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1.
Food Chem ; 441: 138377, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38219367

RESUMO

Immunomagnetic beads provide novel tools for high-throughput immunoassay techniques. In this study, protein G (PG) was immobilized onto bacterial magentic particles (BMPs) using an additional cysteine residue at the C-terminus. A broad-spectrum monoclonal antibody against glucocorticoids (GCs) was attached to BMPs through PG-Fc interaction, generating BMP-PG-mIgG immunomagentic beads. A sensitive one-step immunoassay was developed for GCs based on combination of BMP-PG-mIgG and dexamethasone-horseradish peroxidase tracer (DMS-HRP). The developed assay exhibited half inhibitory concentrations (IC50) for dexamethasone (DMS), betamethasone (BMS), prednisolone (PNS), hydrocortisone (HCS), beclomethasone (BCMS), cortisone (CS), 6-α-methylprednisone (6-α-MPNS), fludrocortisone acetate (HFCS) of 0.98, 1.49, 2.42, 9.29, 1.63, 6.13, 7.3, and 4.89 ng/mL, respectively. The method showed recoveries ranging rates from 86.5 % to 117 % with a coefficient of variation less than 12.3 % in milk sample, which showed a good correlation with LC-MS/MS. Thus, the proposed assay offers a rapid and broad-spectrum screening tool for simultaneous detection of GCs in milk.


Assuntos
Glucocorticoides , Magnetossomos , Animais , Glucocorticoides/análise , Leite/química , Cromatografia Líquida , Espectrometria de Massas em Tandem , Imunoensaio/métodos , Bactérias , Dexametasona/análise , Separação Imunomagnética/métodos
2.
Anal Bioanal Chem ; 415(16): 3215-3229, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37120618

RESUMO

Reliable data are compulsory to efficiently monitor pollutants in aquatic environments, particularly steroid hormones that can exert harmful effects at challenging analytical levels below the ng L-1. An isotope dilution two-step solid-phase extraction followed by an ultra-performance liquid chromatography separation coupled to tandem mass spectrometry (UPLC-MS/MS) detection method was validated for the quantification of 21 steroid hormones (androgens, estrogens, glucocorticoids, and progestogens) in whole waters. To achieve a realistic and robust assessment of the performances of this method, the validation procedure was conducted using several water samples representative of its intended application. These samples were characterized in terms of concentration of ionic constituents, suspended particulate matter (SPM), and dissolved organic carbon contents (DOC). For estrogens that are part of the European Water Framework Directive Watchlist (17beta-estradiol and estrone), the performances met the European requirements (decision 2015/495/EU) in terms of limit of quantification (LQ) and measurement uncertainty. For 17alpha-ethinylestradiol, the challenging LQ of 0.035 ng L-1 was reached. More generally, for 15 compounds out of 21, the accuracy, evaluated in intermediate precision conditions at concentrations ranging between 0.1 and 10 ng L-1, was found to be within a 35% tolerance. The evaluation of the measurement uncertainty was realized following the Guide to the expression of Uncertainty in Measurement. Finally, a water monitoring survey demonstrated the suitability of the method and pointed out the contamination of Belgium rivers by five estrogens (17alpha-ethinylestradiol, estriol, 17alpha-estradiol, 17beta-estradiol, and estrone) and three glucocorticoids (betamethasone, cortisol, and cortisone) which have been up to now poorly documented in European rivers.


Assuntos
Estrona , Poluentes Químicos da Água , Cromatografia Líquida/métodos , Glucocorticoides/análise , Espectrometria de Massas em Tandem/métodos , Estrogênios/análise , Estradiol/análise , Etinilestradiol , Água/química , Poluentes Químicos da Água/análise
3.
Environ Sci Pollut Res Int ; 30(8): 20765-20774, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36255587

RESUMO

Estrogen, androgen, and glucocorticoid receptors (ER, AR, and GR) agonist activities in river water samples from Chennai and Bangalore (India), Jakarta (Indonesia), and Hanoi (Vietnam) were evaluated using a panel of chemical-activated luciferase gene expression (CALUX) assays and were detected mainly in the dissolved phase. The ER agonist activity levels were 0.011-55 ng estradiol (E2)-equivalent/l, higher than the proposed effect-based trigger (EBT) value of 0.5 ng/l in most of the samples. The AR agonist activity levels were < 2.1-110 ng dihydrotestosterone (DHT)-equivalent/l, and all levels above the limit of quantification exceeded the EBT value of 3.4 ng/l. GR agonist activities were detected in only Bangalore and Hanoi samples at dexamethasone (Dex)-equivalent levels of < 16-150 ng/l and exceeded the EBT value of 100 ng/l in only two Bangalore samples. Major compounds contributing to the ER, AR, and GR agonist activities were identified for water samples from Bangalore and Hanoi, which had substantially higher activities in all assays, by using a combination of fractionation, CALUX measurement, and non-target and target chemical analysis. The results for pooled samples showed that the major ER agonists were the endogenous estrogens E2 and estriol, and the major GR agonists were the synthetic glucocorticoids Dex and clobetasol propionate. The only AR agonist identified in major androgenic water extract fractions was DHT, but several unidentified compounds with the same molecular formulae as endogenous androgens were also found.


