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M Axelson

Publications and source records attributed to M Axelson.

At least 73 records · Page 4Linked to original sources
PubMed1982

Capillary gas chromatographic method for the analysis of lignans in human urine.

We describe a capillary column gas chromatographic (GC) method for the analysis of lignans in urine. Lignans are excreted as mono-glucuronides which are first extracted on a small reversed-phase cartridge of octadecylsilane bonded silica (Sep-Pak C18) and thereafter isolated by anion exchange chromatography on DEAE-Sephadex A-25, prepared in the acetate form. Lignan mono-glucuronides are enzymatically hydrolysed and re-extracted on a Sep-Pak C18 cartridge. Quantification is carried out by capillary column GC of the trimethylsilyl ether derivatives. The specificity of the method was checked by GC/MS and the intra-assay coefficient of variation (CV) for the two lignans, enterolactone (trans-2,3-bis(3-hydroxybenzyl)butyrolactone) and enterodiol (2.3-bis(3-hydroxybenzyl)butane-1,4-diol) varied between 5 and 8%. Some values for the excretion of these lignans by normal men and women are presented.

4-Butyrolactone↗
PubMed1981

Analysis of isomeric ethynylestradiol glucuronides in urine.

A method for separation and analysis of conjugates of ethynylestradiol in urine is described. Steroid conjugates are separated on a lipophilic strong anion exchanger (triethylaminohydroxypropyl Sephadex LH-230), and phenolic steroids released by enzyme hydrolysis or solvolysis ar isolated by chromatography on the same ion exchanger. Steroids carrying an ethynyl group are isolated by chromatography on SP-Sephadex (Ag+). Ethynylestradiol is analyzed by gas chromatography-mass spectrometry of the trimethylsilyl ether, using [9,11,11,12,12-(2)H5] ethynylestradiol and internal standard.

Ethinyl Estradiol↗
PubMed1981

The definitive identification of the lignans trans-2,3-bis(3-hydroxybenzyl)-gamma-butyrolactone and 2,3-bis(3-hydroxybenzyl)butane-1,4-diol in human and animal urine.

The definitive identification of the first lignans to be found in humans and animals is described. Gas chromatography--mass spectrometry, n.m.r. spectroscopy, i.r. spectroscopy and chemical techniques were employed to establish the structures of two lignans as trans-2,3-bis(3-hydroxybenzyl)-gamma-butyrolactone and 2,3-bis(3-hydroxybenzyl)butane-1,4-diol. Both compounds are essetially racemic. Evidence was also found for several methoxy analogues of these lignans in the vervet monkey.

4-Butyrolactone↗
PubMed1981

[Free and sulfo-conjugated dehydroepiandrosterone in the brain of mice with myelin biosynthesis disorders].

Dehydroepiandrosterone, either unconjugated (D) or conjugated to sulfuric acid (DS), has been identified in the brain of male Mice; DS had been previously found in Rat brain. DS amounts in posterior brain, were 0.8-2.0 ng/g in controls, and very much lower in dysmyelinic jimpy and quaking Mice of the same age. Conversely, amounts of D were increased in affected Mice, suggesting an impaired sulfoconjugation. Results may be explained by accumulation of D and DS in brain, unrelated to the endocrine system.

Animals↗
PubMed1981

Characterization and measurement of dehydroepiandrosterone sulfate in rat brain.

Dehydroepiandrosterone (3 beta-hydroxy-5-androsten-17-one, I) sulfate (Ia) has been characterized in the anterior and the posterior parts of the brain of adult male rats. Its level (1.58 +/- 0.14 and 4.89 +/- 1.06 ng/g, mean +/- SD, in anterior and posterior brain, respectively) largely exceeded that of I in brain (0.42 +/- 0.10 and 0.12 +/- 0.03 ng/g in anterior and posterior brain, respectively) and of Ia in plasma (0.26 +/- 0.13 ng/ml). Brain Ia level did not seem to depend on adrenal secretion; it was unchanged after administration of corticotropin or dexamethasone for 3 days, and no meaningful change occurred in brain 15 days after adrenalectomy plus orchiectomy, compared with sham-operated controls. In contrast, stress conditions prevailing 2 days after adrenalectomy plus orchiectomy or after the corresponding sham operation resulted in a significantly increased concentration of Ia in the brain. Changes of Ia level in brain occurred irrespective of changes in corresponding plasma samples. It is proposed that Ia formation or accumulation (or both) in the rat brain depends on in situ mechanisms unrelated to the peripheral endocrine gland system.

Adrenalectomy↗
PubMed1980

Lignans in man and in animal species.

In our laboratories, for several years, two phenolic compounds have been detected during gas chromatographic-mass spectrometric analysis of urinary steroid extracts from human and animal species. Although features of the mass spectra of their trimethylsilyl (TMS) ether derivatives resembled those of oestrogens, they were atypical of steroids. The possibility that they were artefacts of the isolation procedures was discounted after careful studies with blanks, by varying the extraction method and because they were present almost exclusively as conjugates of glucuronic acid. Several of the general characteristics of the unknown compounds were reported after one (referred to as compound 180/442) was found to have a cyclic pattern of excretion during the menstrual cycle of an adult vervet monkey (Fig. 1). An investigation of the nature and distribution of the compounds has shown them to be urinary constituents in humans, baboons, vervet monkeys and rats, and further related compounds have been detected, so far only in vervet monkey urine. We now report spectroscopic and chemical studies that show the two original compounds to be lignans, which have a 2,3-dibenzylbutane skeleton as their basic structure. Unlike all previously known natural lignans, invariably of plant origin, the two mammalian compounds carry phenolic hydroxy groups only in the meta position of the aromatic rings.

Adult↗