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1.
Foods ; 12(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36613396

RESUMO

Stingless bee honey (SBH) is gaining attention due to its nutritional, sensorial, and medicinal characteristics. This study focuses on the combination of physicochemical properties, antioxidant capacity, mineral profile, and mass spectrometry-based fingerprints, using a chemometric approach to differentiate SBH (n = 18) from three different Brazilian biogeographical zones (Caatinga, Cerrado, and Atlantic Forest). The physicochemical properties of SBH varied, resulting in a wide range of water activity, moisture, total soluble solids, pH, and total and free acidity. The Caatinga honey showed the highest and the lowest contents of phenolics and flavonoids, respectively. The antioxidant free-radical scavenging assays demonstrated that the Brazilian SBH has a high antioxidant potential. The mineral profile of honey samples from the Atlantic Forest revealed higher contents of Ca and Fe while the Cerrado and Caatinga honey showed the highest P contents. Partial Least-Squares Discriminant Analysis (PLS-DA) analysis separated the samples into three groups based on the biogeographical zones of harvest. The main separation factors between groups were the m/z 326 ion and the Fe content. Univariate analysis confirmed that Fe content is important for SBH discrimination. The present results indicate that the origin of SBH can be determined on the basis of mineral profile, especially Fe content.

2.
J Am Soc Mass Spectrom ; 33(8): 1510-1517, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35866646

RESUMO

Naphthenic acids comprise one of the most toxic compounds of the produced water released from offshore oil platforms. Therefore, developing and applying faster, simpler, and more efficient analytical methods for analyzing naphthenic acids are urgently needed. Electromembrane extraction (EME) uses the electrokinetic migration of target ions through a porous membrane. Herein, the EME method was applied to extract naphthenic acids from produced water. The EME method was optimized, and the optimal conditions encompassed decanol as the organic solvent, the sample with pH 10.0, 5 min of extraction at 200 V, and the ratio 4:1 (borate buffer/matrix, v/v). Electrochemical impedance spectroscopy confirmed charged species' migration from produced water through the EME. Subsequently, all extracts were analyzed by ultra-high-resolution mass spectrometry. The EME efficiency was assessed by comparing the extraction results to the liquid-liquid extraction (LLE) method results. Analytical results showed good linearity for both solvent and matrix curves (R2 > 0.98). Low detection limits ranged from 0.10 to 0.13 µg mL-1 and quantification limits from 0.36 to 0.45 µg mL-1. Precision and accuracy values ranged from -13.3% to 16.5%. These values fit the proposed method, demonstrating that the EME was more efficient than LLE in naphthenic acid extraction. The EME method preferably extracted aromatic compounds with double-bond equivalence from 6 to 8. The EME coupled with ultra-high-resolution mass spectrometry was demonstrated as a promising analytical approach to naphthenic acid extraction as an efficient and more environmentally friendly alternative to conventional extraction methods.


Assuntos
Membranas Artificiais , Água , Ácidos Carboxílicos , Espectrometria de Massas , Solventes/química , Água/química
3.
J Food Sci Technol ; 59(6): 2510-2515, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35602426

RESUMO

The indiscriminate utilization of agrochemicals causes environmental and animal life impacts. In this regard, methodologies have been developed to offer efficiency and quickness for agrochemicals detection. Due to their selectivity and molecular recognition sites, Molecular Imprinted Polymer (MIPs) have been widely employed in some areas, including biotechnology, waste analyses, foodstuff, biological fluids, and others. This work proposed developing a method to determine aminocarb, pirimicarb, dimethoate, omethoate, pyridaphenthion, and fenitrothion pesticides using molecularly imprinted polymer combined with solid-phase extraction (MIP-SPE) for clean-up and paper spray ionization mass spectrometry for their analysis. Extractions analysis for Aminocarb, Pirimicarb, and Omethoate using MIP-SPE showed better performance when compared with MIP and NIP. The R 2 values were found with R 2 > 0.98 for all pesticides, and LODs and LOQs values were 50 and 100 µg kg-1, respectively. The precision and accuracy were assessed at three concentration levels-low, medium, and high. The precision values (interday and intraday) were below 10%, and the variation of recovery was between 80 and 120% for all pesticides. Therefore, it was possible to verify the presence of two carbamates and five organophosphorus without the necessity of preconcentration samples with precision and good recovery. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05464-7.

