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1.
Langmuir ; 39(51): 18815-18824, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38088351

RESUMO

Cationic surfactant-stabilized oil-in-water emulsions pose a significant challenge in separation due to the presence of surfactants. Herein, we develop a collagen-fiber-based CFM-PMDA-TiO2 membrane with unique infiltration properties capable of efficiently separating cationic surfactant-stabilized oil-in-water emulsions by exploiting the charge-demulsification effect. The membrane exhibits superhydrophilic and submerged superoleophobic properties, making it highly suitable for separating a wide range of commercially available cationic surfactant-stabilized oil-in-water microemulsions and nanoemulsions, which demonstrates an exceptional separation efficiency as high as 99.86% and an impressive flux of up to 1436.40 L m-2 h-1. Furthermore, even after a strong subjecting of the membrane to sandpaper abrasion and a full 15 time use, the separation efficacy of oil-in-water emulsions is retained, highlighting the durability, reusability, and economic viability. We propose that these features are enabled by the electrostatic interactions triggered from pyromellitic dianhydride (PMDA) and superhydrophilic-superoleophobic membrane intensified by the TiO2 on the unique collagen fiber membrane. Outcomes emphasize the versatility and potential of our membrane in addressing emulsified oily wastewater hurdles.

2.
J Org Chem ; 88(13): 9187-9198, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37291966

RESUMO

Direct access to substituted dihydrochalcones from the easily available starting materials 3-hydroxypropionitrile derivatives and arylboronic acids is described. The procedure involves a multicomponent aryl addition/hydroxyl elimination/reduction Heck approach in the presence of a Pd catalyst with excellent functional group tolerance and a wide range of substrates. In addition, mixed 1,3-diarylation of 3-hydroxypropanenitrile using two arylboronic acids with different electronic properties was also achieved.


Assuntos
Ácidos Borônicos , Paládio , Paládio/química , Estrutura Molecular , Ácidos Borônicos/química , Catálise
3.
Ecotoxicol Environ Saf ; 263: 115364, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37586198

RESUMO

As the cheap and efficient catalysts, the iron-based catalysts have been considered as one of the most promising catalysts for peroxydisulfate (PDS) activation and the development of high-performance iron-based catalysts are attracting growing attentions. In this work, a magnetic Fe-based catalysts (Fe/NC-1000) was obtained by using Fe modified ZIF-8 as the precursor and used to activate the PDS for the degradation of perfluorooctane sulphonate (PFOS). Morphology and structure analysis showed that the resulted Fe/NC-1000 catalyst was displayed porous spheres (40-60 nm) and mainly composed of Fe0, FeNx and carbon. When Fe/NC-1000 was employed to activate the PDS (0.1 g/L of catalyst dosage, 0.5 g/L of PDS dosage and at initial pH of 4.6), the Fe/NC-1000/PDS system exhibited excellent efficiency (97.9 ± 0.1) % for PFOS (10 mg/L) degradation within 30 min. The quenching tests and EPR results revealed that the Fe/NC-1000/PDS system degraded PFOS primarily through singlet oxygen (1O2) evolution and electron-transfer process. Besides, based on the degradation byproducts determined by LC-MS-MS, the PFOS first occurred de-sulfonation to form PFOA, and then the resulted PFOA underwent stepwise defluorination in the Fe/NC-1000/PDS system. Density Functional Theory (DFT) calculations and electrochemistry tests strongly confirmed that Fe/NC-1000 exhibited high electron transfer efficiency, resulting in promoted performance on activating PDS. Importantly, the results of Ecological Structure-Activity Relationship (ECOSAR) analysis showed that the intermediates were lowly toxic during the PFOS degradation, manifesting a green process for PFOS removal. This study would provide more understandings for the persulfate activation process mediated by Fe-based catalysts for Perfluorinated alkyl substances (PFAS) elimination.


