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Biomedical subjects

A Racadot

Publications and source records attributed to A Racadot.

At least 19 recordsLinked to original sources
PubMed1992

Normal hemodynamic and coagulation responses to 1-deamino-8-D-arginine vasopressin in a case of lithium-induced nephrogenic diabetes insipidus. Results of treatment by a prostaglandin synthesis inhibitor (indomethacin).

The effect of 1-deamino-8-D-arginine vasopressin (DDAVP) on mean arterial pressure, pulse rate (PR), plasma renin activity (PRA), plasma factor VIIIc and von Willebrand factor were studied in a case of persistent lithium-induced nephrogenic diabetes insipidus (LINDI). 20% decrease in MAP, 22% increase in PR, 100% in PRA, and release of coagulation factors (2- to 3-fold) were noticed after infusion of 0.3 micrograms/kg DDAVP. Urinary prostaglandin (PG) E2 were enhanced. The treatment of this LINDI by PG synthesis inhibitor (PSI) combined with a low osmotic diet (LOD) led to a 51% fall in urine volume, 57% in free water clearance and 75% in sodium clearance. Urinary osmolality rose by 42% but remained low, probably in part because of the LOD. Urinary PGE2 was about one fifth of the initial high value. The results argue for (1) an end-organ resistance to DDAVP confined to the kidneys in LINDI and (2) an effectiveness of indomethacin combined with an LOD.

Adult↗
PubMed1992

Estradiol, progesterone and testosterone exposures affect the atrial natriuretic peptide gene expression in vivo in rats.

To clarify the effects of sex hormones on the expression of atrial natriuretic peptide (ANP), ovariectomized and intact female rats were subcutaneously injected with estradiol, progesterone, a mixture of them or olive oil solvent; castrated and untouched male rats were subcutaneously injected with estradiol, testosterone or olive oil, once a day for 7 days. The relative rANP-mRNA contents of rat atrial were measured by molecular hybridization. rANP-cDNA was labeled with 32P as a probe. The results revealed that estradiol and progesterone increased ANP gene expression. Furthermore their effects were associated with administration dose of these hormones and it was shown that they are probably coordinated. The physiological amounts of estradiol and progesterone may maintain suitable levels of rANP-mRNA and androgen may also increase the ANP gene expression in vivo. These experiments suggested that female sex hormone may have a dual purpose in fluid balance.

Animals↗
PubMed1992

Decrease of testosterone level during an experimental African trypanosomiasis: involvement of a testicular LH receptor desensitization.

To investigate gonadal disorders and changes of the testicular receptors occurring during the sleeping sickness disease (African trypanosomiasis), an experimental model was developed with 10-month-old rats infested by bloodstream forms of two variants of Trypanosoma brucei brucei (AnTat 1.1 A and AnTat 1.8). At the acute phase, three days after inoculation, the animals were sacrificed for estimating the serum levels of LH and testosterone and the number of testicular LH receptors. Considering a possible intervention of the stress during the infestation and to improve our investigations on gonadal imbalance related to trypanosomasis, levels of additional parameters [corticosterone, glucose and transaminases (glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase)] were determined. Stimulation testing with hCG was likewise assessed in infested rats to analyse the testicular testosterone response to gonadotropin. A significant decrease was demonstrated for serum LH and testosterone levels in the infested rats, as well as the loss of: (i) the testicular responsiveness to exogenous gonadotropin; (ii) the number of testicular LH receptors. Moreover, the remaining testicular receptors of infested rats showed an increase in their equilibrium association constant (Ka). Our study suggests that dysfunction of Leydig cells occurring during African trypanosomiasis is in part related to stress induced by the presence of the parasites.

Acute-Phase Reaction↗
PubMed1991

Usefulness and limits of quick intraoperative measurements of intact (1-84) parathyroid hormone in the surgical management of hyperparathyroidism: sequential measurements in patients with multiglandular disease.

This study was designed to assess whether reliability of quick intraoperative assay of intact (1-84) immunoreactive parathyroid hormone (iPTH) could allow us to quit after removing one (or several) enlarged parathyroid gland(s) and obtaining a normal iPTH level. Intact iPTH was assayed during surgery before removal of enlarged parathyroid gland(s) and 5, 10, and 20 minutes afterward. Forty-seven patients entered the study: 40 with primary hyperparathyroidism (32 with uniglandular disease and eight with multiglandular disease) and seven with secondary hyperparathyroidism; all underwent bilateral neck exploration. Among 32 patients with uniglandular disease, five had normal basal intraoperative levels, 25 demonstrated a clear-cut drop from supranormal to normal levels, and two had elevated levels. Among the eight patients with multiglandular disease, two had undetectable levels and two had normal levels after removal of the first enlarged gland. The seven patients with secondary hyperparathyroidism demonstrated a decline in PTH levels, suggesting hormone clearance similar to that of patients with primary hyperparathyroidism. In conclusion, quick intraoperative assay with intact (1-84) iPTH (1) is not hampered by renal insufficiency, (2) may overlook a second enlarged gland after removal of a first adenoma and obtaining normal iPTH levels, and (3) should not be used as a substitute for bilateral neck exploration.

