[ACETIC ACID ESTERS (ACETATES)].
Explore the source record for details and available documents.
SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Investigation on 6 alpha-fluoro-9 alpha-chloro-16 alpha-methyl-delta 1,4-pregnadiene-11 beta-dihydroxy-3,20-dione-21-trimethylacetic acid (clocortolone trimethylacetic acid) are reported. The aim of the trial was to prove the penetration kinetics of the steriod into the skin. Three healthy female subjects took part in the investigations. They were treated with an oil-water emulsion of the substance on two spots on the back, after having observed alcohol abstinence. One of the treated spots was stripped after 30 min, the second after 60 min using the "Tesafilm" stripping method. The strips were then analysed gaschromatographically on the presence of clocortolone-trimethylacetic acid. It could be shown that the steroid penetrates into the skin up to the 12th-14th strips, building up a certain congestion of the substance at this time because of reaching the stratum corneum, as we suppose. At this place a depot is built of which probably only a very small or no permeation into the system occurs, as clocortolone could not be detected either in the subjects' serum nor in the urine.
Explore the source record for details and available documents.
A marked reduction in the motility of the human spermatozoa was observed when spermatozoa were incubated with 10 and 100 microgram of gossypol acetic acid for different time period at 37 degrees C; the motility was reduced from 83% to 4% after 210 minutes (P less than 0.001). A significant decrease in the activities of Ca++ and Mg++ activated ATPase in the spermatozoa was observed after gossypol treatment (P less than 0.005). Changes in the zinc++ concentration in the spermatozoa after gossypol treatment were, however, not significant. The present investigations suggest that inhibition of the sperm motility after gossypol treatment may be due to the inhibition of the ATPase activity in the spermatozoa.
The single crystal X-ray structure of the acetic acid solvate of trimesic acid shows the complete disruption of the hydrogen-bonded hexagonal networks of TMA by bonding to an acetic acid molecule.
A series of 9-oxo-9,10-dihydroacridine-4-acetic acids (acridone-4-acetic acids) were prepared by Jourdan-Ullmann condensation of 2-halobenzoic acids with 2-aminophenylacetic acids, followed by H2SO4-induced cyclodehydration of the resulting 2-[2-(carboxymethyl)phenylamino]benzoic acids. These were evaluated for their ability to induce haemorrhagic necrosis in transplanted colon 38 tumours in mice, using a short-term histology assay. The results broadly paralleled those seen previously for xanthenone-4-acetic acids, with 1-, 2- and 7-substitution being dystherapeutic, and substitution at the 5- and 6-positions by lipophilic groups increasing activity. While some analogues were as active as xanthenone-4-acetic acids in the histology assay and gave significant growth delays against colon 38 tumours in vivo, as a class the 9-oxo-9,10-dihydroacridine-4-acetic acids were generally less potent than the xanthenone-4-acetic acids.
De Ley, J. (State University, Ghent, Belgium), and S. Friedman. Deoxyribonucleic acid hybrids of acetic acid bacteria. J. Bacteriol. 88:937-945. 1964.-Deuterated N(15)-labeled deoxyribonucleic acid (DNA) from Acetobacter aceti (mesoxydans 4) forms hybrids with ordinary DNA from other species of this genus (A. xylinum, A. pasteurianus, A. estunensis, and possibly A. xylinoides) when the guanine plus cytosine base composition does not vary by more than 1 to 2%. Beyond this limit (A. aceti Ch31 and A. muciparus 5) no hybrids are formed. The hybrids are apparently derived from an asymmetrical part of the compositional distribution. The results lend strength to the concept of a genetic species rather than to a division of a genus into sharply separated species, based on small phenotypic differences. Taxonomic implications are discussed.
Infrared (IR) vibrational spectroscopy of acetic acid (A) neutral and ionic monomers and clusters, employing vacuum ultraviolet (VUV), 10.5 eV single photon ionization of supersonically expanded and cooled acetic acid samples, is presented and discussed. Molecular and cluster species are identified by time of flight mass spectroscopy: the major mass features observed are A(n)H(+) (n=1-9), ACOOH(+) (VUV ionization) without IR radiation present, and A(+) with both IR and VUV radiation present. The intense feature ACOOH(+) arises from the cleavage of (A)(2) at the beta-CC bond to generate ACOOH(+)+CH(3) following ionization. The vibrational spectrum of monomeric acetic acid (2500-7500 cm(-1)) is measured by nonresonant ionization detected infrared (NRID-IR) spectroscopy. The fundamentals and overtones of the CH and OH stretches and some combination bands are identified in the spectrum. Mass selected IR spectra of neutral and cationic acetic acid clusters are measured in the 2500-3800 cm(-1) range employing nonresonant ionization dip-IR and IR photodissociation (IRPD) spectroscopies, respectively. Characteristic bands observed at approximately 2500-2900 cm(-1) for the cyclic ring dimer are identified and tentatively assigned. For large neutral acetic acid clusters A(n)(n>2), spectra display only hydrogen bonded OH stretch features, while the CH modes (2500-2900 cm(-1)) do not change with cluster size n. The IRPD spectra of protonated (cationic) acetic acid clusters A(n)H(+) (n=1-7) exhibit a blueshift of the free OH stretch with increasing n. These bands finally disappear for n> or =6, and one broad and weak band due to hydrogen bonded OH stretch vibrations at approximately 3350 cm(-1) is detected. These results indicate that at least one OH group is not involved in the hydrogen bonding network for the smaller (n< or =5) A(n)H(+) species. The disappearance of the free OH stretch feature at n> or =6 suggests that closed cyclic structures form for A(n)H(+) for the larger clusters (n> or =6).
