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J Fiet

Publications and source records attributed to J Fiet.

At least 91 records · Page 5Linked to original sources
PubMed1990

Circadian variations in plasma levels of hypophyseal, adrenocortical and testicular hormones in men infected with human immunodeficiency virus.

Alterations in the circadian time structure of the secretion of several hormones were investigated in 13 male patients infected with human immunodeficiency virus (HIV). Seven were asymptomatic (classified CDC II, according to the criteria of the Atlanta Centers for Disease Control), and 6 had acquired immunodeficiency syndrome (CDC IV). Ten healthy males volunteered as controls. Plasma levels of dehydroepiandrosterone (DHEA) and its sulfate (DHEA-S), cortisol, testosterone, ACTH, and beta-endorphin were determined by RIA in blood samples obtained every 4 h from 0830-0830 h the next morning. Data were analyzed both by two-way analysis of variance and the cosinor method. Circadian rhythms were statistically validated for each of the six hormones in each of the three groups of subjects. Compared with the control subjects, mesors (24-h adjusted means) were significantly higher for cortisol and lower for DHEA, DHEA-S, and ACTH (P less than 0.001 for all four hormones) in all HIV-infected patients. Plasma testosterone mesors were similar in controls and CDC II patients, but decreased significantly in the CDC IV patient group (P less than 0.05). Analysis of the circadian rhythms of plasma hormone levels clearly indicated an altered adrenal hormonal state in HIV-infected male patients, even during the asymptomatic period of the infection. For instance, plasma cortisol at 0430 h was more than twice as high in HIV-infected patients as it was in time-qualified controls. Although patients already had elevated plasma cortisol and lowered adrenal androgen levels at this stage, hypogonadism was not observed, as gauged by plasma testosterone concentrations. We speculate that the primary hormonal defect in HIV-infected patients is increased cortisol secretion resulting from circadian-varying stimulation of the adrenal cortex by a factor other than pituitary ACTH. This factor might be a stimulating substance secreted primarily by infected immune cells. Excess cortisol would lower adrenal androgen secretion by shifting adrenal steroid biosynthesis toward glucocorticoids and decreasing pituitary ACTH secretion via a negative feedback mechanism.

Acquired Immunodeficiency Syndrome↗
PubMed1989

[21-deoxycortisol. A new marker of virilizing adrenal hyperplasia caused by 21-hydroxylase deficiency].

21-deoxycortisol is a steroid produced mainly by the adrenal gland. Its normal plasma baseline concentrations (0.03 to 0.30 n/ml) and its concentrations after tetracosactide injection (0.15 to 0.76 ng/ml) do not significantly vary with age, sex and phases of the menstrual cycle. 21-deoxycortisol was assayed in plasma by a specific radioimmunological method and its values were compared with those of 17-OH progesterone in heterozygous subjects with the classical and non-classical forms of 21-hydroxylase deficiency, and in the amniotic fluid of foetuses with this deficiency. Baseline concentrations of 21-deoxycortisol in the classical forms of 21-hydroxylase deficiency (n = 12; 55.36 to 186.6 ng/ml) and post-tetracosactide concentrations in non-classical late onset forms (n = 31; 4.04 to 47 ng/ml) were much higher than in normal subjects, thus making this steroid as sensitive as, or even more sensitive than 17-OH progesterone in diagnosing 21-hydroxylase deficiency. Post-tetracosactide assays of 21-deoxycortisol in 84 heterozygous subjects with 21-hydroxylase deficiency (0.70 to 5.40 ng/ml) enabled these subjects to be detected with a more than 90 percent sensitivity, which cannot be obtained with 17-OH progesterone assays. 21-deoxycortisol concentrations in the amniotic fluid of foetuses with 21-hydroxylase deficiency (n = 11; 0.391 to 0.930 ng/ml) were constantly superior to those observed in normal foetuses (n = 38; 0.034 to 0.221 ng/ml), so that the deficiency can be diagnosed with the steroid as easily as with 17-OH progesterone.

