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Acid Ethyl Esters (acid + ethyl_ester)
Kinds of Acid Ethyl Esters Selected AbstractsUnexpected Isolation of 4-Isothiocyanatomethylene-4H-pyridine-1-carboxylic Acid Ethyl Ester as Potential Template in Organic Synthesis.CHEMINFORM, Issue 5 2006Aladdin E. Sarhan Abstract For Abstract see ChemInform Abstract in Full Text. [source] Fatty Acid Ethyl Esters in Meconium: Are They Biomarkers of Fetal Alcohol Exposure and Effect?ALCOHOLISM, Issue 7 2006Enrique M. Ostrea Jr. Background: Biomarkers of fetal exposure to alcohol are important to establish so that early detection and intervention can be made on these infants to prevent undesirable outcomes. The aim of this study was to analyze long-chain fatty acid ethyl esters (FAEEs) in meconium as potential biomarkers of fetal alcohol exposure and effect. Methods: Fatty acid ethyl esters were analyzed in the meconium of 124 singleton infants by positive chemical ionization gas chromatography/mass spectrometry (GC/MS) and correlated to maternal ethanol use. Results: A total of 124 mother/infant dyads were enrolled in the study: 31 were in the control group and 93 were in the alcohol-exposed group. The incidence (28% vs 9.7%, p=0.037) of ethyl linoleate detected in meconium was significantly higher in the alcohol-exposed groups than the control groups. Similarly, when the concentrations of ethyl linoleate in meconium were grouped (trichotomized), there was a significant linear by linear association between alcohol exposure and group concentrations of ethyl linoleate (p=0.013). Furthermore, only alcohol-exposed infants were found in the group with the highest ethyl linoleate concentration. The sensitivity of ethyl linoleate in detecting prenatal alcohol exposure was only 26.9%, and its specificity and positive predictive value were 96.8 and 96.2%, respectively. There was no significant correlation between the concentration of ethyl linoleate in meconium and absolute alcohol consumed (oz) per drinking day across pregnancy, although a trend toward a positive correlation is seen at lower amounts of alcohol consumed. Among the polyunsaturated, long-chain FAEEs, there was weak evidence that the incidence (21.5% vs 6.5%, p=0.057) and concentration (p=0.064) of ethyl arachidonate (AA) were significantly higher in the alcohol-exposed groups than the control groups. Ethyl linolenate and ethyl docosahexanoate (DHA) in meconium were found only in the alcohol group, although not at statistically significant levels. Highly significant correlations were found among the concentrations of ethyl linoleate, ethyl linolenate, ethyl AA, and ethyl DHA in meconium (correlations ranged between rs=0.203, p=0.024; and rs=0.594, p<0.001). Conclusion: We conclude that FAEEs in meconium, particularly ethyl linoleate and ethyl AA, are biomarkers of high specificity for prenatal exposure to alcohol in newborn infants. We also propose that ethyl AA and DHA could be potential biomarkers of fetal alcohol effects on the developing fetal brain and should be investigated further. [source] Detection of Recent Ethanol Intake With New Markers: Comparison of Fatty Acid Ethyl Esters in Serum and of Ethyl Glucuronide and the Ratio of 5-Hydroxytryptophol to 5-Hydroxyindole Acetic Acid in UrineALCOHOLISM, Issue 5 2005K Borucki Background: At present, recent ethanol consumption can be routinely detected with certainty only by direct measurement of ethanol concentration in blood or urine. Because ethanol is rapidly eliminated from the circulation, however, the time span for this detection is in the range of hours. Several new markers have been proposed to extend the detection interval, but their characteristics have not yet justified their use in routine clinical practice. We therefore investigated three new markers and compared their kinetics and sensitivities: (1) fatty acid ethyl esters (FAEEs) in serum, (2) ethyl glucuronide (EtG) in urine, and (3) the ratio of 5-hydroxytryptophol to 5-hydroxyindole acetic acid (5-HTOL/5-HIAA) in urine. Methods: Seventeen healthy men participated in a drinking experiment. Blood and urine samples were