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1.
Sci Total Environ ; 784: 147215, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34088076

RESUMO

The present work is the first extensive study of large-scale pesticides research in wild animals. The investigation covered three game species: wild boar (n = 42), roe deer (n = 79) and deer (n = 15) collected from north-eastern Poland. To characterize the 480 pesticides in muscle samples, LC-GC-MS/MS techniques were used. A total of 28 compounds were detected: 5 neonicotinoids, 6 organochlorine and 5 other insecticides, 9 fungicides and 4 herbicides, in the range of 0.1-85.3 ng g-1. Over four hundred detections were done. The highest mean concentrations were as follows: anthraquinone (85.3 ng g-1) > DDT-p,p' (4.6 ng g-1) > imidacloprid (4.3 ng g-1) > permethrin (3.6 ng g-1) > thiacloprid (2.8 ng g-1). DDT and metabolites were the most frequently detected, followed by acetamiprid, tebuconazole, clothianidin and imidacloprid. Overall, 92% samples with residues were recorded, including 100% of wild boar, 88% of roe deer and 86% of deer. More than one pesticide (up to 9) was found in over 73% of the tested samples. The estimated chronic and acute risk to consumers of venison were very low (below 1% ADI and ARfD). This interdisciplinary study may be helpful for estimating ecological risk to wild animals and risk to consumers of wild animal products, and also as a source of biomonitoring data.


Assuntos
Cervos , Praguicidas , Animais , Agricultura Florestal , Praguicidas/análise , Polônia , Medição de Risco , Sus scrofa , Suínos , Espectrometria de Massas em Tandem
2.
BMC Genomics ; 22(1): 417, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34090334

RESUMO

BACKGROUND: Intramuscular adipocytes differentiation is a complex process, which is regulated by various transcription factor, protein factor regulators and signal transduction pathways. However, the proteins and signal pathways that regulates goat intramuscular adipocytes differentiation remains unclear. RESULT: In this study, based on nanoscale liquid chromatography mass spectrometry analysis (LC-MS/MS), the tandem mass tag (TMT) labeling analysis was used to investigate the differentially abundant proteins (DAPs) related with the differentiation process of goat intramuscular adipocytes. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes enrichment and protein-protein interaction network analyses were performed for the characterization of the identified DAPs. The candidate proteins were verified by parallel reaction monitoring analysis. As a result, a total of 123 proteins, 70 upregulation proteins and 53 downregulation proteins, were identified as DAPs which may be related with the differentiation process of goat intramuscular adipocytes. Furthermore, the cholesterol metabolism pathway, glucagon signaling pathway and glycolysis / gluconeogenesis pathway were noticed that may be the important signal pathways for goat Intramuscular adipocytes differentiation. CONCLUSIONS: By proteomic comparison between goat intramuscular preadipocytes (P_IMA) and intramuscular adipocytes (IMA), we identified a series protein that might play important role in the goat intramuscular fat differentiation, such as SRSF10, CSRP3, APOH, PPP3R1, CRTC2, FOS, SERPINE1 and AIF1L, could serve as candidates for further elucidate the molecular mechanism of IMF differentiation in goats.


Assuntos
Cabras , Proteômica , Adipócitos , Animais , Cromatografia Líquida , Espectrometria de Massas em Tandem
3.
Rhinology ; 59(3): 328-336, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34091656

RESUMO

BACKGROUND: Exosomes are critical mediators of intercellular communication and could be involved in many human diseases; however, little is known about the role of exosomes in nasal polyps (NP). METHODS: Exosomes in nasal lavage fluids (NLF) were isolated by ultracentrifugation. Exosome identity was validated by nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM) and specific exosomal markers. The exosome proteome was revealed by LC-MS/MS, and the expression of the candidate exosomal protein, mucin 5AC, was confirmed by Western blot analysis and immunohistochemistry (IHC). Cellular uptake of the exosomes was monitored by fluorescence confocal microscopy and the ensuing effects on COX-2, VEGF and MMP-2/MMP-9 were determined by Western blotting, ELISA and gelatin zymography, respectively. RESULTS: Mass spectrometry analysis and subsequent verification by Western blotting identified that mucin 5AC was significantly upregulated in exosomes from NLFs of NP patients. Moreover, the expression of mucin 5AC was increased in the tissue specimens of the NP patients. Functional assays suggest that the mucin 5 AC-enriched exosomes could be effectively taken up by chronic rhinosinusitis without NP (CRSsNP)-derived fibroblasts, the control cells, resulting in a significant increase in the expression of COX-2, VEGF and MMP-9. CONCLUSIONS: Mucin 5AC, the major airway mucin, cannot only be carried and transferred by nasal exosomes, but may also promote tissue remodeling and angiogenesis and thus could be a potential therapeutic target of NP.