17-Hydroxycorticosteroids↗
PubMed1989

Prevention of the transient adverse effects of a gonadotropin-releasing hormone analogue (buserelin) in metastatic prostatic carcinoma by administration of an antiandrogen (nilutamide).

Gonadotropin-releasing hormone (GnRH) analogues administered for the treatment of advanced prostatic cancer induce a transient increase in plasma testosterone levels during the first week of treatment, often with a secondary rise in plasma levels of prostatic acid phosphatase and a flareup of disease. To determine whether the antiandrogen nilutamide (Anandron) blocks these effects, we carried out a multicenter, placebo-controlled study of nilutamide in men with prostatic cancer treated with the GnRH analogue buserelin. Thirty-six men with disseminated prostatic cancer and elevated plasma levels of prostatic acid phosphatase were randomly assigned to two groups. Group 1 included 17 men who received buserelin (500 micrograms daily subcutaneously) and nilutamide (300 mg daily by mouth); group 2 included 19 men treated with buserelin and placebo. Symptoms were assessed, and plasma was collected before treatment, daily for 14 days, and on days 18, 22, and 29 after the initiation of treatment. Bone pain appeared or worsened in 5 of the 17 men in group 1 and in 12 of the 19 men in group 2 (P less than 0.05). Acute urinary obstruction occurred in one man in group 2. Despite similar changes in the plasma testosterone levels in both groups, the median concentration of plasma prostatic acid phosphatase decreased almost immediately in group 1, but increased transiently, then decreased on day 14 in group 2. Median levels of prostate-specific antigen decreased immediately in group 1 and decreased on day 8 in group 2. We conclude that nilutamide can prevent the adverse consequences of the buserelin-induced transient rise in plasma testosterone levels in men with advanced prostate cancer treated with a GnRH analogue.

Acid Phosphatase↗
PubMed1989

Increased plasma 21-deoxycorticosterone (21-DB) levels in late-onset adrenal 21-hydroxylase deficiency suggest a mild defect of the mineralocorticoid pathway.

Plasma 21-deoxycorticosterone (21-DB) concentrations were measured before (basal) and 1 h after ACTH stimulation in a population of 34 normal subjects, 18 patients with the late-onset form of congenital adrenal hyperplasia (LO-CAH) due to 21-hydroxylase deficiency, and 19 LOCAH heterozygotes. For comparison, plasma 21-deoxycortisol (21-DOF) and 17-hydroxyprogesterone (17-OHP) were determined simultaneously in the same subjects. Plasma 21-DB concentrations as well as those of 21-DOF did not vary significantly as a function of age, sex, or phase of the menstrual cycle, in contrast to plasma 17-OHP. The mean plasma 21-DB concentrations in normal subjects (adult men, follicular and luteal phase women, and children) were 19.0 +/- 9.5 (+/- SD) pmol/L before and 73.2 +/- 31.0 after ACTH stimulation. In the LOCAH patient group, the mean post-ACTH plasma 21-DB concentration was 1736.0 +/- 1243.0 pmol/L, and all values were above the highest post-ACTH value (148.2 pmol/L) in the normal subjects. Similarly, in the LOCAH patients the post-ACTH plasma 21-DOF concentration was 33.7 +/- 20.3 nmol/L, and the post-ACTH plasma 17-OHP value was 134.0 +/- 70.6 nmol/L; all LOCAH patients had supranormal responses to ACTH. However, 38.9%, 11.2% and 16.7% of the basal plasma 21-DB, 21-DOF, and 17-OHP values in the LOCAH patients overlapped those in the normal subjects. There was a rather large overlap (63.2%) in post-ACTH plasma 21-DB levels between the LOCAH heterozygotes and the normal subjects; it was less than the overlap in plasma 17-OHP (74%) and more than the overlap in plasma 21-DOF values (5.2%) in these same 2 groups. There was moderate overlap (21%) in the post-ACTH plasma 21-DB levels between the LOCAH heterozygotes and LOCAH patients, but no overlap between these 2 groups for either 21-DOF or 17-OHP. The abnormally elevated post-ACTH plasma 21-DB levels found in all the LOCAH patients as well as in some LOCAH heterozygotes suggest the existence of minor 21-hydroxylase deficiency in the mineralocorticoid synthetic pathway in these patients in addition to the well known impairment in the glucocorticoid pathway demonstrated by the elevated post-ACTH 21-DOF and 17-OHP levels.

