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1.
J Clin Med ; 11(19)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36233653

RESUMO

BACKGROUND: The treatment of ovarian carcinomatosis with cytoreductive surgery and HIPEC is still controversial. The effect and pharmacokinetics of the chemotherapeutics used (especially taxanes) are currently under consideration. METHODS: A phase II, simple blind and randomized controlled trial (NTC02739698) was performed. The trial included 32 patients with primary or recurrent ovarian carcinomatosis undergoing cytoreductive surgery (CRS) and intraoperative intraperitoneal chemotherapy with paclitaxel (PTX): 16 in hyperthermic (42-43 °C) and 16 in normothermic (37 °C) conditions. Tissue, serum and plasma samples were taken in every patient before and after intraperitoneal chemotherapy to measure the concentration of PTX. To analyze the immunohistochemical profile of p53, p27, p21, ki67, PCNA and caspase-3 and the pathological response, a scale of intensity and percentage of expression and a grouped Miller and Payne system were used, respectively. Perioperative characteristics and morbi-mortality were also analyzed. RESULTS: The main characteristics of patients, surgical morbidity, hemotoxicity and nephrotoxicity were similar in both groups. The concentration of paclitaxel in the tissue was higher than that observed in plasma and serum, although no statistically significant differences were found between the two groups. No statistically significant association regarding pathological response and apoptosis (caspase-3) between both groups was proved. There were no statistically significant differences between the normothermic and the hyperthermic group for pathological response and apoptosis. CONCLUSIONS: The use of intraperitoneal PTX has proven adequate pharmacokinetics with reduction of cell cycle and proliferation markers globally without finding statistically significant differences between its administration under hyperthermia versus normothermia conditions.

2.
J Sep Sci ; 45(1): 166-171, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34403200

RESUMO

A wide number of analytical terms have been applied erroneously for many years by analytical chemists, and they apply at present yet, by considering the time makes their use correct. The question is, may precedents validate the present use of incorrect scientific terms? Misused terms are found along the analytical process, starting with giving the name of the sample to the exiguous fraction of the original sample that reaches the detector or the high-resolution equipment after sample pretreatment and sample preparation. All the steps of the analytical process are considered in this article, with special emphasis on sample preparation and, within this, on the use of ultrasound, mainly for assisting extraction more unequivocally named as leaching or lixiviation. A call of attention in this respect is considered by the author to be of help to the analytical community.

3.
Nutrients ; 13(11)2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34836003

RESUMO

The most representative indicator of vitamin D status in clinical practice is 25(OH)D3, but new biomarkers could improve the assessment of vitamin D status and metabolism. The objective of this study is to investigate the association of serum vitamin D metabolites and vitamin D metabolite ratios (VMRs) with potentially influential factors in premenopausal women. This is a cross-sectional study based on 1422 women, aged 39-50, recruited from a Madrid Medical Diagnostic Center. Participants answered an epidemiological and a food frequency questionnaire. Serum vitamin D metabolites were determined using an SPE-LC-MS/MS platform. The association between participant's characteristics, vitamin D metabolites, and VMRs was quantified by multiple linear regression models. Mean 25(OH)D3 concentration was 49.2 + 18.9 nmol/L, with greater deficits among obese, nulliparous, dark-skinned women, and with less sun exposure. A lower R2 ratio (1,25(OH)2D3/25(OH)D3) and a higher R4 (24,25(OH)2D3/1,25(OH)2D3) were observed in nulliparous women, with high sun exposure, and those with low caloric intake or high consumption of calcium, vitamin D supplements, or alcohol. Nulliparous women had lower R1 (25(OH)D3/Vit D3) and R3 (24,25(OH)2D3/25(OH)D3), and older women showed lower R3 and R4. Vitamin D status modified the association of the VMRs with seasons. VMRs can be complementary indicators of vitamin D status and its endogenous metabolism, and reveal the influence of certain individual characteristics on the expression of hydroxylase enzymes.


