valsartan in human plasma (20 µL) was achieved by acidifying valsartan with HCl aqueous solution and extracting it with toluene. An acetyl chloride/anhydrous methanol mixture was added for methylation derivatization, which was completed within 30 min at 30 °C. Finally, the residue was re-dissolved in irbesartan methanolic solution, which together with the matrix 2-mercaptobenzothiazole was spotted on an AnchorChip target plate for MALDI-TOF MS analysis. Liquid-phase microextraction was performed and the methylation-derivatization parameters were investigated. The valsartan calibration range was 0.2-10 µg mL-1 with good linearity in human plasma. In the within- and between-run analyses, the relative standard deviation and relative error were both <11.32%. This method was successfully applied to determine the valsartan concentration in the plasma of 10 patients with hypertension.


Asunto(s)
Metanol , Tolueno , Antagonistas de Receptores de Angiotensina , Humanos , Indicadores y Reactivos , Irbesartán , Metilación , Solventes , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Valsartán
5.
J Chromatogr A ; 1659: 462629, 2021 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-34700182

RESUMEN

Biogenic amines are quality control criteria for foods that are potentially toxic to humans. In this study, amidation derivatization for biogenic amines and liquid-solid phase transition microextraction were carried out simultaneously for food sample pretreatment. The derivatization reaction was executed in one pot with coumarin-3-carboxylic acid as the derivatizing reagent and (1-cyano-2-ethoxy-2-oxoethylidenaminooxy)dimethylamino-morpholino-carbenium hexafluorophosphate as the coupling agent. Liquid-solid phase transition microextraction was achieved by the salting-out effect, using a phase change salt (1 M disodium hydrogen phosphate) solution. The combined derivatization and microextraction process was completed within 3 min at 30 °C, and the liquid top phase was easily obtained by placing the tube in an ice bath. Finally, a narrowbore liquid chromatograph coupled with a UV detector was used to determine the levels of six biogenic amines. The coupling agent-assisted derivatization and liquid-solid phase transition microextraction parameters were also investigated. The quantitative linear ranges were 3-400 µM for histamine, putrescine, spermidine, cadaverine, and tyramine and 5-400 µM for spermine, and the detection limit was 1 µM. The relative standard deviations of the intra- and inter-batches were <5.3% and 8.4%, respectively, while the relative error was <4.5% for both. We successfully applied this simultaneous derivatization-microextraction method to determine the biogenic amines in fermented foods.


Asunto(s)
Aminas Biogénicas , Microextracción en Fase Líquida , Aminas Biogénicas/análisis , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Histamina , Humanos , Microextracción en Fase Sólida
6.
Mar Drugs ; 19(5)2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33925873

RESUMEN

In this study, the anti-proliferative effect of ilimaquinone, a sesquiterpene derivative from the marine sponge, in breast cancer cells was investigated. Ilimaquinone inhibited the proliferation of MCF-7 and MDA-MB-231 breast cancer cells with IC50 values of 10.6 µM and 13.5 µM, respectively. Non-tumorigenic human breast epithelial cells were less sensitive to ilimaquinone than breast cancer cells. Flow cytometric and Western blot analysis showed that ilimaquinone induced S-phase arrest by modulating the expression of p-CDC-2 and p21. Ilimaquinone induces apoptosis, which is accompanied by multiple biological biomarkers, including the downregulation of Akt, ERK, and Bax, upregulation of p38, loss of mitochondrial membrane potential, increased reactive oxygen species generation, and induced autophagy. Collectively, these findings suggest that ilimaquinone causes cell cycle arrest as well as induces apoptosis and autophagy in breast cancer cells.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Poríferos/metabolismo , Quinonas/farmacología , Sesquiterpenos/farmacología , Animales , Antineoplásicos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Femenino , Humanos , Células MCF-7 , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Quinonas/aislamiento & purificación , Especies Reactivas de Oxígeno/metabolismo , Puntos de Control de la Fase S del Ciclo Celular/efectos de los fármacos , Sesquiterpenos/aislamiento & purificación , Transducción de Señal
7.
Environ Toxicol ; 36(7): 1316-1325, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33713530

