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3.
Crit Rev Clin Lab Sci ; 57(8): 548-585, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32609540

RESUMO

Urine drug testing is one of the objective tools available to assess adherence. To monitor adherence, quantitative urinary results can assist in differentiating "new" drug use from "previous" (historical) drug use. "Spikes" in urinary concentration can assist in identifying patterns of drug use. Coupled chromatographic-mass spectrometric methods are capable of identifying very small amounts of analyte and can make clinical interpretation rather challenging, specifically for drugs that have a longer half-life. Polypharmacy is common in treatment and rehabilitation programs because of co-morbidities. Medications prescribed for comorbidities can cause drug-drug interaction and phenoconversion of genotypic extensive metabolizers into phenotypic poor metabolizers of the treatment drug. This can have significant impact on both pharmacokinetic (PK) and pharmacodynamic properties of the treatment drug. Therapeutic drug monitoring (TDM) coupled with PKs can assist in interpreting the effects of phenoconversion. TDM-PKs reflects the cumulative effects of pathophysiological changes in the patient as well as drug-drug interactions and should be considered for treatment medications/drugs used to manage pain and treat substance abuse. Since only a few enzyme immunoassays for TDM are available, this is a unique opportunity for clinical laboratory scientists to develop TDM-PK protocols that can have a significant impact on patient care and personalized medicine. Interpretation of drug screening results should be done with caution while considering pharmacological properties and the presence or absence of the parent drug and its metabolites. The objective of this manuscript is to review and address the variables that influence interpretation of different drugs analyzed from a rehabilitation and treatment programs perspective.


Assuntos
Monitoramento de Medicamentos/métodos , Detecção do Abuso de Substâncias/métodos , Urina/química , Líquidos Corporais/química , Interações Medicamentosas/fisiologia , Cabelo/química , Humanos , Cooperação do Paciente/estatística & dados numéricos , Medicina de Precisão/métodos , Saliva/química , Detecção do Abuso de Substâncias/tendências
4.
Sci Rep ; 9(1): 2298, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30783158

RESUMO

Our study aimed to estimate the prevalence of heavy fetal alcohol exposure through the analysis of meconium FAEEs as an objective biomarker of fetal exposure. We conducted a study on meconium samples collected nationwide through the Maternal-Infant Research on Environmental Chemicals (MIREC) Study Group. FAEE in meconium was quantified by an established headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (SPME GC-MS). Out of 1315 samples collected in 10 Canadian obstetric units coast to coast between 2008-2011, the estimated prevalence of positive meconium FAEE ranged between 1.16% and 2.40%, translating into at least 1800 new cases of FASD in Canada each year. Positive maternal self- reports of heavy alcohol use were tenfold lower (0.24%). Use of meconium FAEE revealed tenfold more cases of heavy exposure to maternal drinking than did maternal reports. The use of objective measures of maternal alcohol exposure is critical in accurately estimating risks and in monitoring effective prevention of FASD.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Ésteres/análise , Ácidos Graxos/análise , Ácidos Graxos/química , Mecônio/química , Canadá , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Microextração em Fase Sólida
5.
JAMA Pediatr ; 172(9): 851-856, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30073326

RESUMO

Importance: Polybrominated diphenyl ethers (PBDEs) are added to many consumer products as flame retardants, and their endocrine-disrupting properties are a growing health concern in pregnancy. Objective: To investigate whether in utero PBDE exposure as measured in maternal hair is associated with increased risk for hypospadias. Design, Setting, and Participants: In this case-control study, the setting was the urology clinic of a tertiary pediatric hospital between January 3, 2011, and April 1, 2013. Participants were children diagnosed as having hypospadias and their mothers and a control group of children without hypospadias and their mothers. Dates of data analysis were September 3, 2017, to December 28, 2017. Exposures: Gestational exposure to 8 PBDEs as measured in the 3-cm segment closest to the skull of maternal hair by gas chromatography-mass spectroscopy as a proxy for in utero exposure. The mothers resided in the same household for the duration of their pregnancy. Main Outcomes and Measures: Difference in total maternal hair PBDE levels between the hypospadias and control groups. Results: Total PBDE levels were significantly higher among mothers of infants with hypospadias (n = 152) (total PBDE level, 51.4 pg/mg; interquartile range, 35.8-78.5 pg/mg) than among controls (n = 64) (total PBDE level, 35.8 pg/mg; interquartile range, 18.1-69.9 pg/mg) (P = .02). Of the 152 women with sufficient hair samples for analysis in the case group, 89 completed a questionnaire and were included in a multivariable analysis, and of the 64 women with sufficient hair samples for analysis in the control group, 54 completed a questionnaire and were included in a multivariable analysis. Adjusting for potential confounders, hypospadias was associated with a relative 48.2% (95% CI, 23.2%-65.4%) higher maternal level of total PBDE levels in the multivariable analysis. Conclusions and Relevance: In this analysis, mothers of children with hypospadias were exposed during pregnancy to significantly higher levels of PBDEs. The results of this study suggest that level of exposure to PBDEs during gestation may have a role in the etiology of hypospadias.