4.
Anal Methods ; 13(44): 5274-5281, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34704566

RESUMO

This work describes the surface coating of wooden toothpicks with amino groups (NH2) for electrospray ionization mass spectrometry (MS) analysis of naphthenic acids (NAs) in produced water samples and crude oil fractions. NH2 was introduced into the cellulosic material through a silanization reaction using aminopropyltriethoxysilane. An NH2-modified toothpick was inserted into the analyte extraction sample and was subsequently used as an electrospray emitter for MS analysis. The extraction conditions were optimized by analyzing NAs (benzoic acid, 1-naphthoic acid, decanoic acid, 3,5-dimethyladamantane-1-carboxylic acid, and 3,5-dimethyladamantane-1-acetic acid) in pure water, and the best condition was using 5 min of extraction time with the samples under agitation. Modified and unmodified wooden toothpicks were compared, and the intensities of all NAs were higher when using the modified substrates than when using the unmodified ones. Limit of detection (LOD), limit of quantification (LOQ), linearity, precision, and recovery were determined by analyzing decanoic acid in seawater samples. The LOD and LOQ were 2 and 5 µg mL-1, respectively, and a linear correlation (R2 = 0.9927) was obtained with concentrations ranging from 5 to 250 µg mL-1. Precision values ranged from 6 to 13% and recoveries from 89 to 106%. The technique was also employed to analyze three produced water samples, in which decanoic acid was semi-quantified, and the concentrations ranged from 10 to 13 µg mL-1. High abundances of acidic compounds of class O2 with DBEs (double bond equivalents) ranging from 1 to 3 and carbon numbers going from 8 to 12 were detected in the produced water samples. The results suggest that the modification of wooden toothpicks with NH2 might offer a significant advancement in the knowledge of cheap substrates that can improve the sensitivity of analysis of NAs in water samples.


Assuntos
Petróleo , Espectrometria de Massas por Ionização por Electrospray , Ácidos Carboxílicos/análise , Ácidos Carboxílicos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Água
5.
Rev Bras Farmacogn ; 31(5): 658-666, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305198

RESUMO

The novel coronavirus SARS-CoV-2 has been affecting the world, causing severe pneumonia and acute respiratory syndrome, leading people to death. Therefore, the search for anti-SARS-CoV-2 compounds is pivotal for public health. Natural products may present sources of bioactive compounds; among them, flavonoids are known in literature for their antiviral activity. Siparuna species are used in Brazilian folk medicine for the treatment of colds and flu. This work describes the isolation of 3,3',4'-tri-O-methyl-quercetin, 3,7,3',4'-tetra-O-methyl-quercetin (retusin), and 3,7-di-O-methyl-kaempferol (kumatakenin) from the dichloromethane extract of leaves of Siparuna cristata (Poepp. & Endl.) A.DC., Siparunaceae, using high-speed countercurrent chromatography in addition to the investigation of their inhibitory effect against SARS-CoV-2 viral replication. Retusin and kumatakenin inhibited SARS-CoV-2 replication in Vero E6 and Calu-3 cells, with a selective index greater than lopinavir/ritonavir and chloroquine, used as control. Flavonoids and their derivatives may stand for target compounds to be tested in future clinical trials to enrich the drug arsenal against coronavirus infections. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s43450-021-00162-5.