Assuntos
Glucocorticoides , Poluentes Químicos da Água , Androgênios/análise , Bioensaio/métodos , Estrogênios/análise , Estrona/análise , Glucocorticoides/análise , Índia , Rios/química , Água/análise , Poluentes Químicos da Água/análise , Indonésia , Vietnã
4.
Artigo em Inglês | MEDLINE | ID: mdl-35301171

RESUMO

BACKGROUND: The long-term sleep state has an important influence on one's physical and mental health. Melatonin (MEL) and cortisol with circadian rhythm are deemed to be potential sleep biomarkers. Considering the rapid metabolism of MEL and cortisol, their main metabolites could be alternative indicators showing higher stability and reliability. However, there is short of research developing the method for simultaneous quantification of MEL, cortisol and their metabolites in hair. OBJECTIVES: This study aimed to develop a method for the simultaneous quantification of F, MEL and their main metabolites (cortisone; N-acetyl-serotonin, NAS; 6-hydroxymelatonin, 6-O-MEL and 6-sulfatoxymelatonin, S-O-MEL) in human hair based on high-performance liquid chromatography tandem mass spectrometry method, and then explore the relationship between the biomarkers' contents and sleep state. METHODS: Analytes were extracted from 20-mg hair in 1 mL methanol at about 27°C, and then analyzed in a mobile phase of 95% methanol and 5% 5 mM ammonium acetate, and identified with an electrospray ionization source in positive ion mode. Hair samples closest to the scalp were collected from 65 undergraduates. Sleep state was measured based on participants' scores of the Pittsburgh Sleep Quality Index, the Epworth Sleepiness Scale and the Morningness/Eveningness Questionnaire. RESULTS: The method showed good linearity with the square of correlation coefficient > 0.99 at the ranges of 0.1-1000 pg/mg for MEL, 0.4-1000 pg/mg for NAS, 1.0-1000 pg/mg for 6-O-MEL, 1.0-1000 pg/mg for S-O-MEL, 0.5-1000 pg/mg for cortisol and 1.0-1000 pg/mg for cortisone. It showed the limit of detection ranged from 0.05 to 0.3 pg/mg and the limit of quantification ranged between 0.1 and 1.0 pg/mg for the six analytes. The inter- and intra-day coefficients of variation were < 20%. The compounds could be detected in natural hair samples except for S-O-MEL. The average concentration was 0.18 pg/mg for MEL, 3.5 pg/mg for NAS, 3.8 pg/mg for 6-O-MEL, 20.0 pg/mg for cortisone and 2.8 pg/mg for cortisol. The population analysis revealed that there was positive association between hair cortisone and sleep quality. CONCLUSIONS: This study had developed an LC-MS/MS method for simultaneous quantification of MEL, NAS, 6-O-MEL, cortisone and cortisol in human hair. Hair cortisone might be a promising biomarker of long-term sleep state.


Assuntos
Glucocorticoides , Melatonina , Cromatografia Líquida/métodos , Glucocorticoides/análise , Cabelo/química , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
5.
Reprod Fertil Dev ; 33(18): 841-854, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34844663

RESUMO

With fewer than 7500 cheetahs remaining in the wild, ex situ cheetah populations serve as an insurance policy against extinction and a resource to study species' biology. This study aimed to identify the age of pubertal onset in ex situ female cheetahs using non-invasive faecal steroid hormone monitoring and body weights. Faecal samples from nine female cheetahs were collected two to three times weekly from 2 to 36months of age and body weights were recorded every 3months. Faecal oestrogen metabolites (FOM) and faecal glucocorticoid metabolites (FGM) were analysed using enzyme immunoassays and samples were categorised into 6-month intervals to compare endocrine characteristics. Faecal hormone and body weight data were analysed using generalised linear mixed models. Age was a significant predictor of mean and baseline FOM concentrations, number of FOM peaks, mean and maximum FOM peak concentrations and the number of cycles. Female cheetahs aged 24-30months exhibited a marked rise in mean FOM concentration and the number of FOM peaks and cycles increased with age until 24-30months. Females attained adult body weight by 21months of age. Mean and baseline FGM concentrations were highest at the 0-6 and 12-18months of age groups and did not follow the same FOM patterns. Based on body weight data, the FOM concentrations and peak patterning, females were considered pubertal from 24 to 30months of age. Characterisation of cheetah puberty has direct and significant implications for the improvement of management and reproductive success of cheetahs under human care. This information is particularly informative for identifying important windows of development, littermate dispersal and breeding introductions.