Assuntos
Poluentes Ambientais/efeitos adversos , Retardadores de Chama/efeitos adversos , Éteres Difenil Halogenados/efeitos adversos , Hipospadia/induzido quimicamente , Exposição Materna/efeitos adversos , Adulto , Estudos de Casos e Controles , Poluentes Ambientais/análise , Feminino , Retardadores de Chama/análise , Cabelo/química , Éteres Difenil Halogenados/análise , Humanos , Lactente , Masculino , Gravidez , Proteínas Serina-Treonina Quinases
6.
Biochem Cell Biol ; 96(2): 189-197, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28793200

RESUMO

Alcohol consumption during pregnancy remains a significant cause of preventable birth defects and developmental disabilities; however, the mechanism of toxicity remains unclear. Methanol is present as a congener in many alcoholic beverages and is formed endogenously. Because ethanol is preferentially metabolized over methanol, it has been found in the sera and cerebro-spinal fluid of alcoholics. Toxicity resulting from methanol has been attributed to formic acid. Formic acid is present in significantly higher quantities in the biofluids of alcoholics. These higher levels can be cytotoxic and cause neuronal cell death. However, the adverse effects can be mitigated by adequate levels of hepatic folic acid, because formic acid elimination depends on folic acid. During pregnancy, folate concentrations are at least 2-fold higher in cord blood then in maternal blood, owing to increased folate requirements. The reverse has been demonstrated in pregnancies with alcohol abuse, suggesting downregulation of folate transporters and low fetal folate levels. Moreover, formic acid can cross the placenta and its adverse effects can be mitigated by folic acid. Thus, the combination of low fetal folate levels and presence of formic acid form a potent cytotoxic combination that may play a significant role in the etiology of fetal alcohol spectrum disorder.


Assuntos
Alcoolismo/sangue , Transtornos do Espectro Alcoólico Fetal/sangue , Transtornos do Espectro Alcoólico Fetal/prevenção & controle , Ácido Fólico , Formiatos/sangue , Alcoolismo/tratamento farmacológico , Alcoolismo/patologia , Animais , Feminino , Transtornos do Espectro Alcoólico Fetal/patologia , Ácido Fólico/farmacocinética , Ácido Fólico/uso terapêutico , Humanos , Mães
7.
Neurobiol Dis ; 91: 83-93, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26951949

RESUMO

Maternal alcohol consumption during gestation can cause serious injury to the fetus, and may result in a range of physiological and behavioral impairments, including increased seizure susceptibility, that are collectively termed fetal alcohol spectrum disorder (FASD). The cellular mechanisms underlying increased seizure susceptibility in FASD are not well understood, but could involve altered excitatory coupling of neuronal populations mediated by gap junction proteins. We utilized a mouse model of the prenatal alcohol exposure (PAE) to study the expression pattern of connexin (Cx) major components of gap junctions, and pannexin proteins, which form membrane channels, in the brain of 2-3weeks old PAE and control postnatal offspring. PAE during the first trimester-equivalent period of pregnancy in mice resulted in significant up-regulation of Cx30 mRNA and Cx30 total protein in the hippocampus of PAE animals compared to age-matched controls. Surface level expression of both dimeric and monomeric Cx30 were also found to be significantly up-regulated in both hippocampus and cerebral cortex of PAE animals compared to age-matched controls. On the membrane surface, the fast migrating form of Cx43 was found to be up-regulated in the hippocampus of PAE mice. However, we did not see any up-regulation of the phosphorylated forms of Cx43 on the membrane surface. These results indicate that the expression and processing of astrocytic connexins (Cx30, Cx43) are up-regulated in the brain of PAE offspring, and these changes could play a role in the cerebral hyperexcitability observed in these animals.


