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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Examining Different Levels of Prevention of Birth Defects and Fetal Alcohol Spectrum Disorder

Goh, Y. Ingrid 16 July 2009 (has links)
While all women hope to deliver a healthy baby, approximately 3-5% babies are affected by birth defects. Birth defects can occur naturally or be induced by teratogens. Alcohol is a known teratogen that causes fetal alcohol spectrum disorder (FASD), the most commonly known cause of neurobehavioural and neurodevelopmental deficits. Individuals affected with FASD are likely to be involved with or require additional assistance from healthcare, education, social services, and justice sectors. Due to this immense burden, effective prevention of FASD can have a major public impact. Prevention of FASD can occur at different levels: primary prevention (preventing alcohol-induced birth defects from occurring in the first place); secondary prevention (preventing alcohol-induced birth defects from developing or progressing); tertiary prevention (improving the outcome of individuals affected with FASD); and quaternary prevention (preventing another child from being affected with FASD). The objective of this thesis was to explore a multilevel birth defect and FASD prevention strategy. Primary prevention by was investigated by maternal multivitamin supplementation to optimize fetal growing conditions, as alcoholics are commonly deficient in nutrients. A meta-analysis of maternal multivitamin supplementation demonstrated a decreased risk for certain congenital anomalies and pediatric cancers. Secondary prevention was investigated by a randomized double-blinded placebo-controlled evaluating the ability of high doses of antioxidants (vitamin C and vitamin E) to mitigate the effects of prenatal alcohol exposure. The study was ceased due to safety concerns regarding high doses of vitamin C and vitamin E in preeclamptic studies. Tertiary prevention was investigated by anonymous meconium screening of babies of Grey-Bruce, Ontario residents delivering at or transferred to St. Joseph’s Health Care in London, Ontario. A 30% prevalence of fatty acid ethyl esters (FAEE) positive meconium was observed at this high-risk unit. Meconium screening is also a means of quaternary prevention since positive screens also identify mothers who were unable to stop consuming alcohol after 13 weeks of pregnancy, and therefore are at risk of delivering another child who is prenatally exposed to alcohol. The identification and engagement of these mothers into treatment programs constitutes primary prevention of FASD in subsequent pregnancies.
2

Examining Different Levels of Prevention of Birth Defects and Fetal Alcohol Spectrum Disorder

Goh, Y. Ingrid 16 July 2009 (has links)
While all women hope to deliver a healthy baby, approximately 3-5% babies are affected by birth defects. Birth defects can occur naturally or be induced by teratogens. Alcohol is a known teratogen that causes fetal alcohol spectrum disorder (FASD), the most commonly known cause of neurobehavioural and neurodevelopmental deficits. Individuals affected with FASD are likely to be involved with or require additional assistance from healthcare, education, social services, and justice sectors. Due to this immense burden, effective prevention of FASD can have a major public impact. Prevention of FASD can occur at different levels: primary prevention (preventing alcohol-induced birth defects from occurring in the first place); secondary prevention (preventing alcohol-induced birth defects from developing or progressing); tertiary prevention (improving the outcome of individuals affected with FASD); and quaternary prevention (preventing another child from being affected with FASD). The objective of this thesis was to explore a multilevel birth defect and FASD prevention strategy. Primary prevention by was investigated by maternal multivitamin supplementation to optimize fetal growing conditions, as alcoholics are commonly deficient in nutrients. A meta-analysis of maternal multivitamin supplementation demonstrated a decreased risk for certain congenital anomalies and pediatric cancers. Secondary prevention was investigated by a randomized double-blinded placebo-controlled evaluating the ability of high doses of antioxidants (vitamin C and vitamin E) to mitigate the effects of prenatal alcohol exposure. The study was ceased due to safety concerns regarding high doses of vitamin C and vitamin E in preeclamptic studies. Tertiary prevention was investigated by anonymous meconium screening of babies of Grey-Bruce, Ontario residents delivering at or transferred to St. Joseph’s Health Care in London, Ontario. A 30% prevalence of fatty acid ethyl esters (FAEE) positive meconium was observed at this high-risk unit. Meconium screening is also a means of quaternary prevention since positive screens also identify mothers who were unable to stop consuming alcohol after 13 weeks of pregnancy, and therefore are at risk of delivering another child who is prenatally exposed to alcohol. The identification and engagement of these mothers into treatment programs constitutes primary prevention of FASD in subsequent pregnancies.
3