17-alpha-Hydroxyprogesterone↗
PubMed1989

[Early disturbance of the circadian rhythm of T and B lymphocytes in human immunodeficiency virus infection].

Circadian rhythms in circulating B and T (CD3, CD4, CD8) lymphocyte subsets and in plasma cortisol were studied in 13 HIV-infected men and 14 healthy male controls. The circadian maximum (acrophase) of plasma cortisol was similar in both groups, approximately 8.00 A.M., however, a statistically significant increase was found in the 24 hour-mean value (mesor) of infected patients as compared to healthy controls. Circadian rhythms were statistically validated in all lymphocyte subsets of healthy controls, whereas, large alterations were found in patients with acquired immunodeficiency syndrome (AIDS), already in asymptomatic infected individuals. The alterations concern the mesor and the amplitude for B and CD4 lymphocytes and all cycle parameters for CD3 and CD8 lymphocytes.

Acquired Immunodeficiency Syndrome↗
PubMed1989

[Effect of estroprogestative drugs on the secretion of corticoadrenal hormones].

Estro-progestative drugs (EPD) have been used for many years and multiple secondary effects have been reported concerning mainly the glucidic and lipidic metabolisms. Effects of EPD on steroid metabolism have also been described and the authors present a review of the literature on this subject. Particularly it appears that EPD affect: the glucocorticoid metabolism, with augmentation of total cortisol although not in its free-form (augmentation of transcortine), the adrenal androgens metabolism, with diminution of their circulating rates, the aldosterone metabolism with augmentation of its secretion. These biological constatations could help explaining some clinical features occurring with administration of EPD: diminution of hirsutism and/or acne, augmentation of body weight, appearance of hypertension.

Adrenal Cortex Hormones↗
PubMed1988

Plasma adrenocorticotrophin and cortisol responses to acute hypoxia at rest and during exercise.

Plasma adrenocorticotrophin (ACTH) and cortisol (F) concentrations were studied in six male subjects under normoxic (N) and acute hypoxic (H) conditions (altitude 3000 m) in a hypobaric chamber. Comparisons were made at rest, at 15, 30, and 60 min of exercise (65% VO2max), and after a 10 min recovery period. Mean (+/- SE) resting plasma ACTH levels were significantly higher in H (18.6 +/- 5.7 pmol.l-1) than in N (9.6 +/- 1.6 pmol.l-1) but no difference in resting plasma cortisol was observed between the two conditions. Both plasma ACTH and F concentrations were significantly increased at 60 min of exercise and during the recovery period under normoxic conditions. Hypoxia did not affect the ACTH response to exercise but reduced cortisol elevation. The changes in plasma cortisol concentration from rest to exercise were significantly correlated to ACTH under normoxic (r = 0.89, p less than 0.001) but not under hypoxic (r = 0.43, NS) conditions. Plasma lactate concentration was higher at the end of exercise in hypoxia (p less than 0.01), and no correlation existed between plasma lactate and ACTH levels. These observations provide further evidence that at sea level the increase in plasma cortisol levels during exercise is the result of ACTH-induced steroidogenesis. The responses observed at rest and during exercise in hypoxia suggest that adrenal sensitivity for ACTH may be altered.

Adrenocorticotropic Hormone↗
PubMed1988

Dissociated response of aldosterone from plasma renin activity during prolonged exercise under hypoxia.