Assuntos
Exossomos , Pólipos Nasais , Cromatografia Líquida , Ciclo-Oxigenase 2 , Humanos , Metaloproteinase 9 da Matriz , Mucina-5AC , Líquido da Lavagem Nasal , Espectrometria de Massas em Tandem , Fator A de Crescimento do Endotélio Vascular
4.
Chemosphere ; 276: 130213, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34088095

RESUMO

Regulatory measures and public concerns regarding bisphenol A (BPA) have led to its replacement by a variety of alternatives in consumer products. Due to their structural similarity to BPA, these alternatives are under surveillance, however, for potential endocrine disruption. Understanding the materno-fetal transfer of these BPA-related alternatives across the placenta is therefore crucial to assess prenatal exposure risks. The objective of the study was to assess and compare the placental transfer of a set of 15 selected bisphenols (BPs) (BP 4-4, BPA, BPAF, BPAP, 3-3 BPA, BPB, BPBP, BPC, BPE, BPF, BPFL, BPM, BPP, BPS and BPZ) using the ex vivo human placental perfusion model. The UHPLC-MS/MS method for simultaneous quantification of these BPs in perfusion media, within a concentration range of 0.003-5 µM, was able to measure placenta transfer rates as low as 0.6%-4%. Despite their structural similarities, these BPs differed greatly in placental transport efficiency. The placental transfer rates of BP4-4, BPAP, BPE, BPF, 3-3BPA, BPB, BPA were similar to that of antipyrine, indicating that their main transport mechanism was passive diffusion. By contrast, the placental transfer rates of BPFL and BPS were very limited, and intermediate for BPBP, BPZ, BPC, BPM, BPP and BPAF, suggesting weak diffusional permeability and/or that their passage might involve efflux transport. These placental transfer data will be particularly useful for predicting the fetal exposure of this important class of emerging contaminants.


Assuntos
Placenta , Espectrometria de Massas em Tandem , Compostos Benzidrílicos , Feminino , Humanos , Perfusão , Fenóis , Gravidez
5.
J Chromatogr A ; 1650: 462256, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34082187

RESUMO

An analytical method based on low-temperature partitioning extraction (LTPE) followed by high performance liquid chromatography coupled to triple quadrupole mass spectrometry analysis was developed and validated for the determination of eight multiclass antibiotics in wastewater. The analyzed target antibiotics included one ß-lactam, two sulfonamides, three fluoroquinolones, one macrolide and one diaminopyrimidine. LTPE parameters such as sample pH, volume ratio between sample and extractor solvent, ultra-sonic extraction time, extraction tube material, solvent and volume to reconstitute the sample extracts, were optimized. Additionally, the influence of solids on extraction efficiency was evaluated. Quantification of the target antibiotics was performed by double consecutive injection method, without the use of a labeled compound, in order to correct matrix effects. The whole samples were analyzed, including, liquid and solid fractions of wastewater. The results revealed that the filtration step can underestimate the total antibiotics concentration, particularly to the hydrophobic compounds that have higher affinity for solids, indicating that the suspended wastewater particulate should not be neglected. The method detection limit ranged from 18.54 ng L-1 (trimethoprim) to 78.49 ng L-1 (ciprofloxacin). Intra-day precision of less than 12.3% was achieved. The recoveries values ranged from 13.9% (sulfadiazine) to 48.9% (erythromycin) in influent samples and from 19.1% (sulfadiazine) to 57.2% (ciprofloxacin) in effluent samples. The method was applied to the measurement of antibiotic residues in influent and effluent from wastewater treatment plants. The majority target antibiotics were detected in wastewater samples. Their concentrations ranged from 237 to 9553 ng L-1 in influent and from 212 to 1660 ng L-1 in effluent. This work provides new insights on the applicability of LTPE for antibiotic residues extraction from wastewater. In addition, the performed analysis highlights the importance of measuring total concentrations of analytes in whole sample.


