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PubMed1974

Studies on antiplague haemagglutinating antibodies. Treatment of test sera with acetone and 2-mercaptoethanol.

The indirect haemagglutination (IHA) test has been widely applied in the detection of antiplague antibodies in rodent sera. In the present study, acetone treatment of the test serum was tried in order to improve the specificity of the reaction. It was shown that the IHA titres of acetone-treated sera correlated well with those of untreated sera measured by the standard method recommended by WHO. Essentially the same results were obtained with sera from experimentally immunized rodents and from captured wild rats. In addition to acetone treatment, the sera were treated with 2-mercaptoethanol (ME). The results obtained indicated that the antiplague IHA antibodies produced early after the inoculation of plague bacilli were ME-sensitive, whereas those detected in the later stages or after a second inoculation were ME-resistant. The data suggest that acetone treatment of sera could be useful for the screening of antiplague antibodies, and that treatment with ME is helpful in assessing the time of past plague infections. The present survey has also shown that the positive rates of antiplague antibodies in wild rats trapped in Kobe, one of the largest sea ports in Japan, have so far been very low.

Acetone↗
PubMed1995

Neutrotropic effects and blood levels of solvents at combined exposures: binary mixtures of toluene, o-xylene and acetone in rats and mice.

Male rats and female mice were exposed to vapours of toluene, o-xylene and acetone in basic or double concentrations or to binary combinations of basic concentrations, for 4 and 2 hours, respectively. Basic air concentrations were for rats and mice (in ppm): toluene 270 and 380, o-xylene 230 and 320, acetone 1700 and 1530, respectively. The CNS effect-inhibition of electrically evoked seizure discharge-was measured immediately after exposure and blood levels of solvents were monitored during the desaturation phase. The effect of all binary mixtures was lower than that of double concentrations of each single component, the difference being significant only in mice, and lower than the additive effects predicted on the basis of regressions of the effect on air or on blood concentrations of individual components. On the target site in the neuronal membrane, the effects of mixtures were substantially less than additive. Blood concentrations of solvents immediately after the exposure to a mixture were generally higher in aromatics and lower in acetone than after exposure to individual solvents. The decline of blood toluene and even more so that of xylene after exposure was slowed down by acetone. Presumption of additivity seems to protect safely from acute neurotropic effects of solvents at realistic exposure levels. On the other hand, substantially protracted late phases of desaturation of aromatic solvents in the presence of slowly eliminated polar solvent points to a possible underestimation of exposure by biological exposure tests.

Acetone↗
PubMedDate not supplied

[Gas chromatographic analysis of ethanol and acetone in the air exhaled by patients].

A new method for analysis of volatile endogenous compounds in exhaled air using portable gas chromatographer with photoionization detector has been developed. Detection threshold for ethanol and acetone is 0.1 mg/ml, this permitting one to omit the step of concentrating the exhaled air samples. The accuracy of detection is 5.9 to 7.7%. The concentration of endogenous ethanol in health was 0.12 to 0.3 mg/m3, that of acetone 0.6 to 2.8 mg/m3, that in cardiopulmonary patients 0.8 to 6.4 mg/m3 for ethanol and 2.9 to 47.2 mg/m3 for acetone. Fasting for 24 h led to 15-fold increase of acetone concentration in exhaled air.

Acetone↗
PubMed1993

Cyclic fluctuations in acetone concentrations in the blood and milk of clinically healthy dairy cows.

Milk samples were taken daily or twice weekly, and blood samples twice weekly, from six clinically healthy dairy cows. Acetone concentration was determined by a new headspace gas-chromatographic method that proved to be suitable in terms of practically, sensitivity and precision. The concentration of acetone in milk was closely correlated with that in blood (r2 = 0.967). There was no relationship between lacteal acetone concentration and either somatic cell count or bacterial infection. In both blood and milk there were fluctuations in acetone concentration that were synchronous between the six cows. The fluctuations were apparently cyclic, with a period of approximately 10 d. Such fluctuations have not previously been reported.