6.
Phytochem Anal ; 32(3): 262-282, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32681766

RESUMO

INTRODUCTION: Mass spectrometry in natural products research has been used as a first step to identify possible chemical structures and to guide subsequent efforts to isolate novel compounds. Preparations of Ampelozizyphus amazonicus Ducke (AA) are known for their high content of saponins, especially dammarane-type triterpenoid aglycones. In the Amazon, where it is known as "saracura-mirá", roots and bark are widely used for the treatment and prevention of malaria, while the wood is discarded. The extract prepared from the wood is also saponin-rich, but its exact chemical composition has not been described. OBJECTIVE: This study provides information on the chemical profiling and tentative structural identification of the major compounds (saponins) present in aqueous and ethanol extracts of bark and wood of AA by mass spectrometry. METHODS: The strategy used to identify compounds present in all samples was ultra-high-performance liquid chromatography with an ultraviolet detector coupled to tandem mass spectrometry (UHPLC-UV-MS/MS) for the analysis of fragmentation patterns through product ion scan using MZmine 2 software. Also, direct sample injection and electrospray ionisation combined with high-resolution mass spectrometry (DI-ESI-HRMS) measurements were performed. RESULTS: The extracts showed chemical similarity, and 95 saponins were tentatively identified in AA wood and bark, including 73 which are described for the first time as tentative structures for this plant species. CONCLUSION: This research describes a useful method for the fast and simultaneous tentative identification of major saponins in AA, contributing to the study of the chemical properties of this genus and family. Furthermore, it demonstrates the importance of the qualitative dereplication process, allowing a straightforward way to propose the tentative identification of compounds.


Assuntos
Saponinas , Cromatografia Líquida de Alta Pressão , Casca de Planta , Extratos Vegetais , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Madeira
7.
Anal Bioanal Chem ; 412(22): 5389-5396, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32556565

RESUMO

A method named imprint paper spray ionization mass spectrometry (imprint-PSI-MS) has been developed and employed for the determination of pungency of peppers. A pepper fruit was cut into a triangular shape, deposited onto a triangular paper, and compressed by a homemade press tool aiming to imprint and transfer the pepper constituents onto the paper surface. Subsequently, the triangular paper was submitted to conventional PSI-MS analysis. Twelve peppers were analyzed, ranging from highly pungent to lowly pungent taste. Pepper pungency values from the Scoville scale (in Scoville heat units, SHU) were compared with the ion intensities of the capsaicin and dihydrocapsaicin compounds obtained from the imprint-PSI-MS analysis, and a correlation coefficient of 0.97 was achieved. In addition, the ion intensities of a sugar compound were monitored in all peppers, and the results were compared with the Scoville scale. Low sugar ion intensities were detected in pungent peppers, while high ion intensities were achieved in low-pungent peppers, suggesting that the pepper pungency may be determined by inversely relating pungency to sugar contents. This work demonstrates the utility of the imprint-PSI-MS method to perform rapid qualitative analyses of peppers and estimate the pungency by monitoring the pepper metabolites. Graphical abstract.


Assuntos
Capsicum/química , Espectrometria de Massas/métodos , Papel , Paladar , Capsaicina/análogos & derivados , Capsicum/classificação , Humanos , Especificidade da Espécie
8.
J Proteomics ; 222: 103792, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32335295