6 healthy male subjects on a fixed salt-diet performed 1 hour ergocycle exercise at 65% of VO2 max in normoxic (N) and hypoxic (H) conditions. Blood samples were taken at intervals for estimations of plasma aldosterone (PAC), angiotensin converting enzyme (ACE), adrenocorticotrophic hormone (ACTH) and catecholamine concentrations. Plasma volume reductions with exercise were similar in N (4.3 +/- 1%) and H (4.0 +/- 1%). PRA response to exercise was increased by hypoxia while PAC and plasma catecholamine rose to a similar extent in both conditions. Increases in ACTH concentration occurred at the end of exercise but no difference was found between high and low altitudes. Plasma ACE remained unchanged throughout exercise in either condition. These results indicate that hypoxemia interferes with PRA-mediated aldosterone secretion. The variations in plasma ACTH levels during exercise in hypoxia do not appear responsible for this interference.

Adult↗
PubMed1988

Metabolic effects of combined cyproterone acetate and percutaneous 17 beta oestradiol after six and twelve months therapy in 61 patients.

The metabolic effects of combined cyproterone acetate (50 mg) and percutaneous 17 beta oestradiol were studied during one year in 61 patients admitted for hyperandrogenia. Before treatment and at 6 and 12 months the following tests were performed: oral glucose tolerance test (OGTT) with insulinemia dosage, determination of total cholesterol, LDL, VLDL and HDL fractions, triglycerids, A1 and B apoproteins, liver function tests: bilirubinemia, alkaline phosphatases, transaminases and gamma glutamyl transferases. The patients' mean age was 27.0 +/- 6.8 years, the body mass index was 22.4 +/- 3.5 kg/m2. After one year of treatment the body mass index was not modified. Blood glucose slightly increased during OGTT; at 6 months this was significant at +30 minutes, at 12 months at +30, +60 and +90 minutes (P less than 0.05). There was no variation in insulinemia during OGTT. Total cholesterol decreased significantly at 6 and 12 months (P less than 0.001), this was associated with a decrease in HDL cholesterol, but without modification of the LDL + VLDL/HDL ratio. Decrease in HDL cholesterol was associated with a significant decrease in A1 apoproteins. No change in triglycerids and in liver function tests was observed at either date. In conclusion the metabolic effects of this association are described. These effects are minimal compared to those observed with cyproterone acetate and ethinyl oestradiol association in the literature. However, attention should be drawn to the possibility of glucose intolerance and decrease in HDL cholesterol and A1 apoproteins.

Adult↗
PubMed1988

Prenatal diagnosis of 21-hydroxylase deficiency congenital adrenal hyperplasia by simultaneous radioimmunoassay of 21-deoxycortisol and 17-hydroxyprogesterone in amniotic fluid.

Amniotic fluid levels of 21-deoxycortisol (21-DOF) and 17-hydroxyprogesterone (17-OHP) were measured in 49 pregnancies, including 31 pregnancies at risk for CAH. The results were compared with those obtained by HLA typing and linkage analysis to a HLA DNA probe. The mean amniotic fluid levels in the control pregnancies were 0.28 nmol/L for 21-DOF and 4.1 nmol/L for 17-OHP. The levels were similar in early and midpregnancy for 21-DOF (0.29 vs. 0.27 nmol/L) and 17-OHP (3.4 vs. 4.2 nmol/L). The amniotic fluid 21-DOF level was 1.75 nmol/L in affected pregnancies, significantly higher than in the control pregnancies (mean, 0.28 nmol/L). The mean amniotic fluid 17-OHP level in the affected pregnancies (30.5 nmol/L) also was significantly higher than that in the control pregnancies (4.10 nmol/L). Simultaneous measurement of 21-DOF and 17-OHP levels in amniotic fluid from 10-18 weeks of gestation can be used for early diagnosis of congenital adrenal hyperplasia.

17-Hydroxycorticosteroids↗
PubMed1988

Comparison of basal and adrenocorticotropin-stimulated plasma 21-deoxycortisol and 17-hydroxyprogesterone values as biological markers of late-onset adrenal hyperplasia.

