Blood Estriol Conjugation During Human Pregnancy<sup>*</sup>

Touchstone, Joseph C.; Greene, John W.; McElroy, Robert C.; Murawec, Taras

doi:10.1021/bi00904a006

Cited by 54 publications

(13 citation statements)

References 18 publications

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“…Results for concentrations of the ES forms agreed with the previous work (J. C. Touchstone, J. W. Greene, Jr., R. C. McElroy, and T. Murawec [1963], Biochemistry 2, 653). No estrogen was found in the red cells by the present method.…”

Section: Apparatus and Column Conditionssupporting

confidence: 90%

Free and Conjugated Estrogens in Blood Plasma during Human Pregnancy^*

Touchstone¹,

Murawec²

1965

Biochemistry

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The concentrations of the free, glucosiduronate, and sulfate forms of estrone (E,), estradiol17p (E2), and estriol (E3) in maternal and umbilical cord blood are reported. Phenolsulfatase and @-glucuronidase hydrolyses followed extraction of the free ether-extractible estrogen. There was more El and Ez in the conjugated forms in the maternal than in cord plasma. El sulfate (4.1 rg) was the major estrogen S everal studies describing estrogen levels in blood have been published recently (Diczfalusy and Magnusson, 1958;Roy and Mackay, 1962; Maner ef al., 1963 ;Aldercreutz, 1964). These reports have evaluated the total amounts of estrone, estradiol-l7P, and estriol rather than differentiating between free and conjugated steroids. Recent reports from this laboratory describe a comparison of the conjugation of estriol in umbilical cord and in the maternal peripheral blood plasma . A preliminary report described the conjugation of estrone and estradiol-l 7p in both cord and maternal blood .The present report gives details of methodology and results of quantitation of estrone, estradiol-17& and estriol in plasma in the free form and after liberation by hydrolysis with @-glucuronidase and phenolsulfatase (Mylase P) in a larger series. Conjugates of estrone and estradiol-17P were found in larger quantity in the maternal blood than in cord blood. No estrogens were found in the red cells. Apparatus and Column ConditionsThe gas chromatograph used in this work was (Glowall Corp. Model A-110) equipped with a Lovelock detector using radium foil. The column, a glass coil (183 cm x 4 mm), was packed with a combination of 10% QF-1 (fluorosilicone polymer, Dow Corning) and 5 % L-45 (methylsilicone polymer, Dow Corning) on Gas-Chrom Z, 80-100 mesh (Applied Science). The substrates were coated on the support in one application other than E8 sulfate (4.4 pg 100 ml) found in the maternal blood. Both free E, and El were found in higher concentrations that their glucosiduronates.Results for concentrations of the ES forms agreed with the previous work (J. C. Touchstone, J. W. Greene, Jr., R. C. McElroy, and T. Murawec [1963], Biochemistry 2, 653). No estrogen was found in the red cells by the present method. by dissolving them in methylene chloride (5-6 volumes x the weight of support) and evaporating the solvent with constant stirring after addition of the support. The packing was dried in a vacuum oven and packed in the glass coil under a vacuum. The columns were conditioned at 270" for 2 days with argon flow at an inlet pressure of 10 psi. Operating conditions were: column and detector temperature, 250 " ; flash temperature, 270"; inlet pressure, 30 psi; and voltage, 1000. Samples were dissolved in 25 p1 of t-butyl alcohol and 2 to 4-pl aliquots were injected.Preparation of Red Cells and Blood Plasma Extracts. Heparinized blood was collected from the antecubital vein of women in the third trimester of pregnancy. Blood was milked from the umbilical cord at the time of separation from the fetus and pooled. Pools of 100 ml or more were use...

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Section: Apparatus and Column Conditionssupporting

confidence: 90%

Free and Conjugated Estrogens in Blood Plasma during Human Pregnancy^*

Touchstone¹,

Murawec²

1965

Biochemistry

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“…The plasma oestriol values rose throughout pregnancy and the range of values obtained using this method are similar to those obtained by Aitken, Preedy, Eton & Short (1958), Touchstone et al (1963), Smith & Hagerman (1965) and Nachtigall et al (1966). The values obtained during labour are similar to those reported by Jewelewicz, Bassett & Levitz (1969) and Rado, Deans Crystle & Townsley (1970).…”

Section: Normal Pregnancy and Laboursupporting

confidence: 88%

“…techniques for measuring oestriol in biological fluids have been developed. Touchstone, Greene, McElroy & Murawec (1963) used g.l.c. without derivative formation, Biggs et al (1969) prepared the 16,17-diacetate of oestriol 3-methyl ether, whereas Luukkainen & Adlercreutz (1963) utilized the 16,17-di-trimethylsilyl ether of oestriol 3-methyl ether.…”

Section: Introductionmentioning

confidence: 99%

Determination of Plasma Oestriol in Normal Pregnancy and Labour Using Gas-Liquid Chromatography

Coyle¹,

Mills²

1971

Journal of Endocrinology

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A method is described for estimating oestriol in 2-10 ml samples of human pregnancy peripheral plasma. It incorporates acid hydrolysis, chemical purification, methylation, chromatography on alumina columns, formation of a derivative and quantitative determination by gas chromatography. A radioactive internal standard was added to correct for procedural losses. Plasma oestriol determinations in five normal patients throughout pregnancy and delivery are reported.