Assuntos
Fluorocarbonos , Ferro , Ferro/química , Eletroquímica , Oxigênio Singlete , Catálise
4.
J Environ Manage ; 337: 117658, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37011477

RESUMO

There are approximately 4 billion tons of uranium in the ocean, which is unmatched by the surface. Nevertheless, it's very challenging to extract uranium from the ocean due to the exceedingly low concentration of uranium in the ocean (about 3.3 µg L-1) as well as high salinity level. Current methods are often limited by selectivity, sustainability, economics, etc. Herein, phosphoric acid group and amidoxime group were grafted to skin collagen fibers through " initiated access" to design a new uranium extraction material, abbreviated as CGPA. Through laboratory simulation experiments, it is concluded that the maximum adsorption capacity of CGPA for uranium reaches 263.86 mg g-1. It has high adsorption, selectivity, and reusability for uranium. In the actual seawater extraction experiment, CGPA obtained 29.64 µg of uranium after extracting 10.0 L of seawater, and the extraction rate was 90.1%. The adsorbent has excellent effects in kinetics, selectivity, extraction capacity, renewability, etc. In the extraction of uranium from seawater, and is an economically feasible and industrially expandable adsorbent.


Assuntos
Urânio , Fosfatos , Biomassa , Água do Mar , Adsorção
5.
Molecules ; 28(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37959831

RESUMO

Rhodiola rosea L. (RRL) is a popular plant in traditional medicine, and Rosavin, a characteristic ingredient of RRL, is considered one of the most important active ingredients in it. In recent years, with deepening research on its pharmacological actions, the clinical application value and demand for Rosavin have been steadily increasing. Various routes for the extraction and all-chemical or biological synthesis of Rosavin have been gradually developed for the large-scale production and broad application of Rosavin. Pharmacological studies have demonstrated that Rosavin has a variety of biological activities, including antioxidant, lipid-lowering, analgesic, antiradiation, antitumor and immunomodulation effects. Rosavin showed significant therapeutic effects on a range of chronic diseases, including neurological, digestive, respiratory and bone-related disorders during in vitro and vivo experiments, demonstrating the great potential of Rosavin as a therapeutic drug for diseases. This paper gives a comprehensive and insightful overview of Rosavin, focusing on its extraction and synthesis, pharmacological activities, progress in disease-treatment research and formulation studies, providing a reference for the production and preparation, further clinical research and applications of Rosavin in the future.


Assuntos
Extratos Vegetais , Rhodiola , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Dissacarídeos/farmacologia , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico
6.
Molecules ; 28(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38005313

RESUMO

A boron and iron co-doped biochar (B-Fe/biochar) from Masson pine bark was fabricated and used to activate peroxydisulfate (PDS) for the degradation of guaiacol (GL). The roles of the dopants and the contribution of the radical and non-radical oxidations were investigated. The results showed that the doping of boron and iron significantly improved the catalytic activity of the biochar catalyst with a GL removal efficiency of 98.30% within 30 min. The degradation of the GL mainly occurred through the generation of hydroxyl radicals (·OHs) and electron transfer on the biochar surface, and a non-radical degradation pathway dominated by direct electron transfer was proposed. Recycling the B-Fe/biochar showed low metal leaching from the catalyst and satisfactory long-term stability and reusability, providing potential insights into the use of metal and non-metal co-doped biochar catalysts for PDS activation.


Assuntos
Boro , Casca de Planta , Carvão Vegetal , Ferro
7.
Environ Res ; 194: 110652, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33417907

RESUMO

In this work, a novel cellulose aerogel (CNC-PVAm/rGO) was fabricated using cellulose nanocrystalline (CNC) modified with polyvinylamine (PVAm) and reduced graphene oxide (rGO). The resultant CNC-PVAm/rGO was then applied for the adsorption of diclofenac sodium (DCF), a typical non-steroidal anti-inflammatory drug. Characterization using ultra-high-resolution field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and the Brunauer-Emmett-Teller surface area revealed that the obtained CNC-PVAm/rGO displayed an evident 3D porous structure, which had an ultralight weight, good recovery, abundant surface functional groups (e.g., -NH2 and -OH), and rGO nanosheets. In addition, the material presented a stable crystal structure and large specific surface area (105.73 m2 g-1). During the adsorption of DCF, the CNC-PVAm/rGO aerogel showed a rather excellent adsorption performance, with a maximum adsorption capacity (qmax) of 605.87 mg g-1, which was approximately 53 times larger than that of the bare CNC aerogel (11.45 mg g-1). The adsorption performance of CNC-PVAm/rGO was also better than that of other reported adsorbents. The adsorption of DCF to CNC-PVAm/rGO obeyed the Langmuir isotherm and pseudo-second-order kinetic models, and underwent a spontaneous exothermic process. Moreover, DCF was easily desorbed from CNC-PVAm/rGO with sodium hydroxide solution (0.1 mol L-1), and the absorbent could be reused four times. The introduction of PVAm and rGO to the CNC-PVAm/rGO aerogel also greatly enhanced electrostatic interactions, π-π interactions, and hydrophobic effects. These enhancements significantly promoted the hydrogen bonding interactions between the DCF molecules and CNC-PVAm/rGO, thus resulting in a large improvement in the adsorption performance of the aerogel.


