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1.
Metab Brain Dis ; 34(1): 141-152, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30302719

RESUMO

Gliomas represent the most common primary malignant brain tumors in adults, with an extremely poor prognosis. Among several risk factors, lifestyle was also recently identified as a major risk factor for the development of primary glioma. In the present study, we explore the relationship between obesity and glioma in a cellular model. Thus, we have study the influence of adipocytes secretome on glioma cell line GL261. Using the 3T3-L1 adipocyte cell line, and its conditioned medium (adipokines-enriched medium), we showed that adipocyte-released factors relate with glioma angiogenic, growth, hormones and metabolic behavior by MALDI-TOF-MS and proteomic array analysis. In a first view, STI1, hnRNPs and PGK1 are under expressed on CGl. Similarly, both carbonic anhydrase and aldose reductase are even suppressed in glioma cells that grown under adipokines-enriched environment. Contrariwise, RFC1, KIF5C, ANXA2, N-RAP and RACK1 are overexpressed in GL261 cell the in the presence of the adipokines-enriched medium. We further identified the factors that are released by adipocyte cells, and revealed that several pro-inflammatory and angiogenic factors, such as IL-6, IL-11, LIF, PAI-1, TNF-α, endocan, HGF, VEGF IGF-I, were secreted to the medium into a high extent, whereas TIMP-1 and SerpinE1 were under expressed on CGl. This study discloses an interesting in vitro model for the study of glioma biology under a "obesity" environment, that can be explored for the understanding of cancer cells biology, for the search of biomarkers, prognostic markers and therapeutic approaches.


Assuntos
Adipócitos/metabolismo , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Inflamação/metabolismo , Células 3T3-L1 , Animais , Neoplasias Encefálicas/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Glioma/patologia , Camundongos , Proteoma , Proteômica
2.
Steroids ; 78(12-13): 1226-32, 2013 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-24036418

RESUMO

This work presents a novel database search engine - MLibrary - designed to assist the user in the detection and identification of androgenic anabolic steroids (AAS) and its metabolites by matrix assisted laser desorption/ionization (MALDI) and mass spectrometry-based strategies. The detection of the AAS in the samples was accomplished by searching (i) the mass spectrometric (MS) spectra against the library developed to identify possible positives and (ii) by comparison of the tandem mass spectrometric (MS/MS) spectra produced after fragmentation of the possible positives with a complete set of spectra that have previously been assigned to the software. The urinary screening for anabolic agents plays a major role in anti-doping laboratories as they represent the most abused drug class in sports. With the help of the MLibrary software application, the use of MALDI techniques for doping control is simplified and the time for evaluation and interpretation of the results is reduced. To do so, the search engine takes as input several MALDI-TOF-MS and MALDI-TOF-MS/MS spectra. It aids the researcher in an automatic mode by identifying possible positives in a single MS analysis and then confirming their presence in tandem MS analysis by comparing the experimental tandem mass spectrometric data with the database. Furthermore, the search engine can, potentially, be further expanded to other compounds in addition to AASs. The applicability of the MLibrary tool is shown through the analysis of spiked urine samples.


Assuntos
Substâncias para Melhoria do Desempenho/urina , Ferramenta de Busca , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/normas , Esteroides/urina , Adulto , Dopagem Esportivo , Feminino , Humanos , Masculino , Padrões de Referência , Software , Espectrometria de Massas em Tandem/normas , Adulto Jovem
3.
Anal Bioanal Chem ; 399(2): 861-75, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21049269

