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D Dewailly

Publications and source records attributed to D Dewailly.

At least 55 records · Page 3Linked to original sources
PubMed1994

Ovarian stromal hypertrophy in hyperandrogenic women.

OBJECTIVE: By using vaginal endosonography, ovarian stromal hypertrophy has been shown to be a strong diagnostic feature of polycystic ovarian syndrome and related states. However, this sign is difficult to quantify and to correlate with other findings because of its subjectivity. We have evaluated the use of computer assisted analysis of ultrasound scans to provide more objective measurements of ovarian structure and size. DESIGN: We used a computer assisted method for the reading of ultrasound scans. It allowed selective calculation of the stromal area by subtraction of the cyst area from the total ovarian area on a longitudinal ovarian section. PATIENTS: A consecutive series of 57 patients with hyperandrogenism (group 1), 17 patients with hypothalamic anovulation (group 2) and 20 normal women (group 3). RESULTS: By computerized measure, 75% patients from group 1 had a bilateral stromal area above the mean +2 SD (700 mm2) of women from group 3. All patients from group 2 were below this threshold. Serum LH level was above the normal range in 45% patients from group 1. The stromal area correlated positively with the serum delta 4-androstenedione (r = 0.47, P < 0.005) and 17 alpha-hydroxyprogesterone (r = 0.39, P < 0.005) levels, exclusively in group 1. It did not correlate with the basal serum testosterone, LH or insulin levels. The cyst area did not correlate with any hormonal parameter. CONCLUSION: Ovarian stromal hypertrophy is a frequent and specific feature of hyperandrogenism. It correlates with the ovarian androgenic dysfunction. Its presence is not always linked with elevated serum immunoreactive LH levels. Further data are needed to elucidate the role of insulin and ovarian growth factors.

17-alpha-Hydroxyprogesterone↗
PubMed1994

Decreased expression of the two D2 dopamine receptor isoforms in bromocriptine-resistant prolactinomas.

Bromocriptine or other dopamine agonists are usually effective for the treatment of prolactin-secreting adenomas. Five to 18% of prolactinomas, however, do not respond to such therapy. We have shown previously that such resistance to bromocriptine correlates with reduced binding to the D2 receptor subtype of dopamine, the major PRL inhibiting factor. In the present work, we demonstrated that reduced binding actually corresponds to decreased expression of the gene coding for the D2 receptor in the pituitary from bromocriptine-resistant patients, as shown by 4-fold lower levels of the corresponding mRNAs compared to those coding for actin. The existence of two D2 receptor isoforms, D2S and D2L generated by alternative splicing, has been described in several tissues, including the pituitary. Both are negatively coupled to adenylyl cyclase and inhibit prolactin secretion, but, in addition, the shortest one (D2S) is more efficiently coupled to phospholipase C. Consequently, we also investigated whether expression of a particular D2 receptor isoform was preferentially affected in resistant adenomas. The proportion of messengers corresponding to the short receptor isoform (D2S) was lower in resistant compared to responsive adenomas: D2S/D2L = 0.74 +/- 0.08 and 1.00 +/- 0.07, respectively. In parallel, much lower levels of D2 receptor mRNAs were found in growth hormone-secreting adenomas, with a D2S/D2L ratio comparable to those of both normal human pituitary and bromocriptine-sensitive prolactinomas (1.05 +/- 0.11). Thus, resistance to bromocriptine therapy seems to involve defects in D2 dopamine receptor expression and possibly in posttranscriptional splicing.

Adenoma↗
PubMed1994

[Does the endocrinal milieu influence the expression and/or the action of ovarian growth factors in polycystic ovary syndrome?].

Polycystic Ovary Syndrome (PCOS) results from endocrine, paracrine and autocrine dysfunction, affecting thecal and granulosa cells. The circulating insulin/IGF system is often dysregulated in PCOS. It could influence the local IGFs/IGF-BPs system, when granulosa, and more putatively thecal cells depend on. It is a new field of research about the physiopathology of PCOS, lying on clinical grounds. However, its practical interest is still limited.

Female↗
PubMed1993

Interrelationship between ultrasonography and biology in the diagnosis of polycystic ovarian syndrome.