Assuntos
Celulose , Diclofenaco , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Água
8.
J Neuroinflammation ; 17(1): 18, 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31926553

RESUMO

BACKGROUND: Microglial activation is a prominent feature of neuroinflammation, which is present in almost all neurodegenerative diseases. While an initial inflammatory response mediated by microglia is considered to be protective, excessive pro-inflammatory response of microglia contributes to the pathogenesis of neurodegeneration. Although autophagy is involved in the suppression of inflammation, its role and mechanism in microglia are unclear. METHODS: In the present study, we studied the mechanism by which lipopolysaccharide (LPS) affects microglial autophagy and the effects of autophagy on the production of pro-inflammatory factors in microglial cells by western blotting, immunocytochemistry, transfection, transmission electron microscopy (TEM), and real-time PCR. In a mouse model of neuroinflammation, generated by intraventricular injection of LPS (5 µg/animal), we induced autophagy by rapamycin injection and investigated the effects of enhanced autophagy on microglial activation by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry. RESULTS: We found that autophagic flux was suppressed in LPS-stimulated N9 microglial cells, as evidenced by decreased expression of the autophagy marker LC3-II (lipidated form of MAP1LC3), as well as increased levels of the autophagy adaptor protein SQSTM1. LPS significantly decreased Vps34 expression in N9 microglial cells by activating the PI3KI/AKT/MTOR pathway without affecting the levels of lysosome-associated proteins and enzymes. More importantly, overexpression of Vps34 significantly enhanced the autophagic flux and decreased the accumulation of SQSTM1 in LPS-stimulated N9 microglial cells. Moreover, our results revealed that an LPS-induced reduction in the level of Vps34 prevented the maturation of omegasomes to phagophores. Furthermore, LPS-induced neuroinflammation was significantly ameliorated by treatment with the autophagy inducer rapamycin both in vitro and in vivo. CONCLUSIONS: These data reveal that LPS-induced neuroinflammation in N9 microglial cells is associated with the inhibition of autophagic flux through the activation of the PI3KI/AKT/MTOR pathway, while enhanced microglial autophagy downregulates LPS-induced neuroinflammation. Thus, this study suggests that promoting the early stages of autophagy might be a potential therapeutic approach for neuroinflammation-associated diseases.


Assuntos
Autofagossomos/imunologia , Classe III de Fosfatidilinositol 3-Quinases/metabolismo , Inflamação/imunologia , Microglia/imunologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Autofagossomos/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Autofagia/imunologia , Linhagem Celular , Classe III de Fosfatidilinositol 3-Quinases/imunologia , Regulação para Baixo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/imunologia
9.
Nano Lett ; 18(10): 6301-6311, 2018 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-30240228

RESUMO

Efficient small interfering RNA (siRNA) delivery in the presence of serum is of crucial importance for effective gene therapy. Fluorinated vectors are considered to be attractive candidates for siRNA-mediated gene therapy because of their delivery efficacy in serum-containing media. However, the mechanisms driving the superior gene transfection behavior of fluorinated vectors are still not well-understood, and comprehensive investigations are warranted. Herein, we fabricated a library of perfluorooctanoyl fluoride-fluorinated (PFF-fluorinated) oligoethylenimines (f xOEIs, x is the PFF:OEI feeding ratio), which can readily form nanoassemblies (f xOEI NAs) capable of efficient siRNA delivery in cells cultured in medium both devoid of and supplemented with fetal bovine serum (FBS). The gene silencing test in serum-containing medium revealed that the f0.7OEI/siRNA NAs achieved a luciferase silencing of ∼88.4% in Luc-HeLa cells cultured in FBS-containing medium, which was almost 2-fold greater than the silencing efficacy of siRNA delivered by the commercially available vector Lipo 2000 (∼48.8%). High levels of apolipoprotein B silencing were also achieved by f0.7OEI/siRNA NAs in vivo. For an assessment of the underlying mechanisms of the efficacy of gene silencing of fluorinated vectors, two alkylated OEIs, aOEI-C8 and aOEI-C12, were fabricated as controls with similar molecular structure and hydrophobicity to that of f0.7OEI, respectively. In vitro investigations showed that the superior gene delivery exhibited by f0.7OEI NAs derived from the potent endosomal disruption capability of fluorinated vectors in the presence of serum, which was essentially attributed to the serum protein adsorption resistance of the f0.7OEI NAs. Therefore, this work provides an innovative approach to siRNA delivery as well as insights into fluorine-associated serum resistance.