Cocaethylene as a Biomarker in Human Hair of Concomitant Alcohol and Cocaine Use in a High-risk Population

Natekar, Aniket 26 November 2012 (has links)
Cocaethylene (CE) is a cocaine metabolite formed during alcohol and cocaine co-consumption. To our knowledge, no previous studies were conducted assessing CE as a biomarker indicating chronic excessive alcohol consumption in a suspected high-risk population. In this study, we hypothesized that hair CE can be an effective marker for alcohol consumption in a high-risk population. We recorded cocaine, benzoylecgonine, and CE levels in hair samples from individuals, establishing the predictive value of CE by comparing it to hair levels of the widely used hair fatty acid ethyl esters (FAEE), direct markers of chronic excessive alcohol consumption. CE had 14.04% sensitivity and 95.18% specificity in samples separating FAEE positive/negative results. The positive predictive value was 0.66, showing that the results for individuals with CE positive results were more than likely to be FAEE positive, but not conclusively. Thus, CE cannot be used as a definitive marker, indicating chronic excessive alcohol consumption.
4

Screening for Prenatal Alcohol Exposure using Fatty Acid Ethyl Esters as Biomarkers

Zelner, Irene 14 January 2014 (has links)
Diagnosis of fetal alcohol spectrum disorders (FASD) is challenging and typically requires confirmation of in utero alcohol exposure. Due to the poor reliability of maternal self-reports, biomarkers have emerged to address the problem of obtaining exposure history. A relatively novel method for detecting prenatal alcohol exposure is analysis of meconium for fatty acid ethyl esters (FAEEs), which are non-oxidative ethanol metabolites. Screening newborns using meconium FAEEs may facilitate early diagnosis and intervention in alcohol-affected individuals. The overall objective of this thesis is to further investigate, validate, and assess the clinical utility of meconium FAEE analysis as a screening tool for the identification of neonates at-risk for FASD. This objective was addressed in four separate studies. The first study assessed whether meconium FAEE concentrations can be predictive of ethanol-induced organ injury in fetal sheep, and determined that the levels of these esters could be used to identify fetuses at-risk for organ dysfunction that do not display overt physical signs of ethanol teratogenicity. The second study investigated the effect of delayed meconium collection and contamination with postnatal stool on FAEE analysis, and determined it to be a risk factor for false positive test results. In the third study, maternal willingness to partake in an open meconium screening program was assessed and found to be low enough to diminish the utility of meconium FAEE testing for population-based open screening. Lastly, a systematic review examining the capacity for FAEE synthesis and the enzymology of this non-oxidative metabolic pathway in mammalian organs and tissues revealed that FAEE synthesis is mediated by numerous enzymes and isoenzymes, many of which have other primary physiological functions, and that their contribution to overall FAEE-synthesis may be tissue-specific. Overall, the results of this research provide new information on the benefits, limitations, and utility of meconium FAEE testing as a screening tool for identifying prenatal alcohol exposure − a test that may be of great clinical value in the diagnosis and management of FASD.
5

Screening for Prenatal Alcohol Exposure using Fatty Acid Ethyl Esters as Biomarkers

Zelner, Irene 14 January 2014 (has links)
Diagnosis of fetal alcohol spectrum disorders (FASD) is challenging and typically requires confirmation of in utero alcohol exposure. Due to the poor reliability of maternal self-reports, biomarkers have emerged to address the problem of obtaining exposure history. A relatively novel method for detecting prenatal alcohol exposure is analysis of meconium for fatty acid ethyl esters (FAEEs), which are non-oxidative ethanol metabolites. Screening newborns using meconium FAEEs may facilitate early diagnosis and intervention in alcohol-affected individuals. The overall objective of this thesis is to further investigate, validate, and assess the clinical utility of meconium FAEE analysis as a screening tool for the identification of neonates at-risk for FASD. This objective was addressed in four separate studies. The first study assessed whether meconium FAEE concentrations can be predictive of ethanol-induced organ injury in fetal sheep, and determined that the levels of these esters could be used to identify fetuses at-risk for organ dysfunction that do not display overt physical signs of ethanol teratogenicity. The second study investigated the effect of delayed meconium collection and contamination with postnatal stool on FAEE analysis, and determined it to be a risk factor for false positive test results. In the third study, maternal willingness to partake in an open meconium screening program was assessed and found to be low enough to diminish the utility of meconium FAEE testing for population-based open screening. Lastly, a systematic review examining the capacity for FAEE synthesis and the enzymology of this non-oxidative metabolic pathway in mammalian organs and tissues revealed that FAEE synthesis is mediated by numerous enzymes and isoenzymes, many of which have other primary physiological functions, and that their contribution to overall FAEE-synthesis may be tissue-specific. Overall, the results of this research provide new information on the benefits, limitations, and utility of meconium FAEE testing as a screening tool for identifying prenatal alcohol exposure − a test that may be of great clinical value in the diagnosis and management of FASD.
6