In order to compare the diagnostic significance of hormonal and ultrasonic criteria of polycystic ovarian syndrome (PCOS), the presence or the absence of ultrasonographic and hormonal features of PCOS were recorded in a heterogeneous population of 90 women presenting with hyperandrogenism and/or menstrual disorders. On clinical and hormonal grounds exclusively, these patients could be separated into five diagnostic subgroups: presumed cases of PCOS (n = 21), idiopathic hirsutism (IH) (n = 26), hypothalamic anovulation (HA) (n = 11), hyperprolactinemia (HPRL) (n = 9), and miscellaneous or undetermined diagnosis (n = 23). By the means of a computed automatic classification of patients (cluster analysis) using five hormonal and ultrasonic criteria of PCOS, four homogeneous clusters of patients were obtained. Cluster #1 (25 patients) had the most characteristic profile of PCOS. It included 15 cases of PCOS and 7 cases of IH. Cluster #4 (47 patients) had the less characteristic profile of PCOS. It included the majority of patients with HA and HPRL and the half of the patients with IH. Cluster #2 included only two hyperandrogenic patients, who were massively obese and in whom ultrasonography may have failed to detect PCOS. Cluster #3 (16 patients) included patients from each diagnostic group, who were gathered together because ultrasonographic and hormonal features were, respectively, present and absent in nearly all of them. With the same analysis, the criteria of PCOS could be graded according to their grouping potential. The presence of an abnormal ovarian stroma by ultrasonography appeared as the most potent criterion. Elevated serum testosterone and androstenedione levels and the polyfollicular pattern of ovaries gave intermediate results, while elevated basal LH level was a much weaker grouping parameter. In conclusion, the automatic classification of patients by cluster analysis using both hormonal and ultrasonographic criteria revealed that the classical diagnostic classification, relying upon hormonal data exclusively, may arbitrarily separate patients having the same disease; and that ultrasonography affords pertinent information that should help provide a better diagnostic definition of PCOS.

Adolescent↗
PubMed1993

Somatostatin receptors, adenylate cyclase activity, and growth hormone (GH) response to octreotide in GH-secreting adenomas.

To determine the cellular mechanism(s) of the variability in GH responsiveness to octreotide in acromegaly, somatostatin (SRIH) receptor status was studied in 37 GH-secreting adenomas. SRIH receptor binding was always present in all GH-secreting adenomas either in membrane preparations (Exp A; n = 17) or by quantitative autoradiography (Exp B; n = 20). In membranes, maximal binding capacities ranged from 83-2331 fmol/mg protein; affinity was in the nanomolar range (Kd, 1.3 +/- 0.2 nmol/L). By quantitative autoradiography, SRIH-14 and octreotide were equally active in displacing [125I]SRIH binding in tumors (Spearman correlation rho = 0.92). IC50 values ranged from 3-22 nmol/L (mean +/- SE, 8.0 +/- 1.3 nmol/L). In Exp A, basal adenylate cyclase (AC) activity was high in 7 tumors (841 +/- 306 pmol/L cAMP x 30 min/mg protein) compared to that in the other 10 (252 +/- 92 pmol/L cAMP x 30 min/mg protein). In these 7 tumors, GH-releasing hormone (0.1 mumol/L) stimulation of AC was lower (53 +/- 11% vs. 297 +/- 48%), whereas SRIH (1 mumol/L) inhibition was higher (52 +/- 5% vs. 34 +/- 5%). Similar results were obtained with Exp B tumors. In both experiments, no correlation was apparent between SRIH-binding capacity and inhibition of AC. In Exp B, a variable decrease in mean plasma GH levels was observed (> or = 80% in 5 patients, between 50-80% in 8 patients, and < or = 50% in 5 patients) after a single sc injection of octreotide (100 micrograms). A modest correlation was found between the GH response to octreotide and SRIH-binding capacity (rho = 0.48) or SRIH inhibition of AC (rho = 0.61). The IC50 values to displace SRIH binding were lower in poorly responsive patients than in highly responsive ones (IC50, 4.6 +/- 1.9 and 13.9 +/- 2.7 nmol/L, respectively). These data indicate that an absence of SRIH receptors cannot account for the weak response to SRIH therapy in 20-30% of acromegalic patients. Alternatively, the weak correlation between either SRIH binding or SRIH inhibition of AC with octreotide inhibition of plasma GH levels might reflect the heterogeneity of SRIH receptor subtypes in GH-secreting adenomas.

Adenoma↗
PubMed1993

[Searching for prolactin microadenoma: scanner or MRI?].

