Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PROPIONATES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,171 records · Page 65Linked to original sources
PubMed1987

Influence of solvent on the availability of testosterone propionate from oily, intramuscular injections in the rat.

The suggestion that the biological response to an oily intramuscular injection of testosterone ester is regulated by rapid accumulation of the steroid in body fat, followed by a slow release, has been tested by comparing the release rates of 14C-labelled testosterone propionate from different solvents following intramuscular injection into rats. Disappearance from the injection site was rectilinearly related to in-vitro partition coefficients, but elimination of radioactivity in urine and faeces was significantly longer, and the same for all four solvents. Testosterone and testosterone propionate were found in equal concentration in body fat, 2 and 3 days after injection, but their concentrations were too low to form an effective depot. It is suggested that the delay in release, and the independence of the delay on the nature of the solvent is a consequence of biliary recycling of testosterone.

Adipose Tissue↗
PubMed2003

Group II metabotropic and alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA)/kainate glutamate receptors regulate the deficit in brain reward function associated with nicotine withdrawal in rats.

This study investigated the role of ionotropic and metabotropic glutamate receptors in the deficits in brain reward function, as measured by elevations in intracranial self-stimulation (ICSS) reward thresholds, associated with nicotine withdrawal. The group II metabotropic glutamate (mGluII) receptor agonist LY314582 [a racemic mixture of LY354740 ([+]-2-aminobicyclo[3.1.0]hexane-2,6-dicarboxylic acid])] (2.5-7.5 mg/kg) precipitated withdrawal-like elevations in ICSS thresholds, a sensitive measure of reward function, in nicotine-dependent but not control rats. LY314582 did not affect response latencies, a measure of performance in the ICSS paradigm. Bilateral microinfusion of LY314582 (10-100 ng/side) into the ventral tegmental area likewise precipitated dose-dependent threshold elevations in nicotine-dependent rats. Furthermore, a single injection of the mGluII receptor antagonist LY341495 (2S-2-amino-2-[1S,2S-2-carboxycyclopropan-1-yl]-3-[xanth-9-yl]propionic acid) (1 mg/kg) attenuated the threshold elevations observed in rats undergoing spontaneous nicotine withdrawal. mGluII receptors are primarily located on glutamatergic terminals throughout the mesocorticolimbic system, where they act as inhibitory autoreceptors. To investigate whether mGluII receptors contributed to nicotine withdrawal by decreasing glutamatergic transmission, we next examined whether direct blockade of postsynaptic glutamate receptors precipitated withdrawal-like reward deficits in nicotine-dependent rats. The alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA)/kainate receptor antagonist 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo(f)quinoxaline (NBQX; 0.01-1 mg/kg) precipitated withdrawal-like threshold elevations in nicotine-dependent but not control rats, whereas 6-methyl-2-[phenylethynyl]-pyridine (MPEP; 0.01-3 mg/kg) and dizocilpine (MK-801; 0.01-0.2 mg/kg), antagonists at metabotropic glutamate 5 and N-methyl-d-aspartate receptors, respectively, did not. Overall, these data demonstrate that mGluII receptors play an important role in the reward deficits associated with nicotine withdrawal. Furthermore, it is likely that mGluII receptors generate this reward deficit, at least in part, by decreasing glutamate transmission at AMPA/kainate receptors.

Animals↗
PubMed1998

Antagonist properties of a phosphono isoxazole amino acid at glutamate R1-4 (R,S)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid receptor subtypes.

The activity of the (R, S)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA) receptor antagonist, (R,S) -2-amino-3-[5-tert-butyl-3-(phosphonomethoxy)-4-isoxazolyl] propionic acid (ATPO), at recombinant ionotropic glutamate receptors (GluRs) was evaluated using electrophysiological techniques. Responses at homo- or heterooligomeric AMPA-preferring GluRs expressed in human embryonic kidney (HEK) 293 cells (GluR1-flip) or Xenopus laevis oocytes (GluR1-4-flop or GluR1-flop + GluR2) were potently inhibited by ATPO with apparent dissociation constants (Kb values) ranging from 3.9 to 26 microM. A Schild analysis for kainate (KA)-activated GluR1 receptors showed ATPO to have a KB of 8.2 microM and a slope of unity, indicating competitive inhibition. The antagonism by ATPO at GluR1 was of similar magnitude at holding potentials between -100 mV and +20 mV. In contrast, ATPO (<300 microM), does not inhibit responses to kainate at homomeric GluR6 or heterooligomeric GluR6/KA2 expressed in HEK 293 cells but activated GluR5 and GluR5/KA2 expressed in X. laevis oocytes. ATPO produced <15% inhibition at the maximal concentration (300 microM) of current responses through NR1A + NR2B receptors expressed in X. laevis oocytes. Thus, ATPO shows a unique pharmacological profile, being an antagonist at GluR1-4 and a weak partial agonist at GluR5 and GluR5/KA2.