RESUMO

A comparison between ultrasonication and microwave irradiation as tools to achieve a rapid sample treatment for the analysis of banned doping substances in human urine by means of gas chromatography-mass spectrometry (GC-MS) was performed. The following variables were studied and optimised: (i) time of treatment, (ii) temperature, (iii) microwave power and (iv) ultrasonic amplitude. The results were evaluated and compared with those achieved by the routine method used in the World Anti-Doping Agency (WADA) accredited Antidoping Laboratory of Rome. Only under the effect of the ultrasonic field was it possible to enhance the enzymatic hydrolysis reaction rate of conjugated compounds. Similar reaction yield to the routine method was achieved after 10 min for most compounds. Under microwave irradiation, denaturation of the enzyme occurs for high microwave power. The use of both ultrasonic or microwave energy to improve the reaction rate of the derivatisation of the target compounds with trimethyliodosilane/methyl-N-trimethylsilyltrifluoroacetamide (TMSI/MSTFA/NH(4)I/2-mercaptoethanol) was also evaluated. To test the use of the two systems in the acceleration of the reaction with TMSI, a pool of 55 banned substances and/or their metabolites were used. After 3 min of ultrasonication, 34 of the 55 compounds had recoveries similar to those obtained with the classic procedure that lasts for 30 min (Student's t test, n = 5), 18 increased to higher silylation yields, and for the compounds 13ß,17α-diethyl-3α,17ß-dihydroxy-5α-gonane (norboletone metabolite 1), metoprolol and metipranolol the same results were obtained increasing the ultrasonication time to 5 min. Similar results were obtained after 3 min of microwave irradiation at 1,200 W. In this case, 30 of the 55 compounds had recoveries similar to the classic procedure (Student's t test, n = 5) whilst 18 had higher silylation yields. For the compounds 3α-hydroxy-1α-methyl-5α-androstan-17-one (mesterolone metabolite 1), 17α-ethyl-5ß-estrane-3α,17ß,21-triol (norethandrolone metabolite 1), epioxandrolone, 4-chloro-6ß,17ß-dihydroxy-17α-methyl-1,4-androstadien-3-one (chlormetandienone metabolite 1), carphedon, esmolol and bambuterol the same results were obtained after 5 min under microwave irradiation.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Micro-Ondas , Detecção do Abuso de Substâncias/métodos , Ultrassom , Urinálise/métodos , Humanos
4.
Rapid Commun Mass Spectrom ; 24(16): 2375-85, 2010 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-20635322

RESUMO

A rapid sample treatment procedure for the gas chromatography/mass spectrometry (GC/MS) determination of anabolic steroids in human urine has been developed. The new procedure makes use of ultrasonic energy to reduce reaction times and increase the overall sensitivity. The following variables affecting the performance of the ultrasonic treatment were optimised: (i) time, (ii) device, (iii) frequency, and (iv) temperature. It was found that, under an ultrasonic field, the hydrolysis of conjugated steroids with beta-glucuronidase from Escherichia coli K12 was possible with a treatment time of 10 min. The accuracy and precision of the ultrasonic method were found to be in agreement with those achieved with the conventional thermal conductivity procedure (Student's t-test; p = 0.05, n = 10). After the enzymatic hydrolysis, the derivatisation of the target compounds with trimethylsilyl (TMS) reagent, methyl-N-trimethylsilyltrifluoroacetamide (MSTFA)/NH(4)I/dithioerythritol (DTE) (1000:2:4, v/w/w), was also accelerated using ultrasonic energy. In order to test the applicability of the use of ultrasonic energy in the acceleration of the derivatisation reaction with TMS, the classic method of thermal conductivity was applied for comparative purposes to a pool of 35 androgenic anabolic steroids (AAS) and/or their metabolites. The results demonstrated that after 3 min of sonication in a Sonoreactor device (50% amplitude), 19 of the 35 compounds studied showed similar reaction yield to those obtained with the classic procedure requiring 30 min (Student's t-test; p = 0.05, n = 5); 13 increased to higher silylation yields; and for the steroids 1-testosterone, danazol and etiocholanolone-D5, the same results were obtained using a sonication time of 5 min.The overall applicability of the ultrasonic-based sample treatment method is shown by the analysis of five urine samples. The results are similar to those achieved by the routine procedure. The new method is fast, robust, and allows high sample throughput.