Assuntos
Metaboloma , Pré-Menopausa/sangue , Vitamina D/sangue , Adulto , Feminino , Humanos , Pessoa de Meia-Idade
4.
Mol Nutr Food Res ; 63(9): e1800864, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30730089

RESUMO

SCOPE: Wine has shown anticarcinogenic benefits in hepatocarcinoma and polyphenols seem to be responsible for these effects. Wine lees are the sediments produced during fermentation and they endow wine with organoleptic and physicochemical properties. However, the anticarcinogenic role of these compounds is still unknown. Thus, the purpose of this work is to determine the phytochemical profiles of wine lees and then to analyze their anticarcinogenic effect and DNA methylation on a model of hepatocarcinogenesis. METHODS AND RESULTS: The phytochemical composition of lees is determined by the Folin-Ciocalteu method and high-performance liquid chromatography. An in vivo study using a diethyl nitrosamine-hepatocarcinogenesis-induced model is performed to investigate the hepatoprotective properties of different doses of wine lees. For the DNA methylation analysis, a bisulfite-based method is used. Both types of lees mostly contain pyrogallol, gallic, and syringic acid with a high content of catechins in red lees. The carcinogen hypermethylates the Alu-M2 repetitive sequence and white lees decreases the hypermethylation at all tested concentrations. Low concentration of red and white lees and high concentration of white lees significantly improve the hepatocellular architecture and decrease the mitotic index in the murine model. CONCLUSION: These findings suggest that wine lees are promising agents for chemoprevention of hepatocarcinoma.


Assuntos
Anticarcinógenos/farmacologia , Neoplasias Hepáticas Experimentais/prevenção & controle , Fígado/efeitos dos fármacos , Vinho , Elementos Alu , Animais , Anticarcinógenos/química , Peso Corporal/efeitos dos fármacos , Catecóis/análise , Metilação de DNA/efeitos dos fármacos , Dietilnitrosamina/toxicidade , Fermentação , Ácido Gálico/análogos & derivados , Ácido Gálico/análise , Fígado/patologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Pirogalol/análise , Ratos Sprague-Dawley , Vinho/análise
6.
PLoS One ; 12(3): e0172908, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28253357

RESUMO

Biological treatments to degrade cyanide are a powerful technology for cyanide removal from industrial wastewaters. It has been previously demonstrated that the alkaliphilic bacterium Pseudomonas pseudoalcaligenes CECT5344 is able to use free cyanide and several metal-cyanide complexes as the sole nitrogen source. In this work, the strain CECT5344 has been used for detoxification of the different chemical forms of cyanide that are present in alkaline wastewaters from the jewelry industry. This liquid residue also contains large concentrations of metals like iron, copper and zinc, making this wastewater even more toxic. To elucidate the molecular mechanisms involved in the bioremediation process, a quantitative proteomic analysis by LC-MS/MS has been carried out in P. pseudoalcaligenes CECT5344 cells grown with the jewelry residue as sole nitrogen source. Different proteins related to cyanide and cyanate assimilation, as well as other proteins involved in transport and resistance to metals were induced by the cyanide-containing jewelry residue. GntR-like regulatory proteins were also induced by this industrial residue and mutational analysis revealed that GntR-like regulatory proteins may play a role in the regulation of cyanide assimilation in P. pseudoalcaligenes CECT5344. The strain CECT5344 has been used in a batch reactor to remove at pH 9 the different forms of cyanide present in industrial wastewaters from the jewelry industry (0.3 g/L, ca. 12 mM total cyanide, including both free cyanide and metal-cyanide complexes). This is the first report describing the biological removal at alkaline pH of such as elevated concentration of cyanide present in a heterogeneous mixture from an industrial source.