Plasma 21-deoxycortisol (21-DOF) and 17-hydroxyprogesterone (17-OHP) concentrations were assayed before (basal) and 1 h after ACTH stimulation in 4 groups of normal subjects (35 follicular phase women, 22 luteal phase women, 33 adult men, and 15 prepubertal children) and in a group of 31 patients with the late-onset form of congenital adrenal hyperplasia (LOCAH) due to 21-hydroxylase deficiency as well as in 31 LOCAH) heterozygotes. The mean basal plasma 21-DOF concentrations in each of the 4 groups of normal subjects were between 8 ng/dL (0.23 nmol/L) and 11 ng/dL (0.31 nmol/L), and they increased significantly after ACTH stimulation to between 36 ng/dL (1.04 nmol/L) and 44 ng/dL (1.27 nmol/L). There were no differences in basal or ACTH-stimulated plasma 21-DOF levels in these 4 groups, whereas their basal and post-ACTH plasma 17-OHP levels did vary. Among the LOCAH patients, 83.8% had basal plasma 21-DOF levels and 61.2% had basal plasma 17-OHP levels higher than the highest basal 21-DOF [30 ng/dL (0.86 nmol/L)] and 17-OHP [450 ng/dL (13.61 nmol/L)] concentrations in the normal subjects, and all individual 21-DOF and 17-OHP levels after ACTH stimulation [greater than or equal to 404 ng/dL (11.67 nmol/L) and greater than or equal to 1040 ng/dL (31.47 nmol/L), respectively] were markedly higher than the highest 21-DOF [76 ng/dL (2.19 nmol/L)] and 17-OHP [580 ng/dL (17.55 nmol/L)] levels in the normal subjects. The mean post-ACTH/basal plasma level ratios among the LOCAH patients were 19.75 for 21-DOF and 8.03 for 17-OHP. In LOCAH heterozygotes, basal 21-DOF values were higher than normal in 48.3%, and post-ACTH values were higher than normal in 93.5% of the cases. In contrast, basal plasma 17-OHP levels were similar in LOCAH heterozygotes and normal subjects, and only 16.1% of the LOCAH heterozygotes had post-ACTH plasma 17-OHP levels higher than the highest normal value. If sex and phase of the menstrual cycle are taken into account, along with the incremental responses (post-ACTH minus baseline value) of plasma 21-DOF and 17-OHP, to compare LOCAH heterozygotes and normal subjects, the discriminating power for detection of heterozygocity was somewhat increased for 21-DOF (to 100%) and appreciably increased for 17-OHP (to 30%).(ABSTRACT TRUNCATED AT 400 WORDS)

17-Hydroxycorticosteroids↗
PubMed1988

Hypogonadism in AIDS.

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Acquired Immunodeficiency Syndrome↗
PubMed1987

The measurement of 11 beta-hydroxy-4-pregnene-3,20-dione (21-deoxycorticosterone) by radioimmunoassay in human plasma.

A specific radioimmunoassay (RIA) method is described for the determination of 21-deoxycorticosterone (21 DB) in human plasma. 21-Deoxycorticosterone-3-(O-carboxymethyl) oxime-bovine serum albumin conjugate was used to generate antisera in rabbits. Steroids which reacted significantly with the antisera were found to be progesterone, pregnenolone, corticosterone and 11-oxo progesterone. However, after extraction of plasma and column chromatography on Celite, all these steroids were separated from 21-deoxycorticosterone and consequently did not interfere with the radioimmunoassay. The intra- and interassays coefficients of variation were 8% and 11% respectively. Mean plasma 21-deoxycorticosterone level for healthy subjects was very low: 17.8 +/- 14.8 pmol/l (mean +/- SD) with no statistical difference between males and females. During the ACTH stimulation test, the 21-deoxycorticosterone levels of healthy subjects increased to 84.7 +/- 26.3 pmol/l (mean +/- SD) for males and 79.3 +/- 31.6 pmol/l (mean +/- SD) for females. Consequently high levels of plasma 21-deoxycorticosterone were found in treated patients suffering from congenital adrenal hyperplasia (CAH) with 21-hydroxylase deficiency, particularly in CAH salt-losers with high plasma renin activity (PRA), where the plasma level reached 40,545 pmol/l. Thus, 21-deoxycorticosterone may be a new marker for adrenal 21-hydroxylase deficiency.

