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PubMed1994

[Evaluation of an increased blood level of GGT, CDT, methanol, acetone and isopropanol in alcohol intoxicated automobile drivers. Alcoholism indicators instead of medical-psychological examination].

Several thousand blood samples were taken from alcoholized drivers at the Blood Alcohol Examination Centre of the Institute of legal Medicine at Cologne University. These samples showed blood alcohol contents (BAC) as well as GGT, CDT, methanol, acetone and isopropanol levels which indicated alcohol addiction. The blood samples were selected by the drivers' ages and their BAC, but in some cases the GGT also played a role. In the majority of cases 1 or 2 parameters were measured. In 200 cases all four indicators were determined. The four parameters characterize a different problematic drinking behaviour. GGT characterizes chronic, long-term misuse, CDT characterizes occasional misuse, methanol characterizes current addicted drinking and acetone and isopropanol characterize metabolic disorders caused by alcohol. The importance of parameters is thoroughly discussed, also in relation to incorrectly measured positive values and the relation between alcohol consumption and -problems. Methanol values above 10 mg/kg, GGT activities above 100 U/l and CDT levels above 60 U/l provide sufficient proof of there being an alcohol problem which requires treatment. The levels of other indicators need not be above normal to determine this. The proportion of drivers under the influence of alcohol with problematic alcohol levels increases significantly when the BAC is above 2.0 per mille. However, there have been drivers with alcohol problems with lower BAC levels. DUI offenders addicted to alcohol are quite frequently over 40 years old. A correlation between the single indicators and the BAC is rarely found. If a correlation is to be found, it would be most likely with drivers whose BAC lies above 2.0 per mille. The mentioned indicators would detect an alcohol problem from the blood sample taken for the blood alcohol test. Alcohol problems may be detected and treated shortly after the DUI offence. This method is comparatively cheaper than medical-psychological-examinations as well as being based on objective and verifiable parameters.

1-Propanol↗
PubMed1993

Exogenous lipids influence permeability barrier recovery in acetone-treated murine skin.

BACKGROUND AND DESIGN: When the epidermal permeability barrier is perturbed with acetone, transcutaneous water loss returns to normal over 24 hours in parallel with the reappearance of stratum corneum lipids, derived from secreted lamellar bodies and accelerated lipid synthesis. Prior studies have demonstrated a separate requirement for cholesterol, fatty acid, and ceramide synthesis for barrier homeostasis, but the requirement for these lipids individually or together for barrier function is not known. We therefore applied these lipids alone or in various mixtures to acetone-treated hairless mouse skin and assessed barrier recovery. RESULTS: Ceramide and fatty acid alone, and their complex derivatives (cholesterol esters and cerebrosides), and two-component mixtures of fatty acid plus ceramide, cholesterol plus fatty acid, or cholesterol plus ceramide delayed barrier recovery. In contrast, complete mixtures of ceramide, fatty acid, and cholesterol allowed normal barrier recovery. Moreover, fluorescent-labeled cholesterol, fatty acid, and ceramide rapidly traversed the stratum corneum with uptake into the epidermal nucleated layers. Finally, incomplete, but not complete mixtures produce abnormal lamellar bodies, leading to abnormal stratum corneum intercellular membrane bilayers. CONCLUSIONS: (1) Topical applications of individual lipids or incomplete mixtures of lipids interfere with barrier recovery, while complete mixtures of cholesterol, fatty acid, and ceramide allow normal barrier repair; and (2) incomplete mixtures of topical lipids appear to inhibit barrier recovery at the level of the lamellar body resulting in abnormal intercellular membrane structures in the stratum corneum, abnormalities that do not occur when a complete lipid mixture is provided.

Acetone↗
PubMed1996

Selective spectrophotometric determination of glucose and fructose in the presence of aldoses using phenol-acetone reagent and cerium(III) chloride.

Aqueous mixtures of glucose and fructose produce red solutions when treated with 2% (w/v) phenol in 5% (v/v) aqueous acetone in the presence of concentrated sulfuric acid. The color is stable for days, and the red chromophore has an absorbance maximum at 568 nm. When the concentration of phenol is raised to 25%, fructose, but not glucose, produces red solutions, allowing for the selective detection of ketoses. Two complementary methods have been developed to remove the interference of ketoses in solutions containing glucose. The first one relies on the selective reduction of ketoses with sodium borohydride in the presence of cerium(III) chloride prior to the addition of the phenol-acetone reagents. The second method is based on the differential specific determination of glucose using 2% versus 25% levels of phenol. The relative sensitivities of different sugars are also presented as well as the applicability of the methods using bacterial polysaccharides for immunochemical analyses. The quantitative determination of glucose or ketoses in the polysaccharides does not require hydrolysis prior to the estimation.