RESUMO

Oleic acid (OA) and cis-9, trans-11 conjugated linoleic acid (c9t11-CLA) are fatty acids found in beef with beneficial effects in human health. This study investigated differentially abundant proteins (DAPs) in skeletal muscle of bovines with extreme values of OA, and c9t11-CLA. For each one of the fatty acids, twenty muscle samples were divided into two groups (N = 10_High; N = 10_Low) and analyzed by high definition mass spectrometry. We identified 103 and 133 DAPs between the groups for each fatty acid. We found 64 and 45 up-regulated and 39 and 68 down-regulated proteins for OA and c9t11-CLA, respectively. Comparative analysis between proteomic and transcriptomic data revealed eight and ten genes with a consistent between mRNA expression levels and protein abundance for OA and c9t11-CLA, respectively. Unconventional myosin-Id (MYO1D), mineralocorticoid receptor (NR3C2), geranylgeranyl transferase type-2 subunit-alpha (RABGGTA), and uveal autoantigen with coiled-coil domains and ankyrin repeats (UACA) were found as putative candidate proteins for OA content. Fatty acid synthase (FASN), tubulin alpha-4A chain (TUBA4A), vinculin (VCL), NADH dehydrogenase 1 alpha subcomplex 5 (NDUFA5), and prefoldin subunit 6 (PFDN6) for c9t11-CLA. Our findings contribute to a deeper understanding of the molecular mechanisms behind the regulation of the OA and c9t11-CLA content in cattle skeletal muscle. SIGNIFICANCE: Questions about the association between meat intake and disease incidence in humans has driven animal scientist to pursue a better understanding of the biological processes associated with differences in the intramuscular fat composition. The beneficial effects of oleic acid and conjugated linoleic acid in human health have been demonstrated by improving the immune system and preventing atherosclerosis, different types of cancers, hypertension, and diabetes. Previous genome-wide association and gene expression studies identified genomic regions and differentially expressed genes associated with the fatty acid profile in skeletal muscle. In this work, differences were evaluated at the protein level. The use of a label-free quantitative proteomic approach, compared with muscle transcriptome results obtained by RNA-sequencing, allowed us to earn new insights into the variability in fatty acid deposition in skeletal muscle of farm animals. This study opens new avenues to explore the effect of the fatty acids in the skeletal muscle of livestock animals, which is associated with nutritional values of the meat, and perhaps to understand the mechanisms correlated with metabolic diseases in other species.


Assuntos
Ácidos Linoleicos Conjugados , Animais , Bovinos , Ácidos Graxos , Estudo de Associação Genômica Ampla , Músculo Esquelético , Ácido Oleico , Proteoma , Proteômica
9.
Front Vet Sci ; 7: 606872, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33490134

RESUMO

Pharmacokinetic parameters and efficacy prediction indexes (Cmax/MIC90 and AUC0-24/MIC90) of an enrofloxacin hydrochloride (ENR-HCl) veterinary product soluble in water were determined in healthy broiler chickens of both sexes after a single oral dose of ENR-HCl (equivalent to 10 mg ENR base/kg bw). Monte Carlo simulations targeting Cmax/MIC90 = 10 and AUC0-24/MIC90 =125 were also performed based on a set of MIC (minimum inhibitory concentration) values of bacterial strains that induce common clinical diseases in broiler chickens and that showed to be susceptible to ENR-HCl. Plasma concentrations of ENR and its main metabolite ciprofloxacin (CIP) were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Plasma concentration-time curves were found to fit a non-compartmental open model. The ratio of the area under the plasma concentration-time curve (AUC) of CIP/ENR was 4.91%. Maximum plasma concentrations of 1.35 ± 0.15 µg/mL for ENR-HCl and 0.09 ± 0.01 µg/mL for CIP were reached at 4.00 ± 0.00 h and 3.44 ± 1.01 h, respectively. Areas under the plasma vs. time concentration curve in 24 h (AUC0-24) were 18.91 ± 1.91 h × µg/mL and 1.19 ± 0.12 h × µg/mL for ENR-HCl and CIP, respectively. Using a microbroth dilution method, the minimum inhibitory concentration (MIC90) values were determined for ENR-HCl for 10 bacterial strains (Mycoplasma gallisepticum, Mycoplasma synoviae, Avibacterium paragallinarum, Clostridium perfringens, Escherichia coli, Pseudomonas aeruginosa, Salmonella ser. Enteritidis, Salmonella ser. Gallinarum, Salmonella ser. Pullorum, and Salmonella ser. Typhimurium), which are the most common causes of infectious clinical diseases in broiler chickens. In summary, the PK/PD ratios and Monte Carlo simulation were carried out for ENR-HCl in poultry, which due to its solubility was administered in drinking water. The PK/PD efficacy prediction indexes and Monte Carlo simulations indicated that the ENR-HCl oral dose used in this study is useful for bacterial infections in treating C. perfringens (Gram-positive), E. coli and S. ser. Enteritidis (Gram-negative) and M. gallisepticum bacteria responsible for systemic infections in poultry, predicting a success rate of 100% when MIC ≤ 0.06 µg/mL for E. coli and S. ser. Enteritidis and MIC ≤ 0.1 µg/mL for M. gallisepticum. For C. perfringens, the success rate was 98.26% for MIC ≤ 0.12. However, clinical trials are needed to confirm this recommendation.

