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Biomedical subjects

H Dechaud

Publications and source records attributed to H Dechaud.

50 records · Page 3Linked to original sources
PubMed1985

Determination of plasma testosterone by mass fragmentography using [3,4-13C]testosterone as an internal standard.

The combination of glass capillary gas chromatography--mass spectrometry is especially suitable for the recognition of compounds. The use of [3,4-13C]testosterone as internal standard, mass fragmentography and isotope ratio measurement have been applied to the quantitative determination of testosterone in plasma. This paper describes the method, using tert.-butyldimethylsilylmethoxime and di-heptafluorobutyrate derivatives. The calibration graph in isotopic dilution is examined. The results obtained are compared with the results obtained by radioimmunoassay. The sensitivity of the method is judged from the lower limit of detection: 4.5 pg. The precision, and inter- and intra-assay are calculated.

Dehydroepiandrosterone↗
PubMed1985

Daily variations of plasma sex hormone-binding globulin binding capacity, testosterone and luteinizing hormone concentrations in healthy rested adult males.

In this study the daily variations of plasma sex hormone-binding globulin (SHBG) binding capacity were measured together with plasma testosterone and luteinizing hormone (LH) concentrations in 7 healthy rested adult males. Plasma SHBG-binding capacity demonstrated a significant circadian rhythm (acrophase = 2.06 p.m.; mesor = 0.35 +/- 0.6 ng testosterone bound/100 ml; amplitude = 17% of the mesor). Plasma testosterone also showed a circadian rhythm (acrophase = 7.02 a.m.; mesor = 4.38 +/- 0.67 ng/ml; amplitude = 18% of the mesor). The free testosterone index (or the ratio between plasma testosterone and SHBG-binding capacity) was not correlated with plasma LH levels. In our hands this last parameter did not vary according to a circadian pattern. These data are discussed in terms of a feedback mechanism controlling the pituitary-testis axis regulation.

Adult↗
PubMed1985

Beta-lipotropin and cortisol responses to an intravenous infusion dexamethasone suppression test in Cushing's syndrome and obesity.

An i.v. infusion dexamethasone (Dex) test was used to investigate the ACTH feedback response in 9 normal subjects, 12 obese patients, and 11 patients with Cushing's syndrome. Dex phosphate was infused iv for 4 h, starting at 1100 h (1 mg/h). Plasma concentrations of beta-lipotropin (beta LPH) and cortisol were measured every 20 min between 0900 and 1600 h, then every 2 h until midnight and at 0900 h the next day. In normal subjects and obese patients, plasma beta LPH and cortisol concentrations fell rapidly to less than 40 ng/liter and 3 micrograms/dl, respectively, at the end of Dex infusion. Subsequent values remained low through 0900 h the next day. In 7 patients with Cushing's disease, basal plasma beta LPH and cortisol concentrations declined by greater than 50% during the Dex infusion. In these patients, rapid escape from suppression occurred between 1600 and 2400 h; by 0900 h the following day, beta LPH and cortisol levels were higher than 100 ng/liter and 10 micrograms/dl, respectively. In 3 patients with adrenal tumors, beta LPH concentrations were low, and cortisol concentrations did not decline during the Dex infusion. In 1 patient with ectopic ACTH secretion, beta LPH concentrations were high and were not suppressed by the Dex infusion. We conclude that the iv infusion Dex suppression test can distinguish patients with Cushing's syndrome from normal or obese subjects and can aid in the etiological diagnosis of Cushing's syndrome.

Adult↗
PubMed1985

Lack of beta-adrenergic role for catecholamines in the development of hyperglycemia and ketonaemia following acute insulin withdrawal in type I diabetic patients.