collected twice daily on three consecutive days and once daily on days 4 and 5. Ethanol concentration was determined by gas chromatography, FAEE levels, by gas chromatography with mass spectrometry, EtG concentration, by liquid chromatography-tandem mass spectrometry, and 5-HTOL/5-HIAA ratio, by high-performance liquid chromatography. Results: The peak serum ethanol concentrations of the subjects ranged from 5.4 to 44.7 mmol/liter (mean ± SD, 30.1 ± 9.1 mmol/liter). In the case of the serum ethanol determination, 100% sensitivity was reached only immediately after the end of the drinking experiment, and in the case of FAEE levels and 5-HTOL/5-HIAA ratio, it tested for 6.7 hr after the end of the ethanol intake. Thereafter, these latter parameters declined until 15.3 hr (FAEEs) and 29.4 hr (5-HTOL/5-HIAA), subsequently remaining in a stable range until 78.5 hr without further decrease. In contrast, EtG concentration showed 100% sensitivity until 39.3 hr and thereafter decreased, falling to below the limit of quantification of 0.1 mg/liter at 102.5 hr. Conclusion: After moderate drinking, EtG in the urine proved to be a superior marker of recent ethanol consumption in healthy subjects. This is because EtG is a direct ethanol metabolite, it occurs in the urine only when ethanol has been consumed, and its sensitivity remains at the level of 100% for 39.3 hr. [source] In Heavy Drinkers Fatty Acid Ethyl Esters in the Serum Are Increased for 44 hr After Ethanol ConsumptionALCOHOLISM, Issue 7 2004Katrin Borucki Background: Fatty acid ethyl esters (FAEEs) have been proposed as a marker of ethanol consumption because they can be detected for up to 24 hr after a moderate intake of ethanol, even though blood ethanol remains increased for only 8 hr. Therefore, this study investigated whether FAEEs can be found during a time period exceeding 24 hr in a group of patients who were hospitalized for ethanol detoxification. A second aim was to study the distribution of FAEEs between lipoproteins during that time. Methods: Serum samples of 12 patients with acute ethanol intoxication were assayed for FAEEs. Blood samples were drawn 8.2, 20.2, 32.2, and 44.2 hr after hospitalization. FAEEs were quantified by gas chromatography-mass spectrometry. Results: Ethanol was no longer detectable after 20.2 hr from hospitalization, whereas FAEEs were still found after 32.2 and 44.2 hr. These late FAEEs were significantly higher than the FAEEs in 15 different healthy men who had abstained from ethanol for 4.5 days (p < 0.001 and p= 0.001). FAEEs were associated mainly with lipid-free serum but tended to accumulate in very-low-density lipoprotein in patients with moderate hypertriglyceridemia. Conclusions: In heavy drinkers, the FAEEs were increased after ethanol consumption for at least 44 hr. It remains to be studied whether they originate from a single ethanol intake or, in addition, from a slow release out of body storage compartments. [source] A Linchpin Approach to Unsaturated Fatty Acids: 11,12-Epoxyeicosatrienoic Acid and 11S,12S-Dihydroxyeicosatrienoic Acid Ethyl Esters.CHEMINFORM, Issue 52 2005Douglass F. Taber No abstract is available for this article. [source] Synthesis and Antimicrobial Activity of {2-[2-(N,N-Disubstituted thiocarbamoyl-sulfanyl)acylamino]thiazol-4-yl}acetic Acid Ethyl Esters.CHEMINFORM, Issue 28 2003Oeznur Ates No abstract is available for this article. [source] ChemInform Abstract: Synthesis and Biological Data of 4-Amino-1-(2-chloro-2-phenylethyl)-1H-pyrazolo [3,4-b]pyridine-5-carboxylic Acid Ethyl Esters, a New Series of A1 -Adenosine Receptor (A1AR) Ligands.CHEMINFORM, Issue 5 2002Silvia Schenone Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Modeling of extraction behavior of docosahexaenoic acid ethyl ester by utilizing slug flow prepared by microreactorAICHE JOURNAL, Issue 8 2010Eiji Kamio Abstract The liquid,liquid extraction dynamics of an ethyl ester of docosahexaenoic acid (DHA-Et) with silver ion was investigated. The kinetic model was derived according to the following stepwise processes: Diffusion of DHA-Et across the organic film, complex-formation between DHA-Et and silver