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1.
Transl Psychiatry ; 12(1): 114, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35318322

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disease featuring social interaction deficits and repetitive/stereotyped behaviours; the prevalence of this disorder has continuously increased. Progranulin (PGRN) is a neurotrophic factor that promotes neuronal survival and differentiation. However, there have not been sufficient studies investigating its effect in animal models of autism. This study investigated the effects of PGRN on autistic phenotypes in rats treated with valproic acid (VPA) and assessed the underlying molecular mechanisms. PGRN was significantly downregulated in the cerebellum at postnatal day 14 (PND14) and PND35 in VPA-exposed rats, which simultaneously showed defective social preference, increased repetitive behaviours, and uncoordinated movements. When human recombinant PGRN (r-PGRN) was injected into the cerebellum of newborn ASD model rats (PND10 and PND17), some of the behavioural defects were alleviated. r-PGRN supplementation also reduced cerebellar neuronal apoptosis and rescued synapse formation in ASD rats. Mechanistically, we confirmed that PGRN protects neurodevelopment via the PI3K/Akt/GSK-3ß pathway in the cerebellum of a rat ASD model. Moreover, we found that prosaposin (PSAP) promoted the internalisation and neurotrophic activity of PGRN. These results experimentally demonstrate the therapeutic effects of PGRN on a rat model of ASD for the first time and provide a novel therapeutic strategy for autism.


Assuntos
Transtorno do Espectro Autista , Ácido Valproico , Animais , Transtorno do Espectro Autista/induzido quimicamente , Transtorno do Espectro Autista/tratamento farmacológico , Cerebelo , Glicogênio Sintase Quinase 3 beta , Fosfatidilinositol 3-Quinases , Progranulinas/uso terapêutico , Proteínas Proto-Oncogênicas c-akt , Ratos , Ácido Valproico/efeitos adversos
2.
Nanoscale ; 11(13): 6089-6100, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30869726

RESUMO

Nanoscale metal-organic frameworks (NMOFs) with ultrahigh porosities and incredibly high internal surface areas are potential nanomaterials to fabricate multifunctional theranostic platforms. This work describes the design of Raman tag-bridged core-shell nanoparticles (NPs) for multifunctional Raman imaging and chemo-phototherapy. Au@Cu3(BTC)2 NPs are characterized with the core of gold nanoparticles (Au NPs), the bridging of the Raman reporter molecule 4-mercaptobenzoic acid (4-MBA), and the shell of copper(ii) carboxylate MOFs (Cu3(BTC)2). The preparation strategy is based on the assembly of Cu3(BTC)2 on Au NPs with the help of bifunctional 4-MBA. The Raman reporter molecule 4-MBA with characteristic Raman signals is involved in the linking of Au NPs and Cu3(BTC)2, avoiding additional modification of Raman reporter molecules and thus simplifying the synthesis process. Aptamers and the anti-cancer drug doxorubicin (DOX) were modified on Au@Cu3(BTC)2 for functionalization. The Au NP core not only acted as photothermal agents to produce hyperthermia for destroying cancer cells and promoting drug release, but also served as surface enhanced Raman scattering (SERS) substrates to enhance the Raman signal of 4-MBA. The Cu3(BTC)2 shell can provide sites for aptamer functionalization and drug loading. The Au@Cu3(BTC)2 NPs exhibited high drug loading capacity (57%) and good photothermal conversion efficiency. With good biocompatibility, high drug loading capacity, excellent SERS effect and photothermal effect, Au@Cu3(BTC)2 NPs showed effective theranostic applications in cell tracking and in vivo synergistic chemo-photothermal therapy of tumors, demonstrating the feasibility of theranostic applications in cancer diagnosis and therapy. It is speculated that this work would inspire further studies on the construction of theranostic nanoplatforms.


Assuntos
Materiais Biocompatíveis/química , Cobre/química , Portadores de Fármacos/química , Ouro/química , Nanopartículas Metálicas/química , Animais , Aptâmeros de Nucleotídeos/química , Benzoatos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Humanos , Lasers , Estruturas Metalorgânicas/química , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/terapia , Fototerapia , Análise Espectral Raman , Compostos de Sulfidrila/química
3.
Anal Chem ; 87(1): 406-12, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25435245