In order to evaluate the role of beta-receptor mediated effects of catecholamines in the metabolic deterioration following insulin withdrawal in insulin-dependent diabetic patients we have measured in 5 patients metabolic substrate and hormone concentrations during a 6 hours arrest of insulin infusion, without or with a simultaneous infusion of propranolol. During insulin deprivation plasma epinephrine and norepinephrine increased slightly (from 107 +/- 10 ng/L to 173 +/- 6 ng/L and from 307 +/- 37 ng/L to 518 +/- 77/ng/L respectively (p less than 0.05), cortisol decreased physiologically, but growth hormone and glucagon were not significantly modified. Free insulin decreased progressively from 12.2 +/- 2.5 mU/L to 5.4 +/- 1.1 mU/L (p less than 0.01). Blood glucose and ketone bodies rose sharply before any significant change in catecholamine levels. Plasma free fatty acids and blood glycerol increased progressively and their rise appeared somewhat temporally related to the variations of catecholamine levels. The addition of propranolol to insulin deprivation did not modify the changes in hormone concentrations in spite of a slightly greater rise of epinephrine (from 78 +/- 4 ng/L to 179 +/- 7 ng/L, p less than 0.05) and norepinephrine (from 395 +/- 80 ng/L to 679 +/- 153 ng/L, p less than 0.05). The rises of glucose and ketone bodies were unaffected whereas the increases of free fatty acids and glycerol were slightly blunted. In conclusion, we have no evidence for a beta-adrenergic mediated role for catecholamines in the development of hyperglycaemia and ketonaemia in non-stressed insulin deprived diabetic patients, and only small evidence for a permissive effect on lipolysis.

Adult↗
PubMed1985

[Evolution of plasma levels of SHBG (sex-hormone binding globulin) during ovulation induction using gonadotrophins].

The plasma levels of proteins bound to steroids come under the influence of the levels of estrogens. This is why we have studied the changes in plasma SHBG in sterile women who were being treated by gonadotropins (HMG-HCG). The plasma level of SHBG was worked out using Laurell's electroimmunoassay technique with an autoradiographic display using estradiol labeled with I.125. It only takes 48 hours contact with radio films. Out of 12 patients 9 responded to the treatment as demonstrated by the plasma levels of estradiol (E2) and progesterone (P). We have found that in these women there was a rise in plasma SHBG which was significant from the 7th day of the treatment onwards (3.7 +/- 1.7 mg/l as against 5.9 +/- 2.6 mg/l, p less than 0.01) and this reached nearly twice the base level when E2 reached its maximum level (6.4 +/- 2.7 mg/l). When treatment was stopped the plasma level of SHBG dropped to that of the follicular phase, but it was out of step with the plasma E2 levels. The index of free E2 as compared with E2/TEBG showed a close superimposition when compared with the levels of E2 obtained using a radioimmunological method. This fact reinforces the value of plasma E2 as the way of monitoring the effect of induction of ovulation. Our overall conclusion is that a marked and rapid change in the level of plasma E2 directly influences the level of plasma SHBG. The consequences for treatment are that it is important to respect as far as possible the physiological conditions that are present when induction of ovulation is undertaken.

Estradiol↗
PubMed1984

Increased plasma concentration of N-terminal beta-lipotrophin and unbound cortisol during pregnancy.

The plasma concentration of N-terminal beta-lipotrophin (beta-LPH), total and protein unbound cortisol, progesterone and the transcortin (CBG) binding parameters have been measured in 21 women in the early follicular phase and in 70 pregnant women at various stages of pregnancy. Results showed that the plasma CBG binding capacity and the concentrations of total cortisol and progesterone increased significantly at each trimester of pregnancy while the plasma concentration of unbound cortisol increased significantly only in the 2nd and the 3rd trimesters of pregnancy. In addition, a significant increase of N-terminal beta-LPH level was observed during the 3rd trimester. By chromatography, it is demonstrated that during the 3rd trimester of pregnancy the beta-LPH/gamma-LPH molar ratio decreases dramatically and that the increase of N-terminal beta-LPH concentration is mainly due to a two fold increase in gamma-LPH concentration.

Female↗
PubMed1984

Acute dopaminergic blockade by sulpiride stimulates beta-endorphin secretion in pregnant women.