Assuntos
Álcoois/farmacologia , Astrócitos/efeitos dos fármacos , Conexina 43/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Astrócitos/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Conexina 30/genética , Conexina 30/metabolismo , Conexina 43/genética , Modelos Animais de Doenças , Feminino , Junções Comunicantes/efeitos dos fármacos , Junções Comunicantes/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Gravidez
8.
Can J Public Health ; 106(8): e509-13, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26986912

RESUMO

OBJECTIVES: To assess the percentage of women of childbearing age with suboptimal levels of folate for protecting against neural tube defects (<906 nM), and assess folate status among the elderly. METHODS: A total of 1,035 anonymous blood samples from a centralized clinical laboratory, with a catchment area across the Greater Toronto Area, were assessed for red blood cell (RBC) folate concentrations using a chemiluminescent immunoassay. Folate analysis was requested by physicians as part of clinical care. Available data included age, sex, and RBC folate concentration. Descriptive statistics were used to characterize the percent of women who had suboptimal blood folate concentrations, and a multiple regression was used to analyze determinants of folate status. RESULTS: Our data from 2013 show that 7% of women of childbearing age (15-45 years) had RBC folate concentrations below 906 nM, a substantially lower percentage than in our 2006 study (40%). Results from the multiple regression showed that age is a significant positive predictor of higher RBC folate status (p < 0.001). CONCLUSION: Compared to our earlier data, we report a significant decrease in the suboptimal folate status among women of childbearing age. We also show that age is a predictor of higher RBC folate levels. Our data are limited due to a lack of information regarding patient or physician characteristics, and to the nature of our sample, yet our results are consistent with the continued increase in folate status observed among several population-level studies in the US and Canada post-fortification. Further research is needed to determine the reasons for and future implications of this continued increase in the elderly.


Assuntos
Deficiência de Ácido Fólico/epidemiologia , Ácido Fólico/sangue , Estado Nutricional , Adolescente , Adulto , Distribuição por Idade , Idoso , Canadá/epidemiologia , Estudos de Coortes , Suplementos Nutricionais , Feminino , Alimentos Fortificados , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Defeitos do Tubo Neural/epidemiologia , Defeitos do Tubo Neural/prevenção & controle , Adulto Jovem
9.
Exp Neurol ; 280: 70-9, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26996134

RESUMO

Prenatal alcohol exposure (PAE) can lead to long-lasting neurological alterations that may predispose individuals to seizures and neurobehavioral dysfunction. To date, there exists limited information regarding the underlying pathophysiological mechanisms. The hippocampal CA3 region generates excitatory population activity, called sharp waves (SPWs), that provide an ideal model to study perturbations in neuronal excitability at the network and cellular levels. In the present study, we utilized a mouse model of PAE and used dual extracellular and whole-cell patch-clamp recordings from CA3 hippocampal pyramidal cells to evaluate the effect of 1st trimester-equivalent ethanol exposure (10% v/v) on SPW activity and excitatory/inhibitory balance. We observed that PAE significantly altered in vitro SPW waveforms, with an increased duration and amplitude, when compared to controls. In addition, PAE slices exhibited reduced pharmacological inhibition by the GABA-A receptor antagonist bicuculline (BMI) on SPW activity, and increased population spike paired-pulse ratios, all indicative of network disinhibition within the PAE hippocampus. Evaluation of PAE CA3 pyramidal cell activity associated with SPWs, revealed increased action potential cell firing, which was accompanied by an imbalance of excitatory/inhibitory synaptic drive, shifted in favor of excitation. Moreover, we observed intrinsic changes in CA3 pyramidal activity in PAE animals, including increased burst firing and instantaneous firing rate. This is the first study to provide evidence for hippocampal dysfunction in the ability to maintain network homeostasis and underlying cellular hyperexcitability in a model of PAE. These circuit and cellular level alterations may contribute to the increased propensity for seizures and neurobehavioral dysfunction observed in patients with a history of PAE.