Assuntos
Peso Corporal/fisiologia , Estrogênios/metabolismo , Fezes/química , Glucocorticoides/análise , Maturidade Sexual/fisiologia , Acinonyx , Animais , Estrogênios/análise , Feminino
6.
Gen Comp Endocrinol ; 299: 113607, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32882210

RESUMO

Pangolins are 'keystone species' driven towards extinction due to a lack of profound awareness and illegal trade. The drivers urge for immediate development in the understanding of demographics and reproductive dynamics of this species. In this study, we developed and validated a quantitative method to measure pangolin fecal extracts using the electrospray (ESI-MS/MS) interface in positive ionization mode. The method aids in the measurement of hormones from the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axis, making it a possibly appropriate technique to understand the cross-talk between the axes. The study aims to measure the relative abundance of adrenal and gonadal hormones such as corticosterone, cortisol, estrone, estradiol-17ß, progesterone, testosterone, and a number of its metabolites. From the dried fecal extract, the principal metabolite identified from the estrogen family was estradiol-17ß, whereas the gestagen family revealed that the pregnane series is predominated in 5α-configuration. On the other hand, epiandrosterone was seen as the dominant form in the male fecal extracts. Additionally, the glucocorticoids are excreted majorly as corticosterone, but traces of cortisol are also present in both the male and female fecal samples. The physiological validation confirmed that the ESI-MS/MS technique is suitable to determine physiologically caused differences in the fecal steroid concentrations. Physiologically, the age structure in pangolin is not responsible for causing differences within gender. However, the results revealed that glucocorticoids might vary between the sexes, i.e., males have a higher relative abundance of glucocorticoids over females. Therefore, our studies show that some of the main adrenal and gonadal metabolites can be predicted by exploiting MS/MS, which can steer research to potentially assess the reproductive status of captive and free-ranging pangolin species.


Assuntos
Espécies em Perigo de Extinção , Fezes/química , Pangolins/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Esteroides/análise , Esteroides/metabolismo , Espectrometria de Massas em Tandem/métodos , Animais , Corticosterona/análise , Corticosterona/metabolismo , Estradiol/análise , Estradiol/metabolismo , Estrogênios/análise , Estrogênios/metabolismo , Estrona/análise , Estrona/metabolismo , Feminino , Glucocorticoides/análise , Glucocorticoides/metabolismo , Hidrocortisona/análise , Hidrocortisona/metabolismo , Masculino , Progesterona/análise , Progesterona/metabolismo , Testosterona/análise
8.
J Steroid Biochem Mol Biol ; 195: 105476, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31561001

RESUMO

The presence of estrogens, androgens and glucocorticoids as well as their receptors and steroid converting enzymes in adipose tissue has been established. Their contribution to diseases such as obesity, diabetes and hormone-dependent cancers is an active area of research. Our objective was to develop a LC-MS/MS method to quantify bioactive estrogens and glucocorticoids simultaneously in human adipose tissue. Estrogens and glucocorticoids were extracted from adipose tissue samples using solid-phase extraction. Estrogens were derivatized using 1-(2,4-dinitro-5-fluorophenyl)-4-methylpiperazine (PPZ) and methyl iodide to generate a permanently charged molecule (MPPZ). Steroids were separated and quantified by LC-MS/MS. The limit of quantitation for the steroids was between 15 and 100 pg per sample. Accuracy and precision were acceptable (<20%). Using this method, estradiol, estrone, cortisone and cortisol were quantified in adipose tissue from women with and without breast cancer. This novel assay of estrogens and glucocorticoids by LC-MS/MS coupled with derivatization allowed simultaneous quantification of a panel of steroids in human adipose tissue across the endogenous range of concentrations encountered in health and disease.


Assuntos
Tecido Adiposo/química , Estrogênios/análise , Glucocorticoides/análise , Neoplasias da Mama , Cromatografia Líquida , Cortisona/análise , Estradiol/análise , Estrona/análise , Feminino , Humanos , Hidrocortisona/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
9.
Theriogenology ; 138: 39-46, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31284220

RESUMO

Control of ovarian function in cheetahs is sub-optimal, which currently limits the integration of assisted reproductive techniques into the genetic management of that endangered species. The objective of this study was to determine the effect of preemptive progestin treatment on the quality of ovarian responses after exogenous gonadotropin stimulation in cheetahs. Adult females received either 1) 200 IU equine chorionic gonadotropin (eCG) followed with 3,000 IU porcine luteinizing hormone (pLH) (intramuscular route) (n = 5; control group) or 2) similar eCG/pLH administration preceded by a 7-day treatment with oral progestin (0.1 mg/kg altrenogest; ALT group; n = 7). At 42 h post-pLH administration, a series of metrics was assessed via laparoscopy (number of follicles ≥ 2 mm, number of corpora lutea, oviduct and uterine cornua diameter and overall vascularization). Concentrations of fecal estradiol, progesterone and glucocorticoid metabolites (FEM, FPM, and FGM, respectively) were measured by enzyme immunoassay for 3 wk before ALT treatment (Period 1), 7 d during ovarian suppression period (Period 2), throughout eCG/LH treatment and laparoscopy (Period 3), and 6 wk following laparoscopy (Period 4). Overall, nine out of 12 cheetahs (4/5 in control and 5/7 ALT group) had freshly-formed corpora lutea at the time of laparoscopy. Mean follicle and corpora lutea numbers in the control versus ALT group were not different (P > 0.05). Overall measurements and vascularization scores also did not differ (P > 0.05) among groups. FEM average concentrations increased (P ≤ 0.05) in response to eCG for the ALT-treated females between Periods 2 and 3 and were sustained during Period 4. However, FEM average concentrations did not vary (P > 0.05) for control females throughout Periods 1-4. Post-ovulatory FPM average concentrations (Period 4) did not differ (P > 0.05) between the ALT-treated females and controls. FPM average concentration from both groups increased in Period 4 compared to Periods 1-3 (P ≤ 0.05). Females receiving the ALT treatment also had lower (P ≤ 0.05) FGM metabolite average concentrations than control females during ovarian suppression (suggesting adrenal suppression). Collective results suggest that ovarian response to gonadotropin treatment in the cheetah was improved following oral progestin administration due to the normative increase in estradiol following stimulation for these females compared with control. This treatment should lead to more effective timed assisted reproduction procedures for this species.