Assuntos
Antibacterianos , Técnicas de Química Analítica , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Águas Residuárias , Poluentes Químicos da Água , Antibacterianos/análise , Técnicas de Química Analítica/instrumentação , Técnicas de Química Analítica/métodos , Temperatura Baixa , Interações Hidrofóbicas e Hidrofílicas , Extração em Fase Sólida , Águas Residuárias/química , Poluentes Químicos da Água/análise
6.
J Chromatogr A ; 1650: 462228, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34090133

RESUMO

Bioactive 11-oxygenated C19 adrenal-derived steroids (11-oxy C19) are potentially relevant in diverse endocrine and metabolic contexts. We report the development and validation of a liquid chromatography electrospray ionization tandem mass spectrometric method (LC-ESI-MS/MS) for the simultaneous quantification of seven 11-oxy C19 using 200 µL of plasma or serum. Sample preparation involved chemical derivatization using hydroxylamine after liquid-liquid extraction to improve specificity and sensitivity. The method allowed the quantitation of total 11-oxy C19 (free + sulfate and glucuronide conjugates) following enzymatic hydrolysis. This included the abundant precursor 11-hydroxyandrostenedione (11OHA4) and the most potent androgenic derivatives 11-keto-testosterone (11KT) and 11-keto-dihydrotestosterone (11KDHT), their abundant metabolites 11-hydroxyandrosterone (11OHAST) and 11-keto-androsterone (11KAST) potentially feeding back into the pool of potent androgens, in addition to 11-keto-androstenedione (11KA4) and 11-hydroxytestosterone (11OHT). Stable isotopes were used as internal standards, and calibrators and quality controls were prepared in the same matrix as the study samples. Performance was validated against the Food and Drug Administration Criteria. The method was sensitive with lower limit of quantification (LLOQ) values of 10 and 20 pg/mL for free and total 11-oxy C19, respectively. The applicability was demonstrated in men and women adult donors that showed sex-differences. All steroids were quantified well above LLOQ, except 11KDHT that remained undetectable suggesting interfering endogenous molecules present in non-derivatized samples in which a peak was observed. By providing accurate and reliable quantitative data, this method will permit to evaluate how profiling of 11-oxy C19 will be most informative as diagnostic, prognostic and/or theranostic tools.


Assuntos
Androgênios , Análise Química do Sangue , Cromatografia Líquida , Espectrometria de Massas em Tandem , Adulto , Androgênios/sangue , Androstenodiona/análogos & derivados , Androstenodiona/sangue , Análise Química do Sangue/métodos , Feminino , Glucuronídeos , Humanos , Hidroxitestosteronas/sangue , Limite de Detecção , Masculino , Oxigênio/química , Esteroides/sangue , Testosterona/análogos & derivados , Testosterona/sangue
7.
Front Public Health ; 9: 666787, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095069

RESUMO

Objectives: Despite the widespread use of manganese (Mn) in industrial settings and its association with adverse neurological outcomes, a validated and reliable biomarker for Mn exposure is still elusive. Here, we utilize targeted metabolomics to investigate metabolic differences between Mn-exposed and -unexposed workers, which could inform a putative biomarker for Mn and lead to increased understanding of Mn toxicity. Methods: End of shift spot urine samples collected from Mn exposed (n = 17) and unexposed (n = 15) workers underwent a targeted assay of 362 metabolites using LC-MS/MS; 224 were quantified and retained for analysis. Differences in metabolite abundances between exposed and unexposed workers were tested with a Benjamini-Hochberg adjusted Wilcoxon Rank-Sum test. We explored perturbed pathways related to exposure using a pathway analysis. Results: Seven metabolites were significantly differentially abundant between exposed and unexposed workers (FDR ≤ 0.1), including n-isobutyrylglycine, cholic acid, anserine, beta-alanine, methionine, n-isovalerylglycine, and threonine. Three pathways were significantly perturbed in exposed workers and had an impact score >0.5: beta-alanine metabolism, histidine metabolism, and glycine, serine, and threonine metabolism. Conclusion: This is one of few studies utilizing targeted metabolomics to explore differences between Mn-exposed and -unexposed workers. Metabolite and pathway analysis showed amino acid metabolism was perturbed in these Mn-exposed workers. Amino acids have also been shown to be perturbed in other occupational cohorts exposed to Mn. Additional research is needed to characterize the biological importance of amino acids in the Mn exposure-disease continuum, and to determine how to appropriately utilize and interpret metabolomics data collected from occupational cohorts.