The pars intermedia of the pituitary gland is well developed in most animal species but rudimentary in adult human subjects. Unlike the anterior pituitary, the intermediate lobe metabolizes proopiomelanocorticotrophin (POMC) mainly to beta-endorphin and to alpha-melanotrophin (alpha-MSH). This activity of the pars intermedia is under an inhibitory dopaminergic control. Biochemical and immunohistochemical evidence suggests the hyperplasia of the intermediate lobe during human pregnancy. The present study demonstrates that an acute dopaminergic blockade by sulpiride dramatically increases plasma concentrations of beta-endorphin in pregnant women but not in non-pregnant women providing functional evidence for the intermediate lobe hypothesis.

Adult↗
PubMed1984

The value of beta-lipotrophin measurement during the short metyrapone test in patients with pituitary diseases and in Cushing's syndrome.

Serum 11-deoxycortisol (S) determination has been used to evaluate the pituitary adrenal response to the short metyrapone (MTP) test. The validity of this indirect evaluation of corticotrophin ACTH reserve has been questioned since the MTP-induced S elevation may reflect a passive accumulation rather than an ACTH activated adrenal response. The purpose of this study was to evaluate the usefulness of serum beta-lipotrophin (beta-LPH) measurement during the short midnight MTP test (30 mg/kg body weight) in patients with pituitary diseases (n = 36) and in patients with Cushing's syndrome (n = 8). In 28/36 patients with pituitary diseases both S and beta-LPH concentrations were increased normally by MTP. In 8/36 patients the beta-LPH response was lacking, while their serum S concentrations increased significantly. The absence of beta-LPH response to MTP in these 8 patients was in good agreement with the diagnosis of ACTH insufficiency because in 7 of them the cortisol response to insulin induced hypoglycaemia was also insufficient. In the 8 patients with Cushing's syndrome serum S concentration increased following MTP administration in all the cases. In 2 with adrenal adenoma the increase of S level was an ACTH-independent phenomenon, since beta-LPH level was undetectable both before and after MTP administration. In 2 patients with ectopic ACTH secretion, the basal beta-LPH concentrations were high and remained unmodified by MTP administration. In the 4 patients with Cushing's disease, MTP administration resulted in a dramatic increase of beta-LPH concentration. We conclude that beta-LPH measurement improves the utility of the short MTP test for investigation of pituitary adrenal function.

Adrenocorticotropic Hormone↗
PubMed1980

[Genetic deficiency of thyroxin-binding protein in 4 members of a family (author's transl)].

Four members of the same family (2 male and 2 female) with normal thyroid function were found to have decreased total T3 and total T4, elevated response to the T3 test and low free thyroxin index. Such biological changes result from a deficiency in carrier protein and should be distinguished from nearly similar abnormalities observed in low T3 syndrome and hypothyroidism. Whilst gonosomal transmission through the X chromosome of thyroxin-binding protein deficiency seems well established, our findings show that another mechanism, i.e. dominant autosomal heredity, is practically certain.

Alpha-Globulins↗
PubMedDate not supplied

First-trimester multifetal pregnancy reduction: evaluation of technical aspects and risks from 2,756 cases in the literature.

OBJECTIVE: To evaluate the technical aspects, efficacy and safety of first-trimester multifetal pregnancy reduction in the management of multifetal pregnancies, an analysis of the international literature on first-trimester multifetal pregnancy reduction was made. MATERIALS: Thirty-three studies were selected from an international review of the literature. Total fetal loss rate, risk of fetal loss after the procedure with the different techniques and gestational age at delivery were the main parameters studied. The Kruskal-Wallis test and Mann-Whitney test were used for statistical analysis. RESULTS: 2,756 multifetal pregnancy reductions were performed (2,145 transabdominal, 363 transcervical, and 248 transvaginal procedures). Total fetal loss rates were different: 16.7% for the transabdominal, 24.8% for the transcervical and 10.9% for the transvaginal procedure (p = 0.03). The risk of fetal loss was 12% for the transabdominal, 20% for the transcervical, and 10% for the transvaginal approach at less 24 weeks of gestation (p = 0.04). There was no difference for the gestational age at the time of the procedure, the initial and final number of embryos, and the gestational age at delivery. CONCLUSION: Because the transvaginal approach seems to be the safer procedure, surgeons may opt for it. The transcervical approach has a high fetal loss rate and should be excluded.