Cocaethylene as a Biomarker in Human Hair of Concomitant Alcohol and Cocaine Use in a High-risk Population

Natekar, Aniket 26 November 2012 (has links)
Cocaethylene (CE) is a cocaine metabolite formed during alcohol and cocaine co-consumption. To our knowledge, no previous studies were conducted assessing CE as a biomarker indicating chronic excessive alcohol consumption in a suspected high-risk population. In this study, we hypothesized that hair CE can be an effective marker for alcohol consumption in a high-risk population. We recorded cocaine, benzoylecgonine, and CE levels in hair samples from individuals, establishing the predictive value of CE by comparing it to hair levels of the widely used hair fatty acid ethyl esters (FAEE), direct markers of chronic excessive alcohol consumption. CE had 14.04% sensitivity and 95.18% specificity in samples separating FAEE positive/negative results. The positive predictive value was 0.66, showing that the results for individuals with CE positive results were more than likely to be FAEE positive, but not conclusively. Thus, CE cannot be used as a definitive marker, indicating chronic excessive alcohol consumption.
7

Síntese de ésteres etílicos de ácido graxos por transesterificação direta de biomassa de microalga marinha Chlorella minutissima / Synthesis of fatty acid ethyl esters by direct transesterification of marine microalgae biomass Chlorella minutissima

Pedro, Guilherme Arantes 31 July 2017 (has links)
Atualmente, as microalgas têm se mostrado uma matéria prima de interesse para a produção de biocombustíveis, por ser uma fonte renovável, não poluente e por não competir em áreas de cultivos de alimentos. No entanto, há a necessidade de se explorar fatores e metodologias na produção de biodiesel de microalgas para que o processo seja viabilizado. Este estudo buscou potencializar o processo de transesterificação direta (extração e reação simultaneamente) da biomassa da microalga Chlorella minutíssima para a produção de ésteres etílicos brutos tendo em vista a produção de biodiesel. O processamento direto (in situ) investigou separadamente o uso da biomassa seca e úmida, sob os efeitos dos fatores etanol, clorofórmio e ácido como catalisador. A metodologia de Taguchi foi utilizada como planejamento de experimentos para potencializar a conversão e rendimento mássico em ésteres etílicos. A partir da biomassa seca, analisadas as razões de etanol/biomassa de 100, 50, 25 e 10 mL/g teve a maximização dos resultados utilizando 25 mL de etanol (86,16% em massa com 96% de conversão) e 50 mL de etanol (104% em massa com 88% de conversão), ambas, com 5 mL de clorofórmio e 1mL de ácido sulfúrico por grama de biomassa. Posteriormente, com a inclusão dos catalisadores ácidos HCl e H2SO4 como variável, investigou-se o a reação de transesterificação in situ a partir da biomassa úmida (84% em base seca). Ambos ácidos demonstraram não ter efeito sobre as repostas. A maximização tanto do rendimento mássico quanto da conversão (131,5% em massa com 84% de conversão), bem como produzir a maior quantidade de ésteres com a menor uso de reagentes, utiliza a concentração do ácido a 0,6 mol/L, 25 mL de etanol e proporção de 1:10 de clorofórmio. Tanto a partir da biomassa seca quanto a partir da biomassa úmida, a metodologia de Taguchi foi capaz de determinar os melhores ajustes das condições reacionais para a síntese de ésteres etílicos brutos sem a necessidade de aplicar condições reacionais limitadas pela construção ou segurança do projeto como irradiação de micro-ondas ou condições supercríticas. / Currently, microalgae are considered an interest feedstock for the biofuel production, since they correspond to a renewable and non-polluting source, not competing with food crops areas. However, there is a need to explore factors and methodologies in the production of microalgae biodiesel to enable the process. This study aimed to enhance the direct transesterification process (simultaneous extraction and reaction) of the Chlorella minutíssima microalgae for the crude ethyl esters production in order to produce biodiesel. The direct processing (in situ) was investigated separately dry and wet biomass use under the effects of ethanol, chloroform and acid as a catalyst. The Taguchi methodology (design of experiments) was used to increase conversion and ethyl esters mass yields. The ethanol ratios 100, 50, 25 and 10 mL/g were analyzed from dry biomass. The results were maximized using 25 mL of ethanol (86.16% by mass with 96% conversion) and 50 mL (104% by mass with 88% conversion) with 5 mL of chloroform and 1 mL of sulfuric acid per gram of biomass. Subsequently, with the inclusion of acid catalysts HCl and H2SO4 as a variable, the in situ transesterification reaction of wet biomass (84% on dry basis) was investigated. In both cases, the acids showed no effect on the responses. Mass yield and conversion were maximized (131.5% by mass with 84% conversion), as the highest number of esters with the lowest use of reagents, take 0.6 mol/L acid concentration, 25 mL ethanol and 1:10 chloroform ratio. Taguchi methodology was able to determine the best reaction conditions adjustments for crude ethyl esters synthesis from dry biomass and wet biomass were met without the need to apply reaction conditions limited by the construction or project safety, as microwave irradiation or supercritical conditions.
8