ion at the interface, and diffusion of extracted complex across the aqueous film. The kinetic parameters for the complex-formation reaction were determined from the investigation with the stirred transfer cell. With the proposed model and determined parameters, we predicted the uptakes of DHA-Et for the extraction system utilizing a slug flow prepared by a microchip. The calculated uptakes showed good correlation to the experimental data. The theoretical investigation suggested that the fast equilibration realized for the slug flow extraction system was due to the large specific interfacial area of the slug caused by the presence of wall film and the thin liquid film caused by the internal circulation. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Radiosynthesis of [11C]ximelagatran via palladium catalyzed [11C]cyanationJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 1 2008Anu J. Airaksinen Abstract N -hydroxyamidines (amidoximes) may be used in prodrug technology in improving oral bioavailability of drugs containing amidino functional groups. In the body, amidoximes are reduced quickly to amidines by enzymes that are present in several organs. Ximelagatran is a benzamidoxime and ethyl ester prodrug of melagatran, which is a thrombin inhibitor. Our aim was to develop a fast and efficient labeling route for the synthesis of [11C]ximelagatran ([11C]3) with a label in a metabolically stable position. [11C]3 was synthesized via a two-step synthesis sequence, starting from palladium catalyzed [11C]cyanation of its corresponding bromide precursor (2-[2-(4-bromo-benzylcarbamoyl)-azetidin-1-yl]-1-cyclohexyl-2-oxo-ethyl amino-acetic acid ethyl ester) (1), followed by a reaction with hydroxylamine. [11C]3 was synthesized with 27±17% total overall decay corrected yield (specific radioactivity of 2360±165,Ci/mmol at EOS), with a total synthesis time of 45,min. A fast and efficient labeling route for the synthesis of [11C]3 was developed. Copyright © 2008 John Wiley & Sons, Ltd. [source] Preparation of HPLC chiral packing materials using cellulose tris(4-methylbenzoate) for the separation of chrysanthemate isomersJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 17 2006Chiyo Yamamoto Abstract We investigated the separation of chrysanthemate isomers (1), particularly the (1R)-trans form, by high-performance liquid chromatography (HPLC) using polysaccharide derivatives, such as the phenylcarbamates and benzoates of cellulose and amylose, as the chiral stationary phases (CSPs). The chiral packing materials (CPMs) having a high chiral recognition for the chrysanthemic acid ethyl ester (1a) were prepared by coating cellulose tris(4-methylbenzoate) (2a) dissolved in solvents containing methyl benzoate or acetophenone as an additive on silica gel. The separation factor for 1a significantly depended on the preparation conditions of CPM 2a, such as the coating amount of 2a and the type and amount of additives. The chiral recognition ability created by imprinting the additives was lost when the CPM was heated at a high temperature, and was recovered by contacting it with the additive in a packed column. The structural change in 2a during these treatments was not clearly detected by spectroscopic methods. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5087,5097, 2006 [source] Nature versus nurture in two highly enantioselective esterases from Bacillus cereus and Thermoanaerobacter tengcongensisMICROBIAL BIOTECHNOLOGY, Issue 1 2010Stephan Grosse Summary There is an increasing need for the use of biocatalysis to obtain enantiopure compounds as chiral building blocks for drug synthesis such as antibiotics. The principal findings of this study are: (i) the complete sequenced genomes of Bacillus cereus ATCC 14579 and Thermoanaerobacter tengcongensis MB4 contain a hitherto undescribed enantioselective and alkaliphilic esterase (BcEST and TtEST respectively) that is specific for the production of (R)-2-benzyloxy-propionic acid ethyl ester, a key intermediate in the synthesis of levofloxacin, a potent antibiotic; and (ii) directed evolution targeted for increased thermostability of BcEST