10.
Biochim Biophys Acta Mol Basis Dis ; 1864(3): 793-803, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29253515

RESUMO

The involvement of the tumor stromal cells in acquired resistance of non-small cell lung cancers (NSCLCs) to tyrosine kinase inhibitors (TKIs) has previously been reported, but the precise mechanism remains unclear. In the present study, we investigated the role and mechanism underlying Cancer-associated fibroblasts (CAFs) in TKI resistance of NSCLCs. In vitro and in vivo experiments showed that HCC827 and PC9 cells, non-small cell lung cancer cells with EGFR-activating mutations, became resistant to the EGFR-TKI gefitinib when cultured with CAFs isolated from NSCLC tissues. Moreover, we showed that CAFs could induce epithelial-mesenchymal transition (EMT) phenotype of HCC827 and PC9 cells, with an associated change in the expression of epithelial to mesenchymal transition markers. Using proteomics-based method, we identified that CAFs significantly increased the expression of the Annexin A2 (ANXA2). More importantly, knockdown of ANXA2 completely reversed EMT phenotype and gefitinib resistance induced by CAFs. Furthermore, we found that CAFs increased the expression and phosphorylation of ANXA2 by secretion of growth factors HGF and IGF-1 and by activation of the corresponding receptors c-met and IGF-1R. Dual inhibition of HGF/c-met and IGF-1/IGF-1R pathways could significantly suppress ANXA2, and markedly reduced CAFs-induced EMT and gefitinib resistance. Taken together, these findings indicate that CAFs promote EGFR-TKIs resistance through HGF/IGF-1/ANXA2/EMT signaling and may be an ideal therapeutic target in NSCLCs with EGFR-activating mutations.


Assuntos
Antineoplásicos/uso terapêutico , Fibroblastos Associados a Câncer/fisiologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Anexina A2/metabolismo , Fibroblastos Associados a Câncer/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Células Cultivadas , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos SCID , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Chemistry ; 24(43): 10953-10958, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29900598

RESUMO

Superhydrophobic materials hold great promise in emulsion separation, but they have inherent mechanical weakness and are ineffective to separate mixed surfactant-stabilized emulsions. Herein, we combined the adhesion ability of polyphenol-Fe3+ bis-complexes with the high mechanical strength of carbon nanotubes (CNTs) to construct a mechanically robust and superhydrophobic coating on a collagen fiber membrane (CFM). We demonstrated that both CNTs and polyphenolic complexes competed with the surfactants adsorbed onto the emulsion droplets, serving as efficient demulsifiers to various mixed surfactant-stabilized emulsions. CFM has a 3D fibrous structure and a high limiting oxygen index, which provides high flux and flame resistance. The as-prepared superhydrophobic membrane can separate diverse anionic/nonionic and cationic/nonionic surfactant-stabilized micro- and nanoemulsions under gravity, with a separation efficiency and flux up to 99.999 % and 1695 L m-2 h-1 , respectively. The membranes also retained the emulsion separation ability after sandpaper abrasion. These features demonstrate a practical technology for emulsion separation.

