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1.
J Pharm Biomed Anal ; 171: 22-29, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30959316

RESUMO

A green and efficient microemulsion liquid chromatographic (MELC) method using fatty acid as co-surfactant and electrochemical detection was established and validated for the determination of four caffeoylquinic acid isomers and caffeic acid in honeysuckle samples. The influences of each individual component within the isocratic oil-in-water (O/W) microemulsion mobile phase were systematically investigated, such as the type and concentration of co-surfactant, concentration of sodium dodecyl sulphate (SDS), organic modifier addition, type and concentration of oil phase, pH and detection voltage. Results indicated that excellent resolution was achieved using 3.0% w/v of propionic acid, 0.5% w/v of ethyl acetate, 1.0% w/v of SDS, 5% w/v acetonitrile, 90.5% v/v of water and 25 mM sodium dihydrogen phosphate at pH = 3 as microemulsion mobile phase and 0.8 V as the optimal voltage value. Under the optimal condition, analytical performance of developed method was evaluated. The detection limits were below 17.3 ng/mL and intra-day and inter-day precisions by relative standard deviations (RSD%) were between 0.5% and 3.6%. Satisfactory recovery (in the range of 83.8-109.1%) with good repeatability lower than 4.7% (n = 3) was obtained. Therefore, the developed O/W MELC method was rapid, precise and accurate for simultaneous determination of neochlorogenic acid, chlorogenic acid, isochlorogenic acid A and isochlorogenic acid C in honeysuckle samples, with contents of 2.6, 28.7, 18.1 and 5.2 mg/g, respectively.

2.
Acta Pharmacol Sin ; 39(11): 1787-1796, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30181579

RESUMO

Mammalian hepatitis B X-interacting protein (HBXIP) is an 18-kDa protein that regulates a large number of transcription factors such as TF-IID, E2F1, SP1, STAT3, c-Myc, and LXR by serving as an oncogenic transcription coactivator and plays an important role in the development of breast cancer. We previously showed that HBXIP as an oncoprotein could enhance the promoter activity of MDM2 through coactivating p53, promoting the MDM2 transcription in breast cancer. In this study we investigated the molecular mechanisms underlying the modulation of MDM2/p53 interaction by HBXIP in human breast cancer MCF-7 cells in vitro and in vivo. We showed that HBXIP could up-regulate MDM2 through inducing DNA methylation of miR-18b, thus suppressing the miR-18b expression, leading to the attenuation of p53 in breast cancer cells. In addition, HBXIP could promote the phosphorylation of MDM2 by increasing the level of pAKT and bind to pMDM2, subsequently enhancing the interaction between MDM2 and p53 for the down-regulation of p53 in breast cancer cells. In MCF-7 breast cancer xenograft nude mice, we also observed that overexpression of HBXIP promoted breast cancer growth through the miR-18b/MDM2 and pAKT/MDM2 pathways. In conclusion, oncoprotein HBXIP suppresses miR-18b to elevate MDM2 and activates pAKT to phosphorylate MDM2 for enhancing the interaction between MDM2 and p53, leading to p53 degradation in promotion of breast cancer growth. Our findings shed light on a novel mechanism of p53 down-regulation during the development of breast cancer.

3.
Acta Pharmacol Sin ; 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29925919

RESUMO

We have reported that hepatitis B X-interacting protein (HBXIP, also termed LAMTOR5) can act as an oncogenic transcriptional co-activator to modulate gene expression, promoting breast cancer development. Pyruvate kinase muscle isozyme M2 (PKM2), encoded by PKM gene, has emerged as a key oncoprotein in breast cancer. Yet, the regulatory mechanism of PKM2 is still unexplored. Here, we report that HBXIP can upregulate PKM2 to accelerate proliferation of estrogen receptor positive (ER+) breast cancer. Immunohistochemistry analysis using breast cancer tissue microarray uncovered a positive association between the expression of HBXIP and PKM2. We also discovered that PKM2 expression was positively related with HBXIP expression in clinical breast cancer patients by real-time PCR assay. Interestingly, in ER+ breast cancer cells, HBXIP was capable of upregulating PKM2 expression at mRNA and protein levels in a dose-dependent manner, as well as increasing the activity of PKM promoter. Mechanistically, HBXIP could stimulate PKM promoter through binding to the -779/-579 promoter region involving co-activation of E2F transcription factor 1 (E2F1). In function, cell viability, EdU, colony formation, and xenograft tumor growth assays showed that HBXIP contributed to accelerating cell proliferation through PKM2 in ER+ breast cancer. Collectively, we conclude that HBXIP induces PKM2 through transcription factor E2F1 to facilitate ER+ breast cancer cell proliferation. We provide new evidence for the mechanism of transcription regulation of PKM2 in promotion of breast cancer progression.