Assuntos
Região CA3 Hipocampal/patologia , Região CA3 Hipocampal/fisiopatologia , Transtornos do Espectro Alcoólico Fetal/patologia , Células Piramidais/fisiologia , Potenciais Sinápticos/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Fármacos Atuantes sobre Aminoácidos Excitatórios/farmacologia , Feminino , GABAérgicos/farmacologia , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Patch-Clamp , Estatísticas não Paramétricas , Potenciais Sinápticos/efeitos dos fármacos
10.
J Obstet Gynaecol Can ; 37(6): 527-33, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26334605

RESUMO

OBJECTIVE: To conduct a systematic review evaluating the effectiveness of a folate-fortified oral contraceptive preparation in increasing blood folate concentrations to levels providing optimal protection against neural tube defects (> 906 nmol/L). METHODS: We searched Medline, EMBASE, Web of Science, and the Cochrane Library for human studies published from inception to June 2013 that evaluated oral contraceptive use and folate status. Case-control studies, cohort studies, and clinical trials were included. Efficacy and bioequivalence data were evaluated from included studies. RESULTS: Overall, efficacy and bioequivalence data for the folate-fortified oral contraceptive show that it is at least as effective as folic acid alone in raising blood folate concentrations, and that the concomitant administration of folate with the oral contraceptive component does not affect its absorption or kinetics. CONCLUSION: A folate-fortified oral contraceptive preparation provides an option for women to maintain blood folate levels, especially those who may be planning a family after the cessation of oral contraceptive therapy.


Objectif : Mener une analyse systématique de l'efficacité d'un contraceptif oral enrichi en folate pour ce qui est d'accroître les concentrations sanguines en folate jusqu'aux niveaux offrant une protection optimale contre les anomalies du tube neural (> 906 nmol/l). Méthodes : Nous avons mené des recherches dans Medline, EMBASE, Web of Science, et la Cochrane library en vue d'en tirer les études menées chez l'homme, publiées entre le début de nos travaux et juin 2013, qui ont évalué l'utilisation de contraceptifs oraux et les taux de folate. Les études cas-témoins, les études de cohorte et les essais cliniques ont été admis aux fins de notre analyse. Les issues ont été soumises à une méta-analyse faisant appel à un modèle à effets aléatoires. Résultats : De façon globale, les données sur l'efficacité et la bioéquivalence en ce qui concerne les contraceptifs oraux enrichis en folate indiquent que ceux-ci sont au moins aussi efficaces que l'acide folique administré seul pour ce qui est d'augmenter les concentrations sanguines en folate; elles indiquent également que l'administration concomitante de folate et d'un composé contraceptif oral n'en affecte ni l'absorption ni la cinétique. Conclusion : Les contraceptifs oraux enrichis en folate offrent une option aux femmes pour le maintien de leurs taux sanguins de folate; cette option s'avère particulièrement adaptée aux femmes qui pourraient souhaiter devenir enceintes à la suite de l'abandon de la contraception orale.


Assuntos
Androstenos , Anticoncepcionais Orais , Etinilestradiol , Ácido Fólico/administração & dosagem , Defeitos do Tubo Neural/prevenção & controle , Feminino , Humanos , Gravidez
11.
J Obstet Gynaecol Can ; 37(5): 430-438, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26168104

RESUMO

OBJECTIVE: To conduct a systematic review and meta-analysis of the effect of oral contraceptive use on plasma and red blood cell (RBC) folate concentrations. METHODS: We searched Medline, EMBASE, Web of Science, and the Cochrane library for human studies published from inception to June 2013 evaluating oral contraceptive use and folate status. Case-control studies, cohort studies, and clinical trials were included. A random-effects model of outcomes was used for the meta-analysis. RESULTS: A total of 2831 women in 17 studies were included in the analysis. In those whose plasma folate concentrations were available, there was a significant folate-lowering effect of oral contraceptives observed (mean reduction 1.27 µg/L; 95% CI 1.85 to 0.69, P < 0.001). Similarly, after analyzing data from 1389 women in 12 studies whose RBC folate concentrations were available, significantly lower folate status was observed among oral contraceptive users (mean reduction 59.32 µg/L; 95% CI 58.03 to 23.04, P < 0.001). CONCLUSION: Because of the reduction in blood folate concentrations associated with the use of oral contraceptives, it is critical for women of childbearing age to continue folate supplementation during oral contraceptive use.