10.
Data Brief ; 19: 1314-1317, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30229007

RESUMO

The proteomic data presented in this article are associated with the research article entitled "Longissimus dorsi muscle label-free quantitative proteomic reveals biological mechanisms associated with intramuscular fat deposition" published in Journal of Proteomics [1]. In this article, we characterized the proteomic profile of bovine Longissimus dorsi muscle from Nelore steers and identified differentially abundant proteins associated with the intramuscular fat (IMF) content. An integrated transcriptome-assisted label-free quantitative proteomic approach by High Definition Mass Spectrometry (HDMSE) was employed to identify and quantify the proteins. A functional enrichment analysis using the differentially abundant proteins list was performed to understand the biological processes involved in IMF deposition. Moreover, to explore and clarify the biological mechanisms that influence IMF content, the mRNA data for the same trait from Cesar and collaborators [2] obtained by RNA-sequencing technology was compared with proteomic data. The mRNA data is deposited in the European Nucleotide Archive (ENA) repository (EMBL-EBI), under accession PRJEB13188.

11.
J Proteomics ; 179: 30-41, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29510239

RESUMO

The pathways involved in intramuscular fat (IMF) deposition in Longissimus dorsi muscle were investigated using an integrated transcriptome-assisted label-free quantitative proteomic approach by High Definition Mass Spectrometry. We quantified 1582 proteins, of which 164 were differentially abundant proteins (DAPs, p < 0.05) between animals with high (H) and low (L) genomic estimated breeding values (GEBV) for IMF content. Ingenuity pathway analysis (IPA) revealed that these DAPs were mainly involved in glycolysis metabolism, actin cytoskeleton signaling, cell-cell adherens junction and pathways for MAPK and insulin. A comparative study between transcriptomic (mRNA) and proteomic data showed 17 differentially expressed genes corresponding to DAPs, of which three genes/proteins did not agree on the direction of the fold change between groups. Moreover, we investigated microRNAs data to explain these differences in fold change direction, being able to unravel two of the three unexpected mRNA/protein relationships. Results demonstrated that changes in protein/mRNA levels of sarcomere organization, intracellular signal transduction and regulation of actin cytoskeleton, are involved in IMF deposition. These findings provide a deeper understanding of the highly complex regulatory mechanisms involved in IMF deposition in cattle and indicate target pathways for future studies. SIGNIFICANCE: Intramuscular fat is the amount of fat deposited inside muscle and plays an important role in human health and meat quality attributes, influencing energy metabolism of skeletal muscle, as well as, tenderness, flavor, and juiciness of beef. We performed for the first time the utilization of integrated transcriptome-assisted label-free quantitative proteomic approach using High Definition Mass Spectrometry for characterization of the changes in the proteomic profile of the Longissimus dorsi muscle associated with intramuscular fat deposition in cattle. Furthermore, we compared the muscle proteome with the muscle transcriptome (mRNA and microRNAs), obtained by RNA-sequencing, to better understand the relationship between expression of mRNAs and proteins and to unravel essential biological mechanisms involved in bovine skeletal muscle IMF deposition.