RESUMEN

Secondary metabolites in marine organisms exhibit various pharmacological activities against diseases, such as cancer. In this study, the anti-proliferative effect of JBIR-100, a macrolide isolated from Streptomyces sp., was investigated in breast cancer cells. Cell growth was inhibited in response to JBIR-100 treatment concentration- and time-dependently in both MCF-7 and MDA-MB-231 breast cancer cells. JBIR-100 caused apoptosis, as verified by caspase activation and the cleavage of PARP. Western blotting revealed that JBIR-100 modulated the expression of Akt/NF-κB signaling components and Bcl-2 family members. Overexpression of Mcl-1 partially rescued MCF-7 cells from JBIR-100-induced cytotoxicity. In addition, transmission electron microscopy analyses, confocal analysis, and western blot assay indicated that JBIR-100 inhibited autophagy in MCF-7 cells. Exposure to the autophagy inhibitor did not synergize JBIR-100-induced apoptosis. In summary, our results suggested that JBIR-100 may be potentially used for breast cancer therapy.


Asunto(s)
Neoplasias de la Mama , Streptomyces , Apoptosis , Autofagia , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Humanos , Células MCF-7 , Macrólidos/farmacología
8.
Molecules ; 25(20)2020 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-33053784

RESUMEN

This study explores the amounts of common chemical ultraviolet (UV) filters (i.e., avobenzone, bemotrizinol, ethylhexyl triazone, octocrylene, and octyl methoxycinnamate) in cosmetics and the human stratum corneum. An ultrasound-vortex-assisted dispersive liquid-liquid microextraction (US-VA-DLLME) method with a high-performance liquid chromatography-diode array detector was used to analyze UV filters. A bio-derived solvent (i.e., anisole) was used as the extractant in the US-VA-DLLME procedure, along with methanol as the dispersant, a vortexing time of 4 min, and ultrasonication for 3 min. The mass-transfer rate of the extraction process was enhanced due to vortex-ultrasound combination. Various C18 end-capped columns were used to investigate the separation characteristics of the UV filters, with XBridge BEH or CORTECS selected as the separation column. Calibration curves were constructed in the 0.05-5 µg/mL (all filters except octocrylene) and 0.1-10 µg/mL (octocrylene) ranges, and excellent analytical linearities with coefficients of determination (r2) above 0.998. The developed method was successfully used to analyze sunscreen. Moreover, experiments were designed to simulate the sunscreen-usage habits of consumers, and the cup method was used to extract UV filters from the human stratum corneum. The results suggest that a makeup remover should be employed to remove water-in-oil sunscreens from skin.


Asunto(s)
Cosméticos , Epidermis/química , Microextracción en Fase Líquida/métodos , Ondas Ultrasónicas , Cromatografía Líquida de Alta Presión , Humanos , Solventes
9.
Int J Mol Sci ; 21(21)2020 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-33114727

RESUMEN

We recently isolated a cardiac glycoside (CG), αldiginoside, from an indigenous plant in Taiwan, which exhibits potent tumor-suppressive efficacy in oral squamous cell carcinoma (OSCC) cell lines (SCC2095 and SCC4, IC50 < 0.2 µM; 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays). Here, we report that αldiginoside caused Sphase arrest and apoptosis, through the inhibition of a series of signaling pathways, including those mediated by cyclin E, phospho-CDC25C (p-CDC25C), and janus kinase/signal transducer and activator of transcription (JAK/STAT)3. αldiginoside induced apoptosis, as indicated by caspase activation and poly (ADP-ribose) polymerase (PARP) cleavage. Equally important, αldiginoside reduced Mcl-1 expression through protein degradation, and overexpression of Mcl-1 partially protected SCC2095 cells from αldiginoside's cytotoxicity. Taken together, these data suggest the translational potential of αldiginoside to foster new therapeutic strategies for OSCC treatment.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Carcinoma de Células Escamosas/metabolismo , Glicósidos Cardíacos/farmacología , Neoplasias de la Boca/metabolismo , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/genética , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/genética , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/genética , Proteolisis , Transducción de Señal/efectos de los fármacos
10.
PLoS One ; 15(7): e0235607, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32614909