Assuntos
Proteínas de Bactérias/metabolismo , Cromatografia Líquida/métodos , Cianetos/toxicidade , Proteômica , Pseudomonas pseudoalcaligenes/efeitos dos fármacos , Espectrometria de Massas em Tandem/métodos , Águas Residuárias/química , Biodegradação Ambiental , Reatores Biológicos , Genes Bacterianos , Pseudomonas pseudoalcaligenes/genética , Pseudomonas pseudoalcaligenes/metabolismo
7.
Talanta ; 162: 24-31, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27837824

RESUMO

Oleocanthal and oleacein, two key secoiridoid derivatives present in virgin olive oil (VOO), are gaining clinical and nutritional interest thanks to their proved bioactivity; therefore, the determination of both phenols is a growing demanded application to increase the value of VOO. The main problem of previously reported liquid chromatography-based methods for oleocanthal and oleacein measurement is their interaction with water or other polar solvents such as methanol to promote the formation of hemiacetal or acetal derivatives. This interaction can occur during either sample extraction, basically liquid-liquid extraction, and/or chromatographic separation. The aim of this research was to evaluate the suitability of LC-MS/MS for absolute quantitation of oleocanthal and oleacein in VOO. For this purpose, both liquid-liquid extraction and chromatographic separation were studied as potential promoters of acetals and hemiacetals formation from oleocanthal and/or oleacein. The results showed that the use of methanol-water solutions for phenols extraction was not influential on the formation of these artifacts. Acetals and hemiacetals from oleocanthal and/or oleacein were only detected at very low concentrations when methanol gradients under acidic conditions were used for chromatographic separation. With this premise, a protocol based on extraction with acetonitrile and a reverse chromatographic gradient with methanol was established to quantify in absolute terms oleocanthal and oleacein in VOO samples. The resulting protocol was applied to three VOO samples characterized by high, medium, and low levels of these two phenols.


Assuntos
Aldeídos/análise , Cromatografia Líquida/métodos , Azeite de Oliva/química , Fenóis/análise , Espectrometria de Massas em Tandem/métodos , Aldeídos/isolamento & purificação , Monoterpenos Ciclopentânicos , Extração Líquido-Líquido/métodos , Metanol/química , Fenóis/isolamento & purificação
8.
Food Chem ; 220: 282-288, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27855900

RESUMO

Hydrolysis of oleuropein, the main phenol in olive (Olea europaea L.) leaf extracts, to oleuropein aglycon and other subsequent products in the hydrolytic pathway can be catalyzed by different enzymes. Three of the most used hydrolases were assayed to catalyze the process, and ß-glucosidase from Aspergillus niger was selected. Acceleration of the enzymatic hydrolysis by ultrasound (US) was studied using a Box-Behnken design (duty cycle, amplitude, cycle time) and an oleuropein standard, and the optimum US conditions for achieving maximum yield of oleuropein aglycon were 0.5s/s duty cycle, 50% amplitude and 45s cycle. The method was applied to obtain oleuropein aglycon from commercial and laboratory extracts from olive leaves, which may have a pharmacological use as deduced by its healthy properties. The kinetics of the US-assisted enzymatic hydrolysis was monitored by analysis of the target compounds using liquid chromatography-tandem mass spectrometry.


Assuntos
Iridoides/química , Olea/química , Extratos Vegetais/química , Folhas de Planta/química , Ultrassom , Aspergillus niger/enzimologia , Cromatografia Líquida , Hidrólise , Glucosídeos Iridoides , Espectrometria de Massas em Tandem , beta-Glucosidase/metabolismo
9.
J Pharm Pharmacol ; 68(10): 1249-67, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27464836

RESUMO

OBJECTIVES: The main aim of this review was to develop a critical discussion of the key role ultrasound (US) can play on the production of active pharmaceutical ingredients (APIs) by discussing the versatile effect this type of energy produces. METHODS: The different crystallization techniques that can be assisted and improved by US are discussed in the light of the available US devices and the effect pursued by application of US energy. Simple and complex analytical methods to monitor API changes are also discussed. KEY FINDINGS: The countless achievements of API US-assisted production are summarized in a table, and outstanding effects such as narrower particle size distribution; decreased particle size, induction time, metastable zone and supersaturation levels; or a solubility increase are critically discussed. CONCLUSIONS: The indisputable advantages of sonocrystallization over other ways of API production have been supported on multiple examples, and pending goals in this field (clarify the effect of US frequency on crystallization, know the mechanism of sonocrystallization, determine potential degradation owing to US energy, avoid calculation of the process yield by determining the concentration of the target drug remaining in the solution, etc.) should be achieved.


