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Query: UMLS:C0338671 (Steroids)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A method for purifying the estrogen content of pregnancy urine with little loss of the labile estrogens is described. 50-fold purification is effected by precipitation with ammonium sulfate, and urinary corticosteroids and 50-60% of urinary ketosteroids are simultaneously eliminated. Antioxidant ascorbic acid is used as the additive in most stages of the procedure. Polar estrogens are leached in an organic-solvent-water partition system from neutal steroids, the remainder of which are removed by ion-exchange chromatography. Estrogens are read by mass spectrometry. Gas-liquid chromatography, using 2 chromatograms, revealed 12 estrogen peaks in normal pregnancy urine.
Steroids 1978 Sep
PMID:The preparation of pregnancy urine for an estrogen profile. 3 Oct 17

Sensitive methods for quantifying androgens were lacking. Therefore, a relatively simple procedure for separating steroids was combined with highly specific assay methods so that eight androgens could be measured with high accuracy, precision and sensitivity. Semi-automated separations on Sephadex LH-20 columns used heptane:methylene chloride:ethanol:water (50:50:1:0.12) and a flow rate of 17.0 min/ml. The six peaks eluted contained androstenedine; androsterone, epiandrosterone and dihydrotestosterone; testosterone and dehydroepiandrosterone; 3alpha-androstanediol; 3beta-androstanediol; and androstenediol. Androstenedione, dehydroepiandrosterone and androstenediol were quantified using specific antisera (sensitivity less than or equal to 75 pg). Testosterone and dihydrotestosterone were measured by competitive protein-binding assays using rabbit TeBG (sensitivity less than or equal to 150 pg). 3alpha- and 3beta-androstanediol were similarly assayed using human TeBG (sensitivity approximately 150 pg). Androsterone was reduced with NaBH4 and the resulting 3alpha-androstanediol was assayed using human TeBG (sensitivity approximately 200 pg). Inter- and intra-assay variations were less than 10% for radioimmunoassays and less than 16% for competitive protein-binding assays over the entire dose response curve.
Steroids 1976 Nov
PMID:Simultaneous ultramicroanalysis of both 17-keto-and 17beta-hydroxy androgens in biological fluids. 13 14

Several radioactive estrogens possessing one, two and three hydroxyl groups were injected orally (and in the case of estrone sulfate also intraperitoneally) into adult male rats. The rats were either intact or had ligated or cannulated bile ducts. Two unconjugated estrogen tetrols together represented 21 - 87% of the total metabolites in the intact rat. One of the tetrols was 2-hydroxyestriol (estra-1,3,5(10)-triene-2,3,16alpha,17beta-tetrol); the other may be estra-1,3,5(10)-triene-2,3,6xi,17beta-tetrol but this was not confirmed. It is concluded that poly-hydroxylated estrogens represent a very large proportion of the previously unidentified water-soluble metabolites of the estrogens in the adult male rat.
Steroids 1976 Mar
PMID:Water-soluble metabolites of the estrogens. Quantitation of C-18 tetrols in rat feces. 17 75

Two unusual cases of the watery diarrhea syndrome are presented. In one patient an adrenal medullary tumor, a pheochromocytoma that produced vasoactive intestinal polypeptide (VIP) was excised with total relief of symptoms. The second patient a 65-year-old man with abrupt onset of massive watery diarrhea that led to acidosis and coma was symptomatically controlled for one year on 10 mg/day of prednisone. Elevated levels of VIP returned to normal after prednisone therapy was started. A benign islet cell tumor not localized by angiography was removed by distal pancreatic resection. Tissue levels of VIP were markedly elevated. VIP is a humoral mediator of the water diarrhea syndrome. Both benign and malignant pancreatic and extrapancreatic tumors may cause the watery diarrhea syndrome. Steroids may cause symptomatic relief of the diarrhea by lowering peptide levels to normal. The term watery diarrhea syndrome may be more accurate than the pancreatic cholera syndrome.
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PMID:Watery diarrhea syndrome. Two unusual cases and further evidence that VIP is a humoral mediator. 20 79

Irradiation of testosterone, 4-androstene-3,17-dione, or their "half-molecule" 4,4a,5,6,7,8-hexahydro-4a-methyl-2(3H)-naphthalenone in dilute aqueous solutions with ultraviolet light of 254 nm wavelength caused rapid addition of water across the olefinic bond with formation of 5,17 beta-dihydroxy-5 alpha-androstan-3-one, 5-hydroxy-5 alpha-androstane-3-17-dione, and 9-hydroxy-10-methyl-2-decalone, respectively. Time-lapse spectrometry in the ultraviolet region showed that the photohydration of the androgenic steroids was extremely efficient and virtually free of the side reactions. Preparative photolytic reactions carried out in water-methanol solutions allowed isolation and characterization of photoproducts.
Steroids 1979 May
PMID:Photohydration of testosterone and 4-androstene-3,17-dione in aqueous solution. 46 94