Thirty three hyperprolactinemic women, aged 16-46 years, have been investigated by pituitary CT and MRI scans, searching for a microadenoma. The MRI scan with Gadolinium injection (MRI G+) appeared more efficient than the CT scan to detect a picture highly suggestive of a microprolactinoma (30/33 positive scans vs 21/33, respectively, p = 0.06). However, when the CT scan was performed optimaly (i.e. thin cuts, sequential imaging after iode injection, no artefact), its diagnostic potenty was close to the one of MRI G+, missing only 17.6% of lesions. All these were less than 5 mm in diameter. The indirect signs of microadenoma (focal convexity of the superior surface of pituitary, tilting of pituitary stalk, focal sella floor erosion or destruction) had a minimal value. Their sensitivity was 66.6% and 63.3 for convexity, and 63.3 and 46.6% for tilting of pituitary stalk, by MRI and CT scans, respectively. Therefore, they did not afford any help in our experience. Considering the cost and the limited accessibility of MRI, at least in our country, we advise to use CT scan as the primary morphologic means to detect a microadenoma.

Adolescent↗
PubMed1992

Puberty and polycystic ovarian syndrome: the insulin/insulin-like growth factor I hypothesis.

OBJECTIVES: To provide an up-to-date review of studies that have examined the physiological effects of insulin and insulin-like growth factor I (IGF-I) on ovarian growth, maturation, and steroid synthesis, their physiological role in puberty, and their pathophysiological role in polycystic ovarian syndrome (PCOS). To deduce from these data a hypothesis, explaining the pathogenetic connections between puberty and PCOS. DATA IDENTIFICATION: The most relevant studies related to this topic have been identified through a computerized bibliographic search (MEDLINE) and through manual scanning of what has been published during recent years in the most important journals in the field of reproductive endocrinology. RESULTS: Insulin and IGF-I stimulate ovarian growth and potentiate the actions of gonadotropins on ovarian steroid synthesis. Insulin also augments the bioactive concentrations of IGF-I and androgens through regulation of the synthesis of their respective binding proteins insulin-like growth factor-1 binding protein (IGFBP-1) and sex hormone-binding globulin (SHBG) in the liver. Insulin and IGF-I might also be able to increase the adrenal sensitivity to adrenocorticotropic hormone (ACTH). Insulin resistance with compensating hyperinsulinism is a common feature of PCOS. It is also a normal phenomenon during puberty. Polycystic ovarian syndrome often develops during puberty. Ultrasonographic investigations suggest that it is much more common during adolescence than generally assumed. Actually, there is a striking resemblance between the endocrine characteristics of puberty and some forms of PCOS. Both conditions are characterized by insulin resistance, hyperpulsatile gonadotropin secretion, hyperactive ovarian and adrenal androgen synthesis, and decreased levels of IGFBP-1 and SHBG. CONCLUSION: We propose the progressively increasing insulin levels and IGF-I activity during puberty as inducing factors in the development of PCOS in susceptible subjects.

Female↗
PubMed1992

Insulin resistance and polycystic ovarian syndrome.

Insulin resistance (IR) and polycystic ovarian syndrome (PCOS) appear as linked phenomena, although this is not easy to obviate in common forms of PCOS while it is evident in the rare cases of extreme IR and hyperinsulinism (HI). Experimental data indicate that insulin could interfere with the local insulin-like growth factor systems in ovaries, and presumably in adrenals and in the hypothalamic pituitary system. The female puberty system offers a physiological model to explain the gonadotropic action of insulin. In patients with IR, HI could induce a state of hyperpuberty, leading to the constitution of PCOS during adolescence.

Female↗
PubMed1992

Resistance to somatostatin (SRIH) analog therapy in acromegaly. Re-evaluation of the correlation between the SRIH receptor status of the pituitary tumor and the in vivo inhibition of GH secretion in response to SRIH analog.

The development of a long-acting somatostatin (SRIH) analog (octreotide, Sandoz) has been a major breakthrough in the treatment of acromegaly. However, in 20-30% of the patients, growth hormone (GH) plasma levels remain elevated (> 10 micrograms/l) despite treatment with octreotide. This raised the concept of resistance to SRIH analog therapy in acromegaly. Indeed, in vivo response to SRIH analogs varies greatly among acromegalic patients. According to the reviews in the literature and our own autoradiographic data, no direct correlation can be established between the GH response to octreotide and the number or affinity of the SRIH receptors located on the tumor. In our series a greater density of SRIH receptors is present on tumors from patients very sensitive to the SRIH agonist. A subset of patients resistant to octreotide could result from a very low density of SRIH receptor although this type of GH-secreting tumor constitutes certainly a rare case. A subset of GH-secreting pituitary tumors can be characterized by a mutation on the alpha subunit of the guanine nucleotide-dependent protein coupled to the stimulation of adenylate cyclase (G alpha s). This mutation results in a high basal adenylate cyclase activity and a low GHRH-stimulated activity. However, when the adenomas are separated according to their basal adenylate cyclase activity, SRIH is able to decrease cAMP levels in both types of tumor. In addition, in our series no direct correlation is observed between the SRIH inhibition of adenylate cyclase and the amount of SRIH-binding sites.(ABSTRACT TRUNCATED AT 250 WORDS)

Acromegaly↗
PubMed1992

Effects of the dopamine agonist CV 205-502 in human prolactinomas resistant to bromocriptine.