Síntese de ésteres etílicos de ácido graxos por transesterificação direta de biomassa de microalga marinha Chlorella minutissima / Synthesis of fatty acid ethyl esters by direct transesterification of marine microalgae biomass Chlorella minutissima

Guilherme Arantes Pedro 31 July 2017 (has links)
Atualmente, as microalgas têm se mostrado uma matéria prima de interesse para a produção de biocombustíveis, por ser uma fonte renovável, não poluente e por não competir em áreas de cultivos de alimentos. No entanto, há a necessidade de se explorar fatores e metodologias na produção de biodiesel de microalgas para que o processo seja viabilizado. Este estudo buscou potencializar o processo de transesterificação direta (extração e reação simultaneamente) da biomassa da microalga Chlorella minutíssima para a produção de ésteres etílicos brutos tendo em vista a produção de biodiesel. O processamento direto (in situ) investigou separadamente o uso da biomassa seca e úmida, sob os efeitos dos fatores etanol, clorofórmio e ácido como catalisador. A metodologia de Taguchi foi utilizada como planejamento de experimentos para potencializar a conversão e rendimento mássico em ésteres etílicos. A partir da biomassa seca, analisadas as razões de etanol/biomassa de 100, 50, 25 e 10 mL/g teve a maximização dos resultados utilizando 25 mL de etanol (86,16% em massa com 96% de conversão) e 50 mL de etanol (104% em massa com 88% de conversão), ambas, com 5 mL de clorofórmio e 1mL de ácido sulfúrico por grama de biomassa. Posteriormente, com a inclusão dos catalisadores ácidos HCl e H2SO4 como variável, investigou-se o a reação de transesterificação in situ a partir da biomassa úmida (84% em base seca). Ambos ácidos demonstraram não ter efeito sobre as repostas. A maximização tanto do rendimento mássico quanto da conversão (131,5% em massa com 84% de conversão), bem como produzir a maior quantidade de ésteres com a menor uso de reagentes, utiliza a concentração do ácido a 0,6 mol/L, 25 mL de etanol e proporção de 1:10 de clorofórmio. Tanto a partir da biomassa seca quanto a partir da biomassa úmida, a metodologia de Taguchi foi capaz de determinar os melhores ajustes das condições reacionais para a síntese de ésteres etílicos brutos sem a necessidade de aplicar condições reacionais limitadas pela construção ou segurança do projeto como irradiação de micro-ondas ou condições supercríticas. / Currently, microalgae are considered an interest feedstock for the biofuel production, since they correspond to a renewable and non-polluting source, not competing with food crops areas. However, there is a need to explore factors and methodologies in the production of microalgae biodiesel to enable the process. This study aimed to enhance the direct transesterification process (simultaneous extraction and reaction) of the Chlorella minutíssima microalgae for the crude ethyl esters production in order to produce biodiesel. The direct processing (in situ) was investigated separately dry and wet biomass use under the effects of ethanol, chloroform and acid as a catalyst. The Taguchi methodology (design of experiments) was used to increase conversion and ethyl esters mass yields. The ethanol ratios 100, 50, 25 and 10 mL/g were analyzed from dry biomass. The results were maximized using 25 mL of ethanol (86.16% by mass with 96% conversion) and 50 mL (104% by mass with 88% conversion) with 5 mL of chloroform and 1 mL of sulfuric acid per gram of biomass. Subsequently, with the inclusion of acid catalysts HCl and H2SO4 as a variable, the in situ transesterification reaction of wet biomass (84% on dry basis) was investigated. In both cases, the acids showed no effect on the responses. Mass yield and conversion were maximized (131.5% by mass with 84% conversion), as the highest number of esters with the lowest use of reagents, take 0.6 mol/L acid concentration, 25 mL ethanol and 1:10 chloroform ratio. Taguchi methodology was able to determine the best reaction conditions adjustments for crude ethyl esters synthesis from dry biomass and wet biomass were met without the need to apply reaction conditions limited by the construction or project safety, as microwave irradiation or supercritical conditions.
9

