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1.
Biomedicines ; 12(4)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38672170

RESUMO

BACKGROUND: Delay in diagnosis and therapy in patients with arthritis commonly leads to progressive articular damage. The study aimed to investigate the immunohistochemical reactivity of synovial cytokines associated with inflammation and the bone erosives/neoformatives processes among individuals diagnosed with psoriatic arthritis (PsA), rheumatoid arthritis (RA), osteoarthritis (OA), and radiographic axial spondyloarthritis (r-axSpA), with the intention of identifying potential biomarkers. METHODS: Specimens were collected from the inflamed knee joints of patients referred for arthroscopic procedures, and the synovial tissue (ST) was prepared for quantifying protein expression through immunohistochemical analysis (% expressed in Ratio_Area-Intensity) for TGF-ß1, IL-17A, Dkk1, BMP2, BMP4, and Wnt5b. The collected data underwent thorough analysis and examination of their predictive capabilities utilising receiver operating characteristic (ROC) curves. RESULTS: Valid synovial tissue samples were acquired from 40 patients for IHC quantification analysis. Initially, these patients had not undergone treatment with biologics. However, after 5 years, 4 out of 13 patients diagnosed with PsA and two out of nine patients diagnosed with RA had commenced biologic treatments. Individuals with early PsA who received subsequent biologic treatment exhibited significantly elevated IHC reactivity in ST for TGF-ß1 (p = 0.015). Additionally, patients with both PsA and RA who underwent biologic therapy displayed increased IHC reactivity for IL-17A (p = 0.016), TGF-ß1 (p = 0.009), and Dkk1 (p = 0.042). ROC curve analysis of IHC reactivity for TGF-ß1, Dkk1, and IL-17A in the synovial seems to predict future treatment with biologics in the next 5 years with the area under the curve (AUC) of a combined sum of the three values: AUC: 0.828 (95% CI: 0.689-0.968; p 0.005) S 75% E 84.4%. CONCLUSIONS: Higher synovial immunohistochemistry reactivity of IL-17A, Dkk1, and TGF-ß1 in patients with early psoriatic arthritis and rheumatoid arthritis may serve as potential indicators for predicting the necessity of utilising biologic treatments.

2.
Anal Bioanal Chem ; 414(9): 3137-3151, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35233696

RESUMO

This work describes the development of an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for the determination of 23 primary aromatic amines (PAAs) that can potentially migrate from food contact materials. The chromatographic separation was performed in a pentafluorophenylpropyl (PFPP) column achieving the separation of all PAAs in less than 6.5 min using water to acetonitrile (0.1% acetic acid in both solvents) as mobile phase and a gradient elution. The feasibility of atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) was evaluated as alternative to electrospray ionization (ESI) for the analysis of PAAs. Results showed that for most of the compounds, better responses were obtained with APCI, which shows the advantage of being less susceptible to matrix effects. Tandem mass spectrometry (MS/MS) fragmentation studies of [M + H]+ allowed for the selection of the two most characteristic and abundant product ions of the 23 PAAs which led to the development of a selective and sensitive UHPLC-APCI-MS/MS method with limits of detection ranging from 0.2 to 2 µg kg-1. Moreover, intra-day and inter-day precisions of the method in terms of relative standard deviation (RSD%) were lower than 10% and 15%, while trueness as relative error was <15% for most of the compounds. The UHPLC-APCI-MS/MS method was applied to the analysis of twenty black Nylon kitchenware samples that were submitted to migration tests using food simulant B (3% acetic acid, w/v), and the presence of PAAs were detected in eighteen samples at concentrations above the legislated limit (2 µg kg-1 of food or food simulants).


Assuntos
Pressão Atmosférica , Espectrometria de Massas em Tandem , Aminas/análise , Cromatografia Líquida de Alta Pressão/métodos , Nylons , Espectrometria de Massas em Tandem/métodos
3.
Anal Bioanal Chem ; 411(28): 7357-7373, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31659376

RESUMO

The establishment of fragmentation pathways has a great interest in the identification of new or unknown related compounds present in complex samples. On that way, tentative fragmentation pathways for the ions generated by atmospheric pressure ionization of neutral per- and polyfluorinated alkyl substances (PFASs) have been proposed in this work. Electrospray (ESI), atmospheric pressure chemical ionization (APCI) and photoionization (APPI) were evaluated using mobile phases and source conditions that enhance the ionization efficiency of ions generated. A hybrid mass spectrometer consisting of a linear ion trap and an Orbitrap was used to combine the information of both multiple-stage mass spectrometry (MSn) and mass accuracy measurements to characterize and establish the genealogical relationship between the product ions observed. The ionization mechanisms to generate ions such as [M-H]-, [M]-•, and [M+O2]-• or the in-source collision-induced dissociation (CID) fragment ions in each API source are discussed in this study. In general, fluorotelomer olefins (FTOs) ionized in negative-ion APCI and APPI generated the molecular ion, while fluorotelomer alcohols (FTOHs) also provided the deprotonated molecule. Besides, fluorooctane sulfonamides (FOSAs) and sulfonamido-ethanols (FOSEs) led to the deprotonated molecule and in-source CID fragment ions, respectively. The fragmentation pathways from these precursor ions mainly involved initial α,ß-eliminations of HF units and successive losses of CF2 units coming from the perfluorinated alkyl chain. Moreover, FTOHs and FOSEs showed a high tendency to generate adduct ions under negative-ion ESI and APPI conditions. The fragmentation study of these adduct ions has demonstrated a strong interaction with the attached moiety. Graphical abstract.