4.
J Chromatogr A ; 1537: 10-20, 2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29336808

RESUMO

A simple and effective method of miniaturized solid-phase extraction (mini-SPE) was developed for the simultaneous purification and enrichment of macrolide antibiotics (MACs) (i.e. azithromycin, clarithromycin, erythromycin, lincomycin and roxithromycin) from honey and skim milk. Mesoporous MCM-41 silica was synthesized and used as sorbent in mini-SPE. Several key parameters affecting the performance of mini-SPE procedure were thoroughly investigated, including sorbent materials, amount of sorbent and elution solvents. Under the optimized condition, satisfactory linearity (r2 > 0.99), acceptable precision (RSDs, 0.3-7.1%), high sensitivity (limit of detection in the range of 0.01-0.76 µg/kg), and good recoveries (83.21-105.34%) were obtained. With distinct advantages of simplicity, reliability and minimal sample requirement, the proposed mini-SPE procedure coupled with ultrahigh performance liquid chromatography and quadrupole time-of-flight tandem mass spectrometry could become an alternative tool to analyze the residues of MACs in complex food matrixes.


Assuntos
Análise de Alimentos/métodos , Mel/análise , Macrolídeos/isolamento & purificação , Leite/química , Dióxido de Silício/química , Extração em Fase Sólida/métodos , Animais , Antibacterianos/análise , Antibacterianos/isolamento & purificação , Bovinos , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Macrolídeos/análise , Reprodutibilidade dos Testes , Solventes/análise , Espectrometria de Massas em Tandem
5.
J Chromatogr A ; 1509: 50-59, 2017 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-28645755

RESUMO

Zwitterionic surfactant, used as extractant in microwave-assisted extraction (MAE) was investigated for the first time to extract organic and inorganic iodines from kelp samples. Optimized conditions for the MAE were 200W of microwave irradiation power, 100°C of extraction temperature, 10min of microwave irradiation time, 1g of sample, and 20mL of solvent volume. Ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) was used for the quantitative and qualitative analyses of the iodines. Under the optimum experimental conditions, KI, MIT and DIT were identified in kelp samples, the limits of detection of these analytes were ranged between 3.39 and 6.31ng/mL. The recoveries for spiked samples obtained from different areas were all higher than 92.48%. Compared with the ultrasound-assisted extraction, the proposed method is faster and more effective. Thus, the combination of zwitterionic surfactant-MAE and UHPLC-Q-TOF/MS made up a simple, rapid and effective approach for extraction and determination of iodine compounds in complex seaweed materials.


Assuntos
Fracionamento Químico/métodos , Iodo/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Alga Marinha/química , Tensoativos/química , Verduras/química , Fracionamento Químico/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Iodo/química , Espectrometria de Massas/métodos , Micelas , Micro-Ondas , Extratos Vegetais/química
6.
Acta Pharmacol Sin ; 38(8): 1161-1170, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28603285