Assuntos
Anabolizantes/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Humanos , Detecção do Abuso de Substâncias/instrumentação , Ultrassom
5.
Anal Chim Acta ; 650(2): 151-9, 2009 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-19720186

RESUMO

Recent tools addressed to accelerate the different steps of the sample treatment for protein identification in modern workflows are reviewed and critically commented in this manuscript. Heating, microspin columns, ultrasonic energy, high pressure, infrared energy, microwave energy, alternating electric fields and microreactors are outlined as useful tools that can be used to accelerate all or some of the following steps for in-gel or in-liquid based approaches for protein identification: (i) protein dissolution/denaturation, (ii) protein reduction, (iii) protein alkylation and (iv) protein digestion. The advantages and drawbacks, along with the main differences among the different tools are also commented. Future prospects for hyphenation of methods are also discussed. Researchers are informed also in this work regarding the main problems to be found when implementing any of the above mentioned methods.


Assuntos
Enzimas/metabolismo , Espectrometria de Massas/métodos , Proteínas/análise , Desnaturação Proteica , Processamento de Proteína Pós-Traducional , Proteínas/química , Proteômica
6.
Rapid Commun Mass Spectrom ; 23(12): 1783-91, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19444857

RESUMO

New data on sample preparation and matrix selection for the fast screening of androgenic anabolic steroids (AAS) by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) is presented. The rapid screening of 15 steroids included in the World Anti-Doping Agency (WADA) prohibited list using MALDI was evaluated. Nine organic and two inorganic matrices were assessed in order to determine the best matrix for steroid identification in terms of ionisation yield and interference by characteristic matrix ions. The best results were achieved for the organic matrices 2-(4-hydroxyphenylazo)benzoic acid (HABA) and trans-3-indoleacrylic acid (IAA). Good signals for all the steroids studied were obtained for concentrations as low as 0.010 and 0.050 microg/mL on the MALDI sample plate for the HABA and IAA matrices, respectively. For these two matrices, the sensitivity achieved by MALDI is comparable with the sensitivity achieved by gas chromatography/mass spectrometry (GC/MS), which is the conventional technique used for AAS detection. Furthermore, the accuracy and precision obtained with MALDI are very good, since an internal mass calibration is performed with the matrix ions. For the inorganic matrices, laser fluences higher than those used with organic matrices are required to obtain good MALDI signals. When inorganic matrices were used in combination with glycerol as a dispersing agent, an important reduction of the background noise was observed. Urine samples spiked with the study compounds were processed by solid-phase extraction (SPE) and the screening was consistently positive.


Assuntos
Anabolizantes/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Esteroides/química , Humanos , Masculino , Peso Molecular , Sensibilidade e Especificidade , Urina/química , Adulto Jovem
7.
J Proteome Res ; 7(5): 2097-106, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18410137

RESUMO

The influence of the protein staining used to visualize protein bands, after in-gel protein separation, for the correct identification of proteins by peptide mass fingerprint (PMF) after application of the ultrasonic in-gel protein protocol was studied. Coomassie brilliant blue and silver nitrate, both visible stains, and the fluorescent dyes Sypro Red and Sypro Orange were evaluated. Results obtained after comparison with the overnight in-gel protocol showed that good results, in terms of protein sequence coverage and number of peptides matched, can be obtained with anyone of the four stains studied. Two minutes of enzymatic digestion time was enough for proteins stained with coomassie blue, while 4 min was necessary when silver or Sypro stainings were employed in order to reach equivalent results to those obtained for the overnigh in-gel protein protocol. For the silver nitrate stain, the concentration of silver present in the staining solution must be 0.09% (w/v) to minimize background in the MALDI mass spectra.


Assuntos
Espectrometria de Massas/métodos , Mapeamento de Peptídeos , Proteínas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Coloração e Rotulagem , Ultrassom , Animais , Bovinos , Corantes/química , Eletroforese em Gel de Poliacrilamida , Proteínas/análise , Proteínas/química , Soroalbumina Bovina/análise
8.
Talanta ; 72(3): 968-75, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19071711