Assuntos
Acinonyx/fisiologia , Sincronização do Estro/métodos , Gonadotropinas Equinas/farmacologia , Ovário/efeitos dos fármacos , Indução da Ovulação , Progestinas/administração & dosagem , Administração Oral , Animais , Gonadotropina Coriônica/farmacologia , Estradiol/análise , Estradiol/metabolismo , Fezes/química , Feminino , Glucocorticoides/análise , Glucocorticoides/metabolismo , Hormônio Luteinizante/farmacologia , Ovário/fisiologia , Indução da Ovulação/métodos , Indução da Ovulação/veterinária , Progesterona/análise , Progesterona/metabolismo , Progestinas/farmacologia , Resultado do Tratamento , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/análogos & derivados , Acetato de Trembolona/farmacologia
10.
Anal Chem ; 91(14): 8918-8925, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31204806

RESUMO

Visualizing tissue distribution of steroid hormones is a promising application of MALDI mass spectrometry imaging (MSI). On-tissue chemical derivatization using Girard's T reagent has enhanced the ionization efficiency of steroids. However, discriminating between structural isomers with distinct bioactivities remains a challenge. Herein, we used ion trap MS/tandem MS (MS3) to distinguish a mineralcorticoid aldosterone (Aldo) and a glucocorticoid cortisol (F), from their structural isomers. Our method is also useful to detect hybrid steroids (18-hydroxycortisol [18-OHF] and 18-oxocortisol) with sufficient signal-to-noise ratio. The clinical applicability of the tandem MS method was evaluated by analyzing F, Aldo, and 18-OHF distributions in human adrenal glands. In such clinical specimens, small Aldo-producing cell clusters (APCCs) were identified and were first found to produce a high level of Aldo and not to contain F. Moreover, a part of APCCs produced 18-OHF, presumably converted from F by APCC-specific CYP11B2 activity. Catecholamine species were also visualized with another derivatization reagent (TAHS), and those profiling successfully discriminated pheochromocytoma species. These tandem MSI-methods, coupled with on-tissue chemical derivatization has proven to be useful for detecting low-abundance steroids, including Aldo and hybrid steroids and thus identifying steroid hormone-producing lesions.


Assuntos
Glândulas Suprarrenais/química , Esteroides/análise , Aldosterona/análise , Glucocorticoides/análise , Humanos , Hidrocortisona/análogos & derivados , Hidrocortisona/análise , Isomerismo , Mineralocorticoides/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem/métodos
11.
Anal Chim Acta ; 1035: 77-86, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30224147

RESUMO

A novel fully automated liquid-phase microextraction (LPME) procedure making use of a conical polypropylene membrane bag to hold the solvent, coupled with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) with positive electrospray ionisation was developed to determine glucocorticoids (including cortisol, cortisone, dexamethasone, prednisone and prednisolone) in water. The solvent was a synergistic mixture of 10% v/v of ionic liquid, 1-butyl-3-methylimidazolium methylsulfate in n-octanol. The use of ionic liquid as an additive enhanced the extraction performance due to the favourable ionic and hydrogen bonding interactions with the analytes. Different experimental parameters such as the types of organic solvent as supported liquid membrane and ionic liquid, various composition of ionic liquid, volume of extractant phase, agitation time and speed, temperature of extraction were investigated. Under the most favourable extraction conditions, enrichment factors of 49.4-83.1 were obtained for the target compounds with relative standard deviations of <10%. The intra-day repeatability of the method ranged from 4.23 to 6.42% and the inter-day reproducibility ranged from 6.87 to 9.20%. Good linearity 0.05-50 ng mL-1 (prednisolone) and 0.1-50 ng mL-1 (all other analytes) with coefficients of determination of 0.991 or better, was obtained. The membrane bag-assisted-LPME UHPLC-MS/MS approach exhibited high sensitivity, linearity and repeatability for the extraction of the glucocorticoids and also offered an automated streamlined process, from the point where analytes were extracted, to the final analysis of the water samples. The method was employed to determine the concentration of these contaminants in the influent and effluent of a wastewater treatment plant.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Glucocorticoides/análise , Líquidos Iônicos/química , Microextração em Fase Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Oxirredutases do Álcool/química , Automação , Concentração de Íons de Hidrogênio , Microextração em Fase Líquida/instrumentação , Prednisolona/análise , Reprodutibilidade dos Testes , Singapura , Solventes/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Temperatura , Águas Residuárias/análise , Poluentes Químicos da Água/análise
12.
Sci Total Environ ; 630: 1492-1501, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29554767