Assuntos
Preparações Farmacêuticas/química , Tecnologia Farmacêutica/métodos , Cristalização/métodos , Tamanho da Partícula , Solubilidade , Ultrassom/métodos
11.
Talanta ; 144: 522-8, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26452857

RESUMO

A comparative study of methods for ultrasound-assisted extraction (USAE), microwave-assisted extraction (MAE) and superheated liquid extraction (SHLE) of compounds from citrus has been performed. The suited conditions for each method were evaluated to maximize the concentration of 10 representative compounds (sugars, carboxylic acids, phenolic acids and flavonoids) by a desirability function approach based on the chromatographic peaks obtained by LC-DAD. Extracts obtained under the suited conditions were analyzed by LC-QTOF MS/MS. The ANOVA on the molecular entities showed 232 significant entities (p<0.01), and pairwise comparison revealed that USAE and MAE methods are the most similar (50 different entities), and USAE and SHLE the most dissimilar (224 different entities). A discrimination test by PCA showed a clear discrimination among the extraction methods, explaining 78.51% of the total variability. Similarities in the abundance of the monitored compounds was tested by ANOVA showing that the extraction of carboxylic acids (malic and citric acids) was equal by all methods; while for each of the other eight compounds, at least one extraction method is different from the others. Under the evaluated conditions the SHLE method is the less favorable to extract metabolites from citrus, being the best the USAE method.


Assuntos
Citrus/química , Frutas/química , Extratos Vegetais/análise , Ondas Ultrassônicas , Cromatografia Líquida , Ácido Cítrico/análise , Flavonoides/análise , Glucosídeos/análise , Malatos/análise , Micro-Ondas , Sacarose/análise , Espectrometria de Massas em Tandem/métodos
12.
J Sci Food Agric ; 95(14): 2892-900, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25452231

RESUMO

BACKGROUND: Recent technological advances to improve the quality of virgin olive oil (VOO) have been focused on olive breeding programs by selecting outstanding cultivars and target progenies. Fatty acid (FA) composition, with special emphasis on oleic acid (C18:1) and palmitic acid (C16:0), is one of the most critical quality factors to be evaluated in VOO. For this reason, the profile of FAs is frequently used as a decision tool in olive breeding programs. RESULTS: A method based on gas chromatography with flame ionization detection (GC-FID) was used to study the influence of genotype on the concentration of ten of the most important FAs in VOOs from target crosses Arbequina × Arbosana, Picual × Koroneiki and Sikitita × Arbosana and their corresponding genitors Arbequina, Arbosana, Koroneiki, Picual and Sikitita. For this purpose, a targeted approach was selected for determination of esterified FAs (EFAs) and non-esterified FAs (NEFAs) in a dual analysis by the same chromatographic method. A Pearson analysis revealed correlations between pairs of FAs, which allowed detecting metabolic connections through desaturation and elongation enzymes. An ANOVA test (with P < 0.01) led to identification of C16:0 EFA, C16:1 EFA and C18:1 EFA and also C16:1 NEFA and C18:0 NEFA as the FAs more influenced by cross breeding. Statistical analysis was carried out by unsupervised analysis using principal component analysis (PCA) and cluster analysis (CA) to look for variability sources. CONCLUSION: Crosses with a common genitor (Arbequina × Arbosana and Sikitita × Arbosana) were partially overlapped in the PCAs using the profile of FAs. The CA results revealed clear differences between Sikitita × Arbosana and Picual × Koroneiki crosses in the composition of the most significant FAs, while Arbequina × Arbosana was not properly discriminated from the other crosses.