RESUMEN

Global climate change has led to a significant increase in temperature over the last century and has been associated with significant increases in the severity and frequency of heat injury (HI). The consequences of HI included dehydration and rhabdomyolysis, leading to acute kidney injury, which is now recognized as a clear risk factor for chronic kidney disease (CKD). We aimed to investigate the effects of HI on the risk of CKD. This nationwide longitudinal population-based retrospective cohort study utilized the Taiwan National Health Insurance Research Database (NHIRD) data. We enrolled patients with HI who were followed in NHIRD system between 2000 and 2013.We excluded patients diagnosed with CKD or genital-urinary system-related disease before the date of the new HI diagnosis. The control cohort consisted of individuals without HI history. The patients and control cohort were selected by 1:4 matching according to the following baseline variables: sex, age, index year, and comorbidities. The outcome measure was CKD diagnosis. In total, 815 patients diagnosed with HI were identified. During the 13 year observation period, we identified 72 CKD events (8.83%) in the heat stroke group and 143 (4.38%) CKD events in the control group. Patients with heat stroke had an increased risk of CKD than the control patients (adjusted HR = 4.346, P < 0.001) during the follow-up period. The risk of end-stage renal disease was also significantly increased in the heat stroke group than in the control group (adjusted hazards ratio: 9.078, p < 0.001). HI-related CKD may represent one of the first epidemics due to global warming. When compared to those without HI, patients with HI have an increased CKD risk.


Asunto(s)
Golpe de Calor/patología , Insuficiencia Renal Crónica/diagnóstico , Adulto , Bases de Datos Factuales , Femenino , Golpe de Calor/complicaciones , Calor , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/patología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/patología , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Adulto Joven
11.
Environ Toxicol ; 34(9): 983-991, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31062913

RESUMEN

Oral squamous cell carcinoma (OSCC) is the fifth common cause of cancer mortality in Taiwan with high incidence and recurrence and needs new therapeutic strategies. In this study, ursolic acid (UA), a triterpenoid, was examined the antitumor potency in OSCC cells. Our results showed that UA inhibited the proliferation of OSCC cells in a dose- and time-dependent manner in both Ca922 and SCC2095 oral cancer cells. UA induced caspase-dependent apoptosis accompanied with the modulation of various biological biomarkers including downregulating Akt/mTOR/NF-κB signaling, ERK, and p38. In addition, UA inhibited angiogenesis as evidenced by abrogation of migration/invasion and blocking MMP-2 secretion in Ca922 cells. Interestingly, UA induced autophagy in OSCC cells, as manifested by LC3B-II conversion and increased p62 expression and accumulation of autophagosomes. Inhibition by autophagy inhibitor enhanced UA-mediated apoptosis in Ca922 cells. The experiment provides a rationale for using triterpenoid in the treatment of OSCC.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Carcinoma de Células Escamosas/patología , Neoplasias de la Boca/patología , Triterpenos/farmacología , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo , Humanos , Neoplasias de la Boca/metabolismo , FN-kappa B/metabolismo , Transducción de Señal , Ácido Ursólico
12.
Talanta ; 199: 464-471, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30952285

RESUMEN

In this study, an ecofriendly analytical method was developed for determining glutathione (GSH) levels in biomatrix samples. 9-(bromomethyl)acridine was used for the first time as a derivatization reagent in GSH analysis. Microwave-assisted derivatization reduced the reaction time to 1 min. After derivatization, coacervative extraction was employed to extract GSH derivative from the complex biomatrix and to increase sensitivity. Because the negatively charged group of the GSH derivative was neutralized by the extracting agent Aliquat 336, aggregates formed without any coacervating agents. Furthermore, capillary liquid chromatography coupled with ultraviolet detection was applied to decrease waste generation and increase selectivity. This method successfully quantified GSH levels in various biomatrices, including erythrocytes, HaCaT cells, BALB/3T3 cells, and 3T3-L1 fibroblasts. This method only required a low sample volume (≤10 µL). A standard addition method was utilized to spike the biomatrix samples with 0-4.8 nmol GSH to construct calibration curves. The proposed method performed well, with a determination coefficient of 0.999 and relative standard deviations of less than 6.59% for the slope and the intercept, as determined by linear regression analysis. The limit of detection of GSH in the standard solution was 800 nM or 0.4 pmol. Compared to non-derivatized GSH, the proposed method for detecting derivatized GSH provides 750-fold greater sensitivity.