RESUMO

Emission of compounds with biological activities from waste water treatment plant (WWTP) effluents into surface waters is a topic of concern for ecology and drinking water quality. We investigated the occurrence of hormone-like activities in waste water sample extracts from four Dutch WWTPs and pursued to identify compounds responsible for them. To this aim, in vitro reporter gene bioassays for androgenic, anti-androgenic, estrogenic, glucocorticoid and progestogenic activity and a UPLC-tQ-MS target analysis method for 25 steroid hormones used in high volumes in pharmacy were applied. Principal component analysis of the data was performed to further characterize the detected activities and compounds. All five types of activities tested were observed in the WWTP samples. Androgenic and estrogenic activities were almost completely removed during WW treatment, anti-androgenic activity was only found in treated WW. Glucocorticoid and progestogenic activities persisted throughout the treatment. The androgenic activity in both influent could predominantly be attributed to the presence of androstenedione and testosterone. Anti-androgenic activity was explained by the presence of cyproterone acetate. The glucocorticoid activity in influent was fully explained by prednicarbate, triamcinolone acetonide, dexamethasone and amcinonide. In effluent however, detected hormones could only explain 10-32% of the activity, indicating the presence of unknown glucocorticoids or their metabolites in effluent. Progesterone and levonorgestrel could explain the observed progestogenic activity. The principle component analysis confirmed the way in which hormones fit in the spectrum of other emerging contaminants concerning occurrence and fate in WWTPs.


Assuntos
Monitoramento Ambiental , Hormônios/análise , Poluentes Químicos da Água/análise , Androgênios/análise , Disruptores Endócrinos/análise , Estrona/análise , Glucocorticoides/análise , Progesterona/análise , Progestinas/análise , Eliminação de Resíduos Líquidos/estatística & dados numéricos , Águas Residuárias/química , Águas Residuárias/estatística & dados numéricos
13.
Talanta ; 180: 358-367, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29332823

RESUMO

In this work, computational and experimental methods were used to study the adsorption of estrogens and glucocorticoids on metal-organic frameworks (MOFs). Computer-aided molecular simulation was applied to predict the adsorption of eight analytes on four MOFs (MIL-101(Cr), MIL-100(Fe), MIL-53(Al), and UiO-66(Zr)) by examining molecular interactions and calculating free binding energies. Subsequently, the four water-stable MOFs were synthesized and evaluated as adsorbents for the target hormones in aqueous solution. As the MOF exhibiting the highest adsorption capacity in both computations and experiments, MIL-53(Al) was chosen as a sorbent to develop a dispersive micro-solid-phase extraction procedure coupled to ultra-performance liquid chromatography tandem mass spectrometry for simultaneous determination of the target analytes in water and human urine samples. Experimental parameters affecting the extraction recoveries, including pH, ionic strength, MIL-53(Al) amount, extraction time, desorption time, and desorption solvent, were optimized. The optimized method provided a linear range of 0.005025-368.6µg/L with good correlation coefficients (0.9982 ≤ r2 ≤ 0.9992), and limits of detection (S/N = 3) and quantification (S/N = 10) of 0.0015-1.0µg/L and 0.005-1.8µg/L, respectively. The analyte recoveries were in the range of 80.6-98.4% in water samples and 88.4-93.2% in urine samples. Furthermore, MIL-53(Al) showed good stability over 10 extraction cycles (RSD < 10.0%). Good agreement between experimental measurements and computational results showed the potential of this approach for elucidating adsorption mechanisms and predicating extraction efficiencies for MOFs and targets, providing new directions for the development and utilization of MOFs.


Assuntos
Estrogênios/análise , Estrogênios/urina , Glucocorticoides/análise , Glucocorticoides/urina , Estruturas Metalorgânicas/química , Microextração em Fase Sólida/métodos , Água/análise , Cromatografia Líquida de Alta Pressão/métodos , Simulação por Computador , Estrogênios/isolamento & purificação , Glucocorticoides/isolamento & purificação , Humanos , Limite de Detecção , Modelos Moleculares , Espectrometria de Massas em Tandem/métodos , Termodinâmica
14.
São Paulo; s.n; s.n; 2018. 88 p. graf, tab.
Tese em Português | LILACS | ID: biblio-980422

