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PubMed1992

[The ovarian response and fertility in cows with acidosis induced by acetic acid].

The effects of acetic acid administered at an amount of 300 to 600 g (5 to 10 mol) to the rumen of breeding cows, were investigated on ovulation, conception and progesterone levels in the blood and milk of cows with cloprostenol-induced (Oestrophan Spofa) oestrus at a dose of 500 micrograms i.m. In the group of 15 cows exposed to the acetic acid load five cows got in calf after the first insemination (33.3%), and 12 cows (80.0%) after all inseminations in 37.6 days after cloprostenol administration, with the insemination index 1.67 (Tab. I). In the control group (five cows) four cows (80.0%) got in calf after the first insemination, in total all five breeding cows got in calf in 20.6 days after cloprostenol administration, with the insemination index 1.2. In the experimental group of 15 cows a clinical examination of ovaries on day 7 after insemination revealed ovulation disorders in eight cows, that means in 53.3% of the animals (Tab. II). No ovulation disorders were observed in the control group of five cows. Progesterone levels in the blood showed high variability (Tab. III). In the group of cows administered acetic acid they were by more than a half lower (1.49; 0.67; 1.53 per ml) on days 7, 14 and 21 after insemination in comparison with the control group (3.35; 2.5; 3.38 ng per ml). The average progesterone levels in milk (Tab. IV) were 1.27 and 1.53 on day 7, 6.74 and 7.27 on day 14 and 3.52 and 11.85 ng per ml on day 21, respectively, the higher values apply to the control. It was not possible to evaluate reliably from the progesterone levels in the blood and milk if ovulation took place and if the corpus luteum was developing (Tab. V and VI). The clinical control of ovaries on days 7 and 8 after oestrus and insemination was more reliable to determine the ovulation disorders than the progesterone determination in the blood and milk of cows.

Acetates↗
PubMed1986

Automated analysis of homovanillic acid and 5-hydroxyindole-3-acetic acid in biological fluids by coupled-column liquid chromatography and dual coulometric-amperometric detection.

Homovanillic acid (HVA) and 5-hydroxyindole-3-acetic acid (5-HIAA) were determined by direct injection of plasma, urine and cerebrospinal fluid (CSF) into a liquid chromatographic system comprising three columns, one packed with an anion-exchange gel and two with reversed-phase material. The acidic compounds were isolated by anion-exchange on the first column, enriched on the second and separated by reversed-phase chromatography on the last column. 5-HIAA and HVA were detected by coulometry and amperometry on two working electrodes coupled in series, giving limits of determination in plasma of 4 and 5 nmol l(-1) respectively. Endogenous plasma, urine and CSF-levels were determined with a precision (RSD) of 2-4%. 3-Methoxy-4-hydroxyphenylpropionic acid was identified in normal plasma and urine.

Journal Article↗
PubMed2000

The potent, selective mGlu2/3 receptor agonist LY379268 increases extracellular levels of dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acid, and 5-hydroxyindole-3-acetic acid in the medial prefrontal cortex of the freely moving rat.

Previous work has shown that the potent, selective metabotropic glutamate mGlu2/3 receptor agonist LY379268 acts like the atypical antipsychotic clozapine in behavioral assays. To investigate further the potential antipsychotic actions of this agent, we examined the effects of LY379268 using microdialysis in awake, freely moving rats, on extracellular levels of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and 5-hydroxyindole-3-acetic acid (5-HIAA) in rat medial prefrontal cortex. Systemic LY379268 increased extracellular levels of dopamine, DOPAC, HVA, and 5-HIAA in a dose-dependent, somewhat delayed manner. LY379268 (3 mg/kg s.c. ) increased levels of dopamine, DOPAC, HVA, and 5-HIAA to 168, 170, 169, and 151% of basal, respectively. Clozapine (10 mg/kg) also increased dopamine, DOPAC, and HVA levels, with increases of 255, 262, and 173%, respectively, but was without effect on extracellular 5-HIAA levels by 3 mg/kg LY379268 were reversed by the selective mGlu2/3 receptor antagonist LY341495 (1 mg/kg). Furthermore, LY379268 (3 mg/kg)-evoked increases in DOPAC and HVA were partially blocked and the increase in 5-HIAA was completely blocked by local application of 3 microM tetrodotoxin. Therefore, we have demonstrated that mGlu2/3 receptor agonists activate dopaminergic and serotonergic brain pathways previously associated with the action of atypical antipsychotics such as clozapine and other psychiatric agents.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1975