12.
BMC Cancer ; 18(1): 1023, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30348132

RESUMO

BACKGROUND: Tumor suppressor gene p16 promoter hypermethylation has been widely studied in colorectal cancer (CRC), yet its clinicopathological significance remains controversial. The methylation alterations of other regions within p16 gene are still rarely researched. The present study aimed to explore the methylation changes of p16 gene body in CRC and to find whether they were associated with clinicopathological staging of CRC. METHODS: Paired colorectal cancer tissues and corresponding adjacent normal tissues from 30 CRC patients were collected. The methylation levels of two CpG islands within p16 gene body, exon 1 and exon 2, were accurately assessed simultaneously by a LC-MS/MS method. The p16 protein expressions were assessed by immunohistochemistry assay. Statistical analyses were carried out using SPSS 17.0 software. Heat-map analysis was carried out by HemI 1.0 software. RESULTS: In the present study, CRC tissues showed more highly methylated than adjacent normal tissues at both CpG islands of p16 gene. And exon 2 hypermethylation was higher and more frequent than exon 1. The ROC curve analysis showed that the simultaneous use of both indicators had excellent sensitivity and specificity for distinguishing CRC tissues and adjacent normal tissues. Following, the methylation level of p16 exon 1/2 was negatively related to p16 protein expression. Further correlation analysis revealed that p16 exon 1 hypermethylation was associated with N/Dukes staging (p = 0.033), and p16 exon 2 hypermethylaiton was associated with T staging (p = 0.035). CONCLUSIONS: The p16 gene body was remarkably hyper-methylated in CRC tissues and associated with p16 protein expression and cancer clinicopathological staging. The combination of p16 exon 1 and exon 2 could better reflect the overall methylation status of p16 gene body and provide potential biomarkers of CRC.


Assuntos
Biomarcadores Tumorais , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Metilação de DNA , Éxons , Sequência de Bases , Cromatografia Líquida , Ilhas de CpG , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Estadiamento de Neoplasias , Regiões Promotoras Genéticas , Curva ROC , Análise de Sequência de DNA , Espectrometria de Massas em Tandem
13.
Mol Pharm ; 14(10): 3598-3608, 2017 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-28892400

RESUMO

Bioadhesive nanoparticles based on poly(vinyl methyl ether/maleic anhydride) (PVMMA) and poly(ethylene glycol) methyl ether-b-poly(d,l-lactic acid) (mPEG-b-PLA) were produced by the emulsification solvent evaporation method. Paclitaxel was utilized as the model drug, with an encapsulation efficiency of up to 90.2 ± 4.0%. The nanoparticles were uniform and spherical in shape and exhibited a sustained drug release compared with Taxol. m-NPs also exhibited favorable bioadhesive efficiency at the same time. Coumarin 6 or DiR-loaded nanoparticles with/without PVMMA (C6-m-NPs/DiR-m-NPs or C6-p-NPs/DiR-p-NPs) were used for cellular uptake and intestinal adhesion experiments, respectively. C6-m-NPs were shown to enhance cellular uptake, and caveolae/lipid raft mediated endocytosis was the primary route for the uptake of the nanoparticles. Favorable bioadhesive efficiency led to prolonged retention in the intestine reflected by the fluorescence in isolated intestines ex vivo. In a ligated intestinal loops model, C6-m-NPs showed a clear advantage for transporting NPs across the mucus layer over C6-p-NPs and free C6. The apparent permeability coefficient (Papp) of PTX-m-NPs through Caco-2/HT29 monolayers was 1.3- and 1.6-fold higher than PTX-p-NPs and Taxol, respectively, which was consistent with the AUC0-t of different PTX formulations after oral administration in rats. PTX-m-NPs also exhibited a more effective anticancer efficacy, with an IC50 of 0.2 ± 1.4 µg/mL for A549 cell lines, further demonstrating the advantage of bioadhesive nanoparticles. The bioadhesive nanoparticles m-NPs demonstrated both mucus permeation and epithelial absorption, and thus, this bioadhesive drug delivery system has the potential to improve the bioavailability of drugs that are insoluble in the gastrointestinal environment.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Portadores de Fármacos/química , Mucosa Intestinal/metabolismo , Nanopartículas/química , Paclitaxel/farmacologia , Células A549 , Administração Oral , Animais , Disponibilidade Biológica , Células CACO-2 , Cumarínicos/química , Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Células HT29 , Humanos , Masculino , Maleatos/química , Camundongos , Modelos Animais , Permeabilidade , Poliésteres/química , Polietilenoglicóis/química , Polietilenos/química , Ratos , Ratos Sprague-Dawley , Tiazóis/química
14.
Zhongguo Zhong Yao Za Zhi ; 42(13): 2510-2517, 2017 Jul.
Artigo em Zh | MEDLINE | ID: mdl-28840692