Diagnóstico da exposição fetal ao álcool através de biomarcadores em mecônio / Diagnosis of fetal alcohol exposure through biomarkers in meconium

Santos, Fabiana Spineti dos 24 March 2016 (has links)
A grande prevalência do consumo de álcool por mulheres em idade reprodutiva aliada à gravidez não planejada expõe a gestante a um elevado risco de se alcoolizar em algum momento da gestação, principalmente no início do período gestacional em que a maioria delas ainda não tomou ciência do fato. Assim, torna-se extremamente relevante o desenvolvimento de métodos de detecção precoce de recém-nascidos em risco de desenvolvimento de problemas do espectro dos transtornos relacionados à exposição fetal ao álcool. O objetivo desse estudo foi desenvolver, validar e avaliar a eficácia de um método de quantificação de ésteres etílicos de ácidos graxos (FAEEs) no mecônio de recém-nascidos para avaliação da exposição fetal ao álcool. Os FAEEs avaliados foram: palmitato de etila, estearato de etila, oleato de etila e linoleato de etila.O método consistiu no preparo das amostras pela extração líquido-líquido utilizando água, acetona e hexano, seguida de extração em fase sólida empregando cartuchos de aminopropilsilica. A separação e quantificação dos analitos foi realizada por cromatografia em fase gasosa acoplada à espectrometria de massas. Os limites de quantificação (LQ) variaram entre 50-100ng/g. A curva de calibração foi linear de LQ até 2000ng/g para todos os analitos. A recuperação variou de 69,79% a 106,57%. Os analitos demonstraram estabilidade no ensaio de pós-processamento e em solução. O método foi aplicado em amostras de mecônio de 160 recém-nascidos recrutados em uma maternidade pública de Ribeirão Preto-SP. O consumo de álcool materno foi reportado utilizando questionários de rastreamento validados T-ACE e AUDIT e relatos retrospectivos da quantidade e frequência de álcool consumida ao longo da gestação. A eficácia do método analítico em identificar os casos positivos foi determinada pela curva Receiver Operating Characteristic (ROC). O consumo alcoólico de risco foi identificado pelo T-ACE em 31,3% das participantes e 50% reportaram o uso de álcool durante a gestação. 51,3% dos recém-nascidos apresentaram FAEEs em seu mecônio, sendo que 33,1% apresentaram altas concentrações para a somatória dos FAEEs (maior que 500ng/g), compatível com um consumo abusivo de álcool. O oleato de etila foi o biomarcador mais prevalente e o linoleato de etila foi o biomarcador que apresentou as maiores concentrações. Houve uma variabilidade no perfil de distribuição dos FAEEs entre os indivíduos, e discordâncias entre a presença de FAEEs e o consumo reportado pela mãe. A concentração total dos FAEEs nos mecônio mostrou-se como melhor indicador da exposição fetal ao álcool quando comparado com o uso de um único biomarcador. O ponto de corte para esta população foi de aproximadamente 600ng/g para uso tipo binge (três ou mais doses por ocasião) com sensibilidade de 71,43% e especificidade de 84,37%. Este estudo reforça