Humans↗
PubMed1991

[Pseudo-hyperkalemia. Apropos of a familial case].

One case of pseudo-hyperkalaemia is reported in a women who suffered of labile hypertension and was previously treated by fluorohydrocortisone because of hyperkalaemia. Clinical examination and ECG were normal. An incubation test performed at different temperatures confirmed the diagnosis. There was no haematological abnormality. Familial screening prompted us to discover 2 affected subjects among four studied, according to autosomal dominant inheritance. This abnormality was due to increased passive membrane permeability to potassium at low temperature out of any hematological syndrome. The diagnostic is important to avoid inappropriate medications.

Aged↗
PubMed1990

[Macroprolactinemia in a child].

An hyperprolactinemia, with basal serum prolactin levels ranging from 41 to 135 ng/ml was found to be coincidentally associated with psychosocial dwarfism in a 11 year-old boy. Sephadex G 100 exclusion chromatography showed that the predominating form of immunoreactive prolactin levels ranging from 41 to 135 ng/ml was found to be weight, differing from the regular occurrence of a 22 kilodalton major variant. Prolactin levels increased under TRH (increments between 29 and 76%) but were not blunted by bromocriptine at a dose of 2.5 mg/day. This so-called macroprolactinemia syndrome should be searched for whenever a discrepancy is noted between clinical symptoms and blood prolactin levels.

Adolescent↗
PubMed1990

[Gonadotropic adenoma. Clinical and hormonal characteristics].

The main clinical and hormonal features of gonadotropin secreting adenomas (GSA) are reviewed through the literature and our personal data. There is still no agreement about their definition and frequency. The most classical clinical presentation is that of men aged 50 years or more, bearing a large pituitary adenoma, the only biological expression of which is a moderately elevated serum FSH level. Female cases are less recognised and are underestimated because the serum LH and/or FSH elevated levels are not informative in menopausal women. The assay of the alpha subunit may help in these cases. In premenopausal women, few of them having been described so far, the GSA may be revealed by an amenorrhea-galactorrhea syndrome with a mild hyperprolactinaemia which may result from different mechanisms. The absence of gonadal hyperactivity, and, conversely, the frequent hypogonadism associated with GSA lead the clinician to raise some questions: are all GSA able to secret gonadotropins? How is the bioactivity of the LH and/or FSH secreted by GSA? How reliable are the radioimmunoassays routinely used for measurement of LH and FSH in patient's serum? Furthermore, therapeutical management of GSA is still impaired by the lack of documented medical treatments which could control their growth and prevent their recurrence.

Adenoma↗
PubMed1989

Altered erythrocyte cation permeability in familial pseudohyperkalaemia.

1. Erythrocyte cation transport pathways have been investigated in a family with pseudohyperkalaemia. 2. Ouabain- and bumetanide-resistant Na+ and K+ effluxes in three pseudohyperkalaemic patients were not different from those of control subjects when assessed at 37 degrees C. 3. When the temperature was decreased to 20 degrees C and 9 degrees C, K+ passive permeability markedly increased and Na+ permeability remained unchanged in these patients. In contrast, in control subjects a reduction in temperature caused a marked reduction in Na+ and K+ passive permeability. 4. These findings could account for the marked increase in plasma K+ concentration observed at subphysiological temperatures. 5. The Na+-K+ co-transport pathway was reduced in all members of the family, but the Na+-K+ pump was reduced in only two of them. These alterations were independent from the pseudohyperkalaemic state.

Aged↗
PubMed1989

Adrenocorticotropin and cortisol responses to ovine corticotropin-releasing factor in alcohol dependence disorder. Preliminary report.

A 100-micrograms bolus of synthetic ovine corticotropin-releasing factor was administered intravenously to 10 nondepressed inpatients suffering from an alcohol dependence disorder. The test was performed during withdrawal and after 4 weeks of abstinence. During withdrawal, the plasma cortisol responses of alcoholic patients and 7 control subjects were similar, except for an earlier decrease of cortisol in the former group. However, after 4 weeks of abstinence, the cortisol response was significantly lower in alcoholic patients than in controls. These abnormalities observed during discontinuance of alcohol consumption may reflect adaptive mechanisms of the hypothalamic-pituitary-adrenal activity which may be previously altered by chronic alcohol intoxication.