4.
Anal Bioanal Chem ; 411(21): 5577-5591, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31172239

RESUMO

This work describes the development of an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for the determination of carotenoids (ß-carotene, lutein, ß-criptoxanthin, neoxanthin, violaxanthin) and chlorophylls, as well as their related compounds (chlorophyll A and B, pheophytin A and B and the banned dyes Cu-pyropheophytin A, Cu-pheophytin A and B) in olive oils. For this purpose, the feasibility of electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) for the ionization of these compounds was evaluated and compared. Tandem mass spectrometry (MS/MS) fragmentation was discussed for each family of compounds, and the most characteristic and abundant product ions were selected to propose a selective and sensitive UHPLC-MS/MS method. The best results were obtained using APCI and APPI, while ESI provided the worst signal-to-noise ratio (S/N) for all compounds. For the analysis of olive oils, a simple solid-phase extraction (SPE) with silica cartridges was applied before the determination by UHPLC-MS/MS (APCI and APPI) in multiple reaction monitoring (MRM) mode. Method quality parameters were stablished, and the results demonstrate the good performance of the new methods, providing low limits of detection (0.004-0.9 mg L-1), high extraction efficiencies (62-95%) and low matrix effects (< 25%). The developed UHPLC-API-MS/MS (APCI and APPI) methods were applied to the analysis of olive oil samples, and ß-carotene, pheophytin A, pheophytin B and lutein were detected and quantified in all of them at concentrations ranging from 0.1 to 9.5 mg L-1. Graphical abstract.


Assuntos
Cromatografia Líquida/métodos , Azeite de Oliva/química , Pigmentos Biológicos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Extração em Fase Sólida
5.
Artigo em Inglês | MEDLINE | ID: mdl-28067117

RESUMO

The occurrence of furan in commercial baby food samples from the Spanish market was evaluated using an automated headspace solid-phase microextraction method coupled to gas chromatography-mass spectrometry (HS-SPME-GC-MS). A total of 76 baby food samples including infant formula, baby cereals, fruit in cans and/or jars, vegetables, meat, and fish, were surveyed for furan content. The lowest concentration of this compound was found in infant formula (<0.02-0.33 ng ml-1), and cereal-based food (0.15-2.1 ng g-1) while baby food containing fish showed the highest concentrations (19-84 ng g-1). Following recommendation of the European Food Safety Authority (EFSA), the effect on furan content was evaluated of consumer home preparation of foods, heating and handling. Furan concentrations were reduced by up to 35% when samples were heated in a dish using microwave oven and by up to 53% when a hot water bath was used. Finally, we estimated the furan intake from baby food consumption (0.002-1.18 µg kg-1 body weight day-1) and we calculated the margin of exposure (MOE) from samples as purchased and also after home preparation of the food. For infant formula and cereal baby foods, the MOEs (26,278-412,776) indicated no infant health concern or priority, while for meat and fish-based baby foods the values pointed to a potential public health risk, even considering the furan losses during preparation at home.


Assuntos
Suplementos Nutricionais , Análise de Alimentos , Contaminação de Alimentos/análise , Furanos/análise , Alimentos Infantis/análise , Comércio , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactente , Nível de Efeito Adverso não Observado , Medição de Risco , Microextração em Fase Sólida , Espanha
6.
J Chromatogr A ; 1413: 107-16, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26298605

RESUMO

Ionization and in source-fragmentation behavior of four fluorotelomer alcohols (FTOH) (4:2 FTOH, 6:2 FTOH, 8:2 FTOH and 10:2 FTOH) and four N-alkyl fluorooctane sulfonamides/-ethanols (N-MeFOSA, N-EtFOSA, N-MeFOSE and N-EtFOSE) by APCI has been studied and compared with the traditionally used EI and CI. Protonated molecule was the base peak of the APCI spectrum in all cases giving the possibility of selecting it as a precursor ion for MS/MS experiments. Following, CID fragmentation showed common product ions for all FOSAs/FOSEs (C4F7 and C3F5). Nevertheless, the different functionality gave characteristic pattern fragmentations. For instance, FTOHs mainly loss H2O+HF, FOSAs showed the losses of SO2 and HF while FOSEs showed the losses of H2O and SO2. Linearity, repeatability and LODs have been studied obtaining instrumental LODs between 1 and 5fg. Finally, application to river water and influent and effluent waste water samples has been carried out in order to investigate the improvements in detection capabilities of this new source in comparison with the traditionally used EI/CI sources. Matrix effects in APCI have been evaluated in terms of signal enhancement/suppression when comparing standards in solvent and matrix. No matrix effects were observed and concentrations found in samples were in the range of 1-100pgL(-1) far below the LODs achieved with methods previously reported. Unknown related perfluoroalkyl substances, as methyl-sulfone and methyl-sulfoxide analogues for FTOHs, were also discovered and tentatively identified.