RESUMO

Twenty-eight compounds were isolated and purified from Clinopodium chinense by Sephedax LH-20, ODS, MCI and preparative HPLC. Their structures were identified as apigenin (1), apigenin-7-O-ß-D-glucopyranoside (2), apigenin-7-O-ß-D-glucuronopyranoside (3), thellungianol (4), apigenin-7-O-ß-D-rutinoside (5), luteolin (6), luteolin-4'-O-ß-D-glucopyranoside (7), apigenin-7-O-ß-D-pyranglycuronate butyl ester (8), luteolin-7-O-ß-D-rutinoside (9), luteolin-7-O-ß-D-noehesperidoside (10), acacetin (11), acacetin-7-O-ß-D-glucuronopyranoside (12), buddleoside (13), naringenin (14), pruning (15), nairutin (16), isosakuranetin (17), isosakuranin (18), didymin (19), hesperidin (20), kaempferol (21), quercetin (22), kaempferol-3-O-α-L-rahmnoside (23), p-hydroxycinnamic acid (24), caffeic acid (25), cis-3-[2-[1-(3,4-dihydroxy-phenyl)-1 -hydroxymethyl]-1,3-ben-zodioxol-5-yl]-(E)-2-propenoic acid (26), mesaconic acid (27), gentisic acid 5-O-ß-D-(6'-salicylyl)-glucopyranoside (28). Among them, compounds 7, 9-10, 12, 23, 26-28 were isolated from the Clinopodium for the first time. The protective effects of compounds 1-6, 8-17 and 19 against H2O2-induced H9c2 cardiomyocyte injury were tested, compounds 15 exhibited significantly protective effects. Compared with the cell viability of (62.12±6.18)% in the model, pruning exhibited viabilities of (84.25±7.36)% at 25.0 mg•L⁻¹, respectively, using quercetin as a positive control [cell viability of (84.55±8.26)%, 20 mg•L⁻¹].


Assuntos
Lamiaceae/química , Compostos Fitoquímicos/isolamento & purificação , Animais , Apigenina/isolamento & purificação , Linhagem Celular , Sobrevivência Celular , Miócitos Cardíacos/efeitos dos fármacos , Ratos
15.
Nutr Cancer ; 68(1): 113-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26771229

RESUMO

Omge-3 polyunsaturated fatty acids (PUFAs) exhibited significant effect in inhibiting various tumors. However, the mechanisms of its anticancer role have not been fully demonstrated. The declination of 5-methylcytosine (5 mC) was closely associated with poor prognosis of tumors. To explore whether omega-3 PUFAs influences on DNA methylation level in tumors, colorectal cancer (CRC) rat model were constructed using N-methyl phosphite nitrourea and omega-3 PUFAs were fed to part of the rats during tumor induction. The PUFAs contents in the rats of 3 experimental groups were measured using gas chromatography and 5 mC level were detected by liquid chromatography tandem mass spectrometry. The results showed that tumor incidence in omega-3 treated rats was much lower than in CRC model rats, which confirmed significant antitumor role of omega-3 PUFAs. Six PUFA members categorized to omega-3 and omega-6 families were quantified and the ratio of omega-6/omega-3 PUFAs was remarkably lower in omega-3 PUFAs treatment group than in CRC model group. 5 mC content in omega-3 PUFAs treated rats was higher than in CRC model rats, suggesting omega-3 PUFAs promoted 5 mC synthesis. Therefore, omega-3 PUFAs probably inhibited tumor growth via regulating DNA methylation process, which provided a novel anticancer mechanism of omega-3 PUFAs from epigenetic view.