In 21 patients with prolactinomas resistant to bromocriptine, we studied the effects of CV 205-502 on PRL hypersecretion and tumor mass, as assessed by consecutive computed tomography examinations. Cell culture studies were performed in 9 of such tumors. In 11 patients (group I; 52%) with a mean baseline plasma PRL level of 468 +/- 160 micrograms/L (+/- SE), normal PRL values were achieved after 1-6 months of treatment with 0.1-0.5 mg/day CV 205-502. Tumor size was reduced by 25% or more in 6 of 11 patients. In group II (n = 10), PRL levels (948 +/- 538 micrograms/L at baseline) were reduced by 48% after treatment with 0.1 mg/day CV 205-502. A progressive increase in the daily dose up to 0.5 mg did not further improve the partial reduction of PRL. No reduction in tumor size was observed in this group. The cell culture studies showed that 1) a brief exposure to both drugs provoked PRL suppression lasting 3 days; 2) in group I, CV 205-502 suppressed PRL release more efficiently than bromocriptine, with a maximal inhibition of 72% at 10(-9) mol/L; and 3) in group II, CV 205-502 only achieved a 26% inhibition of PRL release at 10(-8) mol/L, superimposable to that of bromocriptine. These data indicate that in at least half of such adenomas resistant to bromocriptine, CV 205-502, probably due to its higher affinity toward the D2 dopamine receptor, can overcome such resistance.

Adult↗
PubMed1992

[Glycoprotein hormones, glycosylation and biological activity].

Glycoprotein hormones LH, FSH, TSH and hCG are heterodimeric molecules: each contains two subunits, a common alpha and a unique beta subunit. Each subunit bears one or two Asparagine linked carbohydrate moieties which have a biantennary complex-type or hybrid-type structure. Different technical methods as deglycosylation or molecular biology techniques have been used to study the role of carbohydrate residues in hormonal bioactivity. The carbohydrate chains are not directly involved in receptor binding events but their mechanisms of action is not fully understood. Two hypotheses are frequently emphasised: a conformational role or an involvement in the coupling of the receptor-adenylate cyclase system. At the post receptor level carbohydrate chains modulate the bioactivity in two ways: a global regulation following an all-or-none mode and slight one. The removal of the carbohydrate moieties leads to a loss of the in vitro hormonal activity. The results observed are dependent of the deglycosylation techniques and the bioactivity tests used. Hormone's deglycosylation reduces their capacity of production of cAMP and, to a lesser extent, their steroidogenic power. Deglycosylated hormones are antagonists to negative hormones although deglycosylated hCG has some agonist properties in vivo. Microheterogeneity of the glycoprotein hormones is due to slight variations in sialic acid and/or sulfate content. Glycoprotein hormones exist as several isoforms which differ in biological potency. Alkaline isoforms (less sialylated ones) are the most biologically active in vitro but have a short half live in vivo; acid isoforms are less active in vitro but have a longer circulatory half live. The polymorphism of glycoprotein hormones is a highly regulated process.(ABSTRACT TRUNCATED AT 250 WORDS)

Chorionic Gonadotropin↗
PubMed1992

[Insulin resistance and polycystic ovary syndrome].

The causes and consequences of the insulin resistance that accompanies the polycystic ovary Syndrome (PCOS) are still controversial. The hyperandrogenism does not appear any more as a causal factor but on the contrary is likely to be a consequence, via the ovarian effects of hyperinsulinism. These are still not clearly understood in their molecular aspects, but their reality is undoubtful in view of some clinical studies which showed an improvement following by the reduction of hyperinsulinism. Therefore, the aetiopathogenic role of the insulin resistance in PCOS becomes more and more obvious but it cannot be split from the likely implication of the intra-ovarian growth factors, and more especially the IGF 1 which could act synergistically with it. Moreover, the presence of LH seems to be still a pre-requisite to the ovarian action of insulin. The therapeutical incidences of these hypothesis are obvious and should improve in the next future the medical management of PCOS.

Androgens↗
PubMed1992

A long-acting repeatable form of bromocriptine as long-term treatment of prolactin-secreting macroadenomas: a multicenter study.

