Ethyl glucuronide (EtG) is a minor and direct metabolite of ethanol. EtG is incorporated into the growing hair allowing retrospective investigation of chronic alcohol abuse. In this study, we report the development and the validation of a... more
Ethyl glucuronide (EtG) is a minor and direct metabolite of ethanol. EtG is incorporated into the growing hair allowing retrospective investigation of chronic alcohol abuse. In this study, we report the development and the validation of a method using gas chromatography–negative chemical ionization tandem mass spectrometry (GC–NCI-MS/MS) for the quantification of EtG in hair. EtG was extracted from about 30mg
In this work, a solid phase spectrophotometric method in association with flow injection analysis for formaldehyde determination has been developed with direct measurement of light-absorption in C 18 material. The... more
In this work, a solid phase spectrophotometric method in association with flow injection analysis for formaldehyde determination has been developed with direct measurement of light-absorption in C 18 material. The 3,5-diacetyl-1,4-dihydrolutidine produced from the reaction between ...
Previous studies have shown that high concentrations of ethanol (≥40%) cause functional damage of the gastrointestinal epithelial barrier by direct cytotoxic effect on the epithelial cells. The effects of lower noncytotoxic doses of... more
Previous studies have shown that high concentrations of ethanol (≥40%) cause functional damage of the gastrointestinal epithelial barrier by direct cytotoxic effect on the epithelial cells. The effects of lower noncytotoxic doses of ethanol on epithelial barrier function are unknown. A major ...
Background: Folate deficiency is common in alcoholic patients, in part due to abnormal transport across membranes relevant to folate homeostasis. The reduced folate carrier (RFC) transports monoglutamyl folates across tissue membranes and... more
Background: Folate deficiency is common in alcoholic patients, in part due to abnormal transport across membranes relevant to folate homeostasis. The reduced folate carrier (RFC) transports monoglutamyl folates across tissue membranes and could be affected by chronic exposure to ethanol. The micropig model is suitable to study the effect of alcoholism on RFC and folate transport across membranes.Methods: The membrane transport of [3H]-folic acid was measured by a vacuum filtration method in jejunal brush border (JBB), liver plasma membrane (LPM), and kidney brush border (KBB) membranes vesicles from micropigs fed control or 40% ethanol diets for 12 months. RFC transcripts were analyzed by reverse transcription polymerase chain reaction in jejunal mucosa, liver, and kidney from the same animals.Results: When we compared results from three relevant membranes in control animals, the transport of [3H]-folic acid was highest in LPM, 3-fold lower in KBB (p < 0.001), and 6-fold lower in JBB (p < 0.001). The concentration of RFC transcripts per total RNA was greatest in liver, followed by kidney and jejunum. The transport of [3H]-folic acid by JBB vesicles from chronic ethanol-fed animals exhibited 2-fold lower Km and Vmax (p < 0.05), whereas there was no ethanol effect on the Vmax of [3H]-folic acid transport by LPM or KBB. RFC transcript levels were 10-fold lower in jejunal mucosa from ethanol-fed animals than in control-fed animals (p < 0.005).Conclusions: Although our findings demonstrate different RFC transcript amounts and transport efficiencies among tissues, the present studies suggest that chronic ethanol exposure decreases the intestinal absorption of folic acid by altering the expression of RFC and consequently its transport kinetics in JBB. These findings provide a mechanism for the clinical finding of reduced folic acid absorption in chronic alcoholics.
Alcohol consumption is a predominant etiological factor in the pathogenesis of chronic liver diseases, resulting in fatty liver, alcoholic hepatitis, fibrosis/cirrhosis, and hepatocellular carcinoma (HCC). Although the pathogenesis of... more
Alcohol consumption is a predominant etiological factor in the pathogenesis of chronic liver diseases, resulting in fatty liver, alcoholic hepatitis, fibrosis/cirrhosis, and hepatocellular carcinoma (HCC). Although the pathogenesis of alcoholic liver disease (ALD) involves complex and still unclear biological processes, the oxidative metabolites of ethanol such as acetaldehyde and reactive oxygen species (ROS) play a preeminent role in the clinical and pathological spectrum of ALD. Ethanol oxidative metabolism influences intracellular signaling pathways and deranges the transcriptional control of several genes, leading to fat accumulation, fibrogenesis and activation of innate and adaptive immunity. Acetaldehyde is known to be toxic to the liver and alters lipid homeostasis, decreasing peroxisome proliferator-activated receptors and increasing sterol regulatory element binding protein activity via an AMP-activated protein kinase (AMPK)-dependent mechanism. AMPK activation by ROS mod...
Three strains, RBY-1T, PHD-1, and PHD-2 were isolated from fruits in Thailand. The strains were Gram-negative, aerobic rods with polar flagella, produced acetic acid from ethanol and did not oxidize acetate and lactate. In phylogenetic... more
Three strains, RBY-1T, PHD-1, and PHD-2 were isolated from fruits in Thailand. The strains were Gram-negative, aerobic rods with polar flagella, produced acetic acid from ethanol and did not oxidize acetate and lactate. In phylogenetic trees based on 16S rRNA gene sequences and 16S-23S rRNA gene ITS sequences, the strains formed a cluster separate from the type strains of the eleven species of the genus Gluconobacter. The calculated 16S rRNA gene sequence and 16S-23S rRNA gene ITS sequence similarities were respectively 97.7-99.7% and 77.3-98.1%. DNA G+C contents were 57.2-57.6 mol%. They showed high DNA-DNA relatedness of 100% with one another but low DNA-DNA relatedness of 11-34% with the type strains of the eleven Gluconobacter species. Q-10 was a major quinone. On the basis of the genotypic and phenotypic data obtained, the three strains clearly represent a novel species, for which the name Gluconobacter nephelii sp. nov. is proposed. The type strain is strain RBY-1T (= BCC 3673...