RESUMO

Aberrant expression of miR-511 is involved in the development of cancer, but the role of miR-511 in hepatocellular carcinoma (HCC) is not well documented. In this study, we explored the molecular mechanisms of miR-511 in hepatocarcinogenesis. Our results of bioinformatics analysis suggested that B cell translocation gene 1 (BTG1), a member of anti-proliferative gene family, was one of the putative targets of miR-511. The expression levels of miR-511 were significantly higher in 30 clinical HCC tissues than in corresponding peritumor tissues, and were negatively correlated with those of BTG1 in the HCC tissues (r=-0.6105, P<0.01). In human hepatoma cell lines HepG2 and H7402, overexpression of miR-511 dose-dependently inhibited the expression of BTG1, whereas knockdown of miR-511 dose-dependently increased the expression of BTG1. Luciferase reporter gene assays verified that miR-511 targeted the 3'UTR of BTG1 mRNA. In the hepatoma cells, overexpression of miR-511 significantly decreased BTG1-induced G1 phase arrest, which was rescued by overexpression of BTG1. Furthermore, overexpression of miR-511 promoted the proliferation of the hepatoma cells, which was rescued by overexpression of BTG1. Conversely, knockdown of miR-511 inhibited cell proliferation, which was reversed by knockdown of BTG1. In conclusion, miR-511 promotes the proliferation of human hepatoma cells in vitro by targeting the 3'UTR of BTG1 mRNA.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , Regiões 3' não Traduzidas , Western Blotting , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Citometria de Fluxo , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Food Chem ; 226: 141-148, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28254005

RESUMO

A cyclodextrin-based miniaturized solid-phase extraction was developed to extract biopesticides from water and vegetable juices. The analytes were detected by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. In the solid-phase extraction (SPE) procedure, the liquid sample solution is passed through a packed column filled with 40mg of HP-ß-CD, and then the target analytes are absorbed and finally eluted with methanol-acetic acid (90:10, v/v) into a collection tube. The limits of quantification ranged from 3.73 to 16.51ng/mL for a water matrix, from 2.62 to 13.23ng/mL for an orange juice matrix and from 1.76 to 10.35ng/mL for a tomato juice matrix, respectively. The average recovery values were in the range of 88.3-95.9% for the spiked samples. The established methodology was successfully applied to analyze sanguinarine, berberine, rotenone and osthole in water, orange juice and tomato juice.


Assuntos
Agentes de Controle Biológico/química , Cromatografia Líquida de Alta Pressão/métodos , Ciclodextrinas/metabolismo , Sucos de Frutas e Vegetais/microbiologia , Espectrometria de Massas/métodos , Extração em Fase Sólida/métodos , Microbiologia da Água , Agentes de Controle Biológico/análise
8.
Oncotarget ; 8(7): 11063-11070, 2017 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-28052021

RESUMO

BACKGROUND: Previous studies have revealed that hepatitis B core antibody (anti-HBc) levels vary throughout the different phases of treatment-naïve chronic hepatitis B (CHB) patients and can be used as a predictor of treatment response in both interferon-α and nucleoside analogue therapies. However, few data have been published regarding the relationship between quantitative anti-HBc (qAnti-HBc) levels and liver fibrosis in patients with CHB. RESULTS: A total of 489 HBeAg-positive (HBeAg (+)) and 135 HBeAg-negative (HBeAg (-)) patients were recruited. In both HBeAg (+) and HBeAg (-) groups, the S0-1/S0 subjects had significantly lower qAnti-HBc levels than the S2-4 subjects (p < 0.05). Multiple logistic regression analysis showed that the parameters for predicting significant fibrosis (S ≥ 2) included age, PLT and qAnti-HBc. In HBeAg (+) subjects, the AUROC of qAnti-HBc for predicting significant fibrosis was 0.734 (95% CI 0.689 to 0.778) and the optimal cut-off was 4.58 log10IU/mL, with a sensitivity of 63.08% and a specificity of 74.83%. In HBeAg (-) subjects, the AUROC was 0.707 (95% CI 0.612 to 0.801) and the optimal cut-off value was 4.37 log10IU/mL, with a sensitivity of 75.53% and a specificity of 56.10%. MATERIALS AND METHODS: From 2012 to 2015, we conducted a cross-sectional study of treatment-naïve CHB patients. Liver biochemistry, hepatitis B virus (HBV) serological markers, HBV DNA, hepatitis B surface antigen (HBsAg) titers and HBV genotype were determined using commercial assays, and serum qAnti-HBc levels were measured using double-sandwich immunoassay. Liver biopsies and serum samples were obtained on the same day. CONCLUSIONS: The present study showed an association between high serum qAnti-HBc levels and significant fibrosis (S ≥ 2) in treatment-naïve CHB patients. Furthermore, we described a serum qAnti-HBc cut-off for predicting significant fibrosis in CHB patients infected with HBV genotype B or C.