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“…We obtained E 3 (Ͼ99% purity), [2,3,[4][5][6][7][8][9][10][11][12][13] C 3 ]E 3 (99 atom % 13 C), diethyl ether anhydrous, and methanol anhydrous from Sigma-Aldrich; acetonitrile and sodium bicarbonate [both American Chemical Society (ACS) grade] from J.T. Baker; acetone and formic acid (both ACS grade) from EMD Chemicals; pyridine-3-sulfonyl chloride (97%) from Matrix Scientific; charcoal-stripped human serum from Bioresource Technology; and polypropylene tubes (1.5 mL) from Brinkmann Instruments.…”

Section: Reagents and Instrumentsmentioning

confidence: 99%

“…The lowest uE 3 concentration in serum sample that could be quantitatively measured with a CV of 20% was defined as a limit of quantification (LOQ) of 0.2 ng/mL. The liquid-liquid extraction recovery was approximately 45% as assessed by quadruplicate measurements of samples spiked with [2,3,[4][5][6][7][8][9][10][11][12][13] C 3 ]E 3 . These results showed an increase in the analytical sensitivity of nearly a thousand-fold compared with that for underivatized E 3 on the same instrument (data not shown).…”

Section: Analytical Sensitivitymentioning

confidence: 99%

Measurement of Unconjugated Estriol in Serum by Liquid Chromatography–Tandem Mass Spectrometry and Assessment of the Accuracy of Chemiluminescent Immunoassays

et al. 2014

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BACKGROUND Unconjugated estriol (uE3) is routinely analyzed in clinical laboratories as risk assessment for Down syndrome. Immunoassays of various types are the most commonly used methods. The accuracies of RIAs and ELISAs for uE3 have been questioned, and to date there have been no independent studies investigating the accuracy of the relatively new chemiluminescent immunoassays. We developed and validated a liquid chromatography–tandem mass spectrometry (LC-MS/MS) method for uE3 measurements in serum. METHODS Serum samples from patients in the second trimester of pregnancy were used, and uE3 concentrations were measured by LC-MS/MS and the Beckman Coulter Access® 2 and Siemens IMMULITE 2000 automatic chemiluminescent immunoassay analyzers. RESULTS The LC-MS/MS method was validated and showed limit of detection 0.05 ng/mL; limit of quantification 0.2 ng/mL; linearity of response to 32 ng/mL; total imprecision of 16.2%, 10.4%, and 8.2% for uE3 at 1.10, 4.18, and 8.32 ng/mL, respectively; and analytical recoveries of 95.9%–104.2%. ANOVA of the correlation for LC-MS/MS results vs chemiluminescent immunoassays results showed R2 = 0.9678 (Access 2 = 0.9305 LC-MS/MS + 0.2177, Sy|x = 0.1786, P < 0.0001), and R2 = 0.9663 (IMMULITE 2000 = 0.8849 LC-MS/MS − 0.0403, Sy|x = 0.1738, P < 0.0001). Bland–Altman plots of uE3 results revealed concentration-dependent immunoassay biases. Mock risk analysis for Down syndrome showed no apparent difference in the risk assessment outcomes if the adjusted method-specific multiples of the median were used, and the assay imprecision was <10% CV. CONCLUSIONS Standardization of immunoassay methods for uE3 analysis is needed to improve the accuracy of the measurements.

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Blood Estriol Conjugation During Human Pregnancy^*

Cited by 54 publications

References 18 publications

Free and Conjugated Estrogens in Blood Plasma during Human Pregnancy^*

Free and Conjugated Estrogens in Blood Plasma during Human Pregnancy^*

Determination of Plasma Oestriol in Normal Pregnancy and Labour Using Gas-Liquid Chromatography

Measurement of Unconjugated Estriol in Serum by Liquid Chromatography–Tandem Mass Spectrometry and Assessment of the Accuracy of Chemiluminescent Immunoassays

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Blood Estriol Conjugation During Human Pregnancy*

Cited by 54 publications

References 18 publications

Free and Conjugated Estrogens in Blood Plasma during Human Pregnancy*

Free and Conjugated Estrogens in Blood Plasma during Human Pregnancy*

Determination of Plasma Oestriol in Normal Pregnancy and Labour Using Gas-Liquid Chromatography

Measurement of Unconjugated Estriol in Serum by Liquid Chromatography–Tandem Mass Spectrometry and Assessment of the Accuracy of Chemiluminescent Immunoassays

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Blood Estriol Conjugation During Human Pregnancy^*

Free and Conjugated Estrogens in Blood Plasma during Human Pregnancy^*

Free and Conjugated Estrogens in Blood Plasma during Human Pregnancy^*