Assuntos
Tecido Adiposo/metabolismo , Metabolismo Energético/fisiologia , Músculo Esquelético/metabolismo , Proteoma/metabolismo , Transcriptoma/fisiologia , Animais , Cruzamento , Bovinos , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Análise de Sequência de RNA
12.
Reproduction ; 154(6): 881-893, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28971896

RESUMO

The influence of in vitro maturation (IVM) in oocytes is still not totally understood. The aim of this study was to determine the influence of IVM on the metabolism and homeostasis of bovine cumulus-oocyte complexes. In the present study, we demonstrated that IVM leads to accumulation of neutral lipids associated with differential levels of the mono-, di- and triacylglycerols in both cumulus cells and oocytes. We observed that in vitro-matured oocytes exhibited decreased glutathione and reactive oxygen species levels and a lower ATP/ADP ratio when compared to in vivo-matured oocytes, with no significant differences in metabolism and stress-related mRNA or miRNA levels. Moreover, in addition to an increase in lipids in in vitro-matured cumulus cells, fatty acid synthesis and accumulation as well as glycolysis pathway genes were upregulated, whereas those affiliated with the ß-oxidation pathway were decreased. Our gene expression data in cumulus cells suggest the disruption of endoplasmic reticulum stress, apoptosis and cellular stress response pathways during IVM. Furthermore, a total of 19 miRNAs were significantly altered by the maturation process in cumulus cells. These results indicate some new negative influences of the in vitro system in cumulus-oocyte complexes, demonstrating the occurrence of functional disruption in lipid metabolism and stress pathways and showing evidences suggesting the occurrence of altered mitochondrial activity and energy metabolism during IVM, with a massive dysregulation of the corresponding transcripts in the surrounding cumulus cells.


Assuntos
Células do Cúmulo/metabolismo , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/metabolismo , Estresse Oxidativo , Animais , Bovinos , Células Cultivadas , Células do Cúmulo/citologia , Metabolismo Energético , Feminino , Oócitos/citologia , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
14.
PLoS One ; 10(5): e0126585, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26010907

RESUMO

Golden retriever muscular dystrophy (GRMD) provides the best animal model for characterizing the disease progress of the human disorder, Duchenne muscular dystrophy (DMD). The purpose of this study was to determine steroid hormone concentration profiles in healthy golden retriever dogs (control group - CtGR) versus GRMD-gene carrier (CaGR) and affected female dogs (AfCR). Therefore, a sensitive and specific analytical method was developed and validated to determine the estradiol, progesterone, cortisol, and testosterone levels in the canine serum by isotope dilution liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). To more accurately understand the dynamic nature of the serum steroid profile, the fluctuating levels of these four steroid hormones over the estrous cycle were compared across the three experimental groups using a multivariate statistical analysis. The concentration profiles of estradiol, cortisol, progesterone, and testosterone revealed a characteristic pattern for each studied group at each specific estrous phase. Additionally, several important changes in the serum concentrations of cortisol and estradiol in the CaGR and AfCR groups seem to be correlated with the status and progression of the muscular dystrophy. A comprehensive and quantitative monitoring of steroid profiles throughout the estrous cycle of normal and GRMD dogs were achieved. Significant differences in these profiles were observed between GRMD and healthy animals, most notably for estradiol. These findings contribute to a better understanding of both dog reproduction and the muscular dystrophy pathology. Our data open new venues for hormonal behavior studies in dystrophinopathies and that may affect the quality of life of DMD patients.