Densities were measured for the binary mixtures of water (methanol or ethanol) and an ionic liquid (IL) 1,3diethylimidazolium diethylphosphate [EEIM][DEP] or 1-n-butyl-3-ethylimidazolium diethylphosphate [BEIM][DEP] at 1 atm and (293.15... more
Densities were measured for the binary mixtures of water (methanol or ethanol) and an ionic liquid (IL) 1,3diethylimidazolium diethylphosphate [EEIM][DEP] or 1-n-butyl-3-ethylimidazolium diethylphosphate [BEIM][DEP] at 1 atm and (293.15 to 333.15) K using a vibrating-tube densimeter. The molecular volume, standard entropy, and lattice energy of the two ILs were estimated with the Glasser theory. The excess volumes are negative for all binary mixtures studied in the whole composition range, and reach to the maximum at the mole fraction of IL being around 0.3. Besides, they decrease with increasing temperature for the aqueous solution of ILs, whilst a reverse trend is found for the IL solutions of methanol or ethanol at any concentration. The excess molar volumes were correlated successfully by a fiveparameter polynomial equation as a function of temperature and mole fraction of IL with average absolute relative deviation (ARD) of density within 0.02%.
Lignocellulosic ethanol has been considered as an alternative transportation fuel. Utilization of hemicellulosic fraction in lignocelluloses is crucial in economical production of lignocellulosic ethanol. However, this fraction has not... more
Lignocellulosic ethanol has been considered as an alternative transportation fuel. Utilization of hemicellulosic fraction in lignocelluloses is crucial in economical production of lignocellulosic ethanol. However, this fraction has not efficiently been utilized by traditional yeast Saccharomyces cerevisiae. Genetically modified S. cerevisiae, which can utilize xylose, has several limitations including low ethanol yield, redox imbalance, and undesired metabolite formation similar to native xylose utilizing yeasts. Besides, xylose uptake is a major issue, where sugar transport system plays an important role. These genetically modified and wild-type yeast strains have further been engineered for improved xylose uptake. Various techniques have been employed to facilitate the xylose transportation in these strains. The present review is focused on the sugar transport machineries, mechanisms of xylose transport, limitations and how to deal with xylose transport for xylose assimilation in ...
Aims: To examine the psychosocial correlates of substance use among adolescents in six European countries. Design: Cross-sectional school population survey (ESPAD) based on standardized methodological procedures. Setting: High schools in... more
Aims: To examine the psychosocial correlates of substance use among adolescents in six European countries. Design: Cross-sectional school population survey (ESPAD) based on standardized methodological procedures. Setting: High schools in six European countries: ...
The few controlled studies dealing with the action of alcohol on core body temperature in humans have focused on the effect of a single dose of ethanol and reported that it has a hypothermic effect. No studies report the effects of... more
The few controlled studies dealing with the action of alcohol on core body temperature in humans have focused on the effect of a single dose of ethanol and reported that it has a hypothermic effect. No studies report the effects of repeated ethanol intake over a 24-h period, a pattern of consumption much closer to the clinical condition of chronic alcoholism. We therefore designed a trial in which alcohol was repeatedly and regularly administered, with a total dose of 256 g. Nine healthy male volunteers (mean age 23.3 +/- 2.9 yr; range 21-30) each served as his own control. The circadian temperature rhythm was studied by a single-blind, randomized, crossover study that compared a 26-h alcohol session to a 26-h placebo session. The trial controlled for so-called masking effects known to affect temperature. The volunteers were in bed; the ambient temperature was maintained between 20 and 22 degrees C. Meals were standardized. And light was controlled during the night. All sessions too...
Background Disturbances in sleep patterns are a complicating factor in recovery from alcoholism. The effects of acute and chronic alcohol treatments on sleep in rats were determined.Methods Adult male Sprague-Dawley rats were acclimated... more
Background Disturbances in sleep patterns are a complicating factor in recovery from alcoholism. The effects of acute and chronic alcohol treatments on sleep in rats were determined.Methods Adult male Sprague-Dawley rats were acclimated to a temperature-controlled chamber, and electromyograms and electroencephalograms (EEGs) were obtained during 23-hr recording sessions. Time spent in rapid eye movement sleep (REMS) and non-REM sleep (NREMS), EEG slow-wave activity (SWA) during NREMS, a spectral analysis of the EEG by fast Fourier transform, and brain temperatures were determined.Results Acute exposure to alcohol (2.3 and 3.0 g/kg) by gastric intubation at the beginning of dark onset produced an increase in NREMS and a suppression of SWA. Spectral analysis revealed that during the first 4 hr there was a small increase in very-low-frequency bands (0.5–2 Hz), with a suppression of higher-frequency bands. This was followed by a suppression of low-frequency bands. A dose of 3.0 g/kg at light onset caused an increase in NREMS and a suppression of SWA. Spectral analysis revealed a suppression of low-frequency bands throughout the first 12 hr of recording but no change on high-frequency bands with light-onset alcohol. Chronic treatment with alcohol (6% alcohol in a liquid diet with pair-fed isocaloric controls) for 3 weeks produced an increase in NREMS and a decrease in EEG power density in frequency bands above 2 Hz. Chronic alcohol also reduced the circadian variation of REMS, an effect that showed a rebound 1 week after the alcohol treatment was terminated. Two weeks after the alcohol treatment was stopped, NREMS and REMS values returned to baseline.Conclusions These results demonstrate differences in the effect of acute alcohol on sleep depending on the time of administration and demonstrate that distinct alterations in sleep patterns are induced by chronic treatments in as little as 3 weeks.