Assuntos
Neoplasias Colorretais/prevenção & controle , Metilação de DNA , Ácidos Graxos Ômega-3/uso terapêutico , Animais , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-3/farmacologia , Genômica , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
16.
J Asian Nat Prod Res ; 18(1): 20-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26727712

RESUMO

Two new tetracyclic triterpenoids, together with 21 known compounds, were isolated from the barks of Melia azedarach. The structures of new compounds were elucidated by the means of HRESIMS, 1D NMR, 2D NMR, and X-ray crystallography analysis.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Melia azedarach/química , Triterpenos/isolamento & purificação , Animais , Cristalografia por Raios X , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Casca de Planta/química , Spodoptera/efeitos dos fármacos , Triterpenos/química , Triterpenos/farmacologia
17.
Breast Cancer Res ; 16(6): 470, 2014 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-25380620

RESUMO

INTRODUCTION: Aberrant expression of the embryonic stem cell marker Sox2 has been reported in breast cancer (BC). We previously identified two phenotypically distinct BC cell subsets separated based on their differential response to a Sox2 transcription activity reporter, namely the reporter-unresponsive (RU) and the more tumorigenic reporter-responsive (RR) cells. We hypothesized that Sox2, as a transcription factor, contributes to their phenotypic differences by mediating differential gene expression in these two cell subsets. METHODS: We used chromatin immunoprecipitation and a human genome-wide promoter microarray (ChIP-chip) to determine the promoter occupancies of Sox2 in the MCF7 RU and RR breast cancer cell populations. We validated our findings with conventional chromatin immunoprecipitation, quantitative reverse transcription polymerase chain reaction (qPCR), and western blotting using cell lines, and also performed qPCR using patient RU and RR samples. RESULTS: We found a largely mutually exclusive profile of gene promoters bound by Sox2 between RU and RR cells derived from MCF7 (1830 and 456 genes, respectively, with only 62 overlapping genes). Sox2 was bound to stem cell- and cancer-associated genes in RR cells. Using quantitative RT-PCR, we confirmed that 15 such genes, including PROM1 (CD133), BMI1, GPR49 (LGR5), and MUC15, were expressed significantly higher in RR cells. Using siRNA knockdown or enforced expression of Sox2, we found that Sox2 directly contributes to the higher expression of these genes in RR cells. Mucin-15, a novel Sox2 downstream target in BC, contributes to the mammosphere formation of BC cells. Parallel findings were observed in the RU and RR cells derived from patient samples. CONCLUSIONS: In conclusion, our data supports the model that the Sox2 induces differential gene expression in the two distinct cell subsets in BC, and contributes to their phenotypic differences.


Assuntos
Adenocarcinoma/genética , Neoplasias da Mama/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição SOXB1/genética , Antígeno AC133 , Adenocarcinoma/metabolismo , Antígenos CD/genética , Neoplasias da Mama/metabolismo , Imunoprecipitação da Cromatina , Feminino , Glicoproteínas/genética , Humanos , Células MCF-7 , Mucinas/genética , Peptídeos/genética , Fenótipo , Complexo Repressor Polycomb 1/genética , RNA Interferente Pequeno , Receptores Acoplados a Proteínas G/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOXB1/metabolismo
18.
Electrophoresis ; 35(24): 3479-86, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24888630

RESUMO

A new method of combining macroporous RP (mRP) protein fractionation with RPLC peptide separation MS/MS is reported for profiling the phosphoproteome of a complex sample. In this method, an mRP-C18 column was used to fractionate the proteins from a whole cell lysate of a breast cancer cell line, MDA-MB-231, into 38 fractions. Each fraction was subjected to tryptic digestion, sequential phosphopeptide enrichment by immobilized metal ion affinity chromatography and titanium dioxide (TiO2 ), followed by capillary RPLC-MS/MS analysis. For comparison, the conventional method of using strong cation exchange RPLC separation of peptides combined with MS/MS was also used for analyzing the phosphoproteome. Replicate experiments by the mRP-RPLC method identified 1585 distinct phosphoproteins with 4519 phosphopeptides, compared to 1585 phosphoproteins with 4297 phosphopeptides by strong cation exchange RPLC, with a total of 1947 phosphoproteins and 6278 phosphopeptides identified from the combined results. While the two methods have similar ability in the identification of the phosphoproteome, they produce complementary information. The phosphoproteins identified in this study, including 67 novel phosphorylation sites from 56 breast cancer related proteins, can serve as the entry point for future validation with biological implications in breast cancer. The MS proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD000948 and DOI 10.6019/PXD000948.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Cromatografia de Fase Reversa/métodos , Proteínas de Neoplasias/análise , Fosfopeptídeos/análise , Proteômica/métodos , Espectrometria de Massas em Tandem/métodos , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos
19.
BMC Cancer ; 14: 328, 2014 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-24885403