Adrenal Cortex↗
PubMed1989

[Enkephalin-like immunoreactivity in Leydig cell tumor].

So far, the presence of an enkephalin-like immunoreactivity has never been reported in Leydig cell tumors at our knowledge. A 39 years old man having a painful gynecomastia and an impotency changing in time has been studied. At clinical examination, he was normal, without palpable testis tumor. The sperm count analysis showed an oligoastheno-spermia. Plasma testosterone (T) was low and plasma estradiol (E2) was high, varying from day to day. T/E2 ratio was always low (20 to 72 - N:220-240) and fell after HCG administration. Plasma LH was normal and plasma FSH was low. 17 hydroxyprogesterone (17 OH-P)/T ratio was increased (0.7 - N:0.23). A small tumor was localized in the left testis by ultrasonography. The spermatic vein catheterization, which was only possible on the left side, showed a decreased T, a high E2 and a low T/E2 ratio (19 - N:304). After unilateral orchidectomy, the histological study confirmed the diagnosis of Leydig cell tumor. With antibodies raised against synthetic Met-en-kephalin, it has been possible to detect an enkephalin-like immunoreactivity in the tumoral cells as well as in the surrounding normal cells.

Adult↗
PubMed1989

Gonadotropic axis and Trypanosoma brucei gambiense infection.

A gonad endocrine survey on 46 Congolese patients (15 women and 31 men) with parasitologically confirmed trypanosomiasis found amenorrhoea in 60% of the women and impotence in 70% of the men. The basic gonad endocrine examination showed a decrease in oestradiol levels in about 65% of the women. Both amenorrhoea and low oestrogen levels were observed in the second phase (P2) of the disease, but low oestrogen levels were sometimes noted in the first phase of the disease (P1). In the men, about 50% of the cases (P2) showed a decrease in testosterone. However, as in the women, the variation of testosterone was also observed in the first phase (P1). A static and dynamic examination of the hypothalamic-pituitary-gonadal axis was undertaken in order to investigate the origin of these hypogonadisms. A supra - or extra-hypophyseal origin is discussed.

Adolescent↗
PubMed1988

[Hyperreninemic hypoaldosteronism syndrome induced by plasma exchange].

The study was designed to measure sequential changes in plasma renin activity, aldosterone, angiotensin-converting enzyme activity and ionograms, prior to, and after therapeutic plasma exchange. Each measurement was repeated before and after stimulation of renin activity induced by furosemide. The results showed that plasma exchange induces a syndrome of hyperreninemic hypoaldosteronism associated with a depletion in angiotensin-converting enzyme activity which might account for the dissociation between plasma renin activity and aldosterone.

Adolescent↗
PubMed1988

Screening heterozygotes for 21-hydroxylase deficiency among hirsute women: lack of utility of the adrenocorticotropin hormone test.

Heterozygosity for 21-hydroxylase deficiency (21-OHD) was investigated in 174 adult hirsute women by using the sum of the incremental responses of serum 17 alpha-hydroxyprogesterone (17 alpha-OHP) and progesterone (P) (delta 17 alpha-OHP + P), 60 minutes after a 0.25 mg intravenous (IV) bolus of synthetic adrenocorticotropic hormone (ACTH). The distribution of 17 alpha-OHP + P in hirsute women was bimodal, allowing two subgroups to be distinguished. In one subgroup including 137 patients, the mode was similar to controls and all values were lower than 3 ng/ml. Thirty-seven (21%) patients constituted another subgroup with values higher than 3 ng/ml and could a priori have been considered as heterozygotes for 21-OHD. However, human leukocyte antigen genotyping provided no conclusive evidence that this subgroup included exclusively heterozygotes for the 21-OHD.

17-alpha-Hydroxyprogesterone↗
PubMed1988

Decrease of angiotensin-converting enzyme activity after plasma exchange.

We measured sequential changes in serum angiotensin-converting enzyme (ACE) in 12 ICU patients undergoing plasma exchange (PE) with plasma substitutes (albumin-Polygelin). A dramatic decrease in serum ACE activity was observed after each of the 51 PE procedures. Repeated PE procedures resulted in almost a total depletion of serum ACE, which returned to normal ranges in 4 to 10 days. No ACE change was observed during hemodialysis or hemofiltration. ACE activity increased after PE with fresh frozen plasma replacement. ACE changes were compared with IgG, antithrombin III, and fibronectin changes. Extraction ratio comparisons were consistent, with a loss in removed plasma accounting for 50% to 70% of the observed ACE decrease. Plasma zinc levels were not modified after PE. Mixing experiments with increasing volumes of plasma substitutes showed ACE inhibition by Polygelin. In vivo infusion of Polygelin had the same effect. The renin-induced aldosterone response studied in six exchanged patients was consistent with a relative hyperreninemic hypoaldosteronism after repeated PE. These findings may be of clinical relevance during acute hypovolemia and dehydration after PE or Polygelin infusion and in patients with impaired lung endothelial function.