Objectif : Mener une analyse systématique et une méta-analyse quant à l'effet du recours à la contraception orale sur les concentrations plasmatiques et érythrocytaires en folate. Méthodes : Nous avons mené des recherches dans Medline, EMBASE, Web of Science et la Cochrane library en vue d'en tirer les études menées chez l'homme, publiées entre le début de nos travaux et juin 2013, qui ont évalué l'utilisation de contraceptifs oraux et les taux de folate. Les études cas-témoins, les études de cohorte et les essais cliniques ont été admis aux fins de notre analyse. Un modèle à effets aléatoires quant aux issues a été utilisé dans le cadre de la méta-analyse. Résultats : Au total, 2 831 femmes issues de 17 études ont été admises à l'analyse. Chez les femmes pour lesquelles les concentrations plasmatiques en folate étaient disponibles, nous avons constaté que les contraceptifs oraux exerçaient un effet considérable d'atténuation de ces concentrations (baisse moyenne, 1,27 µg/l; IC à 95 %, 1,85 - 0,69, P < 0,001). De façon semblable, après avoir analysé les données traitant de 1 389 femmes issues de 12 études pour lesquelles les concentrations érythrocytaires en folate étaient disponibles, nous avons constaté une baisse considérable de ces concentrations chez les utilisatrices de contraceptifs oraux (baisse moyenne, 59,32 µg/l; IC à 95 %, 58,03 - 23,04, P < 0,001). Conclusion : En raison de la baisse des concentrations sanguines en folate qui sont associées à l'utilisation de contraceptifs oraux, il est crucial que les femmes en âge de procréer qui ont recours à une telle contraception continuent à prendre une supplémentation en folate.


Assuntos
Anticoncepcionais Orais/uso terapêutico , Ácido Fólico/sangue , Eritrócitos/metabolismo , Feminino , Humanos , Plasma/metabolismo , Fatores Socioeconômicos
12.
Reprod Toxicol ; 53: 127-30, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25929819

RESUMO

OBJECTIVE: To assess factors associated with low Red Blood Cell folate (RBCf) levels in an obstetric population in a tertiary centre. METHODS: Cross-sectional study. Three hundred and fifty women completed a questionnaire detailing use of folic acid supplementation, and had their RBCf levels measured. Values ≥ 906 nmol/L were considered optimal. Factors associated with optimal RBCf were assessed, individually and in a logistic regression model. RESULTS: Median RBCf was 1282 nmol/L. Thirty-five women (10%) had suboptimal levels. Predictors of suboptimal RBCf were non-Caucasian ethnicity, non-consumption of folic acid supplementations, and inadequate health care provider information regarding the benefits of folic acid consumption. CONCLUSION: Although, in our population, a high proportion of women achieved optimal levels of RBCf, some women remain at risk due to inadequate folate consumption. Patient and health care provider education regarding folate can still be improved, particularly in the groups identified to be at greater risk.


Assuntos
Ácido Fólico/sangue , Gravidez/sangue , Adulto , Cidades/epidemiologia , Estudos Transversais , Suplementos Nutricionais , Eritrócitos/metabolismo , Etnicidade , Feminino , Humanos , Quebeque/epidemiologia
13.
Ther Drug Monit ; 37(2): 270-4, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25768972