Homovanillic acid and 5-hydroxyindole-acetic acid in the csf of patients after a severe head injury. I. Lumbar csf concentration in chronic brain post-traumatic syndromes.

Lumbar CSF concentrations of homovanillic acid (HVA) and 5-hydroxyindole-acetic acid (5HIAA) have been determined in ten patients suffering from chronic brain post-traumatic syndromes, at various length of time after the brain trauma. Lower concentrations of HVA (mean 21 +/- 14 mug/ml) compared to controls (mean 46 +/- 10 mug/ml) was observed in 7 cases; 5HIAA levels were within normal values. The 5HIAA/HVA ratio (1.59 +/- 0.66) was significantly higher (p less than 0.001) than the one recorded in controls (0.66 +/- 0.10). Monitoring of lumbar HVA and 5HIAA over time, before, during and after L-dopa treatment, revealed interesting correlations between modification of clinical picture and the levels of monoamines acid metabolites. The data indicate a profound alteration of brain monoamines in chronic syndromes following a severe head injury and suggest that measurements of lumbar HVA and 5HIAA in these patients may be of euristic and diagnostic value.

Adolescent↗
PubMed1975

Homovanillic acid and 5-hydroxyindole-acetic acid in the csf of patients after a severe head injury. II. Ventricular csf concentrations in acute brain post-traumatic syndromes.

Ventricular concentrations of homovanillic acid (HVA) and 5-hydroxyindole-acetic acid (5HIAA) were measured in 7 patients a few days after a severe traumatic brain injury. Both acid metabolites were elevated in respect to control patients values, however, the rise was more consistent for 5HIAA (258 +/- 86 ng/ml) with a 5HIAA/HVA ratio of 0.85 +/- 0.35. The data support previous hypothesis on the profound involvement of serotoninergic structures in the early stages of acute traumatic brain syndromes and on the role of 5HT in maintaining edema and vasospasm.

Adolescent↗
PubMed1973

Shigella flexneri inhibition by acetic acid.

The degree of Shigella flexneri inhibition by acetic acid in a chemically defined medium was dependent upon the concentration of undissociated acetic acid in the medium. Under the conditions of the experiments, the critical concentration of undissociated acetic acid that completely inhibited S. flexneri multiplication was approximately 0.0018 M. Adjustment of the medium from pH 6.0 to 7.0 after incubation, which reduced the concentration of undissociated acid 10-fold, completely reversed inhibition, and S. flexneri attained a viable population equivalent to its population in medium without acetic acid. The effects of acetic acid on cellular processes were also studied. The acid interfered with the intracellular accumulation of glucose and glutamic acid but did not interfere with the accumulation of phosphate. The glucose analogue 3-o-methyl-D-glucose, which is taken up by S. flexneri but not metabolized, was used to determine if inhibition resulted from interference with permeation or interference with intracellular accumulation through inhibition of glucose metabolism. Acetic acid did not interfere with the uptake of the glucose analogue by S. flexneri, indicating that inhibition probably involves interference with metabolism. Further evidence for this conclusion was obtained from respiration studies with cell-free extracts in the presence and absence of acetic acid. Inhibition of oxygen uptake by acetic acid in the absence of a permeability barrier suggested a metabolic block rather than interference with permeation. The inhibition of oxygen uptake by cell-free extracts occurred at both pH 6.0 and 7.0, indicating that the degree of dissociation of the acid is unimportant regarding interference with metabolism by intracellular material. The degree of dissociation is important, however, regarding uptake of acetic acid by S. flexneri. Whole cells were more permeable to the undissociated form of acetic acid than to the dissociated form. The data indicate that acetic acid, when taken up by S. flexneri, interferes with the metabolism of glucose by the cells.