Animals↗
PubMed1981

Metabolic Activity of Fatty Acid-Oxidizing Bacteria and the Contribution of Acetate, Propionate, Butyrate, and CO(2) to Methanogenesis in Cattle Waste at 40 and 60 degrees C.

The quantitative contribution of fatty acids and CO(2) to methanogenesis was studied by using stirred, 3-liter bench-top digestors fed on a semicontinuous basis with cattle waste. The fermentations were carried out at 40 and 60 degrees C under identical loading conditions (6 g of volatile solids per liter of reactor volume per day, 10-day retention time). In the thermophilic digestor, acetate turnover increased from a prefeeding level of 16 muM/min to a peak (49 muM/min) 1 h after feeding and then gradually decreased. Acetate turnover in the mesophilic digestor increased from 15 to 40 muM/min. Propionate turnover ranged from 2 to 5.2 and 1.5 to 4.5 muM/min in the thermophilic and mesophilic digestors, respectively. Butyrate turnover (0.7 to 1.2 muM/min) was similar in both digestors. The proportion of CH(4) produced via the methyl group of acetate varied with time after feeding and ranged from 72 to 75% in the mesophilic digestor and 75 to 86% in the thermophilic digestor. The contribution from CO(2) reduction was 24 to 29% and 19 to 27%, respectively. Propionate and butyrate turnover accounted for 20% of the total CH(4) produced. Acetate synthesis from CO(2) was greatest shortly after feeding and was higher in the thermophilic digestor (0.5 to 2.4 muM/min) than the mesophilic digestor (0.3 to 0.5 muM/min). Counts of fatty acid-degrading bacteria were related to their turnover activity.

Journal Article↗
PubMed1985

Methanogenesis in an Upflow Anaerobic Sludge Blanket Reactor at pH 6 on an Acetate-Propionate Mixture.

High-rate anaerobic digestion can be applied in upflow anaerobic sludge blanket reactors for the treatment of various wastewaters. In upflow anaerobic sludge blanket reactors, sludge retention time is increased by a natural immobilization mechanism (viz. the formation of a granular type of sludge). When this sludge is cultivated on acid-containing wastewater, the granules mainly consist of an acetoclastic methanogen resembling Methanothrix soehngenii. This organism grows either in rods or in long filaments. Attempts to cultivate a stable sludge consisting predominantly of Methanosarcina sp. on an acetate-propionate mixture as substrate by lowering the pH from 7.5 during the start-up to approximately 6 failed. After 140 days of continuous operation of the reactor a filamentous organism resembling Methanothrix soehngenii prevailed in the sludge. The specific methanogenic activity of this sludge on acetate-propionate was optimal at pH 6.6 to 6.8 and 7.0 to 7.2, respectively.

Journal Article↗
PubMed1987

Effects of pH, Temperature, and Nutrients on Propionate Degradation by a Methanogenic Enrichment Culture.

Enrichment cultures were used to determine the conditions promoting fastest methanogenic propionate degradation and growth by adapting the cultures to various physical and chemical conditions and measuring the specific growth rate. We found that the fastest growth of propionate oxidizers occurred at pH 6.8 to 8.5 and 32 to 45 degrees C. Acetate-degrading populations showed narrower optima for fastest growth (pH 6.8 to 7.2 and 37 to 43 degrees C). Enrichment cultures grew as well in minimal medium as in complex medium, although individual microbial populations appeared to require growth factors which could be met by cross-feeding.

Journal Article↗
PubMed1993

Complete oxidation of propionate, valerate, succinate, and other organic compounds by newly isolated types of marine, anaerobic, mesophilic, gram-negative, sulfur-reducing eubacteria.