a importância da utilização de métodos laboratoriais na identificação da exposição fetal ao álcool. / The high prevalence of alcohol consumption by women of reproductive age combined with unplanned pregnancy exposes the mother to a high risk to intoxicate at some time during pregnancy, especially in the early gestational period in which most of them have not yet became aware of the fact. Therefore, the development of methods for early detection it is extremely relevant for the prevention of fetal alcohol exposure as well for the early assessment of neonates at risk for development of problems of the fetal alcohol spectrum. The aim of this study was to develop, validate and evaluate the effectiveness of a method for quantifying fatty acid ethyl esters (FAEEs) in meconium from newborns for evaluation of fetal alcohol exposure. The evaluated FAEEs were: ethyl palmitate, ethyl stearate, ethyl oleate and linoleate etila. The method consists in preparing the samples by liquid-liquid extraction using water, acetone and hexane, followed by solid phase extraction employing aminopropyl silica cartridges. The separation and quantitation of analytes was performed by gas chromatography coupled with mass spectrometer. Limits of quantification (LOQ) ranged between 50 and 100 ng/g. The curves calibration were linear from LQ- 2000ng / g for all analytes. The recovery ranged from 69.79% to 106.57%. The analytes demonstrated stability in post-processing assay and in stability assay for standard solutions. The method was applied in meconium samples from 160 newborns recruited in a public maternity hospital of Ribeirão Preto. The maternal alcohol consumption was assessed by validated screening questionnaires (T-ACE and AUDIT) and by retrospective self-reports about the amount and frequency of alcohol consumption during pregnancy. The effectiveness of the analytical method in identifying positive cases was determined by receiver operating characteristic curve (ROC). The risk drinking was identified by the T-ACE in 31.3% of participants and 50% of them reported alcohol use during pregnancy. 51.3% of newborns tested positive for FAEEs, and 33.1% had high concentrations for sum of FAEEs (greater than 500 ng/g), compatible with alcohol abuse. The ethyl oleate was the most prevalent biomarker and ethyl linoleate was the biomarker that showed the highest concentrations. There was a variability in the distribution profile of FAEEs between individuals, and there were disagreements between the results of FAEEs and consumption reported by the mother. The cumulative sum of FAEEs was better than individual FAEEs for interpretation of positive cases. A positive cutoff of cumulative FAEE at 600 ng/g for binge drinking was stablished with 71,43% sensitivity and 84,37% specificity. This study reinforces the importance of using laboratory methods for identifying fetal alcohol exposure.
10

Diagnóstico da exposição fetal ao álcool através de biomarcadores em mecônio / Diagnosis of fetal alcohol exposure through biomarkers in meconium