Assuntos
Anticorpos Anti-Hepatite B/imunologia , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Cirrose Hepática/imunologia , Adulto , Estudos Transversais , Feminino , Genótipo , Anticorpos Anti-Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Modelos Logísticos , Masculino , Prognóstico , Curva ROC , Adulto Jovem
9.
Molecules ; 22(1)2017 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-28106847

RESUMO

Cornus officinalis and Dioscorea opposita are two traditional Chinese medicines widely used in China for treating diabetes mellitus and its complications, such as diabetic cardiomyopathy. Morroniside (Mor) of Cornus officinalis and diosgenin (Dio) of Dioscorea opposita formed an innovative formula named M + D. The aims of the present study were to investigate myocardial protective effect of M + D on diabetic cardiomyopathy (DCM) through the inhibition of expression levels of caspase-3 protein, and identify the advantage of M + D compared with Mor, Dio, and the positive drug metformin (Met). We detected cell viability, cell apoptosis, intracellular reactive oxygen species (ROS) levels, and the expression levels of Bcl-2, Bax, and caspase-3 protein in rat cardiomyocytes. In result, Mor, Dio, and M + D increased cell viability, inhibited cell apoptosis and decreased ROS levels. Additionally, the expression of Bax and Bcl-2 protein was modulated and the expression levels of caspase-3 protein were markedly decreased. Among the treatment groups, M + D produced the most prominent effects. In conclusion, our data showed for the first time that Mor, Dio, and M + D prevented high glucose (HG)-induced myocardial injury by reducing oxidative stress and apoptosis in rat cardiomyocytes. Among all the groups, M + D produced the strongest effect, while Mor and Dio produced weaker effects.


Assuntos
Diosgenina/farmacologia , Glucose/toxicidade , Glicosídeos/farmacologia , Miócitos Cardíacos/citologia , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Sobrevivência Celular , Células Cultivadas , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/prevenção & controle , Combinação de Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
10.
Chin J Integr Med ; 23(3): 208-214, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28004300

RESUMO

OBJECTIVES: To study the effect of Wenhua Juanbi Recipe (, WJR) on expression of receptor activator of nuclear factor kappa B ligand (RANKL), osteoprotegerin (OPG), and tumor necrosis factor receptor superfamily member 14 (TNFRSF14, also known as LIGHT) in rats with collagen-induced arthritis (CIA). METHODS: CIA rats were generated by subcutaneous injection of bovine collagen type-II at the tail base. Sixty CIA rats were randomly assigned (10 animals/group) to: model, methotrexate (MTX)-treated (0.78 mg/kg body weight), and WJR-treated (22.9 g/kg) groups. Healthy normal rats (n=10) were used as the normal control. Treatments or saline were administered once daily by oral gavage. Rats were sacrifificed at day 28 post-treatment and knee synovium and peripheral blood serum were collected. Toe swelling degree and expression of RANKL, OPG, and LIGHT were determined by Western blot and immunohistochemistry. RESULTS: Compared with the normal group, toe swelling degree was signifificantly increased in the model group (P<0.01). After treatment, toe swelling degree decreased signifificantly in the WJR and MTX groups compared with the model group (P<0.01). Compared with the normal group, expression of RANKL and LIGHT were signifificantly increased and OPG signifificantly decreased in peripheral blood and synovium of the model group (P<0.01). Conversely, RANKL and LIGHT expression were signifificantly reduced and OPG increased in the WJR and MTX groups compared with the model group (P<0.01). No statistically significant difference existed between WJR and MTX groups. CONCLUSION: WJR likely acts by reducing RANKL expression and increasing OPG expression, thus inhibiting RANKL/RANK interaction and reducing LIGHT expression, thereby inhibiting osteoclast formation/activation to block bone erosion.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Medicamentos de Ervas Chinesas/uso terapêutico , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Membro 14 de Receptores do Fator de Necrose Tumoral/metabolismo , Animais , Western Blotting , Bovinos , Medicamentos de Ervas Chinesas/farmacologia , Imuno-Histoquímica , Masculino , Ratos Wistar , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/patologia
11.
Electrophoresis ; 37(23-24): 3118-3125, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27699822