Assuntos
Álcoois/análise , Hidrocarbonetos Fluorados/análise , Sulfonamidas/análise , Pressão Atmosférica , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas em Tandem/métodos
7.
PLoS One ; 10(1): e0115505, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25629403

RESUMO

Located on the Iberian Mediterranean coast, El Collado is an open-air site where a rescue excavation was conducted over two seasons in 1987 and 1988. The archaeological work excavated a surface area of 143 m2 where 14 burials were discovered, providing skeletal remains from 15 individuals. We have obtained AMS dates for 10 of the 15 individuals by means of the direct dating of human bones. The ranges of the probability distribution of the calibrated dates suggest that the cemetery was used during a long period of time (781-1020 years at a probability of 95.4%). The new dates consequently set back the chrono-cultural attribution of the cemetery from the initial proposal of Late Mesolithic to an older date in the Early Mesolithic. Therefore, El Collado becomes the oldest known cemetery in the Iberian Peninsula, earlier than the numerous Mesolithic funerary contexts documented on the Atlantic façade such as the Portuguese shell-middens in the Muge and Sado Estuaries or the funerary sites on the northern Iberian coast.


Assuntos
Cemitérios , Arqueologia , Europa (Continente) , Humanos , Datação Radiométrica , Espanha
8.
Food Chem ; 126(4): 1902-8, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25213975

RESUMO

Micellar electrokinetic chromatography (MEKC) has been applied for the determination of 5-hydroxymethylfurfural in several foodstuffs. A 75mM phosphate buffer solution at pH 8.0 containing 100mM sodium dodecylsulphate was used as background electrolyte (BGE), and the separation was performed by applying +25kV in a 50µm I.D. uncoated fused-silica capillary. Good linearity over the range 2.5-250mgkg(-1) (r(2)⩾0.999) and run-to-run and day-to-day precisions at low and medium concentration levels were obtained. Sample limit of detection (0.7mgkg(-1)) and limit of quantification (2.5mgkg(-1)) were established by preparing the standards in blank matrix. The procedure was validated by comparing the results with those obtained with liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Levels of HMF in 45 different foodstuffs such as breakfast cereals, toasts, honey, orange juice, apple juice, jam, coffee, chocolate and biscuits were determined.

9.
J Chromatogr A ; 1185(1): 102-8, 2008 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-18272160

RESUMO

A new, simple and selective method for the analysis of 5-hydroxymethylfurfural (HMF) in foods by liquid chromatography coupled to ion trap multi-stage mass spectrometry (LC-MS(n)) is proposed in the present study. Several chromatographic columns were tested and the best results were obtained using a phenyl fluorinated column. MS conditions were established using an atmospheric pressure chemical ionisation (APCI) source in the positive ionisation mode. MS/MS was used for quantitative analysis while MS(3) was required for confirmation purposes. Quality parameters such as day-to-day and run-to-run precision (RSD<10%) and detection limit (133 ng g(-1), 333 pg injected) were established. This method was successfully applied to the analysis of HMF content in several Spanish food samples from a local market.


Assuntos
Cromatografia Líquida/métodos , Furaldeído/análogos & derivados , Espectrometria de Massas/métodos , Alimentos , Análise de Alimentos , Furaldeído/análise , Cromatografia Gasosa-Espectrometria de Massas
10.
J Agric Food Chem ; 55(26): 10531-9, 2007 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-18052095

RESUMO

This paper reports on the applicability of gas chromatography coupled to ion-trap tandem mass spectrometry (GC/ITMS/MS) for the analysis of polychlorinated dibenzo- p-dioxins (PCDDs), dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dl-PCBs) in food. MS/MS parameters were selected to achieve the high sensitivity and selectivity required for food analysis. Good precision (RSD=5-18% for PCDD/Fs and 6-14% for dl-PCBs) and low limits of detection for PCDD/Fs (0.1-0.93 pg/g of fat) and dl-PCBs (0.1-0.89 pg/g of fat) were obtained. A comparative study of the congener-specific determination using both GC/ITMS/MS and GC-high resolution mass spectrometry (GC/HRMS) was performed by analyzing several matrices such as milk, fish oil, chicken, pork, fish, eggs, and a chicken compound feed, at low pg/g levels. The results using GC/ITMS/MS were in good agreement with those obtained by GC/HRMS. Consequently, GC/ITMS/MS is proposed for the analysis of PCDD/Fs and dl-PCBs in food and feed samples.


Assuntos
Benzofuranos/análise , Dioxinas/análise , Análise de Alimentos/métodos , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análogos & derivados , Espectrometria de Massas em Tandem , Cromatografia Gasosa-Espectrometria de Massas , Dibenzodioxinas Policloradas/análise , Sensibilidade e Especificidade
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