Fabiana Spineti dos Santos 24 March 2016 (has links)
A grande prevalência do consumo de álcool por mulheres em idade reprodutiva aliada à gravidez não planejada expõe a gestante a um elevado risco de se alcoolizar em algum momento da gestação, principalmente no início do período gestacional em que a maioria delas ainda não tomou ciência do fato. Assim, torna-se extremamente relevante o desenvolvimento de métodos de detecção precoce de recém-nascidos em risco de desenvolvimento de problemas do espectro dos transtornos relacionados à exposição fetal ao álcool. O objetivo desse estudo foi desenvolver, validar e avaliar a eficácia de um método de quantificação de ésteres etílicos de ácidos graxos (FAEEs) no mecônio de recém-nascidos para avaliação da exposição fetal ao álcool. Os FAEEs avaliados foram: palmitato de etila, estearato de etila, oleato de etila e linoleato de etila.O método consistiu no preparo das amostras pela extração líquido-líquido utilizando água, acetona e hexano, seguida de extração em fase sólida empregando cartuchos de aminopropilsilica. A separação e quantificação dos analitos foi realizada por cromatografia em fase gasosa acoplada à espectrometria de massas. Os limites de quantificação (LQ) variaram entre 50-100ng/g. A curva de calibração foi linear de LQ até 2000ng/g para todos os analitos. A recuperação variou de 69,79% a 106,57%. Os analitos demonstraram estabilidade no ensaio de pós-processamento e em solução. O método foi aplicado em amostras de mecônio de 160 recém-nascidos recrutados em uma maternidade pública de Ribeirão Preto-SP. O consumo de álcool materno foi reportado utilizando questionários de rastreamento validados T-ACE e AUDIT e relatos retrospectivos da quantidade e frequência de álcool consumida ao longo da gestação. A eficácia do método analítico em identificar os casos positivos foi determinada pela curva Receiver Operating Characteristic (ROC). O consumo alcoólico de risco foi identificado pelo T-ACE em 31,3% das participantes e 50% reportaram o uso de álcool durante a gestação. 51,3% dos recém-nascidos apresentaram FAEEs em seu mecônio, sendo que 33,1% apresentaram altas concentrações para a somatória dos FAEEs (maior que 500ng/g), compatível com um consumo abusivo de álcool. O oleato de etila foi o biomarcador mais prevalente e o linoleato de etila foi o biomarcador que apresentou as maiores concentrações. Houve uma variabilidade no perfil de distribuição dos FAEEs entre os indivíduos, e discordâncias entre a presença de FAEEs e o consumo reportado pela mãe. A concentração total dos FAEEs nos mecônio mostrou-se como melhor indicador da exposição fetal ao álcool quando comparado com o uso de um único biomarcador. O ponto de corte para esta população foi de aproximadamente 600ng/g para uso tipo binge (três ou mais doses por ocasião) com sensibilidade de 71,43% e especificidade de 84,37%. Este estudo reforça a importância da utilização de métodos laboratoriais na identificação da exposição fetal ao álcool. / The high prevalence of alcohol consumption by women of reproductive age combined with unplanned pregnancy exposes the mother to a high risk to intoxicate at some time during pregnancy, especially in the early gestational period in which most of them have not yet became aware of the fact. Therefore, the development of methods for early detection it is extremely relevant for the prevention of fetal alcohol exposure as well for the early assessment of neonates at risk for development of problems of the fetal alcohol spectrum. The aim of this study was to develop, validate and evaluate the effectiveness of a method for quantifying fatty acid ethyl esters (FAEEs) in meconium from newborns for evaluation of fetal alcohol exposure. The evaluated FAEEs were: ethyl palmitate, ethyl stearate, ethyl oleate and linoleate etila. The method consists in preparing the samples by liquid-liquid extraction using water, acetone and hexane, followed by solid phase extraction employing aminopropyl silica cartridges. The separation and quantitation of analytes was performed by gas chromatography coupled with mass spectrometer. Limits of quantification (LOQ) ranged between 50 and 100 ng/g. The curves calibration were linear from LQ- 2000ng / g for all analytes. The recovery ranged from 69.79% to 106.57%. The analytes demonstrated stability in post-processing assay and in stability assay for standard solutions. The method was applied in meconium samples from 160 newborns recruited in a public maternity hospital of Ribeirão Preto. The maternal alcohol consumption was assessed by validated screening questionnaires (T-ACE and AUDIT) and by retrospective self-reports about the amount and frequency of alcohol consumption during pregnancy. The effectiveness of the analytical method in identifying positive cases was determined by receiver operating characteristic curve (ROC). The risk drinking was identified by the T-ACE in 31.3% of participants and 50% of them reported alcohol use during pregnancy. 51.3% of newborns tested positive for FAEEs, and 33.1% had high concentrations for sum of FAEEs (greater than 500 ng/g), compatible with alcohol abuse. The ethyl oleate was the most prevalent biomarker and ethyl linoleate was the biomarker that showed the highest concentrations. There was a variability in the distribution profile of FAEEs between individuals, and there were disagreements between the results of FAEEs and consumption reported by the mother. The cumulative sum of FAEEs was better than individual FAEEs for interpretation of positive cases. A positive cutoff of cumulative FAEE at 600 ng/g for binge drinking was stablished with 71,43% sensitivity and 84,37% specificity. This study reinforces the importance of using laboratory methods for identifying fetal alcohol exposure.

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