produced two improved variants, but in either case the 3,5°C increase in the apparent melting temperature (Tm) of the mutants over the native BcEST that has a Tm of 50°C was outperformed by TtEST, a naturally occurring homologue with a Tm of 65°C. Protein modelling of BcEST mapped the S148C and K272R mutations at protein surface and the I88T and Q110L mutations at more buried locations. This work expands the repertoire of characterized members of the ,/,-fold hydrolase superfamily. Further, it shows that genome mining is an economical option for new biocatalyst discovery and we provide a rare example of a naturally occurring thermostable biocatalyst that outperforms experimentally evolved homologues that carry out the same hydrolysis. [source] Estimating driver risk using alcohol biomarkers, interlock blood alcohol concentration tests and psychometric assessments: initial descriptivesADDICTION, Issue 2 2010Paul Marques ABSTRACT Aim To identify alcohol biomarker and psychometric measures that relate to drivers' blood alcohol concentration (BAC) patterns from ignition interlock devices (IIDs). Design, setting, participants, measurements In Alberta, Canada, 534 drivers, convicted of driving under the influence of alcohol (DUI), installed IIDs and agreed to participate in a research study. IID BAC tests are an established proxy for predicting future DUI convictions. Three risk groups were defined by rates of failed BAC tests. Program entry and follow-up blood samples (n = 302, 171) were used to measure phosphatidyl ethanol (PETH), carbohydrate deficient transferrin (%CDT), gamma glutamyltransferase (GGT) and other biomarkers. Program entry urine (n = 130) was analyzed for ethyl glucuronide (ETG) and ethyl sulphate (ETS). Entry hair samples were tested for fatty acid ethyl esters (FAEE) (n = 92) and ETG (n = 146). Psychometric measures included the DSM-4 Diagnostic Interview Schedule Alcohol Module, Alcohol Use Disorders Identification Test (AUDIT), the time-line follow-back (TLFB), the Drinker Inventory of Consequences (DRINC) and the Temptation and Restraint Inventory (TRI). Findings Except for FAEE, all alcohol biomarkers were related significantly to the interlock BAC test profiles; higher marker levels predicted higher rates of interlock BAC test failures. PETH, the strongest with an overall analysis of variance F ratio of 35.5, had significant correlations with all nine of the other alcohol biomarkers and with 16 of 19 psychometric variables. Urine ETG and ETS were correlated strongly with the IID BAC tests. Conclusions The findings suggest that several alcohol biomarkers and assessments could play an important role in the prediction and control of driver alcohol risk when re-licensing. [source] Improvement of enantioselectivity and stability of Klebsiella oxytoca hydrolase immobilized on Eupergit C 250LJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 11 2008Pei-Yun Wang Abstract BACKGROUND: A simple procedure was employed to covalently immobilize a Klebsiella oxytoca hydrolase (SNSM-87) onto epoxy-activated supports of Eupergit C 250L via multipoint covalent attachment. The resultant biocatalyst was explored for the hydrolytic resolution of a variety of (R,S)-2-hydroxycarboxylic acid ethyl esters. RESULTS: With the hydrolytic resolution of (R,S)-ethyl mandelate in biphasic media as the model system, optimal conditions of 55 °C, pH 6 buffer and isooctane as the organic phase were selected for improving the enzyme stability (activity retained from 10% to 50% at 96 h) and enantioselectivity (VSVR,1 value enhanced from 44 to 319) in comparison to the performance of free enzyme. Moreover, the immobilized enzyme retained its activity and enantioselectivity after eight cycles of hydrolysis at 55 °C. When applying the resolution process to other (R,S)-2-hydroxycarboxylic acid ethyl esters, 2.4- to 4.0-fold enhancements of the enantioselectivity in general were obtainable. CONCLUSIONS: The enantioselectivity enhancement, good reusability and easy recovery after reaction indicate that the immobilized SNSM-87 may have the potential as an industrial biocatalyst for the preparation of optically