Anaerobic enrichment cultures with either propionate, succinate, lactate, or valerate and elemental sulfur and inocula from shallow marine or deep-sea sediments were dominated by rod-shaped motile bacteria after three transfers. By application of deep-agar dilutions, five eubacterial strains were obtained in pure culture and designated Kyprop, Gyprop, Kysw2, Gylac, and Kyval. All strains were gram negative and grew by complete oxidation of the electron donors and concomitant stoichiometric reduction of elemental sulfur to hydrogen sulfide. The isolates used acetate, propionate, succinate, lactate, pyruvate, oxaloacetate, maleate, glutamate, alanine, aspartate, and yeast extract. All isolates, except strain Gylac, used citrate as an electron donor but valerate was oxidized only by strain Kyval. Fumarate and malate were degraded by all strains without an additional electron donor or acceptor. Kyprop, Gyprop, and Gylac utilized elemental sulfur as the sole inorganic electron acceptor, while Kysw2 and Kyval also utilized nitrate, dimethyl sulfoxide, or Fe(III)-citrate as an electron acceptor.

Journal Article↗
PubMed1995

Interspecies Electron Transfer during Propionate and Butyrate Degradation in Mesophilic, Granular Sludge.

Granules from a mesophilic upflow anaerobic sludge blanket reactor were disintegrated, and bacteria utilizing only hydrogen or formate or both hydrogen and formate were added to investigate the role of interspecies electron transfer during degradation of propionate and butyrate. The data indicate that the major electron transfer occurred via interspecies hydrogen transfer, while interspecies formate transfer may not be essential for interspecies electron transfer in this system during degradation of propionate and butyrate.

Journal Article↗
PubMed1994

Fluticasone propionate for asthma prophylaxis.

Inhaled corticosteroids have an essential role in the management of many patients with asthma, improving control and reducing the need for oral corticosteroids. Used in conventional dosage inhaled corticosteroids are very safe; in high dosage systemic effects are more evident. Fluticasone propionate (Flixotide--Allen & Hanburys), a new inhalation corticosteroid, is promoted as being more potent than conventional preparations (beclomethasone dipropionate and budesonide) and less likely to cause systemic effects. Is this claim justified and what is the place of fluticasone propionate in asthma prophylaxis?

Administration, Topical↗
PubMed1991

A pilot study of fluticasone propionate in untreated coeliac disease.

Although gluten withdrawal is likely to remain the mainstay of treatment for adult coeliac disease, many patients find the diet inconvenient and unpalatable and compliance among asymptomatic patients is often poor. Oral corticosteroids have been used for patients who seem to be resistant to gluten withdrawal but preparations with low systemic bioavailability might be preferable. We have given a new glucocorticoid (fluticasone propionate) to 12 adults with untreated coeliac disease for six weeks while they were on a normal diet. One patient defaulted and one suffered a relapse in a pre-existing neoplasm. Excluding these, there was an improvement of symptoms, a mean weight gain of 2 kg, and a rise in albumin of 5.4 g/l. There was a significant improvement in the lactulose/mannitol excretion ratio (p less than 0.05) and in all histological variables examined in paired biopsy specimens (surface and crypt intraepithelial lymphocyte/enterocyte and goblet cell/enterocyte ratios and enterocyte height, p less than 0.01 or better). In six paired specimens sucrase and alkaline phosphatase activity increased in all (p less than 0.05) and lactase in five of six. No appreciable side effects were observed, but two patients had suppressed cortisol values and synacthen responses at six weeks. A further three, with normal pretrial results, had a blunted tetracosactrin response at six weeks. Fluticasone propionate seems worthy of further assessment in the treatment of coeliac disease as an adjunct to gluten withdrawal.

Adult↗
PubMed1965

Detection by paper chromatography of imidazoles, including hydantoin-5-propionic acid, in urine after histidine dosage.

Simple paper chromatography of urine obtained in the Figlu test has been found satisfactory for determining excess excretion of the imidazole metabolites of histidine. It has been confirmed that examination for these in addition to formiminoglutamic acid is necessary for a full assessment of this test. When excretion of the latter is not abnormal in folic-acid and/or vitamin B(12) deficiency, that of urocanic acid, a glycine conjugate of urocanic acid and/or imidazole propionic acid, is usually raised. An abnormally high excretion of hydantoin-5-propionic acid after histidine has also been found in these deficiencies, and its estimation may be of additional use in the evaluation of the Figlu test.