Assuntos
Manganês , Exposição Ocupacional , Cromatografia Líquida , Humanos , Manganês/toxicidade , Metabolômica , Exposição Ocupacional/efeitos adversos , Espectrometria de Massas em Tandem
8.
Chemosphere ; 278: 130409, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34126677

RESUMO

Testing and assessing the persistency, bioaccumulative and toxic properties of UVCBs (substances of Unknown or Variable composition, Complex reaction products or Biological materials) pose major technical and analytical challenges. The main aim of this study was to combine whole substance biodegradation testing with constituent specific analytics for determining primary biodegradation kinetics of the main UVCB constituents. An additional aim was to link the primary biodegradation kinetics of the main constituents to the bioaccumulation potential and baseline toxicity potential of the UVCB. Two closed biodegradation experiments were conducted using similar test systems but different analyses. The model substance, cedarwood Virginia oil, was tested at a low concentration and wastewater treatment plant effluent served as inoculum. We used microvolume solvent spiking for a quantitative mass transfer of the UVCB, while avoiding that co-solvent degradation would lead to anaerobic conditions. The biodegradation of UVCB constituents was determined with automated solid-phase microextraction coupled to GC-MS/MS using targeted analysis for main constituents and non-targeted analysis for minor constituents and non-polar degradation products. Primary biodegradation kinetics of main constituents, accounting for 73% w/w of the mixture, were successfully determined with degradation rate constants ranging from 0.09 to 0.25 d-1. Minor constituents were also degraded and non-polar degradation products were not observed. Finally, the bioaccumulation potential and baseline toxicity potential of the mixture at test start were calculated and both parameters decreased then substantially. The strength of the new approach is the possibility of biodegradation testing of a whole UVCB at low concentration while generating constituent specific biodegradation kinetics.


Assuntos
Óleos Voláteis , Espectrometria de Massas em Tandem , Biodegradação Ambiental , Cinética , Virginia
9.
Plant Physiol Biochem ; 165: 228-238, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34077875

RESUMO

In grape cell cultures cv. Gamay Fréaux var. Teinturier, Ca was shown to decrease cell pigmentation through the inhibition of anthocyanin biosynthesis, while stimulating stilbenoids accumulation. Because methyl jasmonate (MeJA) is a well-known inducer of secondary metabolism in grape cells, and Ca antagonizes its stimulatory effect over several enzymes of core metabolic branches, in the present study we hypothesized that Ca and MeJA signaling pathways interact to regulate specific secondary metabolism routes. Grape cultured cells were elicited with MeJA or with MeJA + Ca and an UPLC-MS-based targeted metabolomic method was implemented to characterize their polyphenolic profiles. Results were compared with the profile of cells elicited with Ca only, previously reported. Data was complemented with gene expression analysis, allowing the assembly of a metabolic map that unraveled routes specifically regulated by both elicitors. MeJA + Ca specifically boosted E-resveratrol and E-ε-viniferin levels by 180% and 140%, respectively, in comparison to cells treated with MeJA only, while the stimulatory effect of MeJA over flavonoid synthesis was inhibited by Ca. In parallel, Ca downregulated most flavonoid pathway genes, including LAR1, ANS, BAN and ANR. Ca was able to mimic or potentiate the effect of MeJA on the expression of JA signaling genes, including JAR1, PIN and PR10. Transcript/metabolite correlation networks exposed the central influence of FLS1,STS,CDPK17 and COI1 in polyphenolic biosynthetic routes. This study highlights the potential of the MeJA-Ca combination for diverting polyphenolic metabolism towards the production of specific metabolites of interest, highly relevant in a biotechnological perspective.


Assuntos
Vitis , Acetatos/farmacologia , Cálcio , Cromatografia Líquida , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas , Oxilipinas/farmacologia , Metabolismo Secundário , Espectrometria de Massas em Tandem , Vitis/genética
10.
Wei Sheng Yan Jiu ; 50(3): 488-494, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34074374

RESUMO

OBJECTIVE: To establish a rapid and accurate method for the determination of trace acetaldehyde, acrolein, methacrylaldehyde, crotonaldehyde in the air by ultra-fast liquid chromatography-tandem mass spectrometry(UFLC-MS/MS). METHODS: The air sample was concentrated and derivatived by 3-methyl-2(3 H)-benzothiazolonhydrazone(MBTH), and the effect of derivative conditions including the concentration of MBTH, the pH, the derivative time and temperature was investigated. The stability of derivatives, the cracking mechanism of mass spectrometry, the matrix effect of the method and air sampling efficiency were studied. The chromatographic separation was carried out on a Shim-pack XR-ODS II column(100 mm×2. 0 mm, 2. 2 µm) by using water/methanol solution as the mobile phase with the gradient elution. Detection was performed in positive multi-reaction monitoring(MRM) mode for quantification by using external standard method. RESULTS: The four analytes showed good linear relationship within the range of 1. 00-100 µg/L(calculated by aldehyde) with a correlation coefficient r≥0. 9990. The limits of quantitation(LOQs) of the method(concentrated with 10 L air) were 0. 5 µg/m~3 in air, for acetaldehyde, acrolein, methacrylaldehyde, crotonaldehyde. The recoveries of the method were 90. 6%-97. 8% at the three spiked levels, and the relative standard deviations(RSDs) were between 1. 9%-6. 4%(n=6), the average sampling efficiency was between 91. 0%-97. 1%. CONCLUSION: The developed method is simple, less interference and specificity, and is suitable for the simultaneous rapid determination of trace acetaldehyde, acrolein, methacrylaldehyde, crotonaldehyde in air of work place.