13.
Mar Drugs ; 16(7)2018 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-30018246

RESUMEN

The peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor that plays a key role in regulating cellular metabolism, and is a therapeutic target for cancer therapy. To search for potential PPARγ activators, a compound library comprising 11 marine compounds was examined. Among them, a sterol, 3ß,11-dihydroxy-9,11-secogorgost-5-en-9-one (compound 1), showed the highest PPARγ activity with an IC50 value of 8.3 µM for inhibiting human breast adenocarcinoma cell (MCF-7) growth. Western blotting experiments showed that compound 1 induces caspase activation and PARP cleavage. In addition, compound 1 modulated the expression of various PPARγ-regulated downstream biomarkers including cyclin D1, cyclin-dependent kinase (CDK)6, B-cell lymphoma 2 (Bcl-2), p38, and extracellular-signal-regulated kinase (ERK). Moreover, compound 1 increased reactive oxygen species (ROS) generation, upregulated the phosphorylation and expression of H2AX, and induced autophagy. Interestingly, pre-treatment with the autophagy inhibitor 3-methyladenine rescued cells from compound 1-induced growth inhibition, which indicates that the cytotoxic effect of compound 1 is, in part, attributable to its ability to induce autophagy. In conclusion, these findings suggest the translational potential of compound 1 in breast cancer therapy.


Asunto(s)
Antozoos/metabolismo , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Esteroles/farmacología , Animales , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ciclina D1/metabolismo , Quinasa 6 Dependiente de la Ciclina/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Humanos , Células MCF-7 , PPAR gamma/metabolismo , Fosforilación/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
14.
J Chromatogr A ; 1550: 68-74, 2018 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-29609861

RESUMEN

A simple cyclodextrin-mediated capillary zone electrophoresis method equipped with a laser-induced fluorescence detector was developed for chiral analysis of the excitatory amino acids aspartate (Asp) and glutamate (Glu). Plasma and cerebrospinal fluid (CSF) samples were pretreated with centrifugal filter devices before analysis to remove high-molecular-weight proteins (molecular weight cut-off: 3000) and then derivatized using 10 mM 6-carboxyfluorescein N-hydroxysuccinimide ester in DMSO under sonication at 25 °C for 2 h. After the derivatization reaction, reacted samples were diluted 100-fold with 5-([4,6-dichlorotriazin-2-yl]amino)fluorescein hydrochloride (DTAF) solution and then hydrodynamically subjected to capillary electrophoresis (0.5 psi for 5 s, injection volume 8.27 nL). The separation buffer consisted of 50 mM borate buffer (pH 9.0) with 6 mM γ-CD and 0.1% polyvinylpyrrolidone, and the separation voltage was set at 20 kV. In the linearity calculations for the determination of d/l-Asp and d/l-Glu in plasma and CSF, a standard addition method was utilized to spike solutions with 0-20.0 µg mL-1l-Glu and 0-2.0 µg mL-1d-Glu and d/l-Asp to construct calibration curves. Correlation coefficients were above 0.998 for every analyte. The limits of detection (S/N = 3) for d/l-Asp and d/l-Glu standard solutions were 0.85-0.96 µg mL-1. The proposed method was applied successfully to determine d/l-Asp and d/l-Glu concentrations in the plasma and CSF samples of 26 patients with Alzheimer's disease (AD), and the association between these concentrations and disease severity was investigated. Statistical analysis showed a moderately negative correlation (r = -0.158) between plasma l-Asp concentration and AD severity.


Asunto(s)
Enfermedad de Alzheimer/patología , Ácido Aspártico/análisis , Ácido Aspártico/química , Progresión de la Enfermedad , Electroforesis Capilar/métodos , Ácido Glutámico/análisis , Ácido Glutámico/química , Ultrasonido/métodos , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/líquido cefalorraquídeo , Boratos/química , Tampones (Química) , Fluoresceínas/química , Humanos , Concentración de Iones de Hidrógeno , Reproducibilidad de los Resultados , Estereoisomerismo , Succinimidas/química
15.
Food Chem ; 241: 411-418, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28958548

RESUMEN

Parabens are common preservatives and environmental hormones. As such, possible detrimental health effects could be amplified through their widespread use in foods, cosmetics, and pharmaceutical products. Thus, the determination of parabens in such products is of particular importance. This study explored vortex-assisted dispersive liquid-liquid microextraction techniques based on the solidification of a floating organic drop (VA-DLLME-SFO) and salt-assisted cloud point extraction (SA-CPE) for paraben extraction. Microanalysis was performed using a capillary liquid chromatography-ultraviolet detection system. These techniques were modified successfully to determine four parabens in 19 commercial products. The regression equations of these parabens exhibited good linearity (r2=0.998, 0.1-10µg/mL), good precision (RSD<5%) and accuracy (RE<5%), reduced reagent consumption and reaction times (<6min), and excellent sample versatility. VA-DLLME-SFO was also particularly convenient due to the use of a solidified extract. Thus, the VA-DLLME-SFO technique was better suited to the extraction of parabens from complex matrices.