RESUMO

Estudos envolvendo os glicocorticoides merecem destaque devido a serem hormônios responsáveis pela transferência de informações e instruções às células, desta forma regulando o metabolismo, desenvolvimento, crescimento, função imune e também auxiliam no controle das funções tanto reprodutivas quanto tecidual. Estes também são sintetizados e amplamente utilizados com finalidade terapêutica processos alérgicos, tratamento de doenças autoimunes, em transplantes no pré-operatório e/ou pós-operatório-, devido a sua eficiente ação como imunossupressores e anti-inflamatórios. Os dois primeiros capítulos deste trabalho exibem uma revisão da literatura com foco em considerações gerais sobre os glicocorticoides, metodologias empregadas na análise destes hormônios e fundamentos da eletroforese capilar. Na sequência, o quarto capitulo, mostra a otimização da separação de 17 glicocorticoides utilizando cromatografia eletrocinética micelar devido a alto grau hidrofóbico dos analitos. Para tal, a composição do eletrólito consistiu em 20mM de tetraborato de sódio (pH=9.3) e 30 mM de dodecil sulfato de sódio (como surfactante), e a interação soluto-micela e, portanto, retenção do soluto, foi manipulada com a adição (volume/volume) de solventes orgânicos na composição de até 20% acetonitrila (ACN), 20% etanol (EtOH) e 1% tetrahidrofurano (THF), a qual se baseia num modelo de desenho de misturas (totalizando dez diferentes eletrólitos), e através desta abordagem um ótimo de separação foi obtido (13,3% EtOH, 3,3% ACN e 0,17% THF). A melhor condição de separação foi testada qualitativamente numa amostra de urina de um voluntário que faz uso contínuo de prednisona como terapia corticoidal. As misturas de solventes estudadas neste trabalho afetam a solubilidade dos hormônios na fase aquosa e a estrutura micelar também sofre grande impacto,principalmente na camada de solvatação. O quarto capítulo busca racionalizar tais efeitos através da obtenção de descritores, e as informações contidas nos descritores hidrofóbicos e hidrofílicos são sempre relevantes e contribuem nas correlações encontradas. Obteve três grupos de comportamento distinto, onde a capacidade doadora e aceptora de prótons para a realização de ligações de hidrogênios foram as interações consideradas as mais relevantes para o comportamento observado da separação. E o capítulo final, apresenta possibilidades de aproveitamento no controle de qualidade na indústria farmacêutica, métodos baseados na injeção e tensão inversas foram propostos a fim de ganho de tempo de análise (máximo de 5 minutos), estes foram validados seguindo o protocolo preconizado pela ANVISA (Agência Nacional de Vigilância Sanitária) nos parâmetros: precisão, exatidão, seletividade, linearidade, limites de detecção e quantificação e robustez; e aplicados na quantificação de quatro (diferentes formulações comerciais contendo glicocorticoides (prednisona 20 mg, betametasona 4 mg, furoato de mometasona 200 mcg e dipropionato de beclometasona 200 mcg)


Studies involving glucocorticoids deserve to be highlighted because they are hormones responsible for the transfer of information and instructions to cells, thus regulating metabolism, development, growth, immune function and also assist in the control of both reproductive and tissue functions. These are also synthesized and widely used for therapeutic purposes - allergic processes, treatment of autoimmune diseases, in preoperative and/or postoperative transplants - due to their efficient action as immunosuppressants and anti-inflammatories. The first two chapters of this paper present a review of the literature focusing on general considerations about glucocorticoids, methodologies used in the analysis of these hormones and fundamentals of capillary electrophoresis. Subsequently, the fourth chapter shows the optimization of the separation of 17 glucocorticoids using micellar electrokinetic chromatography due to the high hydrophobic degree of the analytes. To this end, the electrolyte composition consisted of 20 mM sodium tetraborate (pH = 9.3) and 30 mM sodium dodecyl sulfate (as a surfactant), and the solute-micelle interaction and therefore solute retention was manipulated with organic solvent in the composition of up to 20% acetonitrile (ACN), 20% ethanol (EtOH) and 1% tetrahydrofuran (THF), which is based on a mixture design model (totaling ten different electrolytes), and through this approach an optimal separation was obtained (13.3% EtOH, 3.3% ACN and 0.17% THF). The best separation condition was qualitatively tested in a urine sample from a volunteer who makes continuous use of prednisone as corticosteroid therapy. The solvent mixtures studied in this work affect the solubility of the hormones in the aqueous phase and the micellar structure also has a great impact, especially on the solvation layer. The fourth chapter seeks to rationalize these effects by obtainingdescriptors, and the information contained in the hydrophobic and hydrophilic descriptors is always relevant and contributes to the correlations found. It obtained three groups of distinct behavior, where the donor and acceptor capacity of protons for the realization of hydrogen bonds were the interactions considered the most relevant for the observed behavior of the separation. And the final chapter presents possibilities of use in quality control in the pharmaceutical industry, methods based on injection and reverse voltage were proposed in order to gain analysis time (maximum of 5 minutes), these were validated following the protocol recommended by ANVISA (Brazilian National Agency of Sanitary Surveillance) in the parameters: precision, accuracy, selectivity, linearity, limits of detection and quantification and robustness; and applied in the quantification of four different commercial formulations containing glucocorticoids (prednisone 20 mg, betamethasone 4 mg, mometasone furoate 200 mcg and beclomethasone dipropionate 200 mcg)


Assuntos
Eletroforese Capilar , Composição de Medicamentos , Glucocorticoides/análise , Esteroides , Cromatografia Capilar Eletrocinética Micelar/métodos
15.
Se Pu ; 35(8): 816-825, 2017 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29048815