Assuntos
Aldeídos , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida
11.
J Agric Food Chem ; 69(22): 6330-6338, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34060319

RESUMO

Citrinin (CIT) is a scarcely studied mycotoxin within foodstuffs, so the biomonitoring of this toxin and its metabolite dihydrocitrinone (DH-CIT) in biological samples represents the main alternative to estimate the exposure. Hence, this study aimed to evaluate the presence of CIT and DH-CIT in 300 urine samples from Italian individuals in order to assess the exposure. Quantification was performed through an ultrahigh-performance liquid chromatography high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS)-based methodology. CIT was quantified in 47% of samples (n = 300) up to 4.0 ng/mg Crea (mean = 0.29 ng/mg Crea), whereas DH-CIT was quantified in 21% of samples up to 2.5 ng/mg Crea (mean = 0.39 ng/mg Crea). Considering different age groups, average exposure ranged from 8% to 40% of the provisional tolerable daily intake, whereas four individuals surpassed the limits suggested by the European Food Safety Authority. These results revealed non-negligible exposure levels to CIT, encouraging further investigation in foodstuffs monitoring studies.


Assuntos
Citrinina , Monitoramento Biológico , Biomarcadores , Cromatografia Líquida de Alta Pressão , Exposição Dietética , Humanos , Espectrometria de Massas em Tandem
12.
Chemosphere ; 279: 130544, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34134402

RESUMO

This study aiming to determine the optimal conditions to degrade an organophosphate pesticide diazinon (DZN) at low levels concentrations (µg.mL-1) and to identify the by-products generated. The degradation processes utilized were the Fenton and photo-Fenton. The iron concentration [Fe2+], the hydrogen peroxide concentrations [H2O2], and the solution pH are the investigated parameters. The Doehlert three-parameter experimental design was applied to model and optimize both degradation processes. The mathematical models suggested were assessed and validated by application of analysis of variances ANOVA. In the case of Fenton process, the greatest yield of degradation (79%) was obtained at [Fe2+] = 35 mg.L-1 (0.63 mmol.L-1), [H2O2] = 423 mg.L-1 (12.44 mmol.L-1), and pH = 5.0. In photo-Fenton process, the maximum yield of degradation (96%) was obtained under the conditions of [Fe2+] = 29 mg.L-1 (0.52 mmol.L-1), [H2O2] = 258 mg.L-1 (7.59 mmol.L-1) and pH = 4.6. QuEChERS (quick, easy, cheap, effective, rugged, and safe), as extraction technique, and GC-MS/MS (gas chromatography coupled with triple quadrupole mass spectrometry) were used to identify the by-products degradation of DZN. The identified compounds are diazoxon, triethyl phosphate, triethyl thiophosphate, 2-isopropyl-5-ethyl-6-methylpyrimidine-4-ol, 2-isopropyl-6-methylpyrimidine-4-ol (IMP) and hydroxydiazinon. Three possible pathways for diazinon degradation have been suggested and the hydroxylation, oxidation and hydrolysis are likely probable degradation mechanisms.


Assuntos
Praguicidas , Poluentes Químicos da Água , Cromatografia Gasosa-Espectrometria de Massas , Peróxido de Hidrogênio , Oxirredução , Espectrometria de Massas em Tandem , Raios Ultravioleta , Água
13.
Chemosphere ; 279: 130923, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34134442