Asunto(s)
Parabenos/análisis , Cromatografía Líquida de Alta Presión , Cosméticos , Microextracción en Fase Líquida , Conservadores Farmacéuticos
16.
J Chromatogr A ; 1524: 29-36, 2017 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-28989034

RESUMEN

Detection of polar organic compounds (POCs) using gas chromatography (GC) is not straightforward due to high polarity, hydrophilicity, and low volatility of POCs. In this study, we report a tandem microwave-assisted derivatization method combined with salting-out assisted liquid-liquid microextraction (SALLME) to modify successively the polar groups of POCs in protic and aprotic solvents. Biothiols (cysteine and homocysteine) served as a proof of concept for this method because they possess three polar groups (thiol, amine, and carboxyl); the derivatizing reagent was 3,4,5-trifluorobenzyl bromide (Br-TFB) for alkylation. The solubility of the POCs in the protic or aprotic reaction medium affected the number of TFB molecules attached. Using the tandem derivatization with Br-TFB, the thiol and amine groups of biothiols were alkylated in the protic system, and the carboxylic groups of biothiols were alkylated in the aprotic system. The developed method was then successfully applied to measure biothiols in human urine. Because of the complex urine matrix and the lack of urine samples without endogenous biothiols, the standard addition method was utilized to avoid the matrix effect, check the recovery, and calculate the initial biothiol content in the urine. Regarding the linearity of the standard addition curves, the coefficient of determination was >0.996, and the linear regression showed satisfactory reproducibility with a relative standard deviation <3.9% for the slope and <8.8% for the intercept. The levels of cysteine and homocysteine in healthy human urine ranged from 28.8 to 111µmolL-1 and from 1.28 to 3.73µmolL-1, respectively. The proposed method effectively increased the sensitivity of GC-MS assays of water-soluble compounds in human urine.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Microextracción en Fase Líquida , Compuestos de Sulfhidrilo/orina , Urinálisis/métodos , Cisteína/orina , Humanos , Límite de Detección , Modelos Lineales , Microextracción en Fase Líquida/instrumentación , Microondas , Reproducibilidad de los Resultados , Solventes
17.
Molecules ; 22(3)2017 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-28294989

RESUMEN

Myoporum bontioides is a traditional medicinal plant in Asia with various biological activities, including anti-inflammatory and anti-bacterial characteristics. To identify the bioactive constituents from M. bontioides, a newly-identified flavone, 3,4'-dimethoxy-3',5,7-trihydroxyflavone (compound 1), along with eight known compounds, were investigated in human MCF-7 breast cancer, SCC4 oral cancer, and THP-1 monocytic leukemia cells. Among these compounds, compound 1 exhibited the strongest antiproliferative activity with half-maximal inhibitory concentration (IC50) values ranging from 3.3 µM (MCF-7) to 8.6 µM (SCC4). Flow cytometric analysis indicated that compound 1 induced G2/M cell cycle arrest in MCF-7 cells. Mechanistic evidence suggests that the G2/M arrest could be attributable to compound 1's modulatory effects on the phosphorylation and expression of numerous key signaling effectors, including cell division cycle 2 (CDC2), CDC25C, and p53. Notably, compound 1 downregulated the expression of histone deacetylase 2 (HDAC2) and HDAC4, leading to increased histone H3 acetylation and p21 upregulation. Together, these findings suggest the translational potential of compound 1 as a breast cancer treatment.


Asunto(s)
Neoplasias de la Mama/metabolismo , Flavonas/farmacología , Puntos de Control de la Fase M del Ciclo Celular , Myoporum/química , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Flavonas/química , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Células MCF-7 , Extractos Vegetales/química , Extractos Vegetales/farmacología , Transducción de Señal/efectos de los fármacos
18.
Sci Rep ; 7: 39907, 2017 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-28057923