Adult↗
PubMed1988

[Endocrine function and African trypanosomiasis. Evaluation of 79 cases].

Although the high frequency of hypogonadism was found during the sleeping sickness, the physiological properties of the gonads have been poorly studied. We reported here the exploration of the gonadotropic axis in 79 patients infected by Trypanosoma brucei gambiense. It has been noted a decrease in oestradiol for 50% of women, in testosterone levels for 50% of men whereas no decrease of pituitary gonadotropins (FSH and LH) was found. The results of the gonad adenohypophyseal tests suggested that the dysfunction may be of central origin. The studies of thyreotropic axis were also examined: a decrease in T3 and FT3 (free fraction) even though T4 was normal. The specific relationship between hypogonadism and trypanosomal infection is discussed in this report.

Adolescent↗
PubMed1986

A double blind controlled study of the hormonal and clinical effects of bromocriptine in the polycystic ovary syndrome.

Previous studies on the efficacy of bromocriptine for the treatment of patients with the polycystic ovary syndrome failed to include control groups. This study, therefore, was undertaken to determine the clinical and endocrine effects of bromocriptine and a placebo (given in a random double blind fashion) in 55 patients with PCOS. The plasma levels of estrone, estradiol, testosterone, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, 17-hydroxyprogesterone, and serum PRL and gonadotropins (LH and FSH) were measured before treatment. In addition the serum PRL response to TRH and the serum LH and FSH response to GnRH were determined. The effects of acute administration of bromocriptine (2 X 2.5 mg at 12-h intervals) on serum gonadotropins and their response to GnRH were studied to explore the possibility that this test might predict the response to chronic bromocriptine treatment. Bromocriptine then was given at an initial dose of 1.25 mg twice daily. If no clinical improvement occurred 2.5 mg were given twice daily for at least 6 months. Hormonal measurements and dynamic tests were repeated after 3 and 6 months of therapy. The endocrine profile of the two groups was not different before treatment. The clinical results were not better in the treatment group than in the placebo-treated patients: therapy was successful (restoration of ovulatory cycles of less than 35 days duration) in 12 of 28 patients taking bromocriptine vs. 8 of 27 taking placebo. Slight improvement (1 or 2 ovulations) occurred in 3 of 28 vs. 3 of 27, and failure (no clinical change) in 13 of 28 taking bromocriptine vs. 16 of 27 taking placebo, respectively. Serum PRL fell significantly in the bromocriptine group, and there was a significant fall in the serum LH response to GnRH in both groups. No hormonal measurement or response predicted the clinical response to treatment. The only significant effect of chronic bromocriptine therapy (5 mg/day) in patients with the polycystic ovary syndrome was to lower the serum PRL concentration.

Adolescent↗
PubMed1986

Clinical and biological phenotypes in late-onset 21-hydroxylase deficiency.

We analyzed data from 20 patients with late-onset 21-hydroxylase deficiency (LOHD). Three clinical phenotypes could be distinguished among the 18 women. Seven (39%) presented with clinical features suggesting polycystic ovarian disease (PCOD). However, despite androgen levels similar to those of patients with typical PCOD, high serum LH to FSH ratios were not consistently found. Seven other women (39%) presented with isolated hirsutism, suggesting idiopathic hirsutism. The remaining 4 women (22%) had no manifestations of androgen excess and were considered to have the cryptic form of LOHD. Serum 17-hydroxyprogesterone (17-OHP) and androgen levels were similar in the 3 phenotypes, suggesting that the clinical expression of LOHD in women is modulated by individual factors, such as androgen sensitivity. The 2 men were detected by family study and were clinically normal. Since clinical diagnosis of LOHD is impossible, we concentrated on hormonal data with the aim of providing guidelines for the biological diagnosis of LOHD. Assay of basal serum 17-OHD at 0800 h in both sexes and in the early follicular phase in women was sufficient to establish the diagnosis of LOHD in most patients. If doubtful results are obtained, i.e. serum 17-OHP levels between 2 and 5 ng/ml, an ACTH test must be performed. Post-ACTH serum 17-OHP levels exceeding 10 ng/ml confirm the diagnosis of LOHD. Such results should avoid confusion with heterozygotes for 21-hydroxylase deficiency, whose frequency is high within the general population and may be even higher in patients with idiopathic hirsutism or PCOD.

17-alpha-Hydroxyprogesterone↗