Acetone↗
PubMed2003

Enantioselective direct aldol addition of acetone to aliphatic aldehydes.

The asymmetric direct aldol addition of acetone to aliphatic aldehydes catalyzed by D-proline, L-proline, and its derivatives was studied. While excellent results could be obtained in neat acetone using alpha-branched aldehydes, unbranched and beta-branched aldehydes gave moderate results. Two dipeptide derivatives, L-Pro-L-Try-CH(2)OH and L-Pro-L-Trp-OCH(3), were prepared and tested in this reaction and both were found to be able to induce enantioselectivities. The ee-values in the case of some aldehydes approached that obtained with L-proline. Immobilization of L-proline on a polystyrene resin by its carboxylic group provided a catalyst which is able to induce enantioselectivity, can be easily removed from the reaction mixture, and reused without a significant decrease in the enantioselectivity of the beta-hydroxyketones obtained in the cross-aldol additions.

Journal Article↗
PubMed2003

Locating dynamic species with X-ray crystallography and NMR spectroscopy: acetone in p-tert-Butylcalix[4]arene.

The exact location and orientation of dynamic species in structural studies continues to be a serious challenge, yet it is of paramount importance in modeling guest--host interactions so as to improve our understanding of the multiple weak interactions that govern many chemical and biological processes. The acetone guest in the tBC (p-tert-butylcalixarene) host presents such a challenge, as initial guest positions obtained from single crystal X-ray diffraction (XRD) are incompatible with the 2H NMR spectrum. A detailed consideration of the diffraction data showed that more complicated structural models could be constructed that were consistent with the NMR data and still yielded satisfactory diffraction residuals. These models agree that one acetone methyl group is inserted into the deep cavity, and that it exchanges with the second methyl group outside. The outside methyl group in turn can switch positions with the carbonyl group, but the distribution of the methyl and carbonyl groups over the two sites is not equal. One factor that poses additional difficulty in deciding between models is whether the actual space group is tetragonal (P4/n), or twinned monoclinic (P2/n). All of the structural models considered here disagree substantially with the one proposed in an earlier publication.

Journal Article↗
PubMed2001

The Effect of Solvent and Fiber Treatment on the Deposition of Organic Silane Solutions Using THF and Acetone.

To facilitate the deposition of gamma-ureidopropyltrimethoxysilane monomer onto E-glass fibers, anhydrous acetone and THF were used as carrier solvents. Untreated industrial E-glass fibers and cold water plasma treated E-glass fibers were used. Cold water plasma treatment of the fibers increased the hydrophobicity of the surface by increasing the number of hydroxyl groups at the surface; additionally, the amount of aluminium and calcium at the surface was increased. The silane was found to deposit in bilayers with an external surface due to condensed siloxane; aluminium and calcium were also condensed into the network when acetone was used as a deposition solvent. The bilayers were strongly hydrogen bonded via the ureido functional groups. When THF was used as a carrier solvent, a ureido functional surface was obtained due to the THF interfering with the condensation of the silane. The silane was deposited in conical patches of varying heights. Copyright 2001 Academic Press.

Journal Article↗
PubMed2002

Determination of acetone, 2-butanone, diethyl ketone and BTX using HSCC-UV-IMS.

A combination of a custom-designed ion mobility spectrometer (IMS) with a UV ionization source and a high speed capillary column (HSCC) has been developed as an analytical device for the sensitive detection of volatile organic compounds (VOCs), e.g. 2-propanone (acetone), 2-butanone and 3-pentanone (diethyl ketone) in the gas phase. A fast separation of the three selected substances and benzene, toluene and m-xylene (BTX) - all of which occur in human breath - has been achieved within less than four minutes at a carrier gas flow rate of 4.5 mL x min(-1). Multi-dimensional correlations presented support the interpretation of the acquired spectra of mixtures. Method detection limits were 2.7 microg x L(-1) for acetone and 2-butanone and 3.0 microg x L(-1) for diethyl ketone in nitrogen, respectively. The assay linear dynamic range is 4-320 microg x L(-1).

Journal Article↗
PubMed1983

Pyruvate decarboxylating activity in extracts from pigeon liver acetone powder.