RESUMO

The present study reported on an in situ solvothermal growth method for immobilization of metal-organic framework MOF-5 on porous copper foam support for enrichment of plant volatile sulfides. The porous copper support impregnated with mother liquor of MOF-5 anchors the nucleation and growth of MOF crystallites at its surface, and its architecture of the three-dimensional channel enables accommodation of the MOF-5 crystallite seed. A continuous and well-intergrown MOF-5 layer, evidenced from scanning electron microscope imaging and X-ray diffraction, was successfully immobilized on the porous metal bar with good adhesion and high stability. Results show that the resultant MOF-5 coating was thermally stable up to 420 °C and robust enough for replicate extraction for at least 200 times. The MOF-5 bar was then applied to the headspace sorptive extraction of the volatile organic sulfur compounds in Chinese chive and garlic sprout in combination with thermal desorption-gas chromatography/mass spectrometry. It showed high extraction sensitivity and good selectivity to these plant volatile sulfides owing to the extraordinary porosity of the metal-organic framework as well as the interaction between the S-donor sites and the surface cations at the crystal edges. Several primary sulfur volatiles containing allyl methyl sulfide, dimethyl disulfide, diallyl sulfide, methyl allyl disulfide, and diallyl disulfide were quantified. Their limits of detection were found to be in the range of 0.2-1.7 µg/L. The organic sulfides were detected in the range of 6.0-23.8 µg/g with recoveries of 76.6-100.2% in Chinese chive and 11.4-54.6 µg/g with recoveries of 77.1-99.8% in garlic sprout. The results indicate the immobilization of MOF-5 on copper foam provides an efficient enrichment formats for noninvasive sampling of plant volatiles.


Assuntos
Allium/química , Compostos Alílicos/análise , Cobre/química , Alho/química , Compostos Organometálicos/química , Sulfetos/análise , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas , Porosidade , Difração de Raios X
4.
J Chromatogr A ; 1316: 29-36, 2013 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-24120024

RESUMO

We have developed a novel ultrasensitive online analytical system which integrated solid-phase-based extraction (SPBE) techniques with ultra-high performance liquid chromatography (UPLC) based on a fractionized sampling and stacking (FSS) strategy. FSS was proposed as a novel peak compression strategy to prevent band broadening and distortion caused by excessive solvents with high elution strength, which has been a main obstacle to conjunction of sample preparation techniques with UPLC. Such a strategy was based on online dividing a sample solution into fractions by plugs of weak mobile phase, followed by head-column stacking process, aiming to obtain a quite sharp sample zone. FSS enables UPLC to tolerate much larger injection volume of solvents with high elution strength, which facilitates hyphenation of SPBE with UPLC without peak distortion or loss of sensitivity. On the basis above, an online SPBE-UPLC system was realized by FSS, and its applicability was preliminarily verified by the successful development of a sensitive solid phase extraction-FSS-UPLC method for the determination of triazines. Subsequently an integrated online system incorporating molecularly imprinted in-tube solid phase microextraction, derivatization and FSS-UPLC was developed for the analysis of ultra trace 24-epibrassinolide. The developed method was ultrasensitive with detection limit as low as 0.7 ng/L, and the linear range of the method was 3-5000 ng/L. The endogenous 24-epibrassinolide in pollen, flower and seed samples was determined, which showed satisfactory recoveries in the range of 81.2-116% and good precision with relative standard deviation (RSD) values between 4.7 and 9.7%. This online analytical method was sensitive, reliable, rapid and applicable to trace analysis in complex samples.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Brassinosteroides/análise , Brassinosteroides/isolamento & purificação , Flores/química , Limite de Detecção , Modelos Lineares , Modelos Químicos , Pólen/química , Reprodutibilidade dos Testes , Sementes/química , Esteroides Heterocíclicos/análise , Esteroides Heterocíclicos/isolamento & purificação , Verduras/química
5.
J Chromatogr A ; 1262: 49-55, 2012 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-22999204

RESUMO

A novel and simple in-mold coating strategy was proposed for the preparation of uniform solid-phase microextraction (SPME) coatings. Such a strategy is based on the direct synthesis of the polymer coating on the surface of a solid fiber using a glass capillary as the mold. The capillary was removed and the polymer with well-controlled thickness could be coated on the silica fiber reproductively. Following the strategy, a new poly(acrylamide-co-ethylene glycol dimethacrylate) (poly(AM-co-EGDMA)) coating was prepared for the preconcentration of 24-epibrassinolide (24-epiBL) from plant matrix. The coating had the enrichment factor of 32 folds, and the extraction efficiency per unit thickness was 5 times higher than that of the commercial polydimethylsiloxane/divinylbenzene (PDMS/DVB) coating. A novel method based on SPME coupled with derivatization and large volume injection-high performance liquid chromatography (LVI-HPLC) was developed for the analysis of 24-epiBL. The linear range was 0.500-20.0 µg/L with the detection limit of 0.13 µg/L. The amounts of endogenous 24-epiBL in rape and sunflower breaking-wall pollens samples were determined with satisfactory recovery (77.8-104%) and reproducibility (3.9-7.9%). The SPME-DE/LVI-HPLC method is rapid, reliable, convenient and applicable for complicated plant samples.