pure 2-hydroxycarboxylic acids. Copyright © 2008 Society of Chemical Industry [source] Integrated synthesis and extraction of short-chain fatty acid esters by supercritical carbon dioxideAICHE JOURNAL, Issue 4 2010Marta Lubary Abstract We developed an efficient, integrated reaction-extraction process for the production of short-chain fatty acid ethyl esters (FAEE) from milk fat, using carbon dioxide as the only processing solvent. FAEE were synthesized using a short-chain fatty acid selective lipase. The expansion of the liquid mixture of reactants by dense carbon dioxide enhanced the apparent lipase selectivity. In situ extraction of FAEE by a continuous flow of supercritical carbon dioxide proved to increase the lipase production rate. When the integrated process was operated with alternated periods of synthesis and product removal, the overall selectivity for short-chain FAEE increased as well, as a result of the combination of the selectivities of lipase and extraction solvent. A two-fold increase of the lipase productivity was achieved at these conditions, compared to a single batch reaction. The developed process enables the synthesis and isolation of high-value fatty acid derivatives from a natural source such as milk fat. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Theoretical study of the gas-phase decomposition of neutral ,-amino acid ethyl esters.JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 3 2003Elimination of ethyl picolinate, Part , ethyl 1-methylpipecolinate Abstract Theoretical studies of the thermolysis in the gas phase of two ,-amino acid ethyl esters, ethyl picolinate and ethyl 1-methylpipecolinate, were carried out using ab initio theoretical methods, at the MP2/6,31G(d) and MP2/6,311+G(2d,p) levels of theory. The reactions studied have two steps: the first corresponds to the formation of a neutral amino acid intermediate via a six-membered cyclic transition state, and the second is the rapid decarboxylation of this intermediate via a five-membered cyclic transition state. The progress of the first step of the reactions was followed by means of the Wiberg bond indices. The results indicate that the transition states have an intermediate character between reactants and products, and the calculated synchronicities show that the reactions are concerted and slightly asynchronous. The bond-breaking processes are more advanced than the bond-forming processes, indicating a bond deficiency in the transition states. The kinetic parameters calculated for both reactions agree very well with the available experimental results. Copyright © 2003 John Wiley & Sons, Ltd. [source] Determination of eight fatty acid ethyl esters in meconium samples by headspace solid-phase microextraction and gas chromatography,mass spectrometryJOURNAL OF SEPARATION SCIENCE, JSS, Issue 14 2010Marli Roehsig Abstract A number of fatty acid ethyl esters (FAEEs) have recently been detected in meconium samples. Several of these FAEEs have been evaluated as possible biomarkers for in utero ethanol exposure. In the present study, a method was optimized and validated for the simultaneous determination of eight FAEEs (ethyl laurate, ethyl myristate, ethyl palmitate, ethyl palmitoleate, ethyl stearate, ethyl oleate, ethyl linoleate and ethyl arachidonate) in meconium samples. FAEEs were extracted by headspace solid-phase microextraction. Analyte detection and quantification were carried out using GC-MS operated in chemical ionization mode. The corresponding D5-ethyl esters were synthesized and used as internal standards. The LOQ and LOD for each analyte were <150 and <100,ng/g, respectively. The method showed good linearity (r2>0.98) in the concentration range studied (LOQ , 2000,ng/g). The intra- and interday imprecision, given by the RSD of the method, was lower than 15% for all FAEEs studied. The validated method was applied to 63 authentic specimens. FAEEs could be detected in alcohol-exposed newborns (>600,ng/g cumulative concentration). Interestingly, FAEEs could also be detected in some non-exposed newborns, although the concentrations were much lower than those measured in exposed