RESUMO

Historical use of organochlorine pesticides (OCPs) in the Republic of Moldova could pose a potential risk for the aquatic environment due to the persistence, bioaccumulation and toxic properties of these environmental pollutants. However, knowledge on environmental concentrations of legacy OCPs in Moldova is limited. In this study, surface sediment from the two main rivers; Dniester (8 sites, n = 15) and Prut (6 sites, n = 12), and two tributary rivers; Bîc (11 sites, n = 11) and Raut (6 sites, n = 6), were collected during 2017-2018 and analyzed for hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and their transformation products (DDDs and DDEs) using gas chromatography coupled to mass spectrometry (GC-MS/MS). Sediment concentrations of Æ©6DDX (1.9-140 ng g-1 dry weight (dw)) and Æ©4HCHs (n.d-2.5 ng g-1 dw) were found. In the big rivers, the average Æ©6DDX concentration (18 ng g-1 dw) were 35 times higher than Æ©4HCHs (0.51 ng g-1 dw). Whereas, in the small rivers the average Æ©6DDX concentration (32 ng g-1 dw) was approximately 41 times higher than Æ©4HCHs (0.77 ng g-1 dw). Compared to previous studies from Eastern Europe, the sediment levels were generally similar as found in Moldova's neighboring countries (Romania and Ukraine). Overall, the contamination profile indicates long-term ageing of OCPs used in the past in the agricultural sector. Less than half of the sites (45%) had levels that pose a potential risk for benthic organisms. Hence, further work is needed to determine the bioaccumulation of OCPs in the aquatic food web in this region and the associated risks to ecosystems and human health.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Poluentes Químicos da Água , China , Ecossistema , Monitoramento Ambiental , Europa Oriental , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos , Humanos , Hidrocarbonetos Clorados/análise , Moldávia , Praguicidas/análise , Rios , Romênia , Espectrometria de Massas em Tandem , Ucrânia , Poluentes Químicos da Água/análise
14.
Talanta ; 232: 122400, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074394

RESUMO

Ciguatera food poisoning affects consumer health and fisheries' economies worldwide in tropical zones, and specifically in the Pacific area. The wide variety of ciguatoxins bio-accumulated in fish or shellfish responsible for this neurological illness are produced by marine dinoflagellates of the genus Gambierdiscus and bio-transformed through the food web. The evaluation of the contents of ciguatoxins in strains of Gambierdiscus relies on the availability of standards and on the development of sensitive and specific tools to detect them. There is a need for sensitive methods for the analysis of pacific ciguatoxins with high resolution mass spectrometry to ensure unequivocal identification of all congeners. We have applied a fractional factorial design of experiment 2^8-3 for the screening of the significance of eight parameters potentially influencing ionization and ion transmission and their interactions to evaluate the behavior of sodium adducts, protonated molecules and first water losses of CTX4A/B, CTX3B/C, 2-OH-CTX3C and 44-methylgambierone on a Q-TOF equipment. The four parameters that allowed to significantly increase the peak areas of ciguatoxins and gambierones (up to a factor ten) were the capillary voltage, the sheath gas temperature, the ion funnel low pressure voltage and the ion funnel exit voltage. The optimized method was applied to revisit the toxin profile of G. polynesiensis (strain TB92) with a confirmation of the presence of M-seco-CTX4A only putatively reported so far and the detection of an isomer of CTX4A. The improvement in toxin detection also allowed to obtain informative high resolution targeted MS/MS spectra revealing high similarity in fragmentation patterns between putative isomer (4) of CTX3C, 2-OH-CTX3C and CTX3B on one side and between CTX4A, M-seco-CTX4A and the putative isomer on the other side, suggesting a relation of constitutional isomerism between them for both isomers.


Assuntos
Intoxicação por Ciguatera , Ciguatoxinas , Dinoflagelados , Animais , Cromatografia Líquida de Alta Pressão , Ciguatoxinas/análise , Espectrometria de Massas em Tandem
15.
Talanta ; 232: 122437, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074422

RESUMO

Breast cancer is one of the most malignant diseases among females. N-glycoproteomics studies have shown that N-glycosylation alteration of tumor cells is the key player of cancer progression, multidrug resistance (MDR) and high mortality. Cancer stem cells (CSCs) have the remarkable potential of self-renewing and differentiation which leads to drug resistance and metastasis. To investigate the differentially expressed N-glycosylation in adriamycin-resistant breast cancer stem cells MCF-7/ADR CSCs (relative to MCF-7 CSCs) and find the putative biomarkers, 1:1 paired ZIC-HILIC-enriched and stable isotopic diethyl labelled (SIDE) intact N-glycopeptides from MCF-7/ADR CSCs and MCF-7 CSCs were analyzed with C18-RPLC-ESI-MS/MS (HCD with stepped NCE); differentially expressed intact N-glycopeptides (DEGPs) were identified and quantified via search engine GPSeeker. With control of spectrum-level FDR≤1%, 5515 intact N-glycopeptides were identified (1737 N-glycosites, 1705 peptide backbones and 1516 intact N-glycoproteins; 181 putative N-glycan linkages and 68 monosaccharide compositions). Among 5515 intact N-glycopeptide IDs, 3864 were identified with glycoform score≥1, i.e., one or more structure-diagnostic fragment ions were observed to distinguish sequence isomers. With the three technical replicates and the criteria of fold change≥1.5 and p value<0.05, 380 DEGPs (corresponding to 153 intact N-glycoproteins) were found along with 293 down-regulated and 87 up-regulated. For these 153 intact N-glycoproteins, the molecular functions and biological processes of were comprehensively discussed, and side-to-side comparison of differential expression results with other method were also made.