Assuntos
Doenças do Cão/sangue , Doenças Genéticas Ligadas ao Cromossomo X/sangue , Hormônios/sangue , Marcação por Isótopo/métodos , Distrofia Muscular Animal/sangue , Esteroides/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida , Análise Discriminante , Cães , Feminino , Análise de Componente Principal , Reprodutibilidade dos Testes
15.
Endocrinology ; 155(12): 5011-23, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25299569

RESUMO

The plasma levels of corticosteroids and sex steroids during pregnancy are key indicators of mammalian placental function and the onset of parturition. Steroid hormones are believed to be disturbed in pregnancies produced using assisted reproductive technologies (ARTs) due to placental dysfunction and the frequently observed lack of parturition signals. To elucidate the plasma steroid dynamics, a liquid chromatography-tandem mass spectrometry method was developed and used to determine the levels of corticosteroids (corticosterone, 11-deoxycortisol, and cortisol) and their direct precursors (progesterone and 17α-OH-progesterone) as well as sex steroids (androstenedione, estrone, estrone sulfate, testosterone, and 17ß-estradiol) in bovine plasma. The levels of these 10 steroids in recipient cows carrying naturally conceived (control), in vitro fertilized (IVF), or cloned (somatic cell nuclear transfer) conceptuses were compared during late-term pregnancy (30 days before parturition), during near-term pregnancy (1 day before parturition), and on the day of parturition (day 0). Significant differences were observed among the corticosteroid levels: higher levels of corticosterone, 11-deoxycortisol, and cortisol were detected in cloned pregnancies at day 30; lower levels of corticosterone were observed in ART-derived pregnancies at days 1 and 0; and estrone and estradiol levels were higher in IVF pregnancies throughout the final development. These results suggested an upregulation of the P450C11 and P450C21 enzymes 30 days before parturition in somatic cell nuclear transfer pregnancies and an overactivation of the aromatase enzyme in IVF pregnancies. Taken together, the monitoring of multiple steroid hormones revealed that the pregnancies obtained using ART exhibited plasma steroid concentration dynamics compatible with the dysregulation of steroidogenic tissues.


Assuntos
Corticosteroides/sangue , Análise Química do Sangue/métodos , Fertilização in vitro , Hormônios Esteroides Gonadais/sangue , Técnicas de Transferência Nuclear , Animais , Bovinos , Cromatografia Líquida , Feminino , Gravidez , Espectrometria de Massas por Ionização por Electrospray
16.
J Agric Food Chem ; 60(45): 11263-7, 2012 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-23113649

RESUMO

Brazil nut oil is one of the important Amazonian natural products in the global market. Despite its health benefits and applications in food and cosmetic industries, authentication and quality control of the oil are far from satisfactory. Several samples of Amazonian Brazil nut oil (authentic oils of different geographic origins, commercial oils, and oils adulterated with soybean oil) were evaluated by easy ambient sonic-spray ionization mass spectrometry (EASI-MS). The samples were characterized on the basis of triacylglycerol profiles, and their major ions were subjected to chemometric treatment (principal component analysis). The ambient mass spectrometry analysis and the set of major ions allowed the characterization of authentic oils, commercial oils, and adulterated oils (5% soybean oil) in a few minutes and without sample preparation. Therefore, it is shown that quality control of Amazonian vegetable oils can be readily accomplished by EASI-MS.


Assuntos
Bertholletia/química , Óleos de Plantas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Triglicerídeos/química , Controle de Qualidade , Espectrometria de Massas por Ionização por Electrospray/instrumentação
17.
J Mass Spectrom ; 47(1): 1-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22282083

RESUMO

Venturi easy ambient sonic spray ionization mass spectrometry in both its liquid (V(L) -EASI-MS) and solid sample modes (V(S) -EASI-MS) is shown to provide nearly immediate and secure typification of woods, as demonstrated for Mahogany, an endangered and most valuable type of tropical wood. This reddish wood displays unique phytochemical markers (phragmalin-type limonoids) which are rapidly detected from the wood surface by V(S) -EASI-MS or from a simple methanol extract of a tiny wood chip by V(L) -EASI-MS. Unique profiles were obtained for Mahogany (Swietenia macrophylla) whereas genuine samples of six other similar types of woods, which are commonly falsified by artificial coloring and commercialized as Mahogany, display also typical but dissimilar pythochemical profiles as compared to that of the authentic wood. Variable and atypical chemical profiles were observed for artificially colored woods. Secure chemical characterization via V(S) -EASI-MS or V(s) -EASI-MS fingerprints of Mahogany and other types of woods with similar appearance should help to control the illegal logging and trade of this and other endangered woods and their falsification, and to create certified standards.