RESUMO

A simple, efficient, and green chitosan-assisted liquid-solid extraction method was developed for the sample preparation of isoquinoline derivative alkaloids followed by microemulsion LC. The optimized mobile phase consisted of 0.8% w/v of ethyl acetate, 1.0% w/v of SDS, 8.0% w/v of n-butanol, 0.1% v/v acetic acid, and 10% v/v ACN. Compared to pharmacopoeia method and organic solvent extraction, this new approach avoided the use of volatile organic solvents, replacing them with relatively small amounts of chitosan. Under the optimum conditions, good linearity (r2 > 0.9980) for all calibration curves and low detection limits between 0.05 and 0.10 µg/mL were achieved. The presented procedure was successfully applied to determine alkaloids in Rhizoma coptidis with satisfactory recoveries (81.3-106.4%).


Assuntos
Alcaloides/análise , Quitosana/química , Cromatografia Líquida/métodos , Isoquinolinas/análise , Microextração em Fase Líquida/métodos , Alcaloides/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Isoquinolinas/isolamento & purificação , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
12.
Medicine (Baltimore) ; 95(34): e4422, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27559949

RESUMO

Previous studies have shown that hepatitis B core antibody (anti-HBc) levels vary during different phases of disease in treatment-naïve chronic hepatitis B (CHB) patients and can be used as a predictor of both interferon-α and nucleoside analogue therapy response. However, there is no information on the association between the quantitative serum anti-HBc (qAnti-HBc) level and liver inflammation in CHB patients. Therefore, we investigated these relationships in a large cohort of treatment-naïve CHB patients. A total of 624 treatment-naïve CHB patients were included in the study. The serum qAnti-HBc level was moderately correlated with ALT and AST levels (P < 0.001) in both hepatitis B e antigen-positive (HBeAg [+]) and HBeAg-negative (HBeAg [-]) CHB patients. CHB patients with no to mild inflammation (G0-1) had significantly lower serum qAnti-HBc levels than patients with moderate to severe inflammation (G2-4) (P < 0.001). Receiver operating characteristic analysis suggested that a serum qAnti-HBc cut-off value of 4.36 log10 IU/mL provided a sensitivity of 71.68%, specificity of 73.81%, positive predictive value of 78.43%, and negative predictive value of 66.24% in HBeAg (+) CHB patients with moderate to severe inflammation (G≥2). A cut-off value of 4.62 log10 IU/mL provided a sensitivity of 54.29%, specificity of 90.00%, positive predictive value of 95.00%, and negative predictive value of 36.00% in HBeAg (-) CHB patients with moderate to severe inflammation (G≥2). Serum qAnti-HBc levels were positively associated with liver inflammation grade. Furthermore, we identified optimal serum qAnti-HBc cut-off values for the prediction of inflammation activity in both HBeAg (+) and HBeAg (-) treatment-naïve CHB patients.


Assuntos
Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Hepatite B Crônica/sangue , Hepatite B Crônica/patologia , Índice de Gravidade de Doença , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Feminino , Genótipo , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Adulto Jovem
13.
Acta Pharmacol Sin ; 37(7): 898-907, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27133296