Abortion, Spontaneous↗
PubMedDate not supplied

[Luteal insufficiency and elevation of sex-binding proteins by demegestone].

Demegestone, a norprogesterone derivative, was administered during the luteal phase in 6 normally ovulatory women and in 10 patients with luteal insufficiency. Demegestone decreased the LH surge and the plasma concentrations of estradiol and progesterone in the normally ovulatory women and did not modify the binding capacity of sex steroid binding protein (SBP). In the patients with luteal insufficiency, demegestone increased significantly SBP (0.94 +/- 0.24 vs 1.32 +/- 0.56 micrograms/dl, p less than 0.05) and decreased the free testosterone index (T/SBP) (38.8 +/- 33.3 vs 25.4 +/- 18.5, p less than 0.05). Transcortin, was unchanged during demegestone treatment in both groups of women. The results showed that demegestone did not exercise androgenic activity on SBP conversely to the nortestosterone derivatives which decrease SBP and confirmed that progesterone and norprogesterone derivatives influence positively the regulation of SBP.

Adult↗
PubMedDate not supplied

Insulin-mediated glucose disposal in type 1 (insulin-dependent) diabetic subjects treated by continuous subcutaneous or intraperitoneal insulin fusion.

In order to determine if intraperitoneal insulin infusion could improve the insulin resistance of type 1 diabetic patients we have used the englycaemic insulin clamp technique in order to study the effects of insulin on glucose disposal in four C peptide negative type 1 diabetic patients treated by continuous subcutaneous or intraperitoneal insulin infusion and in five control subjects. Compared to control subjects, the diabetic patients treated by subcutaneous insulin infusion had a decreased maximal capacity of glucose utilization (diabetics: 12.6 +/- 0.3 mg.kg-1.min-1; controls: 15.7 +/- 0.7 mg/kg-1.min-1, p less than 0.01) and a trend towards higher half-maximally effective insulin concentrations (diabetics: 70 +/- 11 mU/l-1, controls: 48 +/- 4 mU/l-1). Treatment of the diabetic patients by intraperitoneal insulin infusion for 2 months decreased their mean peripheral free insulin levels (during subcutaneous infusion: 23.5 +/- 2.2 mU/l-1; during intraperitoneal infusion: 18.4 +/- 1.4 mU/l-1, p less than 0.05). However, mean daily insulin requirements were not decreased (during subcutaneous infusion: 0.59 +/- 0.05 U/kg-1.day-1; during intraperitoneal infusion: 0.57 +/- 0.03 U/kg-1.min-1). Moreover, the diabetic patients had a consistently lower maximal capacity of glucose utilization (12.6 +/- 0.7 mg kg-1.min-1) than control subjects (p less than 0.01) without modification of the half-maximally effective insulin concentration (62 +/- 10 mU.l-1). In conclusion, the only benefit of intraperitoneal insulin infusion was a reduction of peripheral free insulin levels; this decrease of peripheral insulinaemia was not associated with an improvement in the insulin resistance of diabetic patients.

Adult↗
PubMedDate not supplied

[Fallopian tube endoscopy in 1996].

AIM: To establish the statement in 1996 of the exploration of the Fallopian tubes by falloposcopy in the framework of the tubal or unexplained sterility. MATERIAL AND METHODS: The feasibility of the method, the endotubal aspect and the potential contribution of the falloposcopy in the exploration of the tubes of infertile women were analyzed from a review of the literature and a personal experience of 145 tubal endoscopies. RESULTS: Tubal catheterism rate is 91%; duration of the exploration varies from 30 to 40 minutes and decreases with the experience of the surgeon. The tubal lumen is explored correctly on all its length in more of 71% of cases. The tubal complications represented by perforations occur in 5% of cases and essentially on pathological tubes. False-negative and false-positive rates of the couple hysterosalpingography/laparoscopy are respectively 57 and 17% as compared to the falloposcopy. CONCLUSION: The falloposcopy is a safe and reproductible method. The exploration of Fallopian tubes by this technique dressed more precise than that obtained from indirect manner by known examinations that are hysterosalpingography and the laparoscopy.

Endoscopy↗