Acetates↗
PubMed1990

(Pyrimidinyloxy)acetic acids and pyrimidineacetic acids as a novel class of aldose reductase inhibitors.

Pyrimidineacetic acids and (pyrimidinyloxy)acetic acids were synthesized by alkylation, with methyl bromoacetate or tert-butyl bromoacetate as alkylating agents. Alkylation reaction at the nitrogen or oxygen atom for different substrates was found to be solvent dependent. N-Alkylation was favored in ethereal solvent, e.g., tetrahydrofuran and dimethoxyethane, whereas O-alkylation was predominant in dimethylformamide. These compounds were tested in vitro to determine their ability to inhibit bovine lens aldose reductase. Selected compounds were assayed in vivo, in a 4-day galactose-fed rat model. The decrease in galactitol from the control was determined in lens, nerve, and diaphragm. Several of the 6-oxopyrimidine-1-acetic acids and (pyrimidinyl-4-oxy)acetic acids were found to be potent inhibitors of bovine lens aldose reductase. A study was also undertaken to determine in vitro the transport behavior of selected compounds in the isolated rat sciatic nerve. A discussion of the structure-activity relationship of this class of compounds with reference to their intrinsic biochemical activity is reported. It is concluded, in general, that ability of a compound to penetrate the tissue membrane plays an important role in the genesis of in vivo lens aldose reductase (LAR) inhibitory activity.

Acetates↗
PubMed1992

Synthesis and aldose reductase inhibitory activity of pyridazine derivatives possessing acetic acid group.

N-acetic acid and S-acetic acid derivatives of 5-arylidene pyridazines were synthesized for evaluation as new aldose reductase inhibitors. Intrinsic activity for each compound was assessed by measuring inhibition of enzymatic activity in an isolated pig lens enzyme preparation. All prepared compounds exhibited a significant in vitro aldose reductase inhibitory effect (10(-5) M less than or equal IC50 less than or equal to 10(-4) M). It was found that lipophilicity was important in increasing activity. Furthermore, this activity (log 1/IC50) could be correlated directly to a lipophilic parameter (log kw) for the whole data set.

Acetates↗
PubMed1995

Effect of acetic acid on xylose fermentation to xylitol by Candida guilliermondii.

The effect of acetic acid concentration on xylose-fermentation to xylitol by Candida guilliermondii FTI 20037 was evaluated in semisynthetic medium containing different concentrations of the acid. Increasing acetic acid concentration up to 1.0 g/l favored xylitol yield and productivity, with maximum values of 0.82 g/g and 0.57 g/l.h, respectively. The presence of acetic acid reduced cell production at all concentration. Furthermore, acetic acid was assimilated by the yeast together with the sugars and was depleted from the medium at concentrations of less than 3.0 g/l. The ability of this yeast to assimilate acetic acid suggests that these cells act as agents of medium detoxification. This behavior may lead to a viable microbiological process of xylitol production by C. guilliermondii FTI 20037 using xylose-rich lignocellulosic hydrolysates in which acetic acid is commonly present, causing inhibition of fermentative activity.

Acetates↗
PubMed1990

[The effect of acetic acid and furfural on yeast growth].