Extracts of pigeon liver acetone powder showed, by a radiochemical method, considerable pyruvate decarboxylating activity. The 10-30% saturated ammonium sulfate fraction of these extracts required the addition of CoA, NAD+, and TPP for maximum pyruvate decarboxylating activity and presumably contained the pyruvate dehydrogenase complex (PDHC). The activity in the 40-60% saturated ammonium sulfate fraction had no requirement for CoA and/or NAD+ but had an absolute requirement for TPP. In similar preparations obtained from fresh pigeon liver, the PDHC activity was found in the 0-30% saturated ammonium sulfate fraction and only a small amount of pyruvate decarboxylating activity (independent of CoA and NAD+) was found in the 40-60% saturated ammonium sulfate fraction. The pyruvate decarboxylating activity which is found in the 40-60% saturated ammonium sulfate fraction of these extracts and has an absolute requirement for TPP, may represent pyruvate dehydrogenase (E1, EC 1.2.4.1), probably derived from PDHC by the acetone treatment at pH 7.8, or aging of the preparation.

Acetyltransferases↗
PubMed1991

Contact activation factors in plasma from women using oral contraceptives--increased levels of factor XII, kinin-free high molecular weight kininogen and acetone-activated kallikrein.

The plasma levels of FXII, prekallikrein (PK) and high- and low molecular weight kininogens (HK and LK) were measured in women on low estrogen dose (30-40 micrograms ethinylestradiol) oral contraceptives (OC) and in controls. FXIIa was assayed in acetone-treated citrated plasma (CPL) with PK and the tetrapeptide S-2222 as substrates, and in acetone-treated citrated plasma with benzamidine (BPL) with PK as substrate. The level of FXII was found to be about 20% higher in OC-plasma than in control plasma. Kallikrein was assayed in CPL with S-2222 as substrate and in BPL with the tripeptide S-2302 as substrate. No difference in PK-level was observed in the CPL-based method, whereas an increase in kallikrein activity of about 30% was registered in BPL. The levels of HK and LK were estimated both in rocket immunoassay and in bioassay of released kinin. No difference in HK-level could be registered in immunoassay, whereas the bioassay revealed a HK-level in OC-plasma of 40% of the control level. Immunoblot studies showed that a substantial part of HK in OC-plasma was present as kinin-free protein (mol. wt. 103 KD), assumed to possess a higher cofactor potency than that of native HK. Both in bioassay and immunoassay the level of LK was found to be 60% higher in OC-plasma than in control plasma. Considered together the observations on contact factors made in this study provide support for the assumption of an increased readiness for contact activation in plasma from women using OC.

Adult↗
PubMed1978

Biosynthesis of 6-keto PGF1alpha by microsomal acetone-pentane powder preparations from hog aorta, ram seminal vesicles, and bovine corpora lutea: properties of same.

Acetone-pentane powders of microsomal rich acetone precipitated fractions, have been prepared from hog aortas, ram seminal vesicles, and bovine corpora lutea. These preparations are all active in converting C14 labelled PGH2 to prostacyclin. The reaction was followed by quantitation of the spontaneous hydrolytic product, 6-keto PGF1alpha. The heat stability, pH optima, reactions with inhibitors, and other properties of these types are discussed. The comparative behavior of the respective enzyme preparations shows that while qualitatively they behave in a similar manner, quantitatively, there are significant differences between them, particularly with respect to heat treatment, and response to inhibitors.

Animals↗
PubMed1976

Exclusion of 20(22)-dehydrocholesterol as an intermediate in the biosynthesis of pregnenolone in bovine adrenocortical mitochondrial acetone-dried powder preparations.

Incubation of (22R)-(22-180)20-hydroxycholesterol with a bovine adrenocortical mitochondrial acetone-dried powder preparation in air yielded (20R, 22R)-20, (22-18O)22-dihydroxy-cholesterol. Incubation of (20S)-(20-18O)22-hydroxycholesterol yielded (20R, 22R)-(20-18O)20,22-dihydroxycholesterol. The formed glycols and the substrates reisolated at the end of the incubations had the same 18O abundance as the starting materials. No significant (20R, 22R)-20,22-dihydroxycholesterol was formed following incubation with either (E)-or (Z)-20, (22)-dehydrocholesterol. (20R,22S)-20, 22-Epoxycholesterol yielded approximately 1/5 of the amount of pregnenolone obtained in a similar incubation with cholesterol. No significant pregnenolone formation was observed with (20R, 22R)-20,22-epoxycholesterol. These results exclude a mechanism for the biosynthesis of (20R, 22R)-20,22-dihydroxycholesterol from the monohydroxylated cholesterol derivatives by way of dehydration followed by epoxidation and hydration. Similarly, the participation of an olefin and an epoxide as intermediates in the transformation of cholesterol to pregnenolone in acetone-dried powder preparations of adrenal cortex mitochondria is unlikely.