OBJECTIVE: To assess the efficacy and tolerability of monthly injections of the long-acting repeatable bromocriptine in patients with macroprolactinomas. DESIGN: Open and prospective trial. SETTING: This multicenter trial was carried out in seven university hospitals. PATIENTS: Forty-two patients with prolactin (PRL)-secreting macroadenomas. INTERVENTIONS: Fifty to 200 mg of the drug were administered intragluteally every 28 days for 6 to 24 months. MAIN OUTCOME MEASURES: The efficacy was assessed by repetitive plasma PRL measurements, visual field determinations, and computed tomography scan examinations. RESULTS: After the first 50-mg injection, the mean percentage decrease of PRL levels was 71% from baseline on day 14; between days 1 and 28, PRL levels were suppressed to normal in nine cases, and a clear tumor shrinkage was documented in 21% of the patients. Normalization of PRL secretion was obtained in 62%, and a clear-cut reduction in tumor size in 50% of the patients after 6 months of treatment. CONCLUSIONS: The long-acting repeatable form of bromocriptine was a well tolerated and quickly effective treatment in most of these patients with macroprolactinomas.

Adenoma↗
PubMed1991

Polycystic ovarian disease: contribution of vaginal endosonography and reassessment of ultrasonic diagnosis.

OBJECTIVE: We evaluated the superiority of vaginal ultrasonography (US) on the abdominal US for the diagnosis of polycystic ovarian disease (PCOD). DESIGN: The US pattern of ovaries was prospectively investigated by abdominal US and, whenever possible, by vaginal US. SETTING: Primary care, institutional. PATIENTS: One hundred forty-four women in whom PCOD was suspected on endocrine grounds and 62 other patients presenting with primary hyperprolactinemia (n = 23) or hypothalamic anovulation (n = 39). MAIN OUTCOME MEASURE: Vaginal US allowed a better analysis of the ovarian stroma. RESULTS: The external ovarian features of PCOD were observed by both routes in less than one third of the 144 patients with PCOD. The internal ovarian features of PCOD were much more frequently observed by vaginal US than by abdominal US (polycystic pattern: 66.7% versus 38.1%, P less than 0.05; increased ovarian stroma: 57.1% versus 4.8%, P less than 0.001). In the 62 patients without PCOD, US features of PCOD were observed in less than 10% of them, except for the uterine width/ovarian length ratio less than 1 and the polycystic pattern (abdominal US: 17% and 34%; vaginal US: 11% and 50%, respectively). CONCLUSIONS: An increased ovarian stroma seems to be the most sensitive and specific US sign of PCOD, providing that it can be investigated by vaginal US.

Abdomen↗
PubMed1991

[Short-term effect of delayed-action injectable bromocriptine in macroprolactinoma. French multicenter study].

In this prospective multicenter trial, 61 patients presenting with a macroprolactinoma were studied over a 1 month-period following a single 50 mg intragluteal injection of the long-acting repeatable (L.A.R.) form of bromocriptine. The effects of the drug were evaluated mainly by repetitive plasma prolactin measurements on days 1, 3, 7, 14 and 28 after injection, and by repeated visual-field and computed tomography scanning examinations. Normalization of PRL levels was obtained in 23% of patients during the first month following injection. In 6 patients (9.8%), PRL values remained within normal range on day 28 after injection. In these latter patients, PRL levels were significantly lower than in the patients whose PRL values were not normal on day 28 (312 +/- 111 vs 2454 +/- 484 ng/ml [m +/- SEM]). The mean lowest PRL levels were achieved on day 3. The mean percent maximal decrease in PRL levels ranged between 70 and 72% from days 3 to 14 but constantly remained below 50% in 6 patients. An improvement in visual field was observed by day 7 in 45% of patients presenting initially with visual field defects. In particular, in half of the patients with bilateral quadranopsia or hemianopsia, such visual impairments had disappeared after 1 month of treatment. Computed tomography scanning examinations showed in 11% of the patients a more than 20% reduction in tumor mass by day 7 following injection. On day 28, the percent reduction in tumor size was 20-40% in 28% and above 40% in 10% of the patients. Most adverse effects (digestive symptoms, dizziness, postural hypotension) were observed during the first 24 hours of treatment. Local and systemic tolerability was in general good. In macroprolactinoma patients, a single 50 mg injection of bromocriptine LAR was thus able to achieve in the short-term a clear cut reduction in tumor size in 2/5 patients and normalization of PRL levels in 1/10 of patients. A study of the effects of monthly administration of bromocriptine LAR is currently under progress to assess the long-term efficacy of this drug.

Adult↗