RESUMO

AIM: Increasing evidence shows that mRNAs exert regulatory function along with coding proteins. Recently we report that a hairpin within YAP mRNA 3'UTR can modulate the Hippo signaling pathway. PTEN is a tumor suppressor, and is mutated in human cancers. In this study we examined whether PTEN mRNA 3'UTR contained a hairpin structure that could regulate gene regulation at the post-transcriptional level. METHODS: The secondary structure of PTEN mRNA 3'UTR was analyzed using RNAdraw and RNAstructure. Function of hairpin structure derived from the PTEN mRNA 3'UTR was examined using luciferase reporter assay, RT-PCR and Western blotting. RNA-immunoprecipitation (RIP) assay was used to analyze the interaction between PTEN mRNA and microprocessor Drosha and DGCR8. Endogenous siRNA (esiRNA) derived from PTEN mRNA 3'UTR was identified by RT-PCR and rt-PCR, and its target genes were predicted using RNAhybrid. RESULTS: A bioinformatics analysis revealed that PTEN mRNA contained a hairpin structure (termed PTEN-sh) within 3'UTR, which markedly increased the reporter activities of AP-1 and NF-κB in 293T cells. Moreover, treatment with PTEN-sh (1 and 2 µg) dose-dependently inhibited the expression of PTEN in human liver L-O2 cells. RIP assay demonstrated that the microprocessor Drosha and DGCR8 was bound to PTEN-sh in L-O2 cells, leading to the cleavage of PTEN-sh from PTEN mRNA 3'UTR. In addition, microprocessor Dicer was involved in the processing of PTEN-sh. Interestingly, esiRNA (termed PTEN-sh-3p21) cleaved from PTEN-sh was identified in 293T cells and human liver tissues, which was found to target the mRNA 3'UTRs of protein phosphatase PPP2CA and PTEN in L-O2 cells. Treatment of L-O2 or Chang liver cells with PTEN-sh-3p21 (50, 100 nmol/L) promoted the cell proliferation in dose- and time-dependent manners. CONCLUSION: The endogenous siRNA (PTEN-sh-3p21) cleaved from PTEN-sh within PTEN mRNA 3'UTR modulates PPP2CA and PTEN at the post-transcriptional level in liver cells.


Assuntos
Regiões 3' não Traduzidas/genética , Hepatócitos/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Proteína Fosfatase 2/metabolismo , Processamento Pós-Transcricional do RNA , RNA Interferente Pequeno/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , RNA Helicases DEAD-box/metabolismo , Relação Dose-Resposta a Droga , Hepatócitos/enzimologia , Humanos , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/metabolismo , Ribonuclease III/metabolismo
14.
Electrophoresis ; 37(13): 1891-901, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27060460

RESUMO

A novel dispersive micro-SPE method with trace poly-ß-CD wrapped multiwalled carbon nanotubes as sorbents was applied to extract flavonoids in honey samples. The analytes were then determined by CE with LED-induced fluorescence detection. The influencing parameters, such as the sorbent concentration, extraction time, and eluent type, were properly optimized. The established method had the advantages of simplicity, low consumption of sorbent amount (0.009 mg) and organic solvent (100 µL), and high sensitivity, meeting the principle of green chemistry. Under the optimum conditions, the sorbents allowed the extraction and preconcentration of the flavonoids with enrichment factors in the range from 78 to 166. The recovery study performed at two different fortification levels provided an average recovery >91%. LODs for all the compounds ranged from 0.07 to 17.99 ng/mL. These results demonstrated that the proposed method could be used as a convenient and efficient extraction technique for analysis of flavonoids in different honey matrices.


Assuntos
Eletroforese Capilar/métodos , Flavonoides/isolamento & purificação , Mel/análise , Nanotubos de Carbono , Espectrometria de Fluorescência/métodos , beta-Ciclodextrinas/análise , Adsorção , Limite de Detecção , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Peso Molecular , Extração em Fase Sólida/métodos
15.
Food Chem ; 204: 167-75, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26988490

RESUMO

In this work, two flavonoid glycosides (neohesperidin and naringin) in lime fruit were effectively extracted by miniaturized matrix solid phase dispersion (MSPD), followed by ultra-performance liquid chromatography-ultraviolet detection. The best results were obtained using Florisil (150mg) as the sorbent and 1-butyl-3-methylimidazolium tetrafluoroborate (0.4mL, 250mM) as the elution solvent. This work represents the first attempt of using ionic liquids as a green eluent for extraction of the investigated compounds in miniaturized MSPD. Compared with the conventional methods, the proposed method is advantageous due to improved enrichment factor and reduced reagent consumption. A good linearity was observed with r(2) values (>0.998). Meanwhile, the method gave acceptable recoveries (90.16-96.47%) for the determination of flavonoids in plant samples. The limits of detection of the two analytes ranged between 4.08 and 5.04µg/g. The results showed that the optimized method has a great potential for sample preparation in routine analysis of complex plant samples.