Assuntos
Neoplasias da Mama , Espectrometria de Massas em Tandem , Biomarcadores , Feminino , Glicopeptídeos , Glicoproteínas , Humanos , Células MCF-7 , Células-Tronco Neoplásicas , Proteômica
16.
Talanta ; 232: 122438, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074423

RESUMO

UPLC-MS/MS methods are the gold standard for routine, high-throughput measurements of biogenic monoamines for the diagnosis of catecholamine-producing tumors. However, this cannot be achieved without employing efficient sample pretreatment methods. Therefore, two pretreatment methods, thin-film solid phase microextraction (TF-SPME) and packed fibers solid phase extraction (PFSPE), were developed and evaluated for the analysis of biogenic monoamines and their metabolites in urine. A hydrophilic-lipophilic balance (HLB) coating was chosen for the thin-film blade format SPME method and compared with a Polycrown ether (PCE) composite nanofiber used as an adsorbent for the PFSPE method. Under optimal conditions, the absolute extraction recovery and relative matrix effect of the newly developed TF-SPME method were determined to be 35.7-74.8% and 0.47-3.63%, respectively. The linearity was 0.25-500 ng mL-1 for norepinephrine, epinephrine, dopamine, normetanephrine 3-methoxytyramine, serotonin, histamine, and 0.1-500 ng mL-1 for metanephrine. The intra-and inter-assay coefficients of variation were 0.7-8.7%, and the respective accuracies were calculated to be 90.8-104.7% and 89.5-104.5% for TF-SPME. Compared with the PFSPE method, the TF-SPME method had a higher extraction efficiency, lower matrix effects and a wider linear range for eight target substances, which ensured higher accuracy of simultaneous detection of all compounds of interest. Therefore, the proposed TF-SPME method can be employed for the high throughput screening for neuroendocrine tumors in a routine clinical setting and other relative research by simultaneous quantitation of urine eight biological monoamines in a single run.


Assuntos
Microextração em Fase Sólida , Espectrometria de Massas em Tandem , Monoaminas Biogênicas , Cromatografia Líquida , Reprodutibilidade dos Testes
17.
Talanta ; 232: 122443, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074428

RESUMO

Wastewater-based epidemiology (WBE) employs the analysis of human metabolic biomarkers in influent wastewater (IWW) to estimate community-wide exposure to xenobiotics (e.g. prescription opioids). The low ng/L range of concentrations of these biomarkers and the complex matrix composition pose bioanalytical challenges related to sample preparation and detection/quantification. Therefore, a sensitive analytical method for the detection and analysis of 19 opioid biomarkers was optimized and validated according to the European Medicines Agency guidelines. Oasis HLB cartridges were used for sample concentration and an Atlantis T3 column with gradient elution resulted in sufficient separation of the analytes. Absolute recoveries (RE) were highly reproducible and ranged between 50 and 93% with the exception of 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP). The lower limit of quantification (LLOQ) ranged between 1 and 100 ng/L and was based on the analyte concentrations found in IWW. Process efficiency was acceptable for all biomarkers for which an isotope-labelled deuterated analogue was available. All biomarkers showed high benchtop stability with the exception of buprenorphine, EDDP, fentanyl and normorphine. Apart from buprenorphine and hydrocodone, all analytes under investigation were detected at least once above LLOQ levels in five locations in Belgium. The highest population-normalized mass loads were found for tramadol, O-desmethyltramadol and codeine. The proposed methodology was able to evaluate spatial differences in opioid use.


Assuntos
Analgésicos Opioides , Águas Residuárias , Bélgica , Fentanila , Humanos , Espectrometria de Massas em Tandem , Águas Residuárias/análise
18.
Talanta ; 232: 122466, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074438