Acetone↗
PubMed1993

[Analysis of environmental and genetic influences on the urea and acetone content in milk from the breeds German spotted cattle and German brown cattle].

In total, records of 915 cows of the breed German Simmental and German Brown were available to investigate the influences of herd, month, lactation number, stage of lactation, milk production, diseases at calving, breed-Brown-Swiss blood proportion and additive-genetic effect of the cow on milk urea and acetone content. Significant differences between herds, months and lactation numbers could be shown for milk urea and acetone content. Acetone content decreased significantly in the first 100 days post partum by 0.06 mmol/l. Milk fat content was significantly correlated with milk urea and acetone. The heritabilities for milk urea were estimated in German Simmental cows as h2 = 0.06 +/- 0.04 and in German Brown cows as h2 = 0.25 +/- 0.11. Using milk samples up to 50 days post partum, heritability estimates were between h2 = 0.10 +/- 0.09 and h2 = 0.17 +/- 0.12 in German Simmental cows.

Acetone↗
PubMedDate not supplied

Effect of prostaglandin F2 alpha on free radical generation, glutathione content and microsomal oxidase activities in rat liver microsomes induced either by ethanol or acetone.

We studied the effect of prostaglandin F2 alpha on parameters related to microsomal metabolism (free radical production and lipid peroxidation, glutathione content and activity of microsomal oxidases) after an induction by ethanol or acetone combined with starvation. Long-term ethanol administration led to a significant increase in lipid peroxide formation and NADPH-dependent chemiluminescence amplified by luminol and lucigenin. At the same time hydrogen peroxide production and NADPH-stimulated lipid peroxidation were enhanced although the effect did not reach the level of statistical significance. The concentration of reduced glutathione (GSH) in the liver was decreased 2-fold, whereas oxidized glutathione (GSSG) content remained unaltered. Ethanol intoxication resulted in an increase in 7-ethoxycoumarin-O-deethylase (ECOD), 7-benzyloxycoumarin-O-deethylase (BCOD) and 7-ethoxy-resorufin-O-deethylase (EROD) activities, whereas 7-pentoxyresorufin-O-deethylase (PROD) and ethylmorphin-N-demethylase (EMND) activities were unaltered. The combination of acetone treatment with starvation resulted in a significant increase in lipid and hydrogen peroxide formation, NADPH-dependent lipid peroxidation and chemiluminescence. GSH and GSSG concentration in the liver dramatically decreased 5- and 3-fold, respectively. The acetone treatment led to significant increase in EROD, ECOD, BCOD, PROD and EMND activities. The treatment of ethanol-intoxicated rats with prostaglandin F2 alpha (PGF2 alpha) exerted more pronounced prooxidant effect on liver than action of alcohol itself. At the same time, PGF2 alpha improved most of parameters changed by acetone treatment combined with starvation, decreasing lipid peroxide and radical formation and enhancing GSH and GSSG contents.

Acetone↗
PubMed2002

Isolation and identification of surface-bound acetone enolate on Ni(111).

A surface-bound acetone enolate species has been synthesized on Ni(111) between 260 and 340 K by two different routes catalyzed by surface Ni and O atoms: deprotonation of acetone and deacetylation of acetylacetone. The reaction pathways and surface species have been identified using reflection absorption infrared spectroscopy (RAIRS) in combination with isotopic substitution and density functional theory (DFT) calculations. Acetone enolate exhibits characteristic vibrational absorption bands at 1260, 1353, and 1545 cm-1 arising from mixed modes that involve CC stretching, CH3 bending, and CO stretching. This work conclusively proves the existence of stable acetone enolate species on a metal single-crystal surface and provides its first detailed characterization.

Journal Article↗
PubMed2003

Catalytic reduction of acetone by [(bpy)Rh]+: a theoretical mechanistic investigation and insight into cooperativity effects in this system.