RESUMEN

4-Hydroxybenzoate is a phenolic derivative of alkyl benzoates and is a widely used preservative in cosmetic and pharmaceutical products. The presence of 4-hydroxybenzoates in the human body may result from the use of pharmaceutical and personal care products. These compounds are also known to exhibit estrogenic and genotoxic activities. The potential adverse effects of these compounds include endocrine disruption, oxidative and DNA damage, contact dermatitis, and allergic reactions. This study used two mass spectrometry methods that are applicable when using a derivatization-enhanced detection strategy (DEDS) to screen 4-hydroxybenzoates and their metabolites. Chemical derivatization was used to enhance the detection of these compounds. To evaluate the metabolic process triggered by UV radiation, human keratinocyte HaCaT cells treated with these 4-hydroxybenzoates were further exposed to UVA, UVB and UVC radiation. Metabolites transformed by human keratinocytes in the chemical derivatization procedure were identified by a nano ultra-performance liquid chromatographic system (nanoUPLC) coupled with LTQ Orbitrap. The experiments confirmed the feasibility of this method for identifying 4-hydroxybenzoate metabolites and for high-throughput screening of 4-hydroxybenzoate in commercial products (50 samples) by the DEDS.


Asunto(s)
Cromatografía Liquida/métodos , Cosméticos/análisis , Queratinocitos/química , Espectrometría de Masas/métodos , Parabenos/análisis , Células Cultivadas , Cosméticos/efectos adversos , Femenino , Humanos , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Queratinocitos/efectos de la radiación , Masculino , Parabenos/efectos adversos , Rayos Ultravioleta/efectos adversos , Adulto Joven
19.
J Chromatogr A ; 1464: 32-41, 2016 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-27562416

RESUMEN

A novel aqueous solvent-based dispersive liquid-liquid microextraction (AS-DLLME) method was combined with narrow-bore liquid chromatography and fluorescence detection for the determination of hydrophilic compounds. A remover (non-polar solvent) and extractant (aqueous solution) were introduced into the derivatization system (acetonitrile) to obtain a water-in-oil emulsion state that increased the mass transfer of analytes. As a proof of concept, three quaternary ammonium substances, including butyrobetaine, l-carnitine and acetyl-l-carnitine, were also used as analytes and determined in pharmaceuticals, personal care products, food and human plasma. The analytes were derivatized with 4-bromomethylbiphenyl for fluorescence detection and improved retention in the column. The linear response was 10-2000nM for l-carnitine and acetyl-l-carnitine with a good determination coefficient (r(2)>0.998) in the standard solution. The detection limit for l-carnitine and acetyl-l-carnitine was 4.5 fmol. The method was also successfully applied to a 1µL sample of human plasma. In the linearity calculations for determining butyrobetaine, l-carnitine and acetyl-l-carnitine in human plasma, the determination coefficients ranged from 0.996 to 0.999. Linear regression exhibited good reproducibility and a relative standard deviation better than 7.50% for the slope and 9.06% for the intercept. To characterize highly hydrophilic compounds in various samples, the proposed method provides good sensitivity for a small sample volume with a low consumption of toxic solvents.


Asunto(s)
Betaína/análogos & derivados , Carnitina/sangre , Carnitina/aislamiento & purificación , Microextracción en Fase Líquida/métodos , Betaína/sangre , Betaína/química , Betaína/aislamiento & purificación , Carnitina/química , Cromatografía Liquida/métodos , Fluorescencia , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Límite de Detección , Microextracción en Fase Líquida/instrumentación , Reproducibilidad de los Resultados
20.
J Chromatogr A ; 1410: 60-7, 2015 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-26253833

RESUMEN

A novel, simple and quick sample preparation method was developed and used for pre-concentration and extraction of six phenylpropenes, including anethole, estragole, eugenol, methyl eugenol, safrole and myristicin, from oil samples by dual dispersive liquid-liquid microextraction. Gas chromatography-mass spectrometry was used for determination and separation of compounds. Several experimental parameters affecting extraction efficiency were evaluated and optimized, including forward-extractant type and volume, surfactant type and concentration, water volume, and back-extractant type and volume. For all analytes (10-1000ng/mL), the limits of detection (S/N≧3) ranged from 1.0 to 3.0ng/mL; the limits of quantification (S/N≧10) ranged from 2.5 to 10.0ng/mL; and enrichment factors ranged from 3.2 to 37.1 times. Within-run and between-run relative standard deviations (n=6) were less than 2.61% and less than 4.33%, respectively. Linearity was excellent with determination coefficients (r(2)) above 0.9977. The experiments showed that the proposed method is a simple, effective, and environmentally friendly method of analyzing phenylpropenes in oil samples.


Asunto(s)
Alquenos/análisis , Derivados del Benceno/análisis , Aceites de Plantas/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Microextracción en Fase Líquida/métodos , Agua
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