Adult↗
PubMed2002

Effects of fluticasone propionate on inflammatory cells in COPD: an ultrastructural examination of endobronchial biopsy tissue.

BACKGROUND: Inhaled corticosteroids (ICS) markedly reduce bronchial mucosal inflammation in asthma but whether they have an anti-inflammatory effect in airway tissue in chronic obstructive pulmonary disease (COPD) is unknown. METHODS: A study of endobronchial biopsy samples was conducted as part of a double blind, placebo controlled, randomised trial of parallel design. Patients had mild to moderately severe COPD (FEV(1) 25-80% of predicted) and were given 3 months treatment with ICS, fluticasone propionate (FP; 500 micro g twice daily, n=14) or placebo (n=10). Biopsy tissue taken at baseline and after treatment was examined by transmission electron microscopy to count the numbers of all ultrastructurally distinct inflammatory cells. RESULTS: Compared with their baseline values, FP resulted in a significant decrease (on average 65%) in the numbers of mucosal mast cells (median 7.8 (range 1-33) v 2.8 (1-14), p<0.05). The reductive effect of FP held true when the post-treatment values of the placebo and FP groups were compared: 8.8 (1-24) v 2.8 (1-14) (p<0.05). Unexpectedly, there were significantly more neutrophils in the FP than in the placebo group: 4.0 (0-23) v 1.7 (0-8), respectively (p<0.05). There were no alterations to other cell types including mononuclear cells. Symptoms markedly improved in the patients treated with FP for 3 months. CONCLUSION: Fluticasone propionate given for 3 months to patients with COPD has selective effects on the inflammatory cells in the bronchial mucosa: the reduction in mast cell numbers may account for the improvement in symptoms over this time.

Aged↗
PubMed2004

Biological availability of inhaled fluticasone propionate in horses.

Healthy horses received aerosolised, intranasal or oral doses of 3 mg of fluticasone propionate evenly divided over morning and evening treatments for seven days. The bioavailability of the drug was determined in terms of the suppression of the endogenous cortisol concentrations in the horses during the period of treatment. The horses which received the aerosolised drug had significantly lower concentrations of endogenous cortisol on days 5 and 8 than the horses which received aerosolised placebo. The horses which received nasal and oral doses of fluticasone propionate showed no significant changes in their endogenous cortisol concentrations.

Administration, Inhalation↗
PubMed1982

Effects of testosterone propionate on hindlimb-immobilized rats.

Forty albino male rats were randomly divided into 4 groups of 10. Group I served as the nonimmobilized control and received daily placebo injections of sesame oil. The rats in group II were castrated, their hindlimbs were immobilized using a plaster cast, and they received daily injections of sesame oil. The group III rats were also castrated and casted but received a daily injection of 5 mg testosterone propionate. The animals in group IV were not castrated but were casted and received daily testosterone propionate injections. The duration of each treatment was 15 days for each rat. The gastrocnemius, quadriceps, soleus, and cardiac muscles were weighed after treatment. O2 consumption capacity (QO2), citrate synthase activities, and percentages of water were measured in the gastrocnemius, quadriceps, and cardiac tissues. Along with the atrophy of muscle and reduction in body size, the immobilization significantly reduced the aerobic capacity of affected muscle groups and cardiac tissue. The greatest reductions in body weight, muscle size, heart size, and QO2 were seen in the castrated group that received only placebo injections of sesame oil. The anticatabolic effects of the anabolic steroid were evident in groups III and IV. The results indicate that hindlimb immobilization not only causes severe atrophy in those muscles immobilized but has an overall catabolic effect on the animal. Testosterone, or the lack of it, can significantly affect the amount of muscle atrophy.

Animals↗
PubMed2002

Fluticasone propionate downregulates nasal fibroblast functions involved in airway inflammation and remodeling.