The mass spectral elimination of water in epimeric 1,3-diols of vitamin D3 (colecalciferol) series has been investigated. It was found that the mass spectra of these steroisomers differ sharply in the relative intensities of the ions M-H2O (m/e 382) and a-H2O (m/e +/- 34), where ion a (formed via formal cleavage of the 7, 8-double bond) is characteristic of vitamin D3 and its derivatives. So while epimeric 1, 3-diols of vitamin D3 series have very close UV and NMR characteristics, the comparison of the ratios of the peaks M-H2O and M.+, a-H2O and a, respectively, makes it possible to distinguish between stereoisomeric 1 alpha, 3 beta-, 1 beta, 3 beta-, 1 alpha, 3 alpha- and 1 beta, 3 alpha-diols using their mass spectra.
Steroids 1979 May
PMID:Determination of the configuration of epimeric diols of vitamin D3 series by mass spectrometry. 46

Bile acid derivatives, with and without C-3 sulfate groups, and having either the diazo- or halomethylketone moieties, have been synthesized in good yield and purity. The synthetic sequence, COOH leads to COC1 leads to COCHN2 leads to COCH2X, was used with deoxycholic and cholic acids, which requires carefully controlled quench, work-up, and purification procedures, especially for the 3-sulfate esters (made from deoxycholic acid derivatives only). The pure title compounds are anticipated to be useful chemical probes (affinity labels), especially the completely water soluble sulfates, toward our studies of ileal active transport of bile salts. A new use for Sephadex LH-20 as a sulfate ester protecting group is reported. Also developed were the use of acetamide hydrochloride complex as a mild hydrochlorination reagent and a neutral desalting method for sulfate esters of deoxycholic acid derivatives.
Steroids 1979 Aug
PMID:The synthesis of diazo, halo, and sulfoxy bile acid derivatives: potential affinity labels. 49 60

The interaction between cholesterol and band 3-protein from human erythrocyte membranes was studied by incorporating the solubilized protein into monolayers of cholesterol and related sterols at the air-water interface and measuring the changes in surface pressure which accompanied protein incorporation. The following results were obtained: 1) Band 3-protein shows a very strong interaction with cholesterol monolayers. Both apolar and polar bonds contribute to this interaction. 2) Steroids with a structure slightly different from that of cholesterol (especially with respect to the polar group and the side chain) in most cases show a reduced affinity for band 3-protein. Thus, the protein-sterol interaction is highly specific. It is assumed that the protein-cholesterol interaction can be subidivided into two parts: an unspecific one which results from contributions from several sterol molecules, and a specific one which is due to the high affinity binding of the protein and cholesterol. The structural element responsible for the high affinity interaction is assumed to be a sterol-binding niche on the surface of band 3-protein. The sterol is thought to be held in the niche by a hydrogen bond at its polar head and a variety of hydrophobic bonds along its ring system and side chain.
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PMID:Interactions of band 3-protein from human erythrocyte membranes with cholesterol and cholesterol analogues. 51 Nov 12

It was reported in a previous study that serum estradiol-17beta (E2) was elevated in rats after retrochiasmatic transection (FC). Serum E2 was also higher in estradiol cypionate treated, ovariectomized (OVX) rats that had been subjected to FC than in those that had not. This suggested that increased secretion of E2 was not the only factor responsible for elevated serum E2 after FC. To ascertain the contribution of decreased metabolism of E2 to this response, liver tissue slices were incubated with 3H-estradiol-17beta, and the rates of 3H uptake and conversion to water-soluble conjugates were measured. The rate of uptake of 3H by the tissue was not indicative of the rate of conjugate formation. Livers of rats with high serum E2 exhibited lower rates of 3H uptake than those of rats with low serum E2. Even so, the formation of 3H conjugates was greater in liver of rats with high serum E2. As hypothesized, livers of rats with FC formed conjugates at a significantly lower rate than those of similarly treated rats without FC. Thus, FC of an intact rat leads to an increase in serum E2 by increasing the secretion of E2, and apparently also by decreasing the rate of E2 metabolism by the liver.
Steroids 1978 Jan
PMID:In vitro liver clearance of tritiated estradiol-17beta in the female rat after retrochiasmatic transection and ovariectomy. 56 77

Of the polar lipids studied (phospholipids and glycolipids), only phosphatidylcholine and sphingomyelin can disperse in water with up to 2 mol cholesterol/mol polar lipid. However, mixtures of phosphatidylethanolamine with small amounts of phosphatidylcholine and mixed lipids from mitochondria and myelin will also form sterol-rich dispersions. Steroids in which the 3beta-OH group is replaced by an oxo function do not form such steroid-rich dispersions. Electron microscopy and optical rotatory dispersion (ORD) show that sterols disperse with cerebrosides and gangliosides to form cylindrical structures with the regions around C atoms 3 and 7 of the sterol in less polar environments than those they occupy in phospholipid liposomes. It is proposed that choline-containing phospholipids facilitate entry of sterol molecules into the outer leaflet of cell surface membranes but that the phospholipid composition itself will not give rise to an asymmetric distribution of sterol in membranes with a high cholesterol content.
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PMID:The dispersion of cholesterol with phospholipids and glycolipids. 59 71


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