RESUMO

BACKGROUND: Human hair is a well-validated matrix for detecting a variety of xenobiotics, including drugs of abuse (cocaine, tetrahydrocannabinol, and morphine) and fatty acid ethyl ethers. Recent studies have shown that hair can also be useful in determining an individual's exposure to polybrominated diphenyl ethers (PBDEs), flame retardants that contaminate the dust in our daily environment. Hair processing before assay varies with each analyte; in particular, the wash protocol must be optimized to remove external contaminants while not affecting levels of the chemical of interest. The aim of this study was to determine whether hair needs to be washed before analysis for PBDEs, and if so, which protocol is most effective to ensure that the level of PBDEs is neither overestimated nor underestimated. METHOD: Individual hair samples from 10 adults (5 men and 5 women) were subjected to 4 different wash protocols: (1) no wash, (2) water, (3) 10% sodium dodecyl sulfate (SDS), and (4) hexane. Both the washes and hair were analyzed for 8 PBDEs by gas chromatography/mass spectrometry. RESULTS: The sum of PBDEs (ΣPBDEs) in the washes was (1) no wash: 0 pg/mg, (2) water: 0.39 ± 0.19 (mean ± SEM), (3) 10% SDS: 1.34 ± 0.68, and (4) hexane: 1.92 ± 0.87. The ΣPBDEs in the hair were: (1) no wash: 20.32 ± 3.05, (2) water: 20.30 ± 2.41, (3) 10% SDS: 19.27 ± 1.87, and (4) hexane: 16.91 ± 2.89. Washing with water, 10% SDS, and hexane decreased the PBDE levels by 1.9%, 7%, and 11.4%, respectively (P < 0.05). CONCLUSIONS: Thus, of the washes evaluated, water is the wash that had the least effect on total PBDE concentrations, providing the best evaluation of an individual's exposure to PBDEs.


Assuntos
Exposição Ambiental/análise , Retardadores de Chama/análise , Cabelo/química , Éteres Difenil Halogenados/análise , Adulto , Monitoramento Ambiental/métodos , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
J Clin Pharmacol ; 55(2): 159-67, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25167960

RESUMO

The objective of this randomized clinical trial was to compare steady-state gestational RBC and plasma folate concentrations in pregnant women supplementing daily with 1.1 mg (regular dose) vs. 5 mg (high dose) folic acid. Thirty-seven pregnant women, who were not previously taking folic acid, were enrolled in this open-label, 2-arm, randomized clinical trial after informed consent. Participants were randomly assigned either 1.1 or 5 mg of folic acid-containing prenatals until gestational age (g.a.) 30 weeks. Plasma and RBC folate concentrations were measured at baseline, g.a.6 weeks, g.a.12 weeks, and g.a.30 weeks using a chemiluminescent immunoassay. Results showed sustained significant increase in RBC folate in the 5 mg group between g.a.6 weeks and g.a.30 weeks (P < 0.001), and between g.a.12 weeks and g.a.30 weeks (P < 0.01), whereas a significant increase in RBC folate concentrations was observed in the 1.1 mg group only between g.a.12 weeks to g.a.30 weeks (P < 0.05). Plasma folate increased in both groups from baseline to g.a.6 weeks, and then decreased between g.a.6 weeks and g.a.30 weeks, but this was not statistically significant. Plasma concentrations at g.a.30 weeks in both groups were comparable to their respective baseline concentrations. Thus, physiological changes in pregnancy alter long-term folate pharmacokinetics. Despite supplementation over an extended period of time, steady-state does not seem to be achieved in either dose group within our study.


Assuntos
Suplementos Nutricionais , Ácido Fólico/farmacocinética , Gravidez/metabolismo , Adulto , Contagem de Eritrócitos , Eritrócitos/metabolismo , Feminino , Ácido Fólico/sangue , Humanos
15.
Clin Biochem ; 47(13-14): 1169-87, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24912048

RESUMO

OBJECTIVE: The experience of chronic pain is one of the commonest reasons individuals seek medical attention, making the management of chronic pain a major issue in clinical practice. Drug metabolism and responses are affected by many factors, with genetic variations offering only a partial explanation of an individual's response. There is a paucity of evidence for the benefits of pharmacogenetic testing in the context of pain management. DESIGN AND METHODS: We reviewed the literature between 2000 and 2013, and references cited therein, using various keywords related to pain management, pharmacology and pharmacogenetics. RESULTS: Opioids continue to be the mainstay of chronic pain management. Several non-opioid based therapies, such as treatment with cannabinoids, gene therapy and epigenetic-based approaches are now available for these patients. Adjuvant therapies with antidepressants, benzodiazepines or anticonvulsants can also be useful in managing pain. Currently, laboratory monitoring of pain management patients, if performed, is largely through urine drug measurements. CONCLUSIONS: Drug half-life calculations can be used as functional markers of the cumulative effect of pharmacogenetics and drug-drug interactions. Assessment of half-life and therapeutic effects may be more useful than genetic testing in preventing adverse drug reactions to pain medications, while ensuring effective analgesia. Definitive, mass spectrometry-based methods, capable of measuring parent drug and metabolite levels, are the most useful assays for this purpose. Urine drug measurements do not necessarily correlate with serum drug concentrations or therapeutic effects. Therefore, they are limited in their use in monitoring efficacy and toxicity.