Acetic acid and furfural are normal components of the yeast hydrolysates. The influence of acetic acid in different concentrations (from 2 to 10 g/dm3) and furfural (from 0.2 to 0.8 g/dm3) on the growth of 8 yeast strains from the genus Candida under cultivation in synthetic nutrient media has been studied. It was established that some yeast strains absorb acetic acid better at pH 4.0-5.0, while others--only at pH 6.0 and at different concentrations of the acid in the nutrient media. Acetic acid in concentrations from 2 to 4 g/dm3 suppresses growth entirely in some strains, while in others growth was established. Acetic acid in concentrations over 8 g/dm3 inhibits growth in all 8 strains of the studied yeasts. Furforal in concentration to 0.4 g/dm3 in the synthetic nutrient media inhibits the growth in the 8 strains to a certain extent, while in concentration over 8 g/dm3 it stops the growth in all 8 yeast strains.

Acetates↗
PubMed2001

(+/-)-1-Tetralone-3-carboxylic acid and (+/-)-1-tetralone-2-acetic acid: hydrogen bonding in two gamma-keto acids.

The crystal structure of (+/-)-4-oxo-1,2,3,4-tetrahydronaphthalene-2-carboxylic acid (C(11)H(10)O(3)) involves projection of the carboxyl group nearly orthogonal to the aromatic plane and hydrogen bonding of the acid groups by centrosymmetric pairing across the a edge and the center of the chosen cell [O...O = 2.705 (2) A]. Intermolecular C--H...O==C close contacts to translationally related molecules are found for both the ketone (2.55 A) and the acid (2.67 A). In (+/-)-1-oxo-1,2,3,4-tetrahydronaphthalene-2-acetic acid (C(12)H(12)O(3)), the aggregation involves centrosymmetric carboxyl dimers mutually hydrogen bonded across the bc face and the a edge of the chosen cell [O...O = 2.674 (2) A]. A 2.60 A close C--H...O==C contact is found to the carboxyl group of centrosymmetrically related molecule.

Journal Article↗
PubMed1984

[The antianaphylactic effect of derivatives of 4-oxoquinazoline, 4-oxoquinazol-3-yl-benzoic acid and 4-oxoquinazol-3-yl-acetic acid in the rat].

Derivatives substituted at position 2 of 4-oxochinazolin as well as derivates of oxochinazolin-3-yl-benzoic acid and 4-oxochinazolin-3-yl-acetic acid had been tested for their antianaphylactic activities in the passive (PCA) and/or active cutaneous anaphylaxis (ACA) in rats. At i.p. administration (ACA) or intracutaneous (i.c.) administration (PCA) most of the derivates displayed a moderate antianaphylactic activity which et best could be compared to the theophylline activity. Only the free acids of the 4-oxochinazolin-3-yl-acetic acid derivatives were active at i.c. administration. All compounds tested remained inactive at p.o. administration.

Anaphylaxis↗
PubMed2004

Selective extraction of acetic acid from the fermentation broth produced by Mannheimia succiniciproducens.

Acetic acid is by-product from fermentation processes for producing succinic acid using Mannheimia succiniciproducens . To obtain pure succinic acid from the final fermentation broth, acetic acid was selectively removed based on the different extractability of succinic acid and acetic acid with pH using tri-n-octylamine (TOA) as extractant. When successive batch extractions were performed using 0.25 mol TOA kg(-1) dissolved in 1-octanol at pH 5, the mol ratio of succinic acid to acetic acid before extraction was 4.9 and the final ratio after the fourth batch was 9.4.

Acetic Acid↗
PubMed1984

Effects of gibberellic Acid on endogenous indole-3-acetic Acid and indoleacetyl aspartic Acid levels in a dwarf pea.

Two-week-old dwarf peas (Pisum sativum cv Little Marvel) were sprayed with gibberellic acid (GA(3)), and after 3 or 4 days the upper stem and young leaf samples were analyzed for indole-3-acetic acid (IAA) and indole-3-acetyl aspartic acid by an isotope dilution high performance liquid chromatography method. GA(3) increased IAA levels as much as 8-fold and decreased indole-3-acetyl aspartic acid levels.

Journal Article↗