Adrenal Cortex↗
PubMed2003

Enolization of acetone in superheated water detected via radical formation.

Muoniated free radicals have been detected in muon-irradiated aqueous solutions of acetone at high temperatures and pressures. At temperatures below 250 degrees C, the radical product is consistent with muonium addition to the keto form of acetone. However, at higher temperatures, a different radical was detected, which is attributed to muonium addition to the enol form. Muon hyperfine coupling constants have been determined for both radicals over a wide range of temperatures, significantly extending the range of conditions under which these radicals and the keto-enol equilibrium have been studied.

Journal Article↗
PubMed2005

eta1:eta2-Alkynyl-bridged W-Si complexes: formation, structure, and reaction with acetone.

Reactions of (eta5-C5Me4R)(CO)2(MeCN)WMe (R = Me, Et) with HPh2SiCCtBu gave the novel alkynyl-bridged W-Si complexes, (eta5-C5Me4R)(CO)2W(mu-eta1:eta2-CCtBu)(SiPh2) (R = Me, Et), whose alkynyl ligands bridge the tungsten and silicon atoms in an eta1:eta2-coordination mode. The structures of these complexes were fully characterized, including X-ray crystallography. Treatment of (eta5-C5Me5)(CO)2W(mu-eta1:eta2-CCtBu)(SiPh2) with acetone resulted in acetone insertion into the silicon-alkynyl linkage followed by intramolecular C-H activation of the tBu group to give the chelate-type alkyl-alkene complex, (eta5-C5Me5)(CO)2W(eta1:eta2-CH2CMe2C=CHSiPh2OCMe2).

Journal Article↗
PubMed2003

Enhancing reactivity of carbonyl compounds via hydrogen-bond formation. A DFT study of the hetero-Diels-Alder reaction between butadiene derivative and acetone in chloroform.

To examine how hydrogen-bond (HB) formation involving chloroform solvent molecules influences the chemical reactivity of ketones, the hetero-Diels-Alder reaction of N,N-dimethyl-1-amino-3-methoxy-1,3-butadiene and acetone has been studied by using density functional theory (DFT) at the B3LYP/6-31G level. The effects of the chloroform on the activation energies have been modeled by means of discrete-continuum models. In the gas phase, the formation of specific HB between acetone and one and two chloroform molecules decreases the activation barriers from 19.3 to 13.6 and 8.5 kcal/mol, respectively. Inclusion of solvent effects by means of combined discrete and polarizable continuum models yields a change of molecular mechanism from a concerted to a two-step mechanism, and the first nucleophilic step is the rate-limiting step. The corresponding values of activation barriers in chloroform are 18.6 kcal/ mol (no HB), 13.5 kcal/mol (one HB), and 9.6 kcal/mol (two HBs). These theoretical results account for the experimental observation that chloroform accelerates the reaction more markedly than more polar aprotic solvent such as acetonitrile. A DFT analysis of the global electrophilicity power of the reagents provides a sound explanation about the catalytic effects of chloroform.

Journal Article↗
PubMed2005

Ultrafast photodissociation dynamics of acetone at 195 nm: II. Unraveling complex three-body dissociation dynamics by femtosecond time-resolved photofragment translational spectroscopy.

As a continuation of the preceding paper in this issue (J. Phys. Chem. A 2005, 109, 6805), we studied photodissociation dynamics of the acetone S2 (n, 3s) Rydberg state excited at 195 nm using femtosecond time-resolved photofragment translational spectroscopy. The technique, which is implemented by the combination of fs pump-probe ionization spectroscopy and kinetic energy resolved time-of-flight mass spectrometry (KETOF), measured temporal evolutions of the product kinetic energy distributions (KEDs) with a time resolution limited only by the laser pulse widths. Two methyl product KED components were resolved and assigned to the primary and secondary methyl products on the basis of their temporal behaviors. The results support the mechanism in which the primary dissociation occurs on the acetone S1 surface and provide complementary dynamical information to that discussed in the preceding paper.

Journal Article↗