Assuntos
Ácidos Graxos/análise , Genótipo , Olea/química , Azeite de Oliva/química , Melhoramento Vegetal , Cruzamento , Cromatografia Gasosa , Ácidos Graxos/genética , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/genética , Ionização de Chama , Humanos , Olea/genética , Ácido Oleico/análise , Ácido Oleico/genética , Ácido Palmítico/análise , Especificidade da Espécie
13.
J Agric Food Chem ; 63(2): 692-9, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25541637

RESUMO

Discrimination among the types of feeding regimes for Iberian pigs is currently a highly demanded challenge by the Iberian pig sector. In the present research, discrimination among feeding regimes has been achieved by the combination of two analytical methods (based on FAMEs analysis by GC-FID and determination of δ(13)C by IRMS) previously used independently without success. In the present study, 80 samples of adipose tissue from Iberian pigs subjected to four different feedings were analyzed. The study of the variables more influenced by the feeding regime has allowed us to configure panels of markers with predictive power for the studied feedings by multivariate ROC analysis. The results provided values of specificity and sensitivity higher than 85% in most cases. The statistical combination of results from different analytical methods could be the key to develop models for the correct discrimination of Iberian pigs according to the feeding regime.


Assuntos
Ração Animal/análise , Ácidos Graxos/química , Gordura Subcutânea/química , Suínos/metabolismo , Animais , Isótopos de Carbono/química , Isótopos de Carbono/metabolismo , Ácidos Graxos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Gordura Subcutânea/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-25308544

RESUMO

Olive oil is an integral ingredient of the "Mediterranean diet". The olive oil industry generates large quantities of a by-product called "alperujo" (AL) during the two-phase centrifugation system developed in the early nineties. AL could be a potent exploitable source of natural phenolic antioxidants. Our results showed that AL and its distinctive phenols hydroxytyrosol, tyrosol and verbascoside were not genotoxic in the Somatic Mutation and Recombination Test (SMART) of Drosophila melanogaster and exerted antigenotoxic activity against DNA oxidative damage generated by hydrogen peroxide (H2O2). Alperujo and hydroxytyrosol also exhibited notable antiproliferative and caspase 3-dependent proapoptotic effects toward the human tumoral cell line HL60. AL can provide a cheap and efficient source of chemopreventive phenolic compounds with strong antioxidant properties, becoming a promising and potent therapeutic drug in the future.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Dano ao DNA , Glucosídeos/farmacologia , Fenóis/farmacologia , Álcool Feniletílico/análogos & derivados , Óleos de Plantas/química , Animais , Antioxidantes/química , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Glucosídeos/química , Células HL-60 , Humanos , Peróxido de Hidrogênio/farmacologia , Azeite de Oliva , Oxidantes/farmacologia , Fenóis/química , Álcool Feniletílico/química , Álcool Feniletílico/farmacologia
15.
J Sci Food Agric ; 94(15): 3100-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24633600

RESUMO

BACKGROUND: The growing demand for high-quality virgin olive oils (VOOs) has increased the interest in olive breeding programs. Cross-breeding is considered, within these programs, the best strategy to generate new cultivars as an attempt to improve the present cultivars. In this research, the phenolic profile of VOOs from target crosses (Arbequina × Arbosana, Picual × Koroneiki and Sikitita × Arbosana) and their corresponding genitors (Arbequina, Arbosana, Koroneiki, Picual and Sikitita) has been evaluated using a targeted metabolomics approach. RESULTS: The phenolic profiles were obtained by liquid chromatographic-hybrid quadrupole time-of-flight mass spectrometric targeted analysis of 37 phenols or compounds involved in the main pathways for their biosynthesis. Statistical multivariate analysis by principal component analysis was applied to study the influence of genotype on phenol composition. Phenolic compounds with the highest contribution to explain the observed variability associated to genotype were identified through fold change algorithms (cut-off > 2.0) and t-test analysis. CONCLUSION: A total of nine phenols (viz. quercetin, ligstroside aglycon (p-HPEA-EA), demethyl oleuropein aglycon, oleuropein aglycon (3,4-DHPEA-EA), hydroxypinoresinol, hydroxytyrosol and phenolic acids such as p-coumaric acid, ferulic acid and protocatechuic acid) contributed to explain the observed variability with 99% confidence (P<0.01).