RESUMO

Two advanced oxidation processes (AOPs), based on high-intensity focused ultrasound (HIFU), namely, KMnO(4)/HCl/HIFU and H(2)O(2)/HCl/HIFU are studied and compared for the determination of toxic arsenic in human urine [As(III)+As(V)+MMA+DMA] by flow-injection hydride-generation atomic absorption spectrometry (FI-HG-AAS). The KMnO(4)/HCl/HIFU procedure was found to be adequate for organic matter degradation in human urine. l-cysteine (letra minuscula) was used for As reduction to the trivalent state. The new procedure was assessed with seven urines certified in different As species. Results revealed that with KMnO(4)/HCl/HIFU plus l-cysteine the toxic arsenic can be accurately measured in human urine whilst the H(2)O(2)/HCl/HIFU procedure underestimates toxic As. DMA and MMA degradation in urine were observed, due to the effects of the ultrasonic field. Recoveries for As(III), As(V), MMA and DMA were within the certified ranges. Arsenobetaine was not degraded by the AOPs. The new procedure adheres well to the principles of analytical minimalism: (i) low reagent consumption, (ii) low reagent concentration, (iii) low waste production and (iv) low amount of time required for sample preparation and analysis.

9.
Talanta ; 68(3): 813-8, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18970395

RESUMO

Due to new findings, the methodology based on room-temperature ultrasonic irradiation (sonolysis) for conversion of organomercurials into inorganic mercury [J.L. Capelo, I. Lavilla, C. Bendicho, Anal. Chem. 72 (2000) 4979-4984.] is further investigated. Inorganic mercury is selectively determined by Flow Injection-Cold Vapour Atomic Absorption Spectrometry (FI-CV-AAS) using SnCl(2)/HCl. Complete oxidation of methyl-mercury can be accomplished within 90 s whilst phenyl and diphenyl-mercury can be degraded within 10s using a 50% sonication amplitude (100 W nominal power) provided by a probe ultrasonic device (20.5 kHz frequency) and a 1 mol L(-1) HCl liquid medium with the presence of hypochlorite ion. The importance of hypochlorite in reduction of organomercurials by stannous chloride is highlighted. Oxidation kinetics indicated a pseudo first-order reaction for methyl-mercury, phenyl-mercury, and diphenyl-mercury.

10.
Talanta ; 68(4): 1156-61, 2006 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18970445

RESUMO

Three different ultrasonic-based sample treatment approaches, the automated ultrasonic slurry sampling, the ultrasonic assisted acid solid-liquid extraction (ASLE) and the enzymatic probe sonication (EPS) were compared and discussed for the determination of Cd and Pb by ET-AAS in biological reference materials. The sample mass chosen to perform the analysis was 10mg and the liquid volume was 1ml of nitric acid 1M. The best results were obtained with the slurry procedure with which it was possible accurate and precise determination of the Cd and Pb content in four of the five reference materials studied. Optimum performance (total metal extraction) of ASLE assisted by ultrasound for Cd was only achieved in two of the four materials assessed whereas total Pb recovery was only possible in three of the five samples. Total extraction with the enzymatic probe sonication was only obtained for Cd in oyster tissue. Neither ASLE nor EPS were able to extract Cd or Pb from spruce needles. Pb concentration obtained after EPS was found to be highly dependent from sample centrifugation speed and time.

11.
Talanta ; 66(5): 1272-80, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18970118

RESUMO

Analytical minimalism is a concept that deals with the optimization of all stages of an analytical procedure so that it becomes less time, cost, sample, reagent and energy consuming. The guide-lines provided in the USEPA extraction method 3550B recommend the use of focused ultrasound (FU), i.e., probe sonication, for the solid-liquid extraction of Polycyclic Aromatic Hydrocarbons, PAHs, but ignore the principle of analytical minimalism. The problems related with the dead sonication zones, often present when high volumes are sonicated with probe, are also not addressed. In this work, we demonstrate that successful extraction and quantification of PAHs from sediments can be done with low sample mass (0.125g), low reagent volume (4ml), short sonication time (3min) and low sonication amplitude (40%). Two variables are here particularly taken into account for total extraction: (i) the design of the extraction vessel and (ii) the solvent used to carry out the extraction. Results showed PAHs recoveries (EPA priority list) ranged between 77 and 101%, accounting for more than 95% for most of the PAHs here studied, as compared with the values obtained after soxhlet extraction. Taking into account the results reported in this work we recommend a revision of the EPA guidelines for PAHs extraction from solid matrices with focused ultrasound, so that these match the analytical minimalism concept.

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