cases. [source] Fatty Acid Ethyl Esters in Meconium: Are They Biomarkers of Fetal Alcohol Exposure and Effect?ALCOHOLISM, Issue 7 2006Enrique M. Ostrea Jr. Background: Biomarkers of fetal exposure to alcohol are important to establish so that early detection and intervention can be made on these infants to prevent undesirable outcomes. The aim of this study was to analyze long-chain fatty acid ethyl esters (FAEEs) in meconium as potential biomarkers of fetal alcohol exposure and effect. Methods: Fatty acid ethyl esters were analyzed in the meconium of 124 singleton infants by positive chemical ionization gas chromatography/mass spectrometry (GC/MS) and correlated to maternal ethanol use. Results: A total of 124 mother/infant dyads were enrolled in the study: 31 were in the control group and 93 were in the alcohol-exposed group. The incidence (28% vs 9.7%, p=0.037) of ethyl linoleate detected in meconium was significantly higher in the alcohol-exposed groups than the control groups. Similarly, when the concentrations of ethyl linoleate in meconium were grouped (trichotomized), there was a significant linear by linear association between alcohol exposure and group concentrations of ethyl linoleate (p=0.013). Furthermore, only alcohol-exposed infants were found in the group with the highest ethyl linoleate concentration. The sensitivity of ethyl linoleate in detecting prenatal alcohol exposure was only 26.9%, and its specificity and positive predictive value were 96.8 and 96.2%, respectively. There was no significant correlation between the concentration of ethyl linoleate in meconium and absolute alcohol consumed (oz) per drinking day across pregnancy, although a trend toward a positive correlation is seen at lower amounts of alcohol consumed. Among the polyunsaturated, long-chain FAEEs, there was weak evidence that the incidence (21.5% vs 6.5%, p=0.057) and concentration (p=0.064) of ethyl arachidonate (AA) were significantly higher in the alcohol-exposed groups than the control groups. Ethyl linolenate and ethyl docosahexanoate (DHA) in meconium were found only in the alcohol group, although not at statistically significant levels. Highly significant correlations were found among the concentrations of ethyl linoleate, ethyl linolenate, ethyl AA, and ethyl DHA in meconium (correlations ranged between rs=0.203, p=0.024; and rs=0.594, p<0.001). Conclusion: We conclude that FAEEs in meconium, particularly ethyl linoleate and ethyl AA, are biomarkers of high specificity for prenatal exposure to alcohol in newborn infants. We also propose that ethyl AA and DHA could be potential biomarkers of fetal alcohol effects on the developing fetal brain and should be investigated further. [source] Detection of Recent Ethanol Intake With New Markers: Comparison of Fatty Acid Ethyl Esters in Serum and of Ethyl Glucuronide and the Ratio of 5-Hydroxytryptophol to 5-Hydroxyindole Acetic Acid in UrineALCOHOLISM, Issue 5 2005K Borucki Background: At present, recent ethanol consumption can be routinely detected with certainty only by direct measurement of ethanol concentration in blood or urine. Because ethanol is rapidly eliminated from the circulation, however, the time span for this detection is in the range of hours. Several new markers have been proposed to extend the detection interval, but their characteristics have not yet justified their use in routine clinical practice. We therefore investigated three new markers and compared their kinetics and sensitivities: (1) fatty acid ethyl esters (FAEEs) in serum, (2) ethyl glucuronide (EtG) in urine, and (3) the ratio of 5-hydroxytryptophol to 5-hydroxyindole acetic acid (5-HTOL/5-HIAA) in urine. Methods: Seventeen healthy men participated in a drinking experiment. Blood and urine samples were collected twice daily on three consecutive days and once daily on days 4 and 5. Ethanol concentration was determined by gas chromatography, FAEE levels, by gas chromatography with mass spectrometry, EtG concentration, by liquid chromatography-tandem mass spectrometry, and 5-HTOL/5-HIAA ratio, by high-performance liquid chromatography. Results: The peak serum ethanol