Lahav, Milstein, and co-workers reported that the complex [(bpy)Rh(hd)](+)PF(6)(-) (bpy = substituted bipyridine ligand, hd = 1,5-hexadiene) shows catalytic activity in the hydrogenation of acetone (Töllner, K. et al. Science 1997, 278, 2100). The activity in an ordered monolayer was found to be dramatically greater than in solution. We used the DFT functional mPW1K (Lynch, B. J. et al. J. Phys. Chem. A 2000, 104, 4811) to investigate the mechanism of the homogenous reaction. The suitability of the mPW1K functional was verified by coupled cluster calculations on a model system. Bulk solvent effects were considered. Various alternative catalytic cycles were evaluated, and we found that one potential mechanism involves metal-catalyzed keto-enol tautomerization to form [(bpy)Rh(enol)](+) that adds hydrogen yielding a complex with axial and equatorial hydride ligands. The reaction continues via transfer of the hydrides to the enolic C=C bond thereby forming 2-propanol and regenerating the catalyst. Another potential catalytic cycle involves formation of [(bpy)Rh(acetone)(2)(H)(2)](+), which has a spectator solvent ligand, and initial transfer of the equatorial hydride to the carbonyl carbon of acetone. Other mechanisms involving hydrogen transfer to the acetone tautomer involved higher barriers. With an eye toward modeling multi-center catalysis, various model systems for the bpy ligand were considered. It was found that diimine (HN=CH-CH=NH) compares very well with bpy, whereas cis-1,2-diiminoethylene (H(2)C=N-CH=CH-N=CH(2)) yields a reaction profile very close to that of bpy. Finally, the system with two rhodium centers, [(diimine)Rh](2)(2+), was investigated. The results strongly suggest that an enol-type catalytic cycle occurs and that cooperativity between the two metal centers is responsible for the acceleration of the reaction in the monolayer system.

Journal Article↗
PubMed2004

Pre-extraction preparation (fresh, frozen, freeze-dried, or acetone powdered) and long-term storage of fruit and vegetable tissues: effects on antioxidant enzyme activity.

Activities of the antioxidant enzymes ascorbate peroxidase, catalase, dehydroascorbate reductase, glutathione reductase, guaiacol peroxidase, monodehydroascorbate reductase, and superoxide dismutase were assayed in honeydew (Cucumis melo L.) fruit and spinach (Spinacia oleracea L.) leaves either as fresh, frozen to -80 degrees C, frozen in liquid nitrogen, freeze-dried, or acetone powder, representing the various ways tissues are treated prior to enzyme extraction. Treated tissues were analyzed following treatment or stored for up to 8 weeks at -80 degrees C. Enzyme activities in fruit frozen with or without liquid nitrogen and leaves frozen with or without liquid nitrogen or freeze-dried were equal to those of fresh tissue. Enzyme activities in freeze-dried or acetone-powdered fruit and leaves and in acetone-powdered tissues were significantly higher or lower than those in fresh tissue. Enzyme activities in both tissues frozen with or without liquid nitrogen and stored for 8 weeks at -80 degrees C changed little; those in freeze-dried and acetone-powdered tissues, however, significantly increased/decreased over the same period. Fresh tissue should be used in antioxidant enzyme assays, but if storage is necessary, tissues should be placed directly into a -80 degrees C freezer.

Antioxidants↗
PubMed2005

Atmospheric pressure coated-wall flow-tube study of acetone adsorption on ice.

