Biomedical subjects

M G Metcalf

Publications and source records attributed to M G Metcalf.

At least 55 records · Page 3Linked to original sources

PubMed1978

Assessment of ovarian function in perimenopausal women after stopping oral contraceptives.

Ovarian function was assessed by measuring plasma gonadotrophins, urinary oestrogen and urinary pregnanediol levels, every week for four weeks, in 34 women, aged 45 to 57 years, after withdrawal of oral contraceptive therapy. A rise in urinary pregnanediol excretion occurred in 14 patients suggesting that ovulation had occurred and that these patients were "premenopausal". Elevated serum gonadotrophin values and persistently low urinary oestrogen and pregnanediol excretion occurred in 13 patients suggesting ovarian failure or a "postmenopausal" state. However, one apparently "postmenopausal" patient later showed hormonal evidence of ovulation, indicating fluctuation in ovarian function. There were 7 patients with "indeterminate" hormone profiles whose ovarian function was difficult to assess. All patients excreting more than 45 nmol of oestrogen a day had a spontaneous period within 45 days of stopping hormone therapy.

Adult↗

PubMed1977

Analysis of pregnanediol in urine: trental interference.

Patients given Trental (pentoxifyllin, Hoechst A.G.) for the treatment of vascular disorders excrete a substance which interferes with the gas chromatographic anlaysis of pregnanediol. The interfering substance appeared in urine within 4-5 h of the ingestion of 100 mg Trental, and was cleared during the next 4-10 h. The administration of 300 mg/24 h to an anovulatory woman caused an apparent increase in her output of pregnanediol of from less than 1 to 65.8 micronmol/24 h.

Chromatography, Gas↗

PubMed1977

Analysis of estrogens in small samples of non-pregnancy urine.

1. In a widely used procedure for measuring estrogens in non-pregnancy urine(1), 0.01 to 0.05% of a 24hr specimen is taken for analysis. 2. There is an inverse relationship between 24hr urine volume (chi) and creatinine concentration (81 observations on 75 women; r = -0.780; creatinine (g/iota) = 2.34 -0987 chi(iota); P less than 0.001). 3. The data suggest that, when 24hr output is unknown, creatinine levels may be used to select the amount of urine for estrogen analysis. 4. Volumes found to contain 0.01 - 0.05% of a 24hr specimen were: -- (formula: see text).

Adolescent↗

PubMed1976

Are 24-hour urine collections necessary for the measurement of steroid excretion rates?

In the assessment of ovarian activity, testicular response in human chorionic gonadotrophin (HCG), and placental and fetal viability during pregnancy, measurements made on small samples of urine may be used to monitor changes in 24h steroid output; the collection of 24h urine specimens is not necessary. For women, 24h output approximately 10 R (R, steroid/creatinine in small urine samples; concentrations expressed in SI units of amount). For men, 24h output approximately 14 R.

17-Ketosteroids↗

PubMed1976

Use of small samples of urine to monitor testicular response to human chorionic gonadotropin.

The increased urinary excretion of androsterone and aetiocholanolone, 17-oxosteroids, and oestrogens which occurs after the administration of human chorionic gonadotropin to normal men, was followed by measuring steroid to creatinine ratios in small samples of urine. For androsterone + aetiocholanolone, values of the ratio correspond closely with 24 h output (correlation coefficients: 0.91, 0.92, and 0.91 for first morning, mid-morning, and mid-afternoon urine specimens.) Comparable correlation coefficients for the 17-oxosteroids in urine were 0.90, 0.95, and 0.91; and for oestrogens, 0.88, 0.87, and 0.86.

17-Ketosteroids↗

PubMed1976

Dehydroepiandrosterone sulfate in plasma: hydrolysis, extraction and radioimmunoassay.

At pH 4.5, the hydrolysis of 3beta-hydroxy-5-androsten-17-one 3-sulfate (DHA-SO4) to DHA was complete within 75 min at 120 degrees or 4h at 100 degrees. In the same conditions, the 3alpha-SO4 of androsterone was stable, and only 8.5% of the 3beta-SO4 of epiandrosterone hydrolysed to epiandrosterone. Of the sulfates of 5-androstene-3beta, 17beta-diol, 100% of the 3beta-mono-SO4, 2% OF THE 17BETA-MONO-SO4 and none of the 3beta, 17beta-di-SO4 was converted to 5-androstenediol. Denatured plasma proteins adsorbed DHA. The recovery of DHA from plasma diluted 1:100, 58.7 +/- 6.2% (mean +/- S.D.). In similar conditions the recovery of cholesterol from plasma diluted 1:20, was 0.12 - 1.76% (mean, 0.44%). A radioimmunoassay for DHA in extracts of hydrolysed plasma is described. Results for normal subjects in the age range 17-45y were 192 +/- 73mug/dl (22 men) and 158 +/- 57mug/dl (40 women).

Adult↗

PubMed1976

Calculation of estrogen excretion rates from urinary estrogen to creatinine ratios.

1. The excretion of estrogens by 42 menstruant and 7 pregnant (1st trimester) women ranged from 2 - 550 mug/24hr. 2. These changes were followed by measuring estrogen to creatinine ratios in small samples of urine. 3. Values of the ratio changed little in each 24 hr, and correlated closely with daily estrogen output (r = 0.971; P less than 0.001; estrogens (mug/24hr) =(see article. 4. The data suggests that ovarian activity in women, including those given gonadotropins to induce ovulation, may be followed by measuring estrogen to creatinine ratios in small samples of urine; the collection of 24 hr samples is unnecessary.

Circadian Rhythm↗

PubMed1976

Response of plasma testosterone, urinary 17-oxosteroids, oestrogens, and androsterone plus aetiocholanolone to human chorionic gonadotrophin in dexamethasone-suppressed men.

The administration of human chorionic gonadotrophin (HCG) to dexamethasone-suppressed men caused parallel changes in the concentration of plasma testosterone and in the urinary output of androsterone+aetiocholanolone, total 17-oxosteroids and oestrogens. Discrepant results occurred in only four of the thirty-seven men tested. With these exceptions, the response to HCG could by followed as well by measuring androsterone+aetiocholanolone, 17-oxosteroid or oestrogen excretion rates as by following plasma testosterone levels. The most sensitive index of response was the rate of appearance of oestrogens in urine, and the next that of androsterone+aetiocholanolone.

17-Ketosteroids↗

PubMed1974