RESUMO

BACKGROUND: Sox2, a transcription factor and an embryonic stem cell marker, has been implicated in the pathogenesis of breast cancer (BC). YB-1 is another transcription factor that has been shown to promote stemness in BC cells. METHODS: Western blotting, quantitative PCR, and siRNAs were used to query the regulatory relationships between YB-1, Sox2, and their downstream targets. Chromatin immunoprecipitation was used to detect YB-1 interactions at the Sox2 promoter. Mammosphere and soft agar assays were used to assess the phenotypic consequences of YB-1 knockdown. RESULTS: Here, we report that YB-1 regulates Sox2. YB-1 was found to bind to the SOX2 promoter and down-regulate its expression in MCF7 and ZR751. The regulatory interaction between YB-1 and Sox2 was drastically different between the two phenotypically distinct cell subsets, purified based on their differential response to a Sox2 reporter. They are referred to as the reporter unresponsive (RU) cells and the reporter responsive (RR) cells. Upon siRNA knockdown of YB-1, RU cells showed an increase in Sox2 expression but no change in Sox2 reporter activity; in contrast, RR cells exhibited increased expression and reporter activity of Sox2. Correlating with these findings, YB-1 knockdown induced a differential response in the expression of genes known to be regulated by both Sox2 and YB-1 (e.g. CCND1 and ITGA6). For instance, in response to YB-1 knockdown, CCND1 and ITGA6 expression were decreased or unchanged in RU cells but paradoxically increased in RR cells. Compared to RU cells, RR cells were significantly more resistant to the suppression of mammosphere formation due to YB-1 knockdown. Importantly, mammospheres derived from parental MCF7 cells treated with YB-1 siRNA knockdown exhibited higher expression levels of SOX2 and its downstream targets. CONCLUSIONS: To conclude, in a subset of BC cells, namely RR cells, YB-1 regulates Sox2 to coordinately maintain stemness and tumorigenic properties.


Assuntos
Neoplasias da Mama/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo , Sítios de Ligação , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Ciclina D1/genética , Ciclina D1/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Integrina alfa6/genética , Integrina alfa6/metabolismo , Células MCF-7 , Proteína Homeobox Nanog , Células-Tronco Neoplásicas/patologia , Fenótipo , Regiões Promotoras Genéticas , Interferência de RNA , Fatores de Transcrição SOXB1/genética , Transfecção , Proteína 1 de Ligação a Y-Box/genética
20.
Biomed Chromatogr ; 28(5): 673-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24338899

RESUMO

In this paper, a sensitive, rapid and reproducible high-performance liquid chromatography-tandem mass spectrometry method was developed to analyze 16α-hydro-ent-kauran-17,19-dioic acid in rat plasma. First, this study compared the pharmacokinetics of 16α-hydro-ent-kauran-17,19-dioic acid after oral administration of monomer and Siegesbeckiae pubescens Makino extract in rat plasma with approximately the same dosage of 6.0 mg/kg. Second, chromatographic separation was performed on a Waters Symmetry C18 column (2.1 × 100 mm, 3.5 µm) with isocratic elution using methanol-water containing 5 mmol/L ammonium acetate (70:30, v/v) as mobile phase at a flow rate of 0.2 mL/min. The calibration curves were linear over the range of 30-12000 ng/mL for monomer. At different time points (0, 0.083, 0.25, 0.75, 1, 2, 4, 6, 8, 12, 18, 24, 36, 48, 60 and 72 h) after administration, the concentrations of monomer in rat plasma were determined and main pharmacokinetic parameters were estimated. The double absorption presented in this study indicates that the pharmacokinetics of monomer in rat plasma have significant differences between different groups.


Assuntos
Asteraceae/química , Cromatografia Líquida de Alta Pressão/métodos , Diterpenos do Tipo Caurano/farmacocinética , Extratos Vegetais/farmacocinética , Espectrometria de Massas em Tandem/métodos , Administração Oral , Animais , Diterpenos do Tipo Caurano/administração & dosagem , Diterpenos do Tipo Caurano/sangue , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/sangue , Ratos , Ratos Sprague-Dawley
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