concentrations of the subjects ranged from 5.4 to 44.7 mmol/liter (mean ± SD, 30.1 ± 9.1 mmol/liter). In the case of the serum ethanol determination, 100% sensitivity was reached only immediately after the end of the drinking experiment, and in the case of FAEE levels and 5-HTOL/5-HIAA ratio, it tested for 6.7 hr after the end of the ethanol intake. Thereafter, these latter parameters declined until 15.3 hr (FAEEs) and 29.4 hr (5-HTOL/5-HIAA), subsequently remaining in a stable range until 78.5 hr without further decrease. In contrast, EtG concentration showed 100% sensitivity until 39.3 hr and thereafter decreased, falling to below the limit of quantification of 0.1 mg/liter at 102.5 hr. Conclusion: After moderate drinking, EtG in the urine proved to be a superior marker of recent ethanol consumption in healthy subjects. This is because EtG is a direct ethanol metabolite, it occurs in the urine only when ethanol has been consumed, and its sensitivity remains at the level of 100% for 39.3 hr. [source] In Heavy Drinkers Fatty Acid Ethyl Esters in the Serum Are Increased for 44 hr After Ethanol ConsumptionALCOHOLISM, Issue 7 2004Katrin Borucki Background: Fatty acid ethyl esters (FAEEs) have been proposed as a marker of ethanol consumption because they can be detected for up to 24 hr after a moderate intake of ethanol, even though blood ethanol remains increased for only 8 hr. Therefore, this study investigated whether FAEEs can be found during a time period exceeding 24 hr in a group of patients who were hospitalized for ethanol detoxification. A second aim was to study the distribution of FAEEs between lipoproteins during that time. Methods: Serum samples of 12 patients with acute ethanol intoxication were assayed for FAEEs. Blood samples were drawn 8.2, 20.2, 32.2, and 44.2 hr after hospitalization. FAEEs were quantified by gas chromatography-mass spectrometry. Results: Ethanol was no longer detectable after 20.2 hr from hospitalization, whereas FAEEs were still found after 32.2 and 44.2 hr. These late FAEEs were significantly higher than the FAEEs in 15 different healthy men who had abstained from ethanol for 4.5 days (p < 0.001 and p= 0.001). FAEEs were associated mainly with lipid-free serum but tended to accumulate in very-low-density lipoprotein in patients with moderate hypertriglyceridemia. Conclusions: In heavy drinkers, the FAEEs were increased after ethanol consumption for at least 44 hr. It remains to be studied whether they originate from a single ethanol intake or, in addition, from a slow release out of body storage compartments. [source] Biomarkers for detection of prenatal alcohol exposure: A critical review of fatty acid ethyl esters in meconium,,BIRTH DEFECTS RESEARCH, Issue 7 2008Larry Burd Abstract BACKGROUND: The objective of this study was a review of published studies utilizing measurement of fatty acid ethyl esters (FAEE) in meconium as biomarkers for prenatal alcohol exposure. METHODS: We completed a literature search of PubMed using the terms meconium, fatty acid ethyl esters, biomarkers, and prenatal alcohol exposure. We included only peer reviewed studies utilizing analysis of meconium for the presence of FAEE in humans through the year 2007. RESULTS: We found 10 articles reporting on original research examining the relationship of FAEE from meconium and prenatal alcohol exposure (PAE). The 10 articles used six different PAE assessment strategies and four different analytical techniques for determining FAEE endpoints. The articles included 2,221 subjects (range 4 to 725) with 455 (20.5%) subjects identified as exposed using the methods stated in the articles. FAEE levels above the studies' respective cutoffs were reported for 502 (22.6%) subjects. CONCLUSIONS: The accurate identification of alcohol-exposed pregnancies represents a significant challenge in the development of FAEE detection cutoffs to maximize the sensitivity and specificity of the test. We present several options for the improvement of exposure assessment in future studies of FAEE as biomarkers for PAE. Birth Defects Research (Part A), 2008. © 2008 Wiley-Liss, Inc. [source] | ||||||||||||||||