RESUMO

A novel method was developed for the simultaneous rapid determination of 81 illegally added glucocorticoids (GCs) in cosmetics using dispersive-solid phase extraction (d-SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The analytes were extracted by acetonitrile after dispersing with water, and then purified using the C18 and primary secondary amine (PSA). The chromatographic separations were performed on a Poroshell 120 PFP column (100 mm×2.1 mm, 2.7 µ m) under multiple chromatographic retention modes. Acetonitrile and 0.2% (v/v) acetic acid aqueous solution were used as mobile phases with gradient elution, and all the 10 groups of isomers were baseline separated. The qualitative identification and quantitative analysis of the 81 GCs were operated in the electrospray ionization positive mode using dynamic multiple reaction monitoring (DMRM). The 81 GCs finally were quantified by internal standard method. The correlation coefficients of linear calibration curves were greater than 0.99 in the corresponding mass concentration ranges. The average recoveries of the 81 GCs at three spiked levels ranged from 68.8% to 105.3% with relative standard deviations (RSDs) of 2.9%-13.1% (n=6). The LODs (S/N ≥ 3) and LOQs (S/N ≥ 10) were 0.002-0.006 µ g/g and 0.005-0.020 µ g/g, respectively. A number of 137 cosmetic samples submitted by customers were screened. Sixteen positive samples were found, and the contents of GCs were from 16.9 µ g/g to 158 µ g/g. The results showed that the new method is simple, rapid, sensitive and reliable, and it is suitable for qualitative and quantitative screening analysis of the 81 GCs in cosmetics simultaneously.


Assuntos
Cromatografia Líquida , Cosméticos/química , Glucocorticoides/análise , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Extração em Fase Sólida
16.
Singapore Med J ; 58(3): 115-120, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28361161

RESUMO

Local healthcare providers often question the possible steroidal activity of traditional Chinese medicine (TCM) herbs or herbal products and implicate them as a cause for adrenal insufficiency or Cushing's syndrome in patients with a history of TCM intake. We conducted a comprehensive database search for evidence of potential glucocorticoid, mineralocorticoid, androgenic or oestrogenic activity of herbs or herbal products. Overall, there are not many herbs whose steroidal activity is well established; among these, most cases were based on preclinical studies. Liquorice root may cause pseudoaldosteronism through interference with the steroidogenesis pathway. Although ginseng and cordyceps have some in vitro glucocorticoid activities, the corroborating clinical data is lacking. Deer musk and deer antler contain androgenic steroids, while epimedium has oestrogenic activity. On the other hand, adulteration of herbal products with exogenous glucocorticoids is a recurrent problem encountered locally in illegal products masquerading as TCM. Healthcare providers should stay vigilant and report any suspicion to the relevant authorities for further investigations.


Assuntos
Medicamentos de Ervas Chinesas/análise , Medicina Tradicional Chinesa/efeitos adversos , Esteroides/análise , Androgênios/análise , Animais , Cordyceps , Bases de Dados Factuais , Cervos , Medicamentos de Ervas Chinesas/efeitos adversos , Epimedium , Estrogênios/análise , Ácidos Graxos Monoinsaturados , Glucocorticoides/análise , Glycyrrhiza uralensis , Humanos , Mineralocorticoides/análise , Panax , Preparações de Plantas/análise , Risco , Singapura , Esteroides/efeitos adversos , Extratos de Tecidos
17.
J Chromatogr A ; 1465: 9-19, 2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27562415

RESUMO

The present work describes the development of a novel fully automated online solid phase extraction (SPE) coupled with high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) using negative electrospray ionisation (ESI) for the simultaneous determination of six estrogens and six glucocorticoids in water. Filtered water samples (5mL) were preconcentrated on a HyperSep™ Retain PEP SPE cartridge, eluted in back-flush mode, and separated on an LC column before analysis by tandem mass spectrometry. The total analysis time for each sample was 17min. Different experimental parameters such as the type of online SPE cartridge, loading flow rate, and composition of methanol in the loading phase were optimised. The intra-day repeatability of method ranged from 1.48 to 9.68% for all analytes, and the inter-day reproducibility ranged from 2.03 to 8.63% for all analytes, except for dexamethasone at 11.95%. These were calculated based on the peak area responses of the targeted analytes spiked at 50ng/L in ultrapure water. The method also showed good linearity from 1 to 100ng/L, with the limits of detection (LODs) ranging from 0.16 to 2.14ng/L. The proposed method was applied to the analysis of municipal wastewater. This fully automated online SPE extraction coupled with LC-MS/MS method is effective and reliable to measure estrogens and glucocorticoids simultaneously due to its high throughput, relatively low solvent consumption, reusability of the online SPE cartridge, and reduction of manual labor.