BACKGROUND: Transarterial chemoembolization (TACE) and percutaneous acetic acid injection (PAI) are effective treatments for hepatocellular carcinoma (HCC). We have conducted a prospective study to compare the efficacy of sequential TACE and PAI (TACE-PAI) versus repeated PAI therapy for HCC. PATIENTS AND METHODS: A total of 108 HCC patients with tumor size </=5 cm were enrolled. Fifty-three patients were treated with TACE-PAI and 55 patients were treated with PAI alone. RESULTS: Objective responses were achieved in 72 of 80 nodules (90%) in the TACE-PAI group compared with 51 of 62 nodules (82%) in the PAI group (P = 0.217) during 24 +/- 10 months of follow-up. Patients in the TACE-PAI group had a significantly lower cumulative tumor recurrence rate from the treated nodule (P = 0.004) or newly developed tumor elsewhere in liver (P = 0.010). Complete tumor necrosis in large (3-5 cm) HCCs was more frequently encountered in the TACE-PAI group (64% versus 37%; P = 0.034). There was no significant survival difference between the two groups with small (</=3 cm) HCC (P = 0.569), whereas PAI therapy was an independent poor prognostic predictor [relative risk 3.0 (95% confidence interval 1.2-7.6); P = 0.017] in the large HCC group. CONCLUSIONS: Sequential therapy with TACE and PAI is superior to repeated PAI alone for patients with large HCC.
In this study, we compared the growth properties and molecular characteristics of pyrroloquinoline quinone (PQQ)-dependent alcohol dehydrogenase (ADH) among highly acetic acid-resistant strains of acetic acid bacteria. Gluconacetobacter europaeus exhibited the highest resistance to acetic acid (10%), whereas Gluconacetobacter intermedius and Acetobacter pasteurianus resisted up to 6% of acetic acid. In media with different concentrations of acetic acid, the maximal acetic acid production rate of Ga. europaeus slowly increased, but specific growth rates decreased concomitant with increased concentration of acetic acid in medium. The lag phase of A. pasteurianus was twice and four times longer in comparison to the lag phases of Ga. europaeus and Ga. intermedius, respectively. PQQ-dependent ADH activity was twice as high in Ga. europaeus and Ga. intermedius as in A. pasteurinus. The purified enzymes showed almost the same specific activity to each other, but in the presence of acetic acid, the enzyme activity decreased faster in A. pasteurianus and Ga. intermedius than in Ga. europaeus. These results suggest that high ADH activity in the Ga. europaeus cells and high acetic acid stability of the purified enzyme represent two of the unique features that enable this species to grow and stay metabolically active at extremely high concentrations of acetic acid.
A series of (diacylvinylaryloxy)acetic acids was synthesized and tested in dogs for saluretic and diuretic activity. Several compounds exhibit a high order of activity, the most active being [2,3-dichloro-4-(2,2-diacetylvinyl)-phenoxy]acetic acid (3). This compound is about three times as potent as [2,3-dichloro-4-(2-methylenebutyryl)-phenoxy]acetic acid (ethacrynic acid) but is qualitatively similar in causing a prompt increase in the excretion of water and in the excretion of sodium and chloride ions in approximately equimolar amounts. Saturation of the double bond of 3 virtually abolishes activity lending support to the hypothesis that the saluresis induced by these compounds, like that of ethacrynic acid, is related at least in part to a chemical reaction with protein-bound sulfhydryl groups. Four mercaptan adducts of 3 were prepared; these probably function as prodrugs in producing saluresis. The adduct with mercaptoacetic acid is as active as 3 itself.
Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid. Indoleacetic acid (IAA), 4-chloro-IAA (4-Cl-IAA), and 5-Cl-IAA were metabolized to different extents by strains 61A24 and 110. Metabolites were isolated and analyzed by high-performance liquid chromatography and conventional mass spectrometry (MS) methods, including MS-mass spectroscopy, UV spectroscopy, and high-performance liquid chromatography-MS. The identified products indicate a novel metabolic pathway in which IAA is metabolized via dioxindole-3-acetic acid, dioxindole, isatin, and 2-aminophenyl glyoxylic acid (isatinic acid) to anthranilic acid, which is further metabolized. Degradation of 4-Cl-IAA apparently stops at the 4-Cl-dioxindole step in contrast to 5-Cl-IAA which is metabolized to 5-Cl-anthranilic acid.
Explore the source record for details and available documents.
Indole-3-acetic acid (IAA) and 2-(indol-3-ylmethyl)indol-3-yl acetic acid were identified in lipid extracts of Sulfolobus acidocaldarius; they occurred at concentrations of 0.57 and 0.59 mumol/g (dry weight), respectively. The amount of IAA found in these cells is more than a thousand times greater than that found in a typical extract of a plant in which IAA serves as a plant growth hormone. Neither of these compounds was detected in the other archaebacteria that were analyzed; these included Sulfolobus sulfataricus, Halobacterium salinarium, and several strains of methanogenic bacteria. This is the first report of the natural occurrence of 2-(indol-3-ylmethyl)indol-3-yl acetic acid.
Explore the source record for details and available documents.