Assuntos
Hibridização Genética , Espectrometria de Massas/métodos , Olea/genética , Fenóis/análise , Óleos de Plantas/química , Cromatografia Líquida , Genótipo , Metabolômica/métodos , Análise Multivariada , Azeite de Oliva
16.
Genes Nutr ; 9(1): 375, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24338342

RESUMO

Metabolites derived from the polyunsaturated fatty acids (PUFA) may modulate the mesenchymal stromal cell (MSC) differentiation. Such cells can differentiate into different cellular types, including adipocytes and osteoblasts. Aging favors the bone marrow MSC differentiation toward the former, causing a loss of bone density associated with pathologies like osteoporosis. The omega-6 arachidonic acid (AA) favors MSC adipogenesis to a greater extent than omega-3 eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In this work, we study the joint action of both PUFA. Thus, not induced and induced to adipocyte or osteoblast MSC were treated with 20 µM of each PUFA (either AA, AA + DHA or AA + EPA). The expression of osteogenic and adipogenic molecular markers, the alox15b lipoxygenase gene expression and the 5-, 8-, 11-, 12- and 15-hydroxyeicosatetraenoic acids (HETE) derived from the AA metabolism in the culture media were determined. The results show that the adipogenesis induction of AA is not suppressed by the joint presence of EPA and DHA. In fact, both increased the adipogenic effect of AA on MSC differentiated into osteoblasts. The different HETE concentrations increased in cultures supplemented with AA, albeit such concentrations were lower in the cultures induced to differentiate, mainly at day 21 after the induction. Furthermore, the reduction in the HETE concentration was correlated with a higher expression of the alox15b gene. These results highlight the PUFA metabolism differences between uninduced and induced MSC to differentiate into adipocytes and osteoblasts, besides the relevant role of the lipoxygenase gene expression in adipogenesis induction.

17.
Electrophoresis ; 34(19): 2901-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24228265

RESUMO

A targeted approach has been applied to quantitative analysis of eicosanoids derived from omega-6 fatty acids in serum from individuals diagnosed with coronary artery disease (CAD). The target metabolites were series-2 prostaglandins, thromboxane B2, hydroxyeicosatetraenoic acids, and hydroxyoctadecadienoic acids. The method was based on SPELC-MS/MS in selected reaction monitoring mode for highly selective and sensitive determination of the target eicosanoids. The combination of SPE and LC-MS/MS involved the benefits from both direct analysis of serum without a step for protein precipitation and fully automation of the analysis. The method allowed comparison of omega-6-derived eicosanoids in serum from patients diagnosed with CAD and from control individuals. The effect of treatment with aspirin on the profile of the target compounds was evaluated through its incidence on the different pathways. Finally, the serum levels of the target metabolites in patients diagnosed with CAD were also statistically examined according to the severity of the coronary lesion stratified as stable angina, non-ST-elevation acute coronary syndrome, and acute myocardial infarction.


Assuntos
Doença da Artéria Coronariana/sangue , Eicosanoides/sangue , Eicosanoides/metabolismo , Ácidos Graxos Ômega-6/metabolismo , Adulto , Idoso , Cromatografia Líquida/métodos , Estudos de Coortes , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
18.
Talanta ; 105: 429-34, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23598041

RESUMO

A dual method is proposed for the determination of metabolites involved in the shikimate pathway which are biomarkers of the effects of glyphosate action on plants exposed to this herbicide. Extraction of the target metabolites (phenylalanine, tryptophan, tyrosine and shikimic acid) from a wheat model plant was accelerated by ultrasound energy. After centrifugation and micro-filtration, 1 µL of extract was injected into the chromatograph in an isocratic regime for 4 min to determine shikimate by absorption at 254 nm. In the mean time, a 130 µL aliquot of extract was subjected to derivatization with o-phthaldialdehyde and 2-mercaptoethanol for 1 min, the reaction stopped and 1 µL of the solution chromatographied in a gradient regime prior to laser-induced fluorescence detection of the derivatized amino acids. The characterization of the dual method provided limits of detection around 0.03 µg mL(-1) for the aromatic amino acids and 1.52 µg mL(-1) for shikimate, whereas the limits of quantitation ranged between 0.084 and 0.093 µg mL(-1) for amino acids and was of 4.56 µg mL(-1) for shikimate. The suitability of the method was checked by application to Triticum aestivum (wheat) plants grown under controlled conditions, sprayed with different doses of glyphosate and collected at different times after exposition to the herbicide.