An atmospheric pressure variant of the coated-wall flow-tube technique in combination with a Monte Carlo simulation is presented. In a performance test of simple first-order wall loss, the Monte Carlo simulation, which uses a simplified model of transport in laminar flow, reproduced results of an analytical solution of the transport equations in a flow tube. This technique was then used to investigate the reversible adsorption of acetone on ice films between 203 and 223 K and a surface coverage of below 5% of a formal monolayer. Simulation of the experimental uptake traces allowed retrieving an adsorption enthalpy of -46 +/- 3 kJ mol(-1) for acetone on ice, which is in good agreement with other static and flow-tube methods. For the experimental conditions adopted here, the transport of acetone molecules along the ice film is governed by equilibrium thermodynamics. Therefore, the surface accommodation coefficient, S(0), and the preexponential factor, tau(0), for the activated desorption cannot be independently determined. These two main microphysical parameters describing partitioning can rather be estimated through their relation to the adsorption entropy. A first estimate for S(0) of acetone on ice in the range of 0.004-0.043 is given.

Journal Article↗
PubMed2005

Relative rate and product studies of the OH-acetone reaction.

The rate constants for the reaction of acetone (kH) and d6-acetone (kD) with OH radicals have been measured at atmospheric pressure over a range of temperatures by a relative rate method by using on-line mass spectrometry. The following Arrhenius expressions have been determined for these reactions (in units of cm(3) molecule(-1) s(-1)): k(H)(T) = (9.8 x 10(-13)) exp[-(484 +/- 44)/T] between 253 and 373 K, and kD(T) = (4.0 x 10(-13)) exp[-(755 +/- 89)/T] between 293 and 373 K. This is the first study to investigate the temperature dependence of kH and kD by using a relative rate method and confirms previous rate constants determined by absolute methods. Agreement of our rate constants with those determined in the absence of water suggests that the presence of water vapor has a minimal effect on the kinetics of this reaction under the conditions of our study. The observed kinetic isotope effect (kH/kD = 5.6 +/- 0.4 at 293 K) is evidence that H-atom abstraction occurs in the mechanism. The acetic acid yields of the reaction of OH with acetone and d6-acetone were also investigated by on-line mass spectrometry. Acetic acid yields show a negative temperature dependence that decreases from 0.12 at 273 K to 0.05 at 353 K. The yields of d3-acetic acid decrease from 0.20 at 283 K to 0.13 at 323 K. Kinetic modeling of our data suggests that 50-70% of the observed acetic acid in our system may be due to secondary reactions involving acetonoxy and HOx radical reactions. However, secondary chemistry cannot easily explain the observed formation of d3-acetic acid in the deuterated system, where about 90% of the observed d3-acetic acid is likely due to an OH-addition mechanism.

Journal Article↗
PubMed2006

Adsorption and solar light decomposition of acetone on anatase TiO2 and niobium doped TiO2 thin films.

Adsorption and solar light decomposition of acetone was studied on nanostructured anatase TiO2 and Nb-doped TiO2 films made by sol-gel methods (10 and 20 mol % NbO2.5). A detailed characterization of the film materials show that films contain only nanoparticles with the anatase modification with pentavalent Nb oxide dissolved into the anatase structure, which is interpreted as formation of substituted Nb=O clusters in the anatase lattice. The Nb-doped films displayed a slight yellow color and an enhanced the visible light absorption with a red-shift of the optical absorption edge from 394 nm for the pure TiO2 film to 411 nm for 20 mol % NbO2.5. In-situ Fourier transform infrared (FTIR) transmission spectroscopy shows that acetone adsorbs associatively with eta1-coordination to the surface cations on all films. On Nb-doped TiO2 films, the carbonyl bonding to the surface is stabilized, which is evidenced by a lowering of the nu(C=O) frequency by about 20 cm(-1) to 1672 cm(-1). Upon solar light illumination acetone is readily decomposed on TiO2, and stable surface coordinated intermediates are formed. The decomposition rate is an order of magnitude smaller on the Nb-doped films despite an enhanced visible light absorption in these materials. The quantum yield is determined to be 0.053, 0.004 and 0.002 for the pure, 10% Nb:TiO2, and 20%Nb:TiO2, respectively. Using an interplay between FTIR and DFT calculations we show that the key surface intermediates are bidentate bridged formate and carbonate, and H-bonded bicarbonate, respectively, whose concentration on the surface can be correlated with their heats of formation and bond strength to coordinatively unsaturated surface Ti and Nb atoms at the surface. The oxidation rate of these intermediates is substantially slower than the initial acetone decomposition rate, and limits the total oxidation rate at t>7 min on TiO2, while no decrease of the rate is observed on the Nb-doped films. The rate of degradation of key surface intermediates is different on pure TiO2 and Nb-doped TiO2, but cannot explain the overall lower total oxidation rate for the Nb-doped films. Instead the inferior photocatalytic activity in Nb-doped TiO2 is attributed to an enhanced electron-hole pair recombination rate due to Nb=O cluster and cation vacancy formation.