17-alpha-Hydroxyprogesterone↗
PubMed1987

Simultaneous radioimmunoassay of progesterone, androst-4-enedione, pregnenolone, dehydroepiandrosterone and 17-hydroxyprogesterone in specific regions of human brain.

Simultaneous determination of progesterone, androst-4-enedione, pregnenolone, dehydroepiandrosterone (DHEA) and 17-hydroxyprogesterone has been developed for human cerebral tissue. Before immunoassay, steroids were separated on a Celite column with propylene glycol as stationary phase with hexane containing increasing proportions of dichloromethane as mobile phase. This system allowed separation of steroids of similar polarity, especially of pregnenolone and progesterone. The brain regions studied cortex (prefrontal, parietal and temporal), cerebellum and corpus callosum, were obtained after autopsy from 9 women and 1 man between 76 and 93 years of age. Steroids were found in all regions. The overall concentrations expressed in nmol/kg of tissue were: 10.1, 7.6, 120.7, 19.6 and 10.4 respectively, for progesterone, androst-4-enedione, pregnenolone, dehydroepiandrosterone and 17-hydroxyprogesterone, corresponding to 7.3, 4.9, 74, 6.5 and 9.2 times the plasma levels. These very high concentrations, not previously described in human brain tissue, pose the question of the existence of local biosynthetic pathways independent of the peripheral endocrine gland system as well as that of progressive accumulation of steroids over a lifetime. Concentrations of each steroid in each subject varied little among the various brain regions studied, but there was much variation among the subjects with respect to the concentrations of a given steroid.

17-alpha-Hydroxyprogesterone↗
PubMed1987

Simple laboratory test of neuroendocrine disturbance in depression: 11 p.m. saliva cortisol.

Saliva cortisol was measured at 11 p.m. in a sample of 74 psychiatric inpatients composed of 24 primary endogenous depressives, 40 secondary depressives and 20 nondepressives (DSM III and Saint-Louis criteria). Primary depressives had significantly higher 11 p.m. saliva cortisol levels than nondepressives (p less than 0.02) and secondary depressives (p less than 0.05). In contrast, there were no significant differences between secondary depressive and nondepressive saliva cortisol levels. A saliva cortisol cutoff limit of 3.45 nmol/l identified primary depressives with a sensitivity of 62.5% and with a specificity of 75% in the depressive group, and 90% in the nondepressive group. The measurement of saliva cortisol at 11 p.m. could be used alone as a reliable and practical index of hypothalamic-pituitary-adrenal axis activity in depression, especially in outpatients.

Adolescent↗
PubMed1987

Design of antiandrogens and their mechanisms of action: a case study (anandron).

The design of a new drug is conditioned by knowledge of the biochemical mechanisms involved in the etiology of the disease to be treated. With regard to endocrine pathologies, such knowledge can be obtained in the clinic from systematic assays of urinary and plasma hormones, enzyme activities and target tissue receptor concentrations. The present paper describes the results of our assays of plasma 3 alpha-androstanediol glucuronide, 5 alpha-reductase and androgen receptor in prostate cancer patients. The activity of the nonsteroid antiandrogen anandron is discussed in relation to these parameters: anandron may inhibit slightly adrenal androgen biosynthesis but, in particular, counters the action of these adrenal androgens on the prostate. It does not inhibit rat prostate 5 alpha-reductase activity but interacts with androgen receptor to exert an antiandrogen action.

Androgen Antagonists↗