Assuntos
Adjuvantes Farmacêuticos/uso terapêutico , Analgésicos Opioides/uso terapêutico , Dor Crônica/tratamento farmacológico , Dor Crônica/genética , Interações Medicamentosas/genética , Humanos , Manejo da Dor/métodos , Farmacogenética/métodos
16.
PLoS One ; 7(5): e38057, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22666445

RESUMO

BACKGROUND: During pregnancy, the demand for folic acid increases since the fetus requires this nutrient for its rapid growth and cell proliferation. The placenta concentrates folic acid into the fetal circulation; as a result the fetal levels are 2 to 4 times higher than the maternal level. Animal and in vitro studies have suggested that alcohol may impair transport of folic acid across the placenta by decreasing expression of transport proteins. We aim to determine if folate transfer to the fetus is altered in human pregnancies with chronic alcohol consumption. METHODOLOGY/PRINCIPAL FINDINGS: Serum folate was measured in maternal blood and umbilical cord blood at the time of delivery in pregnancies with chronic and heavy alcohol exposure (n = 23) and in non-drinking controls (n = 24). In the alcohol-exposed pairs, the fetal:maternal serum folate ratio was ≤ 1.0 in over half (n = 14), whereas all but one of the controls were >1.0. Mean folate in cord samples was lower in the alcohol-exposed group than in the controls (33.15 ± 19.89 vs 45.91 ± 20.73, p = 0.04). CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that chronic and heavy alcohol use in pregnancy impairs folate transport to the fetus. Altered folate concentrations within the placenta and in the fetus may in part contribute to the deficits observed in the fetal alcohol spectrum disorders.


Assuntos
Álcoois/efeitos adversos , Exposição Ambiental/efeitos adversos , Feto/metabolismo , Ácido Fólico/metabolismo , Troca Materno-Fetal/efeitos dos fármacos , Adulto , Alcoolismo/sangue , Alcoolismo/metabolismo , Feminino , Doenças Fetais/metabolismo , Ácido Fólico/sangue , Humanos , Gravidez , Fatores de Tempo
18.
J Obstet Gynaecol Can ; 34(4): 374-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22472339

RESUMO

OBJECTIVE: To determine folic acid dosage requirements for individuals across a broad range of BMI values, using dose per kilogram lean body weight (LBW) as a primary predictor of systemic exposure. Steady-state folate concentrations of ≥ 15.9 nmol/L were assumed to be sufficient for reducing the risk for neural tube defects in the general population. METHODS: Data from a recent study of single-dose folic acid pharmacokinetics among 12 obese and 12 non-obese women of childbearing age were analyzed to determine expected steady-state concentrations. The mean folic acid dose per kilogram LBW that achieved serum folate concentrations of ≥ 15.9 nmol/L was applied to a broad range of BMI values to evaluate daily dose requirements. RESULTS: Modest differences in folic acid requirements were noted for individuals among the non-obese, overweight, and obese categories. The current supplementation guidelines suggesting a daily dose of 0.4 mg appear to satisfy the needs of women at even the upper extremes of obesity. However, because even with appropriate folate supplementation obese women have an increased risk of neural tube defects, and they may benefit from higher intake and higher serum concentrations of folic acid. CONCLUSION: Current guidelines recommend an adequate folic acid dose for obese women of childbearing age. Thus, it is unlikely that folate deficiency is associated with the elevated risk for neural tube defects in this population.