Assuntos
Brassinosteroides/análise , Pólen/química , Microextração em Fase Sólida/instrumentação , Esteroides Heterocíclicos/análise , Biotecnologia/instrumentação , Biotecnologia/métodos , Brassica rapa/química , Brassinosteroides/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Helianthus/química , Limite de Detecção , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Reprodutibilidade dos Testes , Microextração em Fase Sólida/métodos , Esteroides Heterocíclicos/isolamento & purificação
6.
Anal Bioanal Chem ; 399(10): 3367-74, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20953778

RESUMO

A novel sample preparation method for auxin analysis in plant samples was developed by vacuum microwave-assisted extraction (VMAE) followed by molecularly imprinted clean-up procedure. The method was based on two steps. In the first one, conventional solvent extraction was replaced by VMAE for extraction of auxins from plant tissues. This step provided efficient extraction of 3-indole acetic acid (IAA) from plant with dramatically decreased extraction time, furthermore prevented auxins from degradation by creating a reduced oxygen environment under vacuum condition. In the second step, the raw extract of VMAE was further subjected to a clean-up procedure by magnetic molecularly imprinted polymer (MIP) beads. Owing to the high molecular recognition ability of the magnetic MIP beads for IAA and 3-indole-butyric acid (IBA), the two target auxins in plants can be selectively enriched and the interfering substance can be eliminated by dealing with a magnetic separation procedure. Both the VMAE and the molecularly imprinted clean-up conditions were investigated. The proposed sample preparation method was coupled with high-performance liquid chromatogram and fluorescence detection for determination of IAA and IBA in peas and rice. The detection limits obtained for IAA and IBA were 0.47 and 1.6 ng/mL and the relative standard deviation were 2.3% and 2.1%, respectively. The IAA contents in pea seeds, pea embryo, pea roots and rice seeds were determined. The recoveries were ranged from 70.0% to 85.6%. The proposed method was also applied to investigate the developmental profiles of IAA concentration in pea seeds and rice seeds during seed germination.


Assuntos
Fracionamento Químico/métodos , Ácidos Indolacéticos/isolamento & purificação , Impressão Molecular/métodos , Oryza/química , Pisum sativum/química , Extratos Vegetais/isolamento & purificação , Fracionamento Químico/instrumentação , Cromatografia Líquida de Alta Pressão , Ácidos Indolacéticos/análise , Micro-Ondas , Impressão Molecular/instrumentação , Extratos Vegetais/análise , Polímeros/química , Sementes/química
7.
J Chromatogr A ; 1217(42): 6455-61, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20846659

RESUMO

In the study, a kind of novel styrene-co-4-vinylpyridine (St-co-4-VP) porous magnetic polymer beads was prepared by microwave irradiation using suspension polymerization. Microwave heating preparation greatly reduced the polymerization time to 1h. Physical characteristic tests suggested that these beads were cross-linking and possessed spherical shape, good magnetic response and porous morphologies with a narrow diameter distribution of 70-180 µm. Therefore, these beads displayed the long-term stability after undergoing 100-time extractions. Then, an analytical method for the determination of trace 24-epiBR in plant samples was developed by magnetic polymer bead extraction coupled with high performance liquid chromatography-fluorescence detection. St-co-4-VP magnetic polymer beads demonstrated the higher extraction selectivity for 24-epiBR than other reference compounds. Linear range was 10.00-100.0 µg/L with a relative standard deviation (RSD) of 6.7%, and the detection limit was 6.5 µg/kg. This analytical method was successfully applied to analyze the trace 24-epiBR in cole and breaking-wall rape pollen samples with recoveries of 77.2-90.0% and 72.3-83.4%, respectively, and RSDs were less than 4.1%. The amount of 24-epiBR in real breaking-wall rape pollen samples was found to be 26.2 µg/kg finally. This work proposed a sensitive, rapid, reliable and convenient analytical method for the determination of trace brassinosteroids in complicated plant samples by the use of St-co-4-VP magnetic polymer bead extraction coupled with chromatographic method.


Assuntos
Colestanóis/análise , Cromatografia Líquida de Alta Pressão/métodos , Microesferas , Pólen/química , Poliestirenos/química , Polivinil/química , Piridinas/química , Esteroides Heterocíclicos/análise , Brassinosteroides , Campos Eletromagnéticos , Modelos Lineares , Micro-Ondas , Plantas/química , Polimerização , Sensibilidade e Especificidade
8.
J AOAC Int ; 93(3): 849-54, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20629386

RESUMO

A sensitive and accurate method consisting of microwave-assisted extraction (MAE) coupled with single drop microextraction (SDME) and HPLC was developed for the determination of four trace estrogen adulterants, including estriol (E3), estradiol (E2), ethinyl estradiol (EE), and estrone (E1), in different soybean dietary supplements. The samples were extracted by MAE; the extracts were cleaned up and enriched by SDME, and then analyzed by HPLC. The conditions of MAE were optimized, and the effects of solvent and extraction time in SDME on the enrichment capacity were studied. The enrichment factors of E3, E2, EE, and E1 under the optimized conditions were 247-, 335-, 316-, and 319-fold, respectively. The linear range of the MAE-SDME-HPLC method ranged from 5.0 to 180.0 microg/L, and the detection limit from 1.1 to 1.2 microg/L. The RSD ranged from 7.9 to 9.6%. Three soybean dietary supplements, including oral liquid, capsule, and tablet forms, were analyzed. The spike recovery was more than 70%, with RSD lower than 13.2%. It was shown that the proposed method was accurate, sensitive, and suitable for the determination of trace analytes in complex samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Contaminação de Medicamentos , Estrogênios/análise , Glycine max/química , Isoflavonas/análise , Micro-Ondas
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