Assuntos
Cromatografia Líquida , Monitoramento Ambiental/métodos , Estrogênios/análise , Glucocorticoides/análise , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Água/química , Automação Laboratorial , Congêneres do Estradiol , Limite de Detecção , Reprodutibilidade dos Testes , Águas Residuárias/análise , Poluentes Químicos da Água/análise
18.
Pesqui. vet. bras ; 36(7): 652-656, jul. 2016. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: lil-794775

RESUMO

The thymus is a lymphoid organ and usually evaluated for the degree of lymphocyte loss with subjective histological techniques. This study aimed to adapt and to apply of the digital analysis of the lymphoid depletion system (ADDL) in the thymus in order to obtain a more accurate analysis. Glucocorticoid was used to induce immunosuppression in 55 broilers at 21 days of age; other 15 broilers were the control group. After euthanasia of the broilers, postmortem examination was made. Both thymic chains were collected and six lobes were selected for histological examination of the degree of lymphocyte depletion (scores 1 to 5) and for submission to all stages of processing by the ADDL system. The artificial constructed neural networks (ANN) obtained 94.03% of correct classifications. In conclusion, it was possible to adopt objective criteria to evaluate thymic lymphoid depletion with the ADDL system.(AU)


O timo é um órgão linfóide, que é normalmente avaliado para o grau de perda de linfócitos a partir de técnicas histológicas subjetivas. Este trabalho teve como objetivo a adaptação e aplicação do sistema de análise digital de depleção linfóide (ADDL) para o timo, a fim de tornar sua análise mais acurada. Glicocorticóides foram utilizados a fim de induzir imunossupressão em 55 aves de 21 dias de idade. Outras 15 aves formaram o grupo controle. Posteriormente, para cada um dos aves, realizou-se a eutanásia e necropsia. Ambas as cadeias do timo foram coletadas e foram selecionadas seis lóbulos para processamento histológico, análise quanto ao grau de depleção linfocitária (escores de 1-5) e submissão a todas as fases do processamento pelo sistema ADDL. Observou-se que a rede neural artificial (RNA) construída obteve 94,03% de classificações corretas. Em conclusão, foi possível adotar critérios objetivos para avaliar a depleção linfóide tímica utilizando o sistema ADDL.(AU)


Assuntos
Animais , Galinhas/fisiologia , Imunidade Celular/fisiologia , Depleção Linfocítica/veterinária , Linfócitos/fisiologia , Rede Nervosa/fisiologia , Timo/fisiopatologia , Glucocorticoides/análise
19.
J Vis Exp ; (110)2016 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-27168477

RESUMO

Adrenal activity can be assessed in the equine species by analysis of feces for corticosterone metabolites. During a potentially aversive situation, corticotrophin releasing hormone (CRH) is released from the hypothalamus in the brain. This stimulates the release of adrenocorticotrophic hormone (ACTH) from the pituitary gland, which in turn stimulates release of glucocorticoids from the adrenal gland. In horses the glucocorticoid corticosterone is responsible for several adaptations needed to support equine flight behaviour and subsequent removal from the aversive situation. Corticosterone metabolites can be detected in the feces of horses and assessment offers a non-invasive option to evaluate long term patterns of adrenal activity. Fecal assessment offers advantages over other techniques that monitor adrenal activity including blood plasma and saliva analysis. The non-invasive nature of the method avoids sampling stress which can confound results. It also allows the opportunity for repeated sampling over time and is ideal for studies in free ranging horses. This protocol describes the enzyme linked immunoassay (EIA) used to assess feces for corticosterone, in addition to the associated biochemical validation.


Assuntos
Glucocorticoides/metabolismo , Cavalos/metabolismo , Técnicas Imunoenzimáticas/métodos , Glândulas Suprarrenais/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Animais , Corticosterona/metabolismo , Fezes/química , Feminino , Glucocorticoides/análise , Masculino , Reprodutibilidade dos Testes
20.
Artigo em Inglês | MEDLINE | ID: mdl-27055356

RESUMO

Synthetic and natural steroid hormones have attracted some attention in recent years as endocrine active substances (EAS) that interact or interfere with the endocrine system. Endogenous hormones occur naturally in food of animal origin, among which bovine milk represents an important source. This study was conducted to determine the occurrence of steroid hormones (oestrogens, androgens, progestogens and glucocorticoids) in cow's milk samples from three farms in Switzerland. An isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of 12 hormones in milk. Some hormonal levels from individual cows showed large variations. The average levels of the hormones analysed (17α-estradiol = 31 ng kg(-)(1), 17ß-estradiol = 6 ng kg(-)(1), estrone = 159 ng kg(-)(1), 4-androstenedione = 684 ng kg(-)(1), progesterone = 15486 ng kg(-)(1), 17-hydroxyprogesterone = 214 ng kg(-)(1), cortisone = 112 ng kg(-)(1), and cortisol = 235 ng kg(-)(1)) were comparable with literature data. Estriol, testosterone and androstenediols were not detected at their respective limit of quantification. No significant differences of hormonal content among milk from cows at different lactation/calving numbers were evidenced, except for progesterone and 4-androstenedione. Due to confounding parameters linked to the physiological stage of the animal, like pregnancy and gestational stage (pregnancy trimester), the causal correlation between the variation of the levels for these two hormones and the lactation/calving number could not be unambiguously demonstrated.


Assuntos
Androgênios/análise , Estrogênios/análise , Contaminação de Alimentos , Inspeção de Alimentos/métodos , Glucocorticoides/análise , Leite/química , Progestinas/análise , Animais , Animais Endogâmicos , Bovinos , Cromatografia Líquida de Alta Pressão , Indústria de Laticínios , Resíduos de Drogas/análise , Feminino , Técnicas de Diluição do Indicador , Lactação , Gravidez , Espectrometria de Massas por Ionização por Electrospray , Suíça , Espectrometria de Massas em Tandem
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