RESUMO

Organophosphate flame retardants (OPFRs) are widely used in consumer products and building materials, but their propensity for migration poses a problem with respect to polluting indoor environments, water, soil, and dust. OPFR metabolites in urine samples are appropriate biomarkers for assessing exposure risk levels. In this paper, a high-throughput method that couples 96-blade solid-phase microextraction with ultra-performance liquid chromatography-tandem mass spectrometry (SPME-UPLC-MS/MS) is applied for the simultaneous detection of four OPFR metabolites in urine samples. The results indicated that the best extraction was achieved using 96 blades coated with hydrophilic-lipophilic balance weak anion exchange (HLB-WAX). The proposed SPME method's extraction efficiency was maximized by optimizing extraction time, pH value, desorption solution, desorption volume, and desorption time, and it was validated in accordance with the Food and Drug Administration's guidelines. The findings indicated that the proposed method has a wide linearity range (0.5-100 ng mL-1) and low detection limits (0.09-0.14 ng mL-1). The method's accuracy ranged from 98% to 118%, with intra-day precision ranging from 1% to 10%. In contrast, inter-day precision ranged from 3% to 16%. Accuracy was also evaluated using independent urine samples, which ranged from 78% to 124% with corresponding relative standard deviations (1%-16%). Ultimately, DoCP was detected in two real samples at a concentration of 0.5-1.1 ng mL-1, and BEHP was detected at a concentration of 0.2-1.2 ng mL-1. Overall, the proposed SPME-UPLC-MS/MS method is reliable, accurate, and capable of simultaneously determining four OPFR metabolites in urine samples and screening them to assess exposure risk for humans.


Assuntos
Retardadores de Chama , Monitoramento Biológico , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Retardadores de Chama/análise , Humanos , Organofosfatos , Microextração em Fase Sólida , Espectrometria de Massas em Tandem
19.
J Chromatogr A ; 1648: 462190, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33979756

RESUMO

A two-dimensional capillary isotachophoresis-capillary zone electrophoresis method hyphenated with tandem mass spectrometry was developed and validated for ultrasensitive quantification of serotonin in real human urine samples. Under optimal conditions, the separation was achieved within 12 min (including on-line sample preparation) with the limit of detection of 34 pg mL-1 (due to a large volume sample injection, here 10 µL, and isotachophoretic preconcentration). This concentration limit represents the lowest value for serotonin in comparison to other previously published separation methods employing mass spectrometry detection and applied to urine matrices. Thanks to high orthogonality, on-line concentration and clean-up effects of this approach, other excellent validation parameters such as linearity (coefficient of determination > 0.99), inter-day and intra-day precision (relative standard deviations 3.5-12.2%), accuracy (relative errors within 99-109.4%), and recovery (96-102%) could be easily obtained too. To demonstrate applicability of the method, we monitored serotonin levels in various real samples (from a healthy volunteer and clinical ones). The determined levels, normalized on the creatinine concentrations, were in the range of 6.81-12.86 ng mmol-1 creatinine This advanced method is suggested for an effective, reliable, high sample throughput, and low cost routine clinical screening or targeted metabolomic studies of serotonin in urine samples.


Assuntos
Eletroforese Capilar/métodos , Isotacoforese/métodos , Serotonina/urina , Espectrometria de Massas em Tandem/métodos , Creatinina/urina , Humanos , Limite de Detecção
20.
J Chromatogr A ; 1648: 462208, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34000594

RESUMO

Public exposure to pesticides through tobacco has attracted serious attention. Here we report a simultaneous screening and quantitation method for the non-target multiresidue analysis of pesticides in different tobacco types. The method involved extraction of a homogenate (20 g, containing 2 g tobacco) in ethyl acetate (10 mL), cleanup of 2 mL extract by dispersive solid phase extraction with PSA (50 mg)+C18 (50 mg)+GCB (25 mg)+MgSO4 (100 mg), followed by reconstitution in 1 mL acetonitrile:water (3:7) and analysis using HPLC with Quadrupole-Orbitrap mass spectrometry. The high resolution accurate mass analysis was performed through sequential full-scan (resolution=35000) and variable data independent acquisition (resolution=17500) events. When the method was evaluated in a mixture of 181 pesticides, it effectively minimised matrix interferences and false negatives. The target compounds included 5 pairs of isomers and 27 pairs of isobars, which were distinguished based on chromatographic separation, mass resolving power and/or unique product ions. The screening detection limit (SDL) for 86.4% of the test pesticides was set at 5 ng/g, while the remainder had the SDLs at 10 ng/g (9.3%) and 40 ng/g (4.3%). Nearly, 75% of the compounds showed recoveries of 70-120% at 10 ng/g. The rest of the compounds showed satisfactory recoveries at 40 and 100 ng/g. In all cases, precision-RSDs were < 20%. The established method demonstrated a successful performance in four different types of tobacco matrices while aligning with the guidelines of SANTE and US-FDA. Owing to its efficiency, the method is recommended for screening and quantitation of multiclass pesticides in tobacco.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Tabaco/química , Limite de Detecção , Praguicidas/análise , Extração em Fase Sólida/métodos , Produtos do Tabaco/análise
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