19.
J Bone Miner Metab ; 31(4): 455-60, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23536191

RESUMO

The aim of this study was to evaluate the relationship between vitamin E status and osteoporosis in early postmenopausal women. Anthropometric data, osteoporosis risk factors, vitamin E serum levels, bone mineral density (BMD) and other serum parameters which may influence bone mineral density in postmenopausal women were analyzed in a cross-sectional study. The association between osteoporosis and age, age of menopause, body mass index, osteocalcin, calcium, vitamin D, vitamin E (measured as 25 hydroxyvitamin D and as α-tocopherol:lipids ratio, respectively), bone alkaline phosphatase, smoking status, leisure physical activity and alcohol intake were modeled by a multivariate logistic regression and multi-linear regression analysis in 232 early postmenopausal women. A lower vitamin E:lipid ratio was associated with osteoporosis in multivariate logistic regression. In a multivariate linear model with BMD of the lumbar spine as a dependent variable, the vitamin E:lipid ratio was clearly related with BMD of the lumbar spine (F ratio = 6.30, p = 0.002). BMD of the lumbar spine was significantly higher in the highest tertile of the vitamin E:lipid ratio than in the lowest tertile. The mean vitamin E:lipid ratio was significantly lower in osteoporotic postmenopausal women (T score ≤-2.5) (3.0 ± 0.6 µmol/mmol) than normal (neither osteoporotic nor osteopenic) postmenopausal women (T score >-1) (3.5 ± 0.7 µmol/mmol) using multivariable-adjusted BMD. These findings highlight that vitamin E may increase BMD in healthy postmenopausal women.


Assuntos
Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/etiologia , Vitamina E/sangue , Antropometria , Densidade Óssea/fisiologia , Estudos Transversais , Feminino , Colo do Fêmur/patologia , Colo do Fêmur/fisiopatologia , Humanos , Modelos Lineares , Vértebras Lombares/patologia , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Análise Multivariada
20.
Analyst ; 138(7): 2146-55, 2013 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-23435066

RESUMO

An approach for quantitative analysis of two vitamins with different polarities (vitamins D and B9) and their metabolites is presented here. The approach is based on an experimental setup based on hyphenation of an automated workstation for preparation of liquid samples and an LC-MS/MS system with a triple quadrupole mass spectrometer. This configuration enabled development of an orthogonal protocol for sequential SPE retention of analytes with different polarities for subsequent elution and chromatographic separation prior to detection. The resulting method was validated by application to three human biofluids. Estimation of recovery factors in the SPE step led to values from 85.2 to 100% for vitamin D and metabolites and from 93.1 to 100% for vitamin B9 and metabolites (folic acid and folates). The influence of sample matrix variability by analysis of human serum, urine and breast milk was minimized with a complete optimization of the SPE step. The utility of the proposed configuration is shown by the sensitivity and precision of the method, expressed as limits of detection (between 0.2 and 0.30 ng mL(-1) or 4 and 60 pg on-column) and within-laboratory reproducibility (lower than 6.7%, as relative standard deviation). The present application represents an example of determination methods involving targeted analysis of compounds with different polarities using a single aliquot of the sample.


Assuntos
Ácido Fólico/sangue , Leite Humano/química , Espectrometria de Massas em Tandem/métodos , Vitamina D/sangue , Autoanálise , Cromatografia Líquida/métodos , Feminino , Ácido Fólico/isolamento & purificação , Ácido Fólico/urina , Humanos , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Vitamina D/isolamento & purificação , Vitamina D/urina
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