Search results for "Acetone"
showing 10 items of 350 documents
Distribution and differential induction of CYP2E1 by ethanol and acetone in the mesocorticolimbic system of rat
2008
Aims: The expression of cytochrome P4502E1 (CYP2E1) in the brain has been demonstrated in several regions, nevertheless there is a lack of specific studies on the constitutive expression and induction at the mesocorticolimbic system, the most relevant brain pathway in the context of drug addiction and alcoholism. Hence, we have performed a detailed study of the CYP2E1 expression and induction in three key areas of the mesocorticolimbic system of the rat brain: prefrontal cortex (PFC), nucleus accumbens (NAc), and ventral tegmental area (VTA). Methods: Expression levels of CYP2E1 were analyzed by Western blot. The induction of the enzyme in the selected brain areas by chronic acetone (1% v/v…
Biological activation of 1,3-butadiene to vinyl oxirane by rat liver microsomes and expiration of the reactive metabolite by exposed rats.
1983
When 1,3-butadiene is incubated with rat liver microsomes and NADPH both enantiomers of vinyl oxirane are formed, the amount of epoxide being dependent on incubation time, microsomal protein, and substrate concentration. Inhibition by SKF 525 A or dithiocarb as well as induction by pretreatment with phenobarbital or 20-methylcholanthrene suggest participation of cytochrome P-450 in this reaction. The amount of epoxide is enhanced by addition of 1,1,1-trichloropropene oxide and reduced by glutathione, especially in the presence of hepatic cytosol. When rats are exposed to 1,3-butadiene in a closed chamber (conditions of maximal metabolism) vinyl oxirane is exhaled and can be quantitatively d…
Increased acetone exhalation induced by metabolites of halogenated C1 and C2 compounds.
1982
Rats were exposed, in a closed desiccator jar chamber, to concentrations of various halogenated C1 and C2 compounds at which the metabolizing capacities were saturated (Vmax conditions). Within the exposure period of 50 h concentrations of the xenobiotic and of exhaled acetone were monitored in the gas phase of the system. The quantitative extent of acetone exhalation was dependent on the individual compound examined. Acetone exhalation was stimulated in presence of vinyl chloride, vinyl bromide, vinyl fluoride, vinylidene fluoride, cis- and trans-1,2-dichloroethylene, trichloroethylene, perchloroethylene, methylene chloride, chloroform, carbon tetrachloride and 1,1,2-trichloroethane. No st…
Inhalation pharmacokinetics based on gas uptake studies. IV. The endogenous production of volatile compounds.
1983
A pharmacokinetic description of production, distribution and metabolism of endogenous volatile compounds is presented. This description uses the "gas uptake model" of a closed recirculated atmosphere in which experimental animals are exposed. As an example, the production rates of acetone, under different conditions of stimulation by xenobiotics, are calculated from published experimental data. The theoretical descriptions may serve as a basis for treating the problem of hydrocarbon exhalation in toxicological experiments with compounds eliciting lipid peroxidation.
Determination of benzophenone-3 and its main metabolites in human serum by dispersive liquid–liquid microextraction followed by liquid chromatography…
2013
A new analytical method for the determination of benzophenone-3 (2-hydroxy-4-methoxybenzophenone), and its main metabolites (2,4-dihydroxybenzophenone and 2,2'-dihydroxy-4-methoxybenzophenone) in human serum is presented. The method is based on dispersive liquid-liquid microextraction (DLLME) as preconcentration and clean-up technique, followed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Acidic hydrolysis and protein precipitation with HCl 6 M (1:1) (100 °C, 1 h) were carried out before extraction. The variables involved in the DLLME process were studied. Under the optimized conditions, 70 µL of acetone (disperser solvent) and 30 µL of chloroform (extraction solvent) were …
Copurification of dihydroxyacetone-phosphate acyl-transferase and other peroxisomal proteins from liver of fenofibrate-treated rats.
1997
Dihydroxyacetone-phosphate acyl-transferase (DHAP-AT), a peroxisomal membrane-bound enzyme that catalyzes the first step of ether-glycerolipid synthesis, was purified from liver of rats treated with fenofibrate, a peroxisome proliferator. The protocol first included isolation of peroxisomes, their purification through a discontinuous gradient and solubilization of membranes in CHAPS. DHAP-AT was further purified by four chromatographic steps, namely low-pressure size-exclusion, cation-exchange, hydroxylapatite and chromatofocusing. The chromatofocusing step led to a 4000-fold increase in the specific activity of DHAP-AT with respect to the liver homogenate with a yield of about 0.2%. Trypsi…
In situ hybridization of dihydroxyacetone phosphate acyltransferase, the regulating enzyme involved in plasmalogen biosynthesis
2005
International audience; In situ hybridization can be carried out using different methods. The experimenter has to choose various parameters: the type of tissue fixation, the time of incubation, and the duration of the exposure time. All these parameters are determinant for the sensitivity and the resolution of this technique. This publication of technical aspects described different experiments performed for in situ hybridization on liver tissue. We may conclude on the parameters to optimize each step of the hybridization procedure. Moreover, this technique could be transposed to the brain and applied to little structures with a light expression of DHAP-AT.
Female-released sex pheromones mediating courtship behavior in Lysiphlebus testaceipes males.
2013
Ethological aspects and chemical communication at close-range between the sexes of Lysiphlebus testaceipes Cresson (Hymenoptera: Braconidae) have been investigated through behavioral bioassays and chemical analysis. The attractiveness toward males of whole-body extracts of females and males in hexane and acetone was evaluated, adopting male fanning behavior as a key behavioral component. Also, the activity of polar and nonpolar fraction of female-body extract in hexane obtained using solid-phase extraction technique was investigated. In order to identify cuticular compounds, male and female whole-body extracts with hexane and acetone were analyzed by gas chromatography-mass spectrometry. Th…
Influence of therapeutic and toxic doses of neuroleptics and antidepressants on energy metabolism of the isolated perfused rat brain.
1973
The isolated perfused rat brain was used for a comparative study of the effects of promazine, imipramine, monodesmethyl promazine and desipramine on cerebral energy metabolism. After perfusion for 30 min or 1 h the brain levels of the following substrates and metabolites were estimated: P-creatine, creatine, ATP, ADP, AMP, glycogen, glucose, glucose-6-P, fructose diphosphate, dihydroxyacetone-P, pyruvate, lactate, α-ketoglutarate, and ammonia. Drug concentrations of 5·10−6 M and 10−5 M in the perfusion medium caused a significant decrease of glucose-6-P alone. When the drug concentration was raised to a toxic range (10−4 M), reflected in the EEG by the pattern of secondary discharges, an ac…
Photocatalytic printing of inorganic nanopatterns via poly(styrene-block-carbosilane) copolymer thin films on titania substrates.
2009
Well-defined, ordered arrays of nanoscale depressions were obtained in linear-brush-type polystyrene-block-polycarbosilane (PS-b-PCS) diblock copolymer thin films by acetone vapor annealing and silica nanodot arrays were directly obtained from such thin films deposited on a titania substrate by one-step exposure to UV light as a result of transformation of the PCS units to silica, driven by the photocatalytic activity of titania concurrent with removal of the organic matrix.