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J Boutagy

Publications and source records attributed to J Boutagy.

32 records · Page 2Linked to original sources
PubMed1983

pH testing paper for measurement of intragastric acidity: an assessment.

Regular evaluation of the pH of aspirated gastric juice is an important part of the routine prevention of the stress ulceration syndrome. This study has examined the use of commercially available pH paper for this purpose. Both clear buffer solutions and samples of gastric aspirate were used to assess the reliability of four products, Merck Universal pH Indicator strips (Art. 9535), Lyphan Universal pH Indicator paper, Whatman Wide Range pH paper and Macherey-Nagel Universal pH paper. The results show that the Merck strips and Lyphan paper are very reliable for measuring gastric aspirate pH and that intensive care nursing staff can make accurate observations when using these papers.

Gastric Acidity Determination↗
PubMed1982

Cardenolide analogues. 14. Synthesis and biological activity of glucosides of C17 beta-modified derivatives of digitoxigenin.

An improved method for the synthesis of cardiac glycosides was used to prepare 3 beta-glucosides of digitoxigenin derivatives in which the 17 beta side chain was CH=CHX (X = COOH, CONH2, COCH3, CN, or COOR). We compared the inotropic activity of the compounds with that of digitoxigenin glucoside using guinea pig left atria. All compounds were active except for the acid (7) and the amide (8). The inactivity of the amide, in spite of its favorable shape and high capacity for forming intermolecular hydrogen bonds, is incompatible with some previous structure-activity relationship theories. Of the active genins, glucosidation enhanced activity by a factor of about 2. All glucosides, including those with high potency, showed rapid onset and offset of action. The stepwise fall in potency that occurred when the ester group (CH=CHCOOR) was increased in bulk supported previous suggestions that the portion of the digitalis receptor that interacts with the C17 side chain lies within a cleft.

Animals↗
PubMed1981

Cardenolide analogues. 11. Improved method for the use of Fétizon's reagent in the synthesis of cardiac glycosides.

An improved procedure has been developed for preparing glycosides of cardenolide genins. The method uses specially prepared Fétizon's reagent as catalyst, combined, in most cases, with mercuric cyanide and mercuric bromide. In the presence of this catalyst, genins react readily, at room temperature, with per-acetylated 1-bromo-sugars to give the acetylated glycosides in high yield with little or no side reaction. The reaction proceeds almost to completion in 30 to 60 min. The free glycoside is obtained by mild deacetylation using triethylamine/methanol/water (20:20:1) at room temperature for 72 h. Proof of structure was obtained using chemical ionization mass spectrometry, NMR spectroscopy and comparison of physical constants with published data. The compounds were tested for inotropic activity using the isolated guinea pig atrium.

Animals↗
PubMed1979

Cardenolide analogues: 10--characterization of cardiac glycosides by chemical ionization mass spectrometry.

The potential of chemical ionization mass spectrometry for the characterization of naturally occurring and semi-synthetic cardiac glycosides has been investigated. Methane, isobutane and ammonia were used as reactant gases. With the exception of ouabain, the ammonia chemical ionization mass spectra of the cardiac glycosides examined in this work contained abundant [M + NH4]+ions and abundant fragment ions formed by cleavage of glycoside bonds. Ammonia chemical ionization mass spectrometry was found to provide a rapid and sensitive method for the characterization of the products of glycosidation reactions. In contrast, the methane and isobutane chemical ionization mass spectra of the cardiac glycosides, with the exception of ouabain, did not contain protonated molecular ions and did not contain abundant fragment ions above m/z 400.

Ammonia↗
PubMed1979

Pharmacokinetics of cytosine arabinoside in patients with acute myeloid leukaemia.

1 The pharmacokinetics of cytosine arabinoside were studied after a single i.v. bolus of 2 mg/kg ara-C in patients with newly diagnosed untreated AML, using a bioassay and GC-MS method to measure the plasma concentrations. 2 Most patients showed a bi- or tri-phasic decline in plasma concentrations with time. Plasma clearance was 3.9 to 18.1 l/min as measured by the GC-MS method, and terminal half-lives varied from 7--107 min. 3 There was poor correlation of the GC-MS assay with the bioassay, probably because the latter was interfered with by the release of endogenous nucleosides from blasts after after ara-C. 4 Plasma concentrations were measured by GC-MS during continuous infusions in 14 patients. Plasma clearances were much lower than after a bolus, 0.39 to 5.25 l/min. 5 There was no correlation of response (remission or fall in peripheral blast count) with exposure to ara-C calculated from infusion dose, clearance and duration of infusion. 6 This study shows that ara-C pharmacokinetics varies markedly from patient to patient and that there is a wide range in the plasma concentrations associated with therapeutic response.

Adolescent↗
PubMed1978

Determination of cytosine arabinoside in human plasma by gas chromatography with a nitrogen-sensitive detector and by gas chromatography--mass spectrometry.

A method for the determination of cytosine arabinoside in the plasma of leukemic patients being treated with this drug is described using either gas--liquid chromatography with a nitrogen-sensitive flame ionization detector or gas chromatography--mass spectrometry (GC-MS). To increase volatility, a double derivative of cytosine arabinoside was used, prepared by acetylation and subsequent methylation. Cytidine was used as internal standard for the GC procedure. GC--MS was performed with either cytidine as internal standard and detection by single-ion monitoring or by the use of [2H3] acetate-methyl derivative of cytosine arabinoside as internal standard and subsequent multiple-ion monitoring. Attempted extraction of cytosine arabinoside from plasma with various organic solvents was unsuccessful, but protein precipitation with ethanol or trichloroacetic acid followed by washing of the aqueous residue with organic solvents to remove as many of the interfering substances as possible gave satisfactory results. The minimum detectable quantity of pure cytosine arabinoside was similar for both techniques (approximately 500 pg). However, with GC using a nitrogen-sensitive detector, the lower limit of detection from plasma was found to be approximately 40--70 ng per ml plasma whilst GC--MS showed greater analytical selectivity with a detection limit in some cases as low as 1 ng per ml plasma.

Chromatography, Gas↗
PubMed1977

Cardenolide analogues. VI. The metabolism of the prodrug diacetylcymarol in the rat.

1. Diacetylcymarol is an acetylated glycoside which is better absorbed than the parent glycoside, cymarol. 2. Diacetyl[19-3H]cymarol was rapidly metabolized and excreted by the rat following intraperitoneal administration. 3. The drug was metabolized extensively to polar compounds with the principal pathway involving loss of the C-19 acetyl group and probable demethylation of the sugar. 4. The bulk of the radioactive material was excreted in the bile and there was little reabsorption. 5. The results show that acetylation was successful in converting the poorly absorbed glycoside, cymarol, into a derivative that was rapidly absorbed from the peritoneal cavity. 6. Following or during absorption, the biologically inactive diacetylcymarol was converted to polar derivatives with potential therapeutic activity. However, subsequent elimination was so rapid that little therapeutic benefit could be expected.

Animals↗