BACKGROUND: Besides being highly effective in the treatment of allergic and nonallergic rhinitis with eosinophilia, intranasal corticosteroids appear to be useful in reducing nasal polypoid lesions and the likelihood of polyp recurrence after surgery. We evaluated the ability of fluticasone propionate to downregulate fibroblast functions related to nasal inflammation and remodeling. METHODS: Primary nasal polyp tissue-derived fibroblasts were stimulated with tumor necrosis factor (TNF)-alpha or interleukin (IL)-4 or basic fibroblast growth factor (bFGF) in the presence of fluticasone propionate (0.1-100 nM). Fibroblast proliferation, intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 expression and eotaxin release were then evaluated. RESULTS: As compared with unstimulated cultures, a significant increase in fibroblast proliferation was observed when the cells were stimulated with bFGF (p < 0.05), but not with TNF-alpha or IL-4 (p > 0.05). TNF-alpha induced an upregulation of ICAM-1 expression (p < 0.05), which was not seen in fibroblasts cultured in the presence of IL-4 or bFGF. No changes in VCAM-1 expression were induced by TNF-alpha, IL-4 or bFGF, whereas both TNF-alpha and IL-4 increased eotaxin release (p < 0.05). Both bFGF-induced fibroblast proliferation and TNF-alpha-induced ICAM-1 expression were significantly reduced by fluticasone, starting at the dose of 1 and 10 nM, respectively (p < 0.05). Fluticasone at concentrations of 1-100 nM effectively inhibited eotaxin release by TNF-alpha- or IL-4-stimulated fibroblasts (p < 0.05). CONCLUSIONS: The pharmacologic activity of fluticasone in patients with chronic upper airway inflammatory disease may include inhibition of resident fibroblast functions involved in airway inflammation and remodeling.

Administration, Topical↗
PubMed1996

Tachyphylaxis to histamine-induced wheal suppression by topical 0.05% clobetasol propionate in normal versus croton oil-induced dermatitic skin.

BACKGROUND: Patients often tell about reduced effectiveness of topical steroids on repeated use. Tachyphylaxis to these agents has been demonstrated in humans for vasoconstriction and histamine-induced wheal suppression in normal skin, but not in diseased skin. Relevance of these data to diseased skin is not clear. Further, the clinical impression does not appear to match tachyphylaxis shown in normal skin with regard to the time course. OBJECTIVES: To examine whether tachyphylaxis to histamine-induced wheal suppression by a topical steroid occurs in dermatitic skin and to determine its time course vis-à-vis normal skin. METHODS: Pharmacodynamic response to 0.05% clobetasol propionate applied daily under occlusion was measured by histamine-induced wheal suppression assay in 10 individuals. This test was performed on a steroid-treated normal site, on a steroid-treated site where dermatitis was induced by occlusive application of 40% croton oil, and on a vehicle-treated site in each individual at different intervals up to 14 days. RESULTS: Suppression of wheal volume started from second day in steroid-treated sites. There was significant difference in the wheal volume in steroid treated normal vs. dermatitic sites from day 2 to day 10. Maximum wheal suppression occurred earlier in dermatitic skin (day 4 vs. day 6). After this, the volume of wheal started increasing and became equal to control (complete tolerance) on 12th day in dermatitic skin and on 14th day in normal skin. CONCLUSIONS: Time courses of tachyphylaxis to the action of 0.05% clobetasol propionate were significantly different in normal skin and dermatitic skin. Complete tolerance occurred earlier in dermatitic skin compared to normal skin.

Administration, Topical↗
PubMed1992

Steroid-induced dermal thinning: discontinuous application of clobetasol-17-propionate ointment.

The skin thinning effect of discontinuous topical clobetasol-17-propionate applications was tested in human volunteers. Application frequencies were daily (1/0), every third day (1/2), every fifth day (1/4), every seventh day (1/6) and every ninth day (1/8). Clobetasol-17-propionate was administered topically under occlusion for 1 h. The treatment period was 41 days. There were no differences of the skin thinning effect of daily and 1/2 administration. The skin thinning effect of 1/4, 1/6 and 1/8 was smaller but also significant compared to controls. The curves demonstrating skin thinning effects initially were dropping off and reached a plateau within about 2 weeks. After finishing application, skin thickness normalized within 2 weeks. Because of these findings, a treatment interval of 3 days is discussed as therapeutically efficient.

Administration, Topical↗