Assuntos
Citrus aurantiifolia/química , Flavanonas/análise , Hesperidina/análogos & derivados , Líquidos Iônicos/química , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Hesperidina/análise , Imidazóis/química , Extração em Fase Sólida/métodos , Solventes/química
16.
Food Chem ; 190: 474-480, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26212999

RESUMO

A simple, rapid, and highly selective trace matrix solid phase dispersion (MSPD) technique, coupled with ultra-performance liquid chromatography-ultraviolet detection, was proposed for extracting flavonoids from orange fruit peel matrices. Molecular sieve SBA-15 was applied for the first time as a solid support in trace MSPD. Parameters, such as the type of dispersant, mass ratio of the sample to the dispersant, grinding time, and elution pH, were optimized in detail. The optimal extraction conditions involved dispersing a powdered fruit peel sample (25 mg) into 25mg of SBA-15 and then eluting the target analytes with 500 µL of methanol. A satisfactory linearity (r(2) > 0.9990) was obtained, and the calculated limits of detection reached 0.02-0.03 µg/mL for the compounds. The results showed that the method developed was successfully applied to determine the content of flavonoids in complex fruit peel matrices.


Assuntos
Cromatografia Líquida/métodos , Flavonoides/análise , Frutas/química , Extração em Fase Sólida/métodos , Limite de Detecção , Dióxido de Silício/química
17.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(10): 1219-1223, 2016 10.
Artigo em Chinês | MEDLINE | ID: mdl-30641010

RESUMO

Objective To observe the effect of Wenhua Juanbi Recipe (WJR) on the expres- sions of DNA methyltransferases (DNMTs) in peripheral blood mononuclear cells (PBMCs) of collagen- inducing arthritis (CIA) , and to study its mechanism for treating CIA. Methods Totally 90 Wistar rats were randomly divided into the model group (n =80) and the normal control group (n = 10). Rats of the model group were injected with type II collagen of bovine (BC II) emulsion from the tail to establish CIA model. Successfully modeled 50 CIA rats were randomly divided into five groups, i.e., the model group, the methotrexate (MTX) group, the low dose WJR group, the middle dose WJR group, the high dose WJR group, 10 in each group. Rats in the model group were administered with normal saline by gastrogavage, once per day. Rats in low, middle, and high dose WJR groups were administered with WJR by gas- trogavage at the daily dose of 22. 9, 45. 8, 68. 7 g/kg, respectively (once per day). Rats in the MTX group were administered with MTX suspension (0.78 mg/kg) by gastrogavage, once per week for 30 successive days. The paw swelling was evaluated using volume method (draining volume). PBMCs were extrac- ted from each group after intervention. mRNA expression levels of DNMTs (DNMT1 , DNMT3a, DNMT3b) were detected by real-time quantitative PCR. Results Compared with the normal group, the paws were obviously swollen in the model group (P <0. 01). Compared with the model group, swollen paws were obviously alleviated in low, middle, and high dose WJR groups, and the MTX group (P <0.01). Compared with before treatment in the same group, swollen paws were obviously alleviated in low, middle, and high dose WJR groups, and the MTX group (P <0. 01 ). Compared with the normal group, expression levels of DNMT1, DNMT3a, and DNMT3b in PBMCs were obviously lowered in the model group (P <0.01). Compared with the model group, expression levels of DNMT1 , DNMT3a, DNMT3b in PBMCs were obviously elevated in low, middle, and high dose WJR groups, and the MTX group (all P <0. 01). There was no sig- nificant difference in expression levels of DNMT1, DNMT3a, or DNMT3b in PBMCs among low, middle, and high dose WJR groups (P>0.05). Conclusions Expression levels of DNMTs in PBMCs of CIA rats decreased. WJR up-regulated the expression level of DNMTs in PBMCs of CIA rats in no obvious dose de- pendent way. One of WJR's mechanisms for treating CIA might be up-regulating expression levels of DN- MTs, and adjusting the state of DNA methylation.