Assuntos
Índice de Massa Corporal , Peso Corporal , Ácido Fólico/administração & dosagem , Cuidado Pré-Concepcional/métodos , Suplementos Nutricionais , Cálculos da Dosagem de Medicamento , Feminino , Humanos , Defeitos do Tubo Neural/epidemiologia , Defeitos do Tubo Neural/etiologia , Defeitos do Tubo Neural/prevenção & controle , Obesidade/complicações , Gravidez , Complicações na Gravidez , Fatores de Risco
19.
Alcohol Clin Exp Res ; 36(9): 1497-506, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22432438

RESUMO

BACKGROUND: Meconium analysis for fatty acid ethyl esters (FAEEs) is a validated method for identifying heavy prenatal ethanol (EtOH) exposure. This study investigated whether delayed sample collection can result in false-positive test results for FAEEs because of collection of samples potentially contaminated with postnatally produced stool. METHODS: Serial excretions were prospectively collected from neonates born to nondrinking mothers to capture the transition from meconium to postnatal stool. These were analyzed for FAEEs using headspace-solid phase microextraction and gas chromatography-mass spectrometry. Experiments involving incubation of samples with glucose or EtOH were performed to explore a potential mechanism of FAEE elevation. RESULTS: A total of 136 samples were collected from 30 neonates during their first few days of life (median of 4 samples/baby over a mean period of 68.5 hours postpartum). Although the first-collected meconium sample tested negative for FAEEs in all babies, later samples tested above the 2 nmol/g positive cutoff in 19 of 30 babies. Median time to appearance of FAEE-positive samples was 59.2 hours postpartum. In vitro experiments demonstrated that FAEE levels can be further increased in late samples (likely containing postnatal stool) after incubation with glucose, and that FAEEs are readily formed in meconium in the presence of EtOH. CONCLUSIONS: Collection of samples excreted later in the postpartum period can lead to false-positive test results for FAEEs, which could be because of contamination with dietary components of postnatally produced stool and EtOH-producing microorganisms. Clinically, it is critical to collect the earliest possible excretion for determination of FAEEs to ensure that the FAEE content is representative of in utero EtOH exposure.


Assuntos
Depressores do Sistema Nervoso Central/metabolismo , Etanol/metabolismo , Ácidos Graxos/análise , Mecônio/química , Adulto , Carboidratos/química , Ésteres/análise , Reações Falso-Positivas , Fezes/química , Fezes/microbiologia , Feminino , Transtornos do Espectro Alcoólico Fetal , Cromatografia Gasosa-Espectrometria de Massas , Glucose/química , Humanos , Recém-Nascido , Lipase/análise , Gravidez , Estudos Prospectivos , Microextração em Fase Sólida
20.
Forensic Sci Int ; 218(1-3): 31-6, 2012 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-22047752

RESUMO

INTRODUCTION: The analysis of pediatric and adult hair is a useful non-invasive biomarker to effectively detect long term exposure to various xenobiotics, specifically drugs of abuse such as cocaine, opiates and amphetamines. Very often individuals are using, or are exposed to multiple drugs simultaneously and therefore it is important to be able to detect them in the same analysis. We have developed a sensitive and specific solid phase micro extraction (SPME) coupled with gas chromatography mass spectrometry (GC/MS) to detect 17 different analytes in hair using a single extraction method. METHOD: Five milligrams of hair is extracted overnight, subjected to solid phase extraction (SPE) and then to SPME-GC/MS. The aimed analytes include amphetamine, methamphetamine, MDA, MDMA, cocaine, benzoylecognine, norcocaine, cocaethylene, methadone, codeine, morphine, 6-AM, oxycodone, oxymorphone, hydrocodone, hydromorphone and meperidone. RESULTS: The following are the LOD of the various drugs: 0.2ng/mg hair for amphetamine, methamphetamine, MDA, MDMA, morphine, codeine, 6-AM, oxycodone, oxymorphone, hydromorphone, hydrocodone, meperidine and 0.13ng/mg hair for cocaine, benzoylecognine, cocaethylene, norcocaine and methadone. CONCLUSION: This GC/MS method is sensitive and specific to detect the presence of these 17 analytes in as little as 5mg of hair and is especially useful for newborn and child hair analysis where the amount of hair is often very limited.


Assuntos
Anfetaminas/análise , Cocaína/análise , Cromatografia Gasosa-Espectrometria de Massas , Cabelo/química , Entorpecentes/análise , Microextração em Fase Sólida , Toxicologia Forense/métodos , Humanos , Limite de Detecção , Detecção do Abuso de Substâncias/métodos
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