Journal Article↗
PubMed2004

Measurements of cavity ringdown spectroscopy of acetone in the ultraviolet and near-infrared spectral regions: potential for development of a breath analyzer.

We report a study on the cavity ringdown spectroscopy of acetone in both the ultraviolet (UV) and the near-infrared (NIR) spectral regions to explore the potential for development of a breath analyzer for disease diagnostics. The ringdown spectrum of acetone in the UV (282.4-285.0 nm) region is recorded and the spectrum is in good agreement with those obtained by other spectral techniques reported in the literature. The absorption cross-section of the C-H stretching overtone of acetone in the NIR (1632.7-1672.2 nm) is reported for the first time and the maximum absorption cross-section located at 1666.7 nm is 1.2 x 10(-21) cm(2). A novel, compact, atmospheric cavity with a cavity length of 10 cm has been constructed and implemented to investigate the technical feasibility of the potential instrument size, optical configuration, and detection sensitivity. The detection limit of such a mini cavity employing ringdown mirrors of reflectivity of 99.85% at 266 nm, where acetone has the strongest absorption, is approximately 1.5 ppmv based on the standard 3 criteria. No real breath gas samples are used in the present study. Discussions on the detection sensitivity and background spectral interferences for the instrument development are presented. This study demonstrates the potential of developing a portable, sensitive breath analyzer for medical applications using the cavity ringdown spectral technique.

Breath Tests↗
PubMed1964

A CONTROLED FIELD TRIAL OF THE EFFECTIVENESS OF ACETONE-DRIED AND INACTIVATED AND HEAT-PHENOL-INACTIVATED TYPHOID VACCINES IN YUGOSLAVIA.

In 1954-60 a Yugoslav Typhoid Commission showed in the first controlled field trial of typhoid vaccines, carried out in Osijek, Yugoslavia, that heat-phenol-inactivated typhoid vaccine gave a relatively high and long-lasting immunity. However, this liquid vaccine preparation was unstable and laboratory potency tests were inconclusive, and it was therefore decided that stable, dried, heat-killed, phenol-preserved vaccine be tested together with an acetone-inactivated and -dried vaccine in controlled field trials, supported in part by the World Health Organization, in Yugoslavia and British Guiana.This is report on the controlled trials organized in two Yugoslav towns, Bitola and Pristina. Three comparable groups were formed by random allocation of vaccines among 45 497 volunteers in the two towns. In each town one group received heat-phenol vaccine, the second group acetone-dried vaccine and the third (control) group tetanus toxoid. Two doses were given four weeks apart in the spring of 1960 and the vaccinated persons were followed up for 2 1/2 years. The effectiveness of the vaccines was measured by comparing typhoid morbidity rates in the three groups. It was found during an outbreak of typhoid fever in Pristina two years after primary vaccination that both the acetone-dried and the heat-phenol vaccines were effective, the former being superior.

Accident Prevention↗
PubMed1964

A CONTROLLED FIELD TRIAL OF ACETONE-DRIED AND INACTIVATED AND HEAT-PHENOL-INACTIVED TYPHOID VACCINES IN BRITISH GUIANA.