Assuntos
Meliaceae/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Madeira/classificação , Fracionamento Químico , Espécies em Perigo de Extinção , Limoninas/análise , Metanol , Árvores , Madeira/análise , Madeira/química
18.
Amino Acids ; 40(1): 197-204, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20512597

RESUMO

Potentially bioactive N-(aminoalkyl)lactamic amino acids and esters were synthesized in satisfactory to good yields by S(N)Ar reactions of aromatic acids with N-(3-aminopropyl)lactams followed by esterification with tertiary amino alcohols. The addition-elimination S(N)Ar mechanism was confirmed by NMR and MS measurements.


Assuntos
Ácido 4-Aminobenzoico/síntese química , Aminoácidos/síntese química , Ésteres/síntese química , Ácido 4-Aminobenzoico/química , Aminoácidos/química , Esterificação , Ésteres/química , Estrutura Molecular
19.
Anal Bioanal Chem ; 398(1): 265-94, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20521143

RESUMO

Mass spectrometry has recently undergone a second contemporary revolution with the introduction of a new group of desorption/ionization (DI) techniques known collectively as ambient mass spectrometry. Performed in an open atmosphere directly on samples in their natural environments or matrices, or by using auxiliary surfaces, ambient mass spectrometry (MS) has greatly simplified and increased the speed of MS analysis. Since its debut in 2004 there has been explosive growth in the applications and variants of ambient MS, and a very comprehensive set of techniques based on different desorption and ionization mechanisms is now available. Most types of molecules with a large range of masses and polarities can be ionized with great ease and simplicity with the outstanding combination of the speed, selectivity, and sensitivity of MS detection. This review describes and compares the basis of ionization and the concepts of the most promising ambient MS techniques known to date and illustrates, via typical analytical and bioanalytical applications, how ambient MS is helping to bring MS analysis deeper than ever into the "real world" open atmosphere environment--to wherever MS is needed.


Assuntos
Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Preparações Farmacêuticas/análise , Humanos
20.
Anal Chem ; 82(10): 3990-6, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20394407

RESUMO

An ambient ionization/desorption technique, namely, easy ambient sonic-spray ionization mass spectrometry (EASI), has been applied to crude oil samples. From a single droplet of the sample placed on an inert surface, EASI(+/-) is shown to promote efficient desorption and ionization of a myriad of polar components via the action of its cloud of very minute supersonic bipolar charged droplets. The gaseous [M + H](+) and [M - H](-) ions concurrently formed by EASI(+/-) were analyzed by Fourier transform mass spectrometry (FT-ICR MS), and a total of approximately 6000 acidic and basic components have been attributed. EASI(+/-) FT-ICR MS of crude oils is show to be almost as fast as ESI(+)/ESI(-) FT-ICR MS, providing similar compositional information of polar components and spectral quality comparable to that of a commercial nonochip-based robotic ESI device. EASI(+/-) requires no sample workup thus eliminating risks of contamination during sample manipulation and memory effects because of carry over in pumping ESI lines. More importantly, EASI(+/-) is a voltage-free ionization technique therefore eliminating risks of redox processes or duality of ionization mechanisms that can be observed in voltage-assisted processes. Data visualization via typical petroleomic plots confirms the similarity of the compositional information provided by EASI(+/-) compared to ESI(+)/ESI(-). The ambient EASI(+/-) FT-ICR MS method requires no voltage switching in changing the ion polarity mode, offering a workup, heating and voltage-free protocol for petroleomic studies performed at open atmosphere directly on the undisturbed crude oil sample.

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