Assuntos
Artrite , Metilação de DNA , Metilases de Modificação do DNA , Leucócitos Mononucleares , Animais , Artrite/tratamento farmacológico , Artrite/metabolismo , Bovinos , Colágeno , DNA , Metilação de DNA/efeitos dos fármacos , Metilases de Modificação do DNA/efeitos dos fármacos , Metilases de Modificação do DNA/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Ratos , Ratos Wistar
18.
Electrophoresis ; 36(23): 2951-60, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26332895

RESUMO

This article describes the use of the mesoporous molecular sieve KIT-6 as a sorbent in miniaturized matrix solid-phase dispersion (MSPD) in combination with ultra-performance LC for the determination of bioactive flavonoids in toothpaste, Scutellariae Radix, and saliva. In this study, for the first time, KIT-6 was used as a sorbent material for this mode of extraction. Compared with common silica-based sorbents (C18 and activated silica gel), the proposed KIT-6 dispersant with a three-dimensional cubic Ia3d structure and highly ordered arrays of mesoporous channels exhibits excellent adsorption capability of the tested compounds. In addition, several experimental variables, such as the mass ratio of sample to dispersant, grinding time, and elution solvent, were optimized to maximize the extraction efficiency. The proposed analytical method is simple, fast, and entails low consumption of samples, dispersants and elution solvents, thereby meeting "green chemistry" requirements. Under the optimized conditions, the recoveries of three bioactive flavonoids obtained by analyzing the spiked samples were from 89.22 to 101.17%. Also, the LODs and LOQs for determining the analytes were in the range of 0.02-0.04 µg/mL and 0.07-0.13 µg/mL, respectively. Finally, the miniaturized matrix solid-phase dispersion method was successfully applied to the analysis of target solutes in real samples, and satisfactory results were obtained.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Extração em Fase Sólida/métodos , Cremes Dentais/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Miniaturização , Plantas/química , Saliva/química , Dióxido de Silício , Extração em Fase Sólida/instrumentação , Solventes/química , Raios Ultravioleta
19.
J Chromatogr A ; 1409: 11-8, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26209194

RESUMO

A novel dispersive micro-solid-phase extraction (DMSPE) method using ultramicro chitosan as an adsorbent was proposed for the analysis of flavonols in Flos Sophorae tea, with detection by ultra-high performance liquid chromatography. Various parameters affecting the extraction recovery, including the concentration and viscosity of chitosan, extraction time and the pH of the sample solution were investigated and optimized. The optimized conditions were found to be 0.4µg/mL of sorbent, pH of 7, an extraction time of 1.0min and 100µL of methanol as the elution solvent. The DMSPE method showed excellent linearity (r(2)>0.99) with pre-concentration factor values ranging from 23 to 77-fold. The limits of detection and quantification were 0.22-0.36ng/mL and 0.72-1.21ng/mL, respectively. This method was successfully applied to the analysis of flavonols in Flos Sophorae tea samples, and their recoveries were in the range of 95.2-102.4%.


Assuntos
Bebidas/análise , Quitosana/química , Flavonóis/isolamento & purificação , Extração em Fase Sólida/métodos , Sophora/química , Cromatografia Líquida de Alta Pressão , Seringas
20.
J Chromatogr A ; 1406: 68-77, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26129982

RESUMO

An analytical procedure based on miniaturized solid phase extraction (SPE) and ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was developed and validated for determination of six flavanones in Citrus fruits. The mesoporous molecular sieve SBA-15 as a solid sorbent was characterised by Fourier transform-infrared spectroscopy and scanning electron microscopy. Additionally, compared with reported extraction techniques, the mesoporous SBA-15 based SPE method possessed the advantages of shorter analysis time and higher sensitivity. Furthermore, considering the different nature of the tested compounds, all of the parameters, including the SBA-15 amount, solution pH, elution solvent, and the sorbent type, were investigated in detail. Under the optimum condition, the instrumental detection and quantitation limits calculated were less than 4.26 and 14.29ngmL(-1), respectively. The recoveries obtained for all the analytes were ranging from 89.22% to 103.46%. The experimental results suggested that SBA-15 was a promising material for the purification and enrichment of target flavanones from complex citrus fruit samples.


Assuntos
Cromatografia Líquida de Alta Pressão , Citrus/química , Flavanonas/análise , Análise de Alimentos/métodos , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Sensibilidade e Especificidade , Dióxido de Silício , Solventes/química
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