In 1960, some 72 000 schoolchildren in British Guiana participated in a controlled field trial of typhoid fever vaccines that was supported in part by the World Health Organization. The children were divided into three groups each receiving two doses, one of acetone-dried and inactivated vaccine, the second of heat-phenol-inactivated vaccine, and the third (control group) of tetanus toxoid. They were followed up over 3 1/2 years, during which time 99 cases of typhoid fever occurred in the control group, 6 in the acetone-dried vaccine group, and 26 in the heat-phenol vaccine group. Attack rates of the same order of magnitude were observed among 10 000 other children divided into the same three groups but given only one inoculation.The vaccines used were the same as those tested in a similar trial in Yugoslavia, and, although the attack rates in British Guiana were considerably lower in all groups than those in Yugoslavia, the findings in the two trials are in general agreement and indicate that acetone-dried vaccine confers greater protection than vaccine prepared from the same strains but inactivated by heat-phenol.

Accident Prevention↗
PubMed2003

Hemoglobin adducts from glycidamide: acetonization of hydrophilic groups for reproducible gas chromatography/tandem mass spectrometric analysis.

Acrylamide (AA) is a reactive compound widely used as an industrial chemical. It is also, as recently shown, present in heated foodstuffs. AA is known to cause tumors in rodents and is classified as probably carcinogenic to humans. The metabolite glycidamide (GA) is assumed to be the predominant genotoxic agent in AA exposure. Therefore, knowledge about in vivo doses of GA is essential for cancer risk assessment of exposure to AA. The in vivo dose of GA could be inferred from the level of the adduct formed by GA with N-terminal valine (GA-Val) in hemoglobin (Hb), detached as a pentafluorophenylthiohydantoin (PFPTH) and measured by gas chromatography/tandem mass spectrometric (GC/MS/MS) analysis. However, due to the highly polar character of the GA-Val-PFPTH derivative, it was found necessary to modify the method through further derivatization. This paper presents an evaluation of acetonization for derivatization of the adjacent bond;OH and bond;NH(2) groups in the adduct formed from GA. Good reproducibility was obtained. Also, acetonization improves the response and thus increases the sensitivity of the GC/MS/MS analysis of the PFPTH derivative of GA-Val. The sensitivity obtained is sufficient for studies of background adduct levels of GA in animals and in humans. Acetonization as a method for derivatization is robust and simple.

Acetone↗
PubMed1990

Enzymes involved in anaerobic degradation of acetone by a denitrifying bacterium.

The pathway of anaerobic acetone degradation by the denitrifying bacterial strain BunN was studied by enzyme measurements in extracts of anaerobic acetone-grown cells. An ADP- and MgCl2-dependent decarboxylation of acetoacetate was detected which could not be found in cell-free extracts of acetate-grown cells. It is concluded that free acetoacetate is formed by ATP-dependent carboxylation of acetone. Acetoacetate was converted into its coenzyme A ester by succinyl-CoA: acetoacetate CoA transferase, and cleaved by a thiolase into acetyl-CoA. The acetyl residue was completely oxidized in the citric acid cycle. The ADP-dependent decarboxylation of acetoacetate was inhibited by EDTA, but not by avidin. High myokinase activities led to equilibrium amounts of ATP, ADP, and AMP in the reaction mixtures, and prevented determination of the decarboxylase reaction stoichiometry, therefore.

Acetoacetates↗
PubMed1985

Cutaneous acetone depresses aqueous humor ascorbate in guinea pigs.

The purpose of the present investigation was to determine the concentration of ascorbate in the aqueous humor of guinea pigs over a 1-year period following the cutaneous application of a potential cataractogenic agent, acetone. Forty young guinea pigs received 15 ml acetone in small doses on their backs over a 6-week period; the ascorbate in their aqueous humor did not increase above 10 mg/100 ml during a 1-year test period. Ten control animals received only saline on their backs and the ascorbate concentrations steadily increased from 12 to over 18 mg/100 ml during the same time period. Three months after acetone treatment 12 animals (30%) developed cataracts and their ascorbate